text stringlengths 61 141k | meta dict |
|---|---|
1. Field of the Invention
Embodiments of the invention described herein pertain to the field of viscous, thixotropic impression materials. More particularly, but not by way of limitation, one or more embodiments of the invention enable an apparatus, system and method for mixing and dispensing dental impression materials.
2. Description of the Related Art
During the practice of dentistry or orthodontics, it becomes necessary from time to time to take an impression of a patient's teeth in order to provide treatment or to complete a required procedure, such as filling a cavity or fitting a retainer. Conventionally, creating an oral impression is a two step process, which occurs in a dentist or orthodontist's office. First, an impression or negative mold of the patient's teeth is created. To create the mold, a viscous, thixotropic impression material, typically sodium alginate, is prepared by measuring a powder (e.g., alginate powder), and then mixing the powder with a precise quantity of water in an open container or bowl using a paddle or spatula. The impression material is mixed until smooth and even in consistency, forming a paste, after which it is put into a dental impression tray and placed in the patient's mouth. After a short period of time, the impression compound sets and becomes firm. Upon removal from the patient's mouth, an impression of the patient's dental arrangement is left in the tray.
The next step is to create a cast from the mold. A plaster derivative, such as dental stone, is prepared, again by measuring out and mixing a dry powder with a precise quantity of water to form a paste. The paste is mixed with a spatula in a bowl, and is then scooped into the dental impression mold to cast a mock-up of the patient's dental arrangement (teeth) once the paste dries. From this model, the dentist or orthodontist may plan treatment procedures, or make dental appliances suitable for the specific patient's dental arrangement.
Currently, the measuring and mixing required to prepare the impression materials is a tedious, messy and cumbersome manual process. Quantities of dry powder and water must be carefully measured, the wetted powders must be thoroughly and evenly mixed by hand, and once mixed, scooped and transferred into the impression tray. In a typical alginate impression, 1-2 ounces of water and about 2 ounces of powder must be carefully combined and then spatulated aggressively to reach a creamy consistency. The whole process must be completed quickly and with considerable force. For example, if the process is not completed quickly enough, the compound may prematurely set. If enough force is not used, the mixture may not reach the necessary smooth and creamy consistency.
There are a number of difficulties with this common method of dental impression preparation. One problem is the consistency and uniformity required of the impression compound mixtures. The ratio of water to powder is required to be precise, and this precision is dependent on the complete incorporation of water into the powder. If some of the powder is un-wetted and unmixed due to being in inaccessible places in the mixing cup or poor mixing technique, the ratio of water to powder is effectively too high, and the compound will not perform properly. Areas of unmixed powder may also clump and not flow properly.
The impression compound is also sensitive to the formation and entrapment of bubbles, which bubbles negatively affect the smoothness of the resulting molds and casts. In addition, the impression powder is prone to “slumping”. This causes a disparity between the required amount and the actual dispensed amount, which discrepancy can be as high as 30%.
Another problem is that the impression and dental stone compounds consist of a fine powder before being mixed with water. This powder becomes air-borne during the preparation process, and can be irritating if inhaled. Additionally, the powder can get into instruments and equipment in the dental office, some of which are quite expensive and intolerant to this type of contamination.
A further problem is the sterility and cleanliness of the equipment used to mix the compounds. Every item going into the patient's mouth during dental and orthodontic procedures must be sterilized, usually by use of an autoclave, a type of oven that applies heat, which kills any harmful micro-organisms that may reside on the instruments or appliances being sterilized. The paddles, bowls and other equipment currently used to prepare impression compound are not able to withstand the heat of the autoclave procedure, and are therefore difficult to sterilize.
Yet another problem arises once the impression material or plaster derivative is mixed and must be transferred to the impression tray. It is difficult to efficiently transfer the compound without leaving much of it behind in the mixing cup. Once the impression process is complete, a sticky mess is left behind with many bowls, spatulas and/or spoons to disinfect.
Currently, polyvinyl siloxane is sometimes used as a mold material, rather than sodium alginate, in an attempt to address some of the problems associated with the preparation of dental impression materials. Polyvinyl siloxane is an elastomeric epoxy that results from combining two viscous liquids, rather than mixing dry powder with water. These viscous liquids are sometimes dispensed with a squeeze gun. However, polyvinyl siloxane is between ten and twenty times the cost of sodium alginate, and is therefore often cost prohibitive. In addition, even if polyvinyl siloxane is used as the impression compound, the dental stone for the cast must still be mixed with water from a dry powder in the aforementioned manner.
Thus, mixing and dispensing dental impression materials using conventional systems and methods suffers from a large number of shortcomings. Therefore, there is a need for an apparatus, system and method for mixing and dispensing dental impression materials. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to an apparatus for cell culture, more particularly to an apparatus for high-throughput cell culture with mechanical compression stimulation.
2. Description of the Related Art
Examples of conventional bioreactors used for tissue engineering are spinner flask bioreactors, rotating-wall vessels, hollow-fiber bioreactors, perfusion bioreactors, and so forth. Continuously, simultaneously, and equivalently importing a fresh culture medium into a culture vessel and exporting a waste culture medium out of the culture vessel can be regarded as perfusion culture. Consequently, a volume of a culture medium in the aforementioned culture vessel can be maintained constant. Accordingly, a conventional perfusion cell culture system is able to provide a steady and quantifiable culture condition that is favorable for establishing a quantitative link between an extracellular stimulus and a cellular response.
However, the conventional perfusion cell culture system has a large size and a high production cost, is not configured to be easily operated, and is not appropriate for high throughput applications. The disadvantages of the conventional perfusion cell culture system may limit a range of applications of the same.
Furthermore, in order to investigate a relationship between mechanical compression stimulation and cell physiology, a new miniature device that is suitable for perfusion cell culture, that can overcome the aforementioned disadvantages of the conventional perfusion cell culture system, and that is capable of providing mechanical compression stimulation, is required. For example, the new miniature device can be operated to examine how mechanical compression stimulation may influence differentiation of stem cells or tissue growth regarding tissue engineering. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to railroad tank cars, and in particular to a handbrake arrangement for a railroad tank car.
Most railroad tank cars have handbrake arrangements that allow brakes to be set on both trucks by operation of a handwheel located at an end platform on the tank car. Conventional arrangements, however, require a person to climb onto the end of the tank car to operate the handbrake, and there is a resulting risk of injury.
In a conventional handbrake linkage a chain, or a combination of a chain and tension-carrying rods, extends from a lever normally operated by a pneumatic cylinder-and-piston assembly that is part of an airbrake system to a winch operated by the handwheel located on the end platform at the end of the tank car nearer to the airbrake cylinder-and-piston assembly. The chain conventionally extends through three or more sheave blocks, however, in order to avoid interference with the wheeled truck, as the chain extends to the handbrake winch, with the result that a significant amount of friction opposes take-up of the handbrake-operating chain and thus adds difficulty to the process of setting the handbrake effectively.
In order to reduce or eliminate the risk of injury to personnel and also to facilitate having handbrakes reliably set, it is desired to have a handbrake arrangement that enables brakes to be set on both trucks of a railroad tank car without the necessity for a person to climb up onto the car and with a reduced amount of friction opposing the setting of the handbrake. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to apparatus for illuminating an object and for providing a uniform, thin line of light onto an object for line scan applications. More specifically, the invention relates to light line units of modular design that can be butted end to end to provide very long, seamless lines of light. The invention is more particularly directed to an optical fiber based unit which can conduct light from a remote light source and convert the illumination from that source into a thin, long line of light.
Light line units are employed in a variety of applications where a long, narrow strip of light is needed. Light line units can be used in line-scan applications, e.g., with line-scan type CCD cameras in web-type applications The current preference for a light line unit employs a fluorescent robe and an elongated aperture to produce a line of light. The fluorescent tube light line units have difficulty producing a line of light that is uniform from one end of the line to the other, or a light that remains uniform over time. The fluorescent units have temperature-sensitive output fluctuations, and outputs that vary with age and with other conditions. Also, if two units are to be joined to provide a light line of extra length, there is additional illumination drop-off between modules.
Optical fibers have been used as line illuminators, and one example is described in U.S. Pat. No. 4,952,022 to Genovese. In the Genovese patent, the illuminating device is comprised of a bundle of large-diameter fibers, in which the distal ends or termini are deformed into a rectangular cross section. There, the idea was to produce a linear beam that is uniform along the output of the array. However, the patent does not address how to join two or more units to produce a very long linear beam with no drop-off or discontinuity from one modular unit to another. Another system for transmitting a linear beam of light from a lamp to a workpiece using optical fibers is described in U.S. Pat. No. 3,192,843 to Kapany et al. In the system of that patent, there are alternating layers of illuminating fibers and imaging fibers, and no provision for joining a number of units end-to-end for any reason
In a number of industrial applications, it is necessary to provide a line of illumination up to several meters in length, and with uniformities of better than 10% in a transmission or reflective mode. A typical application can be automated quality inspection of a web type product that travels past, for example a fabric or carpet. The quality of the inspection depends entirely on the uniformity of the light source, that is, on uniformity across the light line. Such high uniformity has been difficult to achieve using standard techniques, such as apertured fluorescent lamps. In addition, inspection of heat-sensitive materials requires remoting the light source from the product, and this has been impossible with conventional linear light sources. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This disclosure relates generally to a computer-based method of rendering an image of a three-dimensional structure from several views of the structure. In particular, the computer-based method for creating a roof model relies upon a statistical method of point pattern matching of an aerial top plan view and one or more aerial perspective views of the roof.
2. Description of the Related Art
The building and insurance industries have historically relied on human beings to evaluate roofs in person, to determine labor and materials needed for repair or replacement. Sending a claims adjuster or a roofing specialist out to each individual property can be time-consuming and costly, especially when many buildings need to be evaluated, for instance, following natural disasters such as hurricanes, floods, hail storms, and the like. If the roof is complex, including multiples of roof features such as hips, gables, dormers, and the like, it may not be feasible for a human being to climb onto the roof to take actual measurements. Consequently, insurance evaluations for such roofs often rely on estimates made by a person standing on the ground, who can only give a rough estimate of the sizes of the roof features.
Recently, imaging and mapping technologies have made possible computer-based calculations of roof dimensions from aerial photographs. A top plan view (“orthogonal”) looking straight down from above, together with one or more different perspective views (“oblique”) looking at an angle from, for example, the north, south, east, or west directions, can be sufficient to generate a three-dimensional (3D) reconstruction depth model of the roof structure. Such a 3D model can include roof features such as dormers, gables, hips, and the like that can add a significant degree of complexity to a roof. Accurate measurements of roof lines and areas can then be made from the 3D model. Such methods pertaining to roofs are described in U.S. Pat. Nos. 8,088,436 and 8,170,840. Furthermore, there are many techniques known in the art (e.g., in the field of computer vision) for generation of 3D models of structures from multiple perspective images. Such 3D architectural images have many applications in the building industry.
In the generation of a 3D roof model, combining information from orthogonal and oblique views of the roof entails an initial step of point matching. First, a set of points is identified on each view to represent the shape of the roof, and then corresponding points from each view are matched. Usually the points are at locations where the roof lines merge. Human beings can easily recognize and associate points from the orthogonal view that match points on the oblique view. For example, it is easy for a human being to identify which points are the highest points on either view of the roof, and which points are the lowest. However, requiring human intervention to perform the step of point matching precludes achieving a fully computer-generated model. When many roof models need to be processed, it is inefficient and cumbersome to interrupt a computerized process to obtain a human-generated data set, and then resume the computerized process.
Unfortunately, existing computerized point matching algorithms for performing such a task (e.g., geometrical contour matching, or the scale invariant feature transform (SIFT) technique of feature matching) tend to be complex and exhaustive. For example, if N=20 points are identified on an orthogonal view of a roof and M=10 points are identified on an oblique view of the roof, if all possible permutations are considered, nearly 200,000 potential point match sets must be evaluated to complete the step of point matching. Thus, a more efficient method of computer-based point matching is desirable. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention deals with parsing text. More specifically, the present invention deals with improvements in left-corner chart parsing.
Parsing refers to the process of analyzing a text string into its component parts and categorizing those parts. This can be part of processing either artificial languages (C++, Java, HTML, XML, etc.) or natural languages (English, French, Japanese, etc.) For example, parsing the English sentence, the man with the umbrella opened the large wooden door, would normally involve recognizing that: opened is the main verb of the sentence, the subject of opened is the noun phrase the man with the umbrella, the object of opened is the noun phrase the large wooden door,with the man with the umbrella and the large wooden door being further analyzed into their component parts. The fact that parsing is nontrivial is illustrated by the fact that the sentence contains the substring the umbrella opened, which in isolation could be a full sentence, but in this case is not even a complete phrase of the larger sentence.
Parsing by computer is sometimes performed by a program that is specific to a particular language, but often a general-purpose parsing algorithm is used with a formal grammar for a specific language to parse strings in that language. That is, rather than having separate programs for parsing English and French, a single program is used to parse both languages, but it is supplied with a grammar of English to parse English text, and a grammar of French to parse French text.
Perhaps the most fundamental type of formal grammar is context-free grammar. A context-free grammar consists of terminal symbols, which are the tokens of the language; a set of nonterminal symbols, which are analyzed into sequences of terminals and other nonterminals; a set of productions, which specify the analyses; and a distinguished “top” nonterminal symbol, which specifies the strings that can stand alone as complete expressions of the language.
The productions of a context-free grammar can be expressed in the form A→X1 . . . Xn where A is a single nonterminal symbol, and X1 . . . Xn is a sequence of n terminals and/or nonterminals. The interpretation of a production A→X1 . . . Xn is that a string can be categorized by the nonterminal A if it consists of a sequence of contiguous substrings that can be categorized by X1 . . . Xn.
The goal of parsing is to find an analysis of a string of text as an instance of the top symbol of the grammar, according to the productions of the grammar. To illustrate, suppose we have the following grammar for a tiny fragment of English: S→NP VP NP→Name Name→john Name→mary VP→V NP V→likes
In this grammar, terminals are all lower case, nonterminals begin with an upper case letter, and S is the distinguished top symbol of the grammar. The productions can be read as saying that a sentence can consist of a noun phrase followed by a verb phrase, a noun phrase can consist of a name, john and mary can be names, a verb phrase can consist of a verb followed by a noun phrase, and likes can be a verb. It should be easy to see that the string john likes mary can be analyzed as a complete sentence of the language defined by this grammar according the following structure: (S: (NP: (Name: john)) (VP: (V: likes) (NP: (Name: mary))))
For parsing natural language, often grammar formalisms are used that augment context-free grammar in some way, such as adding features to the nonterminal symbols of the grammar, and providing a mechanism to propagate and test the values of the features. For example, the nonterminals NP and VP might be given the feature number, which can be tested to make sure that singular subjects go with singular verbs and plural subjects go with plural verbs. Nevertheless, even natural-language parsers that use one of these more complex grammar formalisms are usually based on some extension of one of the well-known algorithms for parsing with context-free grammars.
Grammars for artificial languages, such as programming languages (C++, Java, etc.) or text mark-up languages (HTML, XML, etc.) are usually designed so that they can be parsed deterministically. That is, they are designed so that the grammatical structure of an expression can be built up one token at a time without ever having to guess how things fit together. This means that parsing can be performed very fast and is rarely a significant performance issue in processing these languages.
Natural languages, on the other hand, cannot be parsed deterministically, because it is often necessary to look far ahead before it can be determined how an earlier phrase is to be analyzed. Consider for example the two sentences: Visiting relatives often stay too long. Visiting relatives often requires a long trip.
In the first sentence, visiting relatives refers to relatives who visit, while in the second sentence it refers to the act of paying a visit to relatives. In any reasonable grammar for English, these two instances of visiting relatives would receive different grammatical analyses. The earliest point in the sentences where this can be determined, however, is after the word often. It is hard to imagine a way to parse these sentences, such that the correct analysis could be assigned with certainty to visiting relatives before it is combined with the analysis of the rest of the sentence.
The existence of nondeterminacy in parsing natural languages means that sometimes hundreds, or even thousands, of hypotheses about the analyses of parts of a sentence must be considered before a complete parse of the entire sentence is found. Moreover, many sentences are grammatically ambiguous, having multiple parses that require additional information to chose between. In this case, it is desirable to be able to find all parses of a sentence, so that additional knowledge sources can be used later to make the final selection of the correct parse. The high degree of nondeterminacy and ambiguity in natural languages means that parsing natural language is computationally expensive, and as grammars are made more detailed in order to describe the structure of natural-language expressions more accurately, the complexity of parsing with those grammars increases. Thus in almost every application of natural-language processing, the computation time needed for parsing is a serious issue, and faster parsing algorithms are always desirable to improve performance.
“Chart parsing” or “tabular parsing” refers to a broad class of efficient parsing algorithms that build a collection of data structures representing segments of the input partially or completely analyzed as a phrase of some category in the grammar. These data structures are individually referred to as “edges” and the collection of edges derived in parsing a particular string is referred to as a “chart”. In these algorithms, efficient parsing is achieved by the use of dynamic programming, which simply means that if the same chart edge is derived in more than one way, only one copy is retained for further processing.
The present invention is directed to a set of improvements to a particular family of chart parsing algorithms referred to as “left-corner” chart parsing. Left-corner parsing algorithms are distinguished by the fact that an instance of a given production is hypothesized when an instance of the left-most symbol on the right-hand side of the production has been recognized. This symbol is sometimes called the “left corner” of the production; hence, the name of the approach. For example, if VP→V NP is a production in the grammar, and a terminal symbol of category V has been found in the input, then a left-corner parsing algorithm would consider the possibility that the V in the input should combine with a NP to its right to form a VP. | {
"pile_set_name": "USPTO Backgrounds"
} |
Referring to FIG. 1, FIG. 1 illustrates a prior electrical connector, such as a Taiwan utility model patent publication No. M276350 (Application No. 094205123), which discloses a first shell 11, a second shell 12, and a terminal base 13. The terminal base 13 is provided with a plurality of terminals 14 and is covered in the first shell 11, the first shell 11 is provided with catching portions 111 respectively at two side walls thereof, and the second shell 12 is provided with latching portions 121 respectively at two side walls thereof. The latching portions 121 may be respectively correspondingly engaged with the catching portions 111 so that the second shell 12 may be fixed outside the first shell 11, and the second shell 12 is provided with connecting legs 122 respectively at left and right sides thereof, connecting legs 122 may be disposed to respectively pass through through-holes of a circuit board (not shown), so that the electrical connector may be fixedly soldered on the circuit board.
However, the first shell and the second shell of the electrical connector are assembled by a latching mode, and thus are not firmly fixed therebetween. Therefore, the first shell and the second shell are relatively shifted due to shock yielded from an external force (for example, if conveyed by a conveyer belt) during soldering the electrical connector to the circuit board. Accordingly, a through-hole type design must be adopted for the connecting legs of the second shell. If a Surface Mount Technology (SMT)-TYPE is alternatively used, it is easy to cause that the SMT-TYPE connecting legs of the second shell and the SMT-TYPE soldering portions of the terminals are not coplanar, and a problem of missing solder for the terminals of the electrical connector is possible, with the potential result that signal transmission will be poor. Secondly, also because the first shell and the second shell are assembled by the latching mode and not firmly fixed therebetween, there is a gap between the first shell and the second shell, so that most stress during inserting or withdrawing a mating counterpart connector is still born by the first shell when the mating counterpart connector is inserted into or withdrawn from the electrical connector, and in turn will be born by the soldering portions of the terminals, thereby easily making the electrical connector to be released, that is to say, there is a phenomenon that the terminals will be released. On the other hand, because the circuit board belongs to a multilayer-sheet structure design, the number of the through-holes would influence on a wiring layout inside the circuit board. As a result, the connecting legs of the second shell disposed to respectively pass through the through-holes of the circuit board may make a problem on the wring layout design for the circuit board serious, and may result in increased cost. Consequentially, certain individuals would appreciate an improved connector. | {
"pile_set_name": "USPTO Backgrounds"
} |
The popularity of commercial wireless communications services (e.g., wireless telephony, wireless network access, and wireless email) has substantially increased during recent years. In many cases, users, such as consumers, mobile workers, emergency response personnel, and/or the like, now utilize these services for both personal and business communications. Likewise, users are also increasingly relying on these services. For example, some households forgo wired telephone service in favor of wireless telephone service, some government agencies rely on these services for both routine and emergency communications, and businesses rely on these services to communicate with customers and mobile workers. Correspondingly, the cost (both financial and nonfinancial) of outages is also increasing.
Typical commercial wireless communications service (CMRS) providers rely on remote facilities to facilitate the provision of services. For instance, CMRS providers rely on base stations (e.g., cell sites, radio repeaters, wireless to backhaul interfaces, etc.) to facilitate some communications services. If a base station experiences a loss of commercially-provided electrical power, users near the base station may experience a service outage. Power outages are an example of a common cause for base station failures. For example, natural disasters, rolling brownouts, accidents, and/or the like may result in power outages. While most base stations include some form of backup power (e.g., generators and/or batteries), these forms of backup power may not provide sufficient power during lengthy power outages and may require servicing, monitoring, and on-site maintenance. During lengthy power outages, use of commercial wireless communications services may increase due to users' needs and/or desires. Further, pending regulations may require commercial wireless communications service providers to provide base stations with at least seven days of backup power. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention generally relates to manufacturing, remanufacturing or repairing replaceable imaging components, and more particularly to apparatus and techniques for providing a drive gear for a drum or roller, such as an organic photo conductor (OPC) drum, for example, of a replaceable imaging cartridge adapted for holding marking material, such as toner.
In the imaging industry, there is a growing market for the remanufacture and refurbishing of various types of replaceable imaging cartridges such as toner cartridges, drum cartridges, inkjet cartridges, and the like. These imaging cartridges are used in imaging devices such as laser printers, xerographic copiers, inkjet printers, facsimile machines and the like, for example. Imaging cartridges, once spent, are unusable for their originally intended purpose. Without a refurbishing process these cartridges would simply be discarded, even though the cartridge itself may still have potential life. As a result, techniques have been developed specifically to address this issue. These processes may entail, for example, the disassembly of the various structures of the cartridge, replacing toner or ink, cleaning, adjusting or replacing any worn components and reassembling the imaging cartridge.
Laser printer toner cartridges are typically composed of two portions. One of these sections is the waste bin assembly which houses the OPC drum. The OPC may include a drive gear which engages with a printer drive member. During the remanufacturing of a laser printer toner cartridge, the OPC drum may need to be replaced due to the wear or damage of the OPC drum. The replacement OPC drum may include a replacement drive gear, or gear, attached to one end of the replacement OPC drum. The present invention provides for an improved replacement drive gear. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a frequency synthesizer for use in a transmitter/receiver. More specifically, the present invention relates to a frequency synthesizer for use in a transmitter/receiver adapted to be capable of providing an oscillation frequency signal of various desired frequencies.
2. Description of the Prior Art
A digital frequency synthesizer has been proposed and in practical use. Such a frequency synthesizer is much more advantageous in that it can provide a much more stabilized oscillation frequency. A typical frequency synthesizer employs a phase locked loop, which is often simply referred to as "PLL."
A frequency synthesizer employing a phase locked loop usually comprises a voltage controlled oscillator the oscillation frequency of which is controllable as a function of an output voltage, as low pass filtered, obtainable from a phase detector, which is adapted to compare the phase or the frequency of the output from a reference oscillator and the phase or the frequency of an output from a programmable frequency divider adapted to frequency divide the output frequency from the said voltage controlled oscillator at the frequency division rate which is adapted to be variable as a function of a control signal. Automatic scanning of the oscillation frequency of the output from the said voltage controlled oscillator is effected by varying the said control signal and thus the frequency division rate of the programmable frequency divider.
Such a frequency synthesizer has been utilized by way of a frequency signal generator in a citizens band transceiver, for example. However, since in a citizens band transceiver the frequency of the received signal in the receiving mode is in any one frequency band within the frequency range of 29.965 MHz through 27.255 MHz depending on the channel of the received signal, the oscillation frequency of the frequency signal generator should also be changed within the frequency range of 37.66 MHz through 37.92 MHz depending on the receiving channel in order to obtain a constant intermediate frequency of 10.695 MHz. On the other hand, in the transmitting mode, the oscillation frequency of the frequency signal generator should be changed within the frequency range of 26.965 MHz through 27.255 MHz depending on the channel in which a modulated carrier wave is to be transmitted. A typical approach for changing the frequency variable range depending on the transmitting and receiving modes in such a frequency signal generator employing a frequency synthesizer comprises two reference oscillators, which are typically crystal oscillators. One of them is a reference oscillator to be included basically in a frequency synthesizer for providing a reference signal of the frequency of 26.965 MHz to be phase detected and the other oscillator is a reference oscillator to be used only on the occasion of reception for providing a reference frequency of 10.695 MHz to be mixed with the output from a voltage controlled oscillator to be used by way of a local oscillator.
As described previously, a typical prior art frequency synthesizer to be used in a transceiver comprises at least two crystal oscillators. Since provision of one such crystal oscillator entails an increase of cost of approximately ten percent of the whole apparatus, reduction of cost in this connection is of great interest. If any scheme can be implemented which is capable of skillfully selecting the transmitting and receiving modes with a less number of crystal oscillators, then it would be much advantageous from the stand point of cost, even if a configuration of the circuit concerned becomes complicated, insofar as the circuit is implemented by an integrated circuit. | {
"pile_set_name": "USPTO Backgrounds"
} |
Cancer remains one of the leading causes of death among humans worldwide. Current treatment methods often involve chemotherapy, surgery and/or radiation therapy. These mechanisms, while effective in short term treatment, are often accompanied by harsh side effects and offer little guarantee of preventing future relapses. In light of these problems, other long-term strategies for treating cancer have been researched.
One such strategy involves the use of exogenous mechanisms to stimulate a patient's immune system to target the aberrant cancer cells. Rosenberg, S. A. Nature. 411 380-384 (2001); Dudley, et al. Nat Rev Cancer. 3 666-675 (2003); Boon, et al. Annu Rev Immunol. 24 175-208 (2006). More specifically, tumor cells are understood in the art to display unique proteins on their cell surface that may act as antigens. Such antigens are most often comprised of epitopes or small peptide sequences within the antigen that, when recognized by the host's immune system, generate an immunological response. Such an immunological response occurs when the antigenic protein is engulfed and degraded within an antigen presenting cell through intracellular proteolytic breakdown. Peptide fragments, i.e. epitopes, are then associated with immunity stimulating molecules of the Major Histocompatibility Complex (MHC), often in the endoplasmic reticulum of the cell and transported to the cell surface for extracellular presentation and immunological stimulation. With respect to cancer cells, peptide antigens are often associated with class I MHC molecules and presented on the cell surface of the cancer cell.
The MHC class I molecule is a tetramer comprised of an alpha and a beta chain. The alpha chain has three polymorphic domains, α1, α2, α3 wherein the degraded antigen binds within clefts formed therebetween. Because one MHC molecule can bind numerous antigens, each molecule is named according to its locus within the Human Leukocyte Antigen (HLA) region of the genome. More specifically, HLA-A, HLA-B, and HLA-C each refer to different loci wherein superfamilies of Class I MHC molecules are encoded, and HLA-DP, HLA-DQ, and HLA-DR each refer to different loci where Class II MHC molecules are encoded. Once the appropriate MHC molecule is bound to the antigen and the complex is transported to the cell surface, the cell is then in a condition for recognition by, for example, a lymphocyte.
T lymphocytes (T cells), among many functions, recognize antigens or immunodominant epitopes that are associated with alleles of the human leukocyte antigens (HLA). There are at least two distinct types of T lymphocytes: CD4+ helper T lymphocytes (TH cells) and CD8+ cytotoxic T lymphocytes (CTLs). TH cells are involved in both humoral and cell-mediated forms of immune responses and typically, though not exclusively, recognize antigens in association with class II MHC molecules. CTLs, however, recognize and destroy cells which display foreign antigens on their surfaces wherein the antigens are typically associated with class I MHC molecules. The CTL's recognition of such foreign antigens occurs through a T cell receptor (TCR) located on the surface of the CTL.
A TCR is a immunoglobin protein that may be comprised of at least an alpha chain with a variable region and a constant region, a beta chain with a variable region and a constant region, and a transmembrane region. The variable region of the alpha chain may by comprised of at least three complementarity determining regions (cdr1, cdr2, and cdr3, respectively) and the variable region of the beta chain may be comprised of at least four complementarity determining regions (cdr1, cdr2, cdr3, and cdr4, respectively). While all three cdr regions of the alpha chain and all four cdr regions of the beta chain function to facilitate recognition of an antigen/MHC complex, the cdr3 is the most variable and plays a large role in determining which epitopes and antigen/MHC complex(s) the TCR will recognize. Recognition of an antigen/MHC complex by the TCR triggers a cascade of protein and cytokine interactions leading to, among other interactions, the activation, maturation and proliferation of the precursor CTLs and resulting in CTL clones capable of destroying the cells exhibiting the antigens recognized as foreign.
Paraneoplastic neurologic disorders (PND) are autoimmune disorders caused by an onconeural antigen eliciting such a CTL mediated response. More specifically, cerebellar degeneration-related 2 protein (cdr2 protein) is one such onconeural protein normally expressed within immunoprivileged sites of the cerebellar Purkinje neurons in the brain, some brainstem neurons, and spermatogonia. Corradi, et al. J Neurosci. 17 1406-1415 (1997). However, research into paraneoplastic cereballar degeneration (PCD), a PND disorder wherein the patient's immune system destroys Purkinje neurons in the cerebellar cortex of the brain, revealed that the cdr2 protein is not limited to these cell types and may also be found within some gynecological tumor cells. (FIG. 1 in Corradi, et al. J Neurosci. 17 1406-1415 (1997)). Current research further suggests that the autoimmune effects of PCD are actually caused by cdr2-specific CTLs stimulated by the cdr2-expressing gynecologic carcinomas. Albert, et al. Nat. Med. 4 1321-1324 (1998). In other words, cdr2-specific CTLs within the PCD patient, while competent to elicit an immunological response to the cdr2 expressing tumor cells, secondarily recognize and elicit an autoimmune response to the cdr2 expressing Purkinje cells. Accordingly, the epitopes of the cdr2 proteins are, in fact, onconeural antigens in that they signal the presence of a carcinoma, but also elicit an autoimmune response to neural cells.
Another such onconeural antigen is an antigen of the Hu protein family. The Hu protein family, also normally expressed exclusively in neurons, has been linked as a intracellular antigen associated with small cell lung cancers (SCLC). Darnell, et al. J Neurosci. 11 1224-1230, Darnell, et al. Proc Natl Acad Sci USA 93 4529-4536. It is believed that HuD expression by tumor cells exposes the antigen to the immune system, generating an HuD-specific and CTL driven immune response. This results in appropriate and partially effective tumor immunity against the SCLC. Darnell et al. N Engl J Med. 349 1543-1554, Darnell et al. Semin Oncol 33 170-298. However, many Hu patients typically first present to clinicians with neurological symptoms triggered when this CTL driven tumor immune response, by unknown means, becomes competent to attack the nervous system, i.e. HuD expressing neurons.
There are, however, large populations of individuals with similar onconeural antigen expressing tumors who do not develop a PND. Darnell et al. Cancer Res. 60 2136-2139 (2000), Dalmau et al. Ann Neurol 27 544-552. Such populations suggest that antigen directed immunotherapy may be possible without the risk of developing PND, but only if the appropriate epitopes can be established. In fact, ˜20% of SLCL patients develop immune responses to the Hu antigen that correlate with improved clinical outcome, in the absence any signs of neurologic PND symptoms Graus, F. et al. J. Clin. Oncol. 15, 2866-2872 (1997); Dalmau, J., Furneaux, H. M., Gralla, R. J., Kris, M. G. & Posner, J. B. Ann. Neurol. 27, 544-552 (1990). In particular, strategies that might target a peripheral tumor, but that are not able to either get across the blood-brain barrier or are otherwise incompetent to attack neurons, may target tumor cells without inducing autoimmune disease. However, exactly which onconeural antigens are optimally recognized by a CTL, and which corresponding TCRs are present on those T cells were previously unknown.
Based on the foregoing, there is a need in the art for compositions and methods providing therapeutic avenues of treatment for subjects suffering from onconeural antigen expressing tumors and/or a PND. The present invention addresses and meets this need by providing a series of HLA allele-specific, immunodominant peptides as disclosed that elicit an immune response to the carcinoma with little to no autoimmue side-effect. Moreover, this invention addresses these needs by identifying TCRs able to recognize these HLA-peptide complexes present on tumor cells, and demonstrates that they are sufficient to induce killing in an otherwise naïve CTL. | {
"pile_set_name": "USPTO Backgrounds"
} |
The basic process of plasma enhanced chemical vapor deposition (PECVD) is described in THIN FILM PROCESSES, J. L. Vossen, W. Kern, editors, Academic Press, 1978, Part IV, Chapter IV-1 Plasma Deposition of Inorganic Compounds, Chapter IV-2 Glow Discharge Polymerization, herein incorporated by reference. Briefly, a glow discharge plasma is generated on an electrode that may be smooth or have pointed projections. Traditionally, a gas inlet introduces high vapor pressure monomeric gases into the plasma region wherein radicals are formed so that upon subsequent collisions with the substrate, some of the radicals in the monomers chemically bond or cross link (cure) on the substrate. The high vapor pressure monomeric gases include gases of CH4, SiH4, C2H6, C2H2, or gases generated from high vapor pressure liquid, for example styrene (10 torr at 87.4° F. (30.8° C.)), hexane (100 torr at 60.4° F. (15.8° C.)), tetramethyldisiloxane (10 torr at 82.9° F. (28.3° C.)), 1,3,-dichlorotetramethyldisiloxane (75 torr at 44.6° F. (7.0° C.)), and combinations thereof that maybe evaporated with mild controlled heating. Because these high vapor pressure monomeric gases do not readily cryocondense at ambient or elevated temperatures, deposition rates are low (a few tenths of micrometer/min maximum) relying on radicals chemically bonding to the surface of interest instead of cryocondensation. Remission due to etching of the surface of interest by the plasma competes with the reactive deposition. Lower vapor pressure species have not been used in PECVD because heating the higher molecular weight monomers to a temperature sufficient to vaporize them generally causes a reaction prior to vaporization, or metering of the gas becomes difficult to control, either of which is inoperative.
The basic process of flash evaporation is described in U.S. Pat. No. 4,954,371 herein incorporated by reference. This basic process may also be referred to as polymer multi-layer (PML) flash evaporation. Briefly, a radiation polymerizable and/or cross linkable material is supplied at a temperature below a decomposition temperature and polymerization temperature of the material. The material is atomized to droplets having a droplet size ranging from about 1 to about 50 microns. An ultrasonic atomizer is generally used. The droplets are then flash vaporized, under vacuum, by contact with a heated surface above the boiling point of the material, but below the temperature which would cause pyrolysis. The vapor is cryocondensed on a substrate then radiation polymerized or cross linked as a very thin polymer layer.
The material may include a base monomer or mixture thereof, cross linking agents and/or initiating agents. A disadvantage of the flash evaporation is that it requires two sequential steps, cryocondensation followed by curing or cross linking, that are both spatially and temporally separate.
According to the state of the art of making plasma polymerized films, PECVD and flash evaporation or glow discharge plasma deposition and flash evaporation have not been used in combination. However, plasma treatment of a substrate using glow discharge plasma generator with inorganic compounds has been used in combination with flash evaporation under a low pressure (vacuum) atmosphere as reported in J. D. Affinito, M. E. Gross, C. A. Coronado, and P. M. Martin, “Vacuum Deposition Of Polymer Electrolytes On Flexible Substrates,” Proceedings of the Ninth International Conference on Vacuum Web Coating, November 1995, ed. R. Bakish, Bakish Press 1995, pg. 20-36, and as shown in FIG. 1a. In that system, the plasma generator 100 is used to etch the surface 102 of a moving substrate 104 in preparation to receive the monomeric gaseous output from the flash evaporation 106 that cryocondenses on the etched surface 102 and is then passed by a first curing station (not shown), for example electron beam or ultra-violet radiation, to initiate cross linking and curing. The plasma generator 100 has a housing 108 with a gas inlet 110. The gas may be oxygen, nitrogen, water or an inert gas, for example argon, or combinations thereof. Internally, an electrode 112 that is smooth or having one or more pointed projections 114 produces a glow discharge and makes a plasma with the gas which etches the surface 102. The flash evaporator 106 has a housing 116, with a monomer inlet 118 and an atomizing nozzle 120, for example an ultrasonic atomizer. Flow through the nozzle 120 is atomized into particles or droplets 122 which strike the heated surface 124 whereupon the particles or droplets 122 are flash evaporated into a gas that flows past a series of baffles 126 (optional) to an outlet 128 and cryocondenses on the surface 102. Although other gas flow distribution arrangements have been used, it has been found that the baffles 126 provide adequate gas flow distribution or uniformity while permitting ease of scaling up to large surfaces 102. A curing station (not shown) is located downstream of the flash evaporator 106.
In all of these prior art methods, the starting monomer is a (meth)acrylate monomer (FIG. 1b). When R1 is hydrogen (H), the compound is an acrylate and when R1 is a methyl group (CH3), the compound is a methacrylate.
It is known that the monomer composition may be varied to selectively obtain a desired refractive index. Acrylated or methacrylated hydrocarbon chain compositions provide indices of refraction tightly grouped about 1.5. Bisphenyl A diacrylate has an index of refraction of 1.53. The degree of conjugation (the number of carbon to carbon double or triple bonds or aromatic rings) generally increases index of refraction. For example, polyvinylcarbizone has an index of refraction of 2.1 or higher. However, multi-ring system compounds that are solids are not useful as a monomer in these systems. The addition of bromine may increase index of refraction as high as 1.7. The addition of fluorine may reduce index of refraction to as low as 1.3. However, bromine adds a brown color and tends to oxidize over time, and fluorinated monomers have high vapor pressures, poor adhesion and high cost.
Therefore, there is a need for a method for making plasma polymerized polymer layers at a fast rate but that is also self curing, and with selective index of refraction. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates generally to apparatus for removing material and more particularly, by not by way of limitation, to apparatus for removing asbestos from walls without contaminating the ambient environment.
2. Description of the Prior Art
It is often necessary to remove various materials from their natural or fabricated locations, such as rock formations or interior building walls. For example, it is currently necessary to remove deposits of asbestos found in building materials which have been used in such places as schools. This necessity for asbestos removal has arisen from the discovery that asbestos is, or may be, a carcinogen. Thus, there is the need for an apparatus which can remove the desired materials by cutting, scraping, or otherwise removing, them from the desired locations.
To prevent the removed material from dispersing throughout the ambient environment and thereby possibly causing contamination, such as could occur with particles of asbestos, it is necessary to perform removal without allowing the removed particles arising from the cutting or other removing process to filter into the ambient environment. Thus, there is the need for the apparatus to contain the removed particles, such as by coagulating the particles into a bonded mass, and to withdraw them from the removal area.
Prior to using such an apparatus to remove material from a structure, it is necessary to determine if that particular structure contains any of the material desired to be removed. For example, some materials have the appearance of containing asbestos, but they are in fact non-asbestos materials. Therefore, there is the need for means for sampling the subject structure. This sampling means should provide for the obtaining of uniform bulk samples of the material of the subject structure and should provide for the safe containment of the sample if the material were dangerous.
That there is the general need for an apparatus for cutting or scraping a surface and removing the material therefrom is supported by U.S. Pat. No. 3,843,198 in the name of Reynolds. This patent discloses a rock sampling tool which cuts the rock from a surface and which uses an air stream to reduce dispersal of the resultant dust into the surrounding area.
Although the Reynolds patent discloses such a device, it will be noted that individual particles of dust resulting from the rock cutting operation may escape into the ambient environment without being drawn into the air stream of Reynolds' device because of the tendency of certain substances to scatter or disperse upon being cut, scraped, or otherwise loosened. This is a critical shortcoming when the material to be removed is asbestos, for example, because the escape of even a few particles of asbestos can create a serious health hazard. Furthermore, the Reynolds reference fails to disclose a sampling container for extracting and safely holding a portion of the substance so that it can be analyzed. Therefore, I believe that the prior art fails to provide an apparatus for removing a material, such as asbestos, from a structure, such as the interior walls of a school, in which the material is located without allowing particles of the removed material to escape into the ambient environment. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Technical Field
This invention relates to trailer hitch assemblies and, more particularly, to a trailer hitch assembly for towing various types of boats between remote locations such that the boats can be loaded and unloaded from a water ramp without requiring a rear end of a towing vehicle to dip down into the water.
2. Prior Art
As any boat enthusiast knows, there are severe limitations to conventional boat trailers which prevent the enthusiast from launching or retrieving his boat in shallow water, or at low tide, or in the event his boat has a deep keel, such as, for example, in the case of sailboats which are provided with relatively deep fixed keels. While these adverse conditions are not always present when the boater wishes to enjoy the pleasures afforded by boating or sailing, they nevertheless may limit his full use of his or her boat.
There have been attempts in the prior art to minimize the loss of full use of boats for the operator by arranging boat trailer tongues with extension devices which permit the operator to elongate the tongue so that the vehicle towing the trailer need not drive his vehicle too close to, or into the water's edge, and yet be able to move the trailer further out into the water, thereby avoiding inadvertent scraping of the bottom of the launch site by his boat keel.
A disadvantage with some of the conventional tongue and extension mechanisms is that these extensions are integrated into, and are a part of, the tongue itself, and thereby become too expensive for the average boater. These arrangements require that those boaters who presently own and operate conventional boat trailers must discard their boat trailer and purchase a new one in the event that they need the same only occasionally. It would thus be advantageous to have an extending mechanism that may be attached to a conventional trailer. One example shows a boat trailer extension tongue wherein an extension having a rack gear is arranged to telescope within the tubular frame of the boat trailer in order to lengthen or shorten the total length of the tongue. In this arrangement, the extension and associated structure is integrated with a boat trailer, thereby requiring the operator to purchase the boat trailer with this accessory whether he needs it or not.
Another disadvantage of the prior art examples for extending the tongue of a boat trailer is the fact that they must be manually operated. This can be very time and energy consuming, and thus may discourage a boater from using their water craft as often as they would like.
Accordingly, a need remains for an extendable trailer hitch assembly in order to overcome the above-noted shortcomings. The present invention satisfies such a need by providing a trailer hitch assembly that is easy to use, durable in design, remotely extendable, and increases time-savings and safety. Such an extendable trailer hitch assembly has an extendable length so that the rear of a towing vehicle advantageously remains clear of the water, thus preventing rust damage to the vehicle. The boater further prevents the slipping and spinning of his wheels on the ramp upon exiting the ramp, since the vehicle's tires do not become wet. This greatly improves the safety of launching and loading a water craft, while also extending the life of the vehicle's tires. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The embodiments described herein are directed to non-volatile memory devices, and more particularly to the fabrication of embedded non-volatile memory device and CMOS logic devices using the same fabrication process.
2. Background of the Invention
Many non-volatile semiconductor memories are based on the well known MOS-type structure. In other words, they comprise a gate structure separated from a substrate by a dielectric layer. Diffusion regions are implanted in the substrate under the corners of the gate structure. When the appropriate voltages are applied to the diffusion regions and the control gate, a channel can be created in the upper layers of the substrate between the diffusion regions and under the gate structure. Carriers, e.g., electrons, can travel the channel between the diffusion regions.
If a sufficient field component is present in the direction of the gate structure, the carriers, e.g., electrons, can be attracted to the gate structure. If the electrons have enough energy to overcome the barrier height of the dielectric layer, then these carriers can be injected through the dielectric layer.
An example non-volatile memory device is the Flash memory device. Flash memory has been widely adopted for a number of non-volatile memory applications. Flash devices were originally introduces as a replacement for Ultra Violet (UV) erasable Electrically Programmable Read Only Memory (EPROM). Today, however, Flash has not just taken over large parts of the One Time Programmable (OTP) and EPROM markets, but it has also become a significant competitor for Electrically Erasable Read Only Memory (EEPROM) and even for some Random Access Memory (RAM) applications.
Due to Flash's origin as a EPROM replacement, most Flash designs are based on cells derived from EPROM technology or EEPROM technology. Accordingly, many flash cell concepts have drawbacks, especially with respect to embedded applications. These drawbacks include low programming speed, high power consumption, high programming voltages, over erase problems, soft write problems, and high process complexity.
This later issue can be especially problematic for embedded applications where memory cells are often closely integrated with CMOS logic and other circuitry, because not only are Flash processes complex, they are also typically incompatible with conventional CMOS processes. Accordingly, including Flash in an embedded application can significantly increase fabrication time and cost.
Several new memory types have been introduced with the aim of overcoming the disadvantages of Flash memory listed above, especially with respect to embedded applications; however, most of these new designs are still incompatible with conventional CMOS processes. Some newer designs have been introduced that are somewhat compatible with conventional CMOS techniques; however, even these designs still require several additional masks. Accordingly, even these newer designs have increased complexity, time and costs compared with conventional CMOS processes. | {
"pile_set_name": "USPTO Backgrounds"
} |
Absorbent articles are typically used in contact with skin. Some absorbent articles such as disposable diapers, feminine pads, panty liners, incontinence pads and the like are held in contact with skin to absorb body liquids or exudates, while other absorbent materials such as paper towels, hand towels, and wipers may be held in the hands to absorb liquid on the skin or other surfaces. In virtually every case, it is desired that the absorbent article or material keep liquids off the skin to provide a clean, dry feel and to reduce skin health problems that arise from excess hydration or from contact with harmful biological or chemical materials in the liquid being absorbed.
While paper towels and wipers are often composed of a homogenous material, such as an entirely cellulosic web, absorbent articles intended to absorb body fluids typically have at least three layers of different materials. Next to the user""s skin is a topsheet layer, sometimes herein referred to as a liner, body-side liner or cover sheet. Beneath the topsheet is the absorbent core that is designed to retain liquid, and beneath the absorbent core is a fluid-impervious backsheet that prevents leakage and maintains the integrity of the product. The topsheet should feel soft and should have high liquid permeability to allow body fluid such as urine, menses, or runny bowel movement to be absorbed and transported away from the skin to reach the central absorbent core. Ideally, the topsheet provides a xe2x80x9cdry touchxe2x80x9d or xe2x80x9cdry feelxe2x80x9d by preventing liquid from flowing back to the skin. It is also desirable that the topsheets have high wet resiliency to maintain their bulk and shape when wet.
Traditional hydrophilic cover materials or topsheets in contact with the skin can serve effectively to transport body fluids into the absorbent core, but they cause a wet feel against the skin of the user and may adversely affect skin health. Further, they may wick liquid in the plane of the layer, allowing liquid to approach the edges of the absorbent article and possibly leak or seep out.
To achieve the goal of softness and a dry feel in topsheets of absorbent articles, many manufacturers have turned to nonwoven fabrics made of hydrophobic fibers for the body-contacting topsheet. While the use of hydrophobic nonwoven fabrics may have resulted in improved dry feel, the hydrophobic material hinders wicking into the absorbent core, offers little absorbent capacity and reduces liquid permeability. Further, the poor absorbency of most hydrophobic materials causes any liquid retained therein to be easily squeezed out by body motion of the wearer.
Others have sought to improve the poor wicking and absorbent properties of hydrophobic materials by applying a finish comprising surfactants on the surface of the hydrophobic fibers. This approach may offer some benefits when the article is first wetted, but the surfactants tend to be washed away, resulting in poorer performance upon further wetting.
In the case of absorbent pads for feminine care, two distinct approaches involving hydrophobic topsheets or covers are common. One approach is to use a soft, clothlike nonwoven hydrophobic material, which increases comfort but has the drawback of poor intake of menses. Another approach is to use an apertured plastic film of hydrophobic polymer or other materials. The hydrophobic cover material repels many body fluids, while the apertures allow wicking away from the cover into the absorbent material beneath.
In theory, the hydrophobic apertured material should allow the user""s skin to remain relatively dry while allowing wicking in the z-direction (normal to the plane of the cover) into the underlying absorbent core. In practice, hydrophobic apertured films present a number of problems. Apertured films have the drawback of being disliked by some users for their plastic feel and for their poor absorbency. Their hydrophobic nature resists transport through the material, possibly delaying wicking into the absorbent core. Likewise, pockets or pools of liquid may form between the film and the user""s skin. In the absence of hydraulic pressure or physical compression, menses in particular may pool on the hydrophobic surface and not penetrate into the apertures, especially if there is a significant interfacial gap between the cover and the underlying absorbent material.
Therefore there is a need for an improved topsheet material which provides the clean feel said to be characteristic of hydrophobic topsheet materials, while also providing for rapid z-direction (depthwise) transport of liquid through the topsheet into the underlying absorbent core, a characteristic more typical of hydrophilic materials. Preferably, these absorbent topsheets also have wet resiliency and absorbency properties which persist upon multiple insults of urine or other liquids.
The present invention pertains to composite, resilient materials that offer the once-thought mutually exclusive benefits of high absorbency and a clean, dry feel when used as skin-contacting layers that absorb body fluids or other liquids.
In copending U.S. application, Ser. No. 08/614,420, xe2x80x9cWet Resilient Webs and Disposable Articles Made Therewith,xe2x80x9d by F. -J. Chen et al., herein incorporated by reference, a novel wet-laid tissue web is taught having unusually high bulk, wet resiliency, in-plane permeability, and absorbency. The unusual properties of this material are achieved through a combination of high yield fibers, wet strength additives, and noncompressive drying of a molded, three-dimensional structure. The three-dimensional structure of this material does not collapse readily when wetted and thus reduces the contact area with the skin when wet, contributing to a relatively dry feel. It has been found that the inherently hydrophilic material of this previous invention and related materials can be made substantially more useful in personal care articles by the selective addition of hydrophobic material which can impart increased dry feel and, in some embodiments, improved softness. With hydrophobic material deposited on the uppermost, body-contacting regions of the three-dimensional hydrophilic web, the highest body-contacting regions are made substantially hydrophobic to increase the sensation of a clean, dry feel, while a plurality of hydrophilic regions in said web remain accessible to body fluids, allowing liquids to be wicked away from the body and into an absorbent medium. Thus, dry feel and high absorbency are achieved in a single unitary layer or in a single composite structure which may be a laminate of hydrophobic and hydrophilic materials. The hydrophobic material is bonded or integrally attached to the basesheet. Improved disposable absorbent articles comprising such materials include feminine pads and panty liners, incontinence products such as diapers and liners, bed pads, disposable diapers, pull-ups or disposable training pants, disposable menstrual pants, poultry pads, disposable sweat bands or pads, breast pads, odor absorbing pads for shoes, towels, moisturized wipes, wipers, medical pads, bandages and sterile pads for wounds, disposable garments, liners for helmets or other protective or athletic gear, pads for use in waxing automobiles and other surfaces, and so forth. A simple example of an absorbent article containing a topsheet, absorbent core and a backsheet is illustrated in U.S. Pat. No. 3,809,089 issued May 7, 1974 to Hedstrom et al., which is hereby incorporated by reference.
In general, it has been discovered that the addition of hydrophobic agents. or materials on relatively elevated portions of one surface of a three-dimensional, wet resilient fibrous web, said web predominantly comprising intrinsically hydrophilic fibers, can enhance the suitability of such webs for use in absorbent articles by reducing the amount of fluid that can remain in contact with the skin or flow back to the skin during use as an absorbent article, thus resulting in an improved dry feel. Certain hydrophobic materials such as short, fine synthetic fibers can provide a pleasant soft, fuzzy, and dry feel, while others such as hydrophobic resins, gels, emulsions, waxes, or liquids can increase the apparent smoothness or lubricity of the surface and improve the tactile properties.
Suitable basesheets can be prepared from aqueous slurries of papermaking fibers with known papermaking techniques. The fibers may be derived from wood or other sources of cellulose and preferably containing a portion of high yield or other wet resilient pulp fibers and an effective amount of wet strength agents. The basesheet can be textured by through-drying on a three-dimensional fabric or other means known in the art and preferably non-compressively dried to give a three-dimensional structure. The inherent stiffness of wet resilient pulp fibers may be reduced, if desired, by incorporation of a suitable plasticizer such as glycerol or by mechanical treatment such as microstraining, dry creping, or calendering.
Through-drying fabrics well suited for formation of three-dimensional webs are disclosed in U.S. Pat. No. 5,429,686, issued to Chiu et al., xe2x80x9cApparatus for Making Soft Tissue Products,xe2x80x9d issued Jul. 4, 1995, herein incorporated by reference. Other methods such as wet molding, forming on three-dimensional forming fabrics, drying on nonwoven substrates, rush transfer onto embossing fabrics, embossing, stamping, and so forth may be used to create useful three-dimensional structures. The basesheet may be formed as a unitary multilayer structure in which various plies are well bonded and intimately connected to each other. Unitary multilayer basesheets may be formed using layered or stratified headboxes in which two or more furnishes are provided into separate chambers of a headbox, or they may be formed using separate headboxes by couching the wet webs together prior to drying in order to allow extensive hydrogen bonding to develop between the plies during drying, or they may be formed during air-laying by varying the composition of the fibers and additives imparted to web. Multilayer sheets allow better control of physical properties by tailoring the material composition of each layer. For example, a unitary multilayer basesheet useful for the present invention would have an upper layer, corresponding to the upper surface of the basesheet, and at least one remaining layer below said upper layer and integrally attached thereto, preferably through hydrogen bonds formed between cellulosic fibers during drying, wherein said upper layer differs from at least one remaining layer of the basesheet in terms of material composition. The difference in material composition may be due to differences in fiber species (for example, percentage of hardwood versus softwood); fiber length; fiber yield; fiber treatment with processes which change fiber morphology or chemistry such as mechanical refining, fiber fractionation, dispersing to impart curl, steam explosion, enzymatic treatment, chemical crosslinking, ozonation, bleaching, lumen loading with fillers or other chemical agents, supercritical fluid treatment, including supercritical fluid extraction of agents in the fiber or supercritical fluid deposition of solutes on and into the cell wall, and the like. The difference in material composition between the upper layer and at least one other layer in the basesheet also may be due to differences in added chemicals, including the type, nature, or dosage of added chemicals. The chemicals added differentially to at least one layer of the web may include debonding agents, anti-bacterial agents, wet strength resins, starches, proteins, superabsorbent particles, fiber plasticizers such as glycols, colorants, opacifiers, surfactants, zinc oxide, baking soda, silicone compounds, zeolites, activated carbon, and the like. In a preferred embodiment, the basesheet structure has a wet resilient, noncompressively dried lower layer, preferably composed of softwood fibers, preferably including at least 10% of high yield fiber such as spruce BCTMP, and a soft upper layer containing a portion of finer fibers such as chemically pulped hardwoods. The multilayer basesheet structure is unitary, meaning that the two layers are intimately connected or bonded together. For example, a two-layer unitary basesheet could be formed with a layered headbox or by couching together two wet sheets prior to drying to form intimate contact and hydrogen bonding between the two layers.
The portion of the surface area treated with hydrophobic materials should be great enough to provide an effective improvement in comfort, which will in part depend on the specific product . Accordingly, the fraction of the basesheet surface covered by hydrophobic material can be about 5% or greater, more specifically about 10% or greater, more specifically about 20% or greater, more specifically about 30% or greater, and still more specifically from about 40% to about 75%. The portion of the surface area of the basesheet that remains essentially hydrophilic can be about 10% or greater, more specifically about 20% or greater, more specifically about 30% or greater, more specifically about 40% or greater, more specifically from about 20% to about 90%, and still more specifically from about 50% to about 90%. For effective fluid removal, the lateral width of the depressed hydrophilic regions should be about 0.1 mm or greater, more specifically about 0.5 mm or greater, and still more specifically about 1 mm or greater. The spacing between depressed hydrophilic regions can be about 0.4 mm or greater, more specifically about 0.8 mm or greater, and still more specifically about 1.5 mm or greater. The minimum width of the elevated regions can be about 0.5 mm or greater, more specifically about 1 mm or greater, and still more specifically from about 1 to about 3 mm.
In one preferred embodiment, the hydrophobic matter comprises a substantially contiguous network of hydrophobic fibers having a plurality of macroscopic openings such that a portion of the depressed regions of the basesheet are aligned with openings in the overlaying network of hydrophobic fibers to allow body exudates to pass through the macroscopic openings into the basesheet. A macroscopic opening is defined as an opening that is large relative to the intrinsic pore size of the material. In a typical spunbond or bonded carded web, for example, a macroscopic opening would appear to the eye to be a deliberately introduced hole or void in the web rather than a characteristic pore between adjacent fibers, and specifically could have a characteristic width of about 0.2 mm or greater, about 0.5 mm or greater, about 1 mm or greater, about 2 mm or greater, about 4 mm or greater, about 6 mm or greater, or from about 1 mm to about 5 mm. The characteristic width is defined as 4 times the area of the aperture divided by the perimeter.
The nonwoven web may be made from synthetic fibers, as is known in the art, and may be a spunbond web, a meltblown web, a bonded carded web, or other fibrous nonwoven structures known in the art. For example, a polyolefin nonwoven web such as a low basis weight spunbond material could be provided with apertures through pin aperturing; perf embossing and mechanical stretching of the web; die punching or stamping to provide apertures or holes in the web; hydroentangling to impart apertures by rearrangement of the fibers due to the interaction of water jets with the fibrous web as it resides on a patterned, textured or three-dimensional substrate that imparts a pattern to the web; water knives that cut out desired apertures or holes in the web; laser cutters that cut out portions of the web; patterned forming techniques, such as air laying of synthetic fibers on a patterned substrate to impart macroscopic openings; needle punching with sets of barbed needles to engage and displace fibers; and other methods known in the art. Preferably, the openings are provided in a regular pattern over at least a portion of the topsheet of the absorbent article.
Preferably, the openings in the network of hydrophobic fibers are spaced and registered with respect to the structure of the basesheet such that a predetermined fraction of the openings are largely superposed over depressed regions of the basesheet. An opening is said to be largely superposed over a depressed region if at least half of the area of the macroscopic opening resides over a depressed region of the basesheet. The predetermined fraction of the openings that are largely superposed over depressed regions can be about 0.25 of greater, 0.4 or greater, 0.5 or greater, 0.7 or greater, 0.8 or greater, or from about 0.4 to about 0.85. The contiguous network of hydrophobic matter is laminated to or otherwise physically joined with the underlying basesheet. Preferably, the network of hydrophobic fibers is attached to the basesheet by means of adhesives and related agents, including hot melts, latexes, glues, starch, waxes, and the like, which adhere or join the upper regions of the basesheet with adjacent portions of the overlaying network of hydrophobic fibers. Preferably, adhesives are applied only to the most elevated portions of the basesheet to effect the bonding between the hydrophilic basesheet and the network of hydrophobic fibers with macroscopic openings therein, leaving the depressed regions substantially free of adhesives. Adhesive application can be through meltblown application of hot melt glues and thermoplastic materials, spray or swirl nozzles of melted or dissolved adhesives, printing of adhesive material onto one or both surfaces before joining, and the like. If adhesives are applied directly to the basesheet by means of spray, mist, aerosol, or droplets in any form, prior to contact of the basesheet with the hydrophobic matter, then it is desirable to use a template or patterned shield to prevent application of adhesive to the depressed regions of the basesheet and to ensure that adhesives are preferentially applied to the elevated portions of the basesheet.
For improved comfort, the network of hydrophobic fibers use in the above-mentioned embodiment preferably is one that is perceived as soft and conformable when next to the skin.
For optimum efficiency in the embodiment comprising a nonwoven web, the apertures or openings in the web should be arrayed in a pattern corresponding to the array of depressed regions in the tissue basesheet, or should correspond to a subset of the depressed regions of the basesheet. Applicant have found a useful means for providing apertures in a nonwoven web in a pattern which corresponds geometrically to the depressed regions of a molded, three-dimensional basesheet wherein the basesheet was molded on a foraminous textured substrate such as a three-dimensional through-drying fabric. The method involves hydroentrangling, which is a well known principle involving the use of high pressure water jets to modify a fibrous surface. Basic principles of hydroentangling are disclosed by Evans in U.S. Pat. No. 3,485,706 issued in 1969, and in U.S. Pat. No. 3,494,821 issued in 1970, both of which are herein incorporated by. reference. Hydroentangling, as is known in the art, can be used to impart apertures to a nonwoven web. In one well known technique, the nonwoven web is carried on a textured, permeable carrier fabric. The action of water jets on the nonwoven web as it resides on the textured fabric causes fibers to be moved away from the elevated portions of the carrier fabric on which the nonwoven web reside, resulting in apertures where the carrier fabric was elevated. If a nonwoven web is placed on the same kind of throughdrying fabric that was used to mold a three-dimensional through-dried sheet, preferably an uncreped or only lightly creped sheet in order to preserve texture in the basesheet, then the high places on the carrier TAD fabric will become apertured regions in the nonwoven basesheet. The high portions of the TAD fabric will correspond to the depressed regions on the fabric side of the through-dried sheet. Alternatively, if the nonwoven web is hydroentangled against the backside of a three-dimensional TAD fabric, the elevated regions of the TAD fabric""s backside will generally correspond to the depressed in the air side of the sheet that is through dried on the TAD fabric. In either case, a nonwoven web can be created having apertures that align with the real physical structure of the TAD fabric, namely, with the depressed regions of a through-dried sheet. When the apertured nonwoven material is then attached to the through-dried basesheet, the apertures can be aligned with the depressed regions of the basesheet using techniques known in the art, such as photoelectric eyes or high speed CCD cameras which can view the position of apertures in the nonwoven web relative to the position of the through-dried fabric as the two are brought together, whereupon the position of one material can be adjusted both in the cross-direction and the machine direction (e.g., by controlling the speed of one layer or by machine direction motion of an unwind roll of one material) for proper placement of the two layers together.
In embodiments comprising contiguous nonwoven webs with spaced apart openings for fluid access to the hydrophilic basesheet, Applicants have found excellent fluid intake and absorbency results when the absorbent web is superposed on a separate layer of densified fluff pulp or an air laid cellulosic web, preferably an air laid web stabilized with thermosetting materials or crosslinking chemistry such as Kymene wet strength resin. With a densified cellulosic web beneath the basesheet and hydrophobic matter of the present invention, an insult of fluid that enters the hydrophilic basesheet can be pulled out of the hydrophilic basesheet by capillary suction provided that the local pore size of the underlying absorbent layer is small enough. Experiments with dyed water and also with an aqueous egg white mixture have shown that the combination of a hydrophobicly treated cellulosic basesheet resting on a densified airlaid web can result in greatly improved intake, with fluid being largely directed into the air laid material and not spreading significantly laterally in the basesheet.
It has also been discovered that highly calendered versions of such webs are suitable as hand towels. The hydrophobic, originally uppermost regions are made relatively flat, offering significant hydrophilic areas initially in contact with the wet skin for rapid intake of fluid, but also having the ability to expand after wetting to provide improved dry feel as the wet, hydrophilic areas retract from the skin relative to the more hydrophobic, elevated regions. Webs so treated can achieve the once mutually exclusive goals of having high density for economical dispensing and low density once wetted for high absorbency, while also having a dry feel in use.
Hence, in one aspect, the invention resides in an absorbent web having a dry feel when wet, comprising: (a) an inherently hydrophilic basesheet comprising papermaking fibers and having an upper surface and a lower surface, said upper surface having elevated and depressed regions; and (b) hydrophobic matter deposited preferentially on the elevated regions of the upper surface of said basesheet.
In another aspect, the invention resides in an absorbent dual-zoned web providing a dry feel in use, said web having an upper surface comprising a plurality of hydrophobically treated regions surrounded by inherently hydrophilic cellulosic regions, wherein upon wetting said web expands such that the hydrophobically treated regions are preferentially elevated relative to said hydrophilic regions.
In another aspect, the invention resides in an absorbent web having a Rewet value of about 1 g or less, comprising: (a) an inherently hydrophilic basesheet comprising papermaking fibers and having an upper surface and a lower surface, said upper surface having elevated and depressed regions with an Overall Surface Depth of 0.2 mm or greater in the uncalendered and uncreped state, said basesheet further having a Wet Compressed Bulk of at least 6 cc/g; and (b) hydrophobic matter deposited preferentially on the elevated regions of the upper surface of said basesheet.
In another aspect, the invention resides in an absorbent web having a dry feel when wet, comprising: (a) an inherently hydrophilic basesheet comprising papermaking fibers and having an upper surface and a lower surface, said upper surface having elevated and depressed regions with an Overall Surface Depth of about 0.2 mm or greater; and (b) a substantially contiguous network of hydrophobic fibers having a plurality of macroscopic openings attached to the upper surface of said basesheet such that a portion of the depressed regions of the basesheet are aligned with openings in the overlaying network of hydrophobic fibers to allow body exudates to pass through the macroscopic openings into the basesheet.
In another aspect, the invention resides in an absorbent web having a dry feel when wet, comprising: (a) an inherently hydrophilic basesheet comprising papermaking fibers and having an upper surface and a lower surface, said upper surface having elevated and depressed regions, said basesheet preferably having a wet:dry tensile ratio of at least 0.1; and (b) a contiguous network of hydrophobic matter deposited preferentially on the elevated regions of the upper surface of said basesheet.
In another aspect, the invention resides in an absorbent article comprising a liquid impermeable backsheet, a cellulosic absorbent core in superposed relation with said backsheet, and a liquid permeable absorbent web, said absorbent web comprising an inherently hydrophilic basesheet comprising papermaking fibers and having a wet:dry tensile ratio of at least 0.1, said basesheet having an upper surface and a lower surface, said upper surface having elevated and depressed regions and hydrophobic matter deposited preferentially on the elevated regions, wherein the basesheet is superposed on the absorbent core with the lower surface of the basesheet facing the absorbent core.
In another aspect, the invention resides in an absorbent article comprising a liquid impermeable backsheet, a cellulosic absorbent core in superposed relation with said backsheet, and a liquid permeable absorbent web, said absorbent web comprising an inherently hydrophilic basesheet comprising papermaking fibers, said basesheet having an upper surface and a lower surface, said upper surface having elevated and depressed regions, further comprising an apertured contiguous web of hydrophobic nonwoven material attached to the upper surface of the basesheet such that a portion of said apertures overlay the depressed regions of the basesheet, wherein the basesheet is superposed on the absorbent core with the lower surface of the basesheet facing the absorbent core.
In another aspect, the invention resides in calendered, low density structures of previously three-dimensional resilient webs having hydrophobic matter on the once uppermost regions of one or both sides of the web. Without limitation, such articles may serve as suitable hand towels by providing high initial uptake of fluid by the plurality of hydrophilic regions in the plane of the flat paper during initial wicking, followed by an enhanced dry feel as the dry-feeling treated areas rise out of the plane of the sheet during wetting. The hydrophobic matter in such articles may also be used to increase the apparent softness or lubricity of the article and be applied in contiguous or discontiguous forms.
In another aspect, the invention resides in a method for producing an intake material for an absorbent article, comprising the steps of (a) forming an embryonic paper web from an aqueous slurry of papermaking fibers; (b) through-drying the embryonic paper web on a three-dimensional through-drying fabric having a pattern of elevated and depressed regions; (c) completing the drying of the web; (d) aperturing a nonwoven web by means of hydroentangling, wherein the nonwoven web overlays a carrier fabric having substantially the same pattern of elevated and depressed regions as the through-drying fabric of step (b); and (e) joining the apertured nonwoven web with the through-dried paper web such that the apertures of the nonwoven web are substantially aligned with the depressed regions of the through-dried paper web.
In stating that hydrophobic matter is preferentially deposited on elevated portions of the basesheet, the term xe2x80x9cpreferentiallyxe2x80x9d implies that more hydrophobic matter is deposited on the elevated regions rather than in the depressed regions, in terms of a mass per unit area basis, such that the depressed regions have a significantly lower amount of hydrophobic matter present than the elevated regions. It is preferred that the percentage of the hydrophobic material deposited on the elevated regions be at least about 60 percent, more specifically at least about 70 percent, and still more specifically at least about 80 percent of the total amount deposited. The hydrophobic matter can comprise fine fibers, powders, resins, gels, and other materials, preferably applied with an average superficial basis weight of less than 10 gsm, more specifically from about 1 to about 10 gsm. When used as the skin-contacting layer of absorbent articles, said absorbent web serves as an absorbent improvement over nonabsorbent, plastic apertured films or other inherently hydrophobic materials. The elevated regions of said basesheet preferably comprise between about 5 and about 300 protrusions per square inch having a height relative to the plane of the basesheet, as measured in the uncalendered state, of about 0.1 mm or greater, preferably about 0.2 mm or greater, more preferably about 0.3 mm or greater, and most preferably from about 0.25 to about 0.6 mm.
In describing the webs of this invention and their fluid-handling characteristics, a number of terms and tests are used which are described below.
As used herein, xe2x80x9chigh yield pulp fibersxe2x80x9d are those papermaking fibers of pulps produced by pulping processes providing a yield of about 65 percent or greater, more specifically about 75 percent or greater, and still more specifically from about 75 to about 95 percent. Yield is the resulting amount of processed fiber expressed as a percentage of the initial wood mass. High yield pulps include bleached chemithermomechanical pulp (BCTMP), chemithermomechanical pulp (CTMP) pressure/pressure thermomechanical pulp (PTMP), thermomechanical pulp (TMP), thermomechanical chemical pulp (TMCP), high yield sulfite pulps, and high yield Kraft pulps, all of which contain fibers having high levels of lignin. The preferred high yield pulp fibers can also be characterized by being comprised of comparatively whole, relatively undamaged fibers, having a freeness of 250 Canadian Standard Freeness (CSF) or greater, more specifically 350 CSF or greater, and still more specifically 400 CSF or greater, and low fines content (less than 25 percent, more specifically less than 20 percent, still more specifically less that 15 percent, and still more specifically less than 10 percent by the Britt jar test). In addition to common papermaking fibers listed above, high yield pulp fibers also include other natural fibers such as milkweed seed floss fibers, abaca, hemp, kenaf, bagasse, cotton and the like.
As used herein, xe2x80x9cwet resilient pulp fibersxe2x80x9d are papermaking fibers selected from the group comprising high-yield fibers, chemically stiffened fibers and cross-linked fibers. Examples of chemically stiffened fibers or cross-linked fibers include mercerized fibers, HBA fibers produced by Weyerhaeuser Corp., and those such as described in U.S. Pat. No. 3,224,926, xe2x80x9cMethod of Forming Cross-linked Cellulosic Fibers and Product Thereof,xe2x80x9d issued in 1965 to L. J. Bemardin, and U.S. Pat. No. 3,455,778, xe2x80x9cCreped Tissue Formed From Stiff Cross-linked Fibers and Refined Papermaking Fibers,xe2x80x9d issued in 1969 to L. J. Bemardin. Though any blend of wet resilient pulp fibers can be used, high-yield pulp fibers are the wet resilient fiber of choice for many embodiments of the present invention for their low cost and good fluid handling performance when used according to the principles described below.
The amount of high-yield or wet resilient pulp fibers in the basesheet can be at least about 10 dry weight percent or greater, more specifically about 15 dry weight percent or greater, more specifically about 30 dry weight percent or greater, still more specifically about 50 dry weight percent or greater, and still more specifically from about 20 to 100 percent. For layered basesheets, these same amounts can be applied to one or more of the individual layers. Because wet resilient pulp fibers are generally less soft than other papermaking fibers, in some applications it is advantageous to incorporate them into the middle of the final product, such as placing them in the center layer of a three-layered basesheet or, in the case of a two-ply product, placing them in the inwardly-facing layers of each of the two plies.
xe2x80x9cWater retention valuexe2x80x9d (WRV) is a measure that can be used to characterize some fibers useful for purposes of this invention. WRV is measured by dispersing 0.5 grams of fibers in deionized water, soaking at least 8 hours, then centrifuging the fibers in a 1.9 inch diameter tube with a 100 mesh screen at the bottom of the tube at 1000 G for 20 minutes. The samples are weighed, then dried at 105xc2x0 C. for two hours and then weighed again. WRV is (wet weightxe2x80x94dry weight)/dry weight. High yield pulp fibers can have a WRV of about 0.7 or greater and characteristically have a WRV of about 1 or greater and preferably from about 1 to about 2. Low-yield, cross-linked fibers typically have a Water Retention Value of less than about 1, specifically less than about 0.7 and more specifically still less than about 0.6.
xe2x80x9cRewetxe2x80x9d is a measure of the amount of liquid water which can be wicked out of a moistened web into an adjacent dry filter paper and is intended to estimate the tendency of a moistened web to wet the skin. The Rewet test is performed by cutting a sample of a tissue web to a rectangle of dimensions 4 inxc3x976 in. The test is performed in a Tappi conditioned room (50% RH, 73xc2x0 F.). The initial air dry weight of the conditioned sample is recorded, then deionized water is sprayed onto both sides of the tissue sample to uniformly wet it, bringing the total wet mass of the tissue to a value of 4 times the previously recorded initial air dry weight of the sample, thus bringing the xe2x80x9capparent moisture ratioxe2x80x9d of the sample to a value of 3.0 grams (xc2x10.15 g) of added water per gram of conditioned air dry fiber. The process of repeatedly spraying and weighing the sample until the proper mass has been reached should take no more than 2 minutes. Once the sample is wetted, a single dry Whatman #3 filter, whose mass has been measured and recorded, is placed on the center of the wet tissue sample and a load is immediately placed on the filter disk. The load is a cylindrical disk of aluminum having a diameter of 4.5 inches and a thickness of 1 inch for a mass of 723 g. The aluminum disk should be centered about the filter disk. The filter paper on the wet sample remains under load for 20 seconds, at which time the load and the filter paper are immediately removed. The filter paper is then weighed, and the additional mass relative to the initial air dry mass is reported in grams as the Rewet value.
xe2x80x9cNormalized Rewetxe2x80x9d is the Rewet value of a sample divided by the conditioned dry mass of the sample.
xe2x80x9cAbsorbency at 0.075 psixe2x80x9d is a measure of basesheet absorbent capacity under a load of 0.075 psi. The test requires two metal plates cut to a length of 6 inches and a width of 4 inches. A lower plate is 0.125-inches thick and the upper plate is xc2xe-inch thick aluminum having a mass of 813 g, which imparts a load of 0.075 psi when placed flat on a tissue sample. The center of the upper plate has a cylindrical hole 0.25-inches in diameter. To perform the test, 4-inxc3x976-in samples of dry tissue are cut, with the 6-in length being aligned with the machine direction. Multiple tissue plies are stacked to achieve a tissue stack weight as close to 2.8 grams as possible. The tissue stack is placed between the two horizontal plates, which lie flat in a larger tray. A titrating burette with 50 ml of deionized water is aligned directly above the hole in the upper plate. The burette is opened and water is allowed to slowly enter the hole in the upper plate such that the hole is filled with a column of water that is maintained as high as possible without rising above or spilling onto the upper surface of the plate. This is done until the sample is apparently saturated. Apparent saturation is the point at which water begins to leave any edge of the sample. The mass of water that has been removed from the burette is taken as the value forxe2x80x9cHorizontal Absorbency at 0.075 psi.xe2x80x9d At that point, the tray containing the plates is tilted at a 450 angle for 30 seconds to allow some of the liquid in the sample to drain. The mass of any liquid that drains out is subtracted from the previous xe2x80x9cHorizontal Absorbency at 0.075 psixe2x80x9d value to yield xe2x80x9cTilted Absorbency at 0.075 psi.xe2x80x9d For the basesheet, the horizontal absorbency at 0.075 psi can be about 5 g or greater, or alternatively 7 g or greater, 9 g or greater, 11 g or greater, or from about 6 g to about 10 g. The tilted absorbency at 0.075 psi may be about 4 g or greater, about 6 g or greater, about 8 g or greater, about 10 g or greater, or from about 6 to about 10 g. The tilted absorbency of the cover may be about 5 to 40% less than that off the basesheet alone, while the horizontal absorbency may be greater or lower than that off the basesheet.
xe2x80x9cFabric sidexe2x80x9d of a through-air dried paper web is the side of the web that was in contact with the through-air dryer fabric (TAD fabric) during through-drying. Typically the fabric side of a through-dried sheet offers the most pleasant tactile properties for contact with skin.
xe2x80x9cAir sidexe2x80x9d of a through-air dried paper web is the side of the web that was not in contact with the through-air dryer fabric (TAD fabric) during through-drying. Typically the air side of a through-dried sheet feels somewhat more gritty than the fabric side of the same sheet.
xe2x80x9cDensityxe2x80x9d can be determined by measuring the caliper of a single sheet using a TMI tester (Testing Machines, Inc., Amityville, N.Y.) with a load of 0.289 psi, e.g., using a TMI Model 49-70 with an enlarged platen. Density is calculated by dividing the caliper by the basis weight of the sheet. The basesheets useful for the purposes of this invention can have low, substantially uniform densities (high bulks), which is preferred for wet laid structures, or may have a distribution of zones of varying density, which is preferred in airlaid basesheets. Substantial density uniformity is attained, for example, by throughdrying to final dryness without differentially compressing the web. In general, the density of the basesheets of this invention can be about 0.3 gram per cubic centimeter (g/cc) or less, more specifically about 0.15 g/cc or less, still more specifically about 0.1 g/cc or less and can be from about 0.05 to 0.3 g/cc or from about 0.07 to 0.2 g/cc. It is desirable that the basesheet structure, once formed, be dried without substantially reducing the number of wet-resilient interfiber bonds. Throughdrying, which is a common method for drying tissues and towels, is a preferred method of preserving the structure. Basesheets made by wet laying followed by throughdrying typically have a density of about 0.1 gram per cubic centimeter, whereas airlaid basesheets normally used for diaper fluff typically have densities of about 0.05 gram per cubic centimeter. All of such basesheets are within the scope of this invention.
As used herein, xe2x80x9cdry bulkxe2x80x9d is measured with a thickness gauge having a circular platen 3 inches in diameter such that a pressure of 0.05 psi is applied to the sample, which should be conditioned at 50% relative humidity and at 73xc2x0 F. for 24 hours prior to measurement. The basesheet as well as the uncalendered web can have a dry bulk of 3 cc/g or greater, preferably 6 cc/g or greater, more preferably 9 cc/g or greater, more preferably still 11 cc/g or greater, and most preferably between 8 cc/g and 28 cc/g.
xe2x80x9cWet strength agentsxe2x80x9d are materials used to immobilize the bonds between the fibers in the wet state. Typically the means by which fibers are held together in paper and tissue products involve hydrogen bonds and sometimes combinations of hydrogen bonds and covalent and/or ionic bonds. In the present invention, it is desirable to provide a material that will allow bonding of fibers in such a way as to immobilize the fiber to fiber bond points and make them resistant to disruption in the wet state. In this instance the wet state usually will mean when the product is largely saturated with water or other aqueous solutions, but could also mean significant saturation with body fluids such as urine, blood, mucus, menses, runny bowel movement, lymph and other body exudates.
There are a number of materials commonly used in the paper industry to impart wet strength to paper and board that are applicable to this invention. These materials are known in the art as xe2x80x9cwet strength agentsxe2x80x9d and are commercially available from a wide variety of sources. Any material that when added to a paper web or sheet results in providing the sheet with a wet geometric tensile strength:dry geometric tensile strength ratio in excess of 0.1 will, for purposes of this invention, be termed a wet strength agent. Typically these materials are termed either as permanent wet strength agents or as xe2x80x9ctemporaryxe2x80x9d wet strength agents. For the purposes of differentiating permanent from temporary wet strength, permanent will be defined as those resins which, when incorporated into paper or tissue products, will provide a product that retains more than 50% of its original wet strength after exposure to water for a period of at least five minutes. Temporary wet strength agents are those which show less than 50% of their original wet strength after being saturated with water for five minutes. Both classes of material find application in the present invention. The amount of wet strength agent added to the pulp fibers can be at least about 0.1 dry weight percent, more specifically about 0.2 dry weight percent or greater, and still more specifically from about 0.1 to about 3 dry weight percent based on the dry weight of the fibers.
Permanent wet strength agents will provide a more or less long-term wet resilience to the structure. In contrast, the temporary wet strength agents would provide structures that had low density and high resilience, but would not provide a structure that had long-term resistance to exposure to water or body fluids. The mechanism by which the wet strength is generated has little influence on the products of this invention as long as the essential property of generating water-resistant bonding at the fiber/fiber bond points is obtained.
Suitable permanent wet strength agents are typically water soluble, cationic oligomeric or polymeric resins that are capable of either crosslinking with themselves (homocrosslinking) or with the cellulose or other constituent of the wood fiber. The most widely-used materials for this purpose are the class of polymer known as polyamide-polyamine-epichlorohydrin (PAE) type resins. These materials have been described in patents issued to Keim (U.S. Pat No. 3,700,623 and 3,772,076) and are sold by Hercules, Inc., Wilmington, Del. as KYMENE 557H. Related materials are marketed by Henkel Chemical Co., Charlotte, N.C. and Georgia-Pacific Resins, Inc., Atlanta, Ga.
Polyamide-epichlorohydrin resins are also useful as bonding resins in this invention. Materials developed by Monsanto and marketed under the SANTO RES label are base-activated polyamide-epichlorohydrin resins that can be used in the present invention. These materials are described in patents issued to Petrovich (U.S. Pat. No. 3,885,158; U.S. Pat. No. 3,899,388; U.S. Pat. No. 4,129,528 and U.S. Pat. No. 4,147,586) and van Eenam (U.S. Pat. No. 4,222,921). Although they are not as commonly used in consumer products, polyethylenimine resins are also suitable for immobilizing the bond points in the products of this invention. Another class of permanent-type wet strength agents are exemplified by the aminoplast resins obtained by reaction of formaldehyde with melamine or urea.
Suitable temporary wet strength resins include, but are not limited to, those resins that have been developed by American Cyanamid and are marketed under the name PAREZ 631 NC (now available from Cytec Industries, West Paterson, N.J. This and similar resins are described in U.S. Pat. Nos. 3,556,932 to Coscia et al. and 3,556,933 to Williams et al. Other temporary wet strength agents that should find application in this invention include modified starches such as those available from National Starch and marketed as CO-BOND 1000. It is believed that these and related starches are disclosed in U.S. Pat. No. 4,675,394 to Solarek et al. Derivatized dialdehyde starches, such as described in Japanese Kokai Tokkyo Koho JP 03,185,197, may also provide temporary wet strength. It is also expected that other temporary wet strength materials such as those described in U.S. Pat. No. 4,981,557; U.S. Pat. No. 5,008,344 and U.S. Pat. No. 5,085,736 to Bjorkquist would be of use in this invention. With respect to the classes and the types of wet strength resins listed, it should be understood that this listing is simply to provide examples and that this is neither meant to exclude other types of wet strength resins, nor is it meant to limit the scope of this invention.
Although wet strength agents as described above find particular advantage for use in connection with this invention, other types of bonding agents can also be used to provide the necessary wet resiliency. They can be applied at the wet end of the basesheet manufacturing process or applied by spraying or printing, etc. after the basesheet is formed or after it is dried.
xe2x80x9cNoncompressive dryingxe2x80x9d refers to drying methods for drying cellulosic webs that do not involve compressive nips or other steps causing significant densification or compression of a portion of the web during the drying process. Such methods include through-air drying; air jet impingement drying; non-contacting drying such as air flotation drying, as taught by E. V. Bowden, E. V., Appita J., 44(1): 41 (1991); through-flow or impingement of superheated steam; microwave drying and other radiofrequency or dielectric drying methods; water extraction by supercritical fluids; water extraction by nonaqueous, low surface tension fluids; infrared drying; drying by contact with a film of molten metal; and other methods. It is believed that the three-dimensional basesheets of the present invention could be dried with any of the above mentioned noncompressive drying means without causing significant web densification or a significant loss of their three-dimensional structure and their wet resiliency properties. Standard dry creping technology is viewed as a compressive drying method since the web must be mechanically pressed onto part of the drying surface, causing significant densification of the regions pressed onto the heated Yankee cylinder. Technology to noncompressively dewater and dry tissue webs with an air press and optionally with a Yankee dryer operated without creping is disclosed in the following commonly owned copending applications: U.S. patent application Ser. No. unknown, xe2x80x9cMethod of Producing Low Density Resilient Websxe2x80x9d by F. G. Druecke et al., Attorney Docket No. 13,504, filed Oct. 31, 1997; U.S. patent application Ser. No. unknown, xe2x80x9cLow Density Resilient Webs and Methods of Making Such Webxe2x80x9d by S. Chen et al., Attorney Docket No. 13,381, filed Oct. 31, 1997; U.S patent application Ser. No. 08/647,508 filed May 14, 1996 by M. A. Hermans et al. titled xe2x80x9cMethod and Apparatus for Making Soft Tissue;xe2x80x9d and U.S Patent Application Serial No. unknown filed Oct. 31, 1997 titled xe2x80x9cAir Press for Dewatering a Wet Webxe2x80x9d by F. Hada et al., all of which are herein incorporated by reference. Also of potential value for the tissue making operations useful in the present invention is the paper machine disclosed in U.S. Pat. No. 5,230,776 issued Jul. 27, 1993 to I. A. Andersson et al.; and the capillary dewatering techniques disclosed in U.S. Pat. Nos. 5,598,643 issued Feb. 4, 1997 and U.S. Pat. No. 4,556,450 issued Dec. 3, 1985, both to S. C. Chuang et al., all of which are incorporated herein by reference. The dewatering concepts disclosed by J. D. Lindsay in xe2x80x9cDisplacement Dewatering to Maintain Bulk,xe2x80x9d Paperija Puu, 74(3): 232-242 (1992) are also of potential value.
As used herein, the xe2x80x9cwet:dry ratioxe2x80x9d is the ratio of the geometric mean wet tensile strength divided by the geometric mean dry tensile strength. Geometric mean tensile strength (GMT) is the square root of the product of the machine direction tensile strength and the cross-machine direction tensile strength of the web. Unless otherwise indicated, the term xe2x80x9ctensile strengthxe2x80x9d means xe2x80x9cgeometric mean tensile strength.xe2x80x9d The basesheets of this invention preferably have a wet:dry ratio of about 0.1 or greater, more specifically about 0.15 or greater, more specifically about 0.2 or greater, still more specifically about 0.3 or greater, and still more specifically about 0.4 or greater, and still more specifically from about 0.2 to about 0.6. Tensile strengths can be measured using an Instron tensile tester using a 3-inch jaw width, a jaw span of 4 inches, and a crosshead speed of 10 inches per minute after maintaining the sample under TAPPI conditions for 4 hours before testing. For enhanced wet resiliency and integrity, the basesheets of this invention also preferably have a minimum absolute ratio of dry tensile strength to basis weight of about 1 gram/gsm, preferably from about 2 grams/gsm, more preferably about 5 grams/gsm, more preferably about 10 grams/gsm and still more preferably about 20 grams/gsm and preferably from about 15 to 50 grams/gsm.
xe2x80x9cOverall Surface Depthxe2x80x9d. A three-dimensional basesheet or web is a sheet with significant variation in surface elevation due to the intrinsic structure of the sheet itself. As used herein, this elevation difference is expressed as the xe2x80x9cOverall Surface Depth.xe2x80x9d The basesheets useful for this invention possess three-dimensionality and have an Overall Surface Depth of about 0.1 mm. or greater, more specifically about 0.3 mm. or greater, still more specifically about 0.4 mm. or greater, still more specifically about 0.5 mm. or greater, and still more specifically from about 0.4 to about 0.8 mm.
The three-dimensional structure of a largely planar sheet can be described in terms of its surface topography. Rather than presenting a nearly flat surface, as is typical of conventional paper, the molded sheets useful in producing the present invention have significant topographical structures that, in one embodiment, may derive in part from the use of sculptured through-drying fabrics such as those taught by Chiu et al. in U.S. Pat. No. 5,429,686, previously incorporated by reference. The resulting basesheet surface topography typically comprises a regular repeating unit cell that is typically a parallelogram with sides between 2 and 20 mm in length. For wetlaid materials, it is preferred that these three-dimensional basesheet structures be created by molding the moist sheet or be created prior to drying, rather than by creping or embossing or other operations after the sheet has been dried. In this manner, the three-dimensional basesheet structure is more likely to be well-retained upon wetting, helping to provide high wet resiliency and to promote good in-plane permeability. For air-laid basesheets, the structure may be imparted by thermal embossing of a fibrous mat with binder fibers that are activated by heat. For example, an air-laid fibrous mat containing thermoplastic or hotmelt binder fibers may be heated and then embossed before the structure cools to permanently give the sheet a three-dimensional structure.
In addition to the regular geometrical structure imparted by the sculptured fabrics and other fabrics used in creating a basesheet, additional fine structure, with an in-plane length scale less than about 1 mm, can be present in the basesheet. Such a fine structure can stem from microfolds created during differential velocity transfer of the web from one fabric or wire to another prior to drying. Some of the materials of the present invention, for example, appear to have fine structure with a fine surface depth of 0.1 mm or greater, and sometimes 0.2 mm or greater, when height profiles are measured using a commercial moirxc3xa9 interferometer system. These fine peaks have a typical half-width less than 1 mm. The fine structure from differential velocity transfer and other treatments may be useful in providing additional softness, flexibility, and bulk. Measurement of the surface structures is described below.
An especially suitable method for measurement of Overall Surface Depth is moirxc3xa9 interferometry, which permits accurate measurement without deformation of the surface. For reference to the materials of the present invention, surface topography should be measured using a computer-controlled white-light field-shifted moirxc3xa9 interferometer with about a 38 mm field of view. The principles of a useful implementation of such a system are described in Bieman et al. (L. Bieman, K. Harding, and A. Boehnlein, xe2x80x9cAbsolute Measurement Using Field-Shifted Moirxc3xa9,xe2x80x9d SPIE Optical Conference Proceedings, Vol. 1614, pp. 259-264, 1991). A suitable commercial instrument for moirxc3xa9 interferometry is the CADEYES(copyright) interferometer produced by Medar, Inc. (Farmington Hills, Michigan), constructed for a 38-mm field-of-view (a field of view within the range of 37 to 39.5 mm is adequate). The CADEYES(copyright) system uses white light which is projected through a grid to project fine black lines onto the sample surface. The surface is viewed through a similar grid, creating moirxc3xa9 fringes that are viewed by a CCD camera. Suitable lenses and a stepper motor adjust the optical configuration for field shifting (a technique described below). A video processor sends captured fringe images to a PC computer for processing, allowing details of surface height to be back-calculated from the fringe patterns viewed by the video camera.
In the CADEYES moirxc3xa9 interferometry system, each pixel in the CCD video image is said to belong to a moirxc3xa9 fringe that is associated with a particular height range. The method of field-shifting, as described by Bieman et al. (L. Bieman, K. Harding, and A. Boehnlein, xe2x80x9cAbsolute Measurement Using Field-Shifted Moirxc3xa9,xe2x80x9d SPIE Optical Conference Proceedings, Vol. 1614, pp. 259-264, 1991) and as originally patented by Boehnlein (U.S. Pat. No. 5,069,548, herein incorporated by reference), is used to identify the fringe number for each point in the video image (indicating which fringe a point belongs to). The fringe number is needed to determine the absolute height at the measurement point relative to a reference plane. A field-shifting technique (sometimes termed phase-shifting in the art) is also used for sub-fringe analysis (accurate determination of the height of the measurement point within the height range occupied by its fringe). These field-shifting methods coupled with a camera-based interferometry approach allows accurate and rapid absolute height measurement, permitting measurement to be made in spite of possible height discontinuities in the surface. The technique allows absolute height of each of the roughly 250,000 discrete points (pixels) on the sample surface to be obtained, if suitable optics, video hardware, data acquisition equipment, and software are used that incorporates the principles of moirxc3xa9 interferometry with field-shifting. Each point measured has a resolution of approximately 1.5 microns in its height measurement.
The computerized interferometer system is used to acquire topographical data and then to generate a grayscale image of the topographical data, said image to be hereinafter called xe2x80x9cthe height map.xe2x80x9d The height map is displayed on a computer monitor, typically in 256 shades of gray and is quantitatively based on the topographical data obtained for the sample being measured. The resulting height map for the 38-mm square measurement area should contain approximately 250,000 data points corresponding to approximately 500 pixels in both the horizontal and vertical directions of the displayed height map. The pixel dimensions of the height map are based on a 512xc3x97512 CCD camera which provides images of moirxc3xa9 patterns on the sample which can be analyzed by computer software. Each pixel in the height map represents a height measurement at the corresponding x- and y-location on the sample. In the recommended system, each pixel has a width of approximately 70 microns, i.e. represents a region on the sample surface about 70 microns long in both orthogonal in-plane directions). This level of resolution prevents single fibers projecting above the surface from having a significant effect on the surface height measurement. The z-direction height measurement must have a nominal accuracy of less than 2 microns and a z-direction range of at least 1.5 mm. (For further background on the measurement method, see the CADEYES Product Guide, Medar, Inc., Farmington Hills, Mich., 1994, or other CADEYES manuals and publications of Medar, Inc.)
The CADEYES system can measure up to 8 moirxc3xa9 fringes, with each fringe being divided into 256 depth counts (sub-fringe height increments, the smallest resolvable height difference). There will be 2048 height counts over the measurement range. This determines the total z-direction range, which is approximately 3 mm in the 38-mm field-of-view instrument. If the height variation in the field of view covers more than eight fringes, a wrap-around effect occurs, in which the ninth fringe is labeled as if it were the first fringe and the tenth fringe is labeled as the second, etc. In other words, the measured height will be shifted by 2048 depth counts. Accurate measurement is limited to the main field of 8 fringes.
The moirxc3xa9 interferometer system, once installed and factory calibrated to provide the accuracy and z-direction range stated above, can provide accurate topographical data for materials such as paper towels. (Those skilled in the art may confirm the accuracy of factory calibration by performing measurements on surfaces with known dimensions.) Tests are performed in a room under Tappi conditions (73xc2x0 F., 50% relative humidity). The sample must be placed flat on a surface lying aligned or nearly aligned with the measurement plane of the instrument and should be at such a height that both the lowest and highest regions of interest are within the measurement region of the instrument.
Once properly placed, data acquisition is initiated using Medar""s PC software and a height map of 250,000 data points is acquired and displayed, typically within 30 seconds from the time data acquisition was initiated. (Using the CADEYES(copyright) system, the xe2x80x9ccontrast threshold levelxe2x80x9d for noise rejection is set to 1, providing some noise rejection without excessive rejection of data points.) Data reduction and display are achieved using CADEYES(copyright) software for PCs, which incorporates a customizable interface based on Microsoft Visual Basic Professional for Windows (version 3.0). The Visual Basic interface allows users to add custom analysis tools.
The height map of the topographical data can then be used by those skilled in the art to identify characteristic unit cell structures (in the case of structures created by fabric patterns; these are typically parallelograms arranged like tiles to cover a larger two-dimensional area) and to measure the typical peak to valley depth of such structures. A simple method of doing this is to extract two-dimensional height profiles from lines drawn on the topographical height map which pass through the highest and lowest areas of the unit cells. These height profiles can then be analyzed for the peak to valley distance, if the profiles are taken from a sheet or portion of the sheet that was lying relatively flat when measured. To eliminate the effect of occasional optical noise and possible outliers, the highest 10% and the lowest 10% of the profile should be excluded, and the height range of the remaining points is taken as the surface depth. Technically, the procedure requires calculating the variable which we term xe2x80x9cP10,xe2x80x9d defined at the height difference between the 10% and 90% material lines, with the concept of material lines being well known in the art, as explained by L. Mummery, in Surface Texture Analysis: The Handbook, Hommelwerke GmbH, Mxc3xchlhausen, Germany, 1990. In this approach, which will be illustrated with respect to FIG. 7, the surface 31 is viewed as a transition from air 32 to material 33. For a given profile 30, taken from a flat-lying sheet, the greatest height at which the surface beginsxe2x80x94the height of the highest peakxe2x80x94is the elevation of the xe2x80x9c0% reference linexe2x80x9d 34 or the xe2x80x9c0% material line,xe2x80x9d meaning that 0% of the length of the horizontal line at that height is occupied by material. Along the horizontal line passing through the lowest point of the profile, 100% of the line is occupied by material, making that line the xe2x80x9c100% material linexe2x80x9d 35. In between the 0% and 100% material lines (between the maximum and minimum points of the profile), the fraction of horizontal line length occupied by material will increase monotonically as the line elevation is decreased. The material ratio curve 36 gives the relationship between material fraction along a horizontal line passing through the profile and the height of the line. The material ratio curve is also the cumulative height distribution of a profile. (A more accurate term might be xe2x80x9cmaterial fraction curve.xe2x80x9d)
Once the material ratio curve is established, one can use it to define a characteristic peak height of the profile. The P10 xe2x80x9ctypical peak-to-valley heightxe2x80x9d parameter is defined as the difference 37 between the heights of the 10% material line 38 and the 90% material line 39. This parameter is relatively robust in that outliers or unusual excursions from the typical profile structure have little influence on the P10 height. The units of P10 are mm. The Overall Surface Depth of a material is reported as the P10 surface depth value for profile lines encompassing the height extremes of the typical unit cell of that surface. xe2x80x9cFine surface depthxe2x80x9d is the P10 value for a profile taken along a plateau region of the surface which is relatively uniform in height relative to profiles encompassing a maxima and minima of the unit cells. Measurements are reported for the most textured side of the basesheets of the present invention, which is typically the side that was in contact with the through-drying fabric when air flow is toward the through-dryer. FIG. 8 represents a profile of Example 13 of the present invention, discussed below, having an Overall Surface Depth of about 0.5.
Overall Surface Depth is intended to examine the topography produced in the basesheet, especially those features created in the sheet prior to and during drying processes, but is intended to exclude xe2x80x9cartificiallyxe2x80x9d created large-scale topography from dry converting operations such as embossing, perforating, pleating, etc. Therefore, the profiles examined should be taken from unembossed regions if the basesheet has been embossed, or should be measured on an unembossed basesheet. Overall Surface Depth measurements should exclude large-scale structures such as pleats or folds which do not reflect the three-dimensional nature of the original basesheet itself. It is recognized that sheet topography may be reduced by calendering and other operations which affect the entire basesheet. Overall Surface Depth measurement can be appropriately performed on a calendered basesheet.
The xe2x80x9cWet Wrinkle Recovery Testxe2x80x9d is a slight modification of AATCC Test Method 66-1990 taken from the Technical Manual of the American Association of Textile Chemists and Colorists (1992), page 99. The modification is to first wet the samples before carrying out the method. This is done by soaking the samples in water containing 0.01 percent TRITON X-100 wetting agent (Rohm and Haas) for five minutes before testing. Sample preparation is carried out at 73xc2x0 F. and 50 percent relative humidity. The sample is gently removed from the water with a tweezers, drained by pressing between two pieces of blotter paper with 325 grams of weight, and placed in the sample holder to be tested as with the dry wrinkle recovery test method. The test measures the highest recovery angle of the sample being tested (in any direction, including the machine direction and the cross-machine direction), with 180xc2x0 representing total recovery. The Wet Wrinkle Recovery, expressed as a percent recovery, is the measured recovery angle divided by 180xc2x0, multiplied by 100. Basesheets of this invention can exhibit a Wet Wrinkle Recovery of about 60 percent or greater, more specifically about 70 percent or greater, and still more specifically about 80 percent or greater.
xe2x80x9cWet compressive resiliencyxe2x80x9d of the basesheets is defined by several parameters and can be demonstrated using a materials property procedure that encompasses both wet and dry characteristics. A programmable strength measurement device is used in compression mode to impart a specified series of compression cycles to an initially dry, conditioned sample, after which the sample is carefully moistened in a specified manner and subjected to the same sequence of compression cycles. While the comparison of wet and dry properties is of general interest, the most important information from this test concerns the wet properties. The initial testing of the dry sample can be viewed as a conditioning step. The test sequence begins with compression of the dry sample to 0.025 psi to obtain an initial thickness (cycle A), then two repetitions of loading up to 2 psi followed by unloading (cycles B and C). Finally, the sample is again compressed to 0.025 psi to obtain a final thickness (cycle D). (Details of the procedure, including compression speeds, are given below). Following the treatment of the dry sample, moisture is applied uniformly to the sample using a fine mist of deionized water to bring the moisture ratio (g water/g dry fiber) to approximately 1.1. This is done by applying 95-110% added moisture, based on the conditioned sample mass. This puts typical cellulosic materials in a moisture range where physical properties are relatively insensitive to moisture content (e.g., the sensitivity is much less than it is for moisture ratios less than 70%). The moistened sample is then placed in the test device and the compression cycles are repeated.
Three measures of wet resiliency are considered which are relatively insensitive to the number of sample layers used in the stack. The first measure is the bulk of the wet sample at 2 psi. This is referred to as the xe2x80x9cWet Compressed Bulkxe2x80x9d (WCB). The second measure is termed xe2x80x9cWet Springback Ratioxe2x80x9d (WS), which is the ratio of the moist sample thickness at 0.025 psi at the end of the compression test (cycle D) to the thickness of the moist sample at 0.025 psi measured at the beginning of the test (cycle A). The third measure is the xe2x80x9cLoadinq Energy Ratioxe2x80x9d (LER), which is the ratio of loading energy in the second compression to 2 psi (cycle C) to that of the first compression to 2 psi (cycle B) during the sequence described above, for a wetted sample. The final wet bulk measured at the end of the test (at 0.025 psi) is termed the xe2x80x9cfinal bulkxe2x80x9d or xe2x80x9cFBxe2x80x9d value. When load is plotted as a function of thickness, loading energy is the area under the curve as the sample goes from an unloaded state to the peak load of that cycle. For a purely elastic material, the springback and loading energy ratio would be unity. Applicants have found that the three measures described here are relatively independent of the number of layers in the stack and serve as useful measures of wet resiliency. Also referred to herein is the xe2x80x9cCompression Ratioxe2x80x9d, which is defined as the ratio of moistened sample thickness at peak load in the first compression cycle to 2 psi to the initial moistened thickness at 0.025 psi.
In carrying out the foregoing measurements of the wet compressive resiliency, samples should be conditioned for at least 24 hours under TAPPI conditions (50% RH, 73xc2x0 F.). Specimens are die cut to 2.5xe2x80x9cxc3x972.5xe2x80x9d squares. Conditioned sample weight should be near 0.4 g, if possible, and within the range of 0.25 to 0.6 g for meaningful comparisons. The target mass of 0.4 g is achieved by using a stack of 2 or more sheets if the sheet basis weight is less than 65 gsm. For example, for nominal 30 gsm sheets, a stack of 3 sheets will generally be near 0.4 g total mass.
Compression measurements are performed using an Instron 4502 Universal Testing Machine interfaced with a 286 PC computer running Instron Series XII software (1989 issue) and Version 2 firmware. The standard xe2x80x9c286 computerxe2x80x9d referred to has an 80286 processor with a 12 MHz clock speed. The particular computer used was a Compaq DeskPro 286e with an 80287 math coprocessor and a VGA video adapter. A 1 kN load cell is used with 2.25xe2x80x3 diameter circular platens for sample compression. The lower platen has a ball bearing assembly to allow exact alignment of the platens. The lower platen is locked in place while under load (30-100 lbf) by the upper platen to ensure parallel surfaces. The upper platen must also be locked in place with the standard ring nut to eliminate play in the upper platen as load is applied.
Following at-least one hour of warm-up after start-up, the instrument control panel is used to set the extensionometer to zero distance while the platens are in contact (at a load of 10-30 lb). With the upper platen freely suspended, the calibrated load cell is balanced to give a zero reading. The extensionometer and load cell should be periodically checked to prevent baseline. drift (shirting of the zero points). Measurements must be performed in a controlled humidity and temperature environment, according to TAPPI specifications (50%xc2x12% RH and 73xc2x0 F.). The upper platen is then raised to a height of 0.2 in. and control of the Instron is transferred to the computer.
Using the Instron Series XII Cyclic Test software with a 286 computer, an instrument sequence is established with 7 markers (discrete events) composed of 3 cyclic blocks (instructions sets) in the following order:
Marker 1: Block 1
Marker 2: Block 2
Marker 3: Block 3
Marker 4: Block 2
Marker 5: Block 3
Marker 6: Block 1
Marker 7: Block 3.
Block 1 instructs the crosshead to descend at 1.5 in./min. until a load of 0.1 lb. is applied (the Instron setting is xe2x88x920.1 lb., since compression is defined as negative force).
Control is by displacement. When the targeted load is reached, the applied load is reduced to zero.
Block 2 directs that the crosshead range from an applied load of 0.05 lb. to a peak of 8 lb. then back to 0.05 lb. at a speed of 0.4 in./min. Using the Instron software, the control mode is displacement, the limit type is load, the first level is xe2x88x920.05 lb., the second level is xe2x88x928 lb., the dwell time is 0 sec., and the number of transitions is 2 (compression, then relaxation); xe2x80x9cno actionxe2x80x9d is specified for the end of the block.
Block 3 uses displacement control and limit type to simply raise the crosshead to 0.2 in. at a speed of 4 in./min., with 0 dwell time. Other Instron software settings are 0 in first level, 0.2 in second level, 1 transition, and xe2x80x9cno actionxe2x80x9d at the end of the block.
When executed in the order given above (Markers 1-7), the Instron sequence compresses the sample to 0.025 psi (0.1 lbf), relaxes, then compresses to 2 psi (8 lbs.), followed by decompression and a crosshead rise to 0.2 in., then compress the sample again to 2 psi, relaxes, lifts the crosshead to 0.2 in., compresses again to 0.025 psi (0.1 lbf), and then raises the crosshead. Data logging should be performed at intervals no greater than every 0.02xe2x80x3 or 0.4 lb. (whichever comes first) for Block 2 and for intervals no greater than 0.01 lb. for Block 1. Preferably, data logging is performed every 0.004 lb. in Block 1 and every 0.05 lb. or 0.005 in. (whichever comes first) in Block 2.
The results output of the Series XII software is set to provide extension (thickness) at peak loads for Markers 1, 2, 4 and 6 (at each 0.025 and 2.0 psi peak load), the loading energy for Markers 2 and 4 (the two compressions to 2.0 psi previously termed cycles B and C, respectively), the ratio of the two loading energies (second cycle/first cycle), and the ratio of final thickness to initial thickness (ratio of thickness at last to first 0.025 psi compression). Load versus thickness results are plotted on the screen during execution of Blocks 1 and 2.
In performing a measurement, the dry, conditioned sample is centered on the lower platen and the test is initiated. Following completion of the sequence, the sample is immediately removed and moisture (deionized water at 72-73xc2x0 F.) is applied. Moisture is applied uniformly with a fine mist to reach a moist sample mass of approximately 2.0 times the initial sample mass (95-110% added moisture is applied, preferably 100% added moisture, based on conditioned sample mass; this level of moisture should yield an absolute moisture ratio of about 1.1 g. water/g. oven dry fiberxe2x80x94with oven dry referring to drying for at least 30 minutes in an oven at 105xc2x0 C.). (For the uncreped throughdried materials of this invention, the moisture ratio could be within the range of 1.05 to 1.7 without significantly affecting the results). The mist should be applied uniformly to separated sheets (for stacks of more than 1 sheet), with spray applied to both front and back of each sheet to ensure uniform moisture application. This can be achieved using a conventional plastic spray bottle, with a container or other barrier blocking most of the spray, allowing only about the upper 10-20% of the spray envelopexe2x80x94a fine mistxe2x80x94to approach the sample. The spray source should be at least 10xe2x80x3 away from the sample during spray application. In general, care must be applied to ensure that the sample is uniformly moistened by a fine spray. The sample must be weighed several times during the process of applying moisture to reach the targeted moisture content. No more than three minutes should elapse between the completion of the compression test on the dry sample and the completion of moisture application. Allow 45-60 seconds from the final application of spray to the beginning of the subsequent compression test to provide time for internal wicking and absorption of the spray. Between three and four minutes will elapse between the completion of the dry compression sequence and initiation of the wet compression sequence.
Once the desired mass range has been reached, as indicated by a digital balance, the sample is centered on the lower Instron platen and the test sequence is initiated. Following the measurement, the sample is placed in a 105xc2x0 C. oven for drying, and the oven dry weight will be recorded later (sample should be allowed to dry for 30-60 minutes, after which the dry weight is measured).
Note that creep recovery can occur between the two compression cycles to 2 psi, so the time between the cycles may be important. For the instrument settings used in these Instron tests, there is a 30 second period (xc2x14 sec.) between the beginning of compression during the two cycles to 2 psi. The beginning of compression is defined as the point at which the load cell reading exceeds 0.03 lb. Likewise, there is a 5-8 second interval between the beginning of compression in the first thickness measurement (ramp to 0.025 psi) and the beginning of the subsequent compression cycle to 2 psi. The interval between the beginning of the second compression cycle to 2 psi and the beginning of compression for the final thickness measurement is approximately 20 seconds.
The utility of a web or absorbent structure having a high Wet Compressed Bulk (WCB) value is obvious, for a wet material which can maintain high bulk under compression can maintain higher fluid capacity and is less likely to allow fluid to be squeezed out when it is compressed.
High Wet Springback Ratio values are especially desirable because a wet material that springs back after compression can maintain high pore volume for effective intake and distribution of subsequent insults of fluid, and such a material can regain fluid during its expansion which may have been expelled during compression. In diapers, for example, a wet region may be momentarily compressed by body motion or changes in body position. If the material is unable to regain its bulk when the compressive force is released, its effectiveness for handling fluid is reduced.
High Loading Energy Ratio values in a material are also useful, for such a material continues to resist compression (LER is based on a measure of the energy required to compress a sample) at loads less than the peak load of 2 psi, even after it has been heavily compressed once. Maintaining such wet elastic properties is believed to contribute to the feel of the material when used in absorbent articles, and may help maintain the fit of the absorbent article against the wearer""s body, in addition to the general advantages accrued when a structure can maintain its pore volume when wet.
The hydrophobically-treated absorbent webs of this invention and the untreated, inherently hydrophilic basesheets useful in producing this invention can exhibit one or more of the foregoing properties. More specifically, said absorbent webs and basesheets can have a Wet Compressed Bulk of about 6 cubic centimeters per gram or greater, more specifically about 7 cubic centimeters per gram or greater, more specifically about 8 cubic centimeters per gram or greater, and still more specifically from about 8 to about 13 cubic centimeters per gram. The Compression Ratio can be about 0.7 or less, more specifically about 0.6 or less, still more specifically about 0.5 or less, and still more specifically from 0.4 to about 0.7. Also, they can have a Wet Springback Ratio of about 0.6 or greater, more specifically about 0.7 or greater, more specifically about 0.85, and still more specifically from about 0.8 to about 0.93. The Loading Energy Ratio can be about 0.6 or greater, more specifically 0.7 or greater, more specifically still about 0.8 or greater, and most specifically from about 0.75 to about 0.9. Final bulk can be about 8 cubic centimeters per gram or greater or preferably about 12 centimeters per gram or greater.
xe2x80x9cIn-Plane Permeabilityxe2x80x9d. An important property of porous media, particularly for absorbent products, is the permeability to liquid flow. The complex, interconnected pathways between the solid particles and boundaries of a porous media provide routes for fluid flow which may offer significant flow resistance due to the narrowness of the channels and the tortuosity of the pathways.
For paper, permeability is commonly expressed in terms of gas flow rates through a sheet. This practice is useful for comparing similar sheets, but does not truly characterize the interaction of flowing fluid with the porous structure and provides no direct information about flow in a wet sheet. The standard engineering definition of permeability provides a more useful parameter, though one less easily measured. The standard definition is based on Darcy""s law (see F. A. L. Dullien, Porous Media: Fluid Transport and Pore Structure, Academic Press, New York, 1979), which, for one-dimensional flow, states that the velocity of fluid flow through a saturated porous medium is directly proportional to the pressure gradient: V = K μ Δ xe2x80x83 P L ( 1 )
where V is the superficial velocity (flow rate divided by area), K is the permeability, xcexc is the fluid viscosity, and xcex94P is the pressure drop in the flow direction across a distance L. The units of K are m2. In Equation (1), the permeability is an empirical proportionality parameter linking fluid velocity to pressure drop and viscosity. For a homogeneous medium, K is not a function of xcex94P, sample length, or viscosity, but is an intrinsic parameter describing the flow resistance of the medium. In a compressible medium, permeability will be a function of the degree of compression. Darcian permeability is a fundamental parameter for processes involving fluid flow in fibrous webs.
Darcian permeability has units of area (m2) and for simple uniform cylindrical pores is proportional to the cross sectional area of a single pore. However, the permeability of most real materials cannot be predicted from an optical assessment of pore size. Permeability is determined not only by pore size, but also pore orientation, tortuosity, and interconnectedness. Large pores in the body of an object may be inaccessible to fluid flow or accessible only through minute pores offering high flow resistance. Even with a full three-dimensional description of the pore space of a material from x-ray tomography or other imaging techniques, it is difficult to predict or calculate the permeability. Permeability and pore size determinations are related but distinct pieces of information about a material. For example, a sheet of metal with discreet, nonoverlapping holes punched in it may have very large pores (the holes), while still having negligible In-Plane Permeability. Swiss cheese has many large pores, but typically has negligible permeability in any direction unless sliced so thin that individual holes can extend from one face to the other of the cheese sample.
Most studies of permeability in paper have focused on flow in the z-direction (normal to the plane of the sheet), which is of practical importance in wet pressing and other unit operations. However, paper is an anisotropic material (for example, see E. L. Back, xe2x80x9cThe Pore Anisotropy of Paper Products and Fibre Building Boards,xe2x80x9d Svensk Papperstidning, 69: 219 (1966)), meaning that fluid flow properties are a function of direction. In this case, different flow directions will appear to have different apparent permeabilities. The many possibilities of flow direction and pressure gradients in such a medium can be encompassed with a multidimensional form of Darcy""s law, v _ = - K _ _ · ∇ P μ , ( 2 )
where {overscore (v)} is the superficial velocity vector (volumetric flow rate divided by cross-sectional area of the flow), xcexc is the viscosity of the fluid, {double overscore (K)} is a second-order tensor and ∇P is the pressure gradient. If a Cartesian coordinate system is chosen to correspond with the principal flow directions of the porous medium, then the permeability tensor becomes a diagonal matrix (see Jacob Bear, xe2x80x9cDynamics of Fluids in Porous Media.,xe2x80x9d American Elsevier, New York, N.Y., 1972, pp. 136-151): K _ _ = [ K x 0 0 0 K y 0 0 0 K z ] , ( 3 )
where Kx, Ky, and Kz are the principal permeability components in the x-, y-, and z-directions, respectively. In paper, these directions will generally correspond to the cross-direction (taken here as y) and the machine-direction (taken as x, the direction of maximum In-Plane Permeability) in the plane, and the transverse or thickness direction (z). Thus, the anisotropic permeability of typical machine-made paper can be characterized with three permeability parameters, one for the machine-direction, one for the cross-direction, and one for the z-direction. (In some cases, as when there are unbalanced flows in the headbox of the paper machine, the direction of maximum permeability may be slightly off from the machine direction; the direction of maximum In-Plane Permeability and the direction orthogonal to that should be used for the x- and y-directions, respectively, in that case.) In handsheets, there may be no preferential direction of orientation for fibers lying in the plane, so the x- and y-direction permeability values should be equal (in other words, such a sheet is isotropic in the plane).
In spite of the past focus on z-direction permeability in paper, In-Plane Permeability (both Kx and Ky are in-plane factors) is important in a variety of applications, especially in absorbent articles. Body fluids or other liquids flowing into the absorbent article usually enter the article in a narrow, localized region. Efficient use of the absorbent medium requires that the incoming fluid be distributed laterally through in-plane flow in the absorbent article, otherwise the local capacity of the article to handle the incoming liquid may be overwhelmed resulting in leakage and poor utilization of the absorbent core. The ability of fluid to flow in the plane of the article is a function of the driving force for fluid flow, which can be a combination of capillary wicking and hydraulic pressure from fluid source, and of the ability of the porous medium to conduct flow, which is described in large part by the Darcian permeability of the material. Two-phase flow and non-Newtonian liquids or suspensions complicate the physics, but the in-plane permeability of the porous medium is a critical factor for rapid in-plane distribution of liquid insults. Especially in the case of urine management, where liquid flow rates may occur far in excess of the ability of capillary forces, high In-Plane Permeability is needed in the intake layer to allow the fluid to be distributed laterally rather than to leak.
While many past studies of liquid permeability in paper focused exclusively on measuring Kz for z-direction flow, more recently, methods have been taught for measuring permeability in the plane of a paper sheet. J. D. Lindsay and P. H. Brady teach methods for in-plane and z-direction permeability measurements of saturated paper in xe2x80x9cStudies of Anisotropic Permeability with Applications to Water Removal in Fibrous Webs: Part I,xe2x80x9d Tappi J., 76(9): 119-127 (1993) and xe2x80x9cStudies of Anisotropic Permeability with Applications to Water Removal in Fibrous Webs: Part II,xe2x80x9d Tappi J., 76(11): 167-174 (1993). Related methods have been published by K. L. Adams, B. Miller, and L. Rebenfeld in xe2x80x9cForced In-Plane Flow of an Epoxy Resin in Fibrous Networks,xe2x80x9d Polymer Engineering and Science, 26(20): 1434-1441 (1986); J. D. Lindsay in xe2x80x9cRelative Flow Porosity in Fibrous Media: Measurements and Analysis, Including Dispersion Effects,xe2x80x9d Tappi J., 77(6): 225-239 (June 1994); J. D. Lindsay and J. R. Wallin, xe2x80x9cCharacterization of In-Plane Flow in Paper,xe2x80x9d AlChE 1989 and 1990 Forest Products Symposium, Tappi Press, Atlanta, Ga. (1992), p. 121; and D. H. Horstmann, J. D. Lindsay, and R. A. Stratton, xe2x80x9cUsing Edge-Flow Tests to Examine the In-Plane Anisotropic Permeability of Paper,xe2x80x9d Tappi J., 74(4): 241 (1991).
The basic method used in most of these publications is injection of fluid into the center of a paper disk that is constrained between two flat surfaces to force the fluid flow to be in the radial direction, proceeding from the injection point at the center of the disk to the outer edge of the disk. This is illustrated in FIG. 9, which depicts a sheet 41 in which a central hole 42 has been punched and into which fluid is injected by means of an injection port of the same size as the punched hole. Fluid is forced to flow to the outer radial edge 43. For a liquid-saturated sheet of constant thickness subject to steady radial fluid flow in the manner described in the work of Lindsay and others, the equation relating average In-Plane Permeability to fluid flow is: K r ≡ K x + K y 2 = Q μ ln ( R o / R i ) 2 π xe2x80x83 L p Δ xe2x80x83 P , ( 4 )
where Ro is the radius of the paper disk 41, Ri is the radius of the central hole 42 in the sample into which fluid is injected through an injection port; Lp is the thickness of the paper; xcex94P is the constant pressure above atmospheric pressure at which fluid is injected into the disk (the gauge pressure at the injection pore); Q is the volumetric flow rate of liquid, and Kr is the In-Plane Permeability, technically the average radial permeability, defined as the average of the two in-plane permeability components. The disk diameter is 5 inches. The central inlet hole 42 was consistently 0.375 inches (xe2x85x9c inch) and was created using a paper punch tool. The test apparatus for In-Plane Permeability measurements is depicted in FIG. 10 and FIG. 11, which is similar in principle to the apparatus taught by Lindsay and Brady, previously cited. Tubing 45 connects water from a water reservoir to an injection port drilled into a 1-inch thick Plexiglas support plate 45. (The support plate is transparent to permit viewing of the wetted sample, especially in cases when an aqueous dye solution is injected into the sample. A mirror at a 45 degree angle below the support plate facilitates viewing and photography.) The water reservoir 51 provides a nearly constant hydraulic head 49 for fluid injection during the test. The volumetric flow rate is obtained by noting the change in water reservoir mass as a function of time, and converting the water mass flow rate to a volumetric flow rate. Vacuum-deaerated deionized water at room temperature is used.
In using the apparatus, a paper disk 41, cut to be 5-inches in diameter and having a central hole diameter of 0.375-inches, is placed on the support plate 46 over the injection port 44 (0.375 inches diameter also) and is then saturated with water. The fluid injection line 45 and the injection port 44 should be filled with water and efforts should be taken to avoid air bubbles being trapped in the sheet or in the injection area. To help eliminate air pockets, the sample 41 should be bent gently in the center as it is placed on the wet support plate to initiate liquid contact in the center of the sample; the edges can then be lowered gradually to create a wedge-like motion of the liquid meniscus to sweep air bubbles out from under the sheet. Multi-ply stacks of sheets can be handled in the same way, although preliminary sample wetting may be needed to remove interply air bubbles. The goal in removing air bubbles is to reduce the flow blockage that trapped air bubbles can cause.
Once the wetted sample is in place, a cylindrical metal platen 47, 5-inches in diameter, is gently lowered on top of the sample to provide a constant compressive load and to provide a reference surface on its top for thickness measurement with displacement gauges 48. Three displacement gauges 48 are used, spaced approximately evenly around the edge of the top of the metal cylinder 47, in order to measure the average thickness of the sheet 41. The sample thickness is taken as the average of the three displacement values relative to a zero point when no sample is present. A suitable thickness gauge is the Mitutoyo Digimatic Indicator, Model 543-525-1, with a 2-inch stroke (traveling distance of the contacting spindle) and a precision of 1 micrometer. The thickness gauges are rigidly mounted relative to the support plate. The contacting spindles of the thickness gauges can be raised and lowered (without changing the position of the body of the gauge) by use of a cable to provide clearance for moving the metal platen onto the sample. The small force applied by the thickness gauges 48 should be added to the weight of the metal platen 47 to obtain the total force applied to the sample 41; this force, when divided by the cross sectional area of the sample and platen, should be 0.8 psi.
A hydraulic head of 13 inches is used to drive the liquid flow. The head is the vertical distance 49 between the water line 50 of the supply reservoir 51 and the plane of the sample 41. This head is achieved by placement of a water bottle 51, filled to a specified level 50, on a mass balance 52 at a fixed height relative to the support plate 46 on which the sample rests. As the sample is being placed on the support plate, the water reservoir is at such a height that the water level 50 in the reservoir is nearly the same as (or slightly greater than) the support plate 46 on which the sample rests. When the sample has been moistened and placed under the compressive load of the metal platen, the water reservoir is then raised and placed on a mass balance 52 such that the water level is 13 inches above the support platen. A timer is activated and the water reservoir mass is recorded at 20 seconds or 30 seconds intervals for a least 90 seconds. The thickness readings of the three gauges is also recorded regularly during the test. To reduce creep, the saturated sample should be allowed to equilibrate under the compressive load for at least 30 seconds before the water bottle is raised and forced flow through the sample begins.
The change in water reservoir mass as a function of time gives the mass flow rate, which can easily be converted to a volumetric flow rate for use in Equation 4. Normal engineering principles should be used to ensure that the proper units (preferably SI units) are used in applying Equation 4.
In performing In-Plane Permeability measurements, it is important that the sample be uniformly compressed against the restraining surfaces to prevent large channels or openings that would provide paths of least resistance for substantial liquid flow that could bypass much of the sample itself. Ideally, the liquid will flow uniformly through the sample, and this can be ascertained by injecting dyed fluid into the sample and observing the shape of the dyed region through the transparent support plate. Injected dye should spread out uniformly from the injection point. In isotropic samples, the shape of the moving dye region should be nearly circular. In materials with in-plane anisotropy due to fiber orientation or small-scale structural orientation, the shape of the dye region should be oval or elliptical, and nearly symmetric about the injection point. A suitable dye for such tests is Versatint Purple II made by Milliken Chemical Corp. (Inman, S.C.). This is a fugitive dye that does not absorb onto cellulose, allowing for easy visualization of liquid flow through the fibrous medium.
As will be illustrated in the Examples, the webs and basesheets of this invention possess very high In-Plane Permeability. The In-Plane Permeability can be about 0.1xc3x9710xe2x88x9210 square meters or greater, more specifically about 0.3xc3x9710xe2x88x9210 square meters or greater, more specifically about 0.5xc3x9710xe2x88x9210 square meters or greater, still more specifically from about 0.5xc3x971010 to about 8xc3x9710xe2x88x9210 square meters, and still more specifically from about 0.8xc3x9710xe2x88x9210 to about 5xc3x9710xe2x88x9210 square meters. | {
"pile_set_name": "USPTO Backgrounds"
} |
Machine type communication (MTC) has been discussed in the 3GPP standard. For MTC applications of certain types, a terminal with ultra-low power consumption and a corresponding communication method are crucial.
In the current society, there is such a need, for example, for a children mobile phone, to inquire the location of a child. However, in case of emergency, the mobile phone may not always be recharged in time after running out of battery. Therefore, in this case a terminal with ultra-low power consumption is needed to periodically notify (or to be triggered to notify) a wireless network and it can work for a very long time to transfer key information, such as a specific location or “I am alive”. By using such a communication method, the wireless network can track the status of the terminal for a long time.
The challenge to MTC terminals of this type is to have a battery life that is several years long. For reference, the longest standby time of an existing terminal is just several months.
Power consumption of a terminal may be divided into several parts:
power consumption of the terminal in an idle state, which is determined by a power saving technology of the terminal, for example, design of a chip with an ultra-low leakage current;
power consumption of the terminal to synchronize and obtain information broadcast by a cell;
power consumption of the terminal to intercept common control channel information (for example, paging information or scheduling information);
power consumption of the terminal to transmit uplink data; and
power consumption of the terminal to receive downlink data.
FIG. 1A and FIG. 1B depict a process of GPRS (General Packet Radio Service) data transmission. As can be seen from FIG. 1A and FIG. 1B. This process includes transmission of lots of uplink signaling data and reception of lots of downlink signaling data. If an existing communication method is used, the longest battery life of the MTC terminal will not be more than half a year, and it is very difficult to further reduce power consumption of the MTC terminal. | {
"pile_set_name": "USPTO Backgrounds"
} |
a. Field of the Invention
This invention relates to a novel hydroxycarboxylic acid resin, and also to its production process and use. The hydroxycarboxylic acid resin according to the present invention is useful inter alia as a photoresist resin composition with excellent sensitivity and resolving power, as a metal chelate resin with excellent flexibility, oxidation resistance and waterproofness, as a color-developing agent for pressure-sensitive copying paper or an intermediate therefor, and as an epoxy resin curing agent.
b. Description of the Related Art
As photoresist resins, phenol or cresol novolak resins are used in general. A composition formed of a diazidonaphthoquinonesulfonate and a novolak resin is used as a positive resist, because when exposed to light of 300-500 nm, quinone diazide groups are decomposed into carboxyl groups and the diazidonaphthoquinonesulfonate is hence converted from the alkaline-solution-insoluble form into an alkaline-solution-soluble form. This positive resist features far superior resolving power to negative resists and is used for the fabrication of integrated circuits such as ICs and ISIs. With respect to integrated circuits, miniaturization has progressed in recent years, keeping step with the high densification, so that formation of patterns on the order of submicrons is now demanded. As a result, still better resolving power is required even for positive resists. In the case of a resist material formed of a diazidonaphthoquinonesulfonate and a novolak resin, there is a limitation to the improvement of the resolving power as long as conventional available materials are combined. An improvement in resolving power might be contemplated, for example, by increasing the content of the quinone diazide compound. An increase in the content of the quinone diazide compound however is accompanied by serious drawbacks such as a reduction in sensitivity and an increase in development residue. There is hence a limitation to the improvement of the resolving power, resulting in the demand for a base resin as a substitute for phenol or cresol novolak resins.
There have also been attempts to improve the sensitivity and developability of a resist composition by adding a specific compound thereto. For example, Japanese Patent Laid-Open No. 141441/1986 discloses a positive composition containing trihydroxybenzophenone. A problem with this trihydroxybenzophenone-containing positive photoresist however is that the heat resistance is deteriorated by the addition of trihydroxybenzophenone, although the sensitivity and developability have been improved. Further, Japanese Patent Laid-Open Nos. 44439/1989, 177032/1989, 280748/1989 and 10350/1990 disclose techniques for increasing the sensitivity without reducing the heat resistance by the addition of aromatic polyhydroxy compounds other than trihydroxybenzophenone. However, these techniques are not considered to be sufficient with respect to the improvement of developability.
On the other hand, salicylic acid novolak resins have already been known as metal chelate resins, cement dispersants, metal coating thickeners, fiber treatments, color-developing materials for pressure-sensitive copying paper, and the like. Resins of this type are each produced by reacting salicylic acid with formaldehyde in the presence of an acid catalyst [for example, Journal of Organic Chemistry (J. Org. Chem.), 27, 1424(1962); publications in which the former publication is referred to.]. Further, Japanese Patent Laid-Open Nos. 164716/1987 and 176875/1987 disclose novel salicylic acid resins, i.e., xylok resins. Like novolak resins represented by phenol-formaldehyde resin, however, salicylic acid novolak resins are accompanied by such drawbacks as low flexibility and susceptibility to oxidation and deterioration. To meet the high physical properties required in recent years, there is increasing recognition that improvements to the resins themselves are indispensable. Further, the salicylic-acid-base xylok resins are accompanied by the drawback that they have low waterproofness. | {
"pile_set_name": "USPTO Backgrounds"
} |
At present, DSL technologies have been widely applied, and requirements on the DSL subscriber board also rise continuously. Port density of a subscriber board is increasing from 8, 16, 32 to 64, or even higher, and DSL line bandwidth is increasing from 512 k, 2 M, 8 M, 24 M to as high as 100 M. To accord with the above developing trend, processing bandwidth of the DSL subscriber board must be increased quickly.
A structure of most DSL subscriber boards is shown in FIG. 1. There is only one interface (interface 1) between a DSL physical interface chip and a protocol processing chip. Generally, the interface 1 can be a Universal Test and Operations PHY Interface for ATM (UTOPIA) Level 1 (a first class of interface), or a UTOPIA Level 2 (a second class of interface), or a Packet over SONET/SDH (POS) Level 1 interface or a POS Level 2 interface. And there is only one uplink interface (interface 2) between the protocol processing chip and an uplink physical interface chip. The form of the interface 2 is not limited. Generally, it can be a Gigabyte Ethernet (GE) interface, a Fast Ethernet (FE) interface or a Low Voltage Difference Synchronization (LVDS) interface. Alternatively, the interface 2 can also be implemented by two interfaces which operate as work/backup interfaces, and only one of the two interfaces works at the same time.
Therefore, a method for increasing the bandwidth of a DSL subscriber board is required. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Technical Field
The present invention relates to novel monoclonal antibodies which may be used in the detection of Human Immunodeficiency Virus (HIV). These antibodies exhibit an unusually high degree of sensitivity, a remarkably broad range of specificity, and bind to novel shared, non-cross-reactive epitopes. In particular, the monoclonal antibodies of the present invention may be utilized to detect HIV-1 antigen and HIV-2 core antigen in a patient sample.
2. Background Information
Acquired Immunodeficiency Syndrome (AIDS) is an infectious and incurable disease transmitted through sexual contact from HIV infected individuals or by exposure to HIV contaminated blood or blood products. HIV-1 includes the formerly named viruses Human T-cell Lymphotrophic Virus Type III (HTLV III), Lymphadenopathy Associated Virus (LAV), and AIDS Associated Retrovirus (ARV). HIV is a retrovirus related to a group of cytopathic retroviruses, namely lentiviruses, on the basis of morphologic features, genomic organization, and nucleotide sequence (Gonda et al., Science (1985) 277:177-179; Stephan et al., Science (1986) 231:589-594; Korber, B. (ed.) et al., Human Retroviruses and AIDS. A Compilation and Analysis of Nucleic Acid and Amino Acid Sequences. Published by Theoretical Biology and Biophysics, Los Alamos National Laboratory, Los Alamos, N. Mex.; Reviewed in, Schochetman, G. and George, J. R., (1994) AIDS Testing. Springer-Verlag, New York, Berlin, Heidelberg). HIV is an enveloped virus containing several structural proteins. Of particular relevance, the core of the virus is formed by condensation of cleavage products from a highly processed gag-pol polyprotein precursor (Pr180gag-pol) which is cleaved into a pol precursor and a gag precursor (Pr55gag). Subsequently, the core precursor Pr55gag is cleaved into p17 (myristilated gag protein), p24 (major structural protein), p7 (nucleic acid binding protein), and p9 (proline-rich protein). The envelope contains two structural proteins, gp120 (envelope glycoprotein) and gp41 (transmembrane protein) which are cleavage products of the envelope polyprotein precursor, gp160.
The most common markers of HIV infection are antibodies against viral structural proteins (Dawson, et.al., J. Infect. Dis. (1988) 157:149-155; Montagnier, et al. Virology (1985) 144:283-289; Barin, et al., Science (1985) 228:1094-1096; Schulz, T. F., et al., Lancet (1986) 2:111-112; Sarngadharan, et al., Science (1984) 224:506-508; Allan, et al., Science (1985) 228:1091-1093) and viremia in the form of detectable viral core antigen (antigenemia) (Kessler, et. al., JAMA (1987) 258:1196-1199; Phair, JAMA (1987) 258:p1218; Allain, et al., The Lancet (1986) ii:1233-1236; Kenny, et al., The Lancet (1987) 1 (8532):565-566; Wall, et al., The Lancet (1987) 1(8532):p566; Stute, The Lancet (1987) 1(8532):p566; Goudsmit, et al., The Lancet (1986) ii: 177-180; vonSydow, et al., Brit. Med. J. (1988) 296:238-240; Bowen, et al. Ann. of Int. Med. (1988) 108:46-48) or detectable viral nucleic acid (Mellors, et al., Science (1996) 272: 1167-1170; Saag, et al. Nat. Med. (1996) 2: 625-629; Mulder, et al. J. Clin. Microbiol. (1994) 32:292-300; Zhang, et al., AIDS (1991) 5(6):675-681; Simmonds, et al., J. Virology (1990) 64(2):864-872). For example, in the United States, screening of blood and blood products by tests to detect antibody or antigen is mandated (Federal Food, Drug, and Cosmetic Act, 21 U.S.C. 301 et. seq., Public Health Service Act 42 U.S.C. 201 et. seq.). Nucleic acid testing recently has been implemented in order to attain maximal reduction of the HIV seroconversion window (www.fda.gov). As a further example, various countries in Europe have begun to evaluate and use tests that detect antibody and antigen simultaneously (Ly, et al. J. Clin. Microbiol. (2000) 38(6): 2459-2461; Gurtler, et al., J. Virol. Methods (1998) 75: 27-38; Weber, et al., J. Clin. Microbiol (1998) 36(8): 2235-2239; Courouce', et al., La Gazette de la Transfusion (1999) N°155-Mars-Avril; Van Binsbergen, et al., J. Virol. Methods (1999) 82: 77-84), in addition to European implementation of nucleic acid testing. Serologic assays that combine antibody and antigen detection exhibit superior seroconversion sensitivity compared to assays that detect only antibody, because detection of antigen, which appears prior to antibody, reduces the seroconversion window. An early version of an HIV combo assay is described in Gallarda, et al., 1992, WO93/21346, Assay for Detection of HIV Antigen and Antibody.
Within several weeks after infection with HIV, individuals generally enter a clinical phase characterized by extensive viremia and acute symptoms. During this period, prior to seroconversion, HIV p24 core antigen can be detected transiently in serum or plasma specimens (antigenemia) (Devare, et al., (1990) In, Human Immunodeficiency Virus: Innovative Techniques. Monograph in Virology, J. L. Melnick (ed.), Basel, Karger, vol 18: 105-121; Kessler, et al. JAMA (1987 258: 1196-1199; Phair, J. P., JAMA (1987) 258: p1218; Allain, et al. The Lancet (1986) ii: 1233-1236; Kenny, et al., The Lancet (1987) 1(8532): 565-566; Wall, et al., The Lancet (1987) 1(8532): 566; Stute, R., The Lancet (1987) 1(8532): 566 Goudsmit, et al., The Lancet (1986) ii: 177-180; vonSydow, et al., Brit. Med. J. (1988) 296: 238-240; Bowen, et al., Ann. of Int. Med. (1988) 108: 46-48). After seroconversion, the core protein apparently is bound up by antibodies in circulating immune complexes, making core protein detection difficult and requiring immune complex disruption techniques (Schupbach, et al., AIDS (1996) 10:1085-1090; Kageyama, et al., J. Virol. Methods (1988) 22: 125-131; Mathiesen, et al., J. Virol. Methods (1988) 22: 143-148; Steindl, et al., J. Immunol. Methods (1998) 217: 143-151; Euler, et al., Clin. Exp. Immunol. (1985) 59: 267-275; Gupta, et al., New Eng. J. Med. (1984) 310: 1530-1531; Griffith, et al., J. Clin. Microbiol. (1995) 33: 1348-1350). After the initial viremic phase and throughout the remainder of the disease, the virus generally establishes a steady state level (reviewed in Coffin, J. M. Science (1995) 267: 483-489).
Core proteins from isolates of HIV-1 group O, HIV-1 group M, and HIV-2 are antigenically similar because they share regions of amino acid sequence homology. Human (or mouse) immune polyclonal sera (i.e., immunoglobulin) elicited against the core protein of one group or type will cross react against the core protein of a different group or type (Clavel, et al., Science (1986) 233; 343-346; Guyader, et al., Nature (1987) 326: 662-669; Barin, et al., Lancet (1985) 2: 1387-1389; Kanki, et al., Science (1986) 232: 238-243; Kanki, et al., Science (1987) 236: 827-831; Clavel, et al., Nature (1986) 324: 691-695; Hunt, et al., AIDS Res. Human Retroviruses (1997) 13: 995-1005; Gurtler, et al., J. Virol. Methods (1995) 51: 177-184; Mauclere, P. AIDS (1997) 11: 445-453). However, in contrast to human (or mouse) immune polyclonal sera, mouse or human monoclonal antibodies raised or elicited against the core protein of one HIV group or type may (Mehta, et al., U.S. Pat. No. 5,173,399; Butman, et al., U.S. Pat. No. 5,210,181; Butman, et al., U.S. Pat. No. 5,514,541) or may not (Mehta, et al., U.S. Pat. No. 5,173,399; Butman, et al., U.S. Pat. No. 5,210,181; Butman, et al., U.S. Pat. No. 5,514,541) react against the core protein of a different HIV group or type. Often, however, neither cross-reactivity nor shared reactivity (Tijssen, 1993 In, Laboratory Techniques in Biochemistry and Molecular Biology. R. H. Burdon and P. H. van Knippenberg, eds. Vol. 15. Elsevier, Amsterdam) of mouse monoclonal antibodies have been considered or taught (Kortright, et al., U.S. Pat. No. 4,888,290; Kortright, et al., U.S. Pat. No. 4,886,742). In cases where HIV-1 and HIV-2 core proteins were detected simultaneously (Butman, et al., U.S. Pat. No. 5,210,181; Butman, et al., U.S. Pat. No. 5,514,541), a combination of at least 3 monoclonals were required, and the resulting quantitative sensitivity against HIV-1 core protein was much greater (50-fold) than for HIV-2 core protein, indicating that the monoclonals identified cross-reactive epitopes and not shared epitopes. Typically, monoclonal antibodies display a lower affinity against cross-reactive antigens (epitopes) (Karush, F. (1978) In, Comprehensive Immunology, ed. R. A. Good, S. B. Day, 5: 85-116. New York/London: Plenum; Mariuzza, et al., Rev. Biophys. Biophys. Chem. (1987) 16: 139-159; Tijssen, (1993) In, Laboratory Techniques in Biochemistry and Molecular Biology. R. H. Burdon and P. H. van Knippenberg, eds. Vol. 15. Elsevier, Amsterdam) compared to the affinity against the immunizing antigen (epitope) or shared epitope, resulting in less sensitivity toward the cross-reactive antigen.
Shared epitopes are not readily identified, particularly within proteins of related but different sequence. A single amino acid change within an epitope can destroy or modify binding of a monoclonal antibody to that epitope (Mariuzza, et al., Rev. Biophys. Biophys. Chem. (1987) 16: 139-159). In addition, within proteins, amino acid changes (or differences) in sites outside of the epitope can change the epitope due to changes in protein folding (Mariuzza, et al., Rev. Biophys. Biophys. Chem. (1987) 16: 139-159; Laver, et al., Cell (1990) 61: 553-556), thus altering the binding of an antibody to the epitope. In this regard, the core proteins of HIV-1 Group M, HIV-1 Group O, and HIV-2 are related but not identical (Korber, ibid), and although it is known that cross-reactive epitopes exist between HIV core proteins, it is neither certain nor taught that shared epitopes are present.
The extensive genetic (and therefore antigenic) variability of HIV has not been predicted, although many scientific papers have sought to supply explanations for the mechanism(s) of variability (Meyerhans, et al., Cell (1989) 58: 901-910; Wain-Hobson, Curr. Top. Microbiol. Immunol. (1992) 176:181-193; Holland, et al., Curr. Top. Micorbiol. Immunol. (1992) 176: 1-20; Gao, F. et al., Nature (1999) 397: 436-441; Sharp, et al., Biol. Bull. (1999) 196: 338-342; Robertson, et al., Nature (1995) 374: 124-126; Zhu, J. Virol. (1995) 69: 1324-1327). Determination of HIV genetic (and therefore antigenic) variability has relied solely on many empirical observations that subsequently have led to phylogenetic classification based on variation of HIV nucleic and amino acid sequence (Korber, ibid). Similarly, prediction of shared epitopes between HIV (core) proteins cannot be made because (a) core protein sequences must first be discovered, (b) once discovered, genetic variation provides added complexity and uncertainty to the identification of shared epitopes and (c) epitope discovery and characterization are required to differentiate cross-reactive from shared epitopes. Shared epitopes between HIV-1 Group M, HIV-1 Group O, and HIV-2 could not be determined until the discovery of HIV-1 Group O in 1994 (Gurtler, et al., J. Virol. (1994) 68: 1581-1585; Haesevelde, et al., J. Virol. (1994) 68: 1586-1596; Charneau, et al., Virology (1994) 205: 247-253).
The role of monoclonal antibody affinity for equivalent quantitative detection of variable HIV core proteins generally has not been taught (Mehta, et al., U.S. Pat. No. 5,173,399; Gallarda, et al. WO93/21346; Zolla-Pazner, et al., U.S. Pat. No. 5,731,189; Mestan, et al., EP 0519866A1; Butman, et al., U.S. Pat. No. 5,210,181; Butman, et al., U.S. Pat. No. 5,514,541; Kortright, et al., U.S. Pat. No. 4,888,290; Kortright, et al., U.S. Pat. No. 4,886,742). An average affinity for a monoclonal antibody elicited against a protein antigen is 4.5×107 mol−1 (Mariuzza, et al., Rev. Biophys. Biophys. Chem. (1987) 16: 139-159; Karush, F. (1978) In, Comprehensive Immunology, ed. R. A. Good, S. B. Day, 5: 85-116. New York/London: Plenum). Additionally, immunization strategies to increase the probability of obtaining monoclonals against shared epitopes have not been taught.
Only by combining two unpredictable features of monoclonal antibodies, affinity and shared reactivity, can one reasonably expect to obtain monoclonal antibodies which can be used to detect equivalent amounts of related but non identical HIV core proteins. Simple cross-reactivity of monoclonal antibodies is likely to be insufficient to achieve equivalent quantitative detection of HIV core proteins. Rather, shared reactivity in combination with high affinity is required to achieve the desired result. The affinity of a monoclonal for a related core protein may be substantially lower than that determined with the immunizing core protein. In that case, the epitope is most likely cross-reactive and the affinity of the antibody for the cross-reactive epitope may severely limit the utility of the antibody for detection of diagnostically relevant (i.e., 25 pg p24/ml serum or plasma, Courouc•, et al., La Gazette de la Transfusion (1999) N° 155-Mars-Avril) concentrations of the cross reactive core protein.
There are currently no known descriptions of immunoassays using only 2 monoclonal antibodies to achieve equivalent quantitative detection of HIV-1 Group M, HIV-1 Group O, and HIV-2 core proteins. Thus, such an immunoassay is certainly desirable. Two or more monoclonals in combination with polyclonal sera (immunoglobulin) have provided the basis for immunoassays to detect HIV-1 core protein or simultaneously HIV-1 and HIV-2 core proteins (Mehta, et al., U.S. Pat. No. 5,173,399; Butman, et al., U.S. Pat. No. 5,210,181; Butman, et al., U.S. Pat. No. 5,514,541; Kortright, et al., U.S. Pat. No. 4,888,290; Kortright, et al., U.S. Pat. No. 4,886,742; Gallarda, et al. WO93/21346). Thus, in view of the above, previous literature fails to (a) describe or teach immunoassay restricted to two monoclonals for equivalent quantitative detection of HIV-1 Group M and HIV-2 core proteins, (b) describe or teach immunoassays restricted to two monoclonal antibodies for equivalent quantitative detections of HIV-1 group M, HIV-1 group O, and HIV-2 core proteins, (c) teach methods to overcome monoclonal affinity barriers recognizing cross-reactive antigens leading to non-equivalent detection of HIV-1 group M, O, and HIV core proteins, and (d) high affinity monoclonal antibodies against shared-epitopes as the methods and means to detect diagnostically relevant and equivalent amounts of non-identical core proteins from HIV-1 group M, HIV-2 group O, and HIV-2.
All U.S. patents, patent applications and publications referred to herein are hereby incorporated in their entirety by reference. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field
This invention is in the field of shipping (and display) containers for food and other lightweight items, particularly for relatively inexpensive bags of frangible foods such as Tostitos®, potato chips and the like, wherein container weight must be minimized for many reasons including shipping and handling cost while providing protection against breakage and crushing of the items during transportation, diaplay and handling, e.g., by forklift trucks.
2. Prior Art
Heretofore the shipping and display containers for such food items having utilized fairly heavy materials, including wood sections, an unwieldly number of parts and excessive assembly time and effort, and further have not been entirely satisfactory from the standpoint of container strength, cost of container manufacture, customer appeal, free standing stability, ease of handling, special dimensional adaptation for enhanced transport efficiency, environmental considerations such as container reuseability, container construction material recycleability, or the like, and in particular, where corrugated board is used for the construction, the prior containers have failed to provide adequate resistance to deformation in general, and particularly to twisting deformation of the containers caused, for example, by jostling of the loaded containers by forklift trucks and the like. | {
"pile_set_name": "USPTO Backgrounds"
} |
Media ratings and other audience metering information are typically generated by collecting media exposure information from a group of statistically selected households. Each of the statistically selected households, also called metered households, typically has a data logging and processing unit commonly referred to as a “home unit,” “meter” or “audience measurement device.” In metered households or, more generally, metering sites having multiple media presentation devices, the data logging and processing functionality may be distributed among a single home unit and multiple site units, where one site unit may be provided for each media presentation device or media presentation area and provides data to the home unit for processing and/or communicating to a central processing site. The home unit (or the combination of the home unit and the site units) includes sensors to gather data from the monitored media presentation devices (e.g., audio-video (AV) devices) at the selected site. | {
"pile_set_name": "USPTO Backgrounds"
} |
Wireless accessories for computers and other portable information appliances have been available for many years. For example, wireless keyboards, wireless mice, wireless printers and wireless modems may be operatively coupled to a computing device through an infrared (IRDA) communication link or other suitable wireless communication link. In addition, wireless radio frequency standards are being developed, such as Bluetooth (see e.g., www.bluetooth.com), IEEE 802.15.1, IEEE 802.11b or other suitable RF standards for local area network devices. However, the display devices associated with such devices typically still use a wired cable connection to the device. This is due in part to the large amounts of data, such as video pixel data, that must be passed from a frame buffer containing a rendered image, to the display device which may be an LCD panel, other digital panel or high resolution display device. LCD projectors and wall displays also typically have a cable interconnection between the source of the image information and the display device.
In addition, it is known to use image renderers, such as graphics accelerator chips, containing, for example, two dimensional and three dimensional rendering engines that interface with a main processor, such as a host CPU, to generate and present graphics and video information, in the form of overlays, and other video graphics images. However, systems that employ image rendering devices typically have hard wired connections between the image renderer, such as a graphics accelerator chip or host CPU, and a display device, such as an LCD.
In display systems that employ multiple graphics accelerators to, for example, speed up the generation of a rendered image for video games and other multimedia applications, each graphics accelerator generates a different part of the same image or a completely different image. As such, with dual graphics processor based systems, the operating system typically has to know that the two graphics accelerators exist, and the software drivers associated with the graphics accelerators have to know that another software driver associated with the other graphics accelerator exists so that they may be used to draw other portions of the same image. In addition, each of the two graphics accelerator chips typically cannot use the same memory space and avoid system resource conflicts. Accordingly, operating systems are typically modified to accommodate parallel graphics accelerator operation. Operating systems typically send drawing requests to two different software drivers associated with the two graphics accelerators alternate between line or image frame rendering. Moreover, such systems are not known that employ anything other than a wired connection to a monitor device. Accordingly, such systems may require special operating systems and can be cumbersome to use since they require additional cabling.
Other network-based systems are known that may have, for example, a console that sends drawings commands over a wired network connection to a network display terminal. Such systems may, for example, send different drawing commands to different network display terminals based on which user is associated with a given network display terminal. A special operating system is used to control different commands to the different network display terminals. Accordingly, such systems can require cabling requirements as well as special operating system control.
Accordingly, a need exists for a wireless display device and method that allows the removal of a wired display connection to allow additional flexibility in displaying images without requiring modification to the operating system or applications. | {
"pile_set_name": "USPTO Backgrounds"
} |
Ferroelectric memory arrays are generally well known in the data processing arts and include a plurality of word line rows and a plurality of bit line columns. The rows of word lines normally each include a plurality of metal-oxidesilicon (MOS) access transistors at the juncture of each word line and bit line. In one known type of ferroelectric memory circuit, a ferroelectric capacitor is connected between each access transistor and a plate line, and a sense amplifier is connected to receive two complementary input signals (BIT and BIT) from adjacent bit lines extending from a single cell consisting of two access transistors and two ferroelectric capacitors. When appropriate switching voltages are applied to the gates of the access transistors and to the plate lines common to one word line row, the access transistors in this word line are turned on so that the sense amplifier can then read the binary state of the accessed cells. The BIT and BIT signals are then amplified in the sense amplifier, and the sense amplifier determines the voltage and polarity on each adjacent ferroelectric capacitor within a cell. One such circuit is disclosed, for example, in U.S. Pat. No. 4,873,664 issued to Eaton and is incorporated herein by reference.
One disadvantage of the above approach in Eaton is that each cell requires at least two access transistors and two ferroelectric capacitors to generate the required BIT and BIT complementary inputs into the sense amplifier for determining the logical state of the memory cell. This is because the ferroelectric capacitors must be polarized in opposite states to provide a voltage difference on the BIT and BIT inputs to the sense amplifier. The two different memory states are associated with the two different polarities of this voltage difference. Since the charge on each ferroelectric capacitor varies significantly with temperature, capacitor area and ferroelectric film properties, this means that the charge-dependent sense voltage for each ferroelectric capacitor also varies, so that a fixed reference voltage cannot be used with each cell. That is, if one attempted to use a fixed reference voltage for a single transistor-single ferroelectric capacitor cell, the voltage differential between the fixed reference voltage and a logical "1" and a logical "0" on the ferroelectric capacitor would not be sufficiently large under all conditions of operation, e.g. temperature variations, to be detected by the sense amplifier. Normally, this voltage differential must be about 100 millivolts.
Thus, the prior art approach of Eaton requires twice as many transistors and twice as many capacitors and twice as much chip area as compared to a single transistor-single capacitor cell design, and it is the elimination of these latter requirements to which the reference circuit of the present invention is directed. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to techniques for determining signal characteristics, and more particularly to a method for automatically identifying the carrier frequency of a pulsed signal using a spectrum analyzer for accurately counting the frequency of selected signals.
In the analysis and design of electronic devices it is important to determine the characteristics of various electrical signals which exist within the electronic devices. The two principal instruments which have been developed for this purpose are the oscilloscope, which displays the signal in terms of amplitude and time, and the spectrum analyzer, which displays the signal in terms of amplitude and frequency. By observing the displayed signals produced by these instruments the characteristics of the signals may be determined by a skilled operator. With the advent of microprocessor controlled instruments the goal is to make these instruments more "user friendly", i.e., make the instruments so easy to use that measurements can be made with little operator interaction or experience.
On a spectrum analyzer signals are displayed as a plurality of frequency components, each component having an amplitude corresponding to the strength of that component. Therefore, for pulse signals there is displayed a main lobe centered about a carrier frequency. This main lobe contains a plurality of spectral lines separated by the pulse repetition frequency of the pulsed signal. A plurality of side lobes representing the harmonic frequencies of the main lobe exist on either side of the main lobe separated by 1/PW, where PW is the pulse width of the pulsed signal. The frequency spectrum may become so complex that it is not easy to determine precisely by observation of the main lobe which spectral line represents the carrier frequency for the pulsed signal.
What is desired is a method for automatically identifying the carrier frequency of a pulsed signal with minimal operator interaction. | {
"pile_set_name": "USPTO Backgrounds"
} |
This application relates generally to electrochemiluminescent reactions, and more particularly to detecting the presence of an analyte of interest, and if desired quantitating the amount present, by measurement of electromagnetic radiation emitted by the system being, investigated.
In Noffsinger, J. B. et al., Anal. Chem. 1987, 59, 865, experiments relating to chemiluminescence obtained utilizing a reaction sequence involving amines and a ruthenium-containing luminophore (Ru(bpy)33+) (xe2x80x9cbpyxe2x80x9d shall in all instances herein stand for xe2x80x9cbipyridylxe2x80x9d) were disclosed. See, also, Lytle, F. E. et al., Photochem. Photobiol. 1971, 13, 123. In this work, luminescence is achieved solely through chemical reactions, without triggering by electrochemical energy. While chemiluminescent techniques can be useful, electrochemiluminescent (xe2x80x9cECLxe2x80x9d) operations are preferable in several respects, for example: (1) there is greater control over the reaction sequence since the motive electrochemical energy can be interrupted with concomitant interruption of the reaction, whereas in chemiluminescent systems, the reaction sequence, once initiated, does not stop until completion; (2) luminophores can participate in multiple emissions whereas in chemiluminescent systems the luminophore only emits light once; (3) the apparatus employed is different from, and easier to work with than, that used in chemiluminescent techniques. However, successful generation of chemiluminescence with a particular system does not mean that the reaction system can be made to electrochemiluminesce, and thus the disclosure of Noffsinger et al. cannot fairly be extrapolated to predict similar results in an electrochemically stimulated system.
Early ECL reactions involved the annihilation of oppositely charged radical ions, produced by sequential oxidation and reduction at an electrode using a double potential step, for example, as described in Faulkner, L. R., et al., Electroanalytical Chemistry, A. J. Bard (Ed.), Vol. 10, Marcel Dekker, N. Y., 1977, Ch. 1; Tokel-Takvoryan, N. E., et al., Chem. Phys. Lett., 1974, 25, 235; Velasco, J. C., et al., Inorg. Chem. 1983, 22, 822; Luong, J. C., et al., J. Am. Chem. Soc. 1978, 100, 5790; Abruna, H. D., J. Electrochem. Soc. 1985, 132, 842; and Abruna, H. D., J. Electroanal. Chem. 1984, 175, 321. Upon homogeneous electron transfer between the sufficiently energetic and oppositely charged radicals, an excited state of one of the precursors can be formed, and subsequent emission by the species in the excited state occurs. Additionally, so-called energy deficient mechanisms involving triplet-triplet annihilations have been reported. See Freed, D. et al., J. Am. Chem. Soc. 1971, 93, 2097; Wallace, W. L. et al., J. Electrochem. Soc. 1978, 125, 1430.
In certain other ECL reactions, a luminophore has been used with an organic acid, such as an oxalate or pyruvate, to achieve electrogenerated chemiluminescence. Oxidative-reduction mechanisms, such as this, involve oxidation of Ru(bpy)32+ (herein, xe2x80x9cbpyxe2x80x9d stands for xe2x80x9cbipyridylxe2x80x9d) and the organic acid. However, in certain situations systems of this nature are disadvantageous because the reaction leading to luminescence is conducted at a pH which is disadvantageously acidic. These systems are lacking in versatility, since their application to assaying of numerous biological interactions requires a departure from physiological solution conditions, such as pH, leading to a disruption of the immunochemistry of the assayed system. Illustratively, see Ege, D. et al., J. Anal. Chem. 1984, 56, 2413; Rubinstein, I. et al., J. Am. Chem. Soc. 1981, 103, 512; Chan, M. M. et al., J. Am. Chem. Soc. 1979, 99, 5399.
In certain articles by Pragst and co-workers, a fluorescent aromatic hydrocarbon, oxazole or oxadiazole has been subjected to electrochemical energy in the presence of imidazole or pyridine derivatives in order to achieve luminescence. See Ludvik, J. et al., J. Electroanal. Chem. 1986, 215, 179; Pragst, F. et al., J. Electroanal. Chem. 1986, 197, 245; Pragst, F. et al., J. Electroanal. Chem. 1981, 119, 301; and Pragst, F. et al., J. Electroanal. Chem. 1980, 112, 339. However, in each of these instances the luminophore was not a metal-containing substance, but rather was a non-metallic organic compound.
Provision of materials and methods for conducting ECL reactions utilizing metal-containing ECL moieties and amine reductants, to exploit the combined benefits of both while avoiding the disadvantages attendant upon the use of each in other systems, would be a significant technological advance.
It is an object of the present invention to provide materials and methods suitable for generating electrochemiluminescence.
It is another object of the present invention to provide materials and methods suitable for the conducting of ECL assays.
It is a further object of the present invention to provide methods and materials suitable for the detection of electrochemiluminescence, and thereby a wide variety of analytes of interest which may be present over a wide range of concentrations.
It is an additional object of the present invention to provide methods and materials which are suitable for conducting highly sensitive ECL assays for the detection and quantitation of very small concentrations of analytes of interest.
It is still another object of the present invention to provide materials and methods suitable for conducting precise, repeatable, highly sensitive ECL detection and/or quantitation of analytes present over a wide concentration range in aqueous environments, as well as organic environments.
It is yet another object of the present invention to provide materials and methods suitable for an ECL assay to detect and/or quantitate metal-containing ECL moiety.
It is still a further object of the present invention to provide methods and materials suitable for ECL detection and quantitation assays of an analyte of interest at a pH which does not disrupt the immunochemistry of an assayed system, and which are particularly suitable for detection and quantitation of an analyte of interest at a physiological pH.
These and other objects of the present invention will become even more readily apparent after consideration of the following description of the invention.
As will be seen from the discussion hereinafter, the present invention is a powerful tool which permits attainment of the objects set forth in the preceding section.
Thus, in one aspect the present invention is a composition suitable for use in an ECL assay, wherein electromagnetic radiation emitted by said composition is detected, which composition comprises
(a) a metal-containing ECL moiety capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the excited ECL moiety to conditions sufficient to induce said emission;
(b) an amine or amine moiety which when oxidized forms a strong reducing agent; and
(c) an electrolyte capable of functioning as a medium in which the ECL moiety and amine or amine moiety can be oxidized.
In another aspect, the invention relates to a reagent suitable for use in providing a composition for conducting an ECL assay wherein electromagnetic radiation is emitted by a composition comprising members selected from the group consisting of (i) a metal-containing ECL moiety capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the excited ECL moiety to conditions sufficient to induce said emission, (ii) an amine or an amine moiety which when oxidized forms a strong reducing agent, and (iii) an electrolyte capable of functioning as a medium in which said ECL moiety and said amine or amine moiety can be oxidized, said reagent comprising an amine or amine moiety and one of the other two members of said group.
In a further aspect, the present invention is directed to a kit for performing an ECL assay wherein electromagnetic radiation emitted by a composition is detected, which kit contains (i) a metal-containing ECL moiety capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the excited ECL moiety to conditions sufficient to induce said emission, (ii) an amine or an amine moiety which when oxidized forms a strong reducing agent, and (iii) an electrolyte capable of functioning as a medium in which said ECL moiety and said amine or amine moiety can be oxidized, said kit comprising at least one separate component in which one or more members of the croup consisting of said ECL moiety (i), amine or amine moiety (ii), and electrolyte (iii) is included.
In still another aspect, the present invention relates to a method of generating emission of electromagnetic radiation, which comprises the steps of
(a) forming a composition comprising (i) a metal-containing ECL moiety capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the excited ECL moiety to conditions sufficient to induce said emission; (ii) an amine or amine moiety which, when oxidized, forms a strong reducing agent; and (iii) an electrolyte capable of functioning as a medium in which said ECL moiety and said amine or amine moiety can be oxidized;
(b) exposing the composition under suitable conditions to an amount of electrochemical energy effective to induce the composition to emit electromagnetic radiation; and
(c) detecting emitted electromagnetic radiation.
In an additional aspect, the invention also is directed to a method of detecting or quantitating an analyte of interest by ECL assay, which comprises
(1) forming a composition comprising
(a) a sample to be tested for the analyte of interest,
(b) at least one substance selected from the group consisting of
(i) additional analyte of interest or an analog of the analyte of interest,
(ii) a binding partner of the analyte of interest or its said analog, and
(iii) a reactive component capable of binding with (i) or (ii),
(c) a metal-containing ECL moiety capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the excited ECL moiety to conditions sufficient to induce said emission, said ECL moiety being capable of entering into a binding interaction with the analyte of interest or a substance defined in (b)(i), (b)(ii), or (b)(iii);
(d) an amine or an amine moiety which, when oxidized, forms a strong reducing agent, and
(e) an electrolyte capable of functioning as a medium in which said ECL moiety and said species can be oxidized;
(2) exposing said composition to an amount of electrochemical energy effective to induce the composition to emit electromagnetic radiation; and
(3) detecting emitted electromagnetic radiation.
In yet another aspect, the present invention relates to a system for ECL detection or quantitation of an analyte of interest in a sample, said system comprising:
(a) a sample,
(b) at least one substance selected from the group consisting of
(i) added analyte of interest or an analog of the analyte of interest,
(ii) a binding partner of the analyte of interest or its said analog, and
(iii) a reactive component capable of binding with (i) or (ii),
xe2x80x83wherein one of said substances is linked, either directly or through one or more other molecules, to a metal-containing ECL moiety which is capable of being converted to an excited state from which electromagnetic radiation is emitted upon exposure of the ECL moiety to conditions sufficient to induce said emission
(c) an amine or amine moiety which is capable of being converted to a strong reducing agent and an electrolyte;
(d) means for inducing the ECL moiety to emit electromagnetic radiation; and
(e) means for measuring the emitted radiation to determine the presence or quantity of the analyte of interest in the sample.
The xe2x80x9cECL moietyxe2x80x9d or xe2x80x9cmetal-containing ECL moietyxe2x80x9d is sometimes referred to as a xe2x80x9clabelxe2x80x9d, xe2x80x9clabel compoundxe2x80x9d, xe2x80x9clabel substancexe2x80x9d, etc. It is within the scope of the invention for the species termed xe2x80x9cECL moietyxe2x80x9d, xe2x80x9cmetal-containing ECL moietyxe2x80x9d, xe2x80x9corganometallicxe2x80x9d, xe2x80x9cmetal chelatexe2x80x9d, xe2x80x9ctransition metal chelatexe2x80x9d and xe2x80x9crare earth metal chelatexe2x80x9dxe2x80x94when utilized in certain of the composition, reagent, kit, method, or system embodiments in accordance with the inventionxe2x80x94to be linked to other molecules such as an analyte or an analog thereof, a binding partner of the analyte or an analog thereof, a further binding partner of such aforementioned binding partner, or a reactive.component capable of binding with the analyte, an analog thereof or a binding partner as mentioned above. The above-mentioned species can also be linked to a combination of one or more binding partners and/or one or more reactive components. Additionally, the aforementioned species can also be linked to an analyte or its analog bound to a binding partner, a reactive component, or a combination of one or more binding partners and/or one or more reactive components. It is also within the scope of the invention for a plurality of the aforementioned species to be bound directly, or through other molecules as discussed above, to an analyte or its analog.
It is similarly within the scope of the invention for the aforementioned xe2x80x9ccompositionxe2x80x9d, hereinafter sometimes an xe2x80x9cECL compositionxe2x80x9d, or a xe2x80x9csystemxe2x80x9d to contain unstable, metastable and other intermediate species formed in the course of the ECL reaction, such as an ECL moiety in an excited state as aforesaid and the above-mentioned strong reducing agent.
Additionally, although the emission of visible light is an advantageous feature of certain embodiments of the invention it is within the scope of the invention for the composition (hereinafter sometimes xe2x80x9cECL compositionxe2x80x9d) or system to emit other types of electromagnetic radiation, such as infrared or ultraviolet light, X-rays, microwaves, etc. Use of the terms xe2x80x9celectrochemiluminescencexe2x80x9d, xe2x80x9celectrochemiluminescentxe2x80x9d, xe2x80x9celectrochemiluminescexe2x80x9d, xe2x80x9cluminescencexe2x80x9d, xe2x80x9cluminescentxe2x80x9d and xe2x80x9cluminescexe2x80x9d in connection with the present invention does not require that the emission be light, but admits of the emission""s being such other forms of electromagnetic radiation.
Substantial advantages are conferred on the practitioner of the present invention. The materials and methods in accordance with the invention provide an elegant technology for conducting the ECL detection and quantitation of an analyte of interest over a wide concentration range, down to a very small analyte concentration, in aqueous as well as organic environments. Good precision, and repeatability of detection and quantitation measurements are obtained. The utilization of metal-containing ECL moieties, especially metal chelates, in combination with amine-derived reductants, permits the practitioner of the invention to obtain advantages associated with use of each of these components, while avoiding disadvantages commonly encountered with other ECL techniques involving one or the other, but not both. Thus, the control over the reaction and the convenience of operation attendant upon using metal-containing species can be obtained without sacrifice of the capability of operation at a physiological pH. Conversely, the use of amine-derived reductants in the ECL interaction is advantageous: detection and quantitation functions can be performed without disrupting the immunochemistry of highly interesting biological systems which exist at physiological pH, but those functions do not involve use of organic luminophores that are incompatible with the aqueous environments of many of the highly interesting biological systems.
Furthermore, the present invention is useful in the detection and quantitation of numerous and highly varied analytes of interest as is discussed in the further description of the invention which follows.
Additionally, the versatility of the present invention is evident from the fact that it is not only useful in conducting heterogeneous assays, but also homogeneous assays. In this connection, heterogeneous assays are those in which ECL moiety linked directly or through one or more other molecules to the analyte of interest or its analog is separated, prior to exposure of such ECL moiety to electrochemical energy, from ECL moiety not linked to the analyte or its analog. Homogeneous assays, by way of contrast, are those in which there is no such separation before exposing the materials to electrochemical energy together. In the homogeneous assays of the present invention, electromagnetic radiation emitted when the ECL moiety is linked to the analyte or its analog differs from electromagnetic radiation emitted when the ECL moiety is not linked to the analyte or its analog. This can be achieved, for example, by sensing an increased or decreased emission amount corresponding to the presence of ECL moiety linked to analyte or its analog. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Technical Field
This disclosure relates to processors, and more particularly to translation lookaside buffer mechanisms within processors.
2. Description of the Related Art
Most processor designs that have paging mechanisms as part of the memory subsystem and include a translation lookaside buffer (TLB) to shorten the time required to do page translations and access memory. Although conventional TLB structures have been sufficient in providing physical address translations for a long time, in certain systems conventional TLB structures may not provide results fast enough. | {
"pile_set_name": "USPTO Backgrounds"
} |
With improvement of people's living standards, there are more and more concerns about the health. Currently, various fitness equipments have become available on the market, e.g., dumbbells, hand-muscle developers, treadmills, exercise bicycles and so on. Most people exercise just on such fitness equipment.
However, the “exercises” alone cannot deliver the best effect because the exercisers need an additional amount of oxygen during strenuous exercises. Particularly for those who suffer from some respiratory diseases, a supply of oxygen must be ensured.
Currently, however, most of the fitness equipments are not provided with an oxygen supplying device. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to integrated circuit structures. More particularly, this invention relates to a process for treating a film of low dielectric constant (k) dielectric material of an integrated circuit structure on a semiconductor substrate by implanting the film with hydrogen ions to inhibit subsequent cracking of the film of low k dielectric material and to further reduce the dielectric constant of the low k dielectric film.
2. Description of the Related Art
The shrinking of integrated circuits has resulted in levels of electrically conductive interconnects being placed closer together, as well as reduction of the horizontal spacing between the electrically conductive interconnects, such as metal lines, on any particular level of such interconnects. As a result, capacitance has increased between such conductive portions, resulting in loss of speed and increased cross-talk. One proposed approach to solving this problem of high capacitance is to replace the conventional silicon oxide (SiO2) dielectric material, having a dielectric constant (k) of about 4.0, with another insulation material having a lower dielectric constant to thereby lower the capacitance.
In an article by L. Peters, entitled xe2x80x9cPursuing the Perfect Low-K Dielectricxe2x80x9d, published in Semiconductor International, Volume 21, No. 10, September 1998, at pages 64-74, a number of alternate dielectric materials are disclosed and discussed. Included in these dielectric materials is a description of a low k dielectric material having a dielectric constant of about 3.0 formed using a Flowfill chemical vapor deposition (CVD) process developed by Trikon Technologies of Newport, Gwent, U. K. The process is said to react methyl silane (CH3xe2x80x94SiH3) with hydrogen peroxide (H2O2) to form monosilicic acid which condenses on a cool wafer and is converted into an amorphous methyl-doped silicone oxide which is annealed at 400xc2x0 C. to remove moisture. While the use of carbon-doped silicon oxide dielectric materials, as well as other materials mentioned in the Peters article, has resulted in a reduction in capacitance in integrated circuit structures utilizing such materials, a problem has been noted in the processing of such low k dielectric materials. After formation of a film of low k dielectric material, it is customary to subject the film to an anneal to drive off any moisture which may have formed during the process of making and depositing the low k film. The low k dielectric film has been noted to have a tendency to develop cracks during such exposure to elevated temperatures. Presumably the cracking results from stresses developed in the film during polymerization and structure formation which is accelerated by heating. The removal of water from the film during the heating step and resultant increase in film porosity may result in film shrinkage. The differences between the physical properties (thermal expansion coefficients, rigidity, etc.) of the low k film and the substrate may also contribute to the cracking problem.
In any event, the cracking of films of low k dielectric material during subsequent exposure to high temperatures, such as found in annealing processes (e.g., 400xc2x0 C. or higher), results in an unacceptable reduction in yield which must be addressed. It would, therefore, be desirable to provide a process for treating such films of low k dielectric material to inhibit cracking of such films upon exposure to annealing temperatures.
It has been proposed by others to treat the film of low k dielectric material in a hydrogen plasma to enhance the resistance to cracking. However, such plasma treatment has been found to be only superficial, affecting only the surface and a very shallow depth of the film. Apparently, normal plasma conditions are insufficient to affect the deeper levels or regions of the low k film of dielectric material. The computation of the penetration depth of the dopant peak Rp of H+ ions with the energy xcx9c500 eV (the average ion energy of hydrogen ions in a plasma generated in a diode mode) into amorphous silicon oxide (SiO2) film shows that the Rp is near 100 Angstroms (xc3x85). In reality, the dominant ions in a hydrogen plasma are H2+ ions, and the penetration depth of these ions into SiO2 will be even smaller. Therefore the bulk of low k dielectric films, which may range from 4000 xc3x85 to 8,000 xc3x85 in thickness, cannot be treated by a conventional hydrogen plasma.
Chu et al., in an article entitled xe2x80x9cA New Way To Make SOI Wafersxe2x80x9d, published in the May 1997 edition of Solid State Technology, describes the use of plasma immersion ion implantation (PIII) for implanting oxygen in the formation of SOI (silicon-on-insulator) wafers, and further describes the implantation of helium and hydrogen into the silicon wafer by PIII to form a plane of implanted ions in the wafer along which cracking of the wafer will occur.
A film of low k dielectric material formed on a semiconductor substrate is treated to inhibit subsequent cracking of the film of low k dielectric material, and to further reduce the dielectric constant of the low k dielectric material by implanting the film of low k dielectric material with hydrogen ions by applying a negative DC bias to the semiconductor substrate in the presence of a plasma in hydrogen-containing gases. The semiconductor substrate, with the film of low k dielectric material thereon, is mounted on an electrically conductive substrate support in a reactor and a negative DC bias is applied to the semiconductor substrate by connecting the electrically conductive substrate support to a source of negative DC bias while hydrogen ions are generated by the plasma in the reactor to thereby cause hydrogen ions to implant into the film of low k dielectric material on the semiconductor substrate to thereby inhibit cracking of the low k film of dielectric material, and to further reduce the dielectric constant of the film. | {
"pile_set_name": "USPTO Backgrounds"
} |
The destruction of polychlorinated biphenyls (PCBs) has been the subject of a great deal of speculation, controversy, and research. The presently acceptable method is high temperature incineration, followed by scrubbing the off-gas to remove hydrogen chloride. This is reported to be 99.99% efficient. This means that if one hundred tons are "destroyed" annually, that only twenty pounds will be allowed to escape to the atmosphere in the vicinity of the incinerator--a considerable quantity! Part of the material which thus escapes can be presumed to be dioxins, which are extremely toxic, and thus a greater hazard than an equivalent quantity of PCB.
Recent publications Chemical Week, Sept. 17, 1980, and Chemical and Engineering News, Sept. 22, 1980) have publicized a liquid method which is portable, and reclaims the transformer oils which are contaminated by the PCBs.
In addition to PCBs, there are many halogenated pesticides, chemical intermediates, and side products which are filling both legal and illegal dump sites and present serious hazards to the public health. There are also millions of tons of equipment, soils and sludges which are contaminated with these materials. This invention is applicable to destruction of these materials in a safe, inexpensive manner. | {
"pile_set_name": "USPTO Backgrounds"
} |
Field
The disclosure generally relates to fire-rated building structures. In particular, the disclosure relates to fire-rated joint systems, wall assemblies, and other building structures that incorporate the fire-rated joint systems.
Description of the Related Art
Fire-rated construction components and assemblies are commonly used in the construction industry. These components and assemblies are aimed at inhibiting or preventing fire, heat, and smoke from leaving one room or other portion of a building and entering another room or portion of a building. The fire, heat or smoke usually moves between rooms through vents, joints in walls, or other openings. The fire-rated components often incorporate fire-retardant materials which substantially block the path of the fire, heat or smoke for at least some period of time. Intumescent materials work well for this purpose, because they swell and char when exposed to flames helping to create a barrier to the fire, heat, and/or smoke.
One particular wall joint with a high potential for allowing fire, heat or smoke to pass from one room to another is the joint between the top of a wall and the ceiling, which can be referred to as a head-of-wall joint. In modern multi-story or multi-level buildings, the head-of-wall joint is often a dynamic joint in which relative movement between the ceiling and the wall is permitted. This relative movement is configured to accommodate deflection in the building due to loading of the ceiling or seismic forces. The conventional method for creating a fire-rated head-of-wall joint is to stuff a fire-resistant mineral wool material into the head-of-wall joint and then spray an elastomeric material over the joint to retain the mineral wool in place. This conventional construction of a fire-rated head-of-wall joint is time-consuming, expensive and has other disadvantages that are described herein.
A wall assembly commonly used in the construction industry includes a header track, bottom track, a plurality of wall studs and a plurality of wall board members, possibly among other components. A typical header track resembles a generally U-shaped (or some other similarly shaped) elongated channel capable of receiving or covering the ends of wall studs and holding the wall studs in place. The header track also permits the wall assembly to be coupled to an upper horizontal support structure, such as a ceiling or floor of a higher level floor of a multi-level building.
Header tracks generally have a web and at least one flange extending from the web. Typically, the header track includes a pair of flanges, which extend in the same direction from opposing edges of the web. The header track can be slotted header track, which includes a plurality of slots spaced along the length of the track and extending in a vertical direction. When the wall studs are placed into the slotted track, each of the plurality of slots accommodates a fastener used to connect the wall stud to the slotted track. The slots allow the wall studs to move generally orthogonally relative to the track. In those areas of the world where earthquakes are common, movement of the wall studs is important. If the wall studs are rigidly attached to the slotted track and not allowed to move freely in at least one direction, the stability of the wall and the building might be compromised. With the plurality of slots, the wall studs are free to move. Even in locations in which earthquakes are not common, movement between the studs and the header track can be desirable to accommodate movement of the building structure due to other loads, such as stationary or moving overhead loads, as described above.
Recently, improved methods of providing a fire-rated head-of-wall joint have been developed. One example of a fire-rated wall construction component is a head-of-wall fire block device sold by the Assignee of the present application under the trademark FireStik®. The FireStik® fire block product incorporates a metal profile with a layer of intumescent material on its inner surface. The metal profile of the FireStik® fire block product is independently and rigidly attached to a structure, such as the bottom of a floor or ceiling, at a position adjacent to the gap between the wallboard (e.g., drywall) and the ceiling on the opposite side (i.e., outside) of the wallboard relative to the studs and header track. The intumescent material, which is adhered to the inner surface of the metal profile, faces the wallboard, stud and header track. The space created in between the wallboard and ceiling, and the space between the stud and header track, allows for independent vertical movement of the stud in the header track when no fire is present.
When temperatures rise, the intumescent material on the FireStik® fire block product expands rapidly and chars. This expansion creates a barrier which fills the head-of-wall gap and inhibits or at least substantially prevents fire, heat and smoke from moving through the head-of-wall joint and entering an adjacent room for at least some period of time.
Still another example of an improved construction component for creating a fire-rated head-of-wall joint is a header track with integrated intumescent material strips sold by the Assignee of the present application under the trademark FAS Track®. In contrast to the FireStik® fire block product, the FAS Track® header track product incorporates the intumescent material directly on the header track so that the fire block material is installed during the framing process. Both the FireStik® and the FAS Track® fire block products are typically installed by the framing crew. The integration of the intumescent material into the FAS Track® header track product eliminates the need to install an additional fire block product after the wall board has been installed, which is typically done by a different crew than the framing crew. | {
"pile_set_name": "USPTO Backgrounds"
} |
Zippers are commonly used to fasten opposing fabric portions. One typical use for zippers is to close two separate fabric portions which form a pocket in a garment or accessory. An advantage of using a zipper to close a pocket is that when the zipper is closed, items stored in the pocket are less likely to be inadvertently removed from the pocket.
One disadvantage of using a zipper to close a pocket is that the zipper adds bulk to the garment or accessory. Each zipper includes two sets of interlocking teeth attached to a trim or flashing material. The flashing material is sewn to the garment or accessory, adding another layer of material to the garment or accessory. Added bulk may be undesirable in garments which the user wishes to conform closely to the body for improved aerodynamics and aesthetics. Additionally, added bulk may be undesirable in garments because it may increase the risk of chafing where the added bulk rubs against the body of the user during wear. Added bulk may also be undesirable in accessories for the same reasons.
Another disadvantage of using a zipper to close a pocket is that the zipper adds material and labor costs to the production of the garment or accessory. Each added zipper must be sewn precisely into the garment or accessory to function properly, which complicates construction of the garment or accessory. Accordingly, each added zipper proportionately increases material and labor costs to the garment or accessory.
In view of the foregoing, it would be advantageous to provide a zipper arrangement which provides the advantages of closing a pocket and also minimizes the bulk added to the garment or accessory and minimizes the additional labor and material costs of the garment or accessory. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates generally to an apparatus for aligning glass sheets in a production line and, particularly, to an apparatus for aligning sheets in a windshield bending operation.
The movement of glass sheets along a production line presents the problem of properly aligning the sheets at one or more work stations. One prior art aligning apparatus is disclosed in U.S. Pat. No. 3,638,564 in which a glass sheet is moved on a conveyor belt to an orientating station where a pair of edge engaging members and a pair of end engaging members orient the glass sheet longitudinally and laterally on the conveyor belt. Suction then is applied to hold the glass sheet in place while the conveyor belt moves the glass sheet to a work station where a predetermined pattern is applied by a silkscreen process. Each of the edge engaging members is hydraulically actuated and its relative position is manually adjustable by rotation of a threaded rod in a threaded sleeve to which a hydraulic cylinder is pivotly secured.
U.S. Pat. No. 3,701,643 and U.S. Pat. No. 3,992,182 both disclose aligning devices for positioning a moving glass sheet on a conveyor in a glass sheet production line. A pair of glass edge engagement members are located on opposite sides of the conveyor and move with the conveyor at the speed of the glass sheet. The engagement members are mounted on reciprocating carriages which move into and out of engagement with opposed edges of the glass sheets to align them.
U.S. Pat. No. 4,205,744 discloses a device for locating a windshield as it is being moved between two conveyor lines. A locating bar is manually adjustable on a threaded shaft to permit location of various lengths of windshields. A pair of locating pads are provided at the ends of the locating bar. A windshield is moved by a first conveyor into a holding structure which will rotate the windshield through 180.degree. and move it laterally to place it on the end of a second offset conveyor. During the lateral movement, one edge of the windshield comes into contact with one of the locating pads to position the windshield when it is placed on the second conveyor.
U.S. Pat. No. 4,367,107 discloses an apparatus for aligning a pair of bent glass sheets in an assembly station. The stacked glass sheets are moved into the assembly station and guide rollers engage the top and bottom edges and the end edges of the glass sheets. Both sheets are engaged by suction means and separated vertically while a flexible sheet layer is inserted between them. The glass sheets are reassembled to form a sandwich to be laminated.
U.S. Pat. No. 4,440,288 and U.S. Pat. No. 4,488,846 both disclose sensors for controlling the spacing of objects being moved between two conveyors. In the '288 patent, pans of dough are collected at a gate positioned at the end of a grouping conveyor being fed from an unloader conveyor. A pan sensor is moved along the grouping conveyor to determine when a moving pan is a predetermined distance from one or more stopped pans so that the speed of the conveyor can be reduced below a speed at which rising dough would fall when the moving pan strikes the stopped pan. The '846 patent discloses a device for controlling the movement of an auxiliary conveyor which is feeding glass sheets onto a main conveyor. The auxiliary conveyor is stopped until the distance between the last sheet on the main conveyor and the next sheet on the auxiliary conveyor is equal to a predetermined distance at which point the auxiliary conveyor is started to move the stopped glass sheet onto the main conveyor.
U.S. Pat. No. 4,493,412 discloses a device for positioning glass sheets on a conveyor platform prior to removal by a robot. A leading edge of the glass sheet engages fixed stop pins. Then a pair of transversely moveable tables advance to engage the opposed side edges of the article. Finally, adjustable pins are moved vertically and longitudinally into engagement with the trailing edge of the article to align the article in a precise position relative to a fixed reference point.
U.S. Pat. No. 4,458,628 discloses a turn table for supporting a glass panel and moving it relative to a robot glass panel is supplied to the turn table by a conveyor. The panel is located on the turn table by a plurality of positioning shoes hydraulically actuated in a vertical direction to engage the peripheral edges of the glass panel. The panel is then gripped with vacuum cups and the shoes are retracted before the turn table begins rotation.
In a laminated anti-laceration windshield production line, an outer curved sheet, an inner curved sheet and a curved cover plate are stacked with intervening plastic layers. These glass sheets must be properly oriented prior to the lamination process in order to provide proper edge alignment for accepting a vacuum ring. Since the glass sheets are curved, they are formed of decreasing length from the outer sheet to the inner cover plate such that the edges can be aligned. All of the prior art systems discussed above would have a problem properly aligning the three differently sized sheets. | {
"pile_set_name": "USPTO Backgrounds"
} |
Potential drug target validation involves determining whether a DNA, RNA or protein molecule is implicated in a disease process and is therefore a suitable target for development of new therapeutic drugs. Drug discovery, the process by which bioactive compounds are identified and characterized, is a critical step in the development of new treatments for human diseases. The landscape of drug discovery has changed dramatically due to the genomics revolution. DNA and protein sequences are yielding a host of new drug targets and an enormous amount of associated information.
The identification of genes and proteins involved in various disease states or key biological processes, such as inflammation and immune response, is a vital part of the drug design process. Many diseases and disorders could be treated or prevented by decreasing the expression of one or more genes involved in the molecular etiology of the condition if the appropriate molecular target could be identified and appropriate antagonists developed. For example, cancer, in which one or more cellular oncogenes become activated and result in the unchecked progression of cell cycle processes, could be treated by antagonizing appropriate cell cycle control genes. Furthermore many human genetic diseases, such as Huntington's disease, and certain prion conditions, which are influenced by both genetic and epigenetic factors, result from the inappropriate activity of a polypeptide as opposed to the complete loss of its function. Accordingly, antagonizing the aberrant function of such mutant genes would provide a means of treatment. Additionally, infectious diseases such as HIV have been successfully treated with molecular antagonists targeted to specific essential retroviral proteins such as HIV protease or reverse transcriptase. Drug therapy strategies for treating such diseases and disorders have frequently employed molecular antagonists which target the polypeptide product of the disease gene(s). However the discovery of relevant gene or protein targets is often difficult and time consuming.
One area of particular interest is the identification of host genes and proteins that are co-opted by viruses during the viral life cycle. The serious and incurable nature of many viral diseases, coupled with the high rate of mutations found in many viruses, makes the identification of antiviral agents a high priority for the improvement of world health. Genes and proteins involved in a viral life cycle are also appealing as a subject for investigation because such genes and proteins will typically have additional activities in the host cell and may play a role in other non-viral disease states.
Viral maturation involves the proteolytic processing of the Gag proteins and the activity of various host proteins. It is believed that cellular machineries for exo/endocytosis and for ubiquitin conjugation may be involved in the maturation. In particular, the assembly, budding and subsequent release of retroid viruses, RNA viruses and envelop viruses, such as various retroviruses, rhabdoviruses, lentiviruses, and filoviruses may involve the Gag polyprotein. After its synthesis, Gag is targeted to the plasma membrane where it induces budding of nascent virus particles.
The role of ubiquitin in virus assembly was suggested by Dunigan et al. (1988, Virology 165, 310, Meyers et al. 1991, Virology 180, 602), who observed that mature virus particles were enriched in unconjugated ubiquitin. More recently, it was shown that proteasome inhibitors suppress the release of HIV-1, HIV-2 and virus-like particles derived from SIV and RSV Gag. Also, inhibitors affect Gag processing and maturation into infectious particles (Schubert et al 2000, PNAS 97, 13057, Harty et al. 2000, PNAS 97, 13871, Strack et al. 2000, PNAS 97, 13063, Patnaik et al. 2000, PNAS 97, 13069).
It is well known in the art that ubiquitin-mediated proteolysis is the major pathway for the selective, controlled degradation of intracellular proteins in eukaryotic cells. Ubiquitin modification of a variety of protein targets within the cell appears to be important in a number of basic cellular functions such as regulation of gene expression, regulation of the cell-cycle, modification of cell surface receptors, biogenesis of ribosomes, and DNA repair. One major function of the ubiquitin-mediated system is to control the half-lives of cellular proteins. The half-life of different proteins can range from a few minutes to several days, and can vary considerably depending on the cell-type, nutritional and environmental conditions, as well as the stage of the cell-cycle.
Targeted proteins undergoing selective degradation, presumably through the actions of a ubiquitin-dependent proteosome, are covalently tagged with ubiquitin through the formation of an isopeptide bond between the C-terminal glycyl residue of ubiquitin and a specific lysyl residue in the substrate protein. This process is catalyzed by a ubiquitin-activating enzyme (E1) and a ubiquitin-conjugating enzyme (E2), and in some instances may also require auxiliary substrate recognition proteins (E3s). Following the linkage of the first ubiquitin chain, additional molecules of ubiquitin may be attached to lysine side chains of the previously conjugated moiety to form branched multi-ubiquitin chains.
The conjugation of ubiquitin to protein substrates is a multi-step process. In an initial ATP requiring step, a thioester is formed between the C-terminus of ubiquitin and an internal cysteine residue of an E1 enzyme. Activated ubiquitin may then be transferred to a specific cysteine on one of several E2 enzymes. Finally, these E2 enzymes donate ubiquitin to protein substrates, typically with the assistance of a C3 protein, also known as a ubiquitin enzyme. In certain instances, substrates are recognized directly by the ubiquitin-conjugated E2 enzyme.
It is also known that the ubiquitin system plays a role in a wide range of cellular processes including cell cycle progression, apoptosis, and turnover of many membrane receptors. In viral infections, the ubiquitin system is involved not only with assembly, budding and release, but also with repression of host proteins such as p53, which may lead to a viral-induced neoplasm. The HIV Vpu protein interacts with an E3 protein that regulates IκB degradation, and is thought to promote apoptosis of infected cells by indirectly inhibiting NF-κB activity (Bour et al. (2001) J Exp Med 194:1299-311; U.S. Pat. No. 5,932,425). The ubiquitin system regulates protein function by both mono-ubiquitinotin and poly-ubiquitinotin, and poly-ubiquitinotin is primarily associated with protein degradation.
The vesicular trafficking systems are the major pathways for the distribution of proteins among cell organelles, the plasma membrane and the extracellular medium. The vesicular trafficking systems may be directly or indirectly involved in a variety of disease states. The major vesicle trafficking systems in eukaryotic cells include those systems that are mediated by clathrin-coated vesicles and coatomer-coated vesicles. Clathrin-coated vesicles are generally involved in transport, such as in the case of receptor mediated endocytosis, between the plasma membrane and the early endosomes, as well as from the trans-Golgi network to endosomes. Coatomer-coated vesicles include coat protein I (COP-I) coated vesicles and COP-II coated vesicles, both of which tend to mediate transport of a variety of molecules between the ER and Golgi cisternae. In each case, a vesicle is formed by budding out from a portion of membrane that is coated with coat proteins, and the vesicle sheds its coat prior to fusing with the target membrane.
Clathrin coats assemble on the cytoplasmic face of a membrane, forming pits that ultimately pinch off to become vesicles. Clathrin itself is composed of two subunits, the clathrin heavy chain and the clathrin light chain, that form the clathrin triskelion. Clathrins associate with a host of other proteins, including the assembly protein, AP180, the adaptor complexes (AP1, AP2, AP3 and AP4), beta-arrestin, arrestin 3, auxilin, epsin, Eps15, v-SNAREs, amphiphysins, dynamin, synaptojanin and endophilin. The adaptor complexes promote clathrin cage formation, and help connect clathrin up to the membrane, membrane proteins, and many of the preceding components. AP1 associates with clathrin coated vesicles derived from the trans-Golgi network and contains γ, β1, μ1 and σ1 polypeptide chains. AP2 associates with endocytic clathrin coated vesicles and contains α, β2, μ2, and σ2 polypeptides. Interactions between the clathrin complex and other proteins are mediated by a variety of domains found in the complex proteins, such as SH3 (Src homology 3) domains, PH (pleckstrin homology) domains, EH domains and NPF domains. (Marsh et al. (1999) Science 285:215-20; Pearse et al. (2000) Curr Opin Struct Biol 10(2):220-8).
Coatomer-coated vesicle formation is initiated by recruitment of a small GTPase (eg. ARF or SAR) by its cognate guanine nucleotide excahnge factor (e.g. SEC12, GEA1, GEA2). The initial complex is recognized by a coat protein complex (COPI or COPII). The coat then grows across the membrane, and various cargo proteins become entrapped in the growing network. The membrane ultimately bulges and becomes a vesicle. The coat proteins stimulate the GTPase activity of the GTPase, and upon hydrolysis of the GTP, the coat proteins are released from the complex, uncoating the vesicle. Other proteins associated with coatomer coated vesicles include v-SNAREs, Rab GTPases and various receptors that help recruit the appropriate cargo proteins. (Springer et al. (1999) Cell 97:145-48).
It would be beneficial to identify proteins involved in one or more of these processs for use in, among other things, drug screening methods. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to an aircraft, in particular to an airplane, having at least one fuel cell, having at least one supply line which connects the fuel cell to a fuel supply, having at least one outlet line by means of which fuel supplied by the supply line and not consumed in the fuel cell is drained off and having means for the influencing of the fuel flow through the fuel cell.
The use of fuel cells in aeronautics is known. The fuel cells deliver electrical energy which can be utilized to drive different components of an aircraft. The advantage of the use of fuel cells is an efficiency which is improved with respect to conventional systems with reduced pollution and noise emissions. In fuel cells known from the art, the supply of the fuels to the fuel cell takes place by means of supply lines which are in connection with a corresponding fuel supply. In this process, flow regulators, generally so-called mass flow controllers, are located in the supply lines and ensure the desired fuel flow through the anode side and the cathode side of the fuel cell. The disadvantage of such flow regulators is a comparatively high proneness to defects and the technical regulation effort associated with their use. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to charge pump circuits, and more particularly relates to charge pump circuits capable of high voltage operation.
The charge pump is a type of DC-DC voltage converter circuit that uses capacitors to store and transfer energy, typically in order to generate a higher voltage than that supplied to the circuit. They are used in a variety of applications. They are commonly used, for example, to generate the higher voltages required for the writing and erasing operations of non-volatile memories such as flash memories. They are also used to achieve higher gate drive voltages (Vgs) on MOSFETs to obtain a lower resistance from drain-to-source while the device is on (Rdson) for a same size device. They are also used as a supply in low voltage applications. The foregoing list of applications is not exhaustive.
A charge pump is typically constructed in a series of stages that step up the voltage created by the charge stored in one stage to a higher voltage in the next. FIG. 1 is a circuit diagram of an exemplary prior art two-phase charge pump circuit 10. The circuit includes metal oxide semiconductor field effect transistors (xe2x80x9cMOSFETs,xe2x80x9d or, simply xe2x80x9cFETsxe2x80x9d) T1-T12, capacitors C1-C6, and an inverter, connected as shown. The circuit has three identical stages 14, 15, 16, each stage including four FETs (T1-T4, T5-T8 and T9-T12, respectively), and two capacitors (C1 and C2, C3 and C4 and C5 and C6, respectively), connected as shown. A high voltage VH is provided to the first stage 14, while a square wave clock signal CLK is provided to one side of all stages, and its inverse, generated by inverter 12, is provided to the other side of all stages, as shown.
Each stage operates in similar manner, with increasing voltage being provided successively at the output of each stage, in a manner well known in the art. Thus, in successive half cycles of CLK, FETs T1-T12 operate in complementary fashion to pump charge onto the plates of capacitors C1-C6, creating a voltage across the capacitors, and then to use that voltage, which is raised during the transfer cycle by the voltage of the clock signal, to elevate the voltage across a capacitor in a next stage that is on the same side of the circuit by that voltage, less the threshold voltage of a connecting FET. The last stage provides an output voltage VOUT.
However, as the voltage generated by each stage increases, the threshold voltages of the transferring FETs can increase, due to the well-known backgating effect. This causes a successively lower voltage increase from one stage to the next. In fact, the threshold voltage of a transferring FET can become the same as the voltages of the clock signals driving the pump, at which point no further boosting is possible. To avoid this, in the charge pump circuit 10 the backgate is tied to the source on each FET, as shown. Thus, Vsb=0. This requires isolation of the circuit.
In addition, there is a significant challenge in designing a charge pump that can work over a large voltage range. One reason for this is that the charge pump voltage is usually referenced to the supply in some way, and as the supply voltage increases so too does VOUT. However, the capacitors are typically diffusion capacitors, which have a specific voltage tolerance. When the clock signal switches from the supply voltage in its high phase to a low voltage in its low phase, the voltage tolerance of a capacitor can be exceeded, causing breakdown of the capacitor. Thus, in designing a high voltage charge pump that can work over a very wide supply range, one must solve the problem of how to clock it, but not exceed the voltage tolerance of the capacitors.
U.S. Pat. No. 6,157,242, which issued on Dec. 5, 2000, to Haruyasu Fukui, et al., and was assigned to Sharp Kabushiki Kaisha, proposes a charge pump circuit arrangement to allow operation at a wide range of power supply voltages. In their scheme, normal clock signals are provided to early stages of a charge pump, but in order to overcome the problem associated with increasing transferring FET threshold voltage, and thus allow a higher output voltage to be generated, a clock signal boost circuit is provided for boosting voltages of the clock signals of later stages. In order to address the problem of having the charge pump work over a very wide range and still stay within the tolerances of the capacitors, they propose having their clock boosting capable of being enabled and disabled. For lower supply voltages, clock boosting would be enabled, while for higher supply voltages clock boosting would be disabled, to protect the capacitors against breakdown. However, this proposed solution provides a limited output voltage.
Another prior art solution, shown in FIG. 2, utilizes a conventional ring oscillator 17, with transfer circuitry 17a providing the oscillator signal to high voltage level shifters 18 to raise both the high and low voltage levels of the clock signals CLK and {overscore (CLK)}, in order to provide a higher output voltage, and using high voltage components in the charge pump (not shown). In this solution, high voltage references VH1 and VH2 are referenced linearly to supply, and provided to the level shifters, as shown. For example, VH1 could be at supply voltage, Vsupply, such as 5 volts, and VH2 at some specified voltage below Vsupply, with both rising and falling with Vsupply, but holding the difference in their voltages to close tolerance. While this solution does not limit the output voltage, as in the arrangement disclosed in U.S. Pat. No. 6,157,242, it does require a relatively large integrated circuit area to implement, as it requires the additional area for the level shifters, and for high voltage components used in the design. In addition, the approach shown in FIG. 2 is limited in clocking frequency because of the high voltage level shifters 18. The FET devices in that circuit are, of necessity, large and have high intrinsic capacitance, and so do not switch rapidly.
In accordance with the present invention there is provided a high voltage integrated circuit operable in a system having a low voltage reference, a high voltage reference, and a ground, for providing an output voltage higher than the high voltage reference. The integrated circuit includes a high voltage ground reference circuit, operable to provide a high voltage ground reference node. Also included is an oscillator, operable to provide a clock signal, the oscillator being connected to the high voltage reference and to the high voltage ground reference node. An isolated charge pump circuit is provided, operable to generate the output voltage and isolated in the integrated circuit from other circuitry.
These and other features of the invention will be apparent to those skilled in the art from the following detailed description of the invention, taken together with the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
} |
In today's society of smartphones, small form factor personal computing devices, and social media, pictures are constantly being taken and electronically distributed among various computing devices. Oftentimes, pictures are taken of someone and posted, for example, to a social media website without the consent of that person. Digital rights management systems and policies have been developed in an effort to prevent misuse of such images and other digital files. Digital rights management systems may be applied to an existing digital file to dictate whether it may be, for example, distributed, copied, saved, or printed.
Additionally, smartphones, digital cameras, and other handheld electronic devices are becoming computationally robust. For example, cameras with multiple lenses (e.g., 3D cameras) are equipped with additional features and able to determine depth when capturing an image. Additionally, such small form factor personal computing devices may include hardware to implement a variety of communication protocols, technologies, and techniques. For example, such devices may be able to triangulate another device to determine its location. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a hypodermic syringe assembly, and more particularly concerns a hypodermic syringe suitable for prefilling including a needle shield assembly having cannula sealing features and features to help prevent accidental needle sticks.
2. Description of the Prior Art
Many injectable medications are packaged and distributed in the hypodermic syringe that will eventually be used to administer the medication to the patient. Prefilled syringes are available from pharmaceutical manufacturers, and syringes are frequently prefilled in hospital pharmacies. In both instances, the prefilled syringe is subject to a variety of environmental challenges during storage, shipping and/or handling before the medication is administered to the patient. Accordingly, the contents of the syringe must be sealed to preserve their sterility.
Articles such as hypodermic syringe tip caps are sometimes used to seal the distal tip of a prefilled hypodermic syringe. Syringes having a permanently attached needle cannula can be sealed with a resilient needle shield as taught in U.S. Pat. No. 3,865,236 to Rycroft. Rycroft teaches a needle shield of resilient rubber closed at one end and adapted to be positioned in surrounding relationship with respect to the needle so as to normally maintain the needle in a sealed atmosphere. The needle shield of Rycroft seals the cannula so that the prefilled medication is not in fluid communication with the environment.
Resilient rubber needle shields such as those taught by Rycroft are widely used and accepted. However, in recent years there has developed an increased concern regarding the transfer of disease and/or infection to syringe users and healthcare professionals who accidentally stick themselves with hypodermic needles while preparing, using or disposing of a hypodermic syringe products. Placing an excessive force on the tip of a syringe and needle assembly having a resilient rubber needle shield may cause the needle to penetrate the needle shield to expose the sharp injection point. Although reshielding is neither preferred nor recommended by many people, circumstances arise where it is necessary or convenient for the user to reshield the needle after injection. A resilient needle shield can present a potential problem if it is reshielded improperly so that the needle pierces the sidewall of the needle shield or the distal end of the needle shield and sticks the user. Syringe assemblies having rigid plastic needle shields avoid some of these problems but are generally not suitable for prefilled glass syringes because they do not have the ability to seal the needle cannula and because of their hardness and relative inelasticity may not effectively attach to the tip of a glass syringe barrel which in normal manufacturing has a much broader range of tolerances than a plastic syringe.
One way to retain the positive and desirable features of the resilient needle shield and to reduce the potential for accidental needle sticks is to provide a hard plastic protector or cover which can be installed over the needle assembly having a barrel with fixed needle cannula and a resilient needle shield in place such as an already prefilled hypodermic syringe assembly. U.S. Pat. No. 4,430,082 to Schwabacher teaches an inflexible hollow cylindrical sleeve which fits over an elastomeric protective needle cover. The cylindrical sleeve is provided with flexible gripping means which when depressed exerts pressure on the inner elastomeric protective cover thereby allowing the cover to be removed along with the protective cylindrical sleeve. Although the teachings of Schwabacher provide an improvement the device still has several shortcomings with respect to prevention of accidental needle stick. First, if the syringe is assembled by hand, there is still the potential of sticking during the assembly process before the rigid cover is applied. After the rigid cover is applied to the syringe assembly it can be removed leaving the needle covered only by the elastomeric protecting cover, effectively returning the device to its original state, before the rigid sleeve was installed, having all the shortcomings recited for syringe assemblies without rigid needle sleeves.
A similar device is taught by Ambrosio et al. in U.S. Pat. No. 4,317,446. Ambrosio et al. teach a plunger rod/protector which fits over a elastomeric needle sheath on a prefilled syringe having a fixed needle cannula. The plunger rod/protector of Ambrosio et al. does not engage the sheath and maintains its position on the syringe assembly by engaging the outer surface of the syringe barrel so that the plunger rod protector can be installed and removed from the distal end of the syringe without removing the elastomeric needle sheath. Ambrosio et al. has all of the disadvantages of Schwabacher in that the initial assembly may still be accomplished manually providing the opportunity for an accidental needle stick and the plunger rod protector may be removed leaving the needle covered only by the elastomeric needle sheath.
A further improvement is taught by Ambrose et al. in U.S. Pat. No. 4,636,201. Ambrose et al. teach a rigid sheath cover adapted to be placed over a rubber needle cover on a hypodermic syringe. The rigid sheath cover has a plurality of spaced cantilever like teeth projecting outwardly from the tubular body of the cover to form the open end. At least two of the teeth include a lip projecting inwardly toward the center of the opening formed by the teeth for ripping the needle cover after installation. Ambrose et al. still have an initial shortcoming in that the syringe having the rubber needle cover is already assembled. Manual assembly or use before installation of the rigid sheath cover provides all of the opportunity for accidental needle sticks as the original prior art syringe before rigid covers are installed. Also, because the rigid sheath is installed over the rubber needle cover there is an opportunity for the user to be stuck by the needle during the process of applying the rigid sheath to the needle assembly of Abrose et al. The rigid sheath cover of Ambrose et al. also provides an additional chance for accidental needle sticks because a needle can properly enter the open end of the rubber needle cover, at an angle, and pass through the cover and the space between the spaced teeth to stick the user. The only apparent advantage of Abrose et al. over the devices of Ambrosio et al. and Schwabacher is that after installation it appears that the rubber needle cover will remain within the rigid sheath. However, the spaced teeth of the Ambrose et al. sheath cover must be flexible enough to deform while passing over a soft rubber needle cover to the final assembled position. If the teeth are very rigid they may not flex enough to pass over the rubber needle cover or tear the cover in the process of assembly. Accordingly, the Ambrose et al. device must perform a balancing act between being flexible enough for proper installation yet strong enough to retain the rubber needle cover after assembly.
Shields for sealing the contents of a prefilled hypodermic syringe and protecting the needle from the environment have been addressed by the prior art. Improvements involving rigid covers and protectors which can be installed on a prefilled syringe having a resilient needle sheath have also been addressed by the prior art. However, there is still a need for a simple, straight forward, reliable, easily fabricated hypodermic syringe assembly having a needle shield assembly which retains the cannula sealing and cleanliness protecting features of the resilient needle sheath and incorporates a rigid shield to help prevent accidental needle sticks during all phases of the assembly and operation and disposal of the syringe. | {
"pile_set_name": "USPTO Backgrounds"
} |
Conventional voicemail systems receive, store and provide voicemail messages for subscribers of the voicemail service. A “subscriber” is typically a person that has a relationship with the provider of the voicemail service. For example, the voicemail service may be provided by the local telephone company through which the subscriber receives local telephone service.
A problem with conventional voicemail services occurs when a subscriber wishes to retrieve his/her messages. For example, when a subscriber wishes to retrieve his/her messages, the subscriber typically calls a telephone number associated with the voicemail service and retrieves each message in the order in which the messages were stored. Therefore, the subscriber must listen to at least a portion of each message to determine who has left the message. Such a retrieval system is time consuming when a large number of messages have been stored. | {
"pile_set_name": "USPTO Backgrounds"
} |
There is shown in FIG. 1 an example of a watthour meter 1 according to the prior art. Although such meters come in various styles, they are generally comprised of a meter body 32 which mates with a socket 29 which may be attached to a conventional meter box (not shown). The meter body 32 has a base portion 2 to which a cover 41 is attached using lugs 40, shown in FIG. 2. The cover encloses a metering element for sensing the power consumed in a load circuit. Traditionally, the metering element was a mechanical register having a number of dials for indicating the power consumed. More recently, electronic meters have been developed in which the metering element is an electronic register 34 which, using techniques well known in the art, electronically performs the watthour accumulating function of a traditional mechanical register, as well as other specialized function, such time of day use and peak demand.
As shown in FIG. 1, the socket 29 is connected to ground via conductor 33. In addition, the socket 29 has two openings 31 through which the incoming and outgoing conductors of a three phase load circuit (not shown) are fed. Each phase of the load circuit is connected to one of three pairs of jaws 30 formed in the socket 29. A additional jaw 30 is connected to the ground wire of the load circuit. The meter body 32 has three pairs of blades 3 extending from the outboard side 38 of the meter base 2, each of which connects with one of the jaws 30 in the socket 29. Referring to FIG. 2, in this example, blade pairs 3.sup.1, 3.sup.2, and 3.sup.3 are connected via the jaws 30 to the first, second and third phases of the load circuit. Blade 3.sup.4 is connected via a jaw 30 to the ground wire of the load circuit.
As shown in FIG. 1, a conductor 43 connects each blade 3 to the other blade in the pair so that the circuit is not interrupted, thereby allowing the current flowing in the load circuit to pass through the meter 1. A current transducer 35 and a voltage transducer 42 are provided for each of the blade pairs 3.sup.1, 3.sup.2 and 3.sup.3 shown in FIG. 2. The current and voltage transducers 35 and 42, respectively, are connected to the metering element and step down the current and voltage in the load circuit to values suitable for metering. As shown in FIG. 2, a vent 12 is formed in the meter base.
In order to protect the meter from transient surges in either the utility service or user circuits connected to the meter, surge protectors, sometimes referred to as "lightening arrestors," are conventionally provided. As shown in FIGS. 2-4, according to the prior art, a three phase meter such as that shown in FIG. 1 is provided with three surge protectors, one for each phase. Each surge protector is comprised of an electrode 6, conductor 5, resistive block 8, ground strap 7 and spark gap 14. The electrodes 6 are connected by conductors 5 to one of the voltage input blades 3 in each blade pair in this example. A post 9 protruding from the meter base 2 secures each electrode 6 to the inboard side 36--that is, the side enclosed by the cover 41--of the meter base. As shown in FIG. 4, each resistive block 8 is disposed in a hole 15 formed in the meter base. A dimple 13 formed in the end of the electrode 6 presses the electrode against the resistive block 8. A hole 10 extends from the bottom of hole 15 and a ground strap 7 lies over the hole 10. Posts 9 secure the ground straps 7 to the outboard side 38 of the meter base 2. The end 44 of the ground strap 7 extends from the outboard side 38 so that it is spring loaded against the socket 29 when the meter body 32 is attached thereto. A dimple 13 formed in the ground strap 7 forms a spark gap 14 between it and the resistive block 8.
A voltage potential is created across the spark gap 14. During normal operation this potential is too small to cause arcing. However, a transient surge in any phase will increase the voltage developed across the spark gap 14 of the surge protector connected to that phase. If the voltage potential becomes great enough, the air within the spark gap 14 will ionize, thereby creating an arc across the gap which diverts the surge to ground via the ground strap 7, socket 29 and conductor 33. Since ionization creates gases in the spark gap 14 which are highly conductive, the resistive block 8 is placed in series between the electrode 6 and ground strap 7 to prevent the arcing from causing excessive current to flow and to ensure that this current flow extinguishes at the zero crossing of that current.
Although the surge protector arrangement according to the prior art, as described above, works well for its intended purpose, it requires a large number of components for a three phase meter. Specifically, the resistive blocks 8 and ground straps 7 must be duplicated for each phase. Moreover, since the paint on the socket 29 must be manually scrapped away in the vicinity of the ground strap 7 to ensure good electrical contact, the labor required to install a meter employing prior art surge protectors is significantly increased. In addition, since the resistive block 8 is mounted on the inboard side 36 of the meter base 2, the meter cover 41 must be removed to replace the resistive block. This increases the labor associated with maintaining the meter.
Accordingly, it would be desirable to provide a surge protector arrangement for a multi-phase watthour meter which did not require the multiplicity of components necessary under the prior art approach and which allowed the resistive block to be replaced without removing the meter cover. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to cosmetics in general and more particularly to a product incorporating a cosmetic component supported in a fibrillated polymer matrix.
Cosmetics have been used since early times to beautify the skin and hair. The manufacture of cosmetics is a 20th century development under the influence of Hollywood in the 1920's coupled with the development of mass production and mass marketing techniques. As a consequence, cosmetics were offered to the public at cheap prices. As one can ascertain, the cosmetic industry today is huge and there are a tremendous number of products utilized.
While most cosmetics are relatively simple, they contain many ingredients which are employed to formulate the various cosmetic preparations. Essentially a cosmetic chemist uses a variety of materials which are often based on emulsified mixtures of oils, water or water soluble products, pigments, talcs and so on.
Manufacturing processes of cosmetics can normally be divided into three main lines, as lipsticks and related sticks, creams and lotions, and compressed powders, as for example cake makeup. This application relates to compressed powder type of cosmetics, but is applicable to other cosmetic products as well.
In the prior art compressed powders were also referred to as cake makeup and are widely employed because of their ease of application and stability and also because they adhere to the skin easily. The most well known is a compressed face powder which usually is made from a mixture of talc, kaolin, zinc oxide and precipitated chalk. It also includes lanolin derivatives, wax and pigment such as titanium and iron oxides. The liquid constituents, including a humectant and perfume are sprayed into the powder while it is in a ribbon mixer. The product is milled to make it homogeneous and left to stand to allow air that has been entrained to escape and then pressed by one or more stages employing pressures between 200-250 psi to form a cake.
Cake eye shadows contain about 60% talc and an emollient which is a skin softening agent which allows the cake to be transferred by pressing out. Approved pigments are also added as, for example, a black coloration being provided by carbon black. Eye shadows of a metallic luster use finely ground metal such as aluminum or natural or synthetic pearlized materials. The formulation of such cosmetic products comprises a great deal of material including fairly extensive labor processes as well as other time consuming operations.
It is indicated that the dispersion of pigments in cosmetics may require different materials as above indicated and many different steps in order to provide the final product. These steps usually take an extreme amount of time and are labor and capital intensive.
It is an object of the present invention to provide a simple and efficient cosmetic which essentially contains a cosmetic component as a pigment supported by a polymer matrix.
As one will ascertain from the prior art, certain polymers, such as, for example, Teflon, possess the somewhat unique property in that they are fibrillatable. The use of fibrillatable polymers is well known in the prior art. Such polymers have been employed to support various elements with which said polymers are relatively non-reactive and readily capable of being dispersed therewith. Fluorocarbon and polypropylene polymers have such suitable characteristics and are capable of being fibrillated. As will be further explained, the term fibrillation means that the molecular structures of such polymers, when exposed to pressure and/or heat, e.g., high shear or milling, are disrupted and produce fibrils or minute fibers. These fibers are minute particles which are developed, in situ, from the fibrillatable polymers during processing. As such the fibrils intermesh in matrix-like configurations, whereupon they can be used with other components to provide various products.
For examples of prior art techniques using fibrillatable polymers, reference is made to the following U.S. patents. See U.S. Pat. No. 4,332,698 issued on June 1, 1982 and entitled "Catalyst Sheet And Preparation" by P. Bernstein, et al. This patent shows techniques employing fibrillatable polymers. U.S. Pat. No. 4,358,396 issued on Nov. 9, 1982 and entitled "Particulate Catalyst And Preparation" to P. Bernstein, et al. shows additional techniques. See U.S. Pat. No. 4,396,693 issued on Aug. 2, 1983 and entitled "Production Of A Cell Electrode System" by P. Bernstein, et al. See U.S. Pat. No. 4,433,063 issued on Feb. 21, 1984 and entitled "Hydrogen Sorbent Composition" by P. Bernstein, et al.
As indicated, the above patents are some examples of the use of fibrillatable materials which operate in conjunction with various compositions.
In any event, it has been determined that the use of a fibrillatable polymer, in conjunction with a cosmetic pigment, produces a vastly improved cosmetic article or product which exhibits extremely desirable characteristics, such as enhanced water resistance, a smooth silky feeling when applied to the skin of the user, extreme sheen, nonabrasiveness and an overall superiority to prior art products as indicated hereinabove. | {
"pile_set_name": "USPTO Backgrounds"
} |
Trusses are common components for many construction framing projects. However, despite the ubiquitous nature of trusses, it is relatively rare that any single truss design is replicated to a large extent. As such, many trusses are custom built for a particular construction project. Due to the highly customized residential and commercial construction markets, a strain is placed on truss manufacturers, which may be particularly acute in the area of set up. For that reason, much of the automation associated with truss fabrication has been focused on automating set up functions for cutting and assembly.
Currently, pieces of lumber are cut to the precise length and properly angled end, sorted and stacked after sawing, and transported to a staging area where truss assembly is performed. When the production schedule requires, the cut and sorted pieces may be moved to the assembly area along with needed connectors, which may include plates with teeth that imbed at least partially into wood members of the truss at their ends or along their length to hold the members together during the assembly process. The pieces may then be laid into an assembly jig, which provides a form or guide for member placement and truss assembly. The connectors may be placed on both top and bottom faces of the lumber at the joints between adjacent pieces.
Due to the custom nature of truss fabrication, it is often necessary to readjust the jig for each different truss. Accordingly, mechanisms have been developed to increase efficiencies related to setting up a jig. For example, jigging tables using lasers to outline jig or lumber patterns or having slidable guide members for more rapid adjustment of the jig have improved the ability of fabricators to customize jigs. However, the placement of lumber in the jig is typically done manually. The installation of connectors is also typically done by hand.
While the top face of the lumber is readily accessible, the bottom face is not since it is typically in contact with a jigging table or other substrate upon which the jig is provided. Accordingly, placement of a top plate, which is a connector engaging a top face of various members forming a joint in the truss, may not be difficult. In fact, various mechanisms including outlining a form of a plate on the various members have been developed to increase efficiency in placement of plates or connectors for the top faces of the lumber in the truss. However, it is typically necessary for the lumber pieces or members forming a particular joint to be simultaneously lifted so that the bottom plate can be slid underneath and properly located. Moreover, the location of the bottom plate is often determined by feel or merely from the positioning of edges that may be visible from above.
U.S. Pat. No. 5,440,977 to Poutanen describes one mechanism aimed at improving truss assembly by affixing connector or nail plates to some truss members prior to transporting the members to an assembly station. However, the assembly of truss members in Poutanen is manual. Although the prior plating of the connector plates may speed the truss assembly process, errors associated with manual handling and placement of truss members may still be introduced.
Given that truss manufacturing is likely to remain a highly customized process and also given that mechanisms for automating truss manufacturing may have the capability of providing time and cost savings that may present market advantages to those employing automation techniques, it may be desirable to introduce a mechanism that may overcome at least some of the disadvantages described above, or further automate the truss assembly process. | {
"pile_set_name": "USPTO Backgrounds"
} |
Conventional light emitting semi-conductor (LES) devices (LESDs), including light emitting diodes (LEDs) and laser diodes, and packages containing LESDs have several drawbacks. High power LESDs generate a substantial amount of heat that must be managed. Thermal management deals with problems arising from heat dissipation and thermal stresses, which is currently a key factor in limiting the performances of light-emitting diodes.
In general, LES devices are commonly prone to damage caused by a buildup of heat generated from within the devices, as well as heat from sunlight in the case of outside lighting applications. Excessive heat buildup can cause deterioration of the materials used in the LES devices, such as encapsulants for the LESDs. When LESDs are attached to flexible-circuit laminates, which may also include other electrical components, the heat dissipation problems are greatly increased.
Additionally, conventional LES devices and packages tend to be thick, which limits their uses in low form factor applications. Consequently, there is a continuing need to improve the design of flexible LES devices and packages to improve their thermal dissipation properties, as well as to allow for their use in low form factors. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to systems and methods for determining the free fatty acid content in oils, particularly edible oils.
Crude edible oils, such as soybean oil, cottonseed oil, corn oil, fish oil and the like, frequently contain undesirable amounts of free fatty acids which affect their quality. Various techniques are employed to remove free fatty acids and other contaminants. In one technique commonly used, a base is added to the oil to neutralize excessive amounts of free fatty acids. The free fatty acid content for many edible oils should be less than 0.05% and preferably in the range of 0.02 to 0.03%.
A system capable of measuring the free fatty acid content of oils during the refining process is highly desirable for a closer process control which can result in high yields, tighter product specification and an increase in the effectiveness of a subsequent bleaching step. A system capable of continuously producing an output signal representative of the free fatty acid content on a continuous basis is particularly desirable because it can be conveniently incorporated into completely automated process controls.
Conventional detectors employing an electrode type sensor usually cannot be conveniently used to determine the concentration of a component in a non-aqueous medium without incorporating complex auxiliary circuitry or other equipment. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to the field of sealed connections of threaded tubular components used in particular for drilling or operating hydrocarbon wells. When drilling or operating, the connections are subjected to large compressive and tensile loads and they must be prevented from coming apart. The connections are subjected to axial tension or compression, internal or external fluid pressure, bending or twisting, which may be combined, and of an intensity which can fluctuate. The seal has to be guaranteed despite the loads and despite the harsh conditions of use on site. The threaded connections are susceptible of being made up and broken out several times without degrading their performance, especially by galling. After break-out, the tubular components can be reused under other service conditions.
Under tension, a phenomenon of jump-out may occur and propagate from one thread to another, with the risk of the connection coming apart. This phenomenon is facilitated by a high internal pressure.
The Applicant has observed that this phenomenon can also be favoured by a high external pressure. Application WO 01/29476 proposes a threaded connection with a tapered threading, the male and female threadings respectively comprising a single threaded zone with a central sealing surface disposed in a central zone of the threaded zone. An abutment is provided at the free end of the male element. Other sealing surfaces are provided in the vicinity of the abutment. That connection has been highly satisfactory for many years.
A need has now arisen for a leap in the performance of a connection, in particular under combined tension and external pressure after strong compression, as well as in terms of the efficiency of the connection. The efficiency is generally defined as being the ratio of the critical section of the connection over the section of a regular portion of a tube between the two ends of a component. The critical section of the connection is equal to the minimum of the critical section of the male element and the critical section of the female element. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a method and system that enables taking a precautionary action in a vehicle, such as providing a warning to a vehicle driver about a potentially difficult or hazardous driving condition on the road network.
Advanced driver assistance systems (“ADAS”), including active safety and fuel economy systems, have been developed to improve the comfort, efficiency, safety, and overall satisfaction of driving. Examples of these advanced driver assistance systems include adaptive headlight aiming, adaptive cruise control, lane departure warning and control, curve warning, speed limit notification, hazard warning, predictive cruise control, and adaptive shift control, as well as others. Some of these advanced driver assistance systems use a variety of sensor mechanisms in the vehicle to determine the current state of the vehicle and the current state of the roadway in front of the vehicle. These sensor mechanisms may include radar, infrared, ultrasonic and vision-oriented sensors, such as digital video cameras and lidar. Some advanced driver assistance systems also use digital map data. Digital map data can be used in advanced driver assistance systems to provide information about the road network, road geometry, road conditions and other items associated with the road and terrain around the vehicle. Digital map data is not affected by environmental conditions, such as fog, rain or snow. In addition, digital map data can provide useful information that cannot reliably be provided by cameras or radar, such as curvature, grade, bank, speed limits that are not indicated by signage, traffic and lane restrictions, etc. Further, digital map data can provide a predictive capability well beyond the range of other sensors or even beyond the driver's vision to determine the road ahead of the vehicle, around corners, over hills or beyond obstructions. Accordingly, digital map data can be a useful addition for some advanced driver assistance systems.
Although these kinds of systems provide useful features, there exists room for further improvements. For example, it would be useful to identify locations on the road network where a relatively high number of traffic accidents have occurred. However, statistics pertaining to accidents are maintained by various different administrative entities that use different formats, standards, reporting methods, reporting periods, etc. Accordingly, it is difficult to obtain consistent information about traffic accidents on roads in a large geographic region, such as the entire United States or Europe. Moreover, data indicating locations where a statistically large number of traffic accidents occur may not indicate the causes of the accidents or how accidents can be avoided.
Accordingly, it is an objective to provide a system that facilitates taking a precautionary action in a vehicle, such as providing as warning to a vehicle operator, when approaching a location of a blind intersection. | {
"pile_set_name": "USPTO Backgrounds"
} |
Production management (or “production planning”) applications are used to increase the efficient utilization of manufacturing capacity, parts, components and material resources, using historical production data and sales forecasts. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention:
The present invention relates to polymeric products and to aqueous dispersions of polymeric products. More particularly, this invention relates to polymeric products containing cationic salt groups and to their use in electrodeposition.
2. Brief Description of the Prior Art:
Polymerization of diene and vinyl monomers in the presence of aqueous dispersions of anionic polymers is well known in the art. For example, U.S. Pat. No. 4,055,527 to Jozwiak and Das discloses polymerization of dienes and mixtures of dienes and vinyl monomers in aqueous dispersions in the presence of partially neutralized maleinized oils. U.S. Pat. No. 4,151,143 to Blank discloses a two-stage polymerization process for the preparation of anionic acrylic polymer emulsions. The first stage involves the preparation of an acrylic polymer with COOH groups. The polymer is neutralized with a base and dispersed in water. The second stage involves polymerizing a mixture of vinyl monomers in the previously prepared dispersion.
U.S. Pat. No. 4,064,087 to Das is similar to U.S. Pat. No. 4,151,143 mentioned above with the exception that the COOH-containing acrylic polymer also contains pendent double bonds. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to a roadway equipped with a power-generating means to generate power by virtue of the movement of a motor vehicle over the roadway. More particularly, this invention relates to a roadway equipped with such a power-generating means which is responsive to and actuated by the weight of a motor vehicle as it passes over such roadway. More especially, this invention relates to the generation of power by virtue of the weight of a motor vehicle passing over a roadway whereby fluid housed in a fluid housing is caused to move and to effect generation of energy via a transmission mechanism.
2. Discussion of the Prior Art
Volumes could be written about the heavy emphasis on energy consumption and energy generation. In these days with the dramatic rise in the cost of oil, which so adversely effects the cost of generating electricity, alternate sources are being considered for the generation of energy. For instance, it is becoming increasingly popular to decrease energy consumption in the home by the use of solar panels disposed on or near the same, whereby to extract heat from the sun and by heat exchange to heat the hot water within the building. Other means involving heat pumps and the like have been developed as a savings towards fuel oil consumption.
Electrical utilities are considering non-petrolium sources of power for the generation of electricity. Thus, many utilities have reconverted their facilities so that the electricity can be generated by steam heated by the use of coal or by means of a nuclear reaction.
There has been an increasing emphasis upon extracting energy from various sources. It is known to utilize the power from an automobile or other moving vehicle to generate power, especially electricity. Thus, for instance, it is known to use the movement of a locomotive or the revolution of the axial of a train to generate electricity for internal use within the train. Similarly it is known to use the revolutions of a bicycle tire to generate electricity for a portable lamp attached to the bicycle. It is also known from U.S. Pat. No. 3,859,589, to generate electricity for houses and the like by disposing an automobile's driven wheel over a pair of fluted rollers adapted to receive the same. The rollers in turn are rotated in response to the rotation of the automobile's drive wheel which automobile is disposed in stationary position whereby alternating current or direct current is generated. A device of that type is also disclosed in U.S. Pat. No. 3,943,370, where means are provided to jack the vehicle up and to utilize the revolutions of the vehicle to engage a means in turn connected to a generator. See also U.S. Pat. No. 2,712,109.
It has also been proposed to generate electricity by the use of vehicles passing along a roadway, such being disclosed in British Pat. No. 1,332,202 and U.S. Pat. No. 1,916,873.
Heretofore, the extraction of energy from a moving vehicle along a roadway has generally been either to effect rotation of a rotatable member disposed in said roadway (U.S. Pat. No. 3,885,163), or to utilize the weight of such vehicle to displace a lever arm or the like, which in turn effects revolution of a rotatable member by engagement of ratchets mounted on the lever arm with correspondingly shaped receiving teeth on the rotatable member. (U.S. Pat. No. 1,916,873). Alternatively, means have been provided in the path of the moving vehicle which restrains forward movement of the vehicle, these means being disposed significantly above the roadway and being connected to remotely positioned transmissions means. This is not only unsightly, but dangerous and such means are readily damaged by the movement of vehicles at high speeds or in turn damage the vehicles. Such a means for power generation by the use of the rotation of a motor vehicle over such obstructing means is impractical and undesirable. Not only does it present a dangerous obstacle in the path of the moving vehicle, but when it is struck by the moving vehicle, the force transmitted through the moving vehicle is of such magnitude as to toss the occupants of the vehicle about and endanger their physical well-being.
The use of ratchets mounted on a shaft responsive to means generally co-planar with the roadway, is far superior to the disposition of an obstacle in the path of the vehicle, but such conversion of the weight of the moving vehicle to energy is inefficient and subject to ready breakdowns. Moreover, such installations requires many complicated and relatively undependable mechanical parts. Means must be provided to redispose the shaft to its initial position, all of which involves valuable time loss and inefficiency in the conversion of weight from the moving vehicle to energy.
For instance, in U.S. Pat. No. 3,916,873, such a mechanism is disclosed which requires three separate plate members in the roadway for engagement with a single tire of the automobile and up to five of such plates (FIG. 4). These plates must be returned to their original position by the use of springs. While such a mechanism might have been useful in connection with the light-weight vehicles of the early 1930s, such a mechanism is impractical considering the heavy vehicles on modern roadways.
It became further desirable to provide such a power-extracting means which did not depend upon revolution of rollers disposed on the roadway and which generated the power without the use of undependable mechanical linkages, springs and the like to reset the mechanism. It became further desirable to provide the roadway equipped with such a power-generating means where the power was generated in response to the weight of a moving vehicle over a generally planar member disposed co-planar with the roadway.
It became still further desirable to provide such a weight responsive power-generating means in the roadway which did not require for its power generation, the movement of ratcheted shafts disposed beneath the roadway. | {
"pile_set_name": "USPTO Backgrounds"
} |
Magnetic Random Access Memory (MRAM) is a non-volatile computer memory technology based on magnetoresistance. Unlike typical volatile Random Access Memory (RAM) technologies which store data as electric charge, data in MRAM is stored by magnetoresistive elements. Generally, the magnetoresistive elements are made from two magnetic layers, each of which holds a magnetization. The magnetization of one layer (the “pinned layer”) is fixed in its magnetic orientation, and the magnetization of the other layer (the “free layer”) can be changed by an external magnetic field generated by a programming current. Thus, the magnetic field of the programming current can cause the magnetic orientations of the two magnetic layers to be either parallel, giving a lower electrical resistance across the layers, or antiparallel, giving a higher electrical resistance across the layers. The switching of the magnetic orientation of the free layer and the resulting high or low resistance states across the magnetic layers controls the state of a typical MRAM cell.
A type of MRAM cell is a spin torque transfer (STT) cell. A conventional STT cell includes a magnetic tunnel junction (MTJ) that functions as a magnetoresistive data storing element with a pinned magnetic layer and a free magnetic layer, and an insulating layer between the pinned and the free magnetic layers. An example of an insulating layer is magnesium oxide (MgO). The STT cell is coupled between an access device and a data line. The MTJ can be viewed as a multi-state resistor due to different relative orientations (e.g., parallel and antiparallel) of the magnetic moments, which can change the magnitude of a current flowing (e.g., passing) through the cell. Magnetic fields caused by currents flowing through the MTJ can be used to switch a magnetic moment direction of the free magnetic layer of the MTJ, which can place the device in a high or low resistance state. The pinned layer polarizes the electron spin of the programming current, and torque is created as the spin-polarized current flows through the MTJ. The spin-polarized electron current interacts with the free layer by exerting a torque on the free layer. When the spin-polarized electron current flowing through the MTJ is greater than a critical switching current density (JC) for writing the cell, the torque exerted by the spin-polarized electron current is sufficient to switch the magnetization of the free layer and thus change the resistance state across the MTJ. A read process can then be used to determine the state of cell, using a read pulse that causes a current to flow through the MTJ that has a sufficiently small magnitude to not disturb the state of the MTJ.
STT technology has some advantageous characteristics compared to other MRAM technology. The STT cell does not need an external magnetic field to switch the free layer but rather uses the spin-polarized electron current to switch the free layer. Further, scalability is improved with STT technology as the programming current decreases with decreasing cell sizes. Additionally, STT technology can provide a larger ratio between high and low resistance states, which improves read operations.
In writing a STT cell, the amplitude of a programming signal, such as a current or voltage pulse (referred to herein as a write pulse), is selected to be high enough to reduce or minimize the bit error rate (BER). However, this write pulse may cause some over stress of the tunnel barrier between the free and pinned magnetic layers of the MTJ. The tunnel barrier may be a tunnel oxide such as magnesium oxide (MgO). This stress may be attributable to the array topology, or to process spreads that reflect variability in the manufacturing process that may affect the MTJ and/or the access device. This stress may reduce the endurance of the memory cell as the stress may cause writing and reading failures after fewer write cycles. | {
"pile_set_name": "USPTO Backgrounds"
} |
(a) Field of the Invention
The invention relates to a driving device and a display device including the same, and more particularly, to a driving device capable of controlling gamma independently for each of red (R), green (G), or blue (B) colors and a display device including the same.
(b) Description of the Related Art
A general display device includes a display panel assembly which includes a plurality of pixels including a switching element and display signal lines, a gray voltage generator generating reference gray voltage, and a data driver which generates a plurality of gray voltages using the reference gray voltage and applies gray voltage corresponding to an image signal among the generated gray voltage to a data line among the display signal lines as a data signal.
A general gray voltage generator generates a defined number of the reference gray voltages according to a gamma curve of a liquid crystal display. The reference gray voltages include a set having a positive value for a common voltage Vcom and a set having a negative value for the common voltage Vcom. The data driver divides the reference gray voltages to generate gray voltages for an entire gray and may select the data signal among the gray voltages.
In order to implement a color display, each pixel of the display device uniquely displays one of primary colors such as R, G, and B or alternately displays the primary colors with time. Since the pixel displaying each of R, G, and B has a different gamma characteristic, when the same reference gray voltage is used based on the same gamma curve, color sense for each gray may not be uniform or a desired color may not be represented.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art. | {
"pile_set_name": "USPTO Backgrounds"
} |
In recent years the greenhouse effect due to CO2 has been pointed out as one of causes of the global warming, and a countermeasure against it is urgently required internationally to protect global environment. CO2 sources range various fields of human activities, including burning of fossil fuels, and demands to suppress their CO2 emission from these sources are on constant increase. In association with this, people have energetically studied means and methods for suppressing emission of CO2 from power generation facilities such as power plants which use an enormous amount of fossil fuels. One of the methods includes bringing combustion exhaust gas of boilers into contact with an amine-based CO2-absorbing solution. This method allows removal and recovery of CO2 from the combustion exhaust gas. Another method includes storing recovered CO2, i.e., not returning the recovered CO2 to the atmosphere.
Various methods are known to remove and recover CO2 from combustion exhaust gas using the CO2-absorbing solution. One of the methods includes contacting the combustion exhaust gas with the CO2-absorbing solution in an absorption tower, heating an absorbing solution having absorbed CO2 in a regeneration tower, and releasing CO2, regenerating the absorbing solution, and circulating the regenerated absorbing solution to the absorption tower again to be reused (Patent document 1). Patent document 1: Japanese Patent Application Laid-Open No. H7-51537. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The invention relates to a method and process for generating useful power. More particularly, the invention provides a combined reheat gas turbine and steam turbine cycle wherein a reheat combustor accepts a heated and compressed gas produced by a conventional gas generator, adds fuel and delivers reheated gas to a power turbine for directly generating power, exhaust gas from the power turbine forming superheated steam to drive the steam turbine. Alternatively, the reheat combustor for reheating the gas generator exhaust gas incorporates heat exchange means for superheating steam therein prior to delivery of reheated gas to the power turbine and optionally for production of reheated turbine steam for return to the steam turbine to furnish additional power thereto.
2. Description of the Prior Art
Research and development is currently being directed toward many configurations of power systems involving gas turbines because of the growing awareness of impending world energy shortages. The present invention relates to the need to focus technical attention to the reheat cycle and with use of the apparatus and processes of the present invention, the reheat gas turbine cycle and combined gas reheat and steam reheat cycle can appreciably increase power plant thermal efficiency to approximately an over-all 50% efficiency level or higher.
The reheat gas turbine cycle itself is well-known and has received considerable attention over the years, particularly in Europe. A regenerator has been used to heat a compressor's discharge air to improve cycle efficiency, and intercooling has been suggested for the same purpose. It is known that reheating can increase power output by 35 to 40%, but without use of regeneration, over-all cycle efficiency is degraded.
Another example of a reheat gas turbine cycle presently employed is the afterburner of a jet engine for aircraft use, such as in military aircraft and in certain commercial supersonic planes. The jet reheat cycle has been developed to get reliable service in applications where augmented power output is required for a short or limited time. The greatly increased power output comes at the expense, however, of markedly increased fuel consumption, owing to which, commercial applications have gone to efficient high bypass ratio fan jets for subsonic flight. Technology developed therefrom has made available second generation high-ratio high-firing temperature gas generators for industrial applications.
Yet, despite the existence of known technology, combined cycle power plants, such as those which utilize the processes and apparatus of the present invention, have not been developed. Attention has not been given to reheat gas turbine combined steam turbine cycle power plants because it has been thought that the degradation in efficiency of the reheat cycle would not offer an advantage, and also that increased fuel consumption would result. However, as will be pointed out hereinafter, thought must be given to the existence of higher level heat available in the exhaust and the over-all entropy changes as well as the concept of extracting maximum work at the high working fluid temperature levels possible with the present invention to obtain highest efficiency. Another explanation of the failure of others to utilize a reheat cycle process is the feeling that greater complication and cost of controls, and additional burner, compatibility of nozzle area, start-up procedures, and the like, would offset any advantage is specific power output, particularly at a higher fuel consumption.
Yet another reason can be cited for the failure of others to point in the direction of present invention. Aircraft derived gas turbines offer an advantage is potential physical arrangement for the reheat cycle in that a reheat combustor can be readily added between the gas generator and the power turbine, whereas conventional industrial or heavy duty gas turbines are ordinarily single shaft units for power generation, such conventional units not readily leading themselves to addition of a reheat burner. Moreover, second generation aircraft gas turbines fire at elevated temperatures and utilize high compression ratios suitable for reheat cycles, while industrial units, because of a single shaft configuration, are limited to lower ratios.
With the appearance of an increasing number of high-temperature and high-pressure-ratio gas turbines which lend themselves to reheat cycles, use of such equipment according to the process and teachings of the present invention becomes technically feasible, affording a practical utility for the generation of useful power, such as electrical power. | {
"pile_set_name": "USPTO Backgrounds"
} |
Examples of known molding systems are (amongst others): (i) the HYPET (TRADEMARK) Molding System, (ii) the QUADLOC (TRADEMARK) Molding System, (iii) the HYLECTRIC (TRADEMARK) Molding System, and (iv) the HYMET (TRADEMARK) Molding System, all manufactured by Husky Injection Molding Systems (Location: Canada).
U.S. Pat. No. 4,522,778 (Inventor: BACIU et al.; Published: 1985-06-11) discloses a method and apparatus for production of parts made from a plastics material using an injection press in which a mold cavity is defined by a mold surface and a surface of a movable piston. Firstly, the plastics material is introduced into the mold cavity, and during injection the piston is kept stationary for a time to form a rough mold and then retracted to form a parison. Secondly, after injection has been completed the piston is advanced again, and maintained in position while cooling takes place. Thirdly, the mold is opened and the part is ejected from the mold cavity.
European Patent Number 244783 (Inventor: MAUS et al.; Published: 1987-11-11) discloses a method and apparatus for injection compression molding of thermoplastic parts. Enlarged mold cavities receive plasticized resin, and compression of the injected resin is provided by a toggle clamp assembly. Preferably, the toggle clamp assembly provides multiple-stage compression of the resin to first redistribute the resin and vent the cavities and, second, compress the resin to compensate for cooling-induced shrinkage thereof. In the multiple cavities, because all cavities are equally compressed simultaneously, control of the molding process and balancing of the mold are readily accomplished.
European Patent Number 369009 (Inventor: UEHARA et al.; Published: 1990-05-23) discloses a desired quantity of a molten thermoplastic resin injected into a mold cavity which has a greater capacity than a product volume and is set in advance to a higher temperature than the temperature at which the thermoplastic resin starts curing under a normal pressure. The thermoplastic resin thus injected is cooled inside the mold cavity and is pressed before it is cooled down to a temperature at which it starts curing under a normal pressure. Due to this pressing, the glass transition point of the thermoplastic resin is shifted to a higher temperature side and the thermoplastic resin cures during a small temperature drop. The thermoplastic resin is cooled in the pressed state until dynamic rigidity at normal temperature and normal pressure is obtained. The thermoplastic resin is further cooled to a withdrawing temperature and the pressure applied to the thermoplastic resin is controlled so that dynamic rigidity of the thermoplastic resin during this cooling process can be maintained at the normal temperature and normal pressure by offsetting the rise of dynamic rigidity of the thermoplastic resin to be caused by cooling.
European Patent Number 425060 (Inventor: KASAI et al.; Published: 1991-05-02) discloses a process for effecting injection molding of plastic resin products on an injection molding apparatus including a metal mold composed of a slidable mold element and a fixed mold element defining together a mold cavity, an actuator for sliding the slidable mold element, and an injection means with an injection nozzle permissible of adjusting the nozzle flow path section. The operation includes: (i) a first molding step of injecting a molten resin into the mold cavity which has been preset by the slidable mold element so as to include a post-compression margin to be compressed afterwards in a second molding step, to effect the injection under a reduced molding pressure, while causing a temperature elevation and, thus, a viscosity reduction of the molten resin, until the mold cavity has been filled up, and (ii) a second molding step of compressing the resin so charged in the mold cavity by operating the slidable mold element to compress the charged resin to compensate said post-compression margin, so as to allow an effective pressing force to be imposed onto the charged resin within the mold cavity also after the mold gate has been sealed.
European Patent Number 593308 (Inventor: HENDRY; Published: 1994-04-20) discloses a mold apparatus and method to form a solid injection molded plastic part. The mold portions of the mold apparatus are closed, charges of molten thermoplastic and pressurized gas are sequentially injected into a mold cavity, and the mold portions are sequentially separated and closed. The pressurized gas forces the hot plastic away from one mold half and against the other mold half, and separation of the mold portions ensures uniform distribution of the pressurized gas behind the hot plastic, which pressure is maintained during cooling.
Depending on the application, the plastic completely packs the cavity, fills but does not pack the cavity, and the mating faces can be abutted or maintained partially separated when the mold portions close. A gas seal is formed by the plastic to prevent gas in the mold cavity from reaching the finished exterior surface of the part during shrinkage of the plastic.
European Patent Number 597108 (Inventor: MORIKITA; Published: 1994-05-18) discloses a localized pressurizing type injection molding machine for applying various processes to moldings during an injection-molding cycle; the injection molding machine can apply various processes to the moldings after the injection molding process.
European Patent Number 944466 (Inventor: HEHL; Published: 1999-09-29) discloses a process for manufacturing injection moldings in an injection molding machine for processing plasticized masses, in which a regulated subsequent pressure is applied by the injection molding unit. At least in the areas of the molding away from the sprue, the subsequent pressure is generated by a regulated volume alteration of the mold cavity. The subsequent pressure can be distributed during the subsequent pressure phase even in the case of complex moldings.
European Patent Number 1343621 (Inventor: WEINMANN; Published: 2003-09-17) discloses controlled correction of possible quantitative errors in the production of optical data supports. The cavity of the mold is only partially filled prior to the stamping phase. It is the subsequent stamping that is used to complete the filling process by moving one mold half. In the first phase of stamping or compressing the melt, the pressure is detected in defined positions of the molds or at a defined point in time and any deviation from a predetermined set pressure value is corrected by the immediate introduction of a movement change in the stamping process. By acting on the pressure conditions in the mold cavity, it is possible to influence the backflow before the sprue is set, in terms of a set weight value of the finished data support.
PCT Patent Application Number WO/2007/039766 (Inventor: CLARKE; Published: 2007-04-12) discloses a mold for mounting between relatively movable platens of an injection molding press for injection impact compression molding of an article. The mold comprises a cavity plate formed with a depression, a core plate having a projecting core at least part of the outer surface of which is cylindrical, and a closure plate movable relative to the core plate and the cavity plate, and a surface in sealing contact with the cylindrical outer surface of the core. A locking mechanism is provided to lock the closure plate relative to the cavity plate while permitting the core plate to move relative to the cavity plate.
U.S. Pat. No. 7,293,981 (Inventor: NIEWELS; Published: 2007-11-13) discloses a method and apparatus for compressing melt and/or compensating for melt shrinkage in an injection mold. The apparatus includes a cavity mold portion adjacent a cavity plate, a core mold portion adjacent a core plate, a mold cavity formed between the mold portions, and at least one piezo-ceramic actuator disposed between either or both of the core plate and the core mold portion and the cavity plate and the cavity mold portion. A controller may be connected to the at least one piezo-ceramic actuator to activate it, thereby causing the mold cavity volume to decrease, compressing the melt.
United States Patent Application Number 2008/0026239 (Inventor: BALBONI; Published: 2008-01-31) discloses a preform that is formed by an upper neck which maintains unchanged its form in the final object and a hollow body, joined to the neck. The method foresees the insertion, within a matrix cavity, of a metered body of polymeric material whose mass is metered according to a reference value, and the subsequent pressure insertion of a punch within the matrix cavity until it closes the mold's molding chamber, the punch conferring the shape to the inner surface of the preform and the matrix having an inner surface which confers the shape to the outer surface of the preform. In the molding of the preform, the error of the mass of the metered body with respect to the reference value is distributed in the hollow body, which undergoes a subsequent hot deformation until it achieves the final shape. In the mold, the matrix comprises at least one deformable wall whose inner surface defines at least part of the inner surface of the matrix part intended to give form to the hollow body of the preform, said deformable wall having, at least in part, a relatively thin thickness which permits it to be elastically deformed under the pressure of the polymeric material in the final preform molding step, thereby varying the thickness of the hollow body. | {
"pile_set_name": "USPTO Backgrounds"
} |
Customers of analytic software tools use the software to analyse their datasets. Such customers may encounter performance related issues that are data dependent and which occur only when very large volumes of data are analysed. Customers are often not able to provide the dataset to the supplier of the analytic software to help in the investigation of issues, due to confidentiality concerns and/or due to the difficulty in transporting the quantity of the data. Without access to the customer's actual datasets, the suppliers of analytic software tools may find it difficult to reproduce or understand the problems being experienced by the customer.
Suppliers of analytic software tools may attempt to replicate the issues encountered by the customer by using other similar datasets or by trying to generate synthetic data which resembles the customer's data. Often the success of this approach depends on how accurately the synthetic data resembles the original data. One known strategy is to guide the generation process using a data mining model built by the customer on their dataset. The data mining model does not contain any of actual data, but does describe rules, patterns and/or conditions that the actual data has been found to obey generally. Such models are typically small in size, and can usually be considered by a customer to contain no confidential information, so therefore they can be passed to the analytic software supplier.
One such approach is described in a paper by Eno and Thompson based on C&RT decision trees, a type of data mining model, entitled “Generating Synthetic Data to Match Data Mining Patterns”, IEEE Internet Computing, June 2008, see http://csce.uark.edu/˜cwt/DOCS/2008-06—IEEE-Internet-Computing—Reverse-Data-Mining—Eno-Thompson.pdf. A straightforward application of these approaches relies on the software supplier's test environment having the capacity to store large volumes of data to match those of a typical customer system. Also, the supplier may need to perform testing on behalf of many customers at the same time, leading to a likely bottleneck on storage resource. | {
"pile_set_name": "USPTO Backgrounds"
} |
There are conventional buckles of this type where a male member in plate form has an elastic piece (engaging piece) of which the end makes contact with the inner surface of a front plate portion of a female member in flat cylindrical form in an elastically deformed state as the male member is inserted into the female member, and the front plate portion of the female member is provided with a hooking portion (engaging portion) for hooking the end portion of the elastic piece in such a manner that an operating piece that is provided in the female member can be pressed inward through operation, and thereby, the elastic piece is elastically deformed in such a direction that the hooked (engaged) state with the hooking portion is released (see for example Patent Document 1).
[Patent Document 1] Japanese Unexamined Patent Publication 2000-106 (page 6, FIG. 19) | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to optical imaging devices, preferably devices operating in the infrared band, that are not cooled. This kind of imaging device is more particularly intended for use in a video camera or a telescope to form an image outside the visible band. This kind of device is sometimes referred to as an infrared focal plane.
2. Description of the Prior Art
As with any sensor, one of the main qualities required of an optical imaging device is to be able to deliver a signal of sufficient amplitude compared to the inherent noise of the device. Referring more particularly to infrared imaging devices, the most serious form of noise is usually the inherent thermal noise of the device, caused by the ambient temperature to which the device is exposed. To illustrate the importance of this effect, note that the normal human temperature of 37° C. corresponds to an infrared wavelength of substantially 10 micrometers.
The solution most widely used for reducing this noise consists in cooling the imaging device to a temperature corresponding to a wavelength outside the spectral domain to be imaged.
The devices used to obtain such cooling are bulky and expensive. They also introduce serious limitations on the dimensions of the imaging device and/or the cryogenic device and in some cases have a prohibitive power consumption. The simplest solution, which consists in using cooling by expansion of a gas contained in a pressurized cylinder, although it simplifies the production of the cryogenic device, leads to a considerable consumption of gas and is in practice essentially reserved for single-use devices, such as imaging devices in missiles.
In the case of a video camera generating successive frames, dispensing with a cooling device by using an array of thermocouples or an array of bolometers in combination with a device for chopping the signal between two successive frames has been envisaged. This produces the wanted signal, or at least a signal that is less degraded, by subtracting the noise from the total signal. However, this method has the drawback of not providing a reference signal, which degrades the accuracy of the measurements as a function of the temperature of the device.
Also known in the art are bolometer devices that dispense with chopping of the signal. However, these devices have a temperature drift such that they cannot be used for radiometric measurements. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention generally relates to electric lamp assemblies, and more particularly, to electric lamp assemblies having an improved structure for supporting a shroud.
2. Description of Related Art
Metal halide arc discharge lamps are frequently employed in commercial usage because of their high luminous efficacy and long life. A typical metal halide arc discharge lamp includes a quartz or fused silica lamp capsule or arc tube that is hermetically sealed within a borosilicate glass bulb or outer envelope. The arc tube, itself hermetically sealed, has tungsten electrodes press sealed in opposite ends and has a bulb portion containing fill material including mercury, metal halide additives, and a rare gas to facilitate starting. In some cases, both in low and high wattage lamps, the outer envelope is filled with nitrogen or another inert gas at less than atmospheric pressure. In other cases, particularly in low wattage lamps, the outer envelope is evacuated.
It has been found desirable to provide metal halide arc discharge lamps with a shroud which comprises a generally cylindrical tube of light-transmissive material, such as quartz, that is able to withstand high operating temperatures. The arc tube and the shroud are coaxially mounted within the lamp outer envelope with the arc tube located within the shroud. The shroud improves the safety of the lamp by acting as a containment device in the event that the arc tube shatters. The shroud allows the lamp outer envelope to remain intact by dissipating the energy of a shattering arc tube. The presence of a shroud expands the market for metal halide lamps into open-type (absence of an expensive cover plate) lighting fixtures. The shroud can also be used for color correction of the discharge source. For such color correction, the shroud includes a wavelength selective reflector or absorber or phosphor, such as a multilayer titania-silica dichroic reflector.
Sodium is an important constituent in metal halide arc discharge lamps, usually in the form of sodium iodide. Sodium is used to improve the efficacy and color rendering properties. It has long been recognized that arc tubes containing sodium lose sodium during operation by movement or migration through the arc tube wall. The iodine originally present in a metal halide lamp as sodium iodide is freed by sodium loss, and the iodine combines with mercury in the arc tube to form mercury iodide. Mercury iodide leads to increased reignition voltages, thereby causing starting and lamp maintenance problems, and shortening lamp life.
There is evidence that most of the sodium loss is due to a negative charge on the arc tube walls caused by photoelectric emission from electrified side rods used to support the arc tube and shroud within the outer envelope. One solution to the problem has been various electrically insulated, isolated, or "floating" mounting supports attached or clipped to the outer surface of the shroud and the press seals of the arc tube in combination with a current return line for the outer end electrode of a fine molybdenum wire, known as a flying lead, spaced as far away from the arc tube as possible and hugging the curve in the outer bulb. For example see U.S. Pat. Nos. 5,270,608, 5,252,885, 5,136,204, 5,122,706, and 4,963,790 the disclosures of which are expressly incorporated herein in their entirety. While such lamp constructions provide an improvement, the elements located outside of the shroud limit the outer diameter of the shroud and thus constrain the physical size or wattage of the arc tube that can be used with a given outer envelope, the press seals of the arc tube must have tight manufacturing tolerances and are prone to damage during assembly, and the structures require a relatively high number of parts and welds. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates generally to software processing, and more particularly, to methods and systems for intelligently and automatically selecting and utilizing networked computer resources to collectively execute process-flow-based computing operations.
2. Description of the Related Art
In today's fast paced computing world, more and more businesses use the World Wide Web (Web) to provide web services to consumers all over the world. In a simple scenario, a web service provider advertises the service provider's web services by registering the service provider's data with a web registry. In turn, a consumer of the web services (i.e., a client), communicates with the web registry, requesting the web registry to provide the client with information about a service provider satisfying a specific criteria transmitted by the client. The web registry then processes the request so as to locate the service provider that satisfies the particular criteria requested by the client. The registry then provides the client with the Uniform Resource Locater (URL) of the located service provider. Thereafter, if the client finds web services provided by the service provider satisfaction, the client communicates with the selected service provider. This simple scenario, however, rarely occurs.
In reality, web services are offered over the web by multiple service providers registered with several web registries for use by numerous clients. To make matters more complicated, each service provider may be implemented using different technologies (e.g., a net compatible server), each web registry may be implemented using different types of web registry documents (e.g., web service description language (WSDL), and each client can be based on different types of technologies (e.g., Java™ application based client). Further complicating the problems is that each of the service providers, web registries, and clients, may be implemented on different platforms. Accordingly, interactions between each combination of web registry, service provider, and client are rather complex as it may involve communications being based on different technologies and operating systems.
Additionally, communication between the web registries, service providers, and clients are synchronized. For instance, a service provider must ensure that the registry is up and running prior to service provider publishing the service provider's services on the web registry. In a like manner, a client must ensure that the registry is up and running prior to communicating a request for a web service. A client must further be sure that the service provider is running prior to communicating a request to the service provider. Thus far, however, such synchronization requirements have not been addressed, causing premature termination of communications between service providers, registries, and clients. In such scenarios, interactions must be restarted and the web services be re-dispatched. Additionally, the failed service provider, registry, or client must be restarted manually, requiring human intervention.
As the web services are being widespreadly used, to avoid such scenarios, the interactions between different service providers, registries, and clients are tested. Particularly, each combination of interaction between the web registries, service providers, and clients are tested to ensure the reliability of the web services as well as the web registries, service providers, and clients. This is important, as different service providers, registries, and clients can be implemented on diverse platforms using different technologies. Additionally, properly testing the interactions between the web registries, service providers, and clients must further ensure synchronization problems associated with the prior art.
Thus far, interactions between the web registries, service providers, and clients are typically performed by stand-alone computers or a network of computer resources. When using a stand-alone computer system, separate stand-alone computers are manually programmed to run tests selected by a user. Comparatively, if a network of computer resources is used, the user allocates a number of computer resources to test a particular interaction. Predominantly, the user manually selects a group of selected computer resources or adds and deletes computer resources to the network, programs the master computer system and the server, initiates the running of the user-selected test, and runs the test on the group of dedicated computer systems coupled to the server.
In either scenario, a heavy user interface is required to test the interactions, schedule the running of specific tests on the system resources, add and delete the system resources, keep track of the system resources and their respective hardware and software configurations, and maintain the system resources. Additionally, in either case, interactions are tested by dedicated system resources, designed to solely be used for testing the interactions between the registries, service providers, and clients.
By way of example, to test interactions scheduled to be performed synchronously, a test developer is required to manually initiate the testing process on a plurality of system resources following a particular menu. The menu provides the user the order in which specific tests are required to be run (e.g., synchronously, in parallel, or sequentially). Thus, testing a certain interaction requires the presence of a test developer at all times so that different tests can be initiated in accordance to the schedule set in the menu.
Furthermore, if an exception occurs during testing of an interaction between the registries, service providers, and clients, the testing process is halted. For instance, if an exception is occurred during testing an interaction between the registry and the client, the interaction is terminated, requiring that the client and the registry to be restarted. If restarting of the client and the web registry does not resolve the exception, the test developer on duty must communicate with the software programmer in charge of developing the test source code so as to resolve the exception.
Additionally, currently, if a system resource crashes or a response has not been received from a system resource during testing a particular interaction, testing the particular interaction continues indefinitely. In certain situations, to avoid such problems, testing the interaction is interrupted manually by the test developer present.
One significant limitation of the current state of testing the web services and interactions between the registries, service providers, and clients is the extent of human intervention and significant role of humans. Requiring the presence of test developers to manually initiate, schedule, and interrupt the testing is very costly, is a of waste of resources, not to mention, very time consuming. At times, human error further exacerbates this limitation. Another limitation involves wasting of computer resources, as the computer resources are solely dedicated to testing the web services and the interactions between the web registries, service providers, and clients.
In view of the foregoing, there is a need for a flexible methodology and system capable of selecting and utilizing dynamic, cross-platform computer resources to process multiple process-flow-based computer software processes using diverse technologies and platforms with minimal human intervention. | {
"pile_set_name": "USPTO Backgrounds"
} |
In process measurements technology or in industrial measurements technology, apparatuses for handling liquid samples, especially for automatic removal of a liquid sample from a sample-taking location, are especially used for monitoring the quality of applied or manufactured liquids and liquid mixtures. Examples of such apparatuses are automatic sample takers, which, at predetermined points in time, withdraw from the sample-taking location a liquid sample with a predetermined volume, and collect this in sample containers. The collected samples can later be further examined and analyzed in the laboratory. Sample takers are also frequently used when monitoring and optimizing the cleaning effectiveness of a clarification plant, when monitoring activation basins and the clarification plant outlet or for controlling filler metering.
Besides a sufficient metering accuracy, the most important requirements for so-applied apparatuses, especially automatic apparatuses, for handling of liquids—especially automatic sample takers—are robustness, ease of operation and the assurance of sufficient working and environmental safety. At the same time, the effort involved and especially the costs for manufacture and maintenance of such apparatuses should be kept as low as possible, even though such apparatuses, as a rule, make use of a large number of individual components.
Known in the state of the art are modularly embodied apparatuses for handling liquid samples, especially for removal of liquid samples from a sample-taking location. The modular construction is intended to make the apparatuses robust and flexible in form. At the same time, a modular construction facilitates the manufacture of such apparatuses, and permits a retrofitting of an existing apparatus through addition of further modules with new functionalities.
In the international publication WO 2007/057432 A1, a modularly constructed sample taker is described, which can optionally be expanded with an analysis module, and thus is retrofittable to an automatic analysis device. A cooling/temperature control module is also provided, which, like the analysis module, can be embodied as a retrofittable, modular, structural unit. The temperature control module is accommodated in a module housing, which, by means of an adapter unit (which can, for example, be composed of mutually engaging, push-in rails) can be releasably connected with the housing of the sample taker.
The sample taker described in WO 2007/057432 A1 includes, as supply and metering system, a sample withdrawal unit, which is composed of at least a suction hose, a pump and a distributor station for the liquids which are supplied by means of the pump. The sample withdrawal unit can likewise be embodied as a module. The sample withdrawal unit is a component of a wet space, which is separated from additional modules. As a component of the wet space (which forms, as a whole, one module), the sample withdrawal unit cannot easily be replaced with another sample withdrawal unit (for example, with a sample withdrawal unit which works according to another functional principle). This would mean a certain effort for modification of the wet space module. | {
"pile_set_name": "USPTO Backgrounds"
} |
A multilayered optical disc enables multiplexing and recording of multiple pieces of information therein in a perpendicular direction. For example, in a two-layer optical disc, a first layer and a second layer are formed with a spacer region being sandwiched by the first and second layers, and a recording surface in the first layer which is closer to a light irradiation surface of the optical disc is formed of a semi-transparent membrane in such a way that light can reach the second layer.
When changing the layer from which recorded information is to be read in playback of the above-mentioned multilayered optical disc, it is necessary to perform an interlayer movement (focus jumping) operation of focusing laser light from an optical pickup unit onto the multilayered optical disc in such a way as to cause the optical pickup unit to make a transition from a state in which the optical pickup unit focuses the laser light therefrom onto the recording surface in the first (or second) layer to a state in which the optical pickup unit focuses the laser light therefrom onto the recording surface in the second (or first) layer. This focus jumping operation is performed on the basis of zero clear detection of a focus error signal (referred to as an FE signal from here on) which is generated on the basis of the output of the optical pickup.
By the way, it is known that variations occur in the amplitude of the FE signal corresponding to each layer due to individual differences in the characteristics of the above-mentioned multilayered optical disc, an objective lens that constructs the optical pickup unit, and so on. Therefore, a problem is that although a threshold is provided for the FE signal corresponding to each layer and an acceleration or deceleration signal is furnished to an actuator used for the focus jump according to the threshold, the acceleration or deceleration signal does not have an appropriate value because of variations in the amplitude of the FE signal and therefore the optical pickup unit cannot perform a focus jump to the desired recording layer in a short time.
An optical disc driving device that, in order to solve this problem, by correcting the amplitude of the FE signal corresponding to each layer in such a way that the amplitude has an identical value, and then applying a threshold to the corrected signal amplitude, can carry out a focus jump correctly even if there are variations in the characteristics of the focus actuator of the optical pickup unit and there is a variation in the distance between the plurality of recording surfaces is known (for example, refer to patent reference 1). [Patent reference 1] JP,2000-298846,A
A problem with the technology disclosed by above-mentioned patent reference 1 is, however, that it is necessary to measure the amplitude of the FE signal corresponding to each layer correctly, and, when, for example, making a focus search by rotating a disc having a surface deflection, it is difficult to carry out the measurement itself because the FE signal corresponding to the same layer appears in synchronization with the rotational cycle, as shown in, for example, FIG. 9(b).
FIGS. 9(a) and 9(b) are views showing a comparison between the FE signal corresponding to each layer of the multilayered optical disc in a case in which the multilayered optical disc has a surface deflection and the FE signal in a case in which the multilayered optical disc has no surface deflection. It is well known that the amplitude of the FE signal is zero when the focal position is far away from the recording layer and exhibits an S-shaped curve as the focal position gets close to the recording layer, and further becomes zero when the focal position reaches the recording layer. In the example shown in FIG. 9(a), because it can be recognized that the S-shaped curve which appears for the first time with respect to the lens position corresponds to the L0 layer (i.e., the first recording layer) and the S-shaped curve which appears for the second time with respect to the lens position corresponds to the L1 layer (i.e., the second recording layer), the amplitude of the FE signal corresponding to each layer can be measured. In contrast, in the example shown in FIG. 9(b), because the S-shaped curve appears several times with respect to the lens position, it cannot be recognized that which S-shaped curve corresponds to which one of the layers, and therefore the amplitude of the FE signal corresponding to each layer cannot be measured.
The present invention is made in order to solve the above-mentioned problems, and it is therefore an object of the present invention to provide an optical disc driving device that implements a stable focus jump even if there are individual differences in the characteristics of a multilayered optical disc, an objective lens which constructs an optical pickup unit of the optical disc driving device, and so on. | {
"pile_set_name": "USPTO Backgrounds"
} |
Field of the Invention
The present invention relates to a tire mounting device for fitting a tire bead onto a rim of a wheel.
Description of Related Art
Hitherto, there has been known a tire mounting device for fitting a tire bead onto a rim of a wheel by pressing a tire along a circumferential direction of the tire under a state in which the tire is temporarily engaged on the wheel in an oblique posture. For example, a tire mounting device proposed in Patent Literature 1 includes a tire bead press roller and a guide roller, which are caused to circle along a circumference of the wheel. Thus, the guide roller guides an end portion of the tire bead to an outer circumferential position of the wheel, while the tire bead press roller following the guide roller presses a side surface of the tire bead (sidewall) from above, thereby fitting the tire bead onto the rim.
Further, a tire mounting device proposed in Patent Literature 2 includes, instead of the above-mentioned guide roller, a bead guide plate formed into an arc shape to guide the tire bead to the outer circumferential position of the wheel while sliding the tire bead on a surface of the bead guide plate. | {
"pile_set_name": "USPTO Backgrounds"
} |
Data deduplication is a technique used to increase storage capacity of a storage device. By using data deduplication, a redundant copy of a unique data chunk is identified and removed from the storage device. Thus, a single copy of the unique data chunk is stored in the storage device. | {
"pile_set_name": "USPTO Backgrounds"
} |
Human joints, in particular the knee, hip and spine, are susceptible to degeneration from disease, trauma, and long-term repetitive use that eventually lead to pain. Knee pain, for example, is the impetus for a wide majority of medical treatments and associated medical costs. The most popular theory arising from the medical community is that knee pain results from bone-on-bone contact or inadequate cartilage cushioning. These conditions are believed to frequently result from the progression of osteoarthritis, which is measured in terms of narrowing of the joint space. Therefore, the severity of osteoarthritis is believed to be an indicator or precursor to joint pain. Most surgeons and medical practitioners thus base their treatments for pain relief on this theory. For example, the typical treatment is to administer pain medication, or more drastically, to perform some type of joint resurfacing or joint replacement surgery.
However, the severity of osteoarthritis, especially in the knee, has been found to correlate poorly with the incidence and magnitude of knee pain. Because of this, surgeons and medical practitioners have struggled to deliver consistent, reliable pain relief to patients especially if preservation of the joint is desired.
Whether by external physical force, disease, or the natural aging process, structural damage to bone can cause injury, trauma, degeneration or erosion of otherwise healthy tissue. The resultant damage can be characterized as a bone defect that can take the form of a fissure, fracture, lesion, edema, tumor, or sclerotic hardening, for example. Particularly in joints, the damage may not be limited to a bone defect, and may also include cartilage loss (especially articular cartilage), tendon damage, and inflammation in the surrounding area.
Patients most often seek treatment because of pain and deterioration of quality of life attributed to the osteoarthritis. The goal of surgical and non-surgical treatments for osteoarthritis is to reduce or eliminate pain and restore joint function. Both non-surgical and surgical treatments are currently available for joint repair.
Non-surgical treatments include weight loss (for the overweight patient), activity modification (low impact exercise), quadriceps strengthening, patellar taping, analgesic and anti-inflammatory medications, and with corticosteroid and/or viscosupplements. Typically, non-surgical treatments, usually involving pharmacological intervention such as the administration of non-steroidal anti-inflammatory drugs or injection of hyaluronic acid-based products, are initially administered to patients experiencing relatively less severe pain or joint complications. However, when non-surgical treatments prove ineffective, or for patients with severe pain or bone injury, surgical intervention is often necessary.
Surgical options include arthroscopic partial meniscectomy and loose body removal. Most surgical treatments conventionally employ mechanical fixation devices such as screws, plates, staples, rods, sutures, and the like are commonly used to repair damaged bone. These fixation devices can be implanted at, or around, the damaged region to stabilize or immobilize the weakened area, in order to promote healing and provide support. Injectable or fillable hardening materials such as bone cements, bone void fillers, or bone substitute materials are also commonly used to stabilize bone defects.
High tibial osteotomy (HTO) or total knee arthroplasty (TKA) is often recommended for patients with severe pain associated with osteoarthritis, especially when other non-invasive options have failed. Both procedures have been shown to be effective in treating knee pain associated with osteoarthritis.
However, patients only elect HTO or TKA with reluctance. Both HTO and TKA are major surgical interventions and may be associated with severe complications. HTO is a painful procedure that may require a long recovery. TKA patients often also report the replaced knee lacks a “natural feel” and have functional limitations. Moreover, both HTO and TKA have limited durability. Accordingly, it would be desirable to provide a medical procedure that addresses the pain associated with osteoarthritis and provides an alternative to a HTO or TKA procedure.
In current practice, surgeons typically “eyeball” (i.e., visually estimate) the target site on a bone to be repaired. Most conventional targeting and location methods are relatively crude and provide little guidance to a surgeon during the actual surgical procedure. Accordingly, it would be desirable to provide methods and instruments in which the area near a bone defect can be easily located and provide a reference framework that can be used in a surgical procedure irrespective of the approach. Furthermore, in some situations where pinpoint accuracy is not critical or necessary, a navigation system that can indicate an area sufficiently near the bone defect in a quick and reliable manner would be highly beneficial to the clinician.
Accordingly, it is desirable to provide instruments that allow fast, easy, and repeatable navigation to, and positioning of devices in, an area sufficiently near a bone defect to be treated. It is further desirable to provide instruments that do not obstruct access to the working area around the target site, and allow as clear a view as possible for the clinician. | {
"pile_set_name": "USPTO Backgrounds"
} |
Aspects are related generally to integrated circuit testing, and more specifically to non-destructive recirculation test support for integrated circuits.
When developing integrated circuit systems, resulting devices need to be tested and faults diagnosed. A common diagnostic approach in industry uses post-test software algorithms that run on fail data collected at a test system. To generate the data, patterns can be applied to a device under test and the responses collected. Failing responses can be fed into design automation software which analyzes the fail data and gives suspected callouts for the defect detected. A set of faults is associated with each design. A typical fault model is the “stuck-at” fault model, which includes both a stuck-at-1 and stuck-at-0 fault. The design is typically a gate-level representation (AND, OR, XOR, etc.), and the faults are applied at the inputs and outputs of each logic block. Based on a complete list of faults, diagnostic software typically produces a callout identifying the most likely faults to explain the faulty response. The goal is to have a precise enough callout so that physical failure analysis can be done on the device under test to identify the physical defect and determine the root cause.
Generally, there are two types of diagnostic techniques: cause-effect analysis techniques and effect-cause analysis techniques. Cause-effect techniques depend on stored symptoms caused by possible faults and use the observed responses to locate the fault. A fault dictionary approach is one such example. Problems with this approach, especially for large chips, can include excessively long simulation run time with prohibitively large memory requirements and ineffective physical and electrical failure analysis due to low diagnostic resolution. In contrast, effect-cause techniques do not depend on pre-stored data but instead process the response obtained from the device under test to determine the possible faults that generate the response. Effect-cause algorithms are less processing resource intensive and are well suited to fault diagnostics. Software diagnostic techniques are typically faster than other methods; however, fault candidates can be wrong or there can be too many candidates with low scores. A fault with a low score is one with a low probability of explaining the failure. This can result from incomplete fail data, un-modeled fault types such as path delay and bridging faults, and faults in areas of logic that are not fully represented in the fault model (such as clock logic).
To support built-in testing of logic circuits, some integrated circuit designs use a combination of scan channel chains of various lengths feeding into individual test register inputs that are processed in parallel. The test registers and scan channel chains typically operate by continually shifting values through the scan channel chains and test registers which results in destructive read/unload operations and makes it difficult to restore the test configuration to an intermediate state. All of these test techniques have resulted in a need for better, improved test support systems and methods. | {
"pile_set_name": "USPTO Backgrounds"
} |
A vehicle may be equipped with an accelerator pedal for translating a driver torque request into a powertrain torque request. The powertrain torque request may be provided via an engine or an engine cooperating with a motor to propel the vehicle. By applying or depressing the accelerator pedal, a driver may request additional torque from the vehicle. Vehicle torque may be reduced via releasing or partially releasing the accelerator pedal, thereby allowing the accelerator pedal to return to an initial or base position.
An accelerator pedal or accelerator pedal sensor may degrade over a vehicle's life cycle. The accelerator pedal and/or accelerator pedal sensor may output a signal having a value higher or lower than is expected when the accelerator pedal or accelerator pedal sensor is degraded. Alternatively, or in addition, the accelerator pedal may not travel as freely as is desired during some conditions. Consequently, it may be possible for the accelerator pedal and/or accelerator pedal sensor output to be a substantially constant value representing an accelerator pedal position other than base accelerator pedal position during a condition where it is expected that the accelerator pedal is in its base position. Whether or not the accelerator pedal and/or accelerator pedal position sensor is degraded, it may be desirable to be able to stop the vehicle during conditions of accelerator pedal degradation while a driver is applying vehicle brakes.
If a driver applies vehicle brakes during periods of accelerator pedal degradation, brake performance may be reduced over time. Further, vehicle braking system components may degrade during such conditions. Therefore, it may be desirable to provide sufficient braking power to stop a vehicle when an accelerator pedal demand is requested without significantly increasing braking system degradation.
The inventors herein have recognized the above-mentioned disadvantages and have developed a method for operating a vehicle, comprising: reducing powertrain torque in response to a speed of a vehicle being greater than a speed at which vehicle brakes have capacity to fully stop the vehicle at a present temperature of vehicle brakes.
By reducing powertrain torque in response to speed of a vehicle being greater than a speed at which vehicle brakes have capacity to fully stop the vehicle at a present temperature of vehicle brakes, it may be possible to provide a desired level of vehicle braking without causing significant brake component degradation. Further, in some examples, a transmission of the vehicle may be shifted from a forward gear into neutral so as to further reduce an amount of braking force to stop a moving vehicle. In these ways, powertrain power may be reduced to lower the possibility of brake system component degradation while providing braking power sufficient to stop the vehicle.
The present description may provide several advantages. In particular, the approach may reduce the possibility of brake system component degradation. Additionally, the approach may provide a desired amount of braking power to stop a vehicle during conditions of accelerator pedal and/or accelerator pedal sensor degradation. Further, the approach compensates for driving conditions in an effort to provide more consistent vehicle braking during conditions of accelerator pedal and/or accelerator pedal sensor degradation.
The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings.
It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a recording disk drive such as a hard disk drive (HDD). In particular, the invention relates to a recording disk drive comprising a recording disk and a ramp member located at a location outside the recording disk.
2. Description of the Prior Art
A ramp member is often incorporated in a HDD, for example. The ramp member defines a guiding passage extending along a path of movement of a load tab. The load tab is usually attached to the tip end of a head actuator. When a magnetic recording disk stands still, the ramp member receives the load tab at an inoperative position on the guiding passage. The guiding passage includes a first flat surface parallel with the surface of the magnetic recording disk. An inclined surface extends from the outer end of the first flat surface, and is inclined towards the plane of the magnetic recording disk in the direction of the inoperative position. A second flat surface is connected to the outer end of the inclined surface. The inoperative position is defined on the second flat surface.
A so-called latch mechanism is often incorporated in the HDD. The latch mechanism includes a restriction member swinging around a predetermined support shaft. Here, assume that an impact acts on the enclosure of the HDD around a support shaft of the head actuator when the magnetic recording disk stands still. The head actuator is caused to swing around the support shaft. At the same time, the restriction member is caused to swing. The restriction member gets into the path of movement of the head actuator. When the load tab moves from the inoperative position to a restriction position on the guiding passage, the restriction member catches the head actuator. The load tab is thus held at the restriction position. Contact is prevented between the head slider and the surface of the magnetic recording disk.
In the aforementioned HDD, when the restriction member catches the head actuator, the load tab stays at the first flat surface. Since the first flat surface is located further from the surface of the magnetic recording disk than the second flat surface, the head suspension largely deforms as compared with the case where the load tab is held at the inoperative position. In other words, the head suspension suffers from a larger load. It is desirable to suppress the load on the head suspension as much as possible. | {
"pile_set_name": "USPTO Backgrounds"
} |
Among the filter assemblies commonly used for removing solid particles from a fluid are those having a plurality of tubular filter means suspended in a housing wherein the tubular filter means are closed at the bottom and open at the top. Some examples of such filter assemblies are disclosed in U.S. Pat. Nos. 2,954,873, 3,169,109, 3,228,528, and 3,356,215; the disclosures of which are incorporated herein by reference.
In those types of filter assemblies, the tubular filter means are suspended from a partition which divides the housing into a lower inlet portion and an upper outlet portion. The partition has openings in it which allow fluid to flow from inside the filter means to the upper outlet portion of the housing. Filtering is accomplished with those filter assemblies by introducing the solids-containing fluid into the lower inlet portion of the housing. The fluid flows through the walls of the tubular filter means and up into the upper outlet portion of the housing. The solids removed remain on the outside of the tubular filter means.
Such filter assemblies have found a wide range of uses, including, for example, the filtering of boiler feedwater, cooling water pharmaceutical process solutions, salt water, and refinery process streams, such as coker gas oil or heavy vacuum gas oil streams. In some applications a filter cake is applied to the outside of the tubular filter means.
Generally, in all applications of such filter assemblies at some point in time the accumulation of solids on the outside of the tubular filter means becomes so great that it is necessary to backflush the tubular filter means. The backflush generally involves flowing filtrate or other backflush fluid in a reverse fashion through the filter means while the filtering is shifted to another filter assembly.
It is desirable to be able to clean the filter means as quickly as possible with a minimum amount of backflush fluid. It has been observed that if one tries to backwash all the tubular filter means simultaneously, more backflush liquid is needed than is generally desirable.
An object of the present invention is thus to provide a means for backflushing a plurality of tubular filter means to obtain adequate cleaning of the filter means with smaller quantities of backflush fluid.
Still another object of the present invention is to provide a means for controlling the backflush that is less complex, more reliable, and more economical than many means of the prior art.
Other aspects, objects, and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
} |
A high-frequency package on which a high-frequency semiconductor device, which operates in a high frequency band such as a microwave band and a millimeter-wave band, is mounted is often housed in a cavity that is airtightly and electrically shielded with a metallic frame or the like, considering environment resistance, operational stability, corrosion resistance, and the like.
Patent Document 1 discloses a technique in which a control signal line is wired on a dielectric multilayer substrate, a metallic frame is arranged on the dielectric multilayer substrate, and a microwave integrated circuit is mounted in the metallic frame, thereby improving input/output isolation of the integrated circuit, and in which airtight sealing is enabled by welding.
Patent Document 1: Japanese Patent Application Laid-open No. 2001-203290 | {
"pile_set_name": "USPTO Backgrounds"
} |
Children enjoy pitching, throwing, kicking and swinging at balls especially if the ball bounces back for more practice. Often times they engage in these physical activities indoors where they can be harmful to themselves or their surroundings. A few safe indoor target games have been developed but they are not selling well in today's toy market when these simple target toys are competing with fancy electronic toys. The result is the problem of the child practicing indoors with outdoor equipment not safe for indoor use. Furthermore, parents and children enjoy decorating the children's bedroom or playroom with agreeable artwork that will not mar the wall or door.
U.S. Pat. No. 3,941,383 (Clarke), issued Mar. 2, 1976 discloses a sports-related target game with a printed baseball player on the target. The target must be attached to the wall with a nail or screw hook or other similar object that will mar the wall. Clarke shows a knit nylon and urethane foam wall-hanging target having a loop threaded material, and a ball partially covered by the hook-threaded fastening materials. The loop-threaded and hook-threaded fastening materials are known as VELCRO™. The hook fabric on the ball causes lint to stick to it and also causes the ball to get caught in other toys or material found in the child's room.
The present applicant solved many of the inherent problems in prior art target games in the U.S. Pat. No. 5,836,588 (Gerson) issued Nov. 17, 1998. The sports related target game is printed on a self-adhesive mural portraying characters playing an action sport, a loop-threaded stuffed ball corresponding to the sport portrayed in the mural, and a hook threaded fabric target attached to the mural in an appropriate location to facilitate the fantasy of actually play in a game with the figures on the wall mural. The ball is covered in the loop-threaded fabric that does not stick to common material or surfaces found in a child's room or play area. The mural is decorative and enhances the appearance of the child's room. The child can continue play for unlimited time either alone or with friends. The challenge for the child is to get the ball to stick on the mural in the section that is covered with the loop-threaded material. This creates a feeling of instant success. The artwork on the mural engages the child's imagination so that pretending to be the pitcher, soccer forward or quarterback for example, encouraging fun role playing activities. However, this game could be enhanced with audible and visual sound effects to produce an even more exciting game.
Many toy inventors realized the limits of selling the simple target game in the competitive market arena. Prior art electronic target games tend to be complicated to produce and cumbersome for the owner.
For example, U.S. Pat. No. 5,358,253 (Chen), issued Nov. 4, 1994, describes a light and sound emittable darts-board. In this invention the electronics are bulky and the board must be hung on the wall on a nail, screw, hook or other similar object that will mar the wall. There are three layers used to create the necessary space for the electronics. Thus the target is heavy and must be securely fastened to the wall for safety. The inventor has adults in mind when creating this dart game to be used in bars as he suggests. The theme is limited to simple darts and a target that does not invite a child to use his imagination as one could in a sports-play mural.
U.S. Pat. No. 5,326,094 (Quinn), issued Jul. 5, 1994, describes an audio sports game that utilizes audio messages to present a functional setting for the person playing the game. In order for the mechanism to trigger an audio message, an object must pass through a 3D structure and hit a mechanical switch as it passes through. To mass-produce a 3D object is more expensive than to mass-produce a 2D surface with a mural creating the illusion of a 3D scene that is printed on the front surface. Also, a mechanical switch has a relatively short life span.
U.S. Pat. No. 5,566,934 (Black, et al.), issued Oct. 22, 1996, describes a baseball trainer that includes a free-standing target apparatus having a plurality of panels for indicating a “strike” or a “ball”, which indication is communicated to a microcomputer in a console adjacent to the practicing player. Additional features allow the trainer to calculate pitching speed and to audibly report it to the player. Black's trainer is a complicated and expensive apparatus designed for rugged commercial use, therefore not appropriate for the cost-competitive consumer toy market. Referring to Black's FIG. 4, a limitation of its design can be seen in that a strike panel (22) and ball panel (34) are mounted separately from each other, suspended on double hinges (23, 25) from a back panel (26). The panels register a hit by a ball (B) providing the hit has sufficient impact to move the panel enough to compress a spring (28, 31, 32) and a switch (27, 29, 30) that are both positioned between the strike or ball panel and the back panel. The ball panel surrounds the strike panel and is therefore rather large. According to Black's detailed description: “ . . . it is advisable to mount more switches (29, 30) at divers locations behind the ‘ball’ zone panel (24), because of its larger size, to ensure that a ball hitting anywhere on the ‘ball’ zone panel (24) will result in a signal.” | {
"pile_set_name": "USPTO Backgrounds"
} |
With the proliferation of digital audio and video devices, it has become necessary to establish a high speed serial communication mechanism that is capable of allowing efficient and fast transfer of audio/video (A/V) data between devices. IEEE 1394 has so far been a successful candidate for this purpose.
While the transmission of A/V data using industry standard such as IEEE 1394 is well known, the storage of A/V data on modern computing devices is becoming an important issue. Modem computing devices are rapidly moving toward offering various kinds of functionality and features in an integrated manner. For example, a personal computer (PC) nowadays generally contains a myriad of computer programs which offer a variety of functionality, such as word processing programs as well as computer programs which are capable of processing and playing video and audio data. As a result, there is a need to store both A/V data and non-A/V data and both types of data are typically stored on a computer hard disk together.
To store data on the hard disk or other media, a file system is generally required to be in place to organize files and accomplish a number of file-handling tasks such as file creation, deletion, access, save and update. Furthermore, it is preferable and common practice for a file system to have a directory structure which organizes and provides information about all the files stored in the file system. Typically, a file system is capable of storing both A/V and non-A/V data.
A/V data and non-A/V data, however, are fundamentally different in a number of respects. For example, the size of A/V data files is relatively large when compared to the size of non-A/V data files. As a result, handling files of varying sizes in an efficient manner becomes a challenging issue.
Moreover, since A/V data files are generally very large, it is usually not possible to store an entire A/V data file in a temporary storage area such as the random access memory (RAM). Therefore, due to the large size of an A/V data file, efficient random access of A/V data within the A/V data file also presents a problem.
Furthermore, the retrieval and processing of A/V data are subject to relatively stringent time and order-related constraints. Such constraints are necessary to prevent the corruption of A/V data and avoid potential glitches. For example, in order to provide a smooth presentation of video images, A/V data need to be retrieved and processed quickly and continuously in the correct sequential order. Otherwise, the video images might become choppy and incomplete. Hence, it would be desirable to develop and provide an application programming interface between an audio/video controller and a file system capable of handling a mix of A/V and non-A/V data so as to allow A/V data to be stored, retrieved and processed in an efficient manner.
Moreover, changes made to the internal mechanics of a file system should ideally be apparent to any external devices that need to communicate with the file system. This would obviate the need to make changes to the external devices every time the internal mechanics of the file system is changed. Thus, it would also be desirable to develop and provide an application programming interface between an audio/video controller and a file system so that the audio/video controller is not affected by changes to the file system. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present disclosure relates to a navigation apparatus and a storage medium.
In recent years, development of navigation technology which performs navigation of a route has been made for a user who walks, runs, or operates a car, ship or the like. As an example of this, technology has been developed, for a user who is driving a car, which determines a route to be guided based on whether the route is shaded or in the sun, from the viewpoint of suppressing energy consumption and a concern for the environment.
For example, JP 2012-47456A discloses technology which calculates a sunlight amount and determines a route, based on the speed limit of the route and factors which can cause delays such as temporary stops, in addition to sunlight information based on the position of the sun, the orientation of the road, surrounding buildings or the like.
Further, JP 2009-264902A discloses technology which specifies a guidance route, in accordance with the total ultraviolet ray exposure amount calculated by using a database in which an ultraviolet ray exposure amount is stored for each predetermined section.
Further, JP 2007-205946A discloses technology which performs guidance by searching again for a route which satisfies a search condition specified by a user, in the case where circumstances occur which are different from those expected at the time of performing a route search. | {
"pile_set_name": "USPTO Backgrounds"
} |
Existing flywheels for energy storage are sometimes constructed such that the rotating mass of the flywheel rotates inside a chamber containing a vacuum. Operating the rotating mass inside a vacuum is advantageous since it reduces energy losses due to air resistance also known as windage. However, in order to transfer energy into and out of the rotating flywheel mass, a coupling means is required. Some existing flywheels use a rotating shaft passing through a rotating seal in the vacuum chamber to couple torque from an energy source to the flywheel energy storage means. Rotating seals are never perfect, however, since they inevitably leak and therefore require an environmental management system to be coupled to the vacuum chamber in order to maintain the vacuum despite leakage. Furthermore, the seals become more “leaky” with age and as rotational speed increases, and also wear more quickly at higher speeds. The mass, volume and cost of such an environmental management system is undesirable. The use of rotating seals is therefore undesirable.
Magnetic couplings can be used with flywheels to transfer torque through a vacuum chamber wall, thereby obviating the need for rotating seals. For example, a magnetic gear used to couple force between movable members, for example drive shafts, is described in International Patent Application PCT/GB2010/000590, filed by Ricardo UK Limited, the entire contents of which are incorporated herein by reference. A rotational magnetic gear 100 as described in PCT/GB2010/000590 is shown in FIG. 1a herein. The device has first and second movable members 110, 120, each having a circumferentially distributed array of alternating magnetic poles 115, 116, 125, 126. Magnetic flux is coupled between the pole arrays by coupling elements 130. The coupling elements 130 minimise the air gap 150 between the moveable members, especially when a membrane 140 is present in the air gap. FIG. 1b shows the lines of magnetic flux 160, 170 in a portion of the arrangement of FIG. 1a. The membrane 140 allows the two movable members 110, 120 to be operated in different respective atmospheric conditions. For example, one member may be operated in a vacuum. As one member rotates in a clockwise direction, the other member counter rotates in an anticlockwise direction as the lines of magnetic flux 170 pass from one array of poles to the other array of poles through the coupling elements 130. No physical connection is required therefore the use of rotating seals can be eliminated which is advantageous in that it allows expensive environmental management systems to also be eliminated. The membrane 140 of course needs to be strong enough structurally to withstand the forces exerted by air pressure.
Although not limited to flywheel applications, the arrangement shown in FIG. 1a can be advantageously used to couple a high speed flywheel operating inside a vacuum enclosure to a lower speed drive shaft under atmospheric pressure since, if the number of poles of the first member is dissimilar to the number of poles on the second member, a gearing effect results which allows the driveshaft in atmospheric pressure to operate at a lower speed than the flywheel, thereby reducing windage losses. However, in order to achieve a high gearing ratio, the dimensions of the magnetic poles on one of the members must be made as small as possible in order to fit as many as possible in. This, coupled with the need to make the whole assembly as compact as possible, dictates that the coupling elements 130 should also be relatively small. Further, in order to maximise the transfer of flux and thereby maximise the torque capacity of the magnetic gear coupling, the device may be extended along its axial length so that it is generally elongate cylindrical. This can mean that the coupling elements 130 have a relatively long length dimension and a relatively narrow cross sectional area. The coupling elements are therefore prone to suffering from a lack of rigidity and can bend, move, or vibrate. This can lead to non-optimal functioning of the device and/or eventual degradation and/or failure. It is also difficult to manufacture such a device since careful alignment is necessary and many production steps are needed to individually assemble the coupling elements into the correct position and hold them there.
The angular offset between the input and output shafts of a magnetic gear such as the one shown in FIG. 1a varies according to the torque applied and to the torque coupling capacity of the magnetic gear at a given meshing position. Such variation of the torque coupling capacity with meshing position will result in a torsional vibration in the shafts. This can reduce the life of the associated mechanical components, and/or can result in failure and/or disengagement. This is an especially serious problem if the rotational speed is such that the frequency of the torsional vibration coincides with a resonance of the mechanical system. Therefore it would be advantageous if the variation in torque coupling capacity of a magnetic gear could be reduced or eliminated. This would allow smaller, cheaper, magnet arrays to be used, since the minimum torque coupling capability would then be much closer to the mean torque coupling capability. Torsional vibration of the shafts would also be reduced, allowing cheaper, lighter and smaller components to be used. A flywheel energy storage system employing such smaller, cheaper and lighter components would have a higher energy storage density.
Existing magnetic couplings suffer from further disadvantages. For example, in existing systems where magnetic coupling is used to transfer energy into and out of a rotating flywheel situated in a vacuum to and from means outside that vacuum, a cooling arrangement is required in the vacuum. Such a cooling arrangement acts to reduce heat caused by operation of the flywheel and magnetic coupling, including heat generated due to variation in the magnetic field of the magnets on the flywheel side of the coupling. Such cooling arrangements can be complex, adding to the overall complexity, bulk and expense of the system. Existing magnetic coupling arrangements also suffer from general fatigue over time, and in particular there is a tendency for the rotating magnets to shift out of place over time due to the effects of rotation. Similarly, any stationary electromagnetic poles provided between the two respective rotating magnetic members can encounter slip and fatigue over time.
There is no known coupler using rotatable magnets which can be used to transfer energy into an out of a flywheel situated in a vacuum in an efficient, cost effective and compact manner.
An invention is set out in the claims.
According to an aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel and wherein the magnetic strength of a first magnet arranged on the first movable member exceeds the magnetic strength of a second magnet arranged on the second movable member. The first magnet may be larger than the second magnet. The first magnet may be a sintered magnet and/or the second magnet may be a bonded magnet. As a result, the magnetic field across the coupling apparatus is skewed so that losses due to variation in magnetic field occur mainly in the vicinity of the second moveable member, away from the flywheel.
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The coupling apparatus further comprises a retainer for physically retaining the one or more magnets arranged on the first movable member. The retainer may take the form of a winding which can be wound around an outer surface of the magnets on the first movable member. Alternatively it may take the form of a sleeve which can be fitted over an outer surface of the magnets on the first movable member. The retainer may be formed from a retaining material and an adhesive material, wherein the adhesive material may include fragments of other materials embedded therein for the provision of electronic stress relief.
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The coupling apparatus further comprises a membrane intermediate the first and second movable members, said membrane comprising a groove or recess for locating one or more magnetic poles. The membrane may be formed from Polyether ether ketone (PEEK).
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The coupling apparatus further comprises a liner intermediate the second movable member and the one or more magnets arranged thereon. The liner may comprise one or more discontinuous sections and/or may be formed from a suitable material such as Somaloy.
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The first and second movable members are rotatable about a common rotation axis, with the second movable member being provided radially outward of the first movable member. The second movable member is formed from a material with low electrical conductivity and low permeability. For example it is formed of Peek or Glass fibre. The second movable member may comprise first and second sections formed from first and second respective materials.
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The apparatus is provided inside a housing or casing, which can also house the flywheel to which the first movable member is coupled. A formation on an inner surface of the casing is arranged to provide magnetic flux shielding during operation of the coupling apparatus.
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The first and second movable members are rotatable about a common rotation axis, with the second movable member being provided radially outward of the first movable member and connected to a shaft at a first end. An end plate is provided at a second end of the second movable member, substantially axially opposite the shaft.
According to another aspect, a coupling apparatus for transferring energy to or from a flywheel is provided. The coupling apparatus comprises first and second movable members, each having one or magnets arranged thereon, wherein the first movable member is arranged to be coupled to a flywheel. The apparatus further comprises a stator, between the first and second movable members. Means is provided on the stator, and/or on at least one of the movable members, for enhancing air flow around the apparatus. The means may comprise a scrolling or groove. The means may comprise a projection such as a fin or a blade. A plurality of such projections may be provided. The means may comprise an opening or channel through the stator and/or through the second movable member.
According to another aspect, a method for constructing any coupling apparatus as described herein is provided. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention generally relates to signal coding and, more particularly, to multi-dimensional coding for high-density storage media applications.
2. Background of the Invention
Even though already a multi-billion dollar industry, the digital recording industry is expected to expand further in the future as an almost insatiable appetite for more storage continues to grow. This increase is partly fueled by the steady move towards digital systems, as has happened for example in the audio industry with the replacement of the analog Long Play (LP) disk by the digital Compact Disk (CD). Digital disk recording systems include magnetic and optical recording, the latter mainly for read only applications. Whether optical or magnetic, one of the main goals of ongoing research is to increase areal density in bits per unit area.
Modulation codes, for most recording systems, focus on increasing linear density through the reduction of Inter-Symbol Interference (ISI). Further increases in storage density are potentially available by reducing track width and increasing track density. However, this results in undesirable Inter-Track Interference (ITI) and a reduction in signal-to-noise ratio (SNR). Consequently, typical magnetic recording systems have linear-to-track density ratios of only 25 to 1. Head misalignment or side reading (cross talk) that occurs between the read head and adjacent track data causes ITI. This has been acknowledged as an important noise source that can be alleviated by employing sophisticated signal processing techniques whilst reading several adjacent tracks simultaneously with a multi-track head. An additional advantage of reading multiple tracks in parallel can be gained by employing two-dimensional run-length limited (d, k) modulation codes. These have attracted much attention in recent years as a means of increasing storage capacity by relaxing the timing constraint, k, along the tracks. Timing recovery is then achieved in a joint manner from information taken across a number of tracks.
Currently, the storage capacity of media such as, for example, a Hard Disk Drive (HDD) or an optical drive is limited by the state of the art of head, media and write technology. Contiguous media provides the best opportunity to increase storage space using the best cost metrics. One of the vexing problems in media storage is the inability of magnetic media to handle transition flux changes in excess of 500-800 Kbpi due to overwrite issues.
Coding and other methods and apparatus have been proposed to reduce the number of such transitions. However, all of such existing approaches suffer from one or more deficiencies. For example, transition detection is performed by peak detection methods that employ Analog-to-Digital Converters (ADCs), thereby increasing power consumption, which is not ideal for Microdrive and other portable media applications. Further, there is significant room for improvement in the current capacities of 1.3 bits per transition.
Multi head and multi track combinations along with the new perpendicular recording techniques have been used to increase the capacity of storage mediums. These approaches are expensive and generally will suffer from reliability issues due to the increased number of heads as well as the characteristics of the new media used in the perpendicular recording system.
Accordingly, it would be desirable and highly advantageous to have a coding method and apparatus for high-density storage media applications that overcome the above-described deficiencies of the prior art. | {
"pile_set_name": "USPTO Backgrounds"
} |
Historically, normal lumber construction utilizes lumber members and nails that are used to construct a building structure, such as, for example, a house. Lumber constructed structures are built by hand, but the process is slow and requires skilled labor such as highly trained carpenters and other skilled professionals. Such construction can require many hours of work in the outside elements (such as rain, snow. etc.), use a natural resource that can be of limited supply and may result in a structure that is less energy efficient because of inconsistencies in the quality of the build. An alternative approach employs steel studs. This approach also suffers from limitations in that the steel studs are difficult to work with and are good thermal conductors of heat through walls and roofs.
Structural insulated panels (SIPs) are a modern building material used in home and other modular building construction. Several factors have hampered the wide-spread use of SIPs in current building construction. SIPs require a substantial amount of pre-planning in order to result in an efficient construction process. This is because SIPs are not easily handled or customized in the field at a construction site. For example, in order to cut or otherwise modify SIP, special tools are required that may not be easily utilized in the field. Also, more precise planning and building techniques may be needed because SIPs are difficult to modify in the field. A further complicating factor is that SIPs are usually heavy and generally require the use of heavy equipment such as cranes. | {
"pile_set_name": "USPTO Backgrounds"
} |
Traditionally, the whereabouts of animals have been controlled by erecting physical barriers such as walls or fences at the site of a boundary the animal is to be prevented from crossing. Such barriers must not only be high enough to prevent the animal from jumping over and dense enough to prevent the animal from passing through any gaps but also substantial enough to withstand attempts by the animal to breach the barrier by physical force. The latter requirement is a serious limitation in that in addition to requiring considerable time and labor to erect, substantial physical barriers are often impracticable due to shortage of materials suitable for their construction.
Those limitations have been overcome to some extent by the development of avoidance-inducing physical barriers, of which, barbed wire and high voltage charged fences are well-known examples. Rather than relying solely on physical strength to defeat attempted breaches, animals quickly learn that contact with such barriers is associated with an aversive stimulus such as being shocked or pricked by sharp barbs. They therefore avoid repeated or sustained attempts to breach them. Physical barriers of the avoidance-inducing type have permitted the fencing of large areas with the expenditure of only a fraction of the time, effort and materials requirements which had previously been necessary. However, avoidance-inducing physical barriers also suffer from some important limitations.
First, like all physical barriers, posts and wires or other above-ground structures are required to erect an avoidance-inducing physical barrier. In some applications, such as the confinement of household pets or guard dogs within a property line, these structures can be unsightly and are sometimes forbidden by deed restrictions or local regulations. Like all physical barriers, avoidance-inducing physical barriers are non-selective. A physical barrier sufficient to control the whereabouts of a particular animal also tends to impede the ingress and egress of persons or other animals except at locations where a gate may be provided. Moreover, the animal can traverse the barrier if the gate is inadvertently left open. Electrified or barbed wire fences intended for controlling the whereabouts of animals can also shock or injure persons, especially young children.
Various electronic systems which do not require the erection of above-ground barrier structures and which are selective in their operation are also known. In these systems, selectivity is achieved by equipping only the animal (or animals) whose whereabouts are to be controlled with an electronic unit capable of sensing when the animal moves into predetermined proximity of a defined boundary and then delivering one or more aversive stimuli to deter the animal from traversing the boundary. Such stimuli commonly comprise an electric shock either alone or in combination with an advance audible tone. Until the advent of the present invention, prior art electronic systems for controlling the whereabouts of animals have generally been one of two basic types which may be referred to as the "wire loop" type and the "remote broadcast" type, respectively.
Various wire loop systems for controlling the whereabouts of animals are exemplified by U.S. Pat. No. 3,753,421 to Peck; U.S. Pat. No. 4,136,338 to Antenore; U.S. Pat. No. 4,733,633 to Yarnall, Sr. et al.; U.S. Pat. No. 4,745,882 to Yarnall, Sr. et al.; U.S. Pat. No. 4,766,847 to Venczel et and U.S. Pat. No. 4,967,695 to Giunta. In such systems, one or more continuous wire loops are routed along an arbitrary path to define a boundary. In some cases the wires are run above ground, in others they are buried. A low level electrical current signal is passed through the loop using a controller connected directly to the loop. The controller itself is typically mounted at an indoor location for protection from the elements as well as for access to an A.C. line from which it derives power. This location can be some distance from the desired boundary. In that case, the wire loop is typically twisted over that portion of its run lying between the controller and the closest point on the boundary.
In operation, the untwisted portions of the wire loop emit a relatively weak electrical field which can be sensed by a battery-powered unit affixed to the animal by suitable means such as by attachment to a collar worn by the animal. When the animal approaches the wire, the unit senses the field and initiates the application of at least one aversive stimulus to the animal. Since the currents in any twisted portions of the wires flow in opposing directions, their fields cancel sufficiently that the unit affixed to the animal does not initiate application of an aversive stimulus even when the animal is near by. Thus, by twisting portions of the loop together, a boundary located remotely from the controller and/or one having two or more distinct portions lying physically separated from one another can be formed using a single loop of wire connected to a single controller.
Some prior art animal whereabouts control systems include an animal-carried stimulator device which are responsive to sensed variations in signal strength as indicating the relative distance of the animal from the boundary. In certain of them, the animal's approach to the wire, as indicated by a received signal strength above a predetermined threshold, initiates application of a first and relatively mild aversive stimulus such as generation of a tone which terminates if the animal retreats from the boundary. If on the other hand, the animal moves closer yet toward the loop, a higher threshold of signal strength is exceeded and a stronger aversive stimulus such as an electric shock is administered in order to repel the animal from the boundary as defined by the location of the wire. While wire-loop type systems have been popular, they too suffer from a number of significant problems.
One problem is that interruption of A.C. power or failure of the controller renders the entire system inoperable. The wiring installation requirements for wire-loop type systems are also a disadvantage. As noted above, a continuous length of wire must be run from the controller, around the desired boundary and back to the controller which is usually located at an indoor location remote from any point on the desired boundary. The wire must be installed around or through any intervening walls or other obstacles. Even with special equipment built for the purpose, it is not a trivial task to bury a wire loop encompassing the perimeter of a large property. In order to cross existing sidewalks, driveways, or other concrete or masonry structures, it may also be necessary to cut through the concrete to provide a channel through which the wiring may be passed. Patches formed over such channels can be unsightly and, if not properly installed, can form areas subject to water infiltration and cracking. In the event the wire loop breaks, the break must be located, excavated and repaired. Until such repair is effected, the entire boundary is disabled, not merely the portion of it in the vicinity of the break in the wire. With buried wire loop systems, reconfiguring the size, shape and/or location of the boundary involves excavating the wire loop and reburying it in a new location or abandoning the existing loop and burying a new one.
Due to the need to twist the loop wires together at locations through which the wires must pass but where no boundary is desired, wire loop systems tend to be difficult to install. This is particularly true in cases where one desires to define boundaries having configurations other than a closed perimeter boundary encompassing an area within which an animal is free to roam. Examples include perimeter boundaries including intentional gaps defining passageways and boundaries including several mutually separated small areas or zones from which the animal is to be excluded.
In order to eliminate the need for boundary wiring, remote broadcast systems for controlling the whereabouts of animals have been proposed. Remote broadcast systems are those in which a perimeter boundary is established by broadcasting a signal from a central location toward an intended outer perimeter boundary. The location of the boundary is defined based on the strength of that broadcast signal as sensed by a unit affixed to the animal. For example, U.S. Pat. No. 5,067,441 to Weinstein describes an animal restraining system including a radio frequency transmitter, a transmitting antenna located inside an area in which the animal is to be restrained and a collar unit worn by the animal. A coaxial cable is run between the transmitter unit and the transmitting antenna. When the animal strays from the transmitting antenna a distance sufficient to permit the signal strength received by the collar unit to fall below a predetermined level, a first aversive of stimulus, such as a beeping tone, is generated. If the animal strays further from the antenna by a distance sufficient to cause the signal strength to fall below a second predetermined threshold, a stronger stimulus such as a shock is administered to the animal to deter its departure from the area. A similar system is described in U.S. Pat. No. 4,898,120 to Brose.
A fundamental shortcoming of remote broadcast type systems for controlling animal whereabouts is that the collar unit worn by the animal does not detect proximity of the animal to a structure whose physical location reliably indicates the location of the intended boundary. Instead, such systems rely on measuring signal strength as an indicator of the distance the animal from a transmitting antenna which may be located a considerable distance from the boundary. Consequently, that indication is not always reliable since the strength of the received signal can change due to constructive and destructive interference generated by signal reflections, shadowing by metallic objects and other uncontrollable variations in local reception conditions. Since local reception conditions can fluctuate, the size, shape and location of the boundary locii at which stimuli will be administered can also fluctuate. For example, if the signal path between the transmitting antenna is temporarily altered by an automobile which pulls into one's driveway, the animal may receive a shock even if the animal remains within an intended perimeter boundary.
Remote broadcast systems are also limited with respect to the sizes and shapes of perimeter boundaries they can define. While generally circular boundaries or ones conforming to the radiation pattern of a particular antenna can be implemented, continuous perimeter boundaries encompassing jutting regions or other well defined irregularities would be extremely difficult, if not impossible to establish using a remote broadcast type system. Another limitation of such systems is that because signal strength values are not unique to individual locations within the field of the transmitter, they are not well suited for excluding an animal only from arbitrarily located distinct positions, such as the site of one's prized rose bush for example. While wire loop systems offer greater flexibility as to boundary shape, they are subject to the problems and limitations described above.
Another limitation of prior art systems is that they are only capable of defining boundaries whose positions remain essentially fixed. There is a need for an animal whereabouts control system which, while suitable of defining fixed boundaries, is also capable of defining boundaries which move with a mobile agent such as a child or another animal so that a particular animal such as a dog can be kept separated from child or other animal while otherwise allowing both dog and child complete freedom of movement.
Prior art systems for controlling the whereabouts of animals also deliver stimuli of substantially invariant intensity. While some systems, such as those described in U.S. Pat. No. 4,898,120 to Brose deliver stimuli whose intensity increases as the animal moves closer to the boundary, small or timid animals are nonetheless administered aversive stimuli of substantially the same intensity as larger or more aggressive animals. At least one system, the PET ALERT buried wire system available from Futuretech, Inc. of Columbus, Ohio, is professedly capable of adjusting stimulus intensity by way of a multiple position switch located at the central control unit. However, in situations where the whereabouts of more than one animal are to be controlled rising a single system, such systems lack the capability permitting a user to independently adjust the intensity of the aversive stimulus to be delivered to each individual animal according to its individual temperament and/or physical characteristics.
As noted above, electronic systems for controlling the whereabouts of an animal typically employ a battery-powered unit affixed to the animal for sensing the boundary and administering a desired stimulus. While battery life of several months is presently achievable using state of the art batteries, achieving even longer operation of such system with state of the art batteries or achieving comparable operating life with less expensive batteries is desired. | {
"pile_set_name": "USPTO Backgrounds"
} |
In the field of plastic surgery, it is often desirable to document a patient's appearance before and after surgery. Photography is the usual means of documentation. However, often a photograph from one angle or even several angles is not sufficient to show the true transformation. Accordingly, a need exists for a system that documents up to a full 360° view of a patient before and after surgery. | {
"pile_set_name": "USPTO Backgrounds"
} |
The field of the invention is that of blending dispensers for liquids. More particularly, the field is that of blending dispensers capable of dispensing a variety of blending mixes.
In liquid dispensing devices, for example gasoline fuel pumps, different grades of gasolines are conventionally mixed to provide a specific blend. Using two gasoline sources, one supply tank containing gasoline having a first octane rating, for instance, 95, and the other supply tank containing gasoline having another octane rating, for instance, 83, a dispenser can produce gasoline blends having a desired octane rating in the range of 83 to 95. The following example uses 83 and 95 octane gasolines as the component fuels because they represent a common prior art range of octanes; however, a variety of ranges of octanes have been used to mix and provide blends of gasoline. For example, gasolines of various octane ratings can be provided by mixing component gasolines in the following percentages:
______________________________________ Octane % of 83 octane % of 95 octane ______________________________________ 83 100 0 87 67 33 89 50 50 91 33 67 95 0 100 ______________________________________
It is imperative in such blending dispensers that the component fuels are accurately dispensed to provide the desired blend ratio.
In prior art systems, a proportional control system has been used to check the blending ratio periodically by observing the instantaneous flow rates of the two component streams of fluid (e.g. from the 83 and 95 octane tanks). An electronic controller observes the instantaneous flow rates by receiving signals from pressure sensors coupled to the two flow lines. When the instantaneous flow rates substantially deviate from those needed to provide the desired mixture, the valves which control the component streams are adjusted accordingly. This results in a dispenser which tends to deliver an instantaneous blend ratio equal to the desired mixture only after a significant portion of the desired quantity of fuel has been dispensed, assuming that liquid pressure remains relatively constant. Thus a significant quantity of the dispensed fuel may have an incorrect blend or mixture. However, such proportional control systems only correct for errors in the instantaneous flow rate and do not account for the total errors in fuel which has already been dispensed so that the total amount of dispensed fuel will be a desired blend.
Consider a hypothetical system having 83 octane and 95 octane gasoline which uses a proportional control system to provide a range of gasolines having different cumulative blend ratios (i.e., the amount of 83 octane dispensed divided by the sum of the amount of 83 and 95 octane dispensed). Initially, relatively little of the 83 octane is dispensed compared to the amount of 95 octane dispensed. After periodic checking and correcting of the instantaneous blend ratio, the cumulative blend ratio curve steadies as the dispenser eventually provides an instantaneous blend of approximately 50% of 83 octane fuel and 50% of 95 octane fuel. However, the initial disparity does not enter into the calculation of the instantaneous rates, so that the total quantity of dispensed fuel for the session contains less than the desired 50% of 83 octane fuel. Accounting for the total blend ratio, a steady state error exists created by the initial mixture which contained substantially more 95 octane fuel than 83 octane fuel. The steady state error represents that amount of 95 octane gasoline which exceeds the amount of 83 octane gasoline, and the error can never be eliminated because the instantaneous rates are maintained at the 50% ratio. The cumulative blend ratio does approach the desired cumulative ratio as the amount of fuel dispensed approaches infinity, but the average consumer does not dispense such a large volume of fuel, rather the typical volume of gasoline dispensed by a consumer is between five and ten gallons. Thus, as a practical matter, the steady state error does not substantially decrease for gasoline dispensing applications because of the low volume of dispensing. Additionally, small quantities of dispensed fuel tend to have large errors. Also, random fluctuations of pressure within the proportional control system can add to the steady state error.
For example, assume that an operator or customer desired to put 10 gallons of 89 octane gasoline into the automobile fuel tank. Initially, for some reason, the 95 octane gasoline flowed at a rate four times that of the 83 octane gasoline. After the first gallon, the dispenser had provided 0.2 gallons of 83 octane gasoline and 0.8 gallons of 95 octane gasoline. At the one gallon mark, the dispenser corrected the difference in flow rates, and the remainder of the ten gallons were dispensed in an approximately 50% blend ratio. Thus at the end of the dispensing cycle, the dispenser provided 5.3 gallons of 95 octane gasoline compared to 4.7 gallons of 83 octane gasoline, resulting in a cumulative blend ratio of 4.7/(4.7+5.3) or 47%.
In the same example, assume that immediately after five gallons had been dispensed, the pressure in the 83 octane gasoline line fell dramatically so that only 0.3 gallons were dispensed while 0.7 gallons of 95 octane gas were dispensed. After that dramatic pressure drop, the system then corrected for the pressure differential and dispensed an approximately 50% blend ratio. Thus, at the end of this dispensing, the dispenser provided 5.5 gallons of 95 octane gasoline compared to 4.5 gallons of 83 octane gasoline, resulting in a cumulative blend ratio of 4.5/(4.5+5.5) or 45%.
One form of prior art dispenser uses fixed orifice valves with pressure equalizers to achieve proper blending, generally having a cumulative accuracy of approximately 3%. The size of the orifice for each gasoline determines the instantaneous blend because the pressures are maintained relatively equal by pressure equalizers. However, to provide a blend which does not correspond to specific orifice sizes requires that the valves of the dispenser must be periodically turned on and off. Because the pressure sensors, valves, and pressure equalizers of dispensers are least accurate during starting and stopping, using fixed orifice blenders limits the versatility of the blending dispensers.
In dispensing operations having more than one dispenser for each pair of tanks, which is the usual circumstance, pressure equalizers often cannot perform adequately because of the variable pressures from the supplying tanks. For example, if three dispensers are currently dispensing 95 octane gasoline, and then a fourth dispenser is set to provide 89 octane gasoline, the fluid pressure in the supply line from the 95 octane supply tank should be substantially less than the pressure from the 83 octane supply tank. The resulting imbalance between pressures causes imprecision in accurately providing the desired cumulative blend.
Also, those dispensers tabulate the total amount dispensed, not the individual amounts dispensed from each tank. This can present difficulty to sellers of gasoline who must accurately measure the amount of gasoline withdrawn from each supply tank. Although an estimate of the individual amounts withdrawn are made from the total amount dispensed, additional proving must occur to verify the estimated amounts. Further, to insure that the desired cumulative blend is produced so the octane rating is at least as high as desired, the dispenser is biased in favor of dispensing more of the higher octane, more expensive gasoline.
Another feature of gasoline dispensers is that the operator may choose to dispense the gasoline quickly or slowly by actuating the nozzle handle. Thus, the operator can control the nozzle of the dispenser to change the flow rate or turn the flow on or off at any time. Due to the unpredictability of the operation of the nozzle, the signals sent by the pressure sensors may differ greatly at different times. When the nozzle is off, no flow exists, and the periodic signals sent by the pressure sensors may not present adequate information to make an accurate blend calculation. Thus, prior art dispensers have further problems due to erratic and unpredictable use which further impairs their accuracy.
Thus, a need exists for an improved blending dispenser that avoids the above-mentioned problems and accurately provides a desired cumulative blend. Also needed is a dispenser which separately measures the volume of the component fluids mixed and dispensed. A further need exists for a blending dispenser which adjusts component fluid flows according to the total cumulative volume of flow rather than instantaneous flow rates. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention generally relates to a calibration system for recalibrating electronic thermometers. More specifically, the present invention relates to recalibration system comprising a tympanic thermometer, a blackbody calibration unit and a computer for recalibrating the infrared temperature sensor within the tympanic thermometer. In particular, the present invention relates to a recalibration system for recalibrating tympanic thermometers using the ambient temperature sensed by the tympanic thermometer as a primary control parameter in the recalibration process.
2. Background Art
The diagnosis and treatment of many body ailments depends upon an accurate reading of the internal or core temperature of a patient's body temperature reading, and in some instances, upon comparison to a previous body temperature. For many years, the most common way of taking a patient's temperature involved utilization of Mercury thermometers. However, such thermometers are susceptible to breaking and must be inserted and maintained in the rectum or mouth for several minutes, often causing discomfort to the patient.
Because of the drawbacks of conventional Mercury thermometers, electronic thermometers were developed and are now in widespread use. Although electronic thermometers provide relatively more accurate temperature readings than Mercury thermometers, they nevertheless share may of the same drawbacks. For example, even though electronic thermometers provide faster readings, a half a minute must still pass before an accurate reading can be taken. Finally, electronic thermometers must still be inserted into the patient's mouth, rectum or axilla.
Tympanic thermometers provide nearly instantaneous and accurate readings of core temperature without undue delay attendant with other thermometers. The tympanic thermometer is generally considered by the medical community to be superior to oral, rectal or axillary sites for taking a patient's temperature. This is because the tympanic membrane is more representative of the body's internal or core temperature and more responsive to changes in core temperature. Tympanic thermometers, those thermometers that sense the infrared emissions from the tympanic membrane, offer significant advantages over Mercury or conventional electronic thermometers.
Recent efforts to provide a method and apparatus for measuring temperature of the tympanic membrane have produced several excellent infrared tympanic thermometers. For example, U.S. Pat. No. 5,293,877 to O'Hara et al. provides for a tympanic thermometer that measures internal body temperature utilizing the infrared emissions from the tympanic membrane of the ear, and is herein incorporated by reference in its entirety. Typically, tympanic thermometers require calibration at the factory during manufacturing in order achieve the quick and accurate temperature reading capability noted above. Calibration of the tympanic thermometer at the factory requires individual calibration of each thermometer unit so that the proper calibration parameters can be written to the EEPROM of each thermometer's microprocessor. These calibration parameters involve determining the proper values for variables representing the sensors within each thermometer. Once these calibration parameters are determined and written to the memory of each thermometer, calibration is complete and the unit is shipped for sale.
However, responsivity of the infrared system and transmissivity of the optical system set during calibration can change over time, thereby bringing the tympanic thermometer out of calibration which results in inaccurate temperature readings being taken by the thermometer. Responsivity of the tympanic thermometer's infrared system involves changes in the response characteristics of the thermal radiation sensor of the thermometer over time. Similarly, transmissivity of the optical system deals with the transmission characteristics of the optical waveguide and other parts of the thermometer's optical system that may drift or change as a function of time or due to scratches and deformations that occur during use. During recalibration, the calibration parameters dealing with the thermometer's infrared and optical systems are adjusted.
Recalibration of the tympanic thermometer usually requires recalibrating the variables related to the infrared and optical subsystems of the thermometer incorporated in the calibration equations written to the EEPROM during factory calibration. A prior art recalibration device usually comprises a unit housing one or more blackbodies that permit the user to recalibrate the thermometer at one or more set temperatures designated for each blackbody. In operation, the sensor portion of the thermometer is inserted into a cavity containing a blackbody set at a predetermined temperature. Readings are then taken from each sensor and a set of calibration parameters are calculated and written over the original parameters set in the EEPROM.
Ambient temperature is another important calibration parameter that must be determined during the recalibration procedure because it provides an indication of temperature stability of the surrounding environment that the tympanic thermometer is experiencing prior to recalibration. Temperature stability permits accurate recalibration to take place as long as recalibration is within a specific range of ambient temperature conditions. For example, a tympanic thermometer experiencing an ambient temperature that is too high or otherwise outside the permissible range of ambient temperatures will adversely affect the recalibration process and result in an inaccurate calibration of the thermometer.
To sense the ambient conditions being experienced by the tympanic thermometer, prior art recalibration devices have utilized an ambient sensor that resides directly on the recalibration device itself for sensing the surrounding ambient temperature prior to recalibration. Although this method provides an easy means of determining ambient temperature, several disadvantages remain. For example, a more accurate ambient temperature reading of the tympanic thermometer is best taken from the thermometer itself rather than from the recalibration device since temperature stability of the tympanic thermometer is a far more critical factor than the temperature stability of the room containing the recalibration device. Further, instances may occur where a tympanic thermometer to be recalibrated might have just been stored in a high temperature area, such as a the compartment of a vehicle exposed to the sun or in a room having different environmental conditions than the room where recalibration is occurring. In this instance, the ambient temperature of the tympanic thermometer will be much higher than the surrounding cooler temperature of the room sensed by the calibration device's ambient sensor, thereby providing an inaccurate ambient temperature reading to the recalibration device since the thermometer has not stabilized to its surroundings. However, if the recalibration system takes into account the present ambient temperature experienced by the tympanic thermometer itself prior to recalibration, then a more accurate and reliable determination of the thermometer's temperature stability can be determined before recalibration occurs.
As of yet, nothing in the prior art has addressed the problem of developing an ambient sensor system that determines the temperature stability of the tympanic thermometer before recalibration of the thermometer occurs. Further, nothing in the prior art has addressed the problem of ensuring that recalibration takes place in an environment where ambient temperature is within a stable range of temperatures.
Therefore, there exists a need in the medical art for an ambient sensor system that takes an ambient temperature reading from within the thermometer itself without use of separate ambient sensors outside the thermometer and also incorporates a fail-safe routine whereby recalibration does not occur unless the ambient temperature of the thermometer is within a predetermined range and the thermometer is in a state of thermal equilibrium. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to a semiconductor device comprising bumps that are suitable for mounting on a circuit board with an anisotropic conductive film therebetween.
Recently, a semiconductor device for surface mounting comprising bumps (projecting terminals) capable of electrically and mechanically connecting to a circuit board has been often used.
The structure of the bump in such a conventional semiconductor device and a fabricating method thereof will be briefly described with reference to FIG. 14A to FIG. 14D. Incidentally, these drawings are sectional views, but oblique lines showing sections are omitted.
FIG. 14D shows a section of the bump and thereabout of a complete semiconductor device.
On the surface of a silicon wafer 213 which is cut into semiconductor chips, a selective oxide (LOCOS) film 204 which is a layer necessary for fabricating a semiconductor device is provided, and an aluminum layer 702 is provided on the selective oxide (LOCOS) film 204. This aluminum layer 702 is a layer necessary to input and output a power supply or a signal to/from interconnections in the semiconductor device and an integrated circuit from/to the outside.
On top of that, a passivation film 703 which is an insulation protection film covering the entire face of the silicon wafer 213 is provided, and an opening portion 703a is formed in the passivation film 703 on the aluminum layer 702. A gold bump 701 which is mushroom shaped is provided from the aluminum layer 702 within the opening portion 703a extending onto the passivation film 703 around the opening portion 703a with a noble metal film 705 therebetween.
In this drawing, only one bump is shown, but many bumps are provided in a real semiconductor chip.
FIG. 14A to FIG. 14C are views showing the mid-steps of the fabrication of this semiconductor device.
As shown in FIG. 14A, the selective oxide film 204 is formed on the silicon wafer 213, and the aluminum layer 702 which is connected to the internal integrated circuit is formed at a necessary position on the selective oxide film 204. The passivation film 703 which covers the entire face of the silicon wafer 213 including the aluminum layer 702 is formed, and the opening portion 703a for establishing connection with the outside is formed on the aluminum layer 702.
Then, as shown in FIG. 14B, the noble metal film 705 is formed on the entire faces of the passivation film 703 and the aluminum layer 702, and further a photosensitive resist 710 is selectively (except for a bump formation region) formed on the noble metal film 705.
The noble metal film 705 is a noble metal layer such as an alloy of titanium and tungsten, or the like and has a function as an electrode for producing the gold bump 701, which is formed on the aluminum layer 702 in a subsequent step, by electro-plating, and another function of improving the connection between the aluminum layer 702 and the gold bump 701.
This noble metal film 705 is formed by being laminated on the entire surface in a vacuum apparatus.
Next, as shown in FIG. 14C, a gold layer is produced in a portion in which the resist 710 is not formed by the electro-plating step to form the gold bump 701 which is the mushroom shaped bump electrode.
Then, after the resist 710 is removed, the noble metal layer 705 is removed with the gold bump 701 as a mask with only a portion thereof under the gold bump 701 left. FIG. 14D is a sectional view of this state.
Through such process steps, the bump electrodes of the gold bumps 701 are formed on the silicon wafer 213, and the silicon wafer 213 is cut into discrete semiconductor chips to complete semiconductor devices.
However, in the semiconductor device comprising such conventional bumps, since a plating process which is hard to manage is employed for making up the bumps, the bumps are prone to be nonuniform in height, and additionally, the use of costly gold for the material of the bumps results in a high cost of production.
The present invention is made to solve such problems and its object is to make it possible to easily fabricate bump electrodes of a semiconductor device at low cost and to make the height of the bumps uniform.
Moreover, another object is to make it possible that the height of a most projecting end face of the bump is sufficiently higher than those of projecting faces of any other parts of the semiconductor device in order that the bump can be surely electrically connected to an interconnection on a circuit board when such a semiconductor device is mounted on the circuit board with an anisotropic conductive film therebetween, and that an effective area of the end face is made large to catch a plurality of conductive particles.
To achieve the above object of the present invention, a semiconductor device comprising a polysilicon layer used for an interconnection and a gate of a transistor, an insulation layer covering thie polysilicon layer, an interconnection conductor layer formed on the insulation layer, and a bump for inputting and outputting a power supply or a signal to an integrated circuit, on the surface of a semiconductor chip in which the integrated circuit is formed, is structured as follows.
A polysilicon film and an insulation film made of the same materials as those of said polysilicon layer and said insulation layer are provided at a region at which the bump is formed, on the surface of the semiconductor chip; a first conductor which covers the insulation film and is electrically connected to the interconnection conductor layer is made of the same material as that of the interconnection conductor layer by sputtering; a protection insulation film which covers the surfaces of the first conductor, the interconnection conductor layer, and the semiconductor chip and in which an opening portion is provided on the first conductor is formed; a second conductor which conducts to the first conductor through the opening portion is formed on the protection insulation film by sputtering.
Further, the bump is composed of the polysilicon film, the insulation film, the first conductor, and the second conductor, and is formed so that a height of a most projecting end face thereof from the surface of the semiconductor chip is higher than those of projecting faces of any other parts.
Also in this case, each of the aforesaid first conductor and the second conductor can be made of aluminum.
Moreover, it is preferable that the most projecting end face of the bump is covered with a conductive film for preventing surface oxidation, that is, a conductive oxidation film or a noble metal film.
In the case where the aforesaid bump is composed of the aforesaid first conductor and the second conductor which conducts to the first conductor through the opening portion formed in the protection insulation film covering the first conductor, the film thickness of the protection insulation film at the region under the second conductor is formed thicker than that of the other region, thereby increasing the bump""s height.
Further, in the present invention, a semiconductor device comprising a bump, on the surface of a semiconductor chip in which an integrated circuit is formed, for inputting and outputting a power supply or a signal to the integrated circuit and mounted on a substrate with an anisotropic conductive film containing a large number of conductive particles therebetween is structured as follows.
On the surface of the semiconductor chip, a first conductor which is electrically connected to the integrated circuit; a protection insulation film which covers the surfaces of the first conductor and the semiconductor chip and in which a through hole is formed on the first conductor; and a second conductor which is formed on the protection insulation film by sputtering and conducts to the first conductor through the through hole, are provided, wherein the bump is composed of the first conductor and the second conductor, and is formed so that a height of a most projecting end face thereof from the surface of the semiconductor chip is higher than those of projecting faces of any other parts by an error in diameter of the large number of conductive particles contained in the anisotropic conductive film or more.
It is desirable that a maximum opening dimension of the through hole formed in the protection insulation film is within 1.5 times a minimum diameter of the large number of conductive particles contained in the anisotropic conductive film.
Moreover, it is acceptable that the through hole formed in the protection insulation film is composed in shape of a square, a rectangle, a polygon, a circle, or an ellipse, or a plurality of through holes in these different shapes.
The second conductor is formed in an area larger than a region within which a step is formed at the protection insulation film caused by a step of the first conductor, thereby increasing an effective area of the most projecting end face of the bump. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to solutions of separately-prepared oligo-urethane ethers containing terminal OH-groups in relatively high molecular weight polyethers containing terminal hydroxyl groups and to the use of these solutions as modified polyols in the production of polyurethane foams characterized by excellent high-frequency weldability and flame-laminatability.
Applications where high-frequency weldability is a particularly desirable property include, for example, the production of door linings for motor vehicles, in which sheets of foam have to be welded to one another or to other materials; the manufacture of articles with quilted surface appearances; or the production of moldings. In addition, flame lamination is used for the production of composite systems of foams with textiles, such as in upholstery backings which are subsequently profiled and/or formed by high-frequency (e.g. where the welding energy is provided by an electromagnetic field). (HF welding).
It is known that flame-laminatable and, to a certain extent, high-frequency-weldable foams can be produced from polyisocyanates and polyester polyols using suitable auxiliaries and additives. However, these foams can only be produced in special processing machines and are inferior in many properties to polyether-polyurethane foams. For example, their open-cell structure is poorer, their elasticity lower and their resistance to moisture and heat inferior.
Flame-laminatable and high-frequency-weldable polyurethane foams can be produced from polyether polyols, polyisocyanates, water and/or blowing agents in the presence of emulsifiers, stabilizers, catalysts and other auxiliaries, by the addition of special auxiliaries.
Thus, U.S. Pat. No. 3,205,120 describes the production of flame-laminatable polyether-polyurethane foams by the addition of a relatively small quantity of a polyol (particularly phosphorous-containing polyols, such as tris-(dipropylene glycol)-phosphite) having a molecular weight in the range from 200 to 1500. Disadvantages of this process include a deterioration in processing reliability, a certain tendency towards core-discoloration and a flame-lamination behavior which is distinctly inferior to that of a polyester-polyurethane foam because of the polyol quantities normally used.
U.S. Pat. No. 4,060,439 describes the cofoaming of small quantities of alkylene glycols containing from 2 to 8 carbon atoms, or triols containing from 3 to 10 carbon atoms, dialkanolamines containing from 2 to 10 carbon atoms with short-chain glycol ethers and polyhydric phenols into flexible polyether foam formulations. However, experience has shown that the co-foaming of compounds such as these makes foaming more difficult and, in particular, very considerably narrows the processing gap between an open-cell and a closed-cell structure.
In addition, U.S. Pat. No. 3,497,416 describes the foaming of a polyether polyol with a modified polyisocyanate (the reaction product of dipropylene glycol and/or dibutylene glycol with an excess of polyisocyanate) for the production of a weldable polyurethane foam. The disadvantage of this process lies in the fact that, to obtain sufficient open cells, dimethyl formamide --a toxicologically-unacceptable substance, has to be used as cell-opening agent. In addition, foams of this type have a high compression set, and polyether-NCO-prepolymers of this type used show only moderate stability in storage.
In view of the disadvantages of polyether-polyurethane foams which account for the fact that, on the whole, polyester-polyurethane foams are used for flame lamination and for high-frequency welding, there is a considerable need for a flame-laminatable and high-frequency (HF)-weldable polyether foam which can be manufactured safely.
Solutions of polyisocyanate-polyaddition compounds in polyols are also known. Thus, German Offenlegungsschrift No. 2,638,759 describes solutions of this type having solids contents of from 5 to 70%, by weight, which are obtained by either reacting diisocyanates with H-active compounds (including, among many others, diprimary diols) in polyhydric alcohols having a molecular weight of from 62 to 450 (but generally, from 62 to around 200) as reaction medium or by subsequently dissolving the powdered, separately-produced polyaddition compounds in the polyhydric alcohols.
Although solutions of this type may frequently be used as starting materials in the production of polyurethane plastics, they are not suitable for the production of flexible coatings and, in particular, flexible foams. The introduction of significant amounts of the polyaddition compound into the polyurethane foam formulation is only possible if relatively large quantities of the low molecular weight polyhydric alcohols (the solvents) are used at the same time. This seriously affects processing reliability in the manufacture of flexible foams (effecting the critical links between open-cell structure and shrinkage properties) or it makes the production of an open-cell flexible foam completely impossible.
It has now suprisingly been found that oligourethane ethers containing terminal OH-groups of diisocyanates and dihydric, relatively short-chain polyether diols form clear, stable solutions in relatively high molecular weight, polyhydric polyether polyols optionally at elevated temperature- and that solutions of this type may readily be processed into flexible foams characterized by good mechanical properties and by good high-frequency weldability. | {
"pile_set_name": "USPTO Backgrounds"
} |
Flexible graphite sheet material can be obtained by first intercalating graphite with an intercalating agent to form a graphite intercalation compound that is then exposed to a thermal shock, for example, at a temperature of 700° C.-1,050° C. for a short duration of time (20-60 seconds) to expand or exfoliate the graphite. The exfoliated graphite particles are vermiform in appearance, and are commonly referred to as “worms”. The worm is essentially a network of interconnected, thin graphite flakes, with pores present between flakes that make the worms compressible. The worms can be re-compressed together into flexible sheets (foils or films), referred to as “flexible graphite” or “exfoliated graphite sheet” or “graphite sheet” that can be wound up on a drum to form a roll. U.S. Pat. No. 3,404,061 describes the preparation of flexible graphite from expanded or exfoliated graphite particles.
Most of the graphite flakes in flexible graphite are oriented parallel to the two opposed major exterior surfaces. Although flexible graphite is typically highly electrically conductive (typically around 1,300 S/cm) in the in-plane directions, flexible graphite's through-plane electrical conductivity is significantly less (often only about 15 S/cm). The anisotropy ratio, the ratio of highest electrical conductivity to lowest conductivity values, is typically as high as 86:1 (and often higher than this value). The thermal properties of flexible conventional flexible graphite are similarly highly anisotropic with the in-plane thermal conductivity being many times greater than the through-plane conductivity.
The properties of flexible graphite (such as its density, flexibility and its electrical and thermal conductivity) can be adjusted by incorporating a resin during forming of the material or impregnating it with a resin or another suitable impregnation medium after it is formed. The impregnation medium at least partially fills the pores between the graphite flakes. Resins suitable for impregnation of flexible graphite include phenolic, furan, epoxy and acrylic resins.
During compression or embossing processes, air can become trapped within the flexible graphite as it is compressed. This can cause problems including blistering and/or delamination of the embossed material. This is particularly undesirable for some end-use applications. For example, blistering or delamination in flexible graphite materials can weaken the material and make it more permeable to fluids. The material is also rendered less homogeneous as a result and can exhibit undesirable localized differences in thermal and electrical conductivity. The foregoing problems can be difficult to detect during fabrication and may only surface at a later date. Finally, in applications where the material is subsequently impregnated with a resin, delamination and/or blistering can result in voids in the plate material that become filled with resin. Where the resin employed is electrically nonconductive, this can result in undesirable nonconductive regions within the material.
For thermal management applications, such as heat sinks, heat spreaders and thermal interfaces, flexible graphite offers many advantages over other materials that are commonly used in these applications such as copper, steel and aluminum. For example, relative to these metals, flexible graphite is often lighter, less susceptible to corrosion, has lower thermal expansion and has higher thermal conductivity in the in-plane direction.
The present application relates to methods and apparatuses for processing of flexible graphite that can be used to modify or enhance its properties, in particular for use in thermal management applications. | {
"pile_set_name": "USPTO Backgrounds"
} |
Handheld devices, such as personal digital assistants (PDA) and mobile phones, are now being equipped with hardware and software to handle several different computing tasks. Handheld devices are being equipped with communications adapters to allow the handheld devices to access the Internet, other handheld devices, and other information handling systems. Handheld devices are also being used to process multimedia data, such as audio and video data. Many handheld devices are capable of playing video on an integrated screen. Handheld devices are being integrated with more components to handle the increased functionality. However, as more components are integrated with the handheld devices and as processing increases, the handheld devices draw more power.
Power is limited on most handheld devices. Most desktop computers take power from a power supply connected to an alternating current (AC) power outlet and generally don't need to worry about conserving power. Handheld devices generally take their power from standard power cells. Handheld devices are designed to be small and light to make them portable for consumers. The power cells are generally selected to be small and light to not hinder the handheld device. However, the increased processing performed to handle new functionality, such as communications or multimedia playback, takes more power from the handheld devices than general processing tasks the handheld devices were originally used for.
Current methods of reducing power consumption are not adequate. To conserve power, a handheld device may reduce the speed at which its central processing unit (CPU) is run. However, inhibiting the CPU reduces the performance of the handheld device in most or all of the functions of the handheld device. Alternatively, specific functions or hardware components within the handheld device may be completely disabled to conserve power. However, completely disabling functions within the handheld device reduces a stability expected by a user. Power-saving modes can be enabled through software by having a software application decide processing can be reduced. However, such applications are not generally aware of the effect of running in a reduced power mode on other components within the device. The application may not be aware of all the processes running within the device. From the above discussion, it is apparent that an improved method of conserving power within a system would be useful. | {
"pile_set_name": "USPTO Backgrounds"
} |
Arrows for use with archery bows are of course well known in the art and have been refined over the years to meet the special needs of the various types of archers such as hunters, target shooters and flight shooters. Modern day arrows typically comprise a tubular aluminum shaft (though wood and fiberglass are still in use), turkey feather fletching at the trailing end of the arrow, a steel or bronze point, and a plastic nock for engaging the bow string. All components of the modern arrow have been carefully engineered and reengineered for optimum performance.
Notwithstanding the relatively advanced technology of arrow design, present day arrows still have certain drawbacks when used in combination with conventional bows. One particular concern is the distance traveled or flight of an arrow when shot from a bow of standard construction . In this regard, at distances greater than about 25 yards, conventional arrows do not follow a level line of flight and hence, the archer must compensate for vertical drop of the arrow by aiming above his intended point of impact. Though sophisticated sighting equipment is available to aid the archer in judging the angle at which the arrow should be released in order to hit an intended target at a distance further than 25 yards, such devices are not totally accurate and they often require that the archer, particularly in the case of bow hunters, make a judgement as to target distance. Thus, the archer's accuracy at such long range target distance is significantly reduced. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a film formation apparatus and a film formation method, which are used when a film formation material is purified by sublimation to form a film using the purified material in forming an EL element over a substrate.
2. Description of the Related Art
In recent years, there has been an active study of a light emitting device which has an EL element as a self light emitting element, and in particular, a light emitting device using an organic material as an EL material has attracted attention. This light emitting device is also called an organic EL display (OELD) or an organic light emitting diode (OLED).
Note that the EL element has a layer containing an organic compound in which electro luminescence is generated by applying electric field (hereinafter referred to as EL layer), an anode, and a cathode. The electro luminescence in the organic compound includes luminescence produced in returning from a singlet excitation state to a ground state (fluorescence) and luminescence produced in returning from a triplet excitation state to a ground state (phosphorescence). A light emitting device manufactured by a film formation apparatus and a film formation method according to the present invention can be applied to the case where either luminescence is used.
A light emitting device has a characteristic that a problem with respect to an angle of a field of view is not caused because it is a self light emitting type which is different from a liquid crystal display device. That is, it is more suitable than the liquid crystal display device when a display is used in the outdoors, and thus various ways of use are proposed.
The EL element has a structure in which an EL layer is interposed between a pair of electrodes. The EL layer generally has a laminate structure. Typically, there is a laminate structure called “hole transport layer/light emitting layer/electron transport layer”, which is proposed by Tang, et al. of Eastman Kodak Company. Light emitting efficiency is very high in this structure, and thus, this structure is adapted to most of the light emitting devices which have been researched and developed at present.
In addition, a structure in which a hole injection layer, a hole transport layer, a light emitting layer, and an electron transport layer are laminated in this order on the anode is preferable. Also, a structure in which a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are laminated in this order on the anode is preferable. The light emitting layer may be doped with a fluorescent pigment or the like. These layers may be formed using a low molecular system material or a polymer system material.
Note that all layers provided between the cathode and the anode in this specification is generically called the EL layer. Thus, the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, and the electron injection layer, which are described above, are all included in the EL layer.
Also, in this specification, a light emitting element formed of a cathode, an EL layer, and an anode is called the EL element. There are two types, that is, a type in which an EL layer is formed between two kinds of stripe-shaped electrodes provided to intersect each other (simple matrix type) and a type in which an EL layer is formed between a pixel electrode which is connected with a TFT and arranged in matrix and a counter electrode (active matrix type).
The most serious problem in putting the EL element to practical use is the insufficiency of the element life. Also, deterioration of the element is recognized in the form that a non light emitting region (dark spot) is expanded with light emission for a long period of time due to deterioration of the EL layer which eventually becomes a problem.
An EL material for forming the EL layer is deteriorated by an impurity such as oxygen, water, or the like. Also, when other impurity is included in the EL material, there arises a fear that the deterioration of the EL layer is adversely influenced.
Conventionally, when film formation is performed by an evaporation method, an evaporated material is used without being processed . However, it is considered that an impurity is mixed into the evaporated material at evaporation. That is, there is a possibility that oxygen, water, and other impurity are mixed as one reason for the deterioration of the EL element.
Also, when the evaporated material has been purified in advance, the purity can be increased. However, there is a possibility that an impurity is mixed during a period until the evaporation is completed. | {
"pile_set_name": "USPTO Backgrounds"
} |
Many therapeutic agents are highly effective for improving quality of life but, because of their abuse potential, may attract drug abusers. For example, opioids are excellent analgesic agents that can control severe and/or chronic pain, such as cancer pain and post-operative pain, but are also subject to abuse by drug users.
Opioids, also known as opioid agonists, are a group of drugs that exhibit opium- or morphine-like properties. Opioids are employed primarily as moderate to strong analgesic agents, but provide other pharmacological effects as well.
There have been previous attempts in the art to control the potential for abuse of opioid analgesics. For example, sustained release forms enable an active ingredient to work over many hours, and such slow release tends to deter illicit use of opioids because abusers tend to prefer the quick euphoric rush, also known as the “burst,” provided by immediate release opioids. Drug abusers, however, can defeat the controlled release design by crushing or dissolving the original drug form, for example a tablet, giving them access to snortable and/or injectable opioids that provide the burst. Accordingly, there is an important need for more effective methods of deterring opioid abuse while still keeping orally administered opioids available to patients who have a legitimate need for them.
Prior art approaches to this problem have involved combining an opioid with an opioid antagonist. When administered orally, these combinations provide the pharmacologic action of the opioid with minimal action of the antagonist. When administered parenterally, however, the antagonist can be-profoundly antagonistic to the opioid. Particular examples of such combinations include compositions comprising naloxone and morphine or oxymorphone (U.S. Pat. No. 3,493,657 to Lewenstein et al.); methadone and naloxone (U.S. Pat. No. 3,773,955 to Pachter et al.); methadol or acetyl methadol and naloxone (U.S. Pat. No. 3,966,940 to Pachter et al.); oxycodone and naloxone (U.S. Pat. No. 4,457,933 to Gordon et al.); and buprenorphine and naloxone (U.S. Pat. No. 4,582,835 to Lewis et al.). Also, the combination of pentazocine hydrochloride and naloxone has been marketed in the United States as TALWIN NX (Sanofi-Winthrop); VALORON N, a combination of tilidine and naloxone, has been available in Germany for the management of severe pain since 1978; and TEMGESIC NX, a combination of buprenorphine and naloxone, has been available in New Zealand since 1991.
U.S. Pat. No. 6,228,863 to Palermo et al. discloses an oral dosage form of an opioid agonist and an opioid antagonist that reduces the abuse potential of the opioid by combining the agonist and antagonist such that at least two steps are required to separate them.
U.S. Pat. No. 5,935,975 to Rose et al. discloses a method for treating drug dependency by the combined administration of the drug or an agonist of the drug and an antagonist of the drug.
There remains, however, a clear need in the art for more advanced oral dosage forms that are effective for preventing abuse and useful for delivering a therapeutic agent. | {
"pile_set_name": "USPTO Backgrounds"
} |
Many shingled roofs acquire leaks, which may damage their underlying structures. One cause of leaky roofs is improper installation of the roofs. For example, some roofing installers do not use adequate tar paper during installation of a shingled roof. This may result, as an example, in a roof that should last for thirty years only lasting five or ten years. Another installation problem may occur with flashing not being properly affixed or sealed.
Some shingled roofs can be repaired. For example, a second layer of shingles may be applied to a first layer of shingles. As with an original shingled roof, improper installation of the second layer of shingles may cause the roof to leak prematurely. In addition to the aforementioned problems, a repaired shingled roof may leak if the underlying substrate is defective. For example, if the substrate is plywood and has rotted, the repaired roof may leak prematurely.
When a shingled roof is improperly installed or repaired, any applicable warranties on the roofing shingles or other products may be voided by the manufacturers. For example, a roofing shingle manufacturer may warranty a roofing shingle for thirty years provided that it is installed properly. An installer may not properly install the roofing shingles and the roof may leak after ten years. Because of the improper installation, the roofing shingle manufacturer is not liable to replace the roof. The owner of the structure may turn to the installer for compensation. However, the installer may be out of business or not have the funds to cover the owner's losses. Accordingly, the owner is left without a remedy. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a system for using bridges in a failover system and, in preferred embodiments, for allowing two or more processors to act as bus masters in a PCI to PCI bridge failover system.
2. Description of the Related Art
The Peripheral Component Interconnect (PCI) bus is a high-performance expansion bus architecture that was designed to replace the traditional ISA (Industry Standard Architecture) bus. A processor bus master communicates with the PCI local bus and devices connected thereto via a PCI Bridge. This bridge provides a low latency path through which the processor may directly access PCI devices mapped anywhere in the memory or I/O address space. The bridge may optionally include such functions as data buffering/posting and PCI central functions such as arbitration.
The PCI specification provides for totally software driven initialization and configuration via a separate configuration address space. During the configuration, the PCI bus master processor can read or write to the configuration space of each device connected to the local PCI bus in order to map the device to the memory address space and assign address spaces to the connected devices. The architecture and operation of the PCI local bus is described in "PCI Local Bus Specification," Revisions 2.0 (April, 1993) and Revision 2.1s, published by the PCI Special Interest Group, 5200 Elam Young Parkway, Hillsboro, Oregon, which specifications are incorporated herein by reference in their entirety.
A PCI to PCI bridge provides a connection path between two independent PCI local busses. The primary function of the bridge is to allow transactions between a master on one PCI bus and a target device on another PCI bus. The PCI Special Interest Group has published a specification on the architecture of a PCI to PCI bridge in "PCI to PCI Bridge Architecture Specification," Revision 1.0 (April 10, 1994), which specification is incorporated herein by reference in its entirety. This specification defines the following terms and definitions:
initiating bus--the master of a transaction that crosses a PCI to PCI bridge is said to reside on the initiating bus. PA1 target bus--the target of a transaction that crosses a PCI to PCI bridge is said to reside on the target bus. PA1 primary interface--the PCI interface of the PCI to PCI bridge that is connected to the PCI bus closest to the CPU is referred to as the primary PCI interface. PA1 secondary interface--the PCI interface of the PCI to PCI bridge that is connected to the PCI bus farthest from the CPU is referred to as the secondary PCI interface. PA1 downstream--transactions that are forwarded from the primary interface to the secondary interface of a PCI to PCI bridge are said to be flowing downstream. PA1 upstream--transactions forwarded from the secondary interface to the primary interface of a PCI to PCI bridge are said to be flowing upstream.
Thus, a PCI to PCI bridge has two PCI interfaces, the primary and secondary. Each interface is capable of either master or target operation. The bridge functions as a target on the initiating bus on behalf of the target that actually resides on the target bus. Likewise, the bridge functions as a master on the target bus on behalf of the master that actually resides on the initiating bus.
A master processor configures the PCI bridges, PCI local busses, and devices connected thereto and maps such devices to the memory address space using a combination of type 0 and type 1 configuration operation commands. Type 0 configuration commands are not forwarded across PCI to PCI bridges. Type 0 configuration commands are used to configure PCI to PCI bridges or other PCI devices that are connected to the PCI bus on which the type 0 configuration command is generated. Type 1 configuration commands can be forwarded by PCI to PCI bridges to any level within the PCI bus hierarchy, such as further busses and bridges. A PCI to PCI bridge that receives a type 1 configuration command converts the command to a type 0 command to configure devices connected to the bridge's secondary interface if the bus number in the type 1 command matches the bus number of the bus connected to the bridge's secondary interface, i.e., the secondary bus number. The bridge will forward a type 1 configuration command down its secondary interface to another PCI bridge if the address specified in the type 1 command is between the bus number of the bus attached to the secondary interface of the bridge and a subordinate bus number of the bridge. The subordinate bus number is the number of the highest numbered PCI bus that is behind or subordinate to a bridge.
During system initialization, the BIOS generates the secondary bus number, the primary bus number, which is the bus number of the bus that the primary interface of the bridge is connected to, and the subordinate bus number and records such information within PCI bridge registers. The BIOS that finds a PCI to PCI bridge further needs to map all devices that reside below the bridge on the primary interface to memory address space.
One limitation in the prior art is that a PCI subsystem, comprised of a hierarchical arrangement of local PCI busses, PCI to PCI bridges, and other devices, cannot be configured separately by two different processor bus masters as part of a failover system. For instance, primary and secondary processors may be connected to a PCI subsystem and each capable of functioning as a bus master. During initialization, the bridge for the primary processor will assign bus numbers to all the busses in the subsystem and assign address space to all devices and bridges within the subsystem. If the primary processor failed, then in a failback system, the secondary processor would attempt to assume control of the subsystem. However, limitations in the PCI prior art would prevent the secondary processor from successfully taking the place of the primary processor. In the current PCI prior art, the secondary processor would reconfigure the PCI bridges, busses and other devices connected to the system with bus numbers and addresses that conflict with the numbers and addresses assigned by the failed primary processor. The conflicting configurations assigned by the two bus masters prevent a dual master processor design in a PCI to PCI bridge failover subsystem. | {
"pile_set_name": "USPTO Backgrounds"
} |
(1) Field of the Invention
The present invention relates to correcting an estimated range of a source-to-sensor distance in response to a range difference error that is determined by comparing and processing data collected in a near field (or otherwise) from a sensor and from a reference.
(2) Description of the Prior Art
Often, equipment such as hydrophones are tested and calibrated during the manufacturing and operational phases of the life cycle of the equipment. As such, test equipment for hydrophone applications is arranged in various locations relative to the units of the equipment undergoing testing. Common difficulties encountered while performing the tests include measuring the various distances between and amongst acoustic sources and reference hydrophones and the units under test. Errors in measurement of the distance affect the accuracy of the measurements made, and thus degrade equipment performance when the equipment is not optimally calibrated. Furthermore, relative motion among the acoustic source, reference hydrophone and the unit under test affects the accuracy of the measurements made. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to well plug additives and to methods of making such additives, to well plug treatment fluids made therefrom and methods of making such fluids, to methods of modifying a well fluid using such additives and/or fluids, to methods of operating a well using such additives and/or fluids, to methods of plugging a well using such additives and/or fluids. In another aspect, the present invention relates to well plug additives comprising polymer, crosslinking agent, a filter aid, and optionally, reinforcing materials and to methods of making such additives, to well plug treatment fluids made therefrom and methods of making such fluids, to methods of modifying a well fluid using such additives and/or fluids, to methods of operating a well using such additives and/or fluids, to methods of plugging a well using such additives and/or fluids. In even another aspect, the present invention relates to well plug additives comprising a dry mixture of polymer, crosslinking agent, a filter aid, and optionally, reinforcing materials and to methods of making such additives, to well plug treatment fluids made therefrom and methods of making such fluids, to methods of modifying a well fluid using such additives and/or fluids, to methods of operating a well using such additives and/or fluids, to methods of plugging a well using such additives and/or fluids. In still another aspect, the present invention relates to well plug additives comprising polymer and diatomaceous earth (“DE”) and to methods of making such additives, to well plug treatment fluids made therefrom and methods of making such fluids, to methods of modifying a well fluid using such additives and/or fluids, to methods of operating a well using such additives and/or fluids, to methods of plugging a well using such additives and/or fluids.
2. Description of the Related Art
Wells employed in the production of oil and gas are abandoned inter alia because they reach the end of their useful life or they become damaged beyond repair. State and federal regulations require that abandoned wells be plugged to protect safety and environmental interests. The well is commonly plugged by pumping Portland cement into the wellbore and curing the cement in situ.
Formulation of Portland cement in the field is largely a product of trial and error by field personnel to meet irregularities in the cementing composition and the downhole environment. Cement quality control is difficult to achieve under such conditions. As a result, Portland cement cured in situ can exhibit cracking, shrinking, or poor adhesion to wellbore tubulars. An imperfect Portland cement plug can enable undesirable fluid flow through the wellbore via leaks along or through the cement.
U.S. Pat. No. 4,730,675, issued Mar. 15, 1988 to Wygant and Sydansk note that a process was then needed which employed a plugging material having a broad range of highly controllable and predictable set-up times providing ease of operation and design at a relatively low cost. Wygant and Sydansk further noted that a process was then needed employing a substitute material for Portland cement in conventional plugging processes which forms a more effective plug and seals the wellbore indefinitely.
U.S. Pat. No. 4,730,675 proposes the use of a water soluble carboxylate crosslinking polymer along with a chromic carboxylate complex crosslinking agent in the plugging of an abandoned well, and at column 1, lines 61-63, specifically teaches away from the use of solids in the plugging fluid injected into the wellbore.
Thus, while U.S. Pat. No. 5,377,760, issued Jan. 3, 1995 to Merrill discloses addition of fibers to an aqueous solution of partially hydrolyzed polyacrylamide polymer, with subsequent injection into the subterranean to improve conformance, the performance requirements of conformance improvement treatment polymers are so different from those of polymers for plugging an abandoned well, that such would not necessarily work for well plug treatment. Furthermore, Wygant and Sydansk teach away from injection a solid containing polymer into the wellbore to plug an abandoned well.
Additionally, Merrill's conformance treatment method of mixing the fibers with the polymer solution followed by injection, requires a multiplicity of storage and mixing tanks, and a metering system which must be operated during the operation of the well. Specifically, a first tank will store a water and polymer solution, a second tank will store a water and cross-linking solution, and a third tank will be used to mix fibers with polymer solution from the first tank to create a polymer/fiber slurry. This polymer/fiber slurry is then metered from the third tank and combined with crosslinking solution metered from the second tank to the well bore.
As an advance over the above prior art, U.S. Pat. No. 6,098,712, issued Aug. 8, 2000, to Boyce D. Burts, Jr., for “Method of plugging a well,” discloses an additive including a dry mixture of water soluble crosslinkable polymer, a crosslinking agent, and a reinforcing material of fibers and/or comminuted plant materials. The method of forming a fluid includes contacting the additive with water or an aqueous solution, with a method of treating the formation further including the step of injecting the fluid into the formation.
While not believed to be related prior art because they relate to different types of well operations, for completeness, attention is directed to five other similar “dry mixture” patents by Boyce D. Burts, Jr., which were filed on the same day (Oct. 31, 1997) as the '712 patent: U.S. Pat. No. 6,218,343, issued Apr. 17, 2001, for “Additive for, treatment fluid for, and method of plugging a tubing/casing annulus in a well bore,” U.S. Pat. No. 6,102,121, issued Aug. 15, 2000, for “Conformance improvement additive, conformance treatment fluid made therefrom, method of improving conformance in a subterranean formation,” U.S. Pat. No. 6,016,879, issued Jan. 25, 2000, for “Lost circulation additive, lost circulation treatment fluid made therefrom, and method of minimizing lost circulation in a subterranean formation,” U.S. Pat. No. 6,016,871, issued Jan. 25, 2000, for “Hydraulic fracturing additive, hydraulic fracturing treatment fluid made therefrom, and method of hydraulically fracturing a subterranean formation,” and U.S. Pat. No. 6,016,869, issued Jan. 25, 2000, for “Well kill additive, well kill treatment fluid made therefrom, and method of killing a well.”
A number of patents discuss the use of diatomaceous earth (“DE”) in a well operation.
U.S. Pat. No. 3,380,542, issued Apr. 30, 1968 to Clear, for restoring lost circulation discloses a oil-based drilling fluid, containing a slurry of diatomite and asbestos, used to restore lost circulation during well drilling operations.
U.S. Pat. No. 4,369,844, issued Jan. 25, 1983 to Clear, discloses that various formation sealing agents have been used in the art to form formation seals and/or filter cakes on the wall of a well bore, including diatomaceous earth.
U.S. Pat. No. 4,110,225, issued Aug. 29, 1978 to Cagle, discloses that zones of lost circulation and other undesired fluid communication channels into a wellbore are sealed by isolating a volume in the well including such a zone and applying greater than formation pressure to a novel slurry spotted in the zone until it hardens into a solid, drillable seal. The slurry contains per barrel from 5-50 pounds diatomaceous mix, from about 35 to about 350 pounds of oil well cement, and at a minimum about 5 to 6 pounds of a flake type lost-circulation agent. This '225 patent cites a number of patents that disclose cement/diatomaceous earth compositions, including U.S. Pat. Nos. 2,585,336; 2,793,957; 2,961,044; 3,467,198; and 3,558,335.
Regarding these patents, the '225 patent notes the following: Regarding U.S. Pat. No. 2,585,336, the '225 patent notes, “a mixture is made using from 2% to 100% diatomaceous earth, compared to the content of the cement in the slurry. The aim of the inventors was to prevent perlite from settling and to produce a lightweight cement. The diatomaceous earth-cement described in the disclosure is a mixture of Portland cement, perlite and diatomaceous earth, lime, and asbestos fibers.” Regarding U.S. Pat. No. 2,793,957, the '225 patent notes, “refers to a highly permeable cement formed by use of the same basic mixtures of diatomaceous earth with Portland cement, the diatomaceous earth present being from five to seven times the proportion of the Portland cement in the slurry. The aim of the inventors was to produce a light highly permeable cement, entirely opposite to the purpose of my invention.” Regarding U.S. Pat. No. 2,961,044, the '225 patent notes, “discusses and claims a cement composition which has diatomaceous earth in the amounts of from 30% to 70% of the Portland cement. The reason for using the diatomaceous earth was to prevent the strength retrogression of a salt-saturated cement. Thus, while Shell wishes (among other uses) to employ his mixture for squeeze cementing, he produces a relatively high-strength cement plug. There is a real tendency when redrilling such a plug for the bit to be deflected or sidetracked so that the new hole is beside rather than through the bore and the seal is ineffective. This is completely different from my invention which minimizes such tendency by producing a plug at least as drillable as the formation in which it is set. Also, Shell is directed to operations using salt-saturated cement slurries, while I prefer using a fresh or brackish water slurry. I employ lost-circulation agents; he makes no teaching of using such additives. Accordingly, his teaching is quite far from mine.” Regarding both U.S. Pat. Nos. 3,467,198 and 3,558,335, the '225 patent notes, “describe cement compositions having diatomaceous mix present in the amounts from 0.5% to 10% of the amount of Portland cement present to prevent solids-settling.”
U.S. Pat. No. 4,369,844, issued Jan. 25, 1983 to Clear, discloses slurries to seal permeable earth formations encountered in the drilling of wells, comprising finely divided paper, diatomaceous earth, and in a further embodiment, lime. A slug of the slurry is spotted at the locus of the permeable formation and defluidized to form a formation seal on which a mud sheath is then deposited.
U.S. Pat. No. 4,505,751, issued Mar. 19, 1985, discloses a silicate/silica cement in oil field applications, including diatomaceous earth as a species of silica compound.
While not believed to be analogous prior art because it relates to earthen pits (for example a ditch) and not to subterrean wellbores nor well operations, U.S. Pat. No. 5,947,644, issued Sep. 7, 1999 to Gibbons et al., is included herein for completeness because it discloses a gelable slurry of aqueous solvent, a crosslinkable polymer, a crosslinking agent, and unconsolidated solids such as diatomaceous earth. This gelable slurry is placed in an earthen pit and allowed to form into a fluid impermeable barrier wall in the earthen pit. The polymer serves to bind the unconsolidated solids to convert the gelable slurry to a nondeformable gelled continuum of consolidated solids, which forms the barrier wall in the earthen pit. As disclosed in the '644 patent in the Summary of the Invention section, at col. 1, lines 57-67, this gelable slurry is prepared by first forming a liquid gelation solution of the polymer and crosslinking agent, to which is subsequently mixed with the unconsolidated solids, or alternatively, by sequentially mixing the aqueous solvent, crosslinkable polymer, and polymer crosslinking agent with the unconsolidated solids.
Thus, in spite of the advancements in the prior art, there still is a need for further innovation in the well plug additives.
There is need for further innovation for well plug additives utilizing a water soluble polymer.
There is another need for a well plug additive which would allow for simplification of the mixing equipment.
These and other needs in the art will become apparent to those of skill in the art upon review of this specification, including its drawings and claims. | {
"pile_set_name": "USPTO Backgrounds"
} |
Magnetic tape is now utilized for storage of digital and analog information in applications ranging from computers to video recordings. In normal use, magnetic tape picks up airborne dirt particles and oxide flakes from its surface. The presence of these contaminants on the tape causes errors in the writing of information to and reading information from the tape. The contaminated areas move the tape away from the read and write heads resulting in a failure to record or playback the intended information.
This problem with accumulation of dirt and oxide has been well recognized in the art. Fixed and rotating single blade devices have been used to hone contaminants from the surface of magnetic tape. A significant problem with single blade devices is heavy blade wear due to the hardness of the oxide coatings on the tape.
A device with multiple honing surfaces has also been used to clean magnetic tape. The use of multiple surfaces reduces the wear problem of single honing surface devices. A rotating cylindrical tube is utilized with a plurality of slots spaced about its circumference. A vacuum line connected to an aperture provided at the base of the tube serves to withdraw the particles cleaned from the tape. A problem with this method is the high expense and complication of fabricating a hollow slotted cylindrical tube of a material sufficiently hard to withstand the abrasion of the oxide coatings on the tape. Another problem with the tube design is that it heats up due to inadequate cooling airflow. The shape of the slot performs the dual functions of defining the honing surface and providing an air conduit for the removal of particles cleaned from the tape. This does not provide an effective means of controlling the flow of air past the tape or through the slot for needed cooling and self cleaning of the honing surface. As a result, the high temperatures generated by friction cause the loose oxide and dirt removed from the tape to become welded to the honing surfaces. This mandates frequent cleaning of the slotted tube design. | {
"pile_set_name": "USPTO Backgrounds"
} |
In general, in semiconductor manufacturing devices, the development of photoresists facilitates the patterning of small-dimensioned electronic and optical devices. An example of such photoresists is deep ultra violet (DUV) photoresists. The dimensions of DUV photoresist patterns are considerably smaller than those of conventional photoresist patterns. A metal etching process requires the formation of metal lines having a space smaller than 0.25 μm therebetween.
However, since such photoresist is sensitive to the reflectance of the metal lines, the reflectance needs to be reduced in order to form a successful pattern of the photoresist. Therefore, an anti-reflective layer of oxide has been used on the metal lines.
In an in-situ etching of the anti-reflective layer in a metal etching chamber, a gas having fluorine, e.g., CHF3, has been commonly used. However, in the etching process, a process for forming an initial plasma using a gas having fluorine has a certain drawback in that a higher pressure is required to turn on plasma.
Therefore, as shown in Table 1 in conventional plasma ignition processes, a preceding step having a higher pressure than that of a succeeding step is introduced to turn on plasma. Those skilled in the art are able to understand that the values shown in table 1 may vary.
TABLE 1CHF3 flowPressureSourceBiasrateAr flow rate(mTorr)power(W)power(W)(sccm)(sccm)Preceding12˜20600˜1000100˜2005˜3050˜90stepSucceeding6˜8600˜1000100˜2005˜3050˜90step
However, such conventional processes have a problem in that an error may occur due to a difference in the pressure of a chamber between the preceding step and the succeeding step. | {
"pile_set_name": "USPTO Backgrounds"
} |
Despite considerable progress in the field of porous solids, major challenges remain in the synthesis of ordered mesostructured materials with high metal content from the coassembly of macromolecular surfactants and inorganic species. The ability to control the structure of metals at the mesoscale (2 to 50 nm) helps to promote the development of improved fuel cell electrodes and may also assist in the miniaturization of optical and electronic materials for data transmission, storage, and computation (A. Haryono, W. H. Binder, Small 2, 600 (2006); A. C. Balazs, T. Emrick, T. P. Russell, Science 314, 1107 (2006)).
An early route to preparing mesoporous metals involves the dealloying of a less noble metal from a bimetallic alloy; this has been used for the preparation of Raney nickel and other metals (M. Raney, U.S. Pat. No. 1,628,190 (1927)). Dealloying processes provide limited control over structural parameters such as pore geometry and order. In contrast, block copolymer self-assembly or templating with metal species provides access to highly ordered structures. Synthetic routes to such structures have included adsorbing and then reducing metal ions within a preassembled block copolymer scaffold (Y. N. C. Chan, R. R. Schrock, R. E. Cohen, Chem. Mater. 4, 24 (1992)) and coassembling ligand-stabilized nanoparticles (NPs) with block copolymers (D. E. Fogg, L. H. Radzilowski, R. Blanski, R. R. Schrock, E. L. Thomas, Macromolecules 30, 417 (1997)). More recently, polymer-coated NPs that behave like surfactants have been isolated at the interface of block copolymer domains, which can create a bicontinuous morphology at higher loadings (B. J. Kim, G. H. Fredrickson, C. J. Hawker, E. J. Kramer, Langmuir 23, 7804 (2007)).
Despite this progress, the conversion of metal polymer hybrids into porous mesostructured materials with ordered and large pores (≧5 nm) has not been accomplished, in part because of the low volume fraction of metals in most hybrids and the widespread use of gold, which has a high diffusion coefficient and therefore retains its mesostructure only at low temperatures (P. Buffat, J.-P. Borel, Phys. Rev. A 13, 2287 (1976); R. Li, K. Sieradzki, Phys. Rev. Lett. 68, 1168 (1992); J. Erlebacher, M. J. Aziz, A. Karma, N. Dimitrov, K. Sieradzki, Nature 410, 450 (2001)). Although a protective organic layer can be added to metal NPs to prevent uncontrolled aggregation, even a thin organic layer represents a considerable volume of the overall material: For example, a 1-nm-diameter metal NP with a relatively thin 1-nm organic shell is just 4% metal by volume. As a result, the typical metal content in most block copolymer-metal NP hybrids is only a few volume %, and the prospects for converting the hybrid into an ordered porous mesostructured material, in which the metal would have a volume fraction between 60 and 75% for an inverse hexagonal structure, are poor. Mesoporous metals have been synthesized at a smaller length scale, with 2- to 4-nm pores, through the coassembly of metal ions with small-molecule surfactants followed by reduction (G. S. Attard et al., Science 278, 838 (1997); G. S. Attard, C. G. Göltner, J. M. Corker, S. Henke, R. H. Templer, Angew. Chem. Int. Ed. Engl. 36, 1315 (1997); Y. Yamauchi, T. Yokoshima, T. Momma, T. Osaka, K. Kuroda, J. Mater. Chem. 14, 2935 (2004); J. Jiang, A. Kucernak, Chem. Mater. 16, 1362 (2004)). The small pore size, however, limits the flow of liquids through the material, which is essential for many applications (D. Y. Zhao et al., Science 279, 548 (1998); M. E. Davis, Nature 417, 813 (2002)). Metals have also been deposited onto (W. A. Lopes, H. M. Jaeger, Nature 414, 735 (2001)) or into (J. Chai, D. Wang, X. Fan, J. M. Buriak, Nat. Nanotechnol. 2, 500 (2007)) thin films of block copolymers to create metal wires, but the surface dependent nature of the metal deposition most likely limits these processes to two-dimensional materials.
There is therefore a need in the art for mesostructured metal NP-block copolymer hybrids with exceptionally high NP loadings and tunable phase-separated morphologies with feature sizes>10 nm. There is also a need in the art for metal-rich mesostructures with ordered and large (≧5 nm) uniform pores.
Citation or identification of any reference in Section 2, or in any other section of this application, shall not be considered an admission that such reference is available as prior art to the present invention. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to semiconductor vapor phase growing apparatus. So called vapor phase growing apparatus in which vapor phase growth is performed on a semiconductor wafer has called attention in recent years because semiconductor tips are used in various industrial fields. In the vapor phase growing apparatus now being used, a sequence program (hereinafter termed a process program) indicative of the progress of the process in a reaction furnace is excecuted by a system in which the progress of the sequence is designated by a pin board switch or the like, and the flow quantity of the gas used and the furnace temperature are designated by setting variable resistors contained in a control device by an operator.
FIG. 1 is a block diagram explaining the conventional manner of controlling the progress of the process in a reaction furnace with a pin board switch system.
In FIG. 1, pins are inserted into a set panel of a pin board switch according to an order of execution of a process program PPi (i=1-17), and the set panel is constructed such that the sequence times of the process program of the respectively designated orders can be set in the units of hours, minutes and seconds.
To a relay ladder circuit B are applied instructions corresponding to the order of a sequence, that is instructions that make effective the contents of process programs pp2, pp3, pp4, pp6, pp5 and pp6 corresponding to steps 1 , 2 , . . . 6 , 7 so as to give control signals to valves or like means corresponding to respective instructed processes. With such pin board system, however, only the times of respective process sequences can be set, but the flow quantity of the gas used and the furnace temperature must be set with other measures, for example variable resistors.
In addition to the pin board system shown in FIG. 1, a control device utilizing a general purpose sequence controller has also been proposed. In such control device too, the flow quantity and the furnace temperature are not designated by directly programmed data so that such setters as variable resistors are necessary.
Furthermore, in the pin board system described above, only one group of a series of programs corresponding to one cycle of the reaction furnace, that is only one set of pp2.fwdarw.pp3.fwdarw.pp1.fwdarw.pp4.fwdarw.pp6.fwdarw.pp5.fwdarw.pp7 shown in FIG. 1 can be loaded so that in order to operate a plurality of reaction furnaces a plurality of pin board panel units corresponding thereto should be provided. In this regard, since the general purpose controller contains a timer, only a problem of time designation program is involved. Where the general purpose program is used, since its process program is not contructed to designate the gas flow quantity and the furnace temperature, setters of these parameters have been used. Principal reasons are as follows.
1. Although the system program of a general purpose sequence controller is prepared by its maker, just like the pin board system, the decoding items of the content of the process program according to its system program lack the items regarding gas flow quantity used and the reaction furnace designation temperature. For this reason, the gas flow quantity and the furnace temperature are set by such independent setters as variable resistors or the like manipulated by the operator.
2. From the standpoint of the operator, manipulation of the general purpose sequence controller, the ability of directly controlling the gas flow quantity and the furnace temperature are equivalent to those of the pin board system so that the operator can operate the reaction furnace without any caution. Especially, correction of set values can be made readily.
3. From the standpoint of the maker, where manual setters for the gas quantity and the furnace temperature are omitted, it is necessary to modify the system program so as to include a program for correcting the content of the process program as a portion of the system program. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Technical Field
The present invention relates to exercise apparatus.
2. Description of Related Art
Live yoga, Pilates and body toning classes at gyms and yoga studios have limitations. They're often crowded, only offered at scheduled times of the day, and may not match the skill level or physical needs of the practitioner. The only way to be sure a live class meets the particular needs of an attendee is through private instruction, which may cost more than $100 per hour. | {
"pile_set_name": "USPTO Backgrounds"
} |
In the case of a lighting device of the type described in the introduction, a primary light can be generated by means of the primary light source. During operation of the lighting device, said primary light hitherto has impinged on a disk-shaped, rotating first support wheel having a plurality of different phosphor regions. The different phosphor regions generate differently wavelength-converted light (that is to say light of different colors or different spectral compositions). As a result of the rotation of the support wheel, the phosphor regions are successively activated and a temporally serial sequence of differently colored secondary light sections is thus generated. The phosphor regions are typically arranged in an annular fashion on the first support wheel and form sectors thereof.
However, the primary light currently incident on a phosphor region is typically not completely converted, and so the secondary light emitted by said phosphor region includes both a (usually dominant) wavelength-converted light component and an undesired non-wavelength-converted primary light component. In order to be able to output a substantially pure wavelength-converted light component, an associated filter region is disposed downstream of such a phosphor region and filters out the primary light component of the secondary light. Depending on the type of wavelength-converted light and the proportion thereof in the secondary light, a different filter region can be used in order to optimize an efficiency of the lighting device. In order to be able to provide a filter region matching a phosphor region, the filter regions are arranged in an annular fashion on a circular-disk-shaped second support wheel. The second support wheel has to be operated synchronously with the first support wheel in order to be able to maintain a high efficiency and to avoid color corruption as a result of non-matching combinations of phosphor regions and filter regions.
The output light beam present downstream of the second support wheel is temporally serially composed analogously to the secondary light, wherein the individual (temporally serial) sections thereof in each case correspond to a predetermined combination of a currently active phosphor region and an associated filter region. The relative duration of the sections can be set via the length of the phosphor regions (and thus the corresponding length of the associated filter region). If the sequence of the sections occurs rapidly enough, the individual sections are no longer resolved by a human observer, and the output light beam is perceived as a uniform mixed light. The individual sections act as different color components of the mixed light.
The support wheels are typically angled with respect to one another and have to be precisely synchronized, which necessitates a considerable constructional outlay, e.g. owing to the use of high-quality and thus expensive drive motors for the support wheels and on account of complex synchronization control. A probability of failure of the support wheels is also comparatively high. | {
"pile_set_name": "USPTO Backgrounds"
} |
It is conventionally known to create an NC tape for driving an NC machine tool by automatic programming, saving time and obtaining an accurate program.
However, when a program for machining a material 2 such as the round rod as shown in FIG. 1 with a two-saddle turret lathe to obtain a product having a hole 3 and an outer shape 1 is created by an automatic programming apparatus, it is necessary to determine which machining steps are to be performed by respective saddles and also whether machining can be performed by both saddles simultaneously. For example, the machining steps shown in FIG. 1 include rough cutting step N1 and finishing step N2 as outer-diameter machining, drilling step N3, rough cutting step N4 and finishing step N5 as inner-diameter machining of the hole formed by the drilling step N3, and rough cutting step N6 and finishing step N7 as face grinding. Among these, the rough cuttings steps N1, N4 and N6 can be performed simultaneously with the drilling step N3, but cannot be performed simultaneously with the finishing steps. Therefore, each machining step is assigned to a saddle. It is then determined which of the steps are to be performed simultaneously and when to start machining, thereby creating a program for each of the saddles. | {
"pile_set_name": "USPTO Backgrounds"
} |
This invention relates to a binarizing system of picture image signals. In a facsimile device, for example, analog picture image signals produced by scanning a manuscript with a line sensor are binarized according to a predetermined threshold value. Generally, the level of the picture image signal varies depending upon such factors as the tone or concentration of the picture image, the thickness of lines, whether the lines are vertical or horizontal, states of surrounding picture images, or the like so that when the picture image signals are binarized as they are, it is impossible to obtain good image quality. For example, a fine black line in a white background, a continuous pattern of fine white and black lines, and a fine white line in a black background have different signal levels so that informations would be lost irrespective of the settings of threshold values as will be described later in more detail.
For this reason, in the prior art a correction circuit has been provided before the binarizing circuit for correcting contrast of the picture image signals. Although various types of correction circuits have been proposed, a satisfactory correction circuit is not yet available. For example, according to one type of correction circuit, where the difference in the signal levels of the picture image signals of adjacent picture elements and the picture image signal of a picture element to be corrected is small, substantially no correction is made, while for a picture image in which the level of the picture image signal varying slowly, that is, for a picture image whose contrast is vague, satisfactory correction could not be made. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention generally relates to an air conditioning system, such as for use in cooling and heating rooms or similar compartments, and more particularly, to an air conditioning system which heats and cools by radiation. Air conditioning system, as used herein, refers to a system that both cools and heats rooms. Such a system may include what is commonly known as a heat pump type of air conditioning system.
2. Description of the Prior Art
Generally, a conventional air conditioning system used in a house or similar dwelling cools the rooms in the house or dwelling in a cooling mode of operation, by supplying a forced flow of cooled air from an indoor unit of the system. However, such a forced air cooling operation often supplies uncomfortable drafts of cool air to the people in the rooms. In contrast, some conventional air conditioning systems may be structured to heat rooms by radiation (i.e., radiant energy heating) to prevent supplying uncomfortable drafts of heated air into the rooms. For example, an air conditioning system may be adapted for radiant energy heating, whereby a radiation surface is formed under or on the surface of a floor, and pipes that circulate high temperature refrigerant from a compressor operating during a heating cycle are arranged on the radiation surface. Conversely, cooling of air in these rooms may also be accomplished by radiation (i.e., radiation cooling) by reversing the flow of refrigerant in such an air conditioning system, whereby the pipes arranged on the radiation surface circulate cooled refrigerant during a cooling mode of operation.
Nevertheless, conventional air conditioning systems experience a significant problem if radiation cooling is attempted utilizing a similar structure to that used for radiant energy heating. That is, since the radiation surface is heat exchanged directly by the cooled refrigerant, the humid air surrounding the radiation surface is condensed into dew or droplets of water onto the radiation surface. This water can freeze on the surface and substantially reduce the cooling efficiency of the system. Consequently, even if a conventional air conditioning system may be capable of heating rooms by radiation during a heating mode, such a system is still required to cool the rooms by blowing cool air into the rooms during the cooling mode of operation. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
THIS INVENTION relates to dowel sleeves.
In particular, the invention relates, but is not limited to, dowel sleeves for the construction of concrete slabs; and to parts or components for the dowel sleeves.
Throughout the specification, the term “construction plate” shall be used to include key joint plates, contraction plates and expansion plates for the construction of concrete slabs; and like construction plates used in building construction.
2. Prior Art
Dowel sleeves, which are typically of circular or rectangular cross-section, are commonly used to accommodate expansion and/or contraction of adjacent concrete slabs at a joint, where one end of each dowel is “locked” into one of the concrete slabs and the other end is slidably received within a respective dowel sleeve to allow controlled lateral movement, relative to the joint, between adjacent concrete slabs in a generally horizontal direction (i.e. along an axis substantially perpendicular to the joint between the adjacent slabs; but limiting any horizontal (or lateral) movement (i.e., along an axis parallel to the joint) and/or any vertical displacement between the adjacent concrete slabs.
Typically, the prior art dowel sleeves are formed from plastics material (which may have been wholly- or partially-recycled); where one end (i.e., the outer end) of the dowel sleeve is fixed, e.g., by nailing to a construction plate, and the other end is supported by an integral leg or a “chair”, to locate the dowel sleeve before the concrete is poured for the concrete slab in which at least a portion of the dowel sleeve is to be embedded.
The one (or outer) end may be engaged with an end cap, of complementary external shape, nailed or otherwise fixed to the construction plate.
Alternatively, the one (or outer) end of the dowel sleeve may be engaged in complementary formation(s) on the construction plate.
The workers installing the dowel sleeves must align each with respective holes through the construction plate, where the dowels extend through the holes; fix the one (or outer) ends of the dowel sleeves to the construction plate; and align and support the dowel sleeves so that they will not be displaced prior to/during the concrete pour to ensure the designed (or allowable) relative expansion/contraction movement between the slabs can be achieved without unwanted horizontal (lateral) and/or vertical displacement between the adjacent concrete slabs. | {
"pile_set_name": "USPTO Backgrounds"
} |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.