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Inflationary bias Thus, a solution to this bias would be to delegate monetary policy to an independent central bank. Theoretically, an independent central bank would have little incentive to cheat, more credibility in its commitment and then would lead to a lower inflation level and act like a guardian of price stability. For example, the European central bank and the Fed are independent central banks. This negative correlation between independence of central bank and inflation has first been proved by the economists Alena and Summers in 1993. Aside from the independence of the central bank, credibility of monetary policies can be achieved through contracts, conservatism and reputation system. Moreover, as an opposition to discretionary policy leading to inflationary bias, rule-based monetary policies are another (less flexible) suggestion to prevent this bias. This is notably advocated by Milton Friedman. His suggestion is to fixe a monetary supply growth target suitable with the natural level of output, in order to guarantee growth stability in the long run: if growth exceeds its structural potential rate, the money supply becomes insufficient and interest rates rise, which curbs growth and prevents inflationary overheating. Conversely, a fall in rates would support activity if growth were below its long-term potential. But a critical to this solution is that it would at the same time take away the possibility of responding to demand shocks | https://en.wikipedia.org/wiki?curid=29583998 | 502,606 |
Nanomechanics As a fundamental science, nanomechanics is based on some empirical principles (basic observations), namely general mechanics principles and specific principles arising from the smallness of physical sizes of the object of study. General mechanics principles include: Due to smallness of the studied object, nanomechanics also accounts for: These principles serve to provide a basic insight into novel mechanical properties of nanometer objects. Novelty is understood in the sense that these properties are not present in similar macroscale objects or much different from the properties of those (e.g., nanorods vs. usual macroscopic beam structures). In particular, smallness of the subject itself gives rise to various surface effects determined by higher surface-to-volume ratio of nanostructures, and thus affects mechanoenergetic and thermal properties (melting point, heat capacitance, etc.) of nanostructures. Discreteness serves a fundamental reason, for instance, for the dispersion of mechanical waves in solids, and some special behavior of basic elastomechanics solutions at small scales. Plurality of degrees of freedom and the rise of thermal fluctuations are the reasons for thermal tunneling of nanoparticles through potential barriers, as well as for the cross-diffusion of liquids and solids. Smallness and thermal fluctuations provide the basic reasons of the Brownian motion of nanoparticles | https://en.wikipedia.org/wiki?curid=14661057 | 290,377 |
Microfluidics Additionally, microfluidic manufacturing advances mean that makers can produce the devices in low-cost plastics and automatically verify part quality. Advances in microfluidics technology are revolutionizing molecular biology procedures for enzymatic analysis (e.g., glucose and lactate assays), DNA analysis (e.g., polymerase chain reaction and high-throughput sequencing), proteomics, and in chemical synthesis. The basic idea of microfluidic biochips is to integrate assay operations such as detection, as well as sample pre-treatment and sample preparation on one chip. An emerging application area for biochips is clinical pathology, especially the immediate point-of-care diagnosis of diseases. In addition, microfluidics-based devices, capable of continuous sampling and real-time testing of air/water samples for biochemical toxins and other dangerous pathogens, can serve as an always-on "bio-smoke alarm" for early warning. Microfluidic technology has led to the creation of powerful tools for biologists to control the complete cellular environment, leading to new questions and discoveries. Many diverse advantages of this technology for microbiology are listed below: Some of these areas are further elaborated in the sections below. In open microfluidics, at least one boundary of the system is removed, exposing the fluid to air or another interface (i.e. liquid) | https://en.wikipedia.org/wiki?curid=18906 | 363,946 |
Delivery versus payment or DvP is a common form of settlement for securities. The process involves the simultaneous delivery of all documents necessary to give effect to a transfer of securities in exchange for the receipt of the stipulated payment amount. Alternatively, it may involve transfers of two securities in such a way as to ensure that delivery of one security occurs if and only if the corresponding delivery of the other security occurs. This is done to avoid settlement risk such as where one party fails to deliver the security when the other party has already delivered the cash when settling a securities trade. The market crash of October 1987 drew global attention to potential weaknesses in the standards applied for clearance and settlement. Numerous studies resulted, among which was one from the Group of Thirty which pioneered standards for providers of securities settlement services. The report included nine recommendations, one of which was that "(DvP) should be the method for settling all securities transactions with systems in place by 1992." In December 1990, the Committee on Payment and Settlement Systems (CPSS), consisting of representatives from the major central banks, initiated further study of DVP. Its report in September 1992 found three ways of achieving DvP: From an operational perspective DVP is a sale transaction of negotiable securities (in exchange for cash payment) that can be instructed to a settlement agent using MT 543 (in the ISO15022 standard) | https://en.wikipedia.org/wiki?curid=851862 | 237,792 |
PAL In the early 1970s some Japanese set manufacturers developed decoding systems to avoid paying royalties to Telefunken. The Telefunken licence covered any decoding method that relied on the alternating subcarrier phase to reduce phase errors. This included very basic decoders that relied on the human eye to average out the odd/even line phase errors. One solution was to use a 1H analogue delay line to allow decoding of only the odd or even lines. For example, the chrominance on odd lines would be switched directly through to the decoder and also be stored in the delay line. Then, on even lines, the stored odd line would be decoded again. This method effectively converted to NTSC. Such systems suffered hue errors and other problems inherent in NTSC and required the addition of a manual hue control. and NTSC have slightly divergent colour spaces, but the colour decoder differences here are ignored. The SECAM patents predate those of by several years (1956 vs. 1962). Its creator, Henri de France, in search of a response to known NTSC hue problems, came up with ideas that were to become fundamental to both European systems, namely: 1) colour information on two successive TV lines is very similar and vertical resolution can be halved without serious impact on perceived visual quality 2) more robust colour transmission can be achieved by spreading information on two TV lines instead of just one 3) information from the two TV lines can be recombined using a delay line | https://en.wikipedia.org/wiki?curid=24438 | 419,586 |
American Institute of Chemical Engineers The (AIChE) is a professional organization for chemical engineers. AIChE was established in 1908 to distinguish chemical engineers as a profession independent of chemists and mechanical engineers. As of 2018, AIChE had over 60,000 members, including members from over 110 countries worldwide. Student chapters at various universities around the world have also been established throughout its history. The student chapters tend to focus on providing networking opportunities in both academia and in industry as well as increasing student involvement locally and nationally. In 1905, "The Chemical Engineer" rounded out its first year of publication with an editorial by its founder and prominent engineer, Richard K. Meade, that propounded the question: "Why not the American Society of Chemical Engineers?" He went on to say: "The profession is now a recognized one and there are probably at least five hundred chemical engineers in this country". The mechanical, civil, electrical, and mining engineers in the United States each had already established a national society, so Meade's editorial was quite pertinent. But it took time for the idea to take root and Meade kept promoting it for the next two years. Finally, in 1907, he issued a call for a preliminary meeting to be held in Atlantic City in June, 1907. Some early leaders of the profession, Charles F. McKenna, William H. Walker, William Miller Booth, Samuel P | https://en.wikipedia.org/wiki?curid=3042131 | 66,405 |
Melonite is a telluride of nickel; it is a metallic mineral. Its chemical formula is NiTe. It is opaque and white to reddish-white in color, oxidizing in air to a brown tarnish. It was first described from the Melones and Stanislaus mine in Calaveras County, California in 1866, by Frederick Augustus Genth. occurs as trigonal crystals, which cleave in a (0001) direction. It has a specific gravity of 7.72 and a hardness of 1–1.5 (very soft). | https://en.wikipedia.org/wiki?curid=2231135 | 3,278 |
Working fluid selection Isentropic fluids have two extrema (d"s"/d"T"=0) on the saturation vapour curve. Practically, there are some fluids which are very close to this behaviour or at least in a certain temperature range, for example trichlorofluoromethane (CClF). Another problem is the extent of how dry or isentropic the fluid behaves, which has significant practical importance when designing for example an Organic Rankine Cycle layout and choosing proper expander. A new kind of classification was proposed by G. Györke et al. to resolve the problems and deficiencies of the traditional three-class classification system. The new classification is also based on the shape of the saturation vapour curve of the fluid in temperature-entropy diagram similarly to the traditional one. The classification uses a "chacteristic-point based method" to differentiate the fluids. The method defines three primary and two secondary characteristic points. The relative location of these points on the temperature-entropy saturation curve defines the categories. Every pure fluid has primary characteristic points A, C and Z: The two secondary characteristic points, namely M and N are defined as local entropy extrema on the saturation vapour curve, more accurately, at those points, where with the decrease of the saturation temperature entropy stays constant: d"s"/d"T"=0 | https://en.wikipedia.org/wiki?curid=57210042 | 88,202 |
Predistortion is a technique used to improve the linearity of radio transmitter amplifiers. Radio transmitter amplifiers in most telecommunications systems are required to be "linear", in that they must accurately reproduce the signal present at their input. An amplifier that compresses its input or has a non-linear input/output relationship causes the output signal to splatter onto adjacent radio frequencies. This causes interference on other radio channels. There are many different ways of specifying the linearity of a power amplifier, including P1dB, Inter-modulation Distortion (IMD), AM-to-PM, spectral regrowth and Noise Power Ratio (NPR). For a truly linear system, these measures are in a sense all equivalent. That is, a power amplifier with low inter-modulation distortion will also have low spectral regrowth and low AM-to-PM distortion. Likewise there are two equivalent ways of conceptualizing how predistortion amplifiers work: correcting gain and phase distortions, or cancelling inter-modulation products. Usually one of the two conceptualizations is preferred when designing predistortion circuitry; however the end result is generally the same. A predistorter designed to correct gain and phase non-linearities will also improve IMD, while one which targets inter-modulation products will also reduce gain and phase perturbations. When combined with the target amplifier, the linearizer produces an overall system that is more linear and reduces the amplifier's distortion | https://en.wikipedia.org/wiki?curid=1635476 | 249,794 |
Film noir Expressionism-orientated filmmakers had free stylistic rein in Universal horror pictures such as "Dracula" (1931), "The Mummy" (1932)—the former photographed and the latter directed by the Berlin-trained Karl Freund—and "The Black Cat" (1934), directed by Austrian émigré Edgar G. Ulmer. The Universal horror film that comes closest to noir, in story and sensibility, is "The Invisible Man" (1933), directed by Englishman James Whale and photographed by American Arthur Edeson. Edeson later photographed "The Maltese Falcon" (1941), widely regarded as the first major film noir of the classic era. Josef von Sternberg was directing in Hollywood during the same period. Films of his such as "Shanghai Express" (1932) and "The Devil Is a Woman" (1935), with their hothouse eroticism and baroque visual style, anticipated central elements of classic noir. The commercial and critical success of Sternberg's silent "Underworld" (1927) was largely responsible for spurring a trend of Hollywood gangster films. Successful films in that genre such as "Little Caesar" (1931), "The Public Enemy" (1931) and "Scarface" (1932) demonstrated that there was an audience for crime dramas with morally reprehensible protagonists. An important, possibly influential, cinematic antecedent to classic noir was 1930s French poetic realism, with its romantic, fatalistic attitude and celebration of doomed heroes. The movement's sensibility is mirrored in the Warner Bros. drama "I Am a Fugitive from a Chain Gang" (1932), a forerunner of noir | https://en.wikipedia.org/wiki?curid=10802 | 259,158 |
Kotmale Biyagama transmission line is one of Sri Lanka's critical transmission lines that connects the load center Colombo to hydroelectricity generation of Mahaweli Complex. | https://en.wikipedia.org/wiki?curid=35574265 | 505,644 |
Stoichiometry is the calculation of reactants and products in chemical reactions. is founded on the law of conservation of mass where the total mass of the reactants equals the total mass of the products, leading to the insight that the relations among quantities of reactants and products typically form a ratio of positive integers. This means that if the amounts of the separate reactants are known, then the amount of the product can be calculated. Conversely, if one reactant has a known quantity and the quantity of the products can be empirically determined, then the amount of the other reactants can also be calculated. This is illustrated in the image here, where the balanced equation is: Here, one molecule of methane reacts with two molecules of oxygen gas to yield one molecule of carbon dioxide and two molecules of water. This particular chemical equation is an example of complete combustion. measures these quantitative relationships, and is used to determine the amount of products and reactants that are produced or needed in a given reaction. Describing the quantitative relationships among substances as they participate in chemical reactions is known as "reaction stoichiometry". In the example above, reaction stoichiometry measures the relationship between the quantities of methane and oxygen that react to form carbon dioxide and water | https://en.wikipedia.org/wiki?curid=28650 | 83,206 |
Saint Thomas Tower (), also known as Fort Saint Thomas (), is a large bastioned watchtower in Marsaskala, Malta. It was built in 1614, the third of six Wignacourt towers. An artillery battery was added to the tower in the early 18th century. is the largest watchtower in Malta. was built above the shore on the seaward face of the headland of "il-Ħamrija" in Marsaskala. It is a substantial fortification intended to prevent the landing of troops in the sheltered anchorages of Marsaskala Creek and St Thomas' Bay. Construction of the tower was approved in July 1614, at the time of the raid of Żejtun, in which an Ottoman fleet managed to land at St Thomas' Bay. The tower was named after a chapel dedicated to St Thomas which stood close to where the tower now lies. It cost 13,450 scudi, 6 tari and 4 grani to build, making it the second most expensive Wignacourt tower, after Saint Mary's Tower. The tower's architect is unknown. There are claims that it was designed by Vittorio Cassar, but these are disputed since Cassar was probably dead when work on the tower began. The tower has very thick walls and has four pentagonal bastioned turrets projecting outwards on each corner. The tower's entrance was through a vaulted doorway with a wooden drawbridge. The drawbridge is still partially intact and it is the only original one to have survived in Malta. The tower is surrounded by a rock-hewn ditch | https://en.wikipedia.org/wiki?curid=2400637 | 345,583 |
Revolving door (politics) These organisations, numbering 4,576, received 98 percent of the expenses for state projects without being subject to the bidding processes faced by private companies. Over 50 years ending in 2010, 68 high-level government bureaucrats have taken jobs with electricity suppliers after retirement from their government positions. In 2011, 13 retired government bureaucrats were employed in senior positions in Japanese electric utilities. Amakudari is subject to rules which were revised in April 2007 in response to corruption scandals. Under the new rules, ministries are instructed to slowly stop helping bureaucrats land new jobs over three years starting in 2009. Instead, a job center to be set up by the end of 2008 would take on the role, and government agencies and ministries will be prohibited from brokering new jobs for retirees. However, the law removed a two-year ban that prevented retiring officials from taking jobs with companies with which they had official dealings during the five years before retirement, which may increase amakudari. It also left considerable loopholes, including not placing restrictions on "watari" in which retired bureaucrats move from one organization to another. Bureaucrats could retire to a job at another government agency, and then switch jobs to a private company later. Critics say that the government could better prevent Amakudari by raising the retirement age for bureaucrats above 50 | https://en.wikipedia.org/wiki?curid=15029435 | 492,417 |
Electronic waste This is land-filled or recycled, along with alternative metal or plastic scraps. There is the colossal compromise that the toxins are not drawn want of accordingly, or they are chosen want of by an informal sector and converted without well safeguarding the laborers while venting the contaminations in e-waste. Although the e-waste claim is on the rise, a flourishing quantity of countries are embracing e-waste regulation. National e-waste governance orders enclose 66% of the world population, a rise from 44% that was reached in 2014 Looking at European continent, European Union has addressed the issue of electronic Waste by introducing two pieces of legislation. The first legislation, named "The Directive on waste electrical and electronic equipment" or "WEEE directive" entered into force in 2003. The main aim of this directive was to regulate and motivate electronic waste recycling and re-use in member states at that moment. This regulative was revised in 2008, and the new WEEE directive came into force in 2014. Furthermore, European Union has also implemented the Directive on the restriction of the use of certain hazardous substances in electrical and electronica equipment in 2003. This documents was additionally revised in 2012. When it comes to Western Balkan countries, North Macedonia has adopted a Law on Batteries and Accumulators in 2010, followed by the Law on Management of electrical and electronic equipment in 2012 | https://en.wikipedia.org/wiki?curid=3887690 | 455,934 |
Asset protection (sometimes also referred to as "debtor-creditor law") is a set of legal techniques and a body of statutory and common law dealing with protecting assets of individuals and business entities from civil money judgments. The goal of asset protection planning is to insulate assets from claims of creditors without perjury or tax evasion. consists of methods available to protect assets from liabilities arising elsewhere. It should not be confused with "limiting liability", which concerns the ability to stop or constrain liability to the asset or activity from which it arises. Assets that are shielded from creditors by law are few: common examples include some home equity, certain retirement plans and interests in LLCs and limited partnerships (and even these are not always unreachable). Assets that are almost always unreachable are those to which one does not hold legal title. In many cases it is possible to vest legal title to personal assets in a trust, an agent or a nominee, while retaining all the control of the assets. The goal of asset protection is similar to bankruptcy, and the two practice areas go hand-in-hand. When a debtor has none to few assets, the bankruptcy route is preferable. When the debtor has significant assets, asset protection may be the solution | https://en.wikipedia.org/wiki?curid=17065775 | 497,860 |
Television However, it was not possible to practically implement such a digital TV service until the adoption of DCT video compression technology made it possible in the early 1990s. In the mid-1980s, as Japanese consumer electronics firms forged ahead with the development of HDTV technology, the MUSE analog format proposed by NHK, a Japanese company, was seen as a pacesetter that threatened to eclipse U.S. electronics companies' technologies. Until June 1990, the Japanese MUSE standard, based on an analog system, was the front-runner among the more than 23 different technical concepts under consideration. Then, an American company, General Instrument, demonstrated the feasibility of a digital television signal. This breakthrough was of such significance that the FCC was persuaded to delay its decision on an ATV standard until a digitally based standard could be developed. In March 1990, when it became clear that a digital standard was feasible, the FCC made a number of critical decisions. First, the Commission declared that the new ATV standard must be more than an enhanced analog signal, but be able to provide a genuine HDTV signal with at least twice the resolution of existing television images.(7) Then, to ensure that viewers who did not wish to buy a new digital television set could continue to receive conventional television broadcasts, it dictated that the new ATV standard must be capable of being "simulcast" on different channels | https://en.wikipedia.org/wiki?curid=29831 | 381,578 |
Welding defect However, in Cyclically Loaded Structures, arc strikes may result in stress concentrations that would be detrimental to the serviceability of such structures and should be ground smooth and visually inspected for cracks. Residual stresses can reduce the strength of the base material, and can lead to catastrophic failure through cold cracking. Cold cracking is limited to steels and is associated with the formation of martensite as the weld cools. The cracking occurs in the heat-affected zone of the base material. To reduce the amount of distortion and residual stresses, the amount of heat input should be limited, and the welding sequence used should not be from one end directly to the other, but rather in segments. Cold cracking only occurs when all the following preconditions are met: Eliminating any one of these will eliminate this condition. Crater cracks occur when a welding arc is broken, a crater will form if adequate molten metal is available to fill the arc cavity. Hat cracks get their name from the shape of the cross-section of the weld, because the weld flares out at the face of the weld. The crack starts at the fusion line and extends up through the weld. They are usually caused by too much voltage or not enough speed. Hot cracking, also known as solidification cracking, can occur with all metals, and happens in the fusion zone of a weld. To diminish the probability of this type of cracking, excess material restraint should be avoided, and a proper filler material should be utilized | https://en.wikipedia.org/wiki?curid=25324417 | 423,593 |
CeCoIn5 CeCoIn ("Cerium-Cobalt-Indium 5") is a heavy-fermion superconductor with a layered crystal structure, with somewhat two-dimensional electronic transport properties. The critical temperature of 2.3 K is the highest among all of the Ce-based heavy-fermion superconductors. CeCoIn is a member of a rich family of heavy-fermion compounds. CeIn is heavy-fermion metal with cubic crystal structure that orders antiferromagnetically below 10K. With applying external pressure, antiferromagnetism in CeIn is continuously suppressed, and a superconducting dome emerges in the phase diagram near the antiferromagnetic quantum critical point. CeCoIn has a tetragonal crystal structure, and the unit cell of CeCoIn can be considered as 'CeIn with an additional CoIn layer per unit cell'. Closely related to CeCoIn is the heavy-fermion material CeRhIn, which has the same crystal structure and which orders antiferromagnetically below 4K, but does not become superconducting at ambient pressure. At high pressure CeRhIn becomes superconducting with a maximum T slightly above 2 K at a pressure around 2 GPa, and at the same pressure the Fermi surface of CeRhIn changes suggesting so-called local quantum criticality. Also the compound PuCoGa, which is a superconductor with T approximately 18.5 K and which can be considered an intermediate between heavy-fermion and cuprate superconductors, has the same crystal structure | https://en.wikipedia.org/wiki?curid=42691680 | 21,065 |
Ignition system This allows for greater timing flexibility, and engine performance; especially when designed hand-in-hand with the engine carburetor. In an Engine Management System (EMS), electronics control fuel delivery and ignition timing. Primary sensors on the system are crankshaft angle (crankshaft or TDC position), airflow into the engine and throttle position. The circuitry determines which cylinder needs fuel and how much, opens the requisite injector to deliver it, then causes a spark at the right moment to burn it. Early EMS systems used an analogue computer to accomplish this, but as embedded systems dropped in price and became fast enough to keep up with the changing inputs at high revolutions, digital systems started to appear. Some designs using an EMS retain the original ignition coil, distributor and high-tension leads found on cars throughout history. Other systems dispense with the distributor altogether and have individual coils mounted directly atop each spark plug. This removes the need for both distributor and high-tension leads, which reduces maintenance and increases long-term reliability. Modern EMSs read in data from various sensors about the crankshaft position, intake manifold temperature, intake manifold pressure (or intake air volume), throttle position, fuel mixture via the oxygen sensor, detonation via a knock sensor, and exhaust gas temperature sensors. The EMS then uses the collected data to precisely determine how much fuel to deliver and when and how far to advance the ignition timing | https://en.wikipedia.org/wiki?curid=362070 | 376,847 |
Broadcast-safe video (broadcast legal or legal signal) is a term used in the broadcast industry to define video and audio compliant with the technical or regulatory broadcast requirements of the target area or region the feed might be broadcasting to. In the United States, the Federal Communications Commission (FCC) is the regulatory authority; in most of Europe, standards are set by the European Broadcasting Union (EBU). Broadcast safe standards for 625 lines of Standard Definition (Inaccurately referred to as PAL, a colour encoding that is usually used with such systems) video are: Broadcast safe standards for 525 lines of Standard Definition (System M, NTSC) video are: Digital broadcasting is very different from analog. The NTSC and PAL standards describe both transmission of the signal and how the electrical signal is converted into an image. In digital, there is a separation between the subject of how data is to be transmitted from tower to TV, and the subject of what content that data might contain. While data transmission is likely to be a fixed and consistent affair, the content could vary from High Definition video one hour, to SD multicasting the next, and even to non-video datacasting. In the US, 8VSB transmits the data, while MPEG-2 encodes pictures and sound. Broadcast engineers in North America usually line up their audio gear to nominal reference level of 0 dB on a VU meter aligned to +4dBu or -20dBFs, in Europe equating to roughly +4 dBm or -18 dBFS | https://en.wikipedia.org/wiki?curid=15928363 | 405,094 |
Quick Detach sling mount Quick Detach sling mounts (QD), also called Flush Cup sling mounts, is a type of mounting point used for attaching slings. "QD sling swivel" usually refer to the part attached to the sling, while "flush cup" refer to the corresponding socket on the firearm. The system consists of a push button swivel attached to the sling (approximate diameter 9.4 mm, a little under inches) which is placed into a mounting socket on the firearm (approximate diameter 9.6 mm, a little over inches). The swivel is kept in place by a four ball detents connected to the push button, which presses against the walls of the socket. The sling swivel can quickly be taken on and off by pushing the QD button, which retracts the ball detents. The flush cup sockets can be either rotating or non rotating. Flush cups can be mounted to a long gun in various ways, for instance by drilling a hole in the stock and screwing in flush cup socket, or by using an adapter to other mounting standards such as Picatinny or M-LOK. | https://en.wikipedia.org/wiki?curid=54053141 | 450,318 |
Bitplane is a provider of software for 3D and 4D image analysis for the life sciences. Founded in December 1992, operates out of three offices in Zürich, Switzerland, Belfast, United Kingdom, and South Windsor, Connecticut, United States. As confocal microscopes were first becoming commercially available, the founders of Bitplane, Marius Messerli, Karl-Hermann Fuchs, and Jürgen Holm, realised that there was no suitable way to visualize and analyze the images provided by this more modern equipment. While pursuing their research at the Institute for cell Biology at the ETH in Zurich the first productive version of Bitplane's core product, Imaris, was developed. A small community of users developed among the scientific collaborators of the founders and the company was created. The name Imaris derives from three words: "image" analysis, the primary function of the software, "Marius" the name of the innovator and co-founder, and finally, the "Personal Iris", the name of the hardware that initially enabled interactive 3D imaging. When Imaris was introduced to the market in 1993 it ran only on Silicon Graphics (SGI) workstations as at the time only these were capable to perform 3D volume rendering at a speed worthy of being deemed "interactive". With the appearance of OpenGL capable graphics boards in personal computers the company decided to port its software to Windows and Macintosh and released a first version for the personal computer in 2001. By the end of 1994, the software had sold in 30 labs in central Europe | https://en.wikipedia.org/wiki?curid=1740636 | 86,068 |
Ground carriage In addition, alternate airports must be available if an airport is closed due to bad weather or a system failure. For emergency landings outside of runways, unsuitable flooring or unpaved ground cannot absorb the high wheel loads. Therefore, the landing gear of heavy long-haul aircraft in emergency landing on unsuitable ground is often not extended, since it would otherwise sink into ground first and then bend or break off. The precursor of the aircraft ground carriage is the jettisonable or detachable landing gear, wherein the aircraft takes-off from a cart, which is then released and eventually lands on skids. It was used on all operational examples of the Messerschmitt Me 163B "Komet" with its jettisonable twin-wheel "dolly" main gear — its conventional arrangement included a semi-retractable tailwheel on the "Komet's" rear fuselage — and the first eight prototypes of the Arado Ar 234 "Blitz", which all used a jettisonable tricycle-gear arrangement "trolley" design. The glider Schleicher Ka 1, which was built in the 1950s, also had a droppable landing gear. A Sea Vampire Mk.21 landed with retracted landing gear on an aircraft carrier with flexible rubber decks for testing purposes. The idea of the aircraft ground carriage is finally related to the aircraft catapult, especially with the Electromagnetic Aircraft Launch System, which is currently under development | https://en.wikipedia.org/wiki?curid=44163019 | 225,159 |
Fantom (software) Fantom is a digital trading card software platform that extends the traditional trading card game on-line. The technology also supports digital trading cards swappable using near field communication protocols, and GSM-based interfaces such as the Bump application. In September 2017, Fantom introduced software solution HyperDash that proposes to solve VR gaming concept and built APEX Tournament game. | https://en.wikipedia.org/wiki?curid=34370000 | 230,005 |
Bent pin analysis The failure modes of a particular pin always include (a) open circuit due to corrosion or other non-bending failure, and at least one of the following if the pin is bendable: (b) bending to nothing, (c) bending to one neighboring pin, (d) bending to one neighboring pin and the shell, (e) bending two neighboring pins, (f) bending to two neighboring pins and the shell, and (g) bending to the shell. In bent pin analysis, as it is usually performed, failure modes of each pin are determined using a scaled drawing of the connector and its pins. The analyst considers each bendable pin, one at a time, and determines which neighboring pins (if any) the selected pin can reach if bent, and whether the selected bent pin can reach the shell. The analysis usually does not include failure modes in which a bent pin simultaneously touches more than one other pin or a pin and the shell. If the analysis requires failure rates, an approximation is usually made by assigning an average failure rate to each failure mode based on the overall connector failure rate and the number of pins. Since this approach relies on human judgment there can be errors in the conclusions. Even with a conservative approach to cover "worst case" outcomes of bending, concluding that a bent pin can reach another pin (or the shell) when that failure mode is physically impossible is just as much an error as concluding that a bent pin cannot reach another pin (or the shell) when that failure mode is in fact possible | https://en.wikipedia.org/wiki?curid=39992948 | 399,862 |
Audio crossover " Crossovers can also be classified based on the type of components used. A passive crossover splits up an audio signal after it is amplified by a single power amplifier, so that the amplified signal can be sent to two or more driver types, each of which represent different frequency ranges. These crossover are made entirely of passive components and circuitry; the term "passive" means that no additional power source is needed for the circuitry. A passive crossover just needs to be connected by wiring to the power amplifier signal. Passive crossovers are usually arranged in a Cauer topology to achieve a Butterworth filter effect. Passive filters use resistors combined with reactive components such as capacitors and inductors. Very high performance passive crossovers are likely to be more expensive than active crossovers since individual components capable of good performance at the high currents and voltages at which speaker systems are driven are hard to make. Inexpensive consumer electronics products, such as budget-priced Home theater in a box packages and low-cost boom boxes use lower quality passive crossovers. Expensive hi-fi speaker systems and receivers use higher quality passive crossovers, to obtain improved sound quality and lower distortion | https://en.wikipedia.org/wiki?curid=96692 | 381,286 |
Traité Élémentaire de Chimie Traité élémentaire de chimie (Elementary Treatise on Chemistry) is a textbook written by Antoine Lavoisier published in 1789 and translated into English by Robert Kerr in 1790 under the title Elements of Chemistry in a New Systematic Order containing All the Modern Discoveries. It is considered to be the first modern chemical textbook. The book defines an element as a single substance that can't be broken down by chemical analysis and from which all chemical compounds are formed, publishing his discovery that fermentation produces carbon dioxide (carbonic gas) and spirit of wine, saying that it is "more appropriately called by the Arabic word alcohol since it is formed from cider or fermented sugar as well as wine", and publishing the first chemical equation "grape must = carbonic acid + alcohol", calling this reaction "one of the most extraordinary in chemistry", noting "In these experiments, we have to assume that there is a true balance or equation between the elements of the compounds with which we start and those obtained at the end of the reaction." The book contains a list of 33 elements, only 23 of which are elements in the modern sense | https://en.wikipedia.org/wiki?curid=24232670 | 30,671 |
Alan Nunn May On 1 May 1946, he was sentenced to ten years' hard labour. He was released in late 1952, after serving six and a half years. May refused to define his actions as treason, claiming in a statement after his release from prison that he believed he had "acted rightly" and had acted as a spy because of being "wholeheartedly concerned with securing victory over Nazi Germany and Japan, and the furtherance of the development of the peaceful uses of atomic energy." Blacklisted from universities in Britain, Nunn May worked for a scientific instruments company, then in 1961 went to work at the University of Ghana, where he conducted research in solid-state physics and created a science museum. Nunn May's first name is sometimes spelled "Allan" with two L's, but the "Oxford Dictionary of National Biography" and the "Encyclopædia Britannica" both use "Alan". In 1953, Nunn May married Hilde Broda, ex-wife of Engelbert Broda. They had a son, and a stepson from Hilde's previous marriage. He returned to Cambridge in 1978, and died there in a hospital on 12 January 2003. Cause of death was pneumonia and pulmonary disease. A 2002 statement released after his death stated that he had no regrets about his spying activities. It was passed to "The Guardian" newspaper in 2003 having been dictated to a relative in late 2002. Nunn May's arrest and sentence in 1946 first showed publicly that the Soviet Union had obtained atomic secrets by espionage. His clearance by MI5 also led to American distrust of Britain, and the McMahon Act | https://en.wikipedia.org/wiki?curid=1260465 | 248,925 |
Synapsis One such surveillance mechanism is meiotic silencing that involves the transcriptional silencing of genes on asynapsed chromosomes. Any chromosome region, either in males or females, that is asynapsed is subject to meiotic silencing. ATR, BRCA1 and gammaH2AX localize to unsynapsed chromosomes at the pachytene stage of meiosis in human oocytes and this may lead to chromosome silencing. The DNA damage response protein TOPBP1 has also been identified as a crucial factor in meiotic sex chromosome silencing. DNA double-strand breaks appear to be initiation sites for meiotic silencing. In female "Drosophila melanogaster" fruit flies, meiotic chromosome synapsis occurs in the absence of recombination. Thus synapsis in "Drosophila" is independent of meiotic recombination, consistent with the view that synapsis is a precondition required for the initiation of meiotic recombination. Meiotic recombination is also unnecessary for homologous chromosome synapsis in the nematode "Caenorhabditis elegans". | https://en.wikipedia.org/wiki?curid=2991457 | 147,947 |
New England Biolabs The product delivers a one day, automatable genotyping workflow for a variety of applications in Agricultural biotechnology. In January 2020, NEB signed an agreement with ERS Genomics Limited that gave NEB rights to sell CRISPR/Cas9 tools and reagents, used for gene editing. developed a colorimetric loop-mediated isothermal amplification (LAMP) assay for research use. This assay can be used to test for the presence of virus through nucleic acid detection, returning results in only 30 minutes. In 2020, the LAMP method was one of several molecular tests used to detect RNA from SARS-CoV-2, a strain of coronavirus that causes COVID-19. In February, NEB worked with the Wuhan Institute of Virology and the Chinese Academy of Sciences to test a method of identifying SARS-CoV-2 virus. The company runs free scientific databases. REBASE, the restriction enzyme database, contains the details of commercial and research endonucleases. In 2011 the company founded Polbase, an online database which provides information specifically about polymerases. Another free NEB database is InBase, an intein database, which includes the Intein Registry and information about each intein. In 2001, NEB co-founded the marine DNA library Ocean Genome Legacy (OGL), which according to the "Boston Globe", “catalogues samples of organisms from all over the world, to be made available to scientists for research”. Though originally located on the NEB campus, OGLF relocated to the Nahant campus of Northeastern University in 2014 | https://en.wikipedia.org/wiki?curid=9096236 | 14,776 |
Anti-pattern An anti-pattern is a common response to a recurring problem that is usually ineffective and risks being highly counterproductive. The term, coined in 1995 by Andrew Koenig, was inspired by a book, "Design Patterns", which highlights a number of design patterns in software development that its authors considered to be highly reliable and effective. The term was popularized three years later by the book "AntiPatterns", which extended its use beyond the field of software design to refer informally to any commonly reinvented but bad solution to a problem. Examples include analysis paralysis, cargo cult programming, death march, groupthink and vendor lock-in. According to the authors of "Design Patterns", there must be at least two key elements present to formally distinguish an actual anti-pattern from a simple bad habit, bad practice, or bad idea: | https://en.wikipedia.org/wiki?curid=233956 | 226,807 |
IEEE 802.1aq Node 2 on the other hand is only on one shortest path in this service and only creates a single forwarding entry from node 7 to node 6 for packets in this service. Figure 3 only shows a single E-LAN service and only the tree from one of the members, however very large numbers of E-LAN services with membership from 2 to every node in the network can be supported by advertising the membership, computing the tandem behaviors, manufacturing the known multicast addresses and populating the FIBs. The only real limiting factors are the FIB table sizes and computational power of the individual devices both of which are growing yearly in leaps and bounds. 802.1aq takes IS-IS topology information augmented with service attachment (I-SID) information, does a series of computations and produces a forwarding table (filtering table) for unicast and multicast entries. The IS-IS extensions that carry the information required by 802.1aq are given in the isis-layer2 IETF document listed below. An implementation of 802.1aq will first modify the IS-IS hellos to include an NLPID (network layer protocol identifier) of 0xC01 in their Protocols-Supported Type-length-value (TLV) (type 129) which has been reserved for 802.1aq. The hellos also must include an MSTID (which gives the purpose of each VID) and finally each ECMT behavior must be assigned to a VID and exchanged in the hellos. The hellos would normally run untagged. Note that NLPID of IP is not required to form an adjacency for 802 | https://en.wikipedia.org/wiki?curid=23094504 | 131,303 |
DNA These binding proteins seem to stabilize single-stranded and protect it from forming stem-loops or being degraded by nucleases. In contrast, other proteins have evolved to bind to particular sequences. The most intensively studied of these are the various transcription factors, which are proteins that regulate transcription. Each transcription factor binds to one particular set of sequences and activates or inhibits the transcription of genes that have these sequences close to their promoters. The transcription factors do this in two ways. Firstly, they can bind the RNA polymerase responsible for transcription, either directly or through other mediator proteins; this locates the polymerase at the promoter and allows it to begin transcription. Alternatively, transcription factors can bind enzymes that modify the histones at the promoter. This changes the accessibility of the template to the polymerase. As these targets can occur throughout an organism's genome, changes in the activity of one type of transcription factor can affect thousands of genes. Consequently, these proteins are often the targets of the signal transduction processes that control responses to environmental changes or cellular differentiation and development. The specificity of these transcription factors' interactions with come from the proteins making multiple contacts to the edges of the bases, allowing them to "read" the sequence. Most of these base-interactions are made in the major groove, where the bases are most accessible | https://en.wikipedia.org/wiki?curid=7955 | 301,108 |
Epitranscriptome All these methods are based on the unique reaction between pseudouridine and N-cyclohexyl-N'-(2-morpholinoethyl)carbodiimide metho-p-toluenesulfonate (CMCT). The RNA to be analyzed is fragmented and incubated with CMCT. Even if CMCT can form covalent bonds with U, G and Ψ residues, only Ψ-CMC is resistant to alkaline hydrolysis (U-CMC and G-CMC get hydrolyzed). Next, reverse transcription is done to obtain a cDNA library, with the cDNAs terminating one nucleotide downstream the pseudouridine residue. Next generation sequencing of the cDNA library will indicate where the modified pseudouridine residue is located in the RNA. In order to do this, two cDNA libraries are prepared, one in which the RNA has undergone CMC treatment and the other one without CMC treatment. Differences in the length of the reads between the two libraries will indicate where the Ψ residues are. Another method is called CeU-Seq, which uses a biotinylated derivative of CMCT. This enables the purification and enrichment of biotinylated transcripts (transcripts modified with pseudouridine) with streptavidin columns, therefore reducing the library size and increasing sensitivity. Other pseudouridine detection methods include site-specific cleavage and radioactive-labeling followed by ligation-assisted extraction and thin-layer chromatography (SCARLET) and mass spectrometry. Ribosomal RNA, or rRNA, forms the nucleic acid component of ribosomes | https://en.wikipedia.org/wiki?curid=41719778 | 163,779 |
GCV Infantry Fighting Vehicle On 25 August the Army retracted its request for proposals after the red team assembled in May recommended that the Army either upgrade the existing ground vehicle fleet or rewrite the requirements. The Technology Development Phase (or Milestone A) was to begin with the award of up to three vehicle contracts awarded in late Fiscal Year 2010 under the Technology Development Phase Contract. A Preliminary Design Review would follow in mid FY 2012. The U.S. military planned to spend $7.6 billion during Milestone A. The Engineering and Manufacturing Development Phase (or Milestone B) was to begin with two prototype development contracts awarded in the beginning of Fiscal Year 2013 under the Engineering & Manufacturing Development Contract. Shortly thereafter, an Interim Critical Design Review would follow in Mid-FY 2013. After a nearly two-year manufacturing period the first prototypes would be manufactured Mid-FY 2015 after which a Critical Design Review and a Production Readiness Review would occur in FY 2015 and FY 2016 respectively. The Low Rate Initial Production Phase (or Milestone C) was to begin with a low-rate production contract awarded in mid Fiscal Year 2016 under the Low Rate Initial Production (LRIP) contract. Less than two years after the contract award LRIP would begin. After more testing a battalion-sized team would be attained in FY 2018 followed by a brigade-sized arsenal in FY 2019. If a Full-Rate Production Decision was attained, full-rate production would begin. The U.S | https://en.wikipedia.org/wiki?curid=26520670 | 228,304 |
Frank-Kamenetskii theory In combustion, explains the thermal explosion of a homogeneous mixture of reactants, kept inside a closed vessel with constant temperature walls. It is named after a Russian scientist David A. Frank-Kamenetskii, who along with Nikolay Semenov developed the theory in the 1930s. Consider a vessel maintained at a constant temperature formula_1, containing a homogeneous reacting mixture. Let the characteristic size of the vessel be formula_2. Since the mixture is homogeneous, the density formula_3 is constant. During the initial period of ignition, the consumption of reactant concentration is negligible (see formula_4 and formula_5 below), thus the explosion is governed only by the energy equation. Assuming a one-step global reaction formula_6, where formula_7 is the amount of heat released per unit mass of fuel consumed, and reaction rate governed by Arrhenius law, the energy equation becomes where The non-dimensional activation energy formula_16 and the heat-release parameter formula_17 are The characteristic heat conduction time across the vessel is formula_19, the characteristic fuel consumption time is formula_20 and the characteristic explosion/ignition time is formula_21. Note should be made that in combustion process, typically formula_22 so that formula_23. Therefore, formula_24, i.e., the fuel is consumed at much longer times when compared with ignition time, the fuel consumption is essentially negligible to study ignition/explosion | https://en.wikipedia.org/wiki?curid=54055676 | 337,123 |
Sodium bicarbonate rocket A sodium bicarbonate rocket (sometimes called an Alka-Seltzer rocket) is a model rocket fashioned from a 35mm film canister and propelled by the pressure of a gas, often carbon dioxide, generated from the reaction of an acid with sodium bicarbonate. Sodium bicarbonate rockets are often used in science classes to demonstrate principles of chemistry and physics. In the experiment, a film canister is filled with water, an effervescent tablet (commonly Alka-Seltzer) is added and the canister tightly sealed. After a short time, the pressure of the carbon dioxide is great enough to cause the body of the canister to be launched into the air with a popping sound. The canister may be embellished with paper fins to resemble more closely a real rocket. Various experiments and lessons can center around the use of a bicarbonate rocket. For example, students are sometimes asked to experiment with the amounts of water and Alka-Seltzer to find the combination which propels the rocket the greatest distance. Alternatively they may derive equations to calculate the speed and velocity of the rocket from the distance it travels. In rocketry, a chemical reaction rapidly creates gas that is expelled in one direction from its container (the rocket engine); momentum forces the rocket in the opposite direction. The alka-seltzer rocket experiment demonstrates Newton's third law. The film canister rocket has a buildup of gas that wants to come out of the weakest spot making all the gas come out at once through the hole at the bottom | https://en.wikipedia.org/wiki?curid=14095613 | 80,858 |
Odile Eisenstein is a theoretical chemist who specializes in modelling the structure and reactivity of transition metals and lanthanide complexes. She is currently the equivalent of an Emeritus Professor at the Institut Charles Gerhardt Montpellier, équipe CTMM at Montpellier 2 University. She has been a member of the French Academy of Sciences since 2013. In 1977, attended University of Paris-Sud where she earned a Ph.D in chemistry with Nguyen Trong Anh and Lionel Salem. She obtained postdoctoral appointments with Jack D. Dunitz at ETH Zurich and Roald Hoffmann at Cornell University. Here, she did work on the nature of transition metal-olefin bonding interactions. She began her independent career at the University of Michigan at Ann Arbor in 1982. | https://en.wikipedia.org/wiki?curid=50229084 | 52,495 |
Null move In game theory, a null move or pass is a decision by a player to not make a move when it is that player's turn to move. Even though null moves are against the rules of many games, they are often useful to consider when analyzing these games. Examples of this include the analysis of zugzwang (a situation in chess or other games in which a null move, if it were allowed, would be better than any other move), and the null-move heuristic in game tree analysis (a method of pruning game trees involving making a null move and then searching to a lower depth). The reason a reduced-depth null move is effective in game tree alpha-beta search reduction is that tactical threats tend to show up very quickly, in just one or two moves. If the opponent has no tactical threats revealed by null move search, the position may be good enough to exceed the best result obtainable in another branch of the tree (i.e. "beta"), so that no further search need be done from the current node, and the result from the null move can be returned as the search value. Even if the null move search value doesn't exceed beta, the returned value may set a higher floor on the valuation of the position than the present alpha, so more cutoffs will occur at descendant sibling nodes from the position. The underlying assumption is that at least some legal move available to the player on move at the node is better than no move at all | https://en.wikipedia.org/wiki?curid=4927933 | 506,675 |
Anaerobic digestion Acetate and hydrogen produced in the first stages can be used directly by methanogens. Other molecules, such as volatile fatty acids (VFAs) with a chain length greater than that of acetate must first be catabolised into compounds that can be directly used by methanogens. The biological process of acidogenesis results in further breakdown of the remaining components by acidogenic (fermentative) bacteria. Here, VFAs are created, along with ammonia, carbon dioxide, and hydrogen sulfide, as well as other byproducts. The process of acidogenesis is similar to the way milk sours. The third stage of anaerobic digestion is acetogenesis. Here, simple molecules created through the acidogenesis phase are further digested by acetogens to produce largely acetic acid, as well as carbon dioxide and hydrogen. The terminal stage of anaerobic digestion is the biological process of methanogenesis. Here, methanogens use the intermediate products of the preceding stages and convert them into methane, carbon dioxide, and water. These components make up the majority of the biogas emitted from the system. Methanogenesis is sensitive to both high and low pHs and occurs between pH 6.5 and pH 8. The remaining, indigestible material the microbes cannot use and any dead bacterial remains constitute the digestate. Anaerobic digesters can be designed and engineered to operate using a number of different configurations and can be categorized into batch vs. continuous process mode, mesophilic vs. thermophilic temperature conditions, high vs | https://en.wikipedia.org/wiki?curid=1545608 | 97,621 |
Duct (flow) However, as it often replaces hard ductwork, it is easy to perceive it simply as a duct. Usually made of polyester material, fabric ducts can provide a more even distribution and blending of the conditioned air in a given space than a conventional duct system. They may also be manufactured with vents or orifices. Fabric ducts are available in various colours, with options for silk screening or other forms of decoration, or in porous (air-permeable) and non-porous fabric. The determination which fabric is appropriate (i.e. air-permeable or not) can be made by considering if the application would require an insulated metal duct. If so, an air-permeable fabric is recommended because it will not commonly create condensation on its surface and can therefore be used where air is supplied below the dew point. Material that eliminates moisture may be healthier for the occupants. It can also be treated with an anti-microbial agent to inhibit bacterial growth. Porous material also tends to require less maintenance as it repels dust and other airborne contaminants. Fabric made of more than 50% recycled material is also available, allowing it to be certified as green product. The material can also be fire retardant, which means that the fabric can still burn, but will extinguish when the heat source is removed. Fabric ducts are not rated for use in ceilings or concealed attic spaces. However, products for use in raised floor applications are available | https://en.wikipedia.org/wiki?curid=6280965 | 386,427 |
Cre recombinase The effect of the two-domain structure is to form a C-shaped clamp that grasps the DNA from opposite sides. The active site of the Cre enzyme consists of the conserved catalytic triad residues Arg 173, His 289, Arg 292 as well as the conserved nucleophilic residues Tyr 324 and Trp 315. Unlike some recombinase enzymes such as Flp recombinase, Cre does not form a shared active site between separate subunits and all the residues that contribute to the active site are found on a single subunit. Consequently, when two Cre molecules bind at a single loxP site two active sites are present. Cre mediated recombination requires the formation of a synapse in which two Cre-LoxP complexes associate to form what is known as the synapse tetramer in which 4 distinct active sites are present. Tyr 324 acts as a nucleophile to form a covalent 3’-phosphotyrosine linkage to the DNA substrate. The scissile phosphate (phosphate targeted for nucleophilic attack at the cleavage site) is coordinated by the side chains of the 3 amino acid residues of the catalytic triad (Arg 173, His 289 & Trp 315). The indole nitrogen of tryptophan 315 also forms a hydrogen bond to this scissile phosphate. (n.b A Histidine occupies this site in other tyrosine recombinase family members and performs the same function). This reaction cleaves the DNA and frees a 5’ hydroxyl group. This process occurs in the active site of two out of the four recombinase subunits present at the synapse tetramer | https://en.wikipedia.org/wiki?curid=4468576 | 57,540 |
Signal transition Signal transition, when referring to the modulation of a carrier signal, is a change from one significant condition to another. Examples of signal transitions are a change from one electric current, voltage, or power level to another; a change from one optical power level to another; a phase shift; or a change from one frequency or wavelength to another. Signal transitions are used to create signals that represent information, such as "0" and "1" or "mark" and "space". | https://en.wikipedia.org/wiki?curid=41707 | 303,977 |
John von Neumann Anderson: "You know, Herb, Johnny can do calculations in his head ten times as fast as I can! And I can do them ten times as fast as you can, Herb, so you can see how impressive Johnny is!" Halmos recounts a story told by Nicholas Metropolis, concerning the speed of von Neumann's calculations, when somebody asked von Neumann to solve the famous fly puzzle: Eugene Wigner told a similar story, only with a swallow instead of a fly, and says it was Max Born who posed the question to von Neumann in the 1920s. Von Neumann was also noted for his eidetic memory (sometimes called photographic memory). Herman Goldstine wrote: Von Neumann was reportedly able to memorize the pages of telephone directories. He entertained friends by asking them to randomly call out page numbers; he then recited the names, addresses and numbers therein. "It seems fair to say that if the influence of a scientist is interpreted broadly enough to include impact on fields beyond science proper, then was probably the most influential mathematician who ever lived," wrote Miklós Rédei in "John von Neumann: Selected Letters". James Glimm wrote: "he is regarded as one of the giants of modern mathematics" | https://en.wikipedia.org/wiki?curid=15942 | 363,853 |
International Institute of Refrigeration Recent publications include the IIR technical guide on the application of "CO2 as a Refrigerant " by Dr Andy Pearson (2014), the "Handbook on indirect refrigeration and heat pump systems", editor, Åke Melinder (2015) and "Technological options for retail refrigeration" by experts at London South Bank University (2018). The IIR produces an electronic monthly newsletter that features news and updates on the refrigeration sector: regulation, events, economic data, monitoring, technological progress, etc. It provides a detailed overview of the general developments within the sector worldwide and as acts a regular information tool for readers. The Institute produces a monthly "International Journal of Refrigeration" that is published by Elsevier. The "International Journal of Refrigeration" is the reference journal in the refrigeration field. It is now ranked 22 out of 130 mechanical engineering journals, and ranked 12 out of 58 thermodynamics journals. It is practical for all those wanting to keep abreast of research and industrial news in all fields of refrigeration including air-conditioning, heat-pump, refrigerated storage and transport. The IIR holds international conferences and congresses on key themes which include: Once every four years the IIR holds overarching International Congress of Refrigeration (ICR) encompassing all refrigeration fields which unites major stakeholders active in the refrigeration industry | https://en.wikipedia.org/wiki?curid=32484563 | 281,513 |
Bode plot If a simple "yes" or "no" on the stability issue is all that is needed, the amplifier is stable if "f" < "f". This criterion is sufficient to predict stability only for amplifiers satisfying some restrictions on their pole and zero positions (minimum phase systems). Although these restrictions usually are met, if they are not another method must be used, such as the Nyquist plot. Optimal gain and phase margins may be computed using Nevanlinna–Pick interpolation theory. Figures 6 and 7 illustrate the gain behavior and terminology. For a three-pole amplifier, Figure 6 compares the for the gain without feedback (the "open-loop" gain) "A" with the gain with feedback "A" (the "closed-loop" gain). See negative feedback amplifier for more detail. In this example, "A" = 100 dB at low frequencies, and 1 / β = 58 dB. At low frequencies, "A" ≈ 58 dB as well. Because the open-loop gain "A" is plotted and not the product β "A", the condition "A" = 1 / β decides "f". The feedback gain at low frequencies and for large "A" is "A" ≈ 1 / β (look at the formula for the feedback gain at the beginning of this section for the case of large gain "A"), so an equivalent way to find "f" is to look where the feedback gain intersects the open-loop gain. (Frequency "f" is needed later to find the phase margin.) Near this crossover of the two gains at "f", the Barkhausen criteria are almost satisfied in this example, and the feedback amplifier exhibits a massive peak in gain (it would be infinity if β "A" = −1) | https://en.wikipedia.org/wiki?curid=155562 | 133,884 |
Bunding Bunding, also called a bund wall, is a constructed retaining wall around storage "where potentially polluting substances are handled, processed or stored, for the purposes of containing any unintended escape of material from that area until such time as a remedial action can be taken." The term can also refer to dikes, but it is frequently used to describe liquid containment facilities that prevent leaks and spillage from tanks and pipes, though sometimes any barrier is referred to as bunding. Frequently, the liquids in these tanks and pipes are toxic, and bunding is used to prevent the liquid from causing damage (either by force or its chemistry). If a large tank has a catastrophic failure, the liquid alone can cause extensive damage. If built properly, bunding is large enough and strong enough to contain the contents of an entire tank, though regulations may require it to be up to a third larger. When multiple tanks share a bund, the capacity is based on the largest tank. One of the most common designs for large tanks is a concrete or masonry wall around the tank with a concrete floor. Concrete works very well for many liquids, but it is unsuitable for some applications like containing strong acids. Using earth berms for bunding is not recommended for most situations, though liners can be used to decrease permeability. Smaller tanks often use containers made of steel or plastic. The material used depends on cost, the chemical properties of the liquid and its density | https://en.wikipedia.org/wiki?curid=3755953 | 310,811 |
Panama Canal Almost all major cruise ships have more than 33 tons per passenger; the rule of thumb for cruise line comfort is generally given as a minimum of 40 tons per passenger. Most other types of vessel pay a toll per PC/UMS net ton, in which one "ton" is actually a volume of . (The calculation of tonnage for commercial vessels is quite complex.) , this toll is US$5.25 per ton for the first 10,000 tons, US$5.14 per ton for the next 10,000 tons, and US$5.06 per ton thereafter. As with container ships, reduced tolls are charged for freight ships "in ballast", $4.19, $4.12, $4.05 respectively. On 1 April 2016, a more complicated toll system was introduced, having the neopanamax locks at a higher rate in some cases, natural gas transport as a new separate category and other changes. As of October 1, 2017, there are modified tolls and categories of tolls in effect. Small (less than 125 ft) vessels up to 583 PC/UMS net tons when carrying passengers or cargo, or up to 735 PC/UMS net tons when in ballast, or up to 1,048 fully loaded displacement tons, are assessed minimum tolls based upon their length overall, according to the following table (as of 29 April 2015): Morgan Adams of Los Angeles, California, holds the distinction of paying the first toll received by the United States Government for the use of the by a pleasure boat. His boat "Lasata" passed through the Zone on August 14, 1914. The crossing occurred during a 6,000-mile sea voyage from Jacksonville, Florida, to Los Angeles in 1914 | https://en.wikipedia.org/wiki?curid=24849 | 364,230 |
E-Verify (C) The South Carolina Department of Employment and Workforce shall provide private employers with technical advice and electronic access to the federal work authorization program's website for the sole purpose of registering and participating in the program. (D) Private employers shall employ provisionally a new employee until the new employee's work authorization has been verified pursuant to this section. A private employer shall submit a new employee's name and information for verification even if the new employee's employment is terminated less than three business days after becoming employed. If a new employee's work authorization is not verified by the federal work authorization program, a private employer must not employ, continue to employ, or reemploy the new employee. (E) To assist private employers in understanding the requirements of this chapter, the director shall send written notice of the requirements of this section to all South Carolina employers, and shall publish the information contained in the notice on its website. Nothing in this section shall create a legal requirement that any private employer receive actual notice of the requirements of this chapter through written notice from the director, nor create any legal defense for failure to receive notice. (F) If a private employer is a contractor, the private employer shall maintain the contact phone numbers of all subcontractors and sub-subcontractors performing services for the private employer | https://en.wikipedia.org/wiki?curid=14041658 | 501,242 |
Guerrilla marketing They pasted several post-it with the shapes of some characters from different video games. Those images were placed as if they were billboards on the streets. “Wii not forget”, the name of the campaign, and a brief explanation of it, were the words written on the post-its. In some cases, some street marketing may incite the ire of local authorities; such was the case in Houston, Texas, when BMW's ad agency (Street Factory Media in Minneapolis)attached a replication, made from Styrofoam, of a Mini-Cooper to the side of a downtown building. For the cost of a small city-issued fine, the company received front page advertising on the Houston Chronicle. Sony Ericsson used an undercover campaign in 2002 when they hired 60 actors in ten major cities and had them accost strangers and ask them: "Would you mind taking my picture?" The actor then handed the target a brand new picture phone while talking about how cool the new device was. "And thus an act of civility was converted into a branding event. is not just exclusive to small companies. For big companies it is a high risk, high reward strategy. When successful it can capture even more market share, but if it fails it can damage the company’s brand image. One successful guerrilla marketing campaign is the Coca-Cola ‘Happiness Machine”. In January 2010, Coca-Cola, with the help of Definition 6, filmed a reaction video of a Coke vending machine dispensing ‘doses’ of happiness to unsuspecting students in St. John's University | https://en.wikipedia.org/wiki?curid=177546 | 499,121 |
Diving cylinder On technical dives where a direct ascent is either impossible (due to overhead obstructions) or dangerous (due to the requirement to make decompression stops), divers plan larger margins of safety. The simplest method uses the rule of thirds: one third of the gas supply is planned for the outward journey, one third is for the return journey and one third is a safety reserve. Some training agencies teach the concept of minimum gas, rock bottom gas management or critical pressures which allows a diver to calculate an acceptable reserve to get two divers to the surface in an emergency from any point in the planned dive profile. Professional divers may be required by legislation or industry codes of practice to carry sufficient reserve gas to enable them to reach a place of safety, such as the surface, or a diving bell, based on the planned dive profile. This reserve gas is usually required to be carried as an independent emergency gas supply (EGS), also known as a bailout cylinder, set or bottle. This usually also applies to professional divers using surface-supplied diving equipment. The density of air at sea level and 15 °C is approximately 1.225 kg/m. Most full-sized diving cylinders used for open circuit scuba hold more than of air when full, and as the air is used, the buoyancy of the cylinder increases by the weight removed. The decrease in external volume of the cylinder due to reduction of internal pressure is relatively small, and can be ignored for practical purposes | https://en.wikipedia.org/wiki?curid=460321 | 339,433 |
History of pharmacy in the United States Of the few apothecaries imported from Europe, those of Jesuit training had a long-felt impact in both New Spain and New France; so great was Jesuit involvement in "care of the sick" in their foreign missions, in fact, they sought and received a papal exemption from the ban on clerics serving in medical roles. Two dedicated "pharmacopoles or apothecary brethren" Jesuits are listed under the heading "Missions of North America in New France" in Society of Jesus personnel records for the "Province of France at the End of the Year 1749." Jesuit contributions, especially in translating Native American ethnobotany into medicines for European use, were highly influential as pharmacy developed in North America. Pharmacist Ambrose Hunsberger, in his sweeping introduction covering pharmacy's development in the United States prior to the events discussed in his 1923 article on Prohibition's impact, "The Practice of Pharmacy Under the Volstead Act," described pharmacy before its organization (which he places around 1821) in terms that evoke the snake oil salesmen and medicine shows that hit every town, hamlet and village in the country: "...the disorganized system of hawking medicinal remedies which prevailed throughout our thinly populated country | https://en.wikipedia.org/wiki?curid=34631752 | 62,224 |
Economizer When the outside air is both sufficiently cool and sufficiently dry (depending on the climate) the amount of enthalpy in the air is acceptable and no additional conditioning of it is needed; this portion of the air-side economizer control scheme is called "free cooling". Air-side economizers can reduce HVAC energy costs in cold and temperate climates while also potentially improving indoor air quality, but are most often not appropriate in hot and humid climates. With the appropriate controls, economizers can be used in climates which experience various weather systems. For information on how economizers and other controls can affect energy efficiency and indoor air quality in buildings, see the US Environmental Protection Agency report, "Energy Cost and IAQ Performance of Ventilation Systems and Controls Study." When the outside air's dry- and wet-bulb temperatures are low enough, a water-side economizer can use water cooled by a wet cooling tower or a dry cooler (also called a fluid cooler) to cool buildings without operating a chiller. They are historically known as the "strainer cycle", but the water-side economizer is not a true thermodynamic cycle. Also, instead of passing the cooling tower water through a strainer and then to the cooling coils, which causes fouling, more often a plate-and-frame heat exchanger is inserted between the cooling tower and chilled water loops | https://en.wikipedia.org/wiki?curid=4655742 | 387,340 |
Epitranscriptome Pseudouridine increases the stability of the modified RNA by making the sugar-phosphate backbone more rigid and by facilitating base stacking interactions (pseudouridine contains an extra hydrogen bond donor). When it comes to Watson-Crick base pair interactions, the pseudouridine-adenosine base pair is more stable than the uridine-adenosine base pair; therefore, pseudouridine increases stability. Apart from increasing RNA stability, this modification is also involved in regulation of translation. All eukaryotic stop codons contain one uridine (UAA, UGA and UGA); conversion of this uridine to pseudouridine results in suppression of translational termination and generation of unexpected sense codons. The artificial process of pseudouridylation has an effect on the function of mRNA: it changes the genetic code by making non-canonical base pairing possible in the ribosome decoding center. Pseudouridylation reactions are catalyzed by enzymes that contain the pseudouridine synthase domain; 13 such enzymes have been identified in humans, which are called pseudouridine syntheses (PUS). These enzymes can be either RNA-dependent or RNA-independent depending on whether a small RNA is needed to guide the enzyme to its target or not. Additionally, different PUS enzymes work in different cell compartments. For instance, PUS4 (also known as TruB pseudouridine synthase family member 1, TRUB1) and PUS7, which are responsible for most of the mRNA pseudouridylation, are located in the nucleus or the cytoplasm | https://en.wikipedia.org/wiki?curid=41719778 | 20,543 |
Point mutation RIP causes G:C to A:T transition mutations within repeats, however, the mechanism that detects the repeated sequences is unknown. RID is the only known protein essential for RIP. It is a DNA methyltransferease-like protein, that when mutated or knocked out results in loss of RIP. Deletion of the "rid" homolog in "Aspergillus nidulans", "dmtA", results in loss of fertility while deletion of the "rid" homolog in "Ascobolus immersens", "masc1", results in fertility defects and loss of methylation induced premeiotically (MIP). RIP is believed to have evolved as a defense mechanism against transposable elements, which resemble parasites by invading and multiplying within the genome. RIP creates multiple missense and nonsense mutations in the coding sequence. This hypermutation of G-C to A-T in repetitive sequences eliminates functional gene products of the sequence (if there were any to begin with). In addition, many of the C-bearing nucleotides become methylated, thus decreasing transcription. Because RIP is so efficient at detecting and mutating repeats, fungal biologists often use it as a tool for mutagenesis. A second copy of a single-copy gene is first transformed into the genome. The fungus must then mate and go through its sexual cycle to activate the RIP machinery. Many different mutations within the duplicated gene are obtained from even a single fertilization event so that inactivated alleles, usually due to nonsense mutations, as well as alleles containing missense mutations can be obtained | https://en.wikipedia.org/wiki?curid=611074 | 142,311 |
Radical cyclization reactions are organic chemical transformations that yield cyclic products through radical intermediates. They usually proceed in three basic steps: selective radical generation, radical cyclization, and conversion of the cyclized radical to product. reactions produce mono- or polycyclic products through the action of radical intermediates. Because they are intramolecular transformations, they are often very rapid and selective. Selective radical generation can be achieved at carbons bound to a variety of functional groups, and reagents used to effect radical generation are numerous. The radical cyclization step usually involves the attack of a radical on a multiple bond. After this step occurs, the resulting cyclized radicals are quenched through the action of a radical scavenger, a fragmentation process, or an electron-transfer reaction. Five- and six-membered rings are the most common products; formation of smaller and larger rings is rarely observed. Three conditions must be met for an efficient radical cyclization to take place: Advantages: because radical intermediates are not charged species, reaction conditions are often mild and functional group tolerance is high and orthogonal to that of many polar processes | https://en.wikipedia.org/wiki?curid=27347213 | 71,460 |
Beltrami flow , Introduce the following separation of variables then the equation satisfied by formula_18 becomes obtained the solution in Cartesian coordinates for formula_18 in 1963, The generalized satisfies the condition which is less restrictive than the Beltrami condition formula_23. Unlike the normal Beltrami flows, the generalized can be studied for planar and axisymmetric flows. For steady generalized Beltrami flow, we have formula_24 and since it is also planar we have formula_25. Introduce the stream function Integration of formula_22 gives formula_28. So, complete solution is possible if it satisfies all the following three equations A special case is considered when the flow field has uniform vorticity formula_30. Wang (1991) gave the generalized solution as assuming a linear function for formula_32. Substituting this into the vorticity equation and introducing the separation of variables formula_33 with the separating constant formula_34 results in The solution obtained for different choices of formula_36 can be interpreted differently, for example, formula_37 represents a flow downstream a uniform grid, formula_38 represents a flow created by a stretching plate, formula_39 represents a flow into a corner, formula_40 represents an Asymptotic suction profile etc. Here, G. I. Taylor gave the solution for a special case where formula_42, where formula_43 is a constant in 1923 | https://en.wikipedia.org/wiki?curid=53977093 | 45,508 |
Nuvistor The nuvistor is a type of vacuum tube announced by RCA in 1959. Most nuvistors are basically thimble-shaped, but somewhat smaller than a thimble, and much smaller than conventional tubes of the day, almost approaching the compactness of early discrete transistor casings. Triodes and a few tetrodes were made. The tube is made entirely of metal and ceramic. Making nuvistors requires special equipment, since there is no intubation to pump gases out of the envelope. Instead, the entire structure is assembled, inserted into its metal envelope, sealed and processed in a large vacuum chamber with simple robotic devices. Nuvistors are among the highest performing small signal receiving tubes. They feature excellent VHF and UHF performance plus low noise figures, and were widely used throughout the 1960s in television sets (beginning with RCA's "New Vista" line of color sets in 1961 with the CTC-11 chassis), radio and high-fidelity equipment primarily in RF sections, and oscilloscopes. They competed with the solid state revolution, and along with GE's Compactron, probably held it at bay for a few years. RCA discontinued their use in television tuners for its product line in late 1971. One famous application was in the Ampex MR-70, a costly studio tape recorder whose entire electronics section was based on nuvistors. Another limited application of this very small tube was in studio-grade microphones from that era, the AKG/Norelco C12a, which employed the 7586, being a good example | https://en.wikipedia.org/wiki?curid=22111 | 396,169 |
Business process automation (BPA), also known as business automation or digital transformation, is the technology-enabled automation of complex business processes. It can streamline a business for simplicity, achieve digital transformation, increase service quality, improve service delivery or contain costs. It consists of integrating applications, restructuring labor resources and using software applications throughout the organization. Robotic process automation is an emerging field within BPA and uses artificial intelligence. BPAs can be implemented in a number of business areas including marketing, sales and workflow. Toolsets vary in sophistication, but there is an increasing trend towards the use of artificial intelligence technologies that can understand natural language and unstructured data sets, interact with human beings, and adapt to new types of problems without human-guided training. BPA providers tend to focus on different industry sectors but their underlying approach tends to be similar in that they will attempt to provide the shortest route to automation by exploiting the user interface layer rather than going deeply into the application code or databases sitting behind them. They also simplify their own interface to the extent that these tools can be used directly by non-technically qualified staff. The main advantage of these toolsets is therefore their speed of deployment, the drawback is that it brings yet another IT supplier to the organization. The market is, however, evolving in this area | https://en.wikipedia.org/wiki?curid=1155664 | 217,945 |
Direct memory access Where a peripheral can become bus master, it can directly write to system memory without involvement of the CPU, providing memory address and control signals as required. Some measure must be provided to put the processor into a hold condition so that bus contention does not occur. In "burst mode", an entire block of data is transferred in one contiguous sequence. Once the DMA controller is granted access to the system bus by the CPU, it transfers all bytes of data in the data block before releasing control of the system buses back to the CPU, but renders the CPU inactive for relatively long periods of time. The mode is also called "Block Transfer Mode". The "cycle stealing mode" is used in systems in which the CPU should not be disabled for the length of time needed for burst transfer modes. In the cycle stealing mode, the DMA controller obtains access to the system bus the same way as in burst mode, using "BR (Bus Request)" and "BG (Bus Grant)" signals, which are the two signals controlling the interface between the CPU and the DMA controller. However, in cycle stealing mode, after one byte of data transfer, the control of the system bus is deasserted to the CPU via BG. It is then continually requested again via BR, transferring one byte of data per request, until the entire block of data has been transferred. By continually obtaining and releasing the control of the system bus, the DMA controller essentially interleaves instruction and data transfers | https://en.wikipedia.org/wiki?curid=57717 | 380,543 |
Information Processing Letters is a peer reviewed scientific journal in the field of computer science, published by Elsevier. The aim of the journal is to enable fast dissemination of results in the field of information processing in the form of short papers. Submissions are limited to nine double-spaced pages. Both theoretical and experimental research is covered. | https://en.wikipedia.org/wiki?curid=26374420 | 139,826 |
Transfection Because the term transformation had another sense in animal cell biology (a genetic change allowing long-term propagation in culture, or acquisition of properties typical of cancer cells), the term transfection acquired, for animal cells, its present meaning of a change in cell properties caused by introduction of DNA. There are various methods of introducing foreign DNA into a eukaryotic cell: some rely on physical treatment (electroporation, cell squeezing, nanoparticles, magnetofection); others rely on chemical materials or biological particles (viruses) that are used as carriers. Gene delivery is, for example, one of the steps necessary for gene therapy and the genetic modification of crops. There are many different methods of gene delivery developed for various types of cells and tissues, from bacterial to mammalian. Generally, the methods can be divided into two categories: non-viral and viral. Non-viral methods include physical methods such as electroporation, microinjection, gene gun, impalefection, hydrostatic pressure, continuous infusion, and sonication and chemical, such as lipofection, which is a lipid-mediated DNA-transfection process utilizing liposome vectors. It can also include the use of polymeric gene carriers (polyplexes). Virus mediated gene delivery utilizes the ability of a virus to inject its DNA inside a host cell. A gene that is intended for delivery is packaged into a replication-deficient viral particle | https://en.wikipedia.org/wiki?curid=619632 | 142,379 |
Royal Military Academy, Woolwich Practical teaching continued to be given in the working context of the Arsenal. In 1810, military cadets of the East India Company, who had previously been educated at the Academy, were moved to a new college at Addiscombe. During the years that followed the status of the cadets changed: rather than being considered (albeit junior) military personnel, as had previously been the case, they were removed from the muster roll and they (or their parents) began to be charged fees for attendance. In this way the Academy took on something of the ethos of an English public school. In 1844 the Academy was described by Edward Mogg as accommodating: Following the demise of the Board of Ordnance in the wake of the Crimean War the Academy was inspected by a commission which recommended changes: the minimum age for cadets was raised to fifteen and more specialist training was added. As part of these reforms the Academy complex was enlarged in the 1860s, with a view to accommodating all cadets on the same site (although some would remain in the Arsenal through to the 1880s): the frontage was extended with the addition of new pavilions at either end, in similar style to Wyatt's work but in red brick rather than yellow; William Jervois was the architect. These contained new classrooms, with accommodation provided in similar new blocks behind. Sports facilities were also added along with gun batteries for training. In 1873 Wyatt's central block had to be entirely rebuilt following a devastating fire | https://en.wikipedia.org/wiki?curid=356732 | 308,984 |
Remote visual inspection Remote Visual Inspection or Remote Digital Video Inspection, also known as RVI or RDVI, is a form of visual inspection which uses visual aids including video technology to allow an inspector to look at objects and materials from a distance because the objects are inaccessible or are in dangerous environments. RVI is also a specialty branch of nondestructive testing (NDT). Technologies include, but not limited to, rigid or flexible borescopes, videoscopes, fiberscopes, push cameras, pan/tilt/zoom cameras and robotic crawlers. Remote are commonly used where distance, angle of view and limited lighting may impair direct visual examination or where access is limited by time, financial constraints or atmospheric hazards. RVI/RDVI is commonly used as a predictive maintenance or regularly scheduled maintenance tool to assess the "health" and operability of fixed and portable assets. RVI/RDVI enables greater inspection coverage, inspection repeatability and data comparison. The "remote" portion of RVI/RDVI refers to the characterization of the operator not entering the inspection area due to physical size constraints or potential safety issues related to the inspection environment. Typical applications for RVI include: | https://en.wikipedia.org/wiki?curid=25113859 | 423,523 |
Delmar Gardens and Buster Keaton, boxers John L. Sullivan and Jack Dempsey, and the legendary race horse Dan Patch. Lon Chaney, Sr. was appearing at Delmar Theater in 1905 when he rescued a beautiful 16-year-old songbird from a flooded basement dressing room. Her name was Cleva Crieghton, and after a whirlwind courtship the couple married in Oklahoma City. Whether or not they took advantage of the romantic Delmar Garden floating chapel is lost to time. In 1904 Tom Mix performed at with the Oklahoma Cavalry Band, where he met and became engaged to Kitty Jewel Perrine, daughter of the Perrine Hotel owner where Tom was renting a room. was adjacent to Wheeler Park and the city's first zoo. On May 13, 1902, James B. Wheeler deeded land to the City of Oklahoma City, roughly from the Frisco railroad tracks (today's I-40 realignment) to the Canadian River, "to be perpetually used by party of second part as a public park for the free use and benefit of the citizens of Oklahoma City." As part of the conveyance, the park's name would never be changed. The entire complex, however, fronted a prairie river, and not the Atlantic Ocean. Swarms of mosquitoes that accompanied the river's annual flooding contributed to Delmar Gardens' demise, and the advent of prohibition was the death blow. It closed in 1910, and the buildings were razed the following year | https://en.wikipedia.org/wiki?curid=26495520 | 337,729 |
LAVIS (software) LAVIS is a software tool created by the TOOL Corporation, Japan. LAVIS is a "layout visualisation platform". It supports a variety of formats such as GDSII, OASIS and LEF/DEF and can be used as a platform for common IC processes. | https://en.wikipedia.org/wiki?curid=31683389 | 206,587 |
Introduction to genetics However, if the alleles for a particular protein have different sequences and produce proteins that can't do their jobs, no melanin is produced and the person has white skin and hair (albinism). Genes are copied each time a cell divides into two new cells. The process that copies DNA is called DNA replication. It is through a similar process that a child inherits genes from its parents when a copy from the mother is mixed with a copy from the father. DNA can be copied very easily and accurately because each piece of DNA can direct the creation of a new copy of its information. This is because DNA is made of two strands that pair together like the two sides of a zipper. The nucleotides are in the center, like the teeth in the zipper, and pair up to hold the two strands together. Importantly, the four different sorts of nucleotides are different shapes, so for the strands to close up properly, an A nucleotide must go opposite a T nucleotide, and a G opposite a C. This exact pairing is called base pairing. When DNA is copied, the two strands of the old DNA are pulled apart by enzymes; then they pair up with new nucleotides and then close. This produces two new pieces of DNA, each containing one strand from the old DNA and one newly made strand. This process is not predictably perfect as proteins attach to a nucleotide while they are building and cause a change in the sequence of that gene. These changes in the DNA sequence are called mutations. Mutations produce new alleles of genes | https://en.wikipedia.org/wiki?curid=8406655 | 161,346 |
Cortactin (from ""cortical actin" binding protein") is a monomeric protein located in the cytoplasm of cells that can be activated by external stimuli to promote polymerization and rearrangement of the actin cytoskeleton, especially the actin cortex around the cellular periphery. It is present in all cell types. When activated, it will recruit Arp2/3 complex proteins to existing actin microfilaments, facilitating and stabilizing nucleation sites for actin branching. is important in promoting lamellipodia formation, invadopodia formation, cell migration, and endocytosis. In humans, cortactin is encoded by the "CTTN" gene on chromosome 11. is a thin, elongated monomer that consists of an amino-terminal acidic (NTA) region; 37-residue-long segments that are highly conserved among cortactin proteins of all species and repeated up to 6.5 times in tandem (“cortactin repeats”); a proline-rich region; and an SH3 domain. This basic structure is highly conserved among all species that express cortactin. is activated via phosphorylation, by tyrosine kinases or serine/threonine kinases, in response to extracellular signals like growth factors, adhesion sites, or pathogenic invasion of the epithelial layer. The SH3 domain of certain tyrosine kinases, such as the oncogene Src kinase, binds to cortactin's proline-rich region and phosphorylates it on Tyr421, Tyr466, and Tyr482. Once activated in this way, it can bind to filamentous actin (F-actin) with the fourth of its cortactin repeats | https://en.wikipedia.org/wiki?curid=7137955 | 153,056 |
Transatlantic flight 21 Maia", ("G-ADHK") which was a variant of the Short "C-Class" Empire flying-boat fitted with a trestle or pylon on the top of the fuselage to support the "Short S.20 Mercury"("G-ADHJ"). The first successful in-flight separation of the "Composite" was carried out on 6 February 1938, and the first transatlantic flight was made on 21 July 1938 from Foynes to Boucherville. "Mercury", piloted by Captain Don Bennett, separated from her carrier at 8 pm to continue what was to become the first commercial non-stop east-to-west transatlantic flight by a heavier-than-air machine. This initial journey took 20 hrs, 21 min at an average ground speed of . Another technology developed for the purpose of transatlantic commercial flight, was aerial refuelling. Sir Alan Cobham developed the "Grappled-line looped-hose" system to stimulate the possibility for long-range transoceanic commercial aircraft flights, and publicly demonstrated it for the first time in 1935. In the system the receiver aircraft trailed a steel cable which was then grappled by a line shot from the tanker. The line was then drawn back into the tanker where the receiver's cable was connected to the refueling hose. The receiver could then haul back in its cable bringing the hose to it. Once the hose was connected, the tanker climbed sufficiently above the receiver aircraft to allow the fuel to flow under gravity | https://en.wikipedia.org/wiki?curid=669724 | 244,362 |
Fischer–Tropsch process The plant modeled the full cycle of the GTL chemical process including the intake of pipeline gas, sulfur removal, steam methane reforming, syngas conditioning, and Fischer–Tropsch synthesis. In 2013 the first pilot plant was acquired by VNIIGAZ Gazprom LLC. In 2014 INFRA commissioned and operated on a continuous basis a new, larger scale full cycle Pilot Plant. It represents the second generation of INFRA's testing facility and is differentiated by a high degree of automation and extensive data gathering system. In 2015, INFRA built its own catalyst factory in Troitsk (Moscow, Russia). The catalyst factory has a capacity of over 15 tons per year, and produces the unique proprietary Fischer–Tropsch catalysts developed by the company's R&D division. In 2016, INFRA designed and built a modular, transportable GTL (gas-to-liquid) M100 plant for processing natural and associated gas into synthetic crude oil in Wharton (Texas, USA). The M100 plant is operating as a technology demonstration unit, R&D platform for catalyst refinement, and economic model to scale the Infra GTL process into larger and more efficient plants. In the United States and India, some coal-producing states have invested in Fischer–Tropsch plants. In Pennsylvania, Waste Management and Processors, Inc. was funded by the state to implement Fischer–Tropsch technology licensed from Shell and Sasol to convert so-called waste coal (leftovers from the mining process) into low-sulfur diesel fuel | https://en.wikipedia.org/wiki?curid=1284762 | 143,939 |
Dreambox It is based around an IBM STBx25xx Digital Set-Top Box Integrated Controller, featuring notably a 252 MHz PowerPC processor subsystem, hardware MPEG-2 video and audio decoding and smart card interfaces. The DM500 features 32 MB of RAM and 8 MB of NOR flash memory, of which 5 MB are used for read-only firmware (cramfs and squashfs filesystems), 256 kB by the boot loader and the rest by a writable jffs2 filesystem. It has the standard features of a free-to-air (FTA) satellite receiver, plus extensive Fast Ethernet networking connectivity and a single smart card reader. It does not feature a 7-segment LED display, normally found in other FTA decoders. Also has the ability to be used on Digital satellite, cable and terrestrial broadcasts (also known as DVB-S, DVB-C, DVB-T). The DM500+ model has 96 MB of RAM instead of 32, and 32 MB of NAND flash instead of 8 MB of NOR flash. This makes it similar to the DM600 PVR model. It is only available in DVB-S versions. The new DM500HD was announced in Cologne on May 26, 2009. The price will be between and . The DM 7020 is essentially an updated DM 7000 with 96 MiB of RAM, 32 MiB of NAND flash (disk-like) and an RF modulator. Changes were also made on the software side, utilizing Open Embedded for the base Linux operating system. Because the flash memory of this model is not directly executable, the primary boot loader resides in ROM and can recover corrupted secondary boot loader in flash by loading from the serial port | https://en.wikipedia.org/wiki?curid=2819454 | 416,208 |
Glider (aircraft) The Space Shuttle and its Soviet equivalent, the Buran shuttle, were by far the fastest ever aircraft. Recent examples of rocket glider include the privately funded SpaceshipOne which is intended for sub-orbital flight and the XCOR EZ-Rocket which is being used to test engines. Most unpowered rotary-wing aircraft are kites rather than gliders, i.e. they are usually towed behind a car or boat rather than being capable of free flight. These are known as rotor kites. However rotary-winged gliders, 'gyrogliders', were investigated that could descend like an autogyro, using the lift from rotors to reduce the vertical speed. These were evaluated as a method of dropping people or equipment from other aircraft. A paper plane, paper aeroplane (UK), paper airplane (US), paper glider, paper dart or dart is a toy aircraft (usually a glider) made out of paper or paperboard; the practice of constructing paper planes is sometimes referred to as aerogami (Japanese: kamihikōki), after origami, the Japanese art of paper folding. Model glider aircraft are flying or non-flying models of existing or imaginary gliders, often scaled-down versions of full size planes, using lightweight materials such as polystyrene, balsa wood, foam and fibreglass. Designs range from simple glider aircraft, to accurate scale models, some of which can be very large. Larger outdoor models are usually radio-controlled gliders that are piloted remotely from the ground with a transmitter | https://en.wikipedia.org/wiki?curid=13049012 | 264,769 |
Human decontamination Dofficers (Decontamination officers in the "doffing" or disrobing area) are often police or military personnel, ready to handle potentially unruly persons who refuse to cooperate with first responders. For example, the U.S. ARMY SOLDIER AND BIOLOGICAL CHEMICAL COMMAND suggests that: Paul Rega, M.D., FACEP, and Kelly Burkholder-Allen also note, in "The ABCs of Bioterrorism" an additional advantage in decontaminating everyone found at the scene of an incident, because this will help the authorities in searching through everyone's clothes to find suspicious items: Chris Seiple, in "Another Perspective on the Domestic Role of the Military in Consequence Management" suggests that the evidence gathering process of identifying contaminated people and their belongings should also include the process of video surveillance: Although there are the obvious privacy concerns in surveillance, one can also argue that due to the high risk nature of terrorism, such surveillance is warranted, as it is in other high risk areas like bathing complexes where surveillance is often used because of the risk of drowning. In these cases the importance of safety may often be thought to outweigh privacy concerns. One of the elements that separates a drill from a real-life situation is dealing with panicked or uncooperative victims. Security personnel should be assigned to the area for crowd control and to ensure appropriate flow of individuals in and out of the decontamination area | https://en.wikipedia.org/wiki?curid=1004399 | 85,271 |
Rendering (animal products) Rendering is a process that converts waste animal tissue into stable, usable materials. Rendering can refer to any processing of animal products into more useful materials, or, more narrowly, to the rendering of whole animal fatty tissue into purified fats like lard or tallow. Rendering can be carried out on an industrial, farm, or kitchen scale. It can also be applied to non-animal products that are rendered down to pulp. In animal products the majority of tissue processed comes from slaughterhouses, but also includes restaurant grease and butcher shop trimmings and expired meat from grocery stores. This material can include the fatty tissue, bones, and offal, as well as entire carcasses of animals condemned at slaughterhouses and those that have died on farms, in transit, etc. The most common animal sources are beef, pork, mutton, and poultry. The rendering process simultaneously dries the material and separates the fat from the bone and protein. A rendering process yields a fat commodity (yellow grease, choice white grease, bleachable fancy tallow, etc.) and a protein meal (meat and bone meal, poultry byproduct meal, etc.). Rendering plants often also handle other materials, such as slaughterhouse blood, feathers and hair, but do so using processes distinct from true rendering. The occupation of renderer has appeared in "dirtiest jobs" lists | https://en.wikipedia.org/wiki?curid=885462 | 453,715 |
Entomophily or insect pollination is a form of pollination whereby pollen of plants, especially but not only of flowering plants, is distributed by insects. Flowers pollinated by insects typically advertise themselves with bright colours, sometimes with conspicuous patterns (honey guides) leading to rewards of pollen and nectar; they may also have an attractive scent which in some cases mimics insect pheromones. Insect pollinators such as bees have adaptations for their role, such as lapping or sucking mouthparts to take in nectar, and in some species also pollen baskets on their hind legs. This required the coevolution of insects and flowering plants in the development of pollination behaviour by the insects and pollination mechanisms by the flowers, benefiting both groups. The early spermatophytes (seed plants) were largely dependent on the wind to carry their pollen from one plant to another, and it was around 125 to 115 million years ago that a new pollination strategy developed and angiosperms (flowering plants) first appeared. Before that, insect involvement in pollination was limited to "pollination assistants", insects which inadvertently carried the pollen between plants merely by their movements. The real relationship between plants and insects began in the Early Cretaceous, with beetle-pollinated gymnosperms. The morphology of the first fossil basal angiosperms is similar to modern-day plants that are also fertilised by beetles. It seems likely that beetles led the way in insect pollination, followed by flies | https://en.wikipedia.org/wiki?curid=2390680 | 168,969 |
Antikythera mechanism This wreck of a Roman cargo ship was found at a depth of off Point Glyphadia on the Greek island of Antikythera. The team retrieved numerous large artefacts, including bronze and marble statues, pottery, unique glassware, jewellery, coins, and the mechanism. The mechanism was retrieved from the wreckage in 1901, most probably in July of that year. It is not known how the mechanism came to be on the cargo ship, but it has been suggested that it was being taken from Rhodes to Rome, together with other looted treasure, to support a triumphal parade being staged by Julius Caesar. All of the items retrieved from the wreckage were transferred to the National Museum of Archaeology in Athens for storage and analysis. The mechanism appeared at the time to be little more than a lump of corroded bronze and wood; it went unnoticed for two years, while museum staff worked on piecing together more obvious treasures, such as the statues. On 17 May 1902, archaeologist Valerios Stais found that one of the pieces of rock had a gear wheel embedded in it. He initially believed that it was an astronomical clock, but most scholars considered the device to be prochronistic, too complex to have been constructed during the same period as the other pieces that had been discovered. Investigations into the object were dropped until British science historian and Yale University professor Derek J. de Solla Price became interested in it in 1951 | https://en.wikipedia.org/wiki?curid=89732 | 208,697 |
Moti Lal Dhar ( 22 October 1914 – 20 January 2002) was an eminent drug chemist, and science administrator in India. He remained Director Central Drug Research Institute, Lucknow from 1960 until his retirement in 1972 and he has been the only Kashmiri Pandit to serve as Vice- Chancellor, of Banaras Hindu University, B.H.U. | https://en.wikipedia.org/wiki?curid=1275240 | 39,296 |
C15H21N The molecular formula CHN (molar mass: 120.15 g/mol) may refer to: | https://en.wikipedia.org/wiki?curid=24751678 | 75,521 |
Incident Command System All levels of government are required to maintain differing levels of ICS training and private sector organizations regularly use ICS for management of events. ICS is widespread in use from law enforcement to every-day business, as the basic goals of clear communication, accountability, and the efficient use of resources are common to incident and emergency management as well as daily operations. ICS is mandated by law for all Hazardous Materials responses nationally and for many other emergency operations in most states. In practice, virtually all EMS and disaster response agencies utilize ICS, in part after the United States Department of Homeland Security mandated the use of ICS for emergency services throughout the United States as a condition for federal preparedness funding. As part of FEMA's National Response Plan (NRP), the system was expanded and integrated into the National Incident Management System (NIMS). ICS is widely used in the United Kingdom and the United Nations recommended the use of ICS as an international standard. ICS is also used by agencies in Canada. New Zealand has implemented a similar system, known as the Coordinated Incident Management System, Australia has the Australasian Inter-Service Incident Management System and British Columbia, Canada, has BCERMS developed by the Emergency Management BC. In Brazil, ICS is also used by The Fire Department of the State of Rio de Janeiro (CBMERJ) and by the Civil Defense of the State of Rio de Janeiro in every emergency or large-scale events | https://en.wikipedia.org/wiki?curid=1068799 | 461,586 |
C17H12O7 The molecular formula CHO may refer to: | https://en.wikipedia.org/wiki?curid=58090938 | 78,896 |
Transistor count DRAM chips during the early 1970s had three-transistor cells (three transistors per bit), before single-transistor cells (one transistor per bit) became standard since the era of 4Kb DRAM in the mid-1970s. In single-level flash memory, each cell contains one floating-gate MOSFET (one transistor per bit), whereas multi-level flash contains 2, 3 or 4 bits per transistor. Flash memory chips are commonly stacked up in layers, up to 128-layer in production, and 136-layer managed, and available in end-user devices up to 69-layer from manufacturers. Before transistors were invented, relays were used in early computers. The world's first working programmable, fully automatic digital computer, the 1941 Z3 22-bit word length computer, had 2,600 relays, and operated at a clock frequency of about 4–5 Hz. The 1940 Complex Number Computer had fewer than 500 relays, but it was not fully programmable. The second generation of computers were transistor computers that featured boards filled with discrete transistors and magnetic memory cores. The experimental 1953 48-bit Transistor Computer, developed at the University of Manchester, is widely believed to be the first transistor computer to come into operation anywhere in the world (the prototype had 92 point-contact transistors and 550 diodes). A later version the 1955 machine had a total of 250 junction transistors and 1300 point diodes. The Computer also used a small number of tubes in its clock generator, so it was not the first transistorized | https://en.wikipedia.org/wiki?curid=4469365 | 375,133 |
Interstate Highway System There are no I-50 and I-60, as routes with those numbers would likely pass through states that currently have U.S. Highways with the same numbers, which is generally disallowed under highway administration guidelines. Several two-digit numbers are shared between road segments at opposite ends of the country for various reasons. Some such highways are incomplete Interstates (such as I-69 and I-74) and some just happen to share route designations (such as I-76, I-84, I‑86, I-87, and I-88). Some of these were due to a change in the numbering system as a result of a new policy adopted in 1973. Previously, letter-suffixed numbers were used for long spurs off primary routes; for example, western I‑84 was I‑80N, as it went north from I‑80. The new policy stated, "No new divided numbers (such as I-35W and I-35E, etc.) shall be adopted." The new policy also recommended that existing divided numbers be eliminated as quickly as possible; however, an I-35W and I-35E still exist in the Dallas–Fort Worth metroplex in Texas, and an I-35W and I-35E that run through Minneapolis and Saint Paul, Minnesota, still exist. Additionally, due to Congressional requirements, three sections of I-69 in southern Texas will be divided into I-69W, I-69E, and I-69C (for Central). AASHTO policy allows dual numbering to provide continuity between major control points. This is referred to as a concurrency or overlap | https://en.wikipedia.org/wiki?curid=43950 | 304,241 |
Circuit extraction In extraction, it is often helpful to make an (informal) distinction between "designed devices", which are devices that are deliberately created by the designer, and "parasitic devices", which were not explicitly intended by the designer but are inherent in the layout of the circuit. Primarily there are three different parts to the extraction process. These are designed device extraction, interconnect extraction, and parasitic device extraction. These parts are inter-related since various device extractions can change the connectivity of the circuit, e.g., resistors (whether designed or parasitic) convert single nets into multiple electrical nodes. Usually one level of interconnect extraction is used with designed device extraction to provide a circuit for simulation or gate-level reduction, and a second level of interconnect extraction is used with parasitic device extraction to provide a circuit for timing analysis. "Electronic Design Automation For Integrated Circuits Handbook", by Lavagno, Martin and Scheffer, ( ) A survey of the field of electronic design automation. This summary was derived, with permission, from Volume II, Chapter 22, "Layout Extraction", by William Kao, Chi-Yuan Lo, Mark Basel, Raminderpal Singh, Peter Spink, and Lou Scheffer. | https://en.wikipedia.org/wiki?curid=3430375 | 370,997 |
TRIAC (triode for alternating current) is a generic trademark for a three terminal electronic component that conducts current in either direction when triggered. Its formal name is bidirectional triode thyristor or bilateral triode thyristor. A thyristor is analogous to a relay in that a small voltage induced current can control a much larger voltage and current. The illustration on the right shows the circuit symbol for a where "A1" is Anode 1, "A2" is Anode 2, and "G" is Gate. Anode 1 and Anode 2 are normally termed Main Terminal 1 (MT1) and Main Terminal 2 (MT2) respectively. TRIACs are a subset of thyristors and are related to silicon controlled rectifiers (SCRs). TRIACs differ from SCRs in that they allow current flow in both directions, whereas an SCR can only conduct current in a single direction. Most TRIACs can be triggered by applying either a positive or negative voltage to the gate (an SCR requires a positive voltage). Once triggered, SCRs and TRIACs continue to conduct, even if the gate current ceases, until the main current drops below a certain level called the holding current. Gate turn-off thyristors (GTOs) are similar to TRIACs but provide more control by turning off when the gate signal ceases. The bidirectionality of TRIACs makes them convenient switches for alternating-current (AC). In addition, applying a trigger at a controlled phase angle of the AC in the main circuit allows control of the average current flowing into a load (phase control) | https://en.wikipedia.org/wiki?curid=379736 | 376,953 |
Creosote American produced creosote oils typically will have low amounts of anthracene and high amounts of naphthalene, because when forcing the distillate at a temperature that produces anthracene the soft pitch will be ruined and only the hard pitch will remain; this ruins it for use in roofing purposes, and only leaves a product which isn't commercially useful. The use of coal-tar creosote on a commercial scale began in 1838, when a patent covering the use of creosote oil to treat timber was taken out by inventor John Bethell. The "Bethell process"—or as it later became known, the full-cell process—involves placing wood to be treated in a sealed chamber and applying a vacuum to remove air and moisture from wood "cells". The wood is then pressure-treated to impregnate it with creosote or other preservative chemicals, after which vacuum is reapplied to separate the excess treatment chemicals from the timber. Alongside the zinc chloride-based "Burnett process", use of creosoted wood prepared by the Bethell process became a principal way of preserving railway timbers (most notably railway sleepers) to increase the lifespan of the timbers, and avoiding having to regularly replace them. Besides treating wood, it was also used for lighting and fuel. In the beginning, it was only used for lighting needed in harbour and outdoor work, where the smoke that was produced from burning it was of little inconvenience | https://en.wikipedia.org/wiki?curid=69053 | 69,819 |
Bioreactor , "Rate of Mass In – Rate of Mass Out + Rate of Generation = Accumulation" d(Vx)/dt = Fx – Fx + Vr (2) Where r is the rate of cell generation. Dividing both sides of the above equation by V, we obtain dx/dt = (F/V)x – (F/V)x + r (3) In the chemical reaction engineering, F/V is called space velocity(s) and V/F is called the residence time (s). But in biochemical engineering, F/V is known as Dilution rate (D). Accordingly, equation(3) yields: dx/dt = Dx – Dx + r (4) dx/dt = D(x – x) + r (5) For substrate balance, Flow rate of substrate into the bioreactor = FS Flow of the substrate out of the bioreactor = FS Rate of generation of substrate by reaction = –Vr Rate of accumulation of substrate within the reactor = d(VS)/dt Now, apply general mass balance equation i.e., "Rate of Mass In – Rate of Mass Out + Rate of Generation = Accumulation" d(VS)/dt = FS – FS – Vr (6) rearranging above equation, we get dS/dt = D(S –S ) – r (7) where r is the rate of substrate consumption. For the chemical reaction, A ----> P We can write Where, ( –r) = rate of disappearance of A (r) = rate of formation of A k = reaction rate constant C = Concentration of reactant A n = order of reaction with respect to component A For first order reaction, n = 1 and accordingly, –r = k C The reaction kinetics involved in biochemical operations is comparatively difficult to obtain than the chemical reaction kinetics. In biochemical operations, the cell kinetics is used for the unstructured models where balanced growth condition is assumed | https://en.wikipedia.org/wiki?curid=746495 | 150,095 |
Polyethylene terephthalate PET in its natural state is a colorless, semi-crystalline resin. Based on how it is processed, PET can be semi-rigid to rigid, and it is very lightweight. It makes a good gas and fair moisture barrier, as well as a good barrier to alcohol (requires additional "barrier" treatment) and solvents. It is strong and impact-resistant. PET becomes white when exposed to chloroform and also certain other chemicals such as toluene. About 60% crystallization is the upper limit for commercial products, with the exception of polyester fibers. Clear products can be produced by rapidly cooling molten polymer below T glass transition temperature to form an amorphous solid. Like glass, amorphous PET forms when its molecules are not given enough time to arrange themselves in an orderly, crystalline fashion as the melt is cooled. At room temperature the molecules are frozen in place, but, if enough heat energy is put back into them by heating above T, they begin to move again, allowing crystals to nucleate and grow. This procedure is known as solid-state crystallization. When allowed to cool slowly, the molten polymer forms a more crystalline material. This material has spherulites containing many small crystallites when crystallized from an amorphous solid, rather than forming one large single crystal. Light tends to scatter as it crosses the boundaries between crystallites and the amorphous regions between them. This scattering means that crystalline PET is opaque and white in most cases | https://en.wikipedia.org/wiki?curid=292941 | 420,140 |
Poverty Industrial Complex Funds provided by the federal government to help vulerable populations are misused and fuddled towards privat companies and in addition to that used by the states, which often have a tight budget, as a mere revenue stream. The Health and Human Services Department (HHS) is a department that provides poverty assistance. It has an annual budget in the US of around 100 billion. One major branch of the HHS is the Office of Community Service (OCS). The OCS provides funds to states, counties and cities that are intended to lift people out of poverty. The author of "The Poverty Industry: The Exploitation of America’s Most Vulnerable Citizens", Daniel Hatcher, compared the practice of for- profit companies taking over government functions deemed for the most vulnerable in society as a hug "poverty industrial complex" thus comparing it to the military industrial complex. According to Hatcher human service agencies and private companies conspire to create a large poverty industry in which billions in federal aid meant to go towards helping the poorest of society are taken up by these private companies and services provided to those in need, as for example abused children, become inadequate. Among the private companies providing these services are those known for integral roles in our country’s defense industry — like Lockheed Martin and Northrop Grumman. These companies provide services like child support services, Medicaid services, health insurance call centers and welfare-to-work programs | https://en.wikipedia.org/wiki?curid=63243784 | 495,069 |
Canadian Pacific Railway British Columbia, a four-month sea voyage away from the East Coast, had insisted upon a land transport link to the East as a condition for joining Confederation (initially requesting a wagon road). The government however proposed to build a railway linking the Pacific province to the Eastern provinces within 10 years of 20 July 1871. Macdonald saw it as essential to the creation of a unified Canadian nation that would stretch across the continent. Moreover, manufacturing interests in Quebec and Ontario wanted access to raw materials and markets in Western Canada. The first obstacle to its construction was political. The logical route went through the American Midwest and the city of Chicago, Illinois (via some Milwaukee Road and Soo Line Railroad trackage that would later be acquired by CP in the late 20th century). In addition to this was the difficulty of building a railway through the Canadian Rockies; an entirely Canadian route would require crossing of rugged terrain across the barren Canadian Shield and muskeg of Northern Ontario. To ensure this routing, the government offered huge incentives including vast grants of land in the West. In 1873, Sir John A. Macdonald and other high-ranking politicians, bribed in the Pacific Scandal, granted federal contracts to Hugh Allan's Canada Pacific Railway Company (which was unrelated to the current company) rather than to David Lewis Macpherson's Inter-Ocean Railway Company which was thought to have connections to the American Northern Pacific Railway Company | https://en.wikipedia.org/wiki?curid=5959 | 223,364 |
Ray tracing (graphics) A reflection ray is traced in the mirror-reflection direction. The closest object it intersects is what will be seen in the reflection. Refraction rays traveling through transparent material work similarly, with the addition that a refractive ray could be entering or exiting a material. A shadow ray is traced toward each light. If any opaque object is found between the surface and the light, the surface is in shadow and the light does not illuminate it. This recursive ray tracing added more realism to ray traced images. Ray tracing-based rendering's popularity stems from its basis in a realistic simulation of light transport, as compared to other rendering methods, such as rasterization, which focuses more on the realistic simulation of geometry. Effects such as reflections and shadows, which are difficult to simulate using other algorithms, are a natural result of the ray tracing algorithm. The computational independence of each ray makes ray tracing amenable to a basic level of parallelization, but the divergence of ray paths makes high utilization under parallelism quite difficult to achieve in practice. A serious disadvantage of ray tracing is performance (though it can in theory be faster than traditional scanline rendering depending on scene complexity vs. number of pixels on-screen). Until the late 2010s, ray tracing in real time was usually considered impossible on consumer hardware for nontrivial tasks | https://en.wikipedia.org/wiki?curid=26000 | 113,485 |
Software studies Notably related are critical code studies, which is more closely attuned to the code rather than the program, and platform studies, which investigates the relationships between hardware and software. | https://en.wikipedia.org/wiki?curid=17017917 | 112,105 |
Time-sharing In computing, time-sharing is the sharing of a computing resource among many users at the same time by means of multiprogramming and multi-tasking. Its emergence as the prominent model of computing in the 1970s represented a major technological shift in the history of computing. By allowing many users to interact concurrently with a single computer, time-sharing dramatically lowered the cost of providing computing capability, made it possible for individuals and organizations to use a computer without owning one, and promoted the interactive use of computers and the development of new interactive applications. The earliest computers were extremely expensive devices, and very slow in comparison to later models. Machines were typically dedicated to a particular set of tasks and operated by control panels, the operator manually entering small programs via switches in order to load and run a series of programs. These programs might take hours, or even weeks, to run. As computers grew in speed, run times dropped, and soon the time taken to start up the next program became a concern. Batch processing methodologies evolved to decrease these "dead periods" by queuing up programs so that as soon as one program completed, the next would start. To support a batch processing operation, a number of comparatively inexpensive card punch or paper tape writers were used by programmers to write their programs "offline" | https://en.wikipedia.org/wiki?curid=30958 | 381,679 |
BITNET was a co-operative U.S. university computer network founded in 1981 by Ira Fuchs at the City University of New York (CUNY) and Greydon Freeman at Yale University. The first network link was between CUNY and Yale. The name originally meant "Because It's There Network", but it eventually came to mean "Because It's Time Network". A college or university wishing to join was required to lease a data circuit (phone line) from a site to an existing node, buy modems for each end of the data circuit, sending one to the connecting point site, and allow other institutions to connect to its site free of charge. Bitnet's NJE (Network Job Entry) network protocols, called RSCS, were used for the huge IBM internal network known as VNET. links originally ran at 9600 baud. The protocols were eventually ported to non-IBM mainframe operating systems, and became particularly widely implemented under VAX/VMS, in addition to DECnet. featured email and LISTSERV software, but predated the World Wide Web, the common use of FTP, and Gopher. Gateways for the lists made them available on Usenet. also supported interactive transmission of files and messages to other users. A gateway service called TRICKLE enabled users to request files from Internet FTP servers in 64 Kb UUencoded chunks. The "Interchat Relay Network", popularly known as Bitnet Relay, was the network's instant messaging feature. differed from the Internet in that it was a point-to-point "store and forward" network | https://en.wikipedia.org/wiki?curid=18950033 | 256,970 |
Water wheel The water mill was used for grinding grain, producing flour for bread, malt for beer, or coarse meal for porridge. Hammermills used the wheel to operate hammers. One type was fulling mill, which was used for cloth making. The trip hammer was also used for making wrought iron and for working iron into useful shapes, an activity that was otherwise labour-intensive. The water wheel was also used in papermaking, beating material to a pulp. In the 13th century water mills used for hammering throughout Europe improved the productivity of early steel manufacturing. Along with the mastery of gunpowder, waterpower provided European countries worldwide military leadership from the 15th century. Millwrights distinguished between the two forces, impulse and weight, at work in water wheels long before 18th-century Europe. Fitzherbert, a 16th-century agricultural writer, wrote "druieth the wheel as well as with the weight of the water as with strengthe [impulse]". Leonardo da Vinci also discussed water power, noting "the blow [of the water] is not weight, but excites a power of weight, almost equal to its own power". However, even realisation of the two forces, weight and impulse, confusion remained over the advantages and disadvantages of the two, and there was no clear understanding of the superior efficiency of weight. Prior to 1750 it was unsure as to which force was dominant and was widely understood that both forces were operating with equal inspiration amongst one another | https://en.wikipedia.org/wiki?curid=150248 | 365,660 |
Markstein number In combustion engineering and explosion studies, the characterizes the effect of local heat release of a propagating flame on variations in the surface topology along the flame and the associated local flame front curvature. The dimensionless is defined as: where formula_2 is the Markstein length, and formula_3 is the characteristic laminar flame thickness. The larger the Markstein length, the greater the effect of curvature on localised burning velocity. It is named after George H. Markstein (1911—2011), who showed that thermal diffusion stabilized the curved flame front and proposed a relation between the critical wavelength for stability of the flame front, called the Markstein length, and the thermal thickness of the flame. Phenomenological Markstein numbers with respect to the combustion products are obtained by means of the comparison between the measurements of the flame radii as a function of time and the results of the analytical integration of the linear relation between the flame speed and either flame stretch rate or flame curvature. The burning velocity is obtained at zero stretch, and the effect of the flame stretch acting upon it is expressed by a Markstein length. Because both flame curvature and aerodynamic strain contribute to the flame stretch rate, there is a associated with each of these components. The with respect to the unburnt gas mixture for a one step reaction in the limit of large activation energy asymptotics was derived by Paul Clavin and Forman A. Williams in 1982 | https://en.wikipedia.org/wiki?curid=25872275 | 448,782 |
Plug-in electric vehicles in Norway Among the top selling countries of all-electric cars in 2012, Norway ranked 5th with a 7% market share of global EV sales. Sales in 2012 were led by the Nissan Leaf with 2,487 units registered, including 189 imported used Leafs, and Leaf sales represented 53% of the plug-in segment sales that year. Cumulative sales reached 2,860 Leafs since its launch in September 2011, accounting for more than 5% of the Leaf's global sales. Norway was the first country in the world where an electric car ranked among the top 10 best selling cars, as the Nissan Leaf ranked 9th in October new car sales, and ended 2012 in the 13th place, representing a market share of 1.7% of all new car sales in the country, up from 0.3% in 2011. The other top selling models in 2012 were the Mitsubishi i-MiEV with 672 units (7 used imports), Citroën C-Zero 560 (47 used imports), and Peugeot iOn 477 (47 used imports), for a total of 1,709 i MiEV family cars registered. Since 2009, the i-MiEV family sold 3,147 new electric cars through December 2012. Plug-in electric car registrations totaled 10,769 units in 2013, of which used imports represented 20%. Total registrations included 387 plug-in hybrids and 355 all-electric light commercial vans, together representing 6.9% of total 2013 registrations, and reflecting the continued dominance of pure electric vehicles in the Norwegian market. The plug-in electric segment in Norway grew 129% from 2012 to 2013, achieving the second highest growth rate in the world after the Netherlands (338%) | https://en.wikipedia.org/wiki?curid=37528172 | 392,313 |
Super Bowl I Justin Peters of "Slate" watched all the Super Bowls over a two-month period in 2015 before Super Bowl 50. He mentioned the first Super Bowl's having "two dudes in rocket packs who flew around the stadium. I can forgive a lot of bad football as long as the game features two dudes in honest-to-God rocket packs." The temperature was mild with clear skies. This game is the only Super Bowl to have been broadcast in the United States by two television networks simultaneously (no other NFL game was subsequently carried nationally on more than one network until December 29, 2007, when the New England Patriots faced the New York Giants on NBC, CBS, and the NFL Network). At the time, NBC held the rights to nationally televise AFL games while CBS had the rights to broadcast NFL games. Both networks were allowed to cover the game. During the week, tensions flared between the staffs of the two networks (longtime arch-rivals in American broadcasting), who each wanted to win the ratings war, to the point where a fence was built between the CBS and NBC trucks. Each network used its own announcers: Ray Scott (doing play-by-play for the first half), Jack Whitaker (doing play-by-play for the second half) and Frank Gifford provided commentary on CBS, while Curt Gowdy and Paul Christman were on NBC. While Rozelle allowed NBC to telecast the game, he decreed it would not be able to use its cameramen and technical personnel, instead forcing it to use the feed provided by CBS, since the Coliseum was home to the NFL's Rams | https://en.wikipedia.org/wiki?curid=29128 | 419,766 |
History of the transistor Pierce, was the clear winner of an internal ballot (owing in part to the affinity that Bell engineers had developed for the suffix "-istor"). The rationale for the name is described in the following extract from the company's Technical Memorandum calling for votes: Pierce recalled the naming somewhat differently: The Nobel Foundation states that the term is a combination of the words "transfer" and "resistor". Shockley was upset about the device being credited to Brattain and Bardeen, who he felt had built it "behind his back" to take the glory. Matters became worse when Bell Labs lawyers found that some of Shockley's own writings on the transistor were close enough to those of an earlier 1925 patent by Julius Edgar Lilienfeld that they thought it best that his name be left off the patent application. Shockley was incensed, and decided to demonstrate who was the real brains of the operation. Only a few months later he invented an entirely new type of transistor with a layer or "sandwich" structure. This new form was considerably more robust than the fragile point-contact system, and would go on to be used for the vast majority of all transistors into the 1960s. It would evolve into the bipolar junction transistor. The static induction transistor, the first high frequency transistor concept, was invented by Japanese engineers Jun-ichi Nishizawa and Y. Watanabe in 1950, and was finally able to produce some experimental prototypes in 1975 | https://en.wikipedia.org/wiki?curid=12289129 | 403,455 |
Pevsner Architectural Guides The original intention was to maintain whatever boundaries were current at the time of writing; in the first years of the survey these were the traditional counties of England. However, boundary changes to the London area in 1965 and the rest of England in 1974 meant that this was no longer practicable. As such there are now many variants: "Cumbria", for example, covers the modern non-metropolitan countyexcepting the district of Sedbergh which although in modern Cumbria is included in the volume covering the West Riding of Yorkshire. Conversely, the Furness areageographically in Cumbria but traditionally in Lancashireis included, having been omitted from the predecessor volume, "Cumberland and Westmorland". The six volumes currently covering London collectively represent the 32 London boroughs plus the City, which constitute the modern Greater London region, rather than earlier divisions. The entire volume on Middlesex was an early casualty of this rearrangement, as are parts of the revised volumes covering Surrey, Essex and Kent. The forthcoming "Birmingham and the Black Country" volume covers the area bounded by the modern West Midlands metropolitan county, but minus the Metropolitan Borough of Coventry and the rural part of Metropolitan Borough of Solihull. These appear in the revised "Warwickshire" volume, despite no longer being in that county. Hence "Warwickshire" now follows the boundary of neither the traditional nor the modern county | https://en.wikipedia.org/wiki?curid=17749016 | 298,333 |
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