source stringlengths 31 227 | text stringlengths 9 2k |
|---|---|
https://en.wikipedia.org/wiki/Cylindric%20numbering | In computability theory a cylindric numbering is a special kind of numbering first introduced by Yuri L. Ershov in 1973.
If a numbering is reducible to then there exists a computable function with . Usually is not injective, but if is a cylindric numbering we can always find an injective .
Definition
A numbering is called cylindric if
That is if it is one-equivalent to its cylindrification
A set is called cylindric if its indicator function
is a cylindric numbering.
Examples
Every Gödel numbering is cylindric
Properties
Cylindric numberings are idempotent: |
https://en.wikipedia.org/wiki/Cross-conjugation | Cross-conjugation is a special type of conjugation in a molecule, when in a set of three pi bonds only two pi bonds interact with each other by conjugation, while the third one is excluded from interaction. Whereas a normal conjugated system such as a polyene typically has alternating single and double bonds along consecutive atoms, a cross-conjugated system has an alkene unit bonded to one of the middle atoms of another conjugated chain through a single bond. In classical terms, one of the double-bonds branches off rather than continuing consecutively: the main chain is conjugated, and part of that same main chain is conjugated with the side group, but all parts are not conjugated together as strongly. Examples of cross-conjugation can be found in molecules such as benzophenone, , p-quinones, dendralenes, radialenes, fullerene, and Indigo dye. The type of conjugation affects reactivity and molecular electronic transitions. |
https://en.wikipedia.org/wiki/Tetraview | A tetraview is an attempt to graph a complex function of a complex variable, by a method invented by Davide P. Cervone.
A graph of a real function of a real variable is the set of ordered pairs (x,y) such that y = f(x). This is the ordinary two-dimensional Cartesian graph studied in school algebra.
Every complex number has both a real part and an imaginary part, so one complex variable is two-dimensional and a pair of complex variables is four-dimensional. A tetraview is an attempt to give a picture of a four-dimensional object using a two-dimensional representation—either on a piece of paper or on a computer screen, showing a still picture consisting of five views, one in the center and one at each corner. This is roughly analogous to a picture of a three-dimensional object by giving a front view, a side view, and a view from above.
A picture of a three-dimensional object is a projection of that object from three dimensions into two dimensions. A tetraview is set of five projections, first from four dimensions into three dimensions, and then from three dimensions into two dimensions.
A complex function w = f(z), where z = a + bi and w = c + di are complex numbers, has a graph in four-space (four dimensional space) R4 consisting of all points (a, b, c, d) such that c + di = f(a + bi).
To construct a tetraview, we begin with the four points (1,0,0,0), (0, 1, 0, 0), (0, 0, 1, 0), and (0, 0, 0, 1), which are vertices of a spherical tetrahedron on the unit three-sphere S3 in R4.
We project the four-dimensional graph onto the three-dimensional sphere along one of the four coordinate axes, and then give a two-dimensional picture of the resulting three-dimensional graph. This provides the four corner graph. The graph in the center is a similar picture "taken" from the point of view of the origin.
External links
http://www.math.union.edu/~dpvc/professional/art/tetra-exp.html
http://www.maa.org/cvm/1998/01/sbtd/article/tour/tetra-Z3/tetra-Z3.html
Functions an |
https://en.wikipedia.org/wiki/Landolt%20C | The Landolt C, also known as a Landolt ring, Landolt broken ring, or Japanese vision test, is an optotype: a standardized symbol used for testing vision. It was developed by the Swiss-born ophthalmologist Edmund Landolt.
The Landolt C consists of a ring that has a gap, thus looking similar to the letter C. The gap can be at various positions (usually left, right, bottom, top and the 45° positions in between) and the task of the tested person is to decide on which side the gap is. The size of the C and its gap are reduced until the subject makes a specified rate of errors. The minimum perceivable angle of the gap is taken as measure of the visual acuity. It is generally practised in the laboratory.
The stroke width is of the diameter, and the gap width is the same. This is identical to the letter C from a Snellen chart. The Landolt C is the standard optotype for acuity measurement in most European countries. It was standardized, together with measurement procedures, by the German DIN, as DIN 58220 (now EN ISO 8596).
Although accepted as a gold standard, this optotype has its own inherent problems, possibly due to higher brain function where the gap will appear closed near the limit of resolution, especially when the gap is at the 6 o'clock position. This is not due to the structure of the cornea or lens, and it is not due to astigmatic errors.
See also
Edmund Landolt
Visual acuity
E chart
Golovin–Sivtsev table |
https://en.wikipedia.org/wiki/Microsoft%20Notification%20Protocol | Microsoft Notification Protocol (MSNP, also known as the Mobile Status Notification Protocol) is an instant messaging protocol developed by Microsoft for use by the Microsoft Messenger service and the instant messaging clients that connect to it, such as Skype since 2014, and the earlier Windows Live Messenger, MSN Messenger, Windows Messenger, and Microsoft Messenger for Mac. Third-party clients such as Pidgin and Trillian can also communicate using the protocol. MSNP was first used in a publicly available product with the first release of MSN Messenger in 1999.
Technical details
Any major change made to the protocol, such as a new command or syntax changes, results in a version-number incremented by one in the format of MSNP#. During October 2003, Microsoft started blocking access to Messenger service using versions below MSNP8.
Starting on September 11, 2007, Microsoft forces most current users of MSN Messenger to upgrade to Windows Live Messenger 8.1 due to security considerations.
Version history
MSNP1
MSNP1 has never been public. It is believed it was used during the early stages of design and development with MSN Messenger 1
MSNP2
A pre-release version was made available to developers in 1999 in an Internet Draft. However, the production version differed from the published version in a few subtle ways.
MSNP3
Both MSNP2 and MSNP3 were supported by MSN Messenger 2.0. MSNP3 was also supported by the first version of the WebTV (MSN TV) Messenger client released in its Summer 2000 upgrade, and introduces a new command specifically for use by those clients — IMS — which allows the ability for a client to allow or block new switchboard sessions (chats) with other users at any point while the user is signed in.
MSNP4 and MSNP5
MSNP3, 4, and 5 were supported by the Messenger servers by July 2000 and used by MSN Messenger 3.0 and 4.0.
MSNP6 and MSNP7
MSNP6 was used by later versions of MSN Messenger 4.x. In 2002 MSN Messenger 5.0 used MSNP7.
MSNP8
MSNP8 intr |
https://en.wikipedia.org/wiki/Glucosinolate | Glucosinolates are natural components of many pungent plants such as mustard, cabbage, and horseradish. The pungency of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damaged. These natural chemicals most likely contribute to plant defence against pests and diseases, and impart a characteristic bitter flavor property to cruciferous vegetables.
Occurrence
Glucosinolates occur as secondary metabolites of almost all plants of the order Brassicales. This includes the economically important family Brassicaceae as well as Capparaceae and Caricaceae.
Outside of the Brassicales, the genera Drypetes and Putranjiva in the family Putranjivaceae, are the only other known occurrence of glucosinolates.
Glucosinolates occur in various edible plants such as cabbage (white cabbage, Chinese cabbage, broccoli), Brussels sprouts, watercress, horseradish, capers, and radishes where the breakdown products often contribute a significant part of the distinctive taste. The glucosinolates are also found in seeds of these plants.
Chemistry
Glucosinolates constitute a natural class of organic compounds that contain sulfur and nitrogen and are derived from glucose and an amino acid.
They are water-soluble anions and belong to the glucosides. Every glucosinolate contains a central carbon atom, which is bound to the sulfur atom of the thioglucose group, and via a nitrogen atom to a sulfate group (making a sulfated aldoxime). In addition, the central carbon is bound to a side group; different glucosinolates have different side groups, and it is variation in the side group that is responsible for the variation in the biological activities of these plant compounds.
The essence of glucosinolate chemistry is their ability to convert into an isothiocyanate (a "mustard oil") upon hydrolysis of the thioglucoside bond by the enzyme myrosinase.
The semisystematic naming of glucosinolates consists of the chemical name of the group "R |
https://en.wikipedia.org/wiki/Talkback%20%28recording%29 | In sound recording, a talkback system is the intercom used in recording studios and production control rooms (PCRs) in television studios to enable personnel to communicate with people in the recording area or booth. While the control room can hear the person in the booth over the studio microphones, the person in the booth hears the control room over a PA, monitor speaker, in their headphones or interruptible feedback (IFB) earpiece. Take numbers, reference data, and sometimes count-ins or remarks are also "stamped" onto recordings through talkback, similar to a clapperboard.
The audio quality of talkback systems is usually markedly lower than that of studio microphones and speakers, coming from a simple microphone (which may be omnidirectional or unidirectional) built or plugged into the audio mixer, and with its sound often compressed. Since talkback is usually edited out of master recordings, high fidelity isn't essential, and studios tend to cut budget corners when possible. Compression allows comments from around the control room to be audible.
Occasionally instructions and comments from talkback systems do appear in studio recordings, notably in records by The Beach Boys, The Beatles, Spoon, and Bob Dylan. They frequently turn up in bootleg or "sessions" records.
Recording
Telecommunications equipment
Broadcast engineering
Television terminology |
https://en.wikipedia.org/wiki/Laboratory%20rat | Laboratory rats or lab rats are strains of the subspecies Rattus norvegicus domestica which are bred and kept for scientific research. While less commonly used for research than laboratory mice, rats have served as an important animal model for research in psychology and biomedical science.
Origins
In 18th-century Europe, wild brown rats (Rattus norvegicus) ran rampant and this infestation fueled the industry of rat-catching. Rat-catchers would not only make money by trapping the rodents, but also by selling them for food or, more commonly, for rat-baiting.
Rat-baiting was a popular sport, which involved filling a pit with rats and timing how long it took for a terrier to kill them all. Over time, breeding the rats for these contests may have produced variations in color, notably the albino and hooded varieties. The first time one of these albino mutants was brought into a laboratory for a study was in 1828 for an experiment on fasting. Over the next 30 years, rats were used for several more experiments and eventually the laboratory rat became the first animal domesticated for purely scientific reasons.
In Japan, there was a widespread practice of keeping rats as a domesticated pet during the Edo period and in the 18th century guidebooks on keeping domestic rats were published by Youso Tamanokakehashi (1775) and Chingan Sodategusa (1787). Genetic analysis of 117 albino rat strains collected from all parts of the world carried out by a team led by Takashi Kuramoto at Kyoto University in 2012 showed that the albinos descended from hooded rats and all the albinos descended from a single ancestor. As there is evidence that the hooded rat was known as the "Japanese rat" in the early 20th century, Kuramoto concluded that one or more Japanese hooded rats might have been brought to Europe or the Americas and an albino rat that emerged as a product of the breeding of these hooded rats was the common ancestor of all the albino laboratory rats in use today.
Use in resear |
https://en.wikipedia.org/wiki/Lloyd%27s%20algorithm | In electrical engineering and computer science, Lloyd's algorithm, also known as Voronoi iteration or relaxation, is an algorithm named after Stuart P. Lloyd for finding evenly spaced sets of points in subsets of Euclidean spaces and partitions of these subsets into well-shaped and uniformly sized convex cells. Like the closely related k-means clustering algorithm, it repeatedly finds the centroid of each set in the partition and then re-partitions the input according to which of these centroids is closest. In this setting, the mean operation is an integral over a region of space, and the nearest centroid operation results in Voronoi diagrams.
Although the algorithm may be applied most directly to the Euclidean plane, similar algorithms may also be applied to higher-dimensional spaces or to spaces with other non-Euclidean metrics. Lloyd's algorithm can be used to construct close approximations to centroidal Voronoi tessellations of the input, which can be used for quantization, dithering, and stippling. Other applications of Lloyd's algorithm include smoothing of triangle meshes in the finite element method.
History
The algorithm was first proposed by Stuart P. Lloyd of Bell Labs in 1957 as a technique for pulse-code modulation. Lloyd's work became widely circulated but remained unpublished until 1982. A similar algorithm was developed independently by Joel Max and published in 1960, which is why the algorithm is sometimes referred as the Lloyd-Max algorithm.
Algorithm description
Lloyd's algorithm starts by an initial placement of some number k of point sites in the input domain. In mesh-smoothing applications, these would be the vertices of the mesh to be smoothed; in other applications they may be placed at random or by intersecting a uniform triangular mesh of the appropriate size with the input domain.
It then repeatedly executes the following relaxation step:
The Voronoi diagram of the k sites is computed.
Each cell of the Voronoi diagram is integrated, |
https://en.wikipedia.org/wiki/Positive%20energy%20theorem | The positive energy theorem (also known as the positive mass theorem) refers to a collection of foundational results in general relativity and differential geometry. Its standard form, broadly speaking, asserts that the gravitational energy of an isolated system is nonnegative, and can only be zero when the system has no gravitating objects. Although these statements are often thought of as being primarily physical in nature, they can be formalized as mathematical theorems which can be proven using techniques of differential geometry, partial differential equations, and geometric measure theory.
Richard Schoen and Shing-Tung Yau, in 1979 and 1981, were the first to give proofs of the positive mass theorem. Edward Witten, in 1982, gave the outlines of an alternative proof, which were later filled in rigorously by mathematicians. Witten and Yau were awarded the Fields medal in mathematics in part for their work on this topic.
An imprecise formulation of the Schoen-Yau / Witten positive energy theorem states the following:
The meaning of these terms is discussed below. There are alternative and non-equivalent formulations for different notions of energy-momentum and for different classes of initial data sets. Not all of these formulations have been rigorously proven, and it is currently an open problem whether the above formulation holds for initial data sets of arbitrary dimension.
Historical overview
The original proof of the theorem for ADM mass was provided by Richard Schoen and Shing-Tung Yau in 1979 using variational methods and minimal surfaces. Edward Witten gave another proof in 1981 based on the use of spinors, inspired by positive energy theorems in the context of supergravity. An extension of the theorem for the Bondi mass was given by Ludvigsen and James Vickers, Gary Horowitz and Malcolm Perry, and Schoen and Yau.
Gary Gibbons, Stephen Hawking, Horowitz and Perry proved extensions of the theorem to asymptotically anti-de Sitter spacetimes and to Ei |
https://en.wikipedia.org/wiki/Elegant%20degradation | Elegant degradation is a term used in engineering to describe what occurs to machines which are subject to constant, repetitive stress.
Externally, such a machine maintains the same appearance to the user, appearing to function properly. Internally, the machine slowly weakens over time. Eventually, unable to withstand the stress, it eventually breaks down. Compared to graceful degradation, the operational quality does not decrease at all, but the breakdown may be just as sudden.
This term's meaning varies depending on context and field, and may not be strictly considered exclusive to engineering. For instance, this is used as a mechanism in the food industry as applied in the degradation of lignin, cellulose, pentosan, and polymers, among others. The concept is also used to extract chemicals such as the elegant degradation of Paederus fuscipes to obtain pederin and hemiacetal pseuodopederin. In this process degradation is induced by heat. A play with the same name also used it as a metaphor for the current state of the world.
See also
Fail safe
Fail soft |
https://en.wikipedia.org/wiki/User%20requirements%20document | The user requirement(s) document (URD) or user requirement(s) specification (URS) is a document usually used in software engineering that specifies what the user expects the software to be able to do.
Once the required information is completely gathered it is documented in a URD, which is meant to spell out exactly what the software must do and becomes part of the contractual agreement. A customer cannot demand features not in the URD, while the developer cannot claim the product is ready if it does not meet an item of the URD.
The URD can be used as a guide for planning cost, timetables, milestones, testing, etc. The explicit nature of the URD allows customers to show it to various stakeholders to make sure all necessary features are described.
Formulating a URD requires negotiation to determine what is technically and economically feasible. Preparing a URD is one of those skills that lies between a science and an art, requiring both software technical skills and interpersonal skills.
Pharmaceutical Industry Use
User Requirement Specifications (URS) are important in the pharmaceutical industry for regulatory and business purposes. URS support regulatory and business considerations for processes, equipment, and systems. For example, a business consideration could be the foot print of equipment prior to installation to ensure there is enough room. Likewise, a regulatory consideration could be the ability for the system to provide an audit trail to ensure the system meets regulatory requirements.
URS writing pitfalls
Commonly, when companies are purchasing systems, processes, and equipment - not everything is considered. URS ensure everything is considered and the supplier provides the components, features, and design required to meet the company needs. By considering more and having the components, features, and design required, the system, process, or equipment can be aligned with company interests and easily integrated.
See also
Product requirements do |
https://en.wikipedia.org/wiki/Peetre%27s%20inequality | In mathematics, Peetre's inequality, named after Jaak Peetre, says that for any real number and any vectors and in the following inequality holds:
The inequality was proved by J. Peetre in 1959 and has founds applications in functional analysis and Sobolev spaces.
See also |
https://en.wikipedia.org/wiki/Hungarian%20algorithm | The Hungarian method is a combinatorial optimization algorithm that solves the assignment problem in polynomial time and which anticipated later primal–dual methods. It was developed and published in 1955 by Harold Kuhn, who gave the name "Hungarian method" because the algorithm was largely based on the earlier works of two Hungarian mathematicians: Dénes Kőnig and Jenő Egerváry.
James Munkres reviewed the algorithm in 1957 and observed that it is (strongly) polynomial. Since then the algorithm has been known also as the Kuhn–Munkres algorithm or Munkres assignment algorithm. The time complexity of the original algorithm was , however Edmonds and Karp, and independently Tomizawa noticed that it can be modified to achieve an running time. One of the most popular variants is the Jonker–Volgenant algorithm. Ford and Fulkerson extended the method to general maximum flow problems in form of the Ford–Fulkerson algorithm. In 2006, it was discovered that Carl Gustav Jacobi had solved the assignment problem in the 19th century, and the solution had been published posthumously in 1890 in Latin.
The problem
Example
In this simple example, there are three workers: Alice, Bob and Dora. One of them has to clean the bathroom, another sweep the floors and the third washes the windows, but they each demand different pay for the various tasks. The problem is to find the lowest-cost way to assign the jobs. The problem can be represented in a matrix of the costs of the workers doing the jobs. For example:
{| class="wikitable" style="text-align:center;"
!
! Cleanbathroom
! Sweepfloors
! Wash windows
|-
! Alice
| $8
| $4
| $7
|-
! Bob
| $5
| $2
| $3
|-
! Dora
| $9
| $4
| $8
|}
The Hungarian method, when applied to the above table, would give the minimum cost: this is $15, achieved by having Alice clean the bathroom, Dora sweep the floors, and Bob wash the windows. This can be confirmed using brute force:
{| class="wikitable" style="text-align:center;"
!
! Alice
! Bob
! Dora
|-
! |
https://en.wikipedia.org/wiki/Non-orientable%20wormhole | In wormhole theory, a non-orientable wormhole is a wormhole connection that appears to reverse the chirality of anything passed through it. It is related to the "twisted" connections normally used to construct a Möbius strip or Klein bottle.
In topology, this sort of connection is referred to as an Alice handle.
Theory
"Normal" wormhole connection
Matt Visser has described a way of visualising wormhole geometry:
Take a "normal" region of space
"Surgically remove" spherical volumes from two regions ("spacetime surgery")
Associate the two spherical bleeding edges, so that a line attempting to enter one "missing" spherical volume encounters one bounding surface and then continues outward from the other.
Although these instructions seem straightforward, there are two topologically distinct ways the two surfaces can be mapped to one another. If we draw a map of the Earth's surface onto one wormhole mouth, how does this map appear at the second mouth?
For a "conventional" wormhole, the network of points will be seen at the second surface to be inverted, as if one surface was the mirror image of the other – countries will appear back-to-front, as will any text written on the map. This is as it should be, because in a sense, the second mouth is showing us the view of the same map seen "from the other side".
"Reversed" wormhole connection
The alternative way of connecting the surfaces makes the "connection map" appear the same at both mouths.
This configuration reverses the "handedness" or "chirality" of any objects passing through. If a spaceship pilot writes the word "IOTA" on the inside of their forward window, then, as the ship's nose passes through the wormhole and the ship's window intersects the surface, an observer at the other mouth looking in through the glass should see the same word, "IOTA", written on the window of the emerging spaceship. Once the spaceship has passed through, the curious onlooker may peek inside the spaceship cockpit and find tha |
https://en.wikipedia.org/wiki/Architecture%20for%20Control%20Networks | Architecture for Control Networks (ACN) is a suite of network protocols for control of entertainment technology equipment, particularly as used in live performance or large-scale installations. For example, lighting, audio or special effects equipment. ACN is maintained by Entertainment Services and Technology Association and its first official release was ANSI Standard E1.17-2006 - Entertainment Technology - Architecture for Control Networks. The standard was subsequently revised and released as ANSI E1.17-2010.
ACN was initially designed to be layered on top of UDP/IP and therefore will run over most IP transports including standard, inexpensive Ethernet and 802.11 (Wi-Fi) networks.
Protocol architecture
ACN defines a common protocol architecture, two major network protocols (SDT, DMP), a device description language (DDL) and a number of ‘E1.17 Profiles for Interoperability’ (known as EPIs or interoperability profiles) which define how elements of the ACN architecture must be used in a particular context to achieve interoperability. For example, by providing specific values or ranges for timing parameters to be used in a particular network environment.
The breakdown of ACN into sub-protocols, interoperability profiles and other small pieces has been criticized as making ACN hard to read and understand but it makes the architecture highly modular and cleanly layered and this has allowed many of the pieces to be operated in other contexts or replaced or revised without changing the other pieces. For example, DMP has been operated over TCP as well as over SDT as defined in the initial standard, DDL has been adapted with little change to describe devices accessed by DMX512 (ANSI E1.31/Streaming ACN), and several interoperability profiles have seen major revision or replacement without disturbing the other parts of the standard.
Common Architecture
The common architecture specification defines a format of nested protocol data units (PDUs), rather similar to TLV |
https://en.wikipedia.org/wiki/Astalavista.box.sk | astalavista.box.sk was founded in 1994 as one of the first search engines for computer security information. In practice it turned out to be used as a search engine for security exploits, software for hacking, cracking and different keygenerators and software cracks.
In the early 1990s and 2000s, the site was popular among people interested in hacking or securing systems against hacking. The site is known for referencing things such as spyware and viruses and because of this the website is known to possibly contain data, links, downloadable files, and information some users would consider spyware, adware, or other unwanted programs. Besides possible links to viruses, the website used to display adult adverts.
Previously, the website was part of a larger network of websites all using the box.sk domain. These websites all catered to different downloads, including MP3 music, DVD rips, and digital graphics and other hacking websites, such as New Order.
Astalavista.box.sk is hosted in Slovakia. Astalavista is a pun on the Spanish phrase "hasta la vista" (meaning "see you later"). It has been speculated that the name was a play on the 90's web search engine Altavista, however, that was launched a year later in 1995.
Astalavista.box.sk was not affiliated to astalavista.com, which was a separate hacking community, found in 1997.
On April 7, 2021, an article was published on Medium.com by Dancho Danchev stating that the site is back up and running. Subsequent attempts to reach the site however lead to a 503 Service Unavailable error on the website. |
https://en.wikipedia.org/wiki/Exception%20chaining | Exception chaining, or exception wrapping, is an object-oriented programming technique of handling exceptions by re-throwing a caught exception after wrapping it inside a new exception. The original exception is saved as a property (such as cause) of the new exception. The idea is that a method should throw exceptions defined at the same abstraction level as the method itself, but without discarding information from the lower levels.
For example, a method to play a movie file might handle exceptions in reading the file by re-throwing them inside an exception of movie playing. The user interface doesn't need to know whether the error occurred during reading chunk of bytes or calling eof(). It needs only the exception message extracted from cause. The user interface layer will have its own set of exceptions. The one interested in cause can see its stack trace during debugging or in proper log.
Throwing the right kind of exceptions is particularly enforced by checked exceptions in the Java programming language, and starting with language version 1.4 almost all exceptions support chaining.
In runtime engine environments such as Java or .NET there exist tools that attach to the runtime engine and every time that an exception of interest occurs they record debugging information that existed in memory at the time the exception was thrown (stack and heap values). These tools are called Exception Interception and they provide "root-cause" information for exceptions in Java programs that run in production, testing, or development environments. |
https://en.wikipedia.org/wiki/Chainstore%20paradox | The chainstore paradox is an apparent game theory paradox involving the chain store game, where a "deterrence strategy" appears optimal instead of the backward induction strategy of standard game theory reasoning.
The chain store game
A monopolist (Player A) has branches in 20 towns. He faces 20 potential competitors, one in each town, who will be able to choose or . They do so in sequential order and one at a time. If a potential competitor chooses , he receives a payoff of 1, while A receives a payoff of 5. If he chooses , he will receive a payoff of either 2 or 0, depending on the response of Player A to his action. Player A, in response to a choice of , must choose one of two pricing strategies, or . If he chooses , both player A and the competitor receive a payoff of 2, and if A chooses , each player receives a payoff of 0.
These outcomes lead to two theories for the game, the induction (game theoretically optimal version) and the deterrence theory (weakly dominated theory):
Induction theory
Consider the decision to be made by the 20th and final competitor, of whether to choose or . He knows that if he chooses , Player A receives a higher payoff from choosing cooperate than aggressive, and being the last period of the game, there are no longer any future competitors whom Player A needs to intimidate from the market. Knowing this, the 20th competitor enters the market, and Player A will cooperate (receiving a payoff of 2 instead of 0).
The outcome in the final period is set in stone, so to speak. Now consider period 19, and the potential competitor's decision. He knows that A will cooperate in the next period, regardless of what happens in period 19. Thus, if player 19 enters, an aggressive strategy will not be unable to deter player 20 from entering. Player 19 knows this and chooses . Player A chooses .
Of course, this process of backward induction holds all the way back to the first competitor. Each potential competitor chooses , and Player A always c |
https://en.wikipedia.org/wiki/Offset%20dish%20antenna | An offset dish antenna or off-axis dish antenna is a type of parabolic antenna. It is so called because the antenna feed is offset to the side of the reflector, in contrast to the common "front-feed" parabolic antenna where the feed antenna is suspended in front of the dish, on its axis. As in a front-fed parabolic dish, the feed is located at the focal point of the reflector, but the reflector is an asymmetric segment of a paraboloid, so the focus is located to the side.
The purpose of this design is to move the feed antenna and its supports out of the path of the incoming radio waves. In an ordinary front-fed dish antenna, the feed structure and its supports are located in the path of the incoming beam of radio waves, partially obstructing them, casting a "shadow" on the dish, reducing the radio power received. In technical terms this reduces the aperture efficiency of the antenna, reducing its gain. In the offset design, the feed is positioned outside the area of the beam, usually below it on a boom sticking out from the bottom edge of the dish. The beam axis of the antenna, the axis of the incoming or outgoing radio waves, is skewed at an angle to the plane of the dish mouth.
The design is most widely used for small parabolic antennas or "mini-dishes", such as common home satellite television dishes, where the feed structure is large enough in relation to the dish to block a significant proportion of the signal. Another application is on satellites, particularly the direct broadcast satellites which use parabolic dishes to beam television signals to homes on Earth. Because of the limited transmitter power provided by their solar cells, satellite antennas must function as efficiently as possible. The offset design is also widely used in radar antennas. These must collect as much signal as possible in order to detect faint return signals from faraway targets.
Offset dish antennas are more difficult to design than front-fed antennas because the di |
https://en.wikipedia.org/wiki/Astron%20Belt | Astron Belt (アストロンベルト) is a LaserDisc video game in the form of a third-person, space combat rail shooter, released in arcades in 1983 by Sega in Japan, and licensed to Bally Midway for release in North America. Developed in 1982, it was the first major arcade laserdisc video game. The game combines full-motion video (FMV) footage from the laserdisc with real-time 2D graphics. The arcade game was available in both upright and cockpit arcade cabinets, with the latter having illuminated buttons on the control panel, a larger 25" monitor (the upright used a standard 19"), and a force feedback vibrating seat.
The game was first unveiled at the 20th Amusement Machine Show, held in Tokyo during September 1982, and then at Chicago's Amusement & Music Operators Association (AMOA) show, held during November 18–20, 1982. This marked the beginning of laserdisc fever in the video game industry, and released in Japan during early 1983, with Sega projecting to ship 10,000 cabinets that year. It was subsequently released in Europe, where it was the first laserdisc game released in the region. However, Bally Midway delayed the game's release in the United States to fix several hardware and software bugs, by which time it had been beaten to public release by several laserdisc games including Dragon's Lair.
The game was a commercial success in arcades, especially in Japan where it was the top-grossing upright/cockpit arcade game for four months. Critical reception was initially positive following its AMOA 1982 debut and then its European release, but was later mixed following its North American release as it drew unfavorable comparisons with other laserdisc games. Astron Belt was ported to the MSX home system in 1984 in Japan.
Gameplay
The player controls a lone spacecraft on a mission to singlehandedly take down the entire enemy armada. Enemy fighters and ships shoot at the player, and there are mines and other objects that must be shot or avoided.
The game is divided into waves |
https://en.wikipedia.org/wiki/Myhill%20isomorphism%20theorem | In computability theory the Myhill isomorphism theorem, named after John Myhill, provides a characterization for two numberings to induce the same notion of computability on a set.
Theorem
Definitions
Sets A and B of natural numbers are said to be recursively isomorphic if there is a total computable bijective function f on the natural numbers such that for any , .
A set A of natural numbers is said to be one-one reducible to a set B if there is a total computable injective function f on the natural numbers such that and .
Stetement
Myhill's isomorphism theorem states that two sets A and B of natural numbers are recursively isomorphic if and only if A is one-reducible to B and B is one-reducible to A.
Corollaries
Two total numberings are one-equivalent if and only if they are recursively isomorphic.
Discussion
The theorem implies that given two injective reductions in opposing directions, there is a computable bijection on the naturals that puts the sets in question in bijective correspondence. This is reminiscent of the Schröder–Bernstein theorem about general sets, and Myhill's theorem has been called a constructive version of it.
Their proofs are however different. The proof of Schröder-Bernstein uses the inverses of the two injections, which is impossible in the setting of the Myhill theorem since these inverses might not be recursive. The proof of the Myhill theorem, on the other hand, defines the bijection inductively, which is impossible in the setting of Schröder-Bernstein unless one uses the Axiom of Choice (which is not necessary for the proof of the Myhill theorem).
See also
Berman–Hartmanis conjecture, an analogous statement in computational complexity theory |
https://en.wikipedia.org/wiki/John%20Myhill | John R. Myhill Sr. (11 August 1923 – 15 February 1987) was a British mathematician.
Education
Myhill received his Ph.D. from Harvard University under Willard Van Orman Quine in 1949. He was professor at SUNY Buffalo from 1966 until his death in 1987. He also taught at several other universities.
His son, also called John Myhill, is a professor of linguistics in the English department of the University of Haifa in Israel.
Contributions
In the theory of formal languages, the Myhill–Nerode theorem, proven by Myhill and Anil Nerode, characterizes the regular languages as the languages that have only finitely many inequivalent prefixes.
In computability theory, the Rice–Myhill–Shapiro theorem, more commonly known as Rice's theorem, states that, for any nontrivial property P of partial functions, it is undecidable to determine whether a given Turing machine computes a function with property P. The Myhill isomorphism theorem is a computability-theoretic analogue of the Cantor–Bernstein–Schroeder theorem that characterizes the recursive isomorphisms of pairs of sets.
In the theory of cellular automata, Myhill is known for proving (along with E. F. Moore) the Garden of Eden theorem, stating that a cellular automaton has a configuration with no predecessor if and only if it has two different asymptotic configurations which evolve to the same configuration. He is also known for posing the firing squad synchronization problem of designing an automaton that, starting from a single non-quiescent cell, evolves to a configuration in which all cells reach the same non-quiescent state at the same time; this problem was again solved by Moore.
In constructive set theory, Myhill is known for proposing an axiom system that avoids the axiom of choice and the law of the excluded middle, known as intuitionistic Zermelo–Fraenkel. He also developed a constructive set theory based on natural numbers, functions, and sets, rather than (as in many other foundational theories) basing it pu |
https://en.wikipedia.org/wiki/Computable%20isomorphism | In computability theory two sets of natural numbers are computably isomorphic or recursively isomorphic if there exists a total computable and bijective function such that the image of restricted to equals , i.e. .
Further, two numberings and are called computably isomorphic if there exists a computable bijection so that . Computably isomorphic numberings induce the same notion of computability on a set.
Theorems
By the Myhill isomorphism theorem, the relation of computable isomorphism coincides with the relation of mutual one-one reducibility. |
https://en.wikipedia.org/wiki/Product%20and%20manufacturing%20information | Product and manufacturing information, also abbreviated PMI, conveys non-geometric attributes in 3D computer-aided design (CAD) and Collaborative Product Development systems necessary for manufacturing product components and assemblies. PMI may include geometric dimensions and tolerances, 3D annotation (text) and dimensions, surface finish, and material specifications. PMI is used in conjunction with the 3D model within model-based definition to allow for the elimination of 2D drawings for data set utilization.
Uses and visualization
The PMI annotation is created on the 3D CAD model, associated to edges and faces, and can be exported into neutral formats such as ISO 10303 STEP and 3D PDF. This information can then be used by a number of down-stream processes. PMI can be used to generate annotation on a traditional 2D drawing the data. However, generally, PMI is used to visualized product definition within the 3D model, thus removing the need for drawings. Some 3D model formats enable computer-aided manufacturing software to access PMI directly for CNC programming. The PMI also may be used by tolerance analysis and coordinate-measuring machine (CMM) software applications if the modeling application permits.
PMI items are often organized within annotation views. Annotation views typically view including camera/view position, selected and also the particular state of the assembly (visibility, rendering mode, sometime even position of each element of the assembly). CAD applications have different notions of PMI Views (for instance "Capture Views" and "Annotation
Views" are specific to Dassault Systems CATIA, etc.).
For anyone to be able to display any kind of PMI View, Adobe Systems has unified their format and added their description to the PDF format (version 1.7).
Communication deliverables
In an effort to unify the visualization of PMI across the different existing solutions, Adobe Systems has released a version of the Myriad CAD font that allows disp |
https://en.wikipedia.org/wiki/Electron%20bubble | An electron bubble is the empty space created around a free electron in a cryogenic gas or liquid, such as neon or helium. They are typically very small, about 2 nm in diameter at atmospheric pressure.
Electron bubbles in helium
At room temperature, electrons in noble gasses move about freely, limited only by collisions with the weakly interacting atoms. Their mobility, which depends on the gas density and temperature, is well described by classical kinetic theory. As the temperature is lowered, the electron mobility decreases, since the helium atoms slow down at lower temperature and do not interact with the electron as often.
Below a critical temperature, the mobility of the electrons drops quickly to a value much below what is expected classically. This discrepancy led to the development of the electron bubble theory. At low temperatures, electrons injected into liquid helium do not move freely as one might expect, but rather form small vacuum bubbles around themselves.
Electron repulsion from the surface of helium
Electrons are attracted to liquid helium due to the difference in dielectric constants between the gas and liquid phase of helium. The negative electron polarizes the helium at the surface, leading to an image charge which binds it to the surface. The electron is forbidden from entering the liquid for the same reason hydrogen atoms are stable: quantum mechanics. The electron and image charge form a bound state, just as an electron and proton do in a hydrogen atom, with a minimum average separation. In this case, the minimum energy is about 1 eV (a moderate amount of energy on an atomic scale)[3].
When an electron is forced into liquid helium rather than floating on its surface, it forms a bubble rather than entering the liquid. The size of this bubble is determined by three main factors (ignoring small corrections): the confinement term, the surface tension term, and the pressure-volume term. The confinement term is purely quantum mech |
https://en.wikipedia.org/wiki/Apocarotenal | Apocarotenal, or trans-β-apo-8'-carotenal, is a carotenoid found in spinach and citrus fruits. Like other carotenoids, apocarotenal plays a role as a precursor of vitamin A, even though it has 50% less pro-vitamin A activity than β-carotene. The empirical chemical formula for apocarotenal is C30H40O.
Apocarotenal has an orange to orange-red colour and is used in foods, pharmaceuticals and cosmetic products. Depending on the product forms, apocarotenal is used in fat based food (margarine, sauces, salad dressing), beverages, dairy products and sweets. Its E number is E160e and it is approved for usage as a food additive in the US, EU and Australia and New Zealand.
Possible carcinogenicity
Epidemiological studies have shown that people with high β-carotene intake and high plasma levels of β-carotene have a significantly reduced risk of lung cancer. However, studies of supplementation with large doses of β-carotene in smokers have shown an increase in cancer risk, possibly because excessive β-carotene results in breakdown products that reduce plasma vitamin A and worsen the lung cell proliferation induced by smoke . The chief β-carotene breakdown product suspected of this behavior is trans-beta-apo-8'-carotenal (common apocarotenal) , which has been found in one study to be mutagenic and genotoxic in cell cultures which do not respond to β-carotene itself. |
https://en.wikipedia.org/wiki/Gilbert%20Strang | William Gilbert Strang (born November 27, 1934) is an American mathematician known for his contributions to finite element theory, the calculus of variations, wavelet analysis and linear algebra. He has made many contributions to mathematics education, including publishing mathematics textbooks. Strang was the MathWorks Professor of Mathematics at the Massachusetts Institute of Technology. He taught Linear Algebra, Computational Science, and Engineering, Learning from Data, and his lectures are freely available through MIT OpenCourseWare.
Biography
Strang was born in Chicago in 1934. His parents William and Mary Catherine Strang migrated to the USA from Scotland. He and his sister Vivian grew up in Washington DC and Cincinnati, and went to high school at Principia in St. Louis.
Strang graduated from MIT in 1955 with a Bachelor of Science in mathematics. He then received a Rhodes Scholarship to University of Oxford, where he received his B.A. and M.A. from Balliol College in 1957.
Strang earned his Ph.D. from University of California, Los Angeles in 1959 as a National Science Foundation Fellow, under the supervision of Peter K. Henrici. His dissertation was titled "Difference Methods for Mixed Boundary Value Problems".
While at Oxford, Strang met his future wife Jillian Shannon, and they married in 1958. Following his Ph.D. at UCLA, they have lived in Wellesley, Massachusetts for almost all of his 62 years on the MIT faculty. The Strangs have three sons David, John, and Robert and describe themselves as a very close-knit family. He retired on May 15, 2023 after giving his final Linear Algebra and Learning from Data lecture at MIT.
Strang's teaching has focused on linear algebra which has helped the subject become essential for students of many majors. His linear algebra video lectures are popular on YouTube and MIT OpenCourseware. Strang founded Wellesley-Cambridge Press to publish Introduction to Linear Algebra (now in 6th edition) and ten other books.
U |
https://en.wikipedia.org/wiki/Sun%20Is%20Shining%20%28Bob%20Marley%20and%20the%20Wailers%20song%29 | "Sun Is Shining" is a song by Jamaican reggae band Bob Marley & the Wailers, first appearing on the Lee Perry-produced album Soul Revolution Part II in 1971, and then on African Herbsman in 1973. Marley later re-recorded the song for his 1978 album Kaya. In 1999, a remix by "Bob Marley vs. Funkstar De Luxe" reached number one on the US Hot Dance Music/Club Play chart and number three on the UK Singles Chart.
Although having become one of the most popular Marley songs, "Sun Is Shining" used to be a fairly unknown and seldom-performed number during Marley's lifetime. Up to date, only two live performances are documented; however, both took place under special circumstances. On 16 June 1978, Marley performed at The Music Inn in Lenox, Massachusetts, a concert having been rescheduled twice since 1976, and played an over 2-hour set. "Sun Is Shining" was the opening song, reportedly included spontaneously as it stopped to rain. On 23 July 1978, Marley performed an outdoor concert at the Santa Barbara Bowl that included "Sun Is Shining" as opening song; just before the song, Marley introduced the performance by referring to Haile Selassie's birthday on the same day.
Bob Marley vs. Funkstar De Luxe version
The song was remixed in 1999 by Danish house music producer Funkstar De Luxe. It was released on the Kontor Records-sub label Club Tools, credited to Bob Marley vs. Funkstar De Luxe. The producer was the first to receive clearance from the Marley estate to release official remixes of the late singer's music (although bootleg mixes of Marley tunes have circulated in the club world for years).
The song reached number one in Iceland and on the American and Canadian dance charts, and it debuted at number three on the UK Singles Chart—Marley's highest-charting single in that country. It also became a top-10 hit in Belgium, Finland, Ireland, Norway and Switzerland.
Track listing
"Sun Is Shining" (Radio De Luxe edit) – 3:59
"Sun Is Shining" (ATB airplay mix) – 3:48
"Sun |
https://en.wikipedia.org/wiki/Messaging%20pattern | In software architecture, a messaging pattern is an architectural pattern which describes how two different parts of an application, or different systems connect and communicate with each other. There are many aspects to the concept of messaging which can be divided in the following categories: hardware device messaging (telecommunications, computer networking, IoT, etc.) and software data exchange (the different data exchange formats and software capabilities of such data exchange). Despite the difference in the context, both categories exhibit common traits for data exchange.
General concepts of the messaging pattern
In telecommunications, a message exchange pattern (MEP) describes the pattern of messages required by a communications protocol to establish or use a communication channel. The communications protocol is the format used to represent the message which all communicating parties agree on (or are capable to process). The communication channel is the infrastructure that enables messages to "travel" between the communicating parties. The message exchange patterns describe the message flow between parties in the communication process, there are two major message exchange patterns — a request–response pattern, and a one-way pattern.
For example, when viewing content on the Internet (the channel), a web browser (a communicating party) would use the HTTP (the communication protocol) to request a web page from the server (another communicating party), and then render the returned data into its visual form. This is how the request–response messaging pattern operates.
Alternatively, in computer networking, we have the UDP network protocol. It is used with the one-way messaging pattern, where the sending party is not interested whether the message arrives to any receiving party, nor it expects any of the receiving parties to produce an "answering" message.
Device communication
This section is about data exchange between hardware devices. In order for the de |
https://en.wikipedia.org/wiki/Cylinder%20set | In mathematics, the cylinder sets form a basis of the product topology on a product of sets; they are also a generating family of the cylinder σ-algebra.
General definition
Given a collection of sets, consider the Cartesian product of all sets in the collection. The canonical projection corresponding to some is the function that maps every element of the product to its component. A cylinder set is a preimage of a canonical projection or finite intersection of such preimages. Explicitly, it is a set of the form,
for any choice of , finite sequence of sets and subsets for . Here denotes the component of .
Then, when all sets in are topological spaces, the product topology is generated by cylinder sets corresponding to the components' open sets. That is cylinders of the form where for each , is open in . In the same manner, in case of measurable spaces, the cylinder σ-algebra is the one which is generated by cylinder sets corresponding to the components' measurable sets.
The restriction that the cylinder set be the intersection of a finite number of open cylinders is important; allowing infinite intersections generally results in a finer topology. In the latter case, the resulting topology is the box topology; cylinder sets are never Hilbert cubes.
Cylinder sets in products of discrete sets
Let be a finite set, containing n objects or letters. The collection of all bi-infinite strings in these letters is denoted by
The natural topology on is the discrete topology. Basic open sets in the discrete topology consist of individual letters; thus, the open cylinders of the product topology on are
The intersections of a finite number of open cylinders are the cylinder sets
Cylinder sets are clopen sets. As elements of the topology, cylinder sets are by definition open sets. The complement of an open set is a closed set, but the complement of a cylinder set is a union of cylinders, and so cylinder sets are also closed, and are thus clopen.
Definition fo |
https://en.wikipedia.org/wiki/Rootstock | A rootstock is part of a plant, often an underground part, from which new above-ground growth can be produced. It could also be described as a stem with a well developed root system, to which a bud from another plant is grafted. It can refer to a rhizome or underground stem. In grafting, it refers to a plant, sometimes just a stump, which already has an established, healthy root system, onto which a cutting or a bud from another plant is grafted. In some cases, such as vines of grapes and other berries, cuttings may be used for rootstocks, the roots being established in nursery conditions before planting them out. The plant part grafted onto the rootstock is usually called the scion. The scion is the plant that has the properties that propagator desires above ground, including the photosynthetic activity and the fruit or decorative properties. The rootstock is selected for its interaction with the soil, providing the roots and the stem to support the new plant, obtaining the necessary soil water and minerals, and resisting the relevant pests and diseases. After a few weeks, the tissues of the two parts will have grown together, eventually forming a single plant. After some years, it may be difficult to detect the site of the graft although the product always contains the components of two genetically different plants.
The use of rootstocks is most commonly associated with fruiting plants and trees, and is useful for mass propagating many other types of plants that do not breed true from seed, or are particularly susceptible to disease when grown on their own roots.
Although grafting has been practiced for many hundreds of years, even in Roman times, most orchard rootstocks in current use were developed in the 20th century.
A variety of rootstocks may be used for a single species or cultivar of scion because different rootstocks impart different properties, such as vigour, fruit size and precocity. Rootstocks also may be selected for traits such as resistance to d |
https://en.wikipedia.org/wiki/Duqqa | Duqqa, du'ah, do'a, or dukkah ( , ) is an Egyptian and Middle Eastern condiment consisting of a mixture of herbs, nuts (usually hazelnut), and spices. It is typically used as a dip with bread or fresh vegetables for an hors d'œuvre. Pre-made versions of duqqa can be bought in the spice markets of Cairo, where they are sold in paper cones, with the simplest version being crushed mint, salt, and pepper. The packaged variety that is found in markets is composed of parched wheat flour mixed with cumin and caraway. In the Hejaz region it has been part of the regional cuisine for decades.
Etymology
The word is derived from the Arabic for "to pound" since the mixture of spices and nuts is pounded together after being dry roasted to a texture that is neither powdered nor paste-like. The actual composition of the spice mix can vary from family to family, vendor to vendor though there are common ingredients, such as sesame, coriander, cumin, salt and black pepper. Reference to a 19th-century text lists marjoram, mint, zaatar and chickpeas as further ingredients that can be used in the mixture. A report from 1978 indicates that even further ingredients can be used, such as nigella, millet flour and dried cheese. Some modern variants include pine nuts, pumpkin seeds or sunflower seeds.
Internationally
Duqqa is now becoming popular in some countries outside Egypt. In the United States it has gained exposure through such TV shows as Top Chef, Chopped and Iron Chef America. In Australia, several companies now make it in a variety of flavours. It has become popular in the past ten years, probably due to recent Lebanese and Arabic immigration as well as television cooking shows such as SBS Food Network. It can be found in supermarkets, specialty stores and many farmers' markets.
See also
List of Middle Eastern dishes
List of African dishes
Charoset
Notes |
https://en.wikipedia.org/wiki/Almost%20convergent%20sequence | A bounded real sequence is said to be almost convergent to if each Banach limit assigns
the same value to the sequence .
Lorentz proved that is almost convergent if and only if
uniformly in .
The above limit can be rewritten in detail as
Almost convergence is studied in summability theory. It is an example of a summability method
which cannot be represented as a matrix method. |
https://en.wikipedia.org/wiki/Object-oriented%20analysis%20and%20design | Object-oriented analysis and design (OOAD) is a technical approach for analyzing and designing an application, system, or business by applying object-oriented programming, as well as using visual modeling throughout the software development process to guide stakeholder communication and product quality.
OOAD in modern software engineering is typically conducted in an iterative and incremental way. The outputs of OOAD activities are analysis models (for OOA) and design models (for OOD) respectively. The intention is for these to be continuously refined and evolved, driven by key factors like risks and business value.
History
In the early days of object-oriented technology before the mid-1990s, there were many different competing methodologies for software development and object-oriented modeling, often tied to specific Computer Aided Software Engineering (CASE) tool vendors. No standard notations, consistent terms and process guides were the major concerns at the time, which degraded communication efficiency and lengthened learning curves.
Some of the well-known early object-oriented methodologies were from and inspired by gurus such as Grady Booch, James Rumbaugh, Ivar Jacobson (the Three Amigos), Robert Martin, Peter Coad, Sally Shlaer, Stephen Mellor, and Rebecca Wirfs-Brock.
In 1994, the Three Amigos of Rational Software started working together to develop the Unified Modeling Language (UML). Later, together with Philippe Kruchten and Walker Royce (eldest son of Winston Royce), they have led a successful mission to merge their own methodologies, OMT, OOSE and Booch method, with various insights and experiences from other industry leaders into the Rational Unified Process (RUP), a comprehensive iterative and incremental process guide and framework for learning industry best practices of software development and project management. Since then, the Unified Process family has become probably the most popular methodology and reference model for object-oriented a |
https://en.wikipedia.org/wiki/Carprofen | Carprofen is a nonsteroidal anti-inflammatory drug (NSAID) of the carbazole and propionic acid class that was previously for use in humans and animals but is now only available to veterinarians for prescribing as a supportive treatment for various conditions in animals. Carprofen reduces inflammation by inhibition of COX-1 and COX-2; its specificity for COX-2 varies from species to species. Marketed under many brand names worldwide, carprofen is used as a treatment for inflammation and pain, including joint pain and postoperative pain.
Human use
Carprofen was used in humans for almost ten years, starting in 1988, for the same conditions as in dogs; namely, joint pain and inflammation. Side effects tended to be mild, usually consisting of nausea or gastrointestinal pain and diarrhoea. It was available by prescription in 150 mg to 600 mg doses. Dosages over 250 mg were reserved for pain caused by severe trauma, such as postoperative inflammation; 150 mg doses were commonly used to relieve arthritis pain, while 200 mg doses were commonly prescribed for severe arthritis or inflammatory pain. The drug was taken orally.
Pfizer voluntarily removed the medication from the market for human use on commercial grounds.
Veterinary medicine
Canine use
Carprofen is one of eleven nonsteroidal anti-inflammatory drugs approved for use in dogs. It aids in the relief of inflammation, pain, and fever. Carprofen can be administered in pill, chewable tablet, or injection form.
Carprofen can be used for long-term pain management of such conditions as osteoarthritis, which is common in canine patients, or after surgical procedures for relief of acute pain and inflammation.
In patients suffering from pain, carprofen has been shown to improve energy, activity level, comfort, and general well-being.
Adverse effects
Most dogs respond well to carprofen use, but like all NSAIDs, it can cause gastrointestinal, liver, and kidney problemss.
In 1999, the Food and Drug Administration (FDA) |
https://en.wikipedia.org/wiki/True%20RMS%20converter | For the measurement of an alternating current the signal is often converted into a direct current of equivalent value, the root mean square (RMS). Simple instrumentation and signal converters carry out this conversion by filtering the signal into an average rectified value and applying a correction factor. The value of the correction factor applied is only correct if the input signal is sinusoidal.
True RMS provides a more correct value that is proportional to the square root of the average of the square of the curve, and not to the average of the absolute value. For any given waveform, the ratio of these two averages is constant and, as most measurements are made on what are (nominally) sine waves, the correction factor assumes this waveform; but any distortion or offsets will lead to errors. To achieve this, a true RMS converter requires a more complex circuit.
Digital RMS converters
If a waveform has been digitized, the correct RMS value may be calculated directly. Most digital and PC-based oscilloscopes include a function to give the RMS value of a waveform. The precision and the bandwidth of the conversion is entirely dependent on the analog to digital conversion. In most cases, true RMS measurements are made on repetitive waveforms, and under such conditions digital oscilloscopes (and a few sophisticated sampling multimeters) are able to achieve very high bandwidths as they sample at much higher sampling frequency than the signal frequency to obtain a stroboscopic effect.
Thermal converters
The RMS value of an alternating current is also known as its heating value, as it is a voltage which is equivalent to the direct current value that would be required to get the same heating effect. For example, if 120 V AC RMS is applied to a resistive heating element it would heat up by exactly the same amount as if 120 V DC were applied.
This principle was exploited in early thermal converters. The AC signal would be applied to a small heating element that was matched |
https://en.wikipedia.org/wiki/Compound%20fruit | The term compound fruit is not used in technical botanical writing, but is sometimes used when it is not clear which of several fruit types is involved. A compound fruit is "composed of two or more similar parts".
A compound fruit may be:
An aggregate fruit, in which one flower contains several separate ovaries, which merge during development.
A multiple fruit, in which several flowers, each with an ovary, develop into small fruits that are clustered or fused together into a larger fruit.
A simple fruit formed from a compound ovary.
Grapes grow in clusters, but are not compound fruits. Each grape is grown from one ovary in one flower, and each grape remains an independent fruit. |
https://en.wikipedia.org/wiki/Filled%20pause | A filled pause is a non-silent pause in a otherwise fluent speech, where instead of a silent pause there is a filler. The filler can be non-lexical or semiarticulate utterances such as huh, uh, erm, um, and hmm, and, in English, well, so, I mean, and like.
This particular type of pause is one of several types of speech disfluencies, which also includes silent pauses, "false starts", phrases that are restarted or repeated, and repeated syllables.
External links
Oral communication
Speech and language pathology
Linguistics
Human communication |
https://en.wikipedia.org/wiki/The%20Business%20Cloud | The Business Cloud is an API enabled self-service platform, developed by Domo, that provides an array of services like data connection and data visualization.
History
Domo, Inc. was founded in 2010 by Josh James who also co-founded the web analytics software company Omniture in 1996, which he took public in 2006.
Domo launched the Domo Appstore, with a 1000 apps with social and mobile capabilities, in 2016. This appstore creates a network of business apps and an ecosystem of companies into a single, integrated business cloud. This decision came after Domo announced a $131 million round of funding from BlackRock.
According to the company, the concept behind The Business Cloud is to connect smaller clouds relating to apps or other functional areas of a business into a single business cloud that allows self-service and other social features to customers.
Services
The Business Cloud is offered as a free service, claimed to be the world's first business cloud with Domo appstore as one of its core services. This free package includes all of the Domo's features and functionality including Domo platform, Domo Apps, visualizations, alerts, company directories, org charts, profiles, tasks and Domo Mobile. The Business Cloud allows customers to leverage their preferred cloud as well as on-premises software and monitor all aspects of their business in routine.
The company is supported by a $500 million fund from investors all over the world. |
https://en.wikipedia.org/wiki/MasPar | MasPar Computer Corporation was a minisupercomputer vendor that was founded in 1987 by Jeff Kalb. The company was based in Sunnyvale, California.
History
While Kalb was the vice-president of the division of Digital Equipment Corporation (DEC) that built integrated circuits, some researchers in that division were building a supercomputer based on the Goodyear MPP (massively parallel processor) supercomputer. The DEC researchers enhanced the architecture by:
making the processor elements to be 4-bit instead of 1-bit
increasing the connectivity of each processor element to 8 neighbors from 4.
adding a global interconnect for all of the processing elements, which was a triple-redundant switch which was easier to implement than a full crossbar switch.
After Digital decided not to commercialize the research project, Kalb decided to start a company to sell this minisupercomputer. In 1990, the first generation product MP-1 was delivered. In 1992, the follow-on MP-2 was shipped. The company shipped more than 200 systems.
MasPar along with nCUBE criticized the open government support, by DARPA, of competitors Intel for their hypercube Personal SuperComputers (iPSC) and the Thinking Machines Connection Machine on the pages of Datamation.
Samples of MasPar MPs, from the NASA Goddard Space Flight Center, are in storage at the Computer History Museum.
MasPar offered a family of SIMD machines, second sourced by DEC. The processor units are proprietary.
There was no MP-3. MasPar exited the computer hardware business in June 1996, halting all hardware development and transforming itself into a new data mining software company called NeoVista Software. NeoVista was acquired by Accrue Software in 1999, which in turn sold the division to JDA Software in 2001.
Hardware
MasPar is unique in being a manufacturer of SIMD supercomputers (as opposed to vector machines). In this approach, a collection of ALU's listen to a program broadcast from a central source. The ALUs can do t |
https://en.wikipedia.org/wiki/Animal%20Genome%20Size%20Database | The Animal Genome Size Database is a catalogue of published genome size estimates for vertebrate and invertebrate animals. It was created in 2001 by Dr. T. Ryan Gregory of the University of Guelph in Canada. As of September 2005, the database contains data for over 4,000 species of animals. A similar database, the Plant DNA C-values Database (C-value being analogous to genome size in diploid organisms) was created by researchers at the Royal Botanic Gardens, Kew, in 1997.
See also
List of organisms by chromosome count |
https://en.wikipedia.org/wiki/Omega%20network | An Omega network is a network configuration often used in parallel computing architectures. It is an indirect topology that relies on the perfect shuffle interconnection algorithm.
Connection architecture
An 8x8 Omega network is a multistage interconnection network, meaning that processing elements (PEs) are connected using multiple stages of switches. Inputs and outputs are given addresses as shown in the figure. The outputs from each stage are connected to the inputs of the next stage using a perfect shuffle connection system. This means that the connections at each stage represent the movement of a deck of cards divided into 2 equal decks and then shuffled together, with each card from one deck alternating with the corresponding card from the other deck. In terms of binary representation of the PEs, each stage of the perfect shuffle can be thought of as a cyclic logical left shift; each bit in the address is shifted once to the left, with the most significant bit moving to the least significant bit.
At each stage, adjacent pairs of inputs are connected to a simple exchange element, which can be set either straight (pass inputs directly through to outputs) or crossed (send top input to bottom output, and vice versa). For N processing element, an Omega network contains N/2 switches at each stage, and log2N stages. The manner in which these switches are set determines the connection paths available in the network at any given time. Two such methods are destination-tag routing and XOR-tag routing, discussed in detail below.
The Omega Network is highly blocking, though one path can always be made from any input to any output in a free network.
Destination-tag routing
In destination-tag routing, switch settings are determined solely by the message destination. The most significant bit of the destination address is used to select the output of the switch in the first stage; if the most significant bit is 0, the upper output is selected, and if it is 1, the lower out |
https://en.wikipedia.org/wiki/Metachromasia | Metachromasia (var. metachromasy) is a characteristical change in the color of staining carried out in biological tissues, exhibited by certain dyes when they bind to particular substances present in these tissues, called chromotropes. For example, toluidine blue becomes dark blue (with a colour range from blue-red dependent on glycosaminoglycan content) when bound to cartilage. Other widely used metachromatic stains are the haematological Giemsa and May-Grunwald stains that also contain thiazine dyes. The white cell nucleus stains purple, basophil granules intense magenta, whilst the cytoplasms (of mononuclear cells) stains blue. The absence of color change in staining is named orthochromasia.
The underlying mechanism for metachromasia requires the presence of polyanions within the tissue. When these tissues are stained with a concentrated basic dye solution, such as toluidine blue, the bound dye molecules are close enough to form dimeric and polymeric aggregates. The light absorption spectra of these stacked dye aggregates differ from those of the individual monomeric dye molecules. Cell and tissue structures that have high concentrations of ionized sulfate and phosphate groups—such as the ground substance of cartilage, heparin-containing granules of mast cells, and rough endoplasmic reticulum of plasma cells—exhibit metachromasia. This depends on the charge density of the negative sulfate and carboxylate anions in the glycosaminoglycan (GAG). The GAG polyanion stabilizes the stacked, positively-charged dye molecules, resulting in a spectral shift as the conjugated double bond π-orbitals of adjacent dye molecules overlap. The greater the degree of stacking, the greater the metachromatic shift. Thus, hyaluronic acid, lacking sulphate groups and with only moderate charge density, causes slight metachromasia; chondroitin sulfate, with an additional sulfate residue per GAG saccharide dimer, is an effective metachromatic substrate, whilst heparin, with further N- |
https://en.wikipedia.org/wiki/Plant%20DNA%20C-values%20Database | The Plant DNA C-values Database (https://cvalues.science.kew.org/) is a comprehensive catalogue of C-value (nuclear DNA content, or in diploids, genome size) data for land plants and algae. The database was created by Prof. Michael D. Bennett and Dr. Ilia J. Leitch of the Royal Botanic Gardens, Kew, UK. The database was originally launched as the "Angiosperm DNA C-values Database" in April 1997, essentially as an online version of collected data lists that had been published by Prof. Bennett and colleagues since the 1970s. Release 1.0 of the more inclusive Plant DNA C-values Database was launched in 2001, with subsequent releases 2.0 in January 2003 and 3.0 in December 2004. In addition to the angiosperm dataset made available in 1997, the database has been expanded taxonomically several times and now includes data from pteridophytes (since 2000), gymnosperms (since 2001), bryophytes (since 2001), and algae (since 2004) (see (1) for update history). (Note that each of these subset databases is cited individually as they may contain different sets of authors).
The most recent release of the database (release 7.1) went live in April 2019. It contains data for 12,273 species of plants comprising 10,770 angiosperms, 421 gymnosperms, 303 pteridophytes (246 ferns and fern allies and 57 lycophytes), 334 bryophytes, and 445 algae.
A similar Animal Genome Size Database was created in 2001 by Dr. T. Ryan Gregory of the University of Guelph, Canada. |
https://en.wikipedia.org/wiki/Pole%20figure | A pole figure is a graphical representation of the orientation of objects in space. For example, pole figures in the form of stereographic projections are used to represent the orientation distribution of crystallographic lattice planes in crystallography and texture analysis in materials science.
Definition
Consider an object with a basis attached to it. The orientation of the object in space can be determined by three rotations to transform the reference basis of space to the basis attached to the object; these are the Euler angles.
If we consider a plane of the object, the orientation of the plane can be given by its normal line. If we draw a sphere with the center on the plane, then
the intersection of the sphere and the plane is a circle, called the "trace" ;
the intersection of the normal line and the sphere is the pole.
A single pole is not enough to fully determine the orientation of an object: the pole stays the same if we apply a rotation around the normal line. The orientation of the object is fully determined by the use of poles of two planes that are not parallel.
Stereographic projection
The upper sphere is projected on a plane using the stereographic projection.
Consider the (x,y) plane of the reference basis; its trace on the sphere is the equator of the sphere. We draw a line joining the South pole with the pole of interest P.
It is possible to choose any projection plane parallel to the equator (except the South pole): the figures will be proportional (property of similar triangles). It is usual to place the projection plane at the North pole.
Definition
The pole figure is the stereographic projection of the poles used to represent the orientation of an object in space.
Geometry in the pole figure
A Wulff net is used to read a pole figure.
The stereographic projection of a trace is an arc. The Wulff net is arcs corresponding to planes that share a common axis in the (x,y) plane.
If the pole and the trace of a plane are represented |
https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93Woods%20number | In number theory, a positive integer is said to be an Erdős–Woods number if it has the following property:
there exists a positive integer such that in the sequence of consecutive integers, each of the elements has a non-trivial common factor with one of the endpoints. In other words, is an Erdős–Woods number if there exists a positive integer such that for each integer between and , at least one of the greatest common divisors or is greater than .
Examples
The first Erdős–Woods numbers are
16, 22, 34, 36, 46, 56, 64, 66, 70, 76, 78, 86, 88, 92, 94, 96, 100, 106, 112, 116 … .
History
Investigation of such numbers stemmed from the following prior conjecture by Paul Erdős:
There exists a positive integer such that every integer is uniquely determined by the list of prime divisors of .
Alan R. Woods investigated this question for his 1981 thesis. Woods conjectured that whenever , the interval always includes a number coprime to both endpoints. It was only later that he found the first counterexample, , with . The existence of this counterexample shows that 16 is an Erdős–Woods number.
proved that there are infinitely many Erdős–Woods numbers, and showed that the set of Erdős–Woods numbers is recursive. |
https://en.wikipedia.org/wiki/F-term | In theoretical physics, one often analyzes theories with supersymmetry in which F-terms play an important role. In four dimensions, the minimal N=1 supersymmetry may be written using a superspace. This superspace involves four extra fermionic coordinates , transforming as a two-component spinor and its conjugate.
Every superfield—i.e. a field that depends on all coordinates of the superspace—may be expanded with respect to the new fermionic coordinates. There exists a special kind of superfields, the so-called chiral superfields, that only depend on the variables but not their conjugates. The last term in the corresponding expansion, namely , is called the F-term. Applying an infinitesimal supersymmetry transformation to a chiral superfield results in yet another chiral superfield whose F-term, in particular, changes by a total derivative. This is significant because then is invariant under SUSY transformations as long as boundary terms vanish. Thus F-terms may be used in constructing supersymmetric actions.
Manifestly-supersymmetric Lagrangians may also be written as integrals over the whole superspace. Some special terms, such as the superpotential, may be written as integrals over s only. They are also referred to as F-terms, much like the terms in the ordinary potential that arise from these terms of the supersymmetric Lagrangian.
See also
D-term
Supersymmetric gauge theory
Supersymmetric quantum field theory |
https://en.wikipedia.org/wiki/D-term | In theoretical physics, one often analyzes theories with supersymmetry in which D-terms play an important role. In four dimensions, the minimal N=1 supersymmetry may be written using a superspace. This superspace involves four extra fermionic coordinates , transforming as a two-component spinor and its conjugate.
Every superfield, i.e. a field that depends on all coordinates of the superspace, may be expanded with respect to the new fermionic coordinates. The generic kind of superfields, typically a vector superfield, indeed depend on all these coordinates. The last term in the corresponding expansion, namely , is called the D-term.
Manifestly supersymmetric Lagrangians may also be written as integrals over the whole superspace. Some special terms, such as the superpotential, may be written as integrals over s only, which are known as F-terms, and should be contrasted with the present D-terms.
See also
F-term
Supersymmetric gauge theory
Supersymmetric quantum field theory |
https://en.wikipedia.org/wiki/Supersymmetric%20gauge%20theory | In theoretical physics, there are many theories with supersymmetry (SUSY) which also have internal gauge symmetries. Supersymmetric gauge theory generalizes this notion.
Gauge theory
A gauge theory is a field theory with gauge symmetry. Roughly, there are two types of symmetries, global and local. A global symmetry is a symmetry applied uniformly (in some sense) to each point of a manifold. A local symmetry is a symmetry which is position dependent. Gauge symmetry is an example of a local symmetry, with the symmetry described by a Lie group (which mathematically describe continuous symmetries), which in the context of gauge theory is called the gauge group of the theory.
Quantum chromodynamics and quantum electrodynamics are famous examples of gauge theories.
Supersymmetry
In particle physics, there exist particles with two kinds of particle statistics, bosons and fermions. Bosons carry integer spin values, and are characterized by the ability to have any number of identical bosons occupy a single point in space. They are thus identified with forces. Fermions carry half-integer spin values, and by the Pauli exclusion principle, identical fermions cannot occupy a single position in spacetime. Boson and fermion fields are interpreted as matter. Thus, supersymmetry is considered a strong candidate for the unification of radiation (boson-mediated forces) and matter.
This unification is given by an operator (or typically many operators), known as a supercharge or supersymmetry generator, which acts schematically as
For instance, the supersymmetry generator can take a photon as an argument and transform it into a photino and vice versa. This happens through translation in the (parameter) space. This superspace is a -graded vector space , where is the bosonic Hilbert space and is the fermionic Hilbert space.
SUSY gauge theory
The motivation for a supersymmetric version of gauge theory can be the fact that gauge invariance is consistent with supersymmetry.
Th |
https://en.wikipedia.org/wiki/Montonen%E2%80%93Olive%20duality | Montonen–Olive duality or electric–magnetic duality is the oldest known example of strong–weak duality or S-duality according to current terminology. It generalizes the electro-magnetic symmetry of Maxwell's equations by stating that magnetic monopoles, which are usually viewed as emergent quasiparticles that are "composite" (i.e. they are solitons or topological defects), can in fact be viewed as "elementary" quantized particles with electrons playing the reverse role of "composite" topological solitons; the viewpoints are equivalent and the situation dependent on the duality. It was later proven to hold true when dealing with a N = 4 supersymmetric Yang–Mills theory. It is named after Finnish physicist Claus Montonen and British physicist David Olive after they proposed the idea in their academic paper Magnetic monopoles as gauge particles? where they state:
S-duality is now a basic ingredient in topological quantum field theories and string theories, especially since the 1990s with the advent of the second superstring revolution. This duality is now one of several in string theory, the AdS/CFT correspondence which gives rise to the holographic principle, being viewed as amongst the most important. These dualities have played an important role in condensed matter physics, from predicting fractional charges of the electron, to the discovery of the magnetic monopole.
Electric–magnetic duality
The idea of a close similarity between electricity and magnetism, going back to the time of André-Marie Ampère and Michael Faraday, was first made more precise with James Clerk Maxwell's formulation of his famous equations for a unified theory of electric and magnetic fields:
The symmetry between and in these equations is striking. If one ignores the sources, or adds magnetic sources, the equations are invariant under and .
Why should there be such symmetry between and ? In 1931 Paul Dirac was studying the quantum mechanics of an electric charge moving in a magnetic |
https://en.wikipedia.org/wiki/Flavor-changing%20neutral%20current | In particle physics, flavor-changing neutral currents or flavour-changing neutral currents (FCNCs) are hypothetical interactions that change the flavor of a fermion without altering its electric charge.
Details
If they occur in nature (as reflected by Lagrangian interaction terms), these processes may induce phenomena that have not yet been observed in experiment. Flavor-changing neutral currents may occur in the Standard Model beyond the tree level, but they are highly suppressed by the GIM mechanism. Several collaborations have searched for FCNC. The Tevatron CDF experiment observed evidence of FCNC in the decay of the strange B-meson to phi mesons in 2005.
FCNCs are generically predicted by theories that attempt to go beyond the Standard Model, such as the models of supersymmetry or technicolor. Their suppression is necessary for an agreement with observations, making FCNCs important constraints on model-building.
Example
Consider a toy model in which an undiscovered boson S may couple both to the electron as well as the tau () via the term
Since the electron and the tau have equal charges, the electric charge of S clearly must vanish to respect the conservation of electric charge. A Feynman diagram with S as the intermediate particle is able to convert a tau into an electron (plus some neutral decay products of the S).
The MEG experiment at the Paul Scherrer Institute near Zurich will search for a similar process, in which an antimuon decays to a photon and an antielectron (a positron). In the Standard Model, such a process proceeds only by emission and re-absorption of a charged , which changes the into a neutrino on emission and then a positron on re-absorption, and finally emits a photon that carries away any difference in energy, spin, and momentum.
In most cases of interest, the boson involved is not a new boson S but the conventional boson itself. This can occur if the coupling to weak neutral currents is (slightly) non-universal. The dominant uni |
https://en.wikipedia.org/wiki/Nielsen%E2%80%93Olesen%20string | In theoretical physics, Nielsen–Olesen string is a one-dimensional object or equivalently a classical solution of certain equations of motion. The solution does not depend on the direction along the string; the dependence on the other two, transverse dimensions is identical as in the case of a Nielsen–Olesen vortex.
Quantum field theory |
https://en.wikipedia.org/wiki/Nielsen%E2%80%93Olesen%20vortex | In theoretical physics, a Nielsen–Olesen vortex is a point-like object localized in two spatial dimensions or, equivalently, a classical solution of field theory with the same property. This particular solution occurs if the configuration space of scalar fields contains non-contractible circles. A circle surrounding the vortex at infinity may be "wrapped" once on the other circle in the configuration space. A configuration with this non-trivial topological property is called the Nielsen–Olesen vortex, after Holger Bech Nielsen and Poul Olesen (1973). The solution is formally identical to the solution of Quantum vortex in superconductor.
See also
Nielsen–Olsen string
Abrikosov vortex
Montonen–Olive duality
S-duality |
https://en.wikipedia.org/wiki/Particle%20zoo | In particle physics, the term particle zoo is used colloquially to describe the relatively extensive list of known subatomic particles by comparison to the variety of species in a zoo.
In the history of particle physics, the topic of particles was considered to be particularly confusing in the late 1960s. Before the discovery of quarks, hundreds of strongly interacting particles (hadrons) were known and believed to be distinct elementary particles. It was later discovered that they were not elementary particles, but rather composites of quarks. The set of particles believed today to be elementary is known as the Standard Model and includes quarks, bosons and leptons.
The term "subnuclear zoo" was coined or popularized by Robert Oppenheimer in 1956 at the VI Rochester International Conference on High Energy Physics.
See also
Eightfold way (physics)
List of mesons
List of baryons
List of particles |
https://en.wikipedia.org/wiki/Ultraviolet%20completion | In theoretical physics, ultraviolet completion, or UV completion, of a quantum field theory is the passing from a lower energy quantum field theory to a more general quantum field theory above a threshold value known as the cutoff. In particular, the more general high energy theory must be well-defined at arbitrarily high energies.
The word "ultraviolet" in this so-called "ultraviolet regime" is only figurative, and refers to energies much higher than ultraviolet light per se. Rather, by analogy to the relationship between ultraviolet and visible light, it refers to energies higher than (and wavelengths shorter than) those "visible" to laboratory experiment.
The ultraviolet theory must be renormalizable; it can have no Landau poles; and most typically, it enjoys asymptotic freedom in the case that it is a quantum field theory (or at least has a nontrivial fixed point). However, it may also be a background of string theory whose ultraviolet behavior is at least as good as that of renormalizable quantum field theories. Besides these two known examples (QFT and string theory), it could be a completely different theory than string theory that behaves well at very high energies.
There is an analogous phrase "infrared completion", which applies to length scales longer than those "visible" to normal experiment, particularly cosmology distances.
See also
Ultraviolet divergence
Fermi's interaction
Quantum mechanics
String theory
Quantum field theory
Renormalization group |
https://en.wikipedia.org/wiki/Robert%20Ulanowicz | Robert Edward Ulanowicz ( ) is an American theoretical ecologist and philosopher of Polish descent who in his search for a unified theory of ecology has formulated a paradigm he calls Process Ecology. He was born September 17, 1943, in Baltimore, Maryland.
He served as professor of theoretical ecology at the University of Maryland Center for Environmental Science's Chesapeake Biological Laboratory in Solomons, Maryland, until his retirement in 2008. Ulanowicz received both his BS and PhD in chemical engineering from Johns Hopkins University in 1964 and 1968, respectively.
Ulanowicz currently resides in Gainesville, Florida, where he holds a courtesy professorship in the Department of Biology at the University of Florida. Since relocating to Florida, Ulanowicz has served as a scientific advisor to the Howard T. Odum Florida Springs Institute, an organization dedicated to the preservation and welfare of Florida's natural springs.
Overview
Ulanowicz uses techniques from information theory and thermodynamics to study the organization of flows of energy and nutrients within ecosystems. Although his ideas have been primarily applied in ecology, many of his concepts are abstract and have been applied to other areas in which flow networks arise, such as psychology and economics.
Though Ulanowicz began his career modeling ecological systems using differential equations, he soon reached the limits of this approach. Realizing that any ecosystem is a complex system, he decided to move away from what he saw as the inappropriate use of the reductionist approach, and instead began to work towards development of theoretical measures of the ecosystem as a whole, such as ascendency. Gradually, he came to appreciate the ecosystem behavior is not simply a matter of "mechanics with noise," but rather an intricate interplay between opposing tendencies—autocatalytic-like self-organization and entropic decay. This natural conversation could be followed quantitatively using informatio |
https://en.wikipedia.org/wiki/Charcuterie | Charcuterie ( , also ; ; from , and ) is a French term for a branch of cooking devoted to prepared meat products, such as bacon, ham, sausage, terrines, galantines, ballotines, pâtés, and confit, primarily from pork.
Charcuterie is part of the garde manger chef's repertoire. Originally intended as a way to preserve meat before the advent of refrigeration, they are prepared today for their flavors derived from the preservation processes.
Terminology
The French word for a person who practices charcuterie is . The etymology of the word is the combination of chair and cuite, or cooked flesh. The Herbsts in Food Lover's Companion say, "it refers to the products, particularly (but not limited to) pork specialties such as , etc., which are made and sold in a delicatessen-style shop, also called a charcuterie." Montagné in his 1938 edition of Larousse Gastronomique defines it as "[t]he art of preparing various meats, in particular pork, in order to present them in the most diverse ways."
Products created with forcemeats
Forcemeat
Forcemeat is a mixture of ground, lean meat emulsified with fat. The emulsification can be accomplished by grinding, sieving, or puréeing the ingredients. The emulsification may either be smooth or coarse in texture, depending on the desired consistency of the final product. Forcemeats are used in the production of numerous items found in charcuterie. Meats commonly used in the production of forcemeats include pork, fish (pike, trout, or salmon), seafood, game meats (venison, boar, or rabbit), poultry, game birds, veal, and pork livers. Pork fatback is often used for the fat portion of forcemeat, as it has a somewhat neutral flavor.
In US usage, there are four basic styles of forcemeat. Straight forcemeats are produced by progressively grinding equal parts pork and pork fat with a third dominant meat which can be pork or another meat. The proteins are cubed and then seasoned, cured, rested, ground and then placed into the desired vess |
https://en.wikipedia.org/wiki/MotoMagx | MotoMagx was a Linux kernel-based mobile operating system developed and launched in 2007 by Motorola to run on their mid-to-high-end mobile phones. The system was based on MontaVista's Mobilinux. Originally intended for 60% of their upcoming devices, it was soon dropped in favor of Android and Windows Mobile operating systems.
MOTOMAGX was only compatible with Motorola's GSM/UMTS devices (as shown below). This was due to the lack of an implementation compatible with Qualcomm CDMA2000 devices. As a result, Motorola often sold multiple device variants with radically different firmware. For example, the Motorola RAZR2 on T-Mobile shipped with MOTOMAGX, whereas the RAZR2 on Verizon Wireless shipped with Motorola's P2k firmware.
This created significant confusion for customers, as the user experience varied widely between two otherwise identical devices, simply based on which carrier they were on.
Devices
Phones based on this OS are:
Motorola EM30
Motorola ROKR E2
Motorola ROKR E8
Motorola ROKR/RIZR Z6
Motorola U9
Motorola RAZR2 V8
Motorola VE66
Motorola ZINE ZN5
Motorola Tundra V76r
Motorola ROKR EM35
Motorola ROKR ZN200 |
https://en.wikipedia.org/wiki/Yuja%20tea | Yuja-cha () or yuja tea is a traditional Korean tea made by mixing hot water with yuja-cheong (yuja marmalade). Yuja tea is popular throughout Korea, especially in the winter. This tea is created by curing yuja into a sweet, thick, pulpy syrup. It does not contain caffeine. It is often sold in markets in large jars and used as a home remedy for the common cold.
Yuja tea is made from the yuja fruit, which is commonly known outside of Korea as yuzu. Yuja does not contain much juice, unlike other citrus fruits. They are able to cook in high temperatures without losing their tartness. Yuja have a strong fragrance. Their scent comes from the zest, juices, and essential oils. Yuja tea is bittersweet. In addition, yuja tea is a preservative, so it can be left out on a shelf or counter.
History
A man was carrying a shipment of yuja trees from China to Korea until a storm came and hit his boat. The yuja trees were destroyed, but some of the seeds went into the man's coat. As the man continued on Korea's soil, the seeds fell on the ground and grew into yuja trees. Koreans saw the benefits the leaves had and used the yuja leaves for the common cold by crushing it. Because of its bitter taste, they began to preserve the leaves in sugar and honey, which later developed into the yuja tea. King Sejong, who was responsible for the creation of the Korean Hangul script, was its greatest advocate.
Names
Occasionally, the term yuja-cha can also be used to refer to the jarred yuja marmalade used to make the tea. The drink's name is sometimes translated into "citron tea" or "honey citron tea" in English, but yuja and citron are different citrus fruits. In Sinophone regions, the tea is referred to as "", but the word in Chinese refers to pomelo, not yuja. The word "" is a result of direct translation from the tea's Korean name.
Benefits
Yuja tea is well known for its health benefits, albeit medically unproven. It is said to have more vitamin C (2.3 times more) than raw lemon juice |
https://en.wikipedia.org/wiki/G-LOC | g-force induced loss of consciousness (abbreviated as G-LOC, pronounced "JEE-lock") is a term generally used in aerospace physiology to describe a loss of consciousness occurring from excessive and sustained g-forces draining blood away from the brain causing cerebral hypoxia. The condition is most likely to affect pilots of high performance fighter and aerobatic aircraft or astronauts but is possible on some extreme amusement park rides. G-LOC incidents have caused fatal accidents in high performance aircraft capable of sustaining high g for extended periods. High-g training for pilots of high performance aircraft or spacecraft often includes ground training for G-LOC in special centrifuges, with some profiles exposing pilots to 9 gs for a sustained period.
Effects of g-forces
Under increasing positive g-force, blood in the body will tend to move from the head toward the feet. For higher intensity or longer duration, this can manifest progressively as:
Tunnel vision – loss of peripheral vision, retaining only the center vision
Greyout – a loss of color vision
Blackout – a complete loss of vision but retaining consciousness.
G-LOC – where consciousness is lost.
Under negative g, blood pressure will increase in the head, running the risk of the dangerous condition known as redout, with too much blood pressure in the head and eyes.
Because of the high level of sensitivity that the eye’s retina has to hypoxia, symptoms are usually first experienced visually. As the retinal blood pressure decreases below Intraocular pressure (usually 10–21 mm Hg), blood flow begins to cease to the retina, first affecting perfusion farthest from the optic disc and central retinal artery with progression towards central vision. Skilled pilots can use this loss of vision as their indicator that they are at maximum turn performance without losing consciousness. Recovery is usually prompt following removal of g-force but a period of several seconds of disorientation may occur. Ab |
https://en.wikipedia.org/wiki/Inheritance%20%28object-oriented%20programming%29 | In object-oriented programming, inheritance is the mechanism of basing an object or class upon another object (prototype-based inheritance) or class (class-based inheritance), retaining similar implementation. Also defined as deriving new classes (sub classes) from existing ones such as super class or base class and then forming them into a hierarchy of classes. In most class-based object-oriented languages like C++, an object created through inheritance, a "child object", acquires all the properties and behaviors of the "parent object", with the exception of: constructors, destructors, overloaded operators and friend functions of the base class. Inheritance allows programmers to create classes that are built upon existing classes, to specify a new implementation while maintaining the same behaviors (realizing an interface), to reuse code and to independently extend original software via public classes and interfaces. The relationships of objects or classes through inheritance give rise to a directed acyclic graph.
An inherited class is called a subclass of its parent class or super class. The term "inheritance" is loosely used for both class-based and prototype-based programming, but in narrow use the term is reserved for class-based programming (one class inherits from another), with the corresponding technique in prototype-based programming being instead called delegation (one object delegates to another). Class-modifying inheritance patterns can be pre-defined according to simple network interface parameters such that inter-language compatibility is preserved.
Inheritance should not be confused with subtyping. In some languages inheritance and subtyping agree, whereas in others they differ; in general, subtyping establishes an is-a relationship, whereas inheritance only reuses implementation and establishes a syntactic relationship, not necessarily a semantic relationship (inheritance does not ensure behavioral subtyping). To distinguish these concepts, subtyp |
https://en.wikipedia.org/wiki/AMD%20FirePro | AMD FirePro was AMD's brand of graphics cards designed for use in workstations and servers running professional Computer-aided design (CAD), Computer-generated imagery (CGI), Digital content creation (DCC), and High-performance computing/GPGPU applications. The GPU chips on FirePro-branded graphics cards are identical to the ones used on Radeon-branded graphics cards. The end products (i.e. the graphics card) differentiate substantially by the provided graphics device drivers and through the available professional support for the software. The product line is split into two categories: "W" workstation series focusing on workstation and primarily focusing on graphics and display, and "S" server series focused on virtualization and GPGPU/High-performance computing.
The release of the Radeon Pro Duo in April 2016 and the announcement of the Radeon Pro WX Series in July 2016 marked the succession of Radeon Pro as AMD's professional workstation graphics card solution. Radeon Instinct is the current brand for servers.
Competitors included Nvidia's Quadro-branded and to an extent, Nvidia Tesla-branded product series and Intel's Xeon Phi-branded products.
History
The FireGL line was originally developed by the German company Spea Software AG until it was acquired by Diamond Multimedia in November 1995. The first FireGL board used the 3Dlabs GLINT 3D processor chip.
Deprecated brand names are ATI FireGL, ATI FirePro 3D, and AMD FireStream.
In July 2016, AMD announced it would be replacing the FirePro brand with Radeon Pro for workstations. The new brand for servers is Radeon Instinct.
Features
Multi-monitor support
AMD Eyefinity can support multi-monitor set-ups. One graphics card can drive up to a maximum of six monitors; the supported number depends on the distinct product and the number of DisplayPort displays. The device driver facilitates the configuration of diverse display group modes.
Differences with the Radeon Line
The FirePro line is designed for comput |
https://en.wikipedia.org/wiki/Valve%20Anti-Cheat | Valve Anti-Cheat (VAC) is an anti-cheat tool developed by Valve as a component of the Steam platform, first released with Counter-Strike in 2002.
When the software detects a cheat on a player's system, it will ban them in the future, possibly days or weeks after the original detection. It may kick players from the game if it detects errors in their system's memory or hardware. No information such as date of detection or type of cheat detected is disclosed to the player. After the player is notified, access to online "VAC protected" servers of the game the player cheated in is permanently revoked and additional restrictions are applied to the player's Steam account.
During one week of November 2006, the system detected over 10,000 cheating attempts.
During the month of December 2018 over 600,000 accounts were banned.
History
In 2001, Even Balance Inc., the developers of the anti-cheat software PunkBuster designed for Counter-Strike and Half-Life mods, stopped supporting the games as they had no support from Valve. Valve had also rejected business offers of integrating the technology directly into their games.
Valve started working on a "long-term solution" for cheating in 2001. VAC's initial release was with Counter-Strike in 2002. During this initial release, the system only banned players for 24 hours. The duration of the ban was increased over time; players were banned for 1 year and 5 years, until VAC2 was released in 2005, when any new bans became permanent. VAC2 was announced in February 2005 and began beta testing the following month. On November 17, 2006, they announced that "new [VAC] technology" had caught "over 10,000" cheating attempts in the preceding week alone.
During the early testing phase in 2002, some information was revealed about the program via the Half-Life Dedicated Server mailing lists. It can detect versions of "OGC's OpenGl Hack", can detect OpenGL cheats, and also detects CD key changers as cheats. Information on detected cheaters is |
https://en.wikipedia.org/wiki/Gravitational%20instanton | In mathematical physics and differential geometry, a gravitational instanton is a four-dimensional complete Riemannian manifold satisfying the vacuum Einstein equations. They are so named because they are analogues in quantum theories of gravity of instantons in Yang–Mills theory. In accordance with this analogy with self-dual Yang–Mills instantons, gravitational instantons are usually assumed to look like four dimensional Euclidean space at large distances, and to have a self-dual Riemann tensor. Mathematically, this means that they are asymptotically locally Euclidean (or perhaps asymptotically locally flat) hyperkähler 4-manifolds, and in this sense, they are special examples of Einstein manifolds. From a physical point of view, a gravitational instanton is a non-singular solution of the vacuum Einstein equations with positive-definite, as opposed to Lorentzian, metric.
There are many possible generalizations of the original conception of a gravitational instanton: for example one can allow gravitational instantons to have a nonzero cosmological constant or a Riemann tensor which is not self-dual. One can also relax the boundary condition that the metric is asymptotically Euclidean.
There are many methods for constructing gravitational instantons, including the Gibbons–Hawking Ansatz, twistor theory, and the hyperkähler quotient construction.
Introduction
Gravitational instantons are interesting, as they offer insights into the quantization of gravity. For example, positive definite asymptotically locally Euclidean metrics are needed as they obey the positive-action conjecture; actions that are unbounded below create divergence in the quantum path integral.
A four-dimensional Kähler–Einstein manifold has a self-dual Riemann tensor.
Equivalently, a self-dual gravitational instanton is a four-dimensional complete hyperkähler manifold.
Gravitational instantons are analogous to self-dual Yang–Mills instantons.
Several distinctions can be made with respect to |
https://en.wikipedia.org/wiki/Job%20Submission%20Description%20Language | Job Submission Description Language is an extensible XML specification from the Global Grid Forum for the description of simple tasks to non-interactive computer execution systems. Currently at version 1.0 (released November 7, 2005), the specification focuses on the description of computational task submissions to traditional high-performance computer systems like batch schedulers.
Description
JSDL describes the submission aspects of a job, and does not attempt to describe the state of running or historic jobs. Instead, JSDL includes descriptions of:
Job name, description
Resource requirements that computers must have to be eligible for scheduling, such as total RAM available, total swap available, CPU clock speed, number of CPUs, Operating System, etc.
Execution limits, such as the maximum amount of CPU time, wallclock time, or memory that can be consumed.
File staging, or the transferring of files before or after execution.
Command to execute, including its command-line arguments, environment variables to define, stdin/stdout/stderr redirection, etc.
Software support
The following software is known to currently support JSDL:
GridWay meta scheduler
Platform LSF 7
UNICORE 6
GridSAM
Windows HPC Server 2008
GRIA
Genesis II Project http://genesis2.virginia.edu/wiki/
Advanced Resource Connector (ARC v0.6 and above)
XtreemOS Grid Operating System
EMOTIVE Cloud
IBM Tivoli Workload Scheduler Tivoli Workload Scheduler
See also
Resource Specification Language (See The Globus Resource Specification Language RSL v1.0)
Distributed Resource Management Application API
External links
JSDL working group project page
Windows HPC Server 2008
Grid computing
XML-based standards
Computer-related introductions in 2005 |
https://en.wikipedia.org/wiki/Conformal%20Killing%20vector%20field | In conformal geometry, a conformal Killing vector field on a manifold of dimension n with (pseudo) Riemannian metric (also called a conformal Killing vector, CKV, or conformal colineation), is a vector field whose (locally defined) flow defines conformal transformations, that is, preserve up to scale and preserve the conformal structure. Several equivalent formulations, called the conformal Killing equation, exist in terms of the Lie derivative of the flow e.g.
for some function on the manifold. For there are a finite number of solutions, specifying the conformal symmetry of that space, but in two dimensions, there is an infinity of solutions. The name Killing refers to Wilhelm Killing, who first investigated Killing vector fields.
Densitized metric tensor and Conformal Killing vectors
A vector field is a Killing vector field if and only if its flow preserves the metric tensor (strictly speaking for each compact subsets of the manifold, the flow need only be defined for finite time). Formulated mathematically, is Killing if and only if it satisfies
where is the Lie derivative.
More generally, define a w-Killing vector field as a vector field whose (local) flow preserves the densitized metric , where is the volume density defined by (i.e. locally ) and is its weight. Note that a Killing vector field preserves and so automatically also satisfies this more general equation. Also note that is the unique weight that makes the combination invariant under scaling of the metric. Therefore, in this case, the condition depends only on the conformal structure.
Now is a w-Killing vector field if and only if
Since this is equivalent to
Taking traces of both sides, we conclude . Hence for , necessarily and a w-Killing vector field is just a normal Killing vector field whose flow preserves the metric. However, for , the flow of has to only preserve the conformal structure and is, by definition, a conformal Killing vector field.
Equivalent formul |
https://en.wikipedia.org/wiki/MCS%20algorithm | For mathematical optimization, Multilevel Coordinate Search (MCS) is an efficient algorithm for bound constrained global optimization using function values only.
To do so, the n-dimensional search space is represented by a set of non-intersecting hypercubes (boxes). The boxes are then iteratively split along an axis plane according to the value of the function at a representative point of the box (and its neighbours) and the box's size. These two splitting criteria combine to form a global search by splitting large boxes and a local search by splitting areas for which the function value is good.
Additionally, a local search combining a (multi-dimensional) quadratic interpolant of the function and line searches can be used to augment performance of the algorithm (MCS with local search); in this case the plain MCS is used to provide the starting (initial) points. The information provided by local searches (local minima of the objective function) is then fed back to the optimizer and affects the splitting criteria, resulting in reduced sample clustering around local minima, faster convergence and higher precision.
Simplified workflow
The MCS workflow is visualized in Figures 1 and 2. Each step of the algorithm can be split into four stages:
Identify a potential candidate for splitting (magenta, thick).
Identify the optimal splitting direction and the expected optimal position of the splitting point (green).
Evaluate the objective function at the splitting point or recover it from the already computed set; the latter applies if the current splitting point has already been reached when splitting a neighboring box.
Generate new boxes (magenta, thin) based on the values of the objective function at the splitting point.
At each step the green point with the temporary yellow halo is the unique base point of the box; each box has an associated value of the objective, namely its value at the box's base point.
In order to determine if a box will be split two separat |
https://en.wikipedia.org/wiki/Ionic%20strength | The ionic strength of a solution is a measure of the concentration of ions in that solution. Ionic compounds, when dissolved in water, dissociate into ions. The total electrolyte concentration in solution will affect important properties such as the dissociation constant or the solubility of different salts. One of the main characteristics of a solution with dissolved ions is the ionic strength. Ionic strength can be molar (mol/L solution) or molal (mol/kg solvent) and to avoid confusion the units should be stated explicitly. The concept of ionic strength was first introduced by Lewis and Randall in 1921 while describing the activity coefficients of strong electrolytes.
Quantifying ionic strength
The molar ionic strength, I, of a solution is a function of the concentration of all ions present in that solution.
where one half is because we are including both cations and anions, ci is the molar concentration of ion i (M, mol/L), zi is the charge number of that ion, and the sum is taken over all ions in the solution. For a 1:1 electrolyte such as sodium chloride, where each ion is singly-charged, the ionic strength is equal to the concentration. For the electrolyte MgSO4, however, each ion is doubly-charged, leading to an ionic strength that is four times higher than an equivalent concentration of sodium chloride:
Generally multivalent ions contribute strongly to the ionic strength.
Calculation example
As a more complex example, the ionic strength of a mixed solution 0.050 M in Na2SO4 and 0.020 M in KCl is:
Non-ideal solutions
Because in non-ideal solutions volumes are no longer strictly additive it is often preferable to work with molality b (mol/kg of H2O) rather than molarity c (mol/L). In that case, molal ionic strength is defined as:
in which
i = ion identification number
z = charge of ion
b = molality (mol solute per Kg solvent)
Importance
The ionic strength plays a central role in the Debye–Hückel theory that describes the strong deviations from id |
https://en.wikipedia.org/wiki/BRST%20algorithm | Boender-Rinnooy-Stougie-Timmer algorithm (BRST) is an optimization algorithm suitable for finding global optimum of black box functions. In their paper Boender et al. describe their method as a stochastic method involving a combination of sampling, clustering and local search, terminating with a range of confidence intervals on the value of the global minimum.
The algorithm of Boender et al. has been modified by Timmer. Timmer considered several clustering methods. Based on experiments a method named "multi level single linkage" was deemed most accurate.
Csendes' algorithms are implementations of the algorithm of [Boender et al.] and originated the public domain software product GLOBAL. The local algorithms used are a random direction, linear search algorithm also used by Törn, and a quasi—Newton algorithm not using the derivative of the function. The results show the dependence of the result on the auxiliary local algorithm used.
Background
Extending the class of functions to include multimodal functions makes the global optimization problem unsolvable in general. In order to be solvable some smoothness condition on the function in addition to continuity must be known.
The existence of several local minima and unsolvability in general are important characteristics of global optimization. Unsolvability here means that a solution cannot be guaranteed in a finite number of steps.
There are two ways to deal with the unsolvability problem. First, "a priori" conditions on f and A are posed which turns the problem into a solvable one or at least makes it possible to tell for sure that a solution has been found. This restricts the function class that is considered.
The second approach which allows a larger class of objective functions to be considered is to give up the solvability requirement and only try to obtain an estimate of the global minimum. In this "probabilistic" approach it would be desirable also to obtain some results on the goodness of an obtained esti |
https://en.wikipedia.org/wiki/Flow%20%28mathematics%29 | In mathematics, a flow formalizes the idea of the motion of particles in a fluid. Flows are ubiquitous in science, including engineering and physics. The notion of flow is basic to the study of ordinary differential equations. Informally, a flow may be viewed as a continuous motion of points over time. More formally, a flow is a group action of the real numbers on a set.
The idea of a vector flow, that is, the flow determined by a vector field, occurs in the areas of differential topology, Riemannian geometry and Lie groups. Specific examples of vector flows include the geodesic flow, the Hamiltonian flow, the Ricci flow, the mean curvature flow, and Anosov flows. Flows may also be defined for systems of random variables and stochastic processes, and occur in the study of ergodic dynamical systems. The most celebrated of these is perhaps the Bernoulli flow.
Formal definition
A flow on a set is a group action of the additive group of real numbers on . More explicitly, a flow is a mapping
such that, for all and all real numbers and ,
It is customary to write instead of , so that the equations above can be expressed as (the identity function) and (group law). Then, for all the mapping is a bijection with inverse This follows from the above definition, and the real parameter may be taken as a generalized functional power, as in function iteration.
Flows are usually required to be compatible with structures furnished on the set . In particular, if is equipped with a topology, then is usually required to be continuous. If is equipped with a differentiable structure, then is usually required to be differentiable. In these cases the flow forms a one-parameter group of homeomorphisms and diffeomorphisms, respectively.
In certain situations one might also consider s, which are defined only in some subset
called the of . This is often the case with the flows of vector fields.
Alternative notations
It is very common in many fields, including engi |
https://en.wikipedia.org/wiki/Vector%20flow | In mathematics, the vector flow refers to a set of closely related concepts of the flow determined by a vector field. These appear in a number of different contexts, including differential topology, Riemannian geometry and Lie group theory. These related concepts are explored in a spectrum of articles:
exponential map (Riemannian geometry)
matrix exponential
exponential function
infinitesimal generator (→ Lie group)
integral curve (→ vector field)
one-parameter subgroup
flow (geometry)
geodesic flow
Hamiltonian flow
Ricci flow
Anosov flow
injectivity radius (→ glossary)
Vector flow in differential topology
Relevant concepts: (flow, infinitesimal generator, integral curve, complete vector field)
Let V be a smooth vector field on a smooth manifold M. There is a unique maximal flow D → M whose infinitesimal generator is V. Here D ⊆ R × M is the flow domain. For each p ∈ M the map Dp → M is the unique maximal integral curve of V starting at p.
A global flow is one whose flow domain is all of R × M. Global flows define smooth actions of R on M. A vector field is complete if it generates a global flow. Every smooth vector field on a compact manifold without boundary is complete.
Vector flow in Riemannian geometry
Relevant concepts: (geodesic, exponential map, injectivity radius)
The exponential map
exp : TpM → M
is defined as exp(X) = γ(1) where γ : I → M is the unique geodesic passing through p at 0 and whose tangent vector at 0 is X. Here I is the maximal open interval of R for which the geodesic is defined.
Let M be a pseudo-Riemannian manifold (or any manifold with an affine connection) and let p be a point in M. Then for every V in TpM there exists a unique geodesic γ : I → M for which γ(0) = p and Let Dp be the subset of TpM for which 1 lies in I.
Vector flow in Lie group theory
Relevant concepts: (exponential map, infinitesimal generator, one-parameter group)
Every left-invariant vector field on a Lie group is complete. The integral curve starting a |
https://en.wikipedia.org/wiki/Legendre%27s%20conjecture | Legendre's conjecture, proposed by Adrien-Marie Legendre, states that there is a prime number between and for every positive integer . The conjecture is one of Landau's problems (1912) on prime numbers; , the conjecture has neither been proved nor disproved.
Prime gaps
If Legendre's conjecture is true, the gap between any prime p and the next largest prime would be , as expressed in big O notation. It is one of a family of results and conjectures related to prime gaps, that is, to the spacing between prime numbers. Others include Bertrand's postulate, on the existence of a prime between and , Oppermann's conjecture on the existence of primes between , , and , Andrica's conjecture and Brocard's conjecture on the existence of primes between squares of consecutive primes, and Cramér's conjecture that the gaps are always much smaller, of the order . If Cramér's conjecture is true, Legendre's conjecture would follow for all sufficiently large n. Harald Cramér also proved that the Riemann hypothesis implies a weaker bound of on the size of the largest prime gaps.
By the prime number theorem, the expected number of primes between and is approximately , and it is additionally known that for almost all intervals of this form the actual number of primes () is asymptotic to this expected number. Since this number is large for large , this lends credence to Legendre's conjecture. It is known that the prime number theorem gives an accurate count of the primes within short intervals, either unconditionally or based on the Riemann hypothesis, but the lengths of the intervals for which this has been proven are longer than the intervals between consecutive squares, too long to prove Legendre's conjecture.
Partial results
It follows from a result by Ingham that for all sufficiently large , there is a prime between the consecutive cubes and .
Baker, Harman and Pintz proved that there is a prime in the interval for all large .
A table of maximal prime gaps shows that the |
https://en.wikipedia.org/wiki/Carry%20On%2C%20Mr.%20Bowditch | Carry On, Mr. Bowditch is a novel by Jean Lee Latham that was awarded the Newbery Medal in 1956.
The book is a children's biography of Nathaniel Bowditch, a sailor and mathematician who published the mammoth and comprehensive reference work for seamen: The American Practical Navigator. It is an epic tale of adventure and learning.
Plot summary
In Revolutionary War–era Salem, Massachusetts, a young Nat Bowditch, the smallest member of a sea-faring family, astounds his schoolteacher with his talent for mathematics. He dreams of someday attending Harvard University but is forced by his family's financial hardships to quit school and work in his father's cooperage. Even that sacrifice is not enough, and his family contracts him into indentured servitude at a chandlery. Determined to continue his education, he uses his nine years as a clerk to teach himself subjects such as trigonometry, calculus, Latin, and French.
Upon the fulfillment of his servitude, he takes a job as a surveyor, which quickly evolves into a career as an officer and supercargo on various merchant ships. Numerous voyages take him to ports around the world and sometime into brushes with the wars being fought by the newly founded United States. In his duties as a navigator, he discovers that many of the references available contain dangerous errors, and he is compelled to compile a new book of navigational data. His experiences educating crew members serving under him allow Nat to supplement his numeric tables with information that allow sailors with limited educations to learn the trade of navigation. Eventually Nat becomes a captain and faces his greatest navigational challenge of all.
Reception
Kirkus Reviews called the book "A readable biography of the man who was scarcely out of his teens before he had written the authoritative book on navigation still used at Annapolis". In a retrospective essay about the Newbery Medal-winning books from 1956 to 1965, librarian Carolyn Horovitz wrote of Carr |
https://en.wikipedia.org/wiki/Unconditional%20convergence | In mathematics, specifically functional analysis, a series is unconditionally convergent if all reorderings of the series converge to the same value. In contrast, a series is conditionally convergent if it converges but different orderings do not all converge to that same value. Unconditional convergence is equivalent to absolute convergence in finite-dimensional vector spaces, but is a weaker property in infinite dimensions.
Definition
Let be a topological vector space. Let be an index set and for all
The series is called unconditionally convergent to if
the indexing set is countable, and
for every permutation (bijection) of the following relation holds:
Alternative definition
Unconditional convergence is often defined in an equivalent way: A series is unconditionally convergent if for every sequence with the series
converges.
If is a Banach space, every absolutely convergent series is unconditionally convergent, but the converse implication does not hold in general. Indeed, if is an infinite-dimensional Banach space, then by Dvoretzky–Rogers theorem there always exists an unconditionally convergent series in this space that is not absolutely convergent. However when by the Riemann series theorem, the series is unconditionally convergent if and only if it is absolutely convergent.
See also |
https://en.wikipedia.org/wiki/Brocard%27s%20conjecture | In number theory, Brocard's conjecture is the conjecture that there are at least four prime numbers between (pn)2 and (pn+1)2, where pn is the nth prime number, for every n ≥ 2. The conjecture is named after Henri Brocard. It is widely believed that this conjecture is true. However, it remains unproven as of 2022.
The number of primes between prime squares is 2, 5, 6, 15, 9, 22, 11, 27, ... .
Legendre's conjecture that there is a prime between consecutive integer squares directly implies that there are at least two primes between prime squares for pn ≥ 3 since pn+1 − pn ≥ 2.
See also
Prime-counting function
Notes
Conjectures about prime numbers
Unsolved problems in number theory
Squares in number theory |
https://en.wikipedia.org/wiki/Emblems%20of%20the%20International%20Red%20Cross%20and%20Red%20Crescent%20Movement | The emblems of the International Red Cross and Red Crescent Movement, under the Geneva Conventions, are to be placed on humanitarian and medical vehicles and buildings, and to be worn by medical personnel and others carrying out humanitarian work, to protect them from military attack on the battlefield. There are four such emblems, three of which are in use: the Red Cross, the Red Crescent, and the Red Crystal. The Red Lion and Sun is also a recognized emblem, but is no longer in use.
There were also prior disputes concerning the use of a Red Star of David by Magen David Adom (MDA), the Israeli first-aid society; the Red Crystal was created in response to these disputes, thus enabling the admission of MDA to the movement.
In popular culture, the red cross symbol came to be a recognizable generic emblem for medicine, commonly associated with first aid, medical services, products, or professionals; it has been unlawfully used in toys, movies, and video games, outside its defined context. After objections from the International Red Cross and Red Crescent Movement, derivatives and alternatives have come to be used instead. Additionally, Johnson & Johnson has registered the symbol for their medicinal products. The appropriation of the symbol has led to further irritation due to the practice of hospitals, first aid teams, and ski patrols in the United States reversing the symbol to a white cross on a red background – so undoing the original idea of the Red Cross emblem, namely reversing the Swiss flag – thus inappropriately suggesting an affiliation with Switzerland.
Symbols of the movement
Protection symbols vs. organizational emblems
The symbols described below have two distinctively different meanings. On one hand, the visual symbols of the Red Cross, the Red Crescent, the Red Lion with Sun and the Red Crystal serve as protection markings in armed conflicts, a denotation which is derived from and defined in the Geneva Conventions. This is called the protective use |
https://en.wikipedia.org/wiki/Lone%20Star%20Toys | Lone Star Products Ltd. was the brand name used by the British company Die Cast Machine Tools Ltd (DCMT) for its toy products. DCMT was based in Welham Green, Hertfordshire, north of London.
Company history
Starting as early as 1939, DCMT manufactured die cast toys for children. The 'Lone Star' name was chosen because of a demand at the time for toy guns and rifles popular in the Western films in cinemas all over Britain. Eventually, the company also made tie-in toy guns licensed from the James Bond films and The Man From U.N.C.L.E. TV series.
Toy soldiers
Harry Eagles, one of the sons of Henry George Eagles who co-founded Crescent Toys had been known by the nickname of Harvey. When Crescent moved to South Wales in 1949, Eagles remained in London where he started the Harvey Toy Company, producing figures in hollowcast metal. Eagles sold his trade name and designs to Lone Star where a variety of plastic soldiers were sold from 1955 to 1976,
Vehicles
Competition with Dinky and Corgi
Interpreting the base of a Lone Star vehicle can be difficult. Some of Impy Toys read: "Lone Star Road-Master Impy Super Cars".
To keep up with competitors such as Corgi and Dinky, Lone Star began producing Corgi-sized diecast toy vehicles in 1956 with its Road-Master series (later spelled without the hyphen). Castings on the earlier vehicles, though handsome, were a bit cruder than the competition. For example, the double-deck bus had its casting line, for its two halves, right down the centre of the roof. Also, most earlier Lone Stars have simpler bumper, grille and body detail than Corgi or Dinky.
The Impy Series
Much changed with the introduction of the Impy line in 1966. Bright new packaging was introduced while the older, larger, Road-Master series was discontinued (though the name "Roadmaster" was still used). The new cars were a smaller three and a half inch size, similar to Mini-Dinkys, and were advertised as the "cars with everything". For example, the 1963 Chrysler Imper |
https://en.wikipedia.org/wiki/Birkeland%20current | A Birkeland current (also known as field-aligned current) is a set of electrical currents that flow along geomagnetic field lines connecting the Earth's magnetosphere to the Earth's high latitude ionosphere. In the Earth's magnetosphere, the currents are driven by the solar wind and interplanetary magnetic field and by bulk motions of plasma through the magnetosphere (convection indirectly driven by the interplanetary environment). The strength of the Birkeland currents changes with activity in the magnetosphere (e.g. during substorms). Small scale variations in the upward current sheets (downward flowing electrons) accelerate magnetospheric electrons which, when they reach the upper atmosphere, create the Auroras Borealis and Australis. In the high latitude ionosphere (or auroral zones), the Birkeland currents close through the region of the auroral electrojet, which flows perpendicular to the local magnetic field in the ionosphere. The Birkeland currents occur in two pairs of field-aligned current sheets. One pair extends from noon through the dusk sector to the midnight sector. The other pair extends from noon through the dawn sector to the midnight sector. The sheet on the high latitude side of the auroral zone is referred to as the Region 1 current sheet and the sheet on the low latitude side is referred to as the Region 2 current sheet.
The currents were predicted in 1908 by Norwegian explorer and physicist Kristian Birkeland, who undertook expeditions north of the Arctic Circle to study the aurora. He rediscovered, using simple magnetic field measurement instruments, that when the aurora appeared the needles of magnetometers changed direction, confirming the findings of Anders Celsius and assistant Olof Hjorter more than a century before. This could only imply that currents were flowing in the atmosphere above. He theorized that somehow the Sun emitted a cathode ray, and corpuscles from what is now known as a solar wind entered the Earth's magnetic field and |
https://en.wikipedia.org/wiki/Crystal%20Ball%20function | The Crystal Ball function, named after the Crystal Ball Collaboration (hence the capitalized initial letters), is a probability density function commonly used to model various lossy processes in high-energy physics. It consists of a Gaussian core portion and a power-law low-end tail, below a certain threshold. The function itself and its first derivative are both continuous.
The Crystal Ball function is given by:
where
,
,
,
,
.
(Skwarnicki 1986) is a normalization factor and , , and are parameters which are fitted with the data. erf is the error function.
External links
J. E. Gaiser, Appendix-F Charmonium Spectroscopy from Radiative Decays of the J/Psi and Psi-Prime, Ph.D. Thesis, SLAC-R-255 (1982). (This is a 205-page document in .pdf form – the function is defined on p. 178.)
M. J. Oreglia, A Study of the Reactions psi prime --> gamma gamma psi, Ph.D. Thesis, SLAC-R-236 (1980), Appendix D.
T. Skwarnicki, A study of the radiative CASCADE transitions between the Upsilon-Prime and Upsilon resonances, Ph.D Thesis, DESY F31-86-02(1986), Appendix E.
Functions and mappings
Continuous distributions
Experimental particle physics |
https://en.wikipedia.org/wiki/Shaping%20%28psychology%29 | Shaping is a conditioning paradigm used primarily in the experimental analysis of behavior. The method used is differential reinforcement of successive approximations. It was introduced by B. F. Skinner with pigeons and extended to dogs, dolphins, humans and other species. In shaping, the form of an existing response is gradually changed across successive trials towards a desired target behavior by reinforcing exact segments of behavior. Skinner's explanation of shaping was this:
Successive approximations
The successive approximations reinforced are increasingly closer approximations of the target behavior set by the trainer. As training progresses the trainer stops reinforcing the less accurate approximations. When the trainer stops reinforcing this behavior, the learner will go through an extinction burst in which they perform many behaviors in an attempt to receive that reinforcement. The trainer will pick one of those behaviors that is a closer approximation to the target behavior and reinforce that chosen behavior. The trainer repeats this process with the successive approximations getting closer to the target response until the learner achieves the intended behavior.
For example, to train a rat to press a lever, the following successive approximations might be applied:
simply turning toward the lever will be reinforced
only moving toward the lever will be reinforced
only moving to within a specified distance from the lever will be reinforced
only touching the lever with any part of the body, such as the nose, will be reinforced
only touching the lever with a specified paw will be reinforced
only depressing the lever partially with the specified paw will be reinforced
only depressing the lever completely with the specified paw will be reinforced
The trainer starts by reinforcing all behaviors in the first category, here turning toward the lever. When the animal regularly performs that response (turning), the trainer restricts reinforcement to respons |
https://en.wikipedia.org/wiki/Theil%20index | The Theil index is a statistic primarily used to measure economic inequality and other economic phenomena, though it has also been used to measure racial segregation.
The Theil index TT is the same as redundancy in information theory which is the maximum possible entropy of the data minus the observed entropy. It is a special case of the generalized entropy index. It can be viewed as a measure of redundancy, lack of diversity, isolation, segregation, inequality, non-randomness, and compressibility. It was proposed by a Dutch econometrician Henri Theil (1924-2000) at the Erasmus University Rotterdam.
Henri Theil himself said (1967): "The (Theil) index can be interpreted as the expected information content of the indirect message which transforms the population shares as prior probabilities into the income shares as posterior probabilities."
Amartya Sen noted, "But the fact remains that the Theil index is an arbitrary formula, and the average of the logarithms of the reciprocals of income shares weighted by income is not a measure that is exactly overflowing with intuitive sense."
Formula
For a population of N "agents" each with characteristic x, the situation may be represented by the list xi (i = 1,...,N) where xi is the characteristic of agent i. For example, if the characteristic is income, then xi is the income of agent i.
The Theil T index is defined as
and the Theil L index is defined as
where is the mean income:
Theil-L is an income-distribution's dis-entropy per person, measured with respect to maximum entropy (...which is achieved with complete equality).
(In an alternative interpretation of it, Theil-L is the natural-logarithm of the geometric-mean of the ratio: (mean income)/(income i), over all the incomes. The related Atkinson(1) is just 1 minus the geometric-mean of (income i)/(mean income),over the income distribution.)
Because a transfer between a larger income & a smaller one will change the smaller income's ratio more than it chan |
https://en.wikipedia.org/wiki/Relative%20risk | The relative risk (RR) or risk ratio is the ratio of the probability of an outcome in an exposed group to the probability of an outcome in an unexposed group. Together with risk difference and odds ratio, relative risk measures the association between the exposure and the outcome.
Statistical use and meaning
Relative risk is used in the statistical analysis of the data of ecological, cohort, medical and intervention studies, to estimate the strength of the association between exposures (treatments or risk factors) and outcomes. Mathematically, it is the incidence rate of the outcome in the exposed group, , divided by the rate of the unexposed group, . As such, it is used to compare the risk of an adverse outcome when receiving a medical treatment versus no treatment (or placebo), or for environmental risk factors. For example, in a study examining the effect of the drug apixaban on the occurrence of thromboembolism, 8.8% of placebo-treated patients experienced the disease, but only 1.7% of patients treated with the drug did, so the relative risk is .19 (1.7/8.8): patients receiving apixaban had 19% the disease risk of patients receiving the placebo. In this case, apixaban is a protective factor rather than a risk factor, because it reduces the risk of disease.
Assuming the causal effect between the exposure and the outcome, values of relative risk can be interpreted as follows:
RR = 1 means that exposure does not affect the outcome
RR < 1 means that the risk of the outcome is decreased by the exposure, which is a "protective factor"
RR > 1 means that the risk of the outcome is increased by the exposure, which is a "risk factor"
As always, correlation does not mean causation; the causation could be reversed, or they could both be caused by a common confounding variable. The relative risk of having cancer when in the hospital versus at home, for example, would be greater than 1, but that is because having cancer causes people to go to the hospital.
Usage in r |
https://en.wikipedia.org/wiki/Radisys | Radisys Corporation is an American technology company located in Hillsboro, Oregon, United States that makes technology used by telecommunications companies in mobile networks. Founded in 1987 in Oregon by former employees of Intel, the company went public in 1995. The company's products are used in mobile network applications such as small cell radio access networks, wireless core network elements, deep packet inspection and policy management equipment; conferencing, and media services including voice, video and data. In 2015, the first-quarter revenues of Radisys totaled $48.7 million, and approximately employed 700 people. Arun Bhikshesvaran is the company's chief executive officer.
On 30 June 2018, multinational conglomerate Reliance Industries acquired Radisys for $74 million.
It now operates as an independent subsidiary.
History
Radisys was founded in 1987 as Radix Microsystems in Beaverton, Oregon, by former Intel engineers Dave Budde and Glen Myers. The first investors were employees who put up $50,000 each, with Tektronix later investing additional funds into the company. Originally located in space leased from Sequent Computer Systems, by 1994 the company had grown to annual sales of $20 million. The company's products were computers used in end products such as automated teller machines to paint mixers. On October 20, 1995, the company became a publicly traded company when it held an initial public offering (IPO). The IPO raised $19.6 million for Radisys after selling 2.7 million shares at $12 per share.
In 1996, the company moved its headquarters to a new campus in Hillsboro, and at that time sales reached $80 million and the company had a profit of $9.6 million that year with 175 employees. Company co-founder Dave Budde left the company in 1997, with company revenues at $81 million annually at that time. The company grew in part by acquisitions such as Sonitech International in 1997, part of IBM's Open Computing Platform unit and Texas Micro in 1999 |
https://en.wikipedia.org/wiki/Alan%20Beddoe | Lieutenant-Commander Alan Brookman Beddoe, OC, OBE, HFHS, FHSC (June 1, 1893 – December 2, 1975) was a Canadian artist, war artist, consultant in heraldry and founder and first president of the Heraldry Society of Canada in 1965.
Born in Ottawa, Ontario, in 1893, he studied at Ashbury College. During World War I, he was captured at Second Battle of Ypres in 1915 and spent two and a half years in the prisoner of war camps at Gießen and Zerbst. He studied art at the Ecole des Beaux-Arts in Paris. After the war, he studied at the Art Students League of New York under DuMond and Bridgman. In 1925, he opened the first commercial art studio in Ottawa. He was also an expert in heraldry. The Alan Beddoe collection at Library and Archives Canada contains designs and studies for the Book of Remembrance, postage stamps, posters, crests, money, architecture, coats-of-arms, and a new Canadian flag. His fonds include slides, colour transparencies, prints, watercolours and drawings related to Canadian heraldry.
Books of Remembrance
Beddoe was instrumental in the creation of the major Books of Remembrance, now housed in the Peace Tower on Parliament Hill in Ottawa. The artist originally chosen for the job, James Purves, died in 1940, at which time Beddoe took on the task. He supervised a team of artists for about the next 2 years to illuminate and hand-letter the books, listing the names of Canadians who died in Canada's military service during World War I and after World War II he supervised another team of artists to create the Book of Remembrance for World War II. He was inducted to the OBE and received the Allied Arts Medal awarded by the Royal Architectural Institute for his work on the Books of Remembrance and made an officer of the Order of Canada. He also was instrumental in the creation of the South Africa Book of Remembrance 1956–1966; Yvonne Diceman, who had worked with him on the Book of Remembrance WWII, produced the Korea Book of Remembrance 1957–1958 and the Ne |
https://en.wikipedia.org/wiki/Palestine%20Park | Palestine Park is a scale model of the Holy Land, including cities, hills, rivers, and seas, in approximately correct geographical relation on the grounds of Chautauqua Institution in Chautauqua, New York. Palestine Park is laid out along the southwestern side of Chautauqua Lake, which takes the place of the Mediterranean Sea. This creates a rotated version of the actual land, which is on the east coast of the Mediterranean. A large mound of stones represents Mount Hermon, with an artificial stream representing the Jordan River as it flows south from the Sea of Galilee to the Dead Sea. Small hills represent biblical landmarks such as Mount Tabor and the Mount of Olives, with markers representing sites of biblical significance including Jacob's Well, Jericho, Bethsaida and a scale model of Jerusalem in the time of Jesus complete with a small replica of the ancient Jewish Temple.
The park was one of Chautauqua's first landmarks. In 1874, Chautauqua founder Rev. John Heyl Vincent gave his friend Dr. W. W. Wythe the task of laying out Palestine Park as a visual aid for teaching Biblical history and geography to the Sunday School teachers that were Chautauqua's first visitors. In the nineteenth century, people arrived at Chautauqua via ferryboats and disembarked at Palestine Park so that their first footsteps were on the Holy Land as though they were pilgrims going up to Jerusalem; an actual journey to the Land of Israel was well beyond the financial ability of most Americans in that era.
The park has been reconstructed many times over the years. The present Palestine Park is 350 feet long with a scale of to . The park is a contributing property in the Chautauqua Institution Historic District.
There are educational guided tours through the park each Sunday and Monday at 7 p.m. (weather permitting) during Chautauqua's nine-week summer season. |
https://en.wikipedia.org/wiki/Artificial%20plants | Artificial plants are imitations of natural plants used for commercial or residential decoration. They are sometimes made for scientific purposes (the collection of glass flowers at Harvard University, for example, illustrates the flora of the United States). Artificial plants vary widely from mass-produced varieties that are distinguishable from real plants by casual observation to highly detailed botanical or artistic specimens.
Materials used in their manufacture have included painted linen and shavings of stained horn in ancient Egypt, gold and silver in ancient Rome, rice-paper in China, silkworm cocoons in Italy, colored feathers in South America, and wax and tinted shells. Modern techniques involve carved or formed soap, nylon netting stretched over wire frames, ground clay, and mass-produced injection plastic mouldings. Polyester has been the main material for manufacturing artificial flowers since the 1970s. Most artificial flowers in the market nowadays are made of polyester fabric.
Production
The industry is now highly specialized with several different manufacturing processes. Hundreds of artificial flower factories in the Pearl River delta area of Guangdong province in China have been built since the early 1980s. Thousands of 40-foot containers of polyester flowers and plants are exported to many countries every year.
Polyester and paper
Five main processes may be distinguished:
The first step consists of putting the polyester fabric in gelatine in order to stiffen it.
The second consists of cutting up the various polyester fabrics and materials employed into shapes suitable for forming the leaves, petals, etc.; this may be done with scissors, but is more often done with stamps that can cut through a dozen or more thicknesses at one blow.
Next, the veins of the leaves are impressed by means of silk screen printing with a dye, and the petals are given their natural rounded forms by goffering irons of various shapes.
The next step is to assemble |
https://en.wikipedia.org/wiki/Virtual%20Console | The Virtual Console is a line of downloadable video games for Nintendo's Wii and Wii U home video game consoles and the Nintendo 3DS family of systems.
The Virtual Console lineup consisted of titles originally released on past home and handheld consoles. These titles were run in their original forms through software emulation (excluding GBA titles on the 3DS and Wii on Wii U), therefore remaining mostly unaltered, and could be purchased from the Wii Shop Channel or Nintendo eShop for between 500 and 1200 Wii Points. They could also be purchased using real currency for $2.99 and $9.99 (3DS) and $4.99 and $9.99 (Wii U), depending on the system, rarity, and/or demand. Virtual Console's library of past games consisted of titles originating from the Nintendo Entertainment System, Super Nintendo Entertainment System, Game Boy, Game Boy Color, Nintendo 64, Game Boy Advance, and Nintendo DS, as well as Sega's Master System, Genesis/Mega Drive and Game Gear, NEC's TurboGrafx-16, and SNK's Neo Geo AES. The service for the Wii also included games for platforms that were known only in select regions, such as the Commodore 64 (Europe and North America) and Microsoft's and ASCII's MSX (Japan), as well as Virtual Console Arcade, which allowed players to download video arcade games. Virtual Console titles have been downloaded over ten million times. The distribution of past games through the Virtual Console is one of Nintendo's reasons for opposing software piracy of old console games.
On January 30, 2019, the Virtual Console service was discontinued on the Wii, following the shutdown of the Wii Shop Channel.
On March 27, 2023, the Virtual Console service was discontinued on the Wii U and Nintendo 3DS. Purchased titles remain playable.
List of Virtual Console games
Japan
There were 38 Famicom, Super Famicom, Nintendo 64, Sega Mega Drive, and PC Engine games available at launch on the Wii Virtual Console for the Japanese region. The Nintendo 3DS Virtual Console launched with 7 |
https://en.wikipedia.org/wiki/Spin%20valve | A spin valve is a device, consisting of two or more conducting magnetic materials, whose electrical resistance can change between two values depending on the relative alignment of the magnetization in the layers. The resistance change is a result of the giant magnetoresistive effect. The magnetic layers of the device align "up" or "down" depending on an external magnetic field. In the simplest case, a spin valve consists of a non-magnetic material sandwiched between two ferromagnets, one of which is fixed (pinned) by an antiferromagnet which acts to raise its magnetic coercivity and behaves as a "hard" layer, while the other is free (unpinned) and behaves as a "soft" layer. Due to the difference in coercivity, the soft layer changes polarity at lower applied magnetic field strength than the hard one. Upon application of a magnetic field of appropriate strength, the soft layer switches polarity, producing two distinct states: a parallel, low-resistance state, and an antiparallel, high-resistance state.
How it works
Spin valves work because of a quantum property of electrons (and other particles) called spin. Due to a split in the density of states of electrons at the Fermi energy in ferromagnets, there is a net spin polarisation. An electric current passing through a ferromagnet therefore carries both charge and a spin component. In comparison, a normal metal has an equal number of electrons with up and down spins so, in equilibrium situations, such materials can sustain a charge current with a zero net spin component. However, by passing a current from a ferromagnet into a normal metal it is possible for spin to be transferred. A normal metal can thus transfer spin between separate ferromagnets, subject to a long enough spin diffusion length.
Spin transmission depends on the alignment of magnetic moments in the ferromagnets. If a current is passing into a ferromagnet whose majority spin is spin up, for example, then electrons with spin up will pass through rel |
https://en.wikipedia.org/wiki/Network%20browser | A network browser is a tool used to browse a computer network. An example of this is My Network Places (or Network Neighborhood in earlier versions of Microsoft Windows). An actual program called Network Browser is offered in Mac OS 9.
See also
Browser service
Computer networking |
https://en.wikipedia.org/wiki/My%20Network%20Places | My Network Places (formerly Network Neighborhood) is the network browser feature in Windows Explorer. It was first introduced in Windows 95 and Windows NT 4.0 and was renamed My Network Places in Windows 2000 and later, before being replaced in Windows Vista.
My Network Places maintains an automatically updated history of computers which the user has accessed before, by default placed in a folder called , found in the user's user profile. This default location can be changed by modifying the pair of registry entries found under the registry keys and . The feature also allows enumerating all computers on the local network that support the Server Message Block (SMB) protocol and are open to discovery.
In a workgroup of fewer than 32 computers, the list of network destinations in My Network Places is generated by one of the computers on the network, which has been designated "Browse Master" (sometimes called "master browser"). The Browse Master is elected by system strength. Sometimes when similar systems are connected to a network, there might be a conflict between Browse Masters with unexpected consequences, such as the disappearance of the list altogether or some system becoming unreachable. A system can be forced to decline Browse Master status by disabling the Browser service and rebooting. In a workgroup of 32 computers or more, the shortcuts are created automatically when the user opens a shared network resource, such as a printer or shared folder.
Starting with Windows Vista, My Network Places is removed in favor of an integrated "Network" node in Windows Explorer. This node can only enumerate network computers but can do so via WS-Discovery and UPnP protocols, in addition to SMB.
See also
Special folder |
https://en.wikipedia.org/wiki/Molecular%20gastronomy | Molecular gastronomy is the scientific approach of cuisine from primarily the perspective of chemistry. The composition (molecular structure), properties (mass, viscosity, etc) and transformations (chemical reactions, reactant products) of an ingredient are addressed and utilized in the preparation and appreciation of the ingested products. It is a branch of food science that approaches the preparation and enjoyment of nutrition from the perspective of a scientist at the scale of atoms, molecules, and mixtures.
Nicholas Kurti, Hungarian physicist, and Hervé This, at the INRA in France, coined "Molecular and Physical Gastronomy" in 1988.
Examples
Eponymous recipes
New dishes named after famous scientists include:
Gibbs – infusing vanilla pods in egg white with sugar, adding olive oil and then microwave cooking. Named after physicist Josiah Willard Gibbs (1839–1903).
Vauquelin – using orange juice or cranberry juice with added sugar when whipping eggs to increase the viscosity and to stabilize the foam, and then microwave cooking. Named after Nicolas Vauquelin (1763–1829), one of Lavoisier's teachers.
Baumé – soaking a whole egg for a month in alcohol to create a coagulated egg. Named after the French chemist Antoine Baumé (1728–1804).
History
There are many branches of food science that study different aspects of food, such as safety, microbiology, preservation, chemistry, engineering, and physics. Until the advent of molecular gastronomy, there was no branch dedicated to studying the chemical processes of cooking in the home and in restaurants. Food science has primarily been concerned with industrial food production and, while the disciplines may overlap, they are considered separate areas of investigation.
The creation of the discipline of molecular gastronomy was intended to bring together what had previously been fragmented and isolated investigations into the chemical and physical processes of cooking into an organized discipline within food science, to |
https://en.wikipedia.org/wiki/Lanthanum%20gallium%20silicate | Lanthanum gallium silicate (referred to as LGS in this article), also known as langasite, has a chemical formula of the form A3BC3D2O14, where A, B, C and D indicate particular cation sites. A is a decahedral (Thomson cube) site coordinated by 8 oxygen atoms. B is octahedral site coordinated by 6 oxygen atoms, and C and D are tetrahedral sites coordinated by 4 oxygen atoms. In this material, lanthanum occupied the A-sites, gallium the B, C and half of D-sites, and, silicon the other half of D-sites.
LGS is a piezoelectric material, with no phase transitions up to its melting point of 1470 °C. Single crystal LGS can be grown via the Czochralski method, in which crystallization is initiated on a rotating seed crystal lowered into the melt followed by pulling from the melt. The growth atmosphere is usually argon or nitrogen with up to 5% of oxygen. The use of oxygen in the growth environment is reported to suppress gallium loss from the melt; however, too high an oxygen level can lead to platinum (crucible material used for the melt) dissolution in the melt. The growth of LGS is primarily along the z direction. Currently the 3-inch (76 mm) langasite boules produced commercially have growth rates of 1.5 to 5 mm/h. The quality of the crystals tends to improve as the growth rate is reduced.
See also
Ceramic
lanthanum gallium tantalum oxide, langatite (CAS RN 83381-05-9) La6Ga11TaO28 (i.e., La3Ga5.5Ta00.5O14) |
https://en.wikipedia.org/wiki/Floppy-disk%20controller | A floppy-disk controller (FDC) has evolved from a discrete set of components on one or more circuit boards to a special-purpose integrated circuit (IC or "chip") or a component thereof. An FDC directs and controls reading from and writing to a computer's floppy disk drive (FDD). The FDC is responsible for reading data presented from the host computer and converting it to the drive's on-disk format using one of a number of encoding schemes, like FM encoding (single density) or MFM encoding (double density), and reading those formats and returning it to its original binary values.
Depending on the platform, data transfers between the controller and host computer would be controlled by the computer's own microprocessor, or an inexpensive dedicated microprocessor like the MOS 6507 or Zilog Z80. Early controllers required additional circuitry to perform specific tasks like providing clock signals and setting various options. Later designs included more of this functionality on the controller and reduced the complexity of the external circuitry; single-chip solutions were common by the later 1980s.
By the 1990s, the floppy disk was increasingly giving way to hard drives, which required similar controllers. In these systems, the controller also often combined a microcontroller to handle data transfer over standardized connectors like SCSI and IDE that could be used with any computer. In more modern systems, the FDC, if present at all, is typically part of the many functions provided by a single super I/O chip.
History
The first floppy disk drive controller (FDC) like the first floppy disk drive (the IBM 23FD) shipped in 1971 as a component in the IBM 2385 Storage Control Unit for the IBM 2305 fixed head disk drive, and of the System 370 Models 155 and 165. The IBM 3830 Storage Control Unit, a contemporaneous and quite similar controller, uses its internal processor to control a 23FD. The resultant FDC is a simple implementation in IBMs’ MST hybrid circuits on a few pr |
https://en.wikipedia.org/wiki/DO-178B | DO-178B, Software Considerations in Airborne Systems and Equipment Certification is a guideline dealing with the safety of safety-critical software used in certain airborne systems. It was jointly developed by the safety-critical working group RTCA SC-167 of the Radio Technical Commission for Aeronautics (RTCA) and WG-12 of the European Organisation for Civil Aviation Equipment (EUROCAE). RTCA published the document as RTCA/DO-178B, while EUROCAE published the document as ED-12B. Although technically a guideline, it was a de facto standard for developing avionics software systems until it was replaced in 2012 by DO-178C.
The Federal Aviation Administration (FAA) applies DO-178B as the document it uses for guidance to determine if the software will perform reliably in an airborne environment, when specified by the Technical Standard Order (TSO) for which certification is sought. In the United States, the introduction of TSOs into the airworthiness certification process, and by extension DO-178B, is explicitly established in Title 14: Aeronautics and Space of the Code of Federal Regulations (CFR), also known as the Federal Aviation Regulations, Part 21, Subpart O.
Software level
The Software Level, also termed the Design Assurance Level (DAL) or Item Development Assurance Level (IDAL) as defined in ARP4754 (DO-178C only mentions IDAL as synonymous with Software Level), is determined from the safety assessment process and hazard analysis by examining the effects of a failure condition in the system. The failure conditions are categorized by their effects on the aircraft, crew, and passengers.
Catastrophic – Failure may cause a crash. Error or loss of critical function required to safely fly and land aircraft.
Hazardous – Failure has a large negative impact on safety or performance, or reduces the ability of the crew to operate the aircraft due to physical distress or a higher workload, or causes serious or fatal injuries among the passengers. (Safety-significant |
https://en.wikipedia.org/wiki/Erd%C5%91s%E2%80%93Bacon%20number | A person's Erdős–Bacon number is the sum of one's Erdős number—which measures the "collaborative distance" in authoring academic papers between that person and Hungarian mathematician Paul Erdős—and one's Bacon number—which represents the number of links, through roles in films, by which the person is separated from American actor Kevin Bacon. The lower the number, the closer a person is to Erdős and Bacon, which reflects a small world phenomenon in academia and entertainment.
To have a defined Erdős–Bacon number, it is necessary to have both appeared in a film and co-authored an academic paper, although this in and of itself is not sufficient as one's co-authors must have a known chain leading to Paul Erdős, and one's film must have actors eventually leading to Kevin Bacon.
Academic scientists
Mathematician Daniel Kleitman has an Erdős–Bacon number of 3. He co-authored papers with Erdős and has a Bacon number of 2 via Minnie Driver in Good Will Hunting; Driver and Bacon appeared together in Sleepers.
Like Kleitman, mathematician Bruce Reznick has co-authored a paper with Erdős and has a Bacon number of 2, via Roddy McDowall in the film Pretty Maids All in a Row, giving him an Erdős–Bacon number of 3 as well.
Physicist Nicholas Metropolis has an Erdős number of 2, and also a Bacon number of 2, giving him an Erdős–Bacon number of 4.
Metropolis and Richard Feynman both worked on the Manhattan Project at Los Alamos Laboratory. Via Metropolis, Feynman has an Erdős number of 3 and, from having appeared in the film Anti-Clock alongside Tony Tang, Feynman also has a Bacon number of 3. Richard Feynman thus has an Erdős–Bacon number of 6.
Theoretical physicist Stephen Hawking has an Erdős–Bacon number of 6: his Bacon number of 2 (via his appearance alongside John Cleese in Monty Python Live (Mostly), who acted alongside Kevin Bacon in The Big Picture) is lower than his Erdős number of 4.
Similarly to Stephen Hawking, scientist Carl Sagan has an Erdős–Bacon number of 6 |
https://en.wikipedia.org/wiki/Calie%20Pistorius | Carl Wilhelm Irene ("Calie") Pistorius (born 9 August 1958) is a South African academic who is a former Vice-Chancellor of the University of Hull, Kingston upon Hull, United Kingdom. He announced, on 1 August 2016, that he would be stepping down from this role at the end of January 2017. His successor at Hull was Professor Susan Lea.
Education
Pistorius obtained the degree B.Sc (Eng) (cum laude) in electronic engineering from the University of Pretoria in 1979 and the degree B.Eng (Hons) (cum laude) in electronic engineering from the same university in 1981. He obtained a M.S. degree in electrical engineering from the Ohio State University in the U.S. in 1984, a Ph.D. degree in electrical engineering also from the Ohio State University in 1986, and a Master's degree in management (M.B.A.) from the MIT Sloan School of Management in 1994.
Academic career
Pistorius is a consultant to industry and government on issues relating to strategy, management of technology, technological innovation, competitiveness and national technological policy. He is also a member of the National Advisory Council on Innovation in South Africa.
Pistorius has published widely both nationally and internationally and has 107 academic publications to his credit. He has received numerous awards and prizes including the prize for the best Ph.D. dissertation from the ElectroScience Laboratory at the Ohio State University, the President's Award from the National Research Foundation and the Bill Venter Prize for outstanding contributions to research published in book form by university personnel in South Africa.
At the university, Pistorius was head of the Department of Electronic and Electrical Engineering for five years, Director of the Institute for Technological Innovation for four years, Director of Information Technology for two years and Dean of the Faculty for one and a half years.
On 25 February 2009, it was announced that Pistorius would be stepping down from his position as Vice-Chan |
https://en.wikipedia.org/wiki/STAT%20protein | Members of the signal transducer and activator of transcription (STAT) protein family are intracellular transcription factors that mediate many aspects of cellular immunity, proliferation, apoptosis and differentiation. They are primarily activated by membrane receptor-associated Janus kinases (JAK). Dysregulation of this pathway is frequently observed in primary tumors and leads to increased angiogenesis which enhances the survival of tumors and immunosuppression. Gene knockout studies have provided evidence that STAT proteins are involved in the development and function of the immune system and play a role in maintaining immune tolerance and tumor surveillance.
STAT family
The first two STAT proteins were identified in the interferon system. There are seven mammalian STAT family members that have been identified: STAT1, STAT2, STAT3, STAT4, STAT5 (STAT5A and STAT5B), and STAT6.
STAT1 homodimers are involved in type II interferon signalling, and bind to the GAS (Interferon-Gamma Activated Sequence) promoter to induce expression of interferon stimulated genes (ISG). In type I interferon signaling, STAT1-STAT2 heterodimer combines with IRF9 (Interferon Response Factor) to form ISGF3 (Interferon Stimulated Gene Factor), which binds to the ISRE (Interferon-Stimulated Response Element) promoter to induce ISG expression.
Structure
All seven STAT proteins share a common structural motif consisting of an N-terminal domain followed by a coiled-coil, DNA-binding domain, linker, Src homology 2 (SH2), and a C-terminal transactivation domain. Much research has focused on elucidating the roles each of these domains play in regulating different STAT isoforms. Both the N-terminal and SH2 domains mediate homo or heterodimer formation, while the coiled-coil domain functions partially as a nuclear localization signal (NLS). Transcriptional activity and DNA association are determined by the transactivation and DNA-binding domains, respectively.
Activation
Extracellular binding o |
https://en.wikipedia.org/wiki/Social%20studies%20of%20finance | Social studies of finance is an interdisciplinary research area that combines perspectives from anthropology, economic sociology, science and technology studies, international political economy, behavioral finance, and cultural studies in the study of financial markets and financial instruments. Work in social studies of finance emphasizes the social and cultural dimensions of financial activities, but focuses also on technical and economic dimensions such as pricing and trading.
History
Financial markets have been an object for sociological inquiry since, at least, Max Weber’s Die Börse. The rise of quantitative financial theory in financial economics from the 1950s onwards has led to an academic specialization on financial markets rather focused on economic modeling, and poorly attentive to sociological aspects. In the 1980s, a number of economic sociologists developed empirical investigation on the social structure and cultural characteristics of financial markets, especially in the US. Such pioneering researcher included contributions from Wayne E. Baker, Mitchel Y. Abolafia and Charles W. Smith, and was based on methods such as ethnographic observation or social network analysis. In the 1990s, a number of researchers from the field of science and technology studies such as Karin Knorr-Cetina and Donald A. MacKenzie started also developing empirical research in this area, with close attention to the role of expert knowledge and technology in financial activities.
Main topics
Research topics in social studies of finance include the cultural world and work habits of professionals in financial markets, the globalization and regulation of financial services, the processes of innovation in the financial industry and the problems of risk and uncertainty that characterize such processes.
Major references
Adler, Patricia A. and Adler, Peter (eds) (1984) The Social Dynamics of Financial Markets, Greenwich (Connecticut): The JAI Press.
Bernstein, Peter (1993) Capita |
https://en.wikipedia.org/wiki/Cyberfeminism | Cyberfeminism is a feminist approach which foregrounds the relationship between cyberspace, the Internet, and technology. It can be used to refer to a philosophy, methodology or community. The term was coined in the early 1990s to describe the work of feminists interested in theorizing, critiquing, exploring and re-making the Internet, cyberspace and new-media technologies in general. The foundational catalyst for the formation of cyberfeminist thought is attributed to Donna Haraway's "A Cyborg Manifesto", third wave feminism, post-structuralist feminism, riot grrrl culture and the feminist critique of the alleged erasure of women within discussions of technology.
Definition
Cyberfeminism is a sort of alliance that wants to defy any sort of boundaries of identity and definition and rather be truly postmodern in its potential for radical openness. This is seen with the 1997 Old Boys Network's 100 anti-theses which lists the 100 ways "cyberfeminism is not." Cornelia Sollfrank from the Old Boys Network states that:Cyberfeminism is a myth. A myth is a story of unidentifiable origin, or of different origins. A myth is based on one central story which is retold over and over in different variations. A myth denies one history as well as one truth, and implies a search for truth in the spaces, in the differences between the different stories. Speaking about Cyberfeminism as a myth, is not intended to mystify it, it simply indicates that Cyberfeminism only exists in plural.Mia Consalvo defines cyberfeminism as:
a label for women—especially young women who might not even want to align with feminism's history—not just to consume new technologies but to actively participate in their making;
a critical engagement with new technologies and their entanglement with power structures and systemic oppression.
The dominant cyberfeminist perspective takes a utopian view of cyberspace and the Internet as a means of freedom from social constructs such as gender, sex difference and ra |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.