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https://en.wikipedia.org/wiki/Homologous%20temperature | Homologous temperature expresses the thermodynamic temperature of a material as a fraction of the thermodynamic temperature of its melting point (i.e. using the Kelvin scale):
For example, the homologous temperature of lead at room temperature (25 °C) is approximately 0.50 (TH = T/Tmp = 298 K/601 K = 0.50).
Significance of the homologous temperature
The homologous temperature of a substance is useful for determining the rate of steady state creep (diffusion dependent deformation). A higher homologous temperature results in an exponentially higher rate of diffusion dependent deformation.
Additionally, for a given fixed homologous temperature, two materials with different melting points would have similar diffusion-dependent deformation behaviour. For example, solder (Tmp = 456 K) at 115 °C would have comparable mechanical properties to copper (Tmp = 1358 K) at 881 °C, because they would both be at 0.85Tmp despite being at different absolute temperatures.
In electronics applications, where circuits typically operate over a −55 °C to +125 °C range, eutectic tin-lead (Sn63) solder is working at 0.48Tmp to 0.87Tmp. The upper temperature is high relative to the melting point; from this we can deduce that solder will have limited mechanical strength (as a bulk material) and significant creep under stress. This is borne out by its comparatively low values for tensile strength, shear strength and modulus of elasticity. Copper, on the other hand, has a much higher melting point, so foils are working at only 0.16Tmp to 0.29Tmp and their properties are little affected by temperature. |
https://en.wikipedia.org/wiki/Platinosis | Platinosis is an allergy-like reaction to exposure to soluble salts of platinum.
The symptoms of platinosis may include asthma, dermatitis, dyspnea, conjunctival vasodilatation, and rhinopharyngitis.
The symptoms are progressive, sometimes taking months to years to appear. Platinosis is usually associated with workers in industries related to platinum production.
The effects are permanent.
Halogeno-platinum compounds are among the most potent respiratory and skin sensitisers known, therefore it is vital that exposure via the skin and by breathing contaminated air is carefully controlled.
In practice, the compounds mainly responsible for platinum sensitisation are typically the soluble, ionic, platinum-chloro compounds such as ammonium hexachloroplatinate and tetrachloroplatinate, and hexachloroplatinic acid. Other ionic halogeno compounds are also sensitisers, the order of allergenicity being Cl > Br > I.
Neutral compounds such as cis-platin and ammine and nitro complexes such as [Pt(NH3)4]Cl2, K2[Pt(NO2)4] and platinum nitrate are not considered to be allergenic; neither is the metal.
See also
Heavy metal poisoning |
https://en.wikipedia.org/wiki/Ehrenfest%20theorem | The Ehrenfest theorem, named after Austrian theoretical physicist Paul Ehrenfest, relates the time derivative of the expectation values of the position and momentum operators x and p to the expectation value of the force on a massive particle moving in a scalar potential ,
The Ehrenfest theorem is a special case of a more general relation between the expectation of any quantum mechanical operator and the expectation of the commutator of that operator with the Hamiltonian of the system
where is some quantum mechanical operator and is its expectation value.
It is most apparent in the Heisenberg picture of quantum mechanics, where it amounts to just the expectation value of the Heisenberg equation of motion. It provides mathematical support to the correspondence principle.
The reason is that Ehrenfest's theorem is closely related to Liouville's theorem of Hamiltonian mechanics, which involves the Poisson bracket instead of a commutator. Dirac's rule of thumb suggests that statements in quantum mechanics which contain a commutator correspond to statements in classical mechanics where the commutator is supplanted by a Poisson bracket multiplied by . This makes the operator expectation values obey corresponding classical equations of motion, provided the Hamiltonian is at most quadratic in the coordinates and momenta. Otherwise, the evolution equations still may hold approximately, provided fluctuations are small.
Relation to classical physics
Although, at first glance, it might appear that the Ehrenfest theorem is saying that the quantum mechanical expectation values obey Newton’s classical equations of motion, this is not actually the case. If the pair were to satisfy Newton's second law, the right-hand side of the second equation would have to be
which is typically not the same as
If for example, the potential is cubic, (i.e. proportional to ), then is quadratic (proportional to ). This means, in the case of Newton's second law, the right side would |
https://en.wikipedia.org/wiki/ZEBRA%20%28computer%29 | The ZEBRA (Zeer Eenvoudige Binaire Reken Automaat translated Very Simple Binary Automatic Calculator) was one of the first computers to be designed in the Netherlands, (the first one was the "ARRA") and one of the first Dutch computers to be commercially available. It was designed by Willem van der Poel of the Netherlands Post, Telegraph and Telephone, and first delivered in 1958. The production run consisted of fifty-five machines, manufactured and marketed by the British company Standard Telephones and Cables, Ltd.
The ZEBRA was a binary, two-address machine with a 33-bit word length. Storage was provided by a magnetic drum memory holding 8K words organised as 256 tracks of 32 instructions; accumulators were also implemented as recirculating drum tracks in a manner similar to that used in the Bendix G-15. Peripherals included paper tape reader and punch, and a teleprinter.
In 1967, six Zebra computers were in use in UK universities and technical colleges.
Programming
Large parts of the code and operating systems for ZEBRA were written by deafblind mathematician Gerrit van der Mey.
In contrast to most processors, the ZEBRA didn't have different types of instructions. Instead, the operation of an instruction was controlled by fifteen bits in the operation field. Also, it didn't have a program counter in the traditional sense.
The ZEBRA instruction word is 33 bits, consisting of a 13-bit drum address, referencing one of the 256 tracks of 32 entries on the memory drum, a five-bit register (or I/O) address, and the 15-bit operation field.
Each bit of the operation field had a distinct meaning and could be used in nearly any combination, leading to many elegant tricks that today might be considered the domain of microprogramming. The operation bits determined things as the sign of the data to be used; if the accumulator was cleared (changing an addition into a load), if a rotation was to be applied, and so on. Also, there was an operation bits that determined if |
https://en.wikipedia.org/wiki/International%20Conference%20on%20Software%20Engineering | The International Conference on Software Engineering (ICSE), is one of the largest annual software engineering conferences. It has an 'A*' rating in the Rankings of the Computing Research and Education Association of Australasia (CORE) and an 'A1' rating from the Brazilian ministry of education. Furthermore, it is the software engineering conference with the highest Microsoft Academic field rating. The first ICSE conference was in 1975 in Washington DC.
List of Conferences
Past and future ICSE conferences include: |
https://en.wikipedia.org/wiki/Rosenstiel%20Award | The Lewis S. Rosenstiel Award for Distinguished Work in Basic Medical Research is awarded by Brandeis University. It was established in 1971 "as an expression of the conviction that educational institutions have an important role to play in the encouragement and development of basic science as it applies to medicine".
Medals are presented annually at Brandeis University on the basis of recommendations of a panel of scientists selected by the Rosenstiel Basic Medical Sciences Research Center. Awards are given to scientists for recent discoveries of "particular originality" and "importance to basic medical research". A $30,000 prize and a medallion accompanies each award.
The Rosenstiel Basic Medical Sciences Research Center, named after Lewis Solon Rosenstiel, was established in 1968, carrying out research in basic medical science.
Recipients
Source: Brandeis University
2022 Christine Holt and Erin Schuman, for their pioneering work that shed light on the role of local protein synthesis in neuronal development and function.
2021 Robert H. Singer, for his key role in revealing the dynamics of gene expression using high-resolution imaging.
2020 Katalin Karikó and Drew Weissman, for their pioneering work in the modification of nucleic acids to develop RNA therapeutics and vaccines.
2019 David Julius and Ardem Patapoutian, for their remarkable contributions to our understanding of the sensations of temperature, pain and touch.
2018 Stephen C. Harrison, for his fundamental and far-reaching studies of protein structure using X-ray crystallography
2017 Titia de Lange, for her elucidation of the protection of telomeres and the maintenance of genome stability
2016 Susan Lindquist (posthum), in recognition of her pioneering work on the mechanisms of protein folding and the severe consequences of protein misfolding that are manifest in disease
2015 Yoshinori Ohsumi, in recognition of his pioneering discoveries of molecular pathways and biological functions of protein deg |
https://en.wikipedia.org/wiki/Fluid%20theory%20of%20electricity | Fluid theories of electricity are outdated theories that postulated one or more electrical fluids which were thought to be responsible for many electrical phenomena in the history of electromagnetism. The "two-fluid" theory of electricity, created by Charles François de Cisternay du Fay, postulated that electricity was the interaction between two electrical 'fluids.' An alternate simpler theory was proposed by Benjamin Franklin, called the unitary, or one-fluid, theory of electricity. This theory claimed that electricity was really one fluid, which could be present in excess, or absent from a body, thus explaining its electrical charge. Franklin's theory explained how charges could be dispelled (such as those in Leyden jars) and how they could be passed through a chain of people. The fluid theories of electricity eventually became updated to include the effects of magnetism, and electrons (upon their discovery).
Fluid theories
In the 1700s many physical phenomena were thought of in terms of an aether, which was a fluid that could permeate matter. This idea had been used for centuries, and was the basis of thinking about physical phenomena, such as electricity, as liquids. Other 18th century examples of fluid models are Lavoisier's caloric and the magnetic fluids of Coulomb and Aepinus.
Two-fluid theory
By the 18th century, one of a few theories explaining observed electrical phenomena was the two-fluid theory. This theory is generally attributed to Charles François de Cisternay du Fay. du Fay's theory suggested that electricity was composed of two liquids, which could flow through solid bodies. One liquid carried a positive charge, and the other a negative charge. When these two liquids came into contact with one another, they would produce a neutral charge. This theory dealt mainly with explaining electrical attraction and repulsion, rather than how an object could be charged or discharged.
du Fay observed this while repeating an experiment created by Otto von G |
https://en.wikipedia.org/wiki/Web%20fiction | Web fiction is written works of literature available primarily or solely on the Internet. A common type of web fiction is the web serial. The term comes from old serial stories that were once published regularly in newspapers and magazines.
Unlike most modern books, a work of web fiction is often not published as a whole. Instead, it is released on the Internet in installments or chapters as they are finished, although published compilations and anthologies are not unknown. The web serial form dominates in the category of fan fiction, as writing a serial takes less specialized software and often less time than an ebook.
Web-based fiction dates to the earliest days of the World Wide Web, including the extremely popular The Spot (1995–1997), a tale told through characters' journal entries and interactivity with its audience. The Spot spawned many similar sites, including Ferndale and East Village, though these were not as successful and did not last long. Most of these early ventures are no longer in existence.
Since 2008, web fiction has proliferated in popularity. Possibly as a result of this, more fans of web serials have decided to create their own, propagating the form further, leading to the number of serious, original works growing quickly. Some serials utilize the formats of the media to include things not possible in ordinary books, such as clickable maps, pop-up character bios, sorting posts by tag, and video.
Web fiction has become hugely popular in China, with revenues topping US$2.5 billion.
Publication formats
Some of the most popular platforms for publishing web serials and webcomics include Archive of our Own (AO3), Wattpad, Fanfiction.net, Webtoon, Tapas, LiveJournal, and Radish. With their large user bases, the popularity of these sites may arise from their interactive aspects allowing creators, readers, and other users to communicate with one another and create new communities.
Another format in use is the internet forum. A free forum service |
https://en.wikipedia.org/wiki/Interactive%20Connectivity%20Establishment | Interactive Connectivity Establishment (ICE) is a technique used in computer networking to find ways for two computers to talk to each other as directly as possible in peer-to-peer networking. This is most commonly used for interactive media such as Voice over Internet Protocol (VoIP), peer-to-peer communications, video, and instant messaging. In such applications, communicating through a central server would be slow and expensive, but direct communication between client applications on the Internet is very tricky due to network address translators (NATs), firewalls, and other network barriers.
ICE is developed by the Internet Engineering Task Force MMUSIC working group and is published as RFC 8445, as of August 2018, and has obsolesced both RFC 5245 and RFC 4091.
Overview
Network address translation (NAT) became an effective technique in delaying the exhaustion of the available address pool of Internet Protocol version 4, which is inherently limited to around four billion unique addresses. NAT gateways track outbound requests from a private network and maintain the state of each established connection to later direct responses from the peer on the public network to the peer in the private network, which would otherwise not be directly addressable.
VoIP, peer-to-peer, and many other applications require address information of communicating peers within the data streams of the connection, rather than only in the Internet Protocol packet headers. For example, the Session Initiation Protocol (SIP) communicates the IP address of network clients for registration with a location service, so that telephone calls may be routed to registered clients. ICE provides a framework with which a communicating peer may discover and communicate its public IP address so that it can be reached by other peers.
Session Traversal Utilities for NAT (STUN) is a standardized protocol for such address discovery including NAT classification. Traversal Using Relays around NAT (TURN) places |
https://en.wikipedia.org/wiki/Super%20City%20%28toy%29 | The Super City toy is a construction set produced by Ideal Toys in 1967. It is similar to Lego, small plastic pieces which are assembled to create complex structures. However Super City is more oriented to buildings and allows more sophisticated constructions. Children could build skyscrapers, research laboratories and pharmaceutical factories.
Super City is made of plastic frames which connect at the edges with grooves and studs into which fit a variety of wall panels. Frames can be connected at right angles by grooved and flanged columns. Frames are primarily square with some rectangles (half squares) and triangles (diagonally halved rectangles). The inserts are mostly wall finishes in either thin textured and coloured opaque plastic or windows in coloured (and sometimes textured) transparent plastic. There are a few card inserts, generally with printed signs. In addition there are a variety of special inserts and frames including shop windows, bow window, house door with pillars, clock, flag pole, garage door and revolving doors. There are also balconies and canopies. Other cardboard parts include helicopter pads and "building extenders". Roofs are generally intended to be flat (some of the plastic inserts are domed or pyramidal roof lights and panels) but card roofs are supplied for more domestic buildings.
However Super City proved too complicated for young children, and it was almost impossible for small fingers to work with. It was progressively removed from market from 1968.
Douglas Coupland said about Super City: "anything made from Super City looked like a Craig Ellwood, or a Neutra or a Wallace K. Harrison". He also stated that Super City was "the best building kit ever made, possibly even better than Lego".
External links
Jackie Britton about Super City
Douglas Coupland's exhibition, 'Super City', at the Canadian Centre for Architecture in Montreal
SuperCity Manual on Flickr
Construction toys |
https://en.wikipedia.org/wiki/Nintendo%20Wi-Fi%20Connection | Nintendo Wi-Fi Connection (WFC) is a discontinued online multiplayer gaming service run by Nintendo to provide free online play in compatible Nintendo DS and Wii games. The service included the company's Wii Shop Channel and DSi Shop game download services. It also ran features for the Wii and Nintendo DS systems.
Games designed to take advantage of Nintendo Wi-Fi Connection offered Internet play integrated into the game. When promoting this service, Nintendo emphasized the simplicity and speed of starting an online game. For example, in Mario Kart DS, an online game was initiated by selecting the online multiplayer option from the main menu, then choosing whether to play with friends, or to play with other players (either in the local region or worldwide) at about the same skill level. After a selection was made, the game started searching for an available player.
On January 26, 2012, Nintendo Wi-Fi Connection service was succeeded by and absorbed into Nintendo Network. This new online system unified the 3DS and Wii U platforms and replaced Friend Codes, while providing paid downloadable content, an online community style multiplayer system, and personal accounts. Nintendo Network is fully supported on the Nintendo 3DS and on the Wii U, whilst still continuing providing partial legacy support for both Wii and Nintendo DS under the Nintendo Wi-Fi Connection brand. Specifically, the Wii U can boot to Wii mode and then access the Wii Message Board messages which have been recorded by the gameplay progress of compatible local games, but it cannot send Wii Message Board messages remotely between different machines.
On May 20, 2014, at 7:30 PM PT, Nintendo ended the Nintendo Wi-Fi Connection service (WFC) for all games, except for Nintendo Wi-Fi Connection pay and play branded games, Nintendo DSi Shop services (which were terminated on March 31, 2017), and Nintendo Wii Shop Channel services (ended on January 30, 2019).
After the end of the service, there have been v |
https://en.wikipedia.org/wiki/Tannaka%E2%80%93Krein%20duality | In mathematics, Tannaka–Krein duality theory concerns the interaction of a compact topological group and its category of linear representations. It is a natural extension of Pontryagin duality, between compact and discrete commutative topological groups, to groups that are compact but noncommutative. The theory is named after Tadao Tannaka and Mark Grigorievich Krein. In contrast to the case of commutative groups considered by Lev Pontryagin, the notion dual to a noncommutative compact group is not a group, but a category of representations Π(G) with some additional structure, formed by the finite-dimensional representations of G.
Duality theorems of Tannaka and Krein describe the converse passage from the category Π(G) back to the group G, allowing one to recover the group from its category of representations. Moreover, they in effect completely characterize all categories that can arise from a group in this fashion. Alexander Grothendieck later showed that by a similar process, Tannaka duality can be extended to the case of algebraic groups via Tannakian formalism. Meanwhile, the original theory of Tannaka and Krein continued to be developed and refined by mathematical physicists. A generalization of Tannaka–Krein theory provides the natural framework for studying representations of quantum groups, and is currently being extended to quantum supergroups, quantum groupoids and their dual Hopf algebroids.
The idea of Tannaka–Krein duality: category of representations of a group
In Pontryagin duality theory for locally compact commutative groups, the dual object to a group G is its character group which consists of its one-dimensional unitary representations. If we allow the group G to be noncommutative, the most direct analogue of the character group is the set of equivalence classes of irreducible unitary representations of G. The analogue of the product of characters is the tensor product of representations. However, irreducible representations of G in general |
https://en.wikipedia.org/wiki/Roleplay%20simulation | Roleplay simulation is an experiential learning method in which either amateur or professional roleplayers (also called interactors) improvise with learners as part of a simulated scenario. Roleplay is designed primarily to build first-person experience in a safe and supportive environment. Roleplay is widely acknowledged as a powerful technique across multiple avenues of training and education.
History
Howard Barrows invented the model for medical patient role-playing in 1963 at University of Southern California. This program allowed doctors practice taking medical histories and conducting physical examinations by participating in a one-on-one scenario with a role-player. The role-players (called Standardized Patients or SP) were also trained on providing performance evaluations after the fiction of the scenario was complete. Barrows continued to evolve this model, eventually bringing it to other physicians in the 1970s, and into the academic world in the 1980s. Today, many hospitals and medical universities have their own standardized patient programs that employ part-time role-players trained to specific standards of interaction. The Association of Standardized Patient Educators has members from six different continents.
An industry of professional skills training emerged in the late 1990s, primarily in the United Kingdom. Companies began hiring acting professionals to create situational dramas to be overcome by learners as part of an experiential learning methodology. Today, there are more than twenty companies in the UK that specialize in providing role-players for workplace simulations.
Professional military role-players have been employed by the US Military since 2001, primarily as a response to the September 11, 2001 attacks in the United States. Preparation requirements for the resulting War in Afghanistan created a need for cultural role-players skilled in languages and customs of current theaters of war to populate simulated villages and urban enviro |
https://en.wikipedia.org/wiki/NAND%20gate | In digital electronics, a NAND gate (NOT-AND) is a logic gate which produces an output which is false only if all its inputs are true; thus its output is complement to that of an AND gate. A LOW (0) output results only if all the inputs to the gate are HIGH (1); if any input is LOW (0), a HIGH (1) output results. A NAND gate is made using transistors and junction diodes. By De Morgan's laws, a two-input NAND gate's logic may be expressed as =+, making a NAND gate equivalent to inverters followed by an OR gate.
The NAND gate is significant because any boolean function can be implemented by using a combination of NAND gates. This property is called functional completeness. It shares this property with the NOR gate. Digital systems employing certain logic circuits take advantage of NAND's functional completeness.
NAND gates with two or more inputs are available as integrated circuits in transistor-transistor logic, CMOS, and other logic families.
Logic
The function is logically equivalent to
One way of expressing A NAND B is , where the symbol signifies AND and the bar signifies the negation of the expression under it: in essence, simply .
Symbols
There are three symbols for NAND gates: the MIL/ANSI symbol, the IEC symbol and the deprecated DIN symbol sometimes found on old schematics. For more information see logic gate symbols. The ANSI symbol for the NAND gate is a standard AND gate with an inversion bubble connected.
Hardware design and pinout
NAND gates are basic logic gates, and as such they are recognised in TTL and CMOS ICs.
The standard, 4000 series, CMOS IC is the 4011, which includes four independent, two-input, NAND gates. These devices are available from many semiconductor manufacturers. These are usually available in both through-hole DIL and SOIC format. Datasheets are readily available in most datasheet databases.
The standard 2-, 3-, 4- and 8-input NAND gates are available:
CMOS
4011: Quad 2-input NAND gate
4023: Triple 3-input NAN |
https://en.wikipedia.org/wiki/Fluorescence%20correlation%20spectroscopy | Fluorescence correlation spectroscopy (FCS) is a statistical analysis, via time correlation, of stationary fluctuations of the fluorescence intensity. Its theoretical underpinning originated from L. Onsager's regression hypothesis. The analysis provides kinetic parameters of the physical processes underlying the fluctuations. One of the interesting applications of this is an analysis of the concentration fluctuations of fluorescent particles (molecules) in solution. In this application, the fluorescence emitted from a very tiny space in solution containing a small number of fluorescent particles (molecules) is observed. The fluorescence intensity is fluctuating due to Brownian motion of the particles. In other words, the number of the particles in the sub-space defined by the optical system is randomly changing around the average number. The analysis gives the average number of fluorescent particles and average diffusion time, when the particle is passing through the space. Eventually, both the concentration and size of the particle (molecule) are determined. Both parameters are important in biochemical research, biophysics, and chemistry.
FCS is such a sensitive analytical tool because it observes a small number of molecules (nanomolar to picomolar concentrations) in a small volume (~1μm3). In contrast to other methods (such as HPLC analysis) FCS has no physical separation process; instead, it achieves its spatial resolution through its optics. Furthermore, FCS enables observation of fluorescence-tagged molecules in the biochemical pathway in intact living cells. This opens a new area, "in situ or in vivo biochemistry": tracing the biochemical pathway in intact cells and organs.
Commonly, FCS is employed in the context of optical microscopy, in particular Confocal microscopy or two-photon excitation microscopy. In these techniques light is focused on a sample and the measured fluorescence intensity fluctuations (due to diffusion, physical or chemical reactions, |
https://en.wikipedia.org/wiki/List%20scheduling | List scheduling is a greedy algorithm for Identical-machines scheduling. The input to this algorithm is a list of jobs that should be executed on a set of m machines. The list is ordered in a fixed order, which can be determined e.g. by the priority of executing the jobs, or by their order of arrival. The algorithm repeatedly executes the following steps until a valid schedule is obtained:
Take the first job in the list (the one with the highest priority).
Find a machine that is available for executing this job.
If a machine is found, schedule this job on that machine.
Otherwise (no suitable machine is available), select the next job in the list.
Example
Suppose there are five jobs with processing-times {4,5,6,7,8}, and m=2 processors. Then, the resulting schedule is {4,6,8}, {5,7}, and the makespan is max(18,12)=18; if m=3, then the resulting schedule is {4,7}, {5,8}, {6}, and the makespan is max(11,13,6)=13.
Performance guarantee
The algorithm runs in time , where n is the number of jobs. The algorithm always returns a partition of the jobs whose makespan is at most times the optimal makespan. This is due to the fact that both the length of the longest job and the average length of all jobs are lower bounds for the optimal makespan. The algorithm can be used as an online algorithm, when the order in which the items arrive cannot be controlled.
Ordering strategies
Instead of using an arbitrary order, one can pre-order the jobs in order to attain better guarantees. Some known list scheduling strategies are:
Highest level first algorithm, or HLF;
Longest path algorithm or LP;
Longest-processing-time-first scheduling, or LPT; this variant decreases the approximation ratio to .
Critical path method.
Heterogeneous Earliest Finish Time or HEFT. For the case heterogeneous workers.
Anomalies
The list scheduling algorithm has several anomalies. Suppose there are m=3 machines, and the job lengths are: 3, 2, 2, 2, 4, 4, 4, 4, 9Further, suppose that all the " |
https://en.wikipedia.org/wiki/Salad%20cream | Salad cream is a creamy, pale yellow condiment based on an emulsion of about 25–50 percent oil in water, emulsified by egg yolk and acidulated by spirit vinegar. It is somewhat similar in composition to mayonnaise and may include other ingredients such as sugar, mustard, salt, thickener, spices, flavouring and colouring. The first ready-made commercial product was introduced in the United Kingdom in 1914, where it is used as a salad dressing and a sandwich spread.
Historically, salad cream, often mentioned in Victorian sources, consisted of "hard-boiled eggs puréed with cream, mustard, salt and vinegar".
Brands
In the UK, it has been produced by companies including H. J. Heinz Company and Crosse & Blackwell. Heinz Salad Cream was the first brand developed exclusively for the UK market. When first created in the Harlesden kitchens of Heinz in 1914, it was prepared by hand. The jars were packed in straw-lined barrels with 12 dozen in each. The quota was 180 dozen jars a day, with a halfpenny a dozen bonus if the workforce could beat the target.
See also
List of sauces
Miracle Whip, a similar North American condiment |
https://en.wikipedia.org/wiki/Treadwheel | A treadwheel, or treadmill, is a form of engine typically powered by humans. It may resemble a water wheel in appearance, and can be worked either by a human treading paddles set into its circumference (treadmill), or by a human or animal standing inside it (treadwheel). These devices are no longer used for power or punishment, and the term "treadmill" has come to mean an exercise machine for running, walking or other exercises in place.
History
Uses of treadwheels included raising water, to power cranes, or grind grain. They were used extensively in the Greek and Roman world, such as in the reverse overshot water-wheel used for dewatering purposes. They were widely used in the Middle ages to lift the stones in the construction of Gothic cathedrals. There is a literary reference to one in 1225, and one treadwheel crane survives at Chesterfield, Derbyshire and is housed in the Museum. It has been dated to the early 14th century and was housed in the top of the church tower until its removal in 1947. They were used extensively in the Renaissance famously by Brunelleschi during the construction of Florence cathedral.
Penal treadmills were used in prisons during the early Victorian period in the UK as a form of punishment. According to The Times in 1827, and reprinted in William Hone's Table-Book in 1838, the amount prisoners walked per day on average varied, from the equivalent of 6,600 vertical feet at Lewes to as much as 17,000 vertical feet in ten hours during the summertime at Warwick gaol. In 1902, the British government banned the use of the treadwheel as a form of punishment.
See also
Chain pump
The Experiment, a horse-powered boat
Horse mill
List of historical harbour cranes
Treadwheel crane |
https://en.wikipedia.org/wiki/Animal%20engine | An animal engine is a machine powered by an animal. Horses, donkeys, oxen, dogs, and humans have all been used in this way. An unusual example of an animal engine was recorded at Portland, Victoria in 1866. A kangaroo had been tamed and trained to work a treadmill which drove various items of machinery.
See also
Experiment (horse powered boat)
Gin gang
Horse mill
Horse engine
Persian well
Treadwheel
Turnspit dog
Books
Animal Powered Machines, J. Kenneth Major. Shire Album 128 - Shire Publications 1985. |
https://en.wikipedia.org/wiki/Eizo | is a Japanese visual technology company, founded in March 1968, which manufactures display products and other solutions for markets such as business, healthcare, graphics, air traffic control, and maritime. The company is headquartered in Hakusan, Ishikawa Prefecture.
Name
The name EIZO, pronounced AY-ZO, comes from the Japanese kanji meaning "image" ( ).
History
Nanao Electric Co., Ltd. was founded in Fukui, Ishikawa prefecture in 1967. The following year, Hakui Electronic Corporation was founded in Hakui, Ishikawa; it initially manufactured televisions. In March 1973, it became Nanao Corporation.
In 1976, the company began to manufacture industrial monitors, and in 1978 it entered the gaming market by manufacturing CRTs arcade game cabinets of Space Invaders and selling tabletop video arcade machines.
In 1980, the company acquired video game developer and publisher Irem Corporation. In 1981, production of computer monitors, video cassette recorders and radio cassette TVs, with a new factory opening in Hakusan.
In 1984 the company began expanding overseas, distributing in Europe under the brand EIZO, with Hitec Associates Ltd established as a sales subsidiary specifically for the European market, and Nanao USA in California, United States, to launch products in that region under the same "Nanao" brand as in Japan. "EIZO" was launched as a brand of Hitec Associates in Europe in 1985, with the European arm was renamed as the Eizo Corporation in January 1990.
In 1990, the company's headquarters moved to Mattō, Ishikawa, with production and sales of computer monitors under the brand NANAO beginning the following year. In 1996, the brand was unified under the name EIZO.
In 1997, Irem Software Engineering Inc. was established, as a subsidiary company replacing Irem Corporation. The following couple of years saw the introduction of the FlexScan L23 13.8 LCD monitor and the FlexScan L66, the world first 1280 x 1024 resolution monitor. In 1999, Nanao Corporation a |
https://en.wikipedia.org/wiki/Recursive%20Bayesian%20estimation | In probability theory, statistics, and machine learning, recursive Bayesian estimation, also known as a Bayes filter, is a general probabilistic approach for estimating an unknown probability density function (PDF) recursively over time using incoming measurements and a mathematical process model. The process relies heavily upon mathematical concepts and models that are theorized within a study of prior and posterior probabilities known as Bayesian statistics.
In robotics
A Bayes filter is an algorithm used in computer science for calculating the probabilities of multiple beliefs to allow a robot to infer its position and orientation. Essentially, Bayes filters allow robots to continuously update their most likely position within a coordinate system, based on the most recently acquired sensor data. This is a recursive algorithm. It consists of two parts: prediction and innovation. If the variables are normally distributed and the transitions are linear, the Bayes filter becomes equal to the Kalman filter.
In a simple example, a robot moving throughout a grid may have several different sensors that provide it with information about its surroundings. The robot may start out with certainty that it is at position (0,0). However, as it moves farther and farther from its original position, the robot has continuously less certainty about its position; using a Bayes filter, a probability can be assigned to the robot's belief about its current position, and that probability can be continuously updated from additional sensor information.
Model
The measurements are the manifestations of a hidden Markov model (HMM), which means the true state is assumed to be an unobserved Markov process. The following picture presents a Bayesian network of a HMM.
Because of the Markov assumption, the probability of the current true state given the immediately previous one is conditionally independent of the other earlier states.
Similarly, the measurement at the k-th timestep is de |
https://en.wikipedia.org/wiki/Banach%20limit | In mathematical analysis, a Banach limit is a continuous linear functional defined on the Banach space of all bounded complex-valued sequences such that for all sequences , in , and complex numbers :
(linearity);
if for all , then (positivity);
, where is the shift operator defined by (shift-invariance);
if is a convergent sequence, then .
Hence, is an extension of the continuous functional where is the complex vector space of all sequences which converge to a (usual) limit in .
In other words, a Banach limit extends the usual limits, is linear, shift-invariant and positive. However, there exist sequences for which the values of two Banach limits do not agree. We say that the Banach limit is not uniquely determined in this case.
As a consequence of the above properties, a real-valued Banach limit also satisfies:
The existence of Banach limits is usually proved using the Hahn–Banach theorem (analyst's approach), or using ultrafilters (this approach is more frequent in set-theoretical expositions). These proofs necessarily use the axiom of choice (so called non-effective proof).
Almost convergence
There are non-convergent sequences which have a uniquely determined Banach limit. For example, if , then is a constant sequence, and
holds. Thus, for any Banach limit, this sequence has limit .
A bounded sequence with the property, that for every Banach limit the value is the same, is called almost convergent.
Banach spaces
Given a convergent sequence in , the ordinary limit of does not arise from an element of ,
if the duality is considered. The latter means is the continuous dual space (dual Banach space) of , and consequently, induces continuous linear functionals on , but not all.
Any Banach limit on is an example of an element of the dual Banach space of which is not in . The dual of is known as the ba space, and consists of all (signed) finitely additive measures on the sigma-algebra of all subsets of the natural numbers, o |
https://en.wikipedia.org/wiki/Left%20shift%20%28medicine%29 | Left shift or blood shift is an increase in the number of immature cell types among the blood cells in a sample of blood. Many (perhaps most) clinical mentions of left shift refer to the white blood cell lineage, particularly neutrophil-precursor band cells, thus signifying bandemia. Less commonly, left shift may also refer to a similar phenomenon in the red blood cell lineage in severe anemia, when increased reticulocytes and immature erythrocyte-precursor cells appear in the peripheral circulation.
Definition
The standard definition of a left shift is an absolute band form count greater than 7700/microL. There are competing explanations for the origin of the phrase "left shift," including the left-most button arrangement of early cell sorting machines and a 1920s publication by Josef Arneth, containing a graph in which immature neutrophils, with fewer segments, shifted the median left. In the latter view, the name reflects a curve's preponderance shifting to the left on a graph of hematopoietic cellular differentiations.
Morphology
It is usually noted on microscopic examination of a blood smear. This systemic effect of inflammation is most often seen in the course of an active infection and during other severe illnesses such as hypoxia and shock. Döhle bodies may also be present in the neutrophil's cytoplasm in the setting of sepsis or severe inflammatory responses.
Pathogenesis
It is believed that cytokines (including IL-1 and TNF) accelerate the release of cells from the postmitotic reserve pool in the bone marrow, leading to an increased number of immature cells.
See also
Leukocytosis
Reticulocyte |
https://en.wikipedia.org/wiki/Stone%20massage | The stone massage is a form of alternative medicine massage therapy and bodywork involving the placement of either heated or cooled stones to the body for the purpose of pain relief, relaxation and therapy. There are many variations and techniques used in the application of stone massage therapy, deriving from a variety of traditional practices. Stone massages are primarily used to alleviate physical pain issues, however, are also used to promote emotional and spiritual wellbeing in practice.
Origin and history
Stone massage and similar practices involving the placement of objects of different temperatures have been dated back to ancient civilisations as a form of healing and therapy. Cultures including Native American, Hawaiian and many South Pacific nations have practiced similar methods of ritual and technique to provide physical and spiritual ease. The traditional Hawaiian healing massage ‘Lomilomi’ involves the use of warmed Lomi stones in order to increase areas of blood flow in the body and provide a healing. Similar practices in China have also dated back 2000 years involving the use of heated stones to stimulate improved internal organ function. Such traditional practices have evolved and influenced the application of modern stone massage practices.
The re-emergence of such stone massage techniques was seen in 1993 by Mary Nelson with the development of a form of massage utilising hot and cold stones referred to as LaStone Therapy. This form of massage quickly rose to popularity becoming a multi-million dollar industry and has a strong focus on spiritual healing centering around chakras and energy channelling. Many massage therapy parlours providing stone massages offer LaStone Therapy due to its success amongst clients and the established reputable name for the process. These modern forms of stone massage combine techniques utilised in Swedish massage and deep tissue massage.
Technique
Volcanic stones, typically basalt are placed in hot water typic |
https://en.wikipedia.org/wiki/Heyawake | Heyawake (Japanese: へやわけ, "divided rooms") is a binary-determination logic puzzle published by Nikoli. As of 2013, five books consisting entirely of Heyawake puzzles have been published by Nikoli. It first appeared in Puzzle Communication Nikoli #39 (September 1992).
Rules
Heyawake is played on a rectangular grid of cells with no standard size; the grid is divided into variously sized rectangular "rooms" by bold lines following the edges of the cells. Some rooms may contain a single number, typically printed in their upper-left cell; as originally designed, every room was numbered, but this is rarely necessary for solving and is no longer followed.
Some of the cells in the puzzle are to be painted black; the object of the puzzle is to determine for each cell if it must be painted or must be left blank (remaining white). In practice, it is often easier to mark known "blank" cells in some way—for example, by placing a dot in the center of the cell.
The following rules determine which cells are which:
Rule 1: Painted cells may never be orthogonally connected (they may not share a side, although they can touch diagonally).
Rule 2: All white cells must be interconnected (form a single polyomino).
Rule 3: A number indicates exactly how many painted cells there must be in that particular room.
Rule 4: A room which has no number may contain any number of painted cells, or none.
Rule 5: Where a straight (orthogonal) line of connected white cells is formed, it must not contain cells from more than two rooms—in other words, any such line of white cells which connects three or more rooms is forbidden.
Solution methods
Note that the first two rules also apply to (for example) Hitori puzzles, and thus these puzzles share some of their solving methods:
If it is discovered that a cell is painted black, it is immediately known that all of the four (orthogonally) adjacent cells must be white (from Rule 1).
A section of (orthogonally) contiguous white cells cannot be cut off fro |
https://en.wikipedia.org/wiki/Protein%20subcellular%20localization%20prediction | Protein subcellular localization prediction (or just protein localization prediction) involves the prediction of where a protein resides in a cell, its subcellular localization.
In general, prediction tools take as input information about a protein, such as a protein sequence of amino acids, and produce a predicted location within the cell as output, such as the nucleus, Endoplasmic reticulum, Golgi apparatus, extracellular space, or other organelles. The aim is to build tools that can accurately predict the outcome of protein targeting in cells.
Prediction of protein subcellular localization is an important component of bioinformatics based prediction of protein function and genome annotation, and it can aid the identification of drug targets.
Background
Experimentally determining the subcellular localization of a protein can be a laborious and time consuming task. Immunolabeling or tagging (such as with a green fluorescent protein) to view localization using fluorescence microscope are often used. A high throughput alternative is to use prediction.
Through the development of new approaches in computer science, coupled with an increased dataset of proteins of known localization, computational tools can now provide fast and accurate localization predictions for many organisms. This has resulted in subcellular localization prediction becoming one of the challenges being successfully aided by bioinformatics, and machine learning.
Many prediction methods now exceed the accuracy of some high-throughput laboratory methods for the identification of protein subcellular localization. Particularly, some predictors have been developed that can be used to deal with proteins that may simultaneously exist, or move between, two or more different subcellular locations. Experimental validation is typically required to confirm the predicted localizations.
Tools
In 1999 PSORT was the first published program to predict subcellular localization. Subsequent tools and websites |
https://en.wikipedia.org/wiki/Ear%20%28botany%29 | An ear is the grain-bearing tip part of the stem of a cereal plant, such as wheat or maize (corn). It can also refer to "a prominent lobe in some leaves."
The ear is a spike, consisting of a central stem on which tightly packed rows of flowers grow. These develop into fruits containing the edible seeds. In corn (maize), an ear is protected by leaves called husks. Inside an ear of corn is a corncob.
In some species (including wheat), unripe ears contribute significantly to photosynthesis, in addition to the leaves lower down the plant.
A parasite known as Anguina tritici (Ear Cockle) specifically affects the ears on wheat and rye by destroying the tissues and stems during growth. The parasite has been eradicated in most countries (with the exception of North Africa and West Asia) by using the
crop rotation system. |
https://en.wikipedia.org/wiki/Israel%20Institute%20for%20Biological%20Research | Israel Institute for Biological Research (IIBR) is an Israeli research and development laboratory It is under the jurisdiction of the Prime Minister's Office that works in close cooperation with Israeli government agencies. IIBR has many public projects on which it works with international research organizations (governmental and non-governmental) and universities. It has approximately 350 employees, 150 of whom are scientists. Its research findings are often published in national and international scientific publications. It is widely believed to be involved in the manufacturing of biological and chemical weapons. The IIBR is currently developing a COVID-19 vaccine Brilife.
History
IIBR originated with Hemed Bet, the Haganah biological warfare unit, which Alexander Kenyan, then a microbiology student, established in Jaffa in February 1948, shortly before Israeli independence, at the direction of Yigael Yadin, the Haganah's chief operations officer. Ephraim Katzir was Hemed Bet's first commander.
The institute in its current form was founded in 1952, after Hemed Bet relocated to an orange grove near Ness Ziona. It was founded partly in a former Palestinian mansion of Wadi Hunayn. Among the founders were Professor Ernst David Bergmann, Prime Minister David Ben-Gurion's science adviser and the head of R&D at the Ministry of Defense. Keynan was IIBR's first director.
Some of the fields in which IIBR conducts research include:
Medical diagnostic techniques
Mechanisms of pathogenic diseases
Vaccines and pharmaceuticals
Protein and enzyme synthesis and engineering
Process biotechnology
Air pollution risk assessment
Environmental detectors and biosensors
The institute is widely suspected of being involved in developing chemical and biological weapons. It is also assumed that the Institute develops vaccines and antidotes for such weapons. While refusing to confirm it, Israel is widely suspected of having developed offensive biological and chemical weapons ca |
https://en.wikipedia.org/wiki/Joomla | Joomla (), also spelled Joomla! (with an exclamation mark) and sometimes abbreviated as J!, is a free and open-source content management system (CMS) for publishing web content on websites. Web content applications include discussion forums, photo galleries, e-Commerce and user communities and numerous other web-based applications. Joomla is developed by a community of volunteers supported with the legal, organisational and financial resources of Open Source Matters, Inc.
Joomla is written in Hypertext Preprocessor (PHP), uses object-oriented programming techniques and software design patterns, and stores data in a Structured Query Language (MySQL) database. It has a software dependency on the Symfony PHP framework. Joomla includes features such as page caching, RSS feeds, blogs, search, and support for language internationalisation. It is built on a model–view–controller web application framework that can be used independently of the CMS.
Around 6,000 extensions are available from the Joomla website, and more are available from other sources. As of 2022, it was estimated to be the fifth most used CMS on the Internet, after WordPress, Shopify, Wix and Squarespace.
Overview
Joomla has a web template system using a template processor. Its architecture is a front controller, routing all requests for non-static URIs via PHP which parses the URI and identifies the target page. This allows support for more human-readable permalinks. The controller manages both the frontend, public-facing view, and a backend (GUI-driven) administration interface. The administration interface (a) stores management and content information within a database, and (b) maintains a configuration file (, usually located in the file system root of the Joomla installation). The configuration file provides the connection between the server, database and file system and facilitates migrating the website from one server to another.
The backend interface allows website operators to manage use |
https://en.wikipedia.org/wiki/Cycles%20per%20instruction | In computer architecture, cycles per instruction (aka clock cycles per instruction, clocks per instruction, or CPI) is one aspect of a processor's performance: the average number of clock cycles per instruction for a program or program fragment. It is the multiplicative inverse of instructions per cycle.
Definition
The average of Cycles Per Instruction in a given process () is defined by the following weighted average:
Where is the number of instructions for a given instruction type , is the clock-cycles for that instruction type and is the total instruction count. The summation sums over all instruction types for a given benchmarking process.
Explanation
Let us assume a classic RISC pipeline, with the following five stages:
Instruction fetch cycle (IF).
Instruction decode/Register fetch cycle (ID).
Execution/Effective address cycle (EX).
Memory access (MEM).
Write-back cycle (WB).
Each stage requires one clock cycle and an instruction passes through the stages sequentially. Without pipelining, in a multi-cycle processor, a new instruction is fetched in stage 1 only after the previous instruction finishes at stage 5, therefore the number of clock cycles it takes to execute an instruction is five (CPI = 5 > 1). In this case, the processor is said to be subscalar. With pipelining, a new instruction is fetched every clock cycle by exploiting instruction-level parallelism, therefore, since one could theoretically have five instructions in the five pipeline stages at once (one instruction per stage), a different instruction would complete stage 5 in every clock cycle and on average the number of clock cycles it takes to execute an instruction is 1 (CPI = 1). In this case, the processor is said to be scalar.
With a single-execution-unit processor, the best CPI attainable is 1. However, with a multiple-execution-unit processor, one may achieve even better CPI values (CPI < 1). In this case, the processor is said to be superscalar. To get better CPI value |
https://en.wikipedia.org/wiki/Planetary%20habitability | Planetary habitability is the measure of a planet's or a natural satellite's potential to develop and maintain environments hospitable to life. Life may be generated directly on a planet or satellite endogenously or be transferred to it from another body, through a hypothetical process known as panspermia. Environments do not need to contain life to be considered habitable nor are accepted habitable zones (HZ) the only areas in which life might arise.
As the existence of life beyond Earth is unknown, planetary habitability is largely an extrapolation of conditions on Earth and the characteristics of the Sun and Solar System which appear favorable to life's flourishing. Of particular interest are those factors that have sustained complex, multicellular organisms on Earth and not just simpler, unicellular creatures. Research and theory in this regard is a component of a number of natural sciences, such as astronomy, planetary science and the emerging discipline of astrobiology.
An absolute requirement for life is an energy source, and the notion of planetary habitability implies that many other geophysical, geochemical, and astrophysical criteria must be met before an astronomical body can support life. In its astrobiology roadmap, NASA has defined the principal habitability criteria as "extended regions of liquid water, conditions favorable for the assembly of complex organic molecules, and energy sources to sustain metabolism". In August 2018, researchers reported that water worlds could support life.
Habitability indicators and biosignatures must be interpreted within a planetary and environmental context. In determining the habitability potential of a body, studies focus on its bulk composition, orbital properties, atmosphere, and potential chemical interactions. Stellar characteristics of importance include mass and luminosity, stable variability, and high metallicity. Rocky, wet terrestrial-type planets and moons with the potential for Earth-like chemistry ar |
https://en.wikipedia.org/wiki/Institute%20of%20Biochemistry%20and%20Biophysics | The Institute of Biochemistry and Biophysics (IBB)
is a pioneering Iranian research institute founded in 1976 to conduct world class research in cellular and molecular biology. It is affiliated with University of Tehran and is located in the university campus.
IBB is an educational and research oriented center for training postgraduate students both nationally and internationally. Interdisciplinary research is one of the main themes at the institute.
History
At first, IBB was known as the Department of Cellular and Molecular Biology, but later separated to three departments of Biochemistry, Biophysics and Bioinformatics as will be described below. Master's degrees in Biochemistry and Biophysics were established in 1986 and 1990, respectively and PhD degrees in Biochemistry and Biophysics were established in 1989 and 1996, respectively. Initially IBB was divided into two independent educational groups of Biochemistry and Biophysics in 2002. The department of Bioinformatics was established in 2005 just for training Ph.D. students.
Research and Facilities
Currently, IBB is composed of three departments of Biochemistry, Biophysics and Bioinformatics with 21 full-time faculty members of which 10 members are Professors. The department also has 35 administrative staff members. IBB has 17 research laboratories, a general communal use equipments laboratory, a greenhouse, an animal house, a number of computer laboratories, a library and a restaurant.
National and international forum affiliated at IBB:
1. IBB is an affiliated Center of The World Academy of Science(TWAS) in Iran
2. Iranian Secretariat of UNESCO chair on Interdisciplinary Research in Diabetes, (UCIRD) located at IBB
3. Iranian Secretariat of the International Union of Biochemistry and Molecular Biology (IUBMB) located at IBB
4. Iranian Secretariat of the Federation of Asian and Oceanian Biochemists and Molecular Biologists (FAOBMB)
5.Center of Excellence in Biothermodynamics (CEBiotherm) is located at |
https://en.wikipedia.org/wiki/History%20of%20Apple%20Inc. | Apple Inc., originally named Apple Computer, Inc., is a multinational corporation that creates and markets consumer electronics and attendant computer software, and is a digital distributor of media content. Apple's core product lines are the iPhone smartphone, iPad tablet computer, and the Macintosh personal computer. The company offers its products online and has a chain of retail stores known as Apple Stores. Founders Steve Jobs, Steve Wozniak, and Ronald Wayne created Apple Computer Co. on April 1, 1976, to market Wozniak's Apple I desktop computer, and Jobs and Wozniak incorporated the company on January 3, 1977, in Cupertino, California.
For more than three decades, Apple Computer was predominantly a manufacturer of personal computers, including the Apple II, Macintosh, and Power Mac lines, but it faced rocky sales and low market share during the 1990s. Jobs, who had been ousted from the company in 1985, returned to Apple in 1997 after his company NeXT was bought by Apple. The following year he became the company's interim CEO, which later became permanent. Jobs subsequently instilled a new corporate philosophy of recognizable products and simple design, starting with the original iMac in 1998.
With the introduction of the successful iPod music player in 2001 and iTunes Music Store in 2003, Apple established itself as a leader in the consumer electronics and media sales industries, leading it to drop "Computer" from the company's name in 2007. The company is also known for its iOS range of smart phone, media player, and tablet computer products that began with the iPhone, followed by the iPod Touch and then iPad. As of June 30, 2015, Apple was the largest publicly traded corporation in the world by market capitalization, with an estimated value of US$1 trillion as of August 2, 2018. Apple's worldwide annual revenue in 2010 totaled US$65 billion, growing to US$127.8 billion in 2011 and $156 billion in 2012.
1971–1985: Jobs and Wozniak
Pre-foundation
Steve |
https://en.wikipedia.org/wiki/Simple%20linear%20regression | In statistics, simple linear regression is a linear regression model with a single explanatory variable. That is, it concerns two-dimensional sample points with one independent variable and one dependent variable (conventionally, the x and y coordinates in a Cartesian coordinate system) and finds a linear function (a non-vertical straight line) that, as accurately as possible, predicts the dependent variable values as a function of the independent variable.
The adjective simple refers to the fact that the outcome variable is related to a single predictor.
It is common to make the additional stipulation that the ordinary least squares (OLS) method should be used: the accuracy of each predicted value is measured by its squared residual (vertical distance between the point of the data set and the fitted line), and the goal is to make the sum of these squared deviations as small as possible. Other regression methods that can be used in place of ordinary least squares include least absolute deviations (minimizing the sum of absolute values of residuals) and the Theil–Sen estimator (which chooses a line whose slope is the median of the slopes determined by pairs of sample points). Deming regression (total least squares) also finds a line that fits a set of two-dimensional sample points, but (unlike ordinary least squares, least absolute deviations, and median slope regression) it is not really an instance of simple linear regression, because it does not separate the coordinates into one dependent and one independent variable and could potentially return a vertical line as its fit.
The remainder of the article assumes an ordinary least squares regression.
In this case, the slope of the fitted line is equal to the correlation between and corrected by the ratio of standard deviations of these variables. The intercept of the fitted line is such that the line passes through the center of mass of the data points.
Fitting the regression line
Consider the model function
|
https://en.wikipedia.org/wiki/Gaisi%20Takeuti | was a Japanese mathematician, known for his work in proof theory.
After graduating from Tokyo University, he went to Princeton to study under Kurt Gödel.
He later became a professor at the University of Illinois at Urbana–Champaign. Takeuti was president (2003–2009) of the Kurt Gödel Society, having worked on the book Memoirs of a Proof Theorist: Godel and Other Logicians. His goal was to prove the consistency of the real numbers. To this end, Takeuti's conjecture speculates that a sequent formalisation of second-order logic has cut-elimination. He is also known for his work on ordinal diagrams with Akiko Kino.
Publications
2013 Dover reprint
Notes
External links
Presidents of the Kurt Gödel Society
Takeuti Symposium (contains relevant birthdate information)
1926 births
2017 deaths
Japanese logicians
Japanese philosophers
Proof theorists
University of Tokyo alumni
University of Illinois Urbana-Champaign faculty |
https://en.wikipedia.org/wiki/Lanczos%20algorithm | The Lanczos algorithm is an iterative method devised by Cornelius Lanczos that is an adaptation of power methods to find the "most useful" (tending towards extreme highest/lowest) eigenvalues and eigenvectors of an Hermitian matrix, where is often but not necessarily much smaller than . Although computationally efficient in principle, the method as initially formulated was not useful, due to its numerical instability.
In 1970, Ojalvo and Newman showed how to make the method numerically stable and applied it to the solution of very large engineering structures subjected to dynamic loading. This was achieved using a method for purifying the Lanczos vectors (i.e. by repeatedly reorthogonalizing each newly generated vector with all previously generated ones) to any degree of accuracy, which when not performed, produced a series of vectors that were highly contaminated by those associated with the lowest natural frequencies.
In their original work, these authors also suggested how to select a starting vector (i.e. use a random-number generator to select each element of the starting vector) and suggested an empirically determined method for determining , the reduced number of vectors (i.e. it should be selected to be approximately 1.5 times the number of accurate eigenvalues desired). Soon thereafter their work was followed by Paige, who also provided an error analysis. In 1988, Ojalvo produced a more detailed history of this algorithm and an efficient eigenvalue error test.
The algorithm
Input a Hermitian matrix of size , and optionally a number of iterations (as default, let ).
Strictly speaking, the algorithm does not need access to the explicit matrix, but only a function that computes the product of the matrix by an arbitrary vector. This function is called at most times.
Output an matrix with orthonormal columns and a tridiagonal real symmetric matrix of size . If , then is unitary, and .
Warning The Lanczos iteration is prone to numerical instability |
https://en.wikipedia.org/wiki/Bernard%20Tucker%20Medal | The Bernard Tucker Medal is awarded by the British Trust for Ornithology for services to ornithology. It is named in memory of Bernard Tucker, their first Secretary. It has been awarded since 1954, usually annually although there are some years when no medals were awarded.
Bernard Tucker Medallists
Source: British Trust for Ornithology
20th Century
21st Century
See also
List of ornithology awards
External links
Past medallists
Ornithology awards
British Trust for Ornithology
1954 establishments in the United Kingdom
Awards established in 1954 |
https://en.wikipedia.org/wiki/Langmuir%20%28unit%29 | The langmuir (symbol: L) is a unit of exposure (or dosage) to a surface (e.g. of a crystal) and is used in ultra-high vacuum (UHV) surface physics to study the adsorption of gases. It is a practical unit, and is not dimensionally homogeneous, and so is used only in this field. It is named after American physicist Irving Langmuir.
Definition
The langmuir is defined by multiplying the pressure of the gas by the time of exposure. One langmuir corresponds to an exposure of 10−6 Torr during one second. For example, exposing a surface to a gas pressure of 10−8 Torr for 100 seconds corresponds to 1 L.
Similarly, keeping the pressure of oxygen gas at 2.5·10−6 Torr for 40 seconds will give a dose of 100 L.
Conversion
Since both different pressures and exposure times can give the same langmuir (see Definition) it can be difficult to convert Langmuir (L) to exposure pressure × time (Torr·s) and vice versa. The following equation can be used to easily convert between the two: Here, and are any two numbers whose product equals the desired Langmuir value, is an integer allowing different magnitudes of pressure or exposure time to be used in conversion. The units are represented in the [square brackets]. Using the prior example, for a dose of 100 L a pressure of 2.5 × 10−6 Torr can be applied for 40 seconds, thus, , and . However, this dosage could also be gained with 8 × 10−8 Torr for 1250 seconds, here , , . In both scenarios .
Derivation
Exposure of a surface in surface physics is a type of fluence, that is the integral of number flux (JN) with respect to exposed time (t) to give a number of particles per unit area (Φ):
The number flux for an ideal gas, that is the number of gas molecules passing through (in a single direction) a surface of unit area in unit time, can be derived from kinetic theory:
where C is the number density of the gas, and is the mean speed of the molecules (not the root-mean-square speed, although the two are related). The number density of a |
https://en.wikipedia.org/wiki/Psoralen | Psoralen (also called psoralene) is the parent compound in a family of naturally occurring organic compounds known as the linear furanocoumarins. It is structurally related to coumarin by the addition of a fused furan ring, and may be considered as a derivative of umbelliferone. Psoralen occurs naturally in the seeds of Psoralea corylifolia, as well as in the common fig, celery, parsley, West Indian satinwood, and in all citrus fruits. It is widely used in PUVA (psoralen + UVA) treatment for psoriasis, eczema, vitiligo, and cutaneous T-cell lymphoma; these applications are typically through the use of medications such as Methoxsalen. Many furanocoumarins are extremely toxic to fish, and some are deposited in streams in Indonesia to catch fish.
Uses
Psoralen is a mutagen, and is used for this purpose in molecular biology research. Psoralen intercalates into DNA and on exposure to ultraviolet (UVA) radiation can form monoadducts and covalent interstrand cross-links (ICL) with thymines, preferentially at 5'-TpA sites in the genome, inducing apoptosis. Psoralen plus UVA (PUVA) therapy can be used to treat hyperproliferative skin disorders like psoriasis and certain kinds of skin cancer. Unfortunately, PUVA treatment itself leads to a higher risk of skin cancer.
An important use of psoralen is in PUVA treatment for skin problems such as psoriasis and, to a lesser extent, eczema and vitiligo. This takes advantage of the high UV absorbance of psoralen. The psoralen is applied first to sensitise the skin, then UVA light is applied to clean up the skin problem. Psoralens are also used in photopheresis, where they are mixed with the extracted leukocytes before UV radiation is applied.
Despite the photocarcinogenic properties of psoralen, it was used as a tanning activator in sunscreens until 1996. Psoralens are used in tanning accelerators, because psoralen increases the skin's sensitivity to light. Some patients have had severe skin loss after sunbathing with psoralen- |
https://en.wikipedia.org/wiki/List%20of%20assigned%20/8%20IPv4%20address%20blocks | Some large blocks of IPv4 addresses, the former Class A network blocks, are assigned in whole to single organizations or related groups of organizations, either by the Internet Corporation for Assigned Names and Numbers (ICANN), through the Internet Assigned Numbers Authority (IANA), or a regional Internet registry.
Each block contains 256 = 2 = 16,777,216 addresses, which covers the whole range of the last three delimited segments of an IP address.
As IPv4 address exhaustion has advanced to its final stages, some organizations, such as Stanford University, formerly using , have returned their allocated blocks (in this case to APNIC) to assist in the delay of the exhaustion date.
List of reserved /8 blocks
List of assigned /8 blocks to commercial organisations
List of assigned /8 blocks to the United States Department of Defense
List of assigned /8 blocks to the regional Internet registries
The regional Internet registries (RIR) allocate IPs within a particular region of the world.
Note that this list may not include current assignments of /8 blocks to all regional or national Internet registries.
Original list of IPv4 assigned address blocks
The original list of IPv4 address blocks was published in September 1981. In previous versions of the document, network numbers were 8-bit numbers rather than the 32-bit numbers used in IPv4. At that time, three networks were added that were not listed earlier: 42.rrr.rrr.rrr, 43.rrr.rrr.rrr, and 44.rrr.rrr.rrr.
The relevant portion of RFC 790 is reproduced here with minor changes:
000.rrr.rrr.rrr Reserved [JBP]
001.rrr.rrr.rrr BBN-PR BBN Packet Radio Network [DCA2]
002.rrr.rrr.rrr SF-PR-1 SF Packet Radio Network [JEM]
003.rrr.rrr.rrr BBN-RCC BBN RCC Network [SGC]
004.rrr.rrr.rrr SATNET Atlantic Satellite Network [DM11]
005.rrr.rrr.rrr SILL-PR Ft. Sill Packet Radio Network[JEM]
006.rrr.rrr.rrr SF-PR-2 SF Packet Radio Network [JEM]
007.rrr.rrr.rrr CHAOS MIT CHAOS Network [MOON]
008.rrr.rrr.rrr CLARKNET SA |
https://en.wikipedia.org/wiki/Pierpont%20prime | In number theory, a Pierpont prime is a prime number of the form
for some nonnegative integers and . That is, they are the prime numbers for which is 3-smooth. They are named after the mathematician James Pierpont, who used them to characterize the regular polygons that can be constructed using conic sections. The same characterization applies to polygons that can be constructed using ruler, compass, and angle trisector, or using paper folding.
Except for 2 and the Fermat primes, every Pierpont prime must be 1 modulo 6. The first few Pierpont primes are:
It has been conjectured that there are infinitely many Pierpont primes, but this remains unproven.
Distribution
A Pierpont prime with is of the form , and is therefore a Fermat prime (unless ). If is positive then must also be positive (because would be an even number greater than 2 and therefore not prime), and therefore the non-Fermat Pierpont primes all have the form , when is a positive integer (except for 2, when ).
Empirically, the Pierpont primes do not seem to be particularly rare or sparsely distributed; there are 42 Pierpont primes less than 106, 65 less than 109, 157 less than 1020, and 795 less than 10100. There are few restrictions from algebraic factorisations on the Pierpont primes, so there are no requirements like the Mersenne prime condition that the exponent must be prime. Thus, it is expected that among -digit numbers of the correct form , the fraction of these that are prime should be proportional to , a similar proportion as the proportion of prime numbers among all -digit numbers.
As there are numbers of the correct form in this range, there should be Pierpont primes.
Andrew M. Gleason made this reasoning explicit, conjecturing there are infinitely many Pierpont primes, and more specifically that there should be approximately Pierpont primes up to . According to Gleason's conjecture there are Pierpont primes smaller than N, as opposed to the smaller conjectural number of |
https://en.wikipedia.org/wiki/Portevin%E2%80%93Le%20Chatelier%20effect | The Portevin–Le Chatelier (PLC) effect describes a serrated stress–strain curve or jerky flow, which some materials exhibit as they undergo plastic deformation, specifically inhomogeneous deformation. This effect has been long associated with dynamic strain aging or the competition between diffusing solutes pinning dislocations and dislocations breaking free of this stoppage.
The onset of the PLC effect occurs when the strain rate sensitivity becomes negative and inhomogeneous deformation starts. This effect also can appear on the specimen's surface and in bands of plastic deformation. This process starts at a so-called critical strain, which is the minimum strain needed for the onset of the serrations in the stress–strain curve. The critical strain is both temperature and strain rate dependent. The existence of a critical strain is attributed to better solute diffusivity due to the deformation created vacancies and increased mobile dislocation density. Both of these contribute to the instability in substitutional alloys, while interstitial alloys are only affected by the increase in mobile dislocation densities.
History
While the effect is named after Albert Portevin and François Le Chatelier, they were not the first to discover it. Félix Savart made the discovery when he observed non-homogeneous deformation during a tensile test of copper strips. He documented the physical serrations in his samples that are currently known as Portevin–Le Chatelier bands. A student of Savart, Antoine Masson, repeated the experiment while controlling for loading rate. Masson observed that under a constant loading rate, the samples would experience sudden large changes in elongation (as large as a few millimeters).
Underlying physics
Much of the underlying physics of the Portevin-Le Chatelier effect lies in a specific case of solute drag creep. Adding solute atoms to a pure crystal introduces a size misfit into the system. This size misfit leads to restriction of dislocation mo |
https://en.wikipedia.org/wiki/Determinacy | Determinacy is a subfield of set theory, a branch of mathematics, that examines the conditions under which one or the other player of a game has a winning strategy, and the consequences of the existence of such strategies. Alternatively and similarly, "determinacy" is the property of a game whereby such a strategy exists. Determinacy was introduced by Gale and Stewart in 1950, under the name "determinateness".
The games studied in set theory are usually Gale–Stewart games—two-player games of perfect information in which the players make an infinite sequence of moves and there are no draws. The field of game theory studies more general kinds of games, including games with draws such as tic-tac-toe, chess, or infinite chess, or games with imperfect information such as poker.
Basic notions
Games
The first sort of game we shall consider is the two-player game of perfect information of length ω, in which the players play natural numbers. These games are often called Gale–Stewart games.
In this sort of game there are two players, often named I and II, who take turns playing natural numbers, with I going first. They play "forever"; that is, their plays are indexed by the natural numbers. When they're finished, a predetermined condition decides which player won. This condition need not be specified by any definable rule; it may simply be an arbitrary (infinitely long) lookup table saying who has won given a particular sequence of plays.
More formally, consider a subset A of Baire space; recall that the latter consists of all ω-sequences of natural numbers. Then in the game GA,
I plays a natural number a0, then II plays a1, then I plays a2, and so on. Then I wins the game if and only if
and otherwise II wins. A is then called the payoff set of GA.
It is assumed that each player can see all moves preceding each of his moves, and also knows the winning condition.
Strategies
Informally, a strategy for a player is a way of playing in which his plays are entirely |
https://en.wikipedia.org/wiki/Ischiopagi | Ischiopagi comes from the Greek word ischio- meaning hip (ilium) and -pagus meaning fixed or united. It is the medical term used for conjoined twins (Class V) who are united at the pelvis. The twins are classically joined with the vertebral axis at 180°. The conjoined twins usually have four arms; two, three or four legs; and typically one external genitalia and anus.
It is mostly confused with pygopagus where the twins are joined dorsally at the buttocks facing away from each other, whereas ischiopagus twins are joined ventrally and caudally at the sacrum and coccyx. Parapagus is also similar to ischiopagus; however, parapagus twins are joined side-by-side whereas ischiopagus twins typically have spines connected at a 180° angle, facing away from one another.
Classification
Ischiopagus Dipus: This is the rarest variety with the twins sharing two legs with no lower extremities on one side.
Ischiopagus Tripus: These twins share three legs, the third leg is often two fused legs, or is non-functioning. The twins also usually share only one set of external genitalia.
Ischiopagus Tetrapus/Quadripus: This variety has the twins at a symmetrical continuous longitudinal axis with their area of union not broken anteriorly. The axes extends in a straight line but in opposite directions. The lower extremities are oriented at right angles to the axes of the thorax and the adjacent limbs near the union of the ischium belong to the opposite twin.
Embryology
During embryonic development, twins can form from the splitting of a single embryo (monozygotic) which forms identical twins or the twins can arise from separate oocytes in the same menstrual cycle (dizygotic) which forms fraternal twins. Although the latter is more frequent, monozygotic is the reason conjoined twins can develop. In monozygotic twinning for conjoined twins such as ischiopagi, the twins form by the splitting of a bi-laminar embryonic disc after the formation of the inner cell masses. Thus, making the twins |
https://en.wikipedia.org/wiki/Shock%20response%20spectrum | A Shock Response Spectrum (SRS) is a graphical representation of a shock, or any other transient acceleration input, in terms of how a Single Degree Of Freedom (SDOF) system (like a mass on a spring) would respond to that input. The horizontal axis shows the natural frequency of a hypothetical SDOF, and the vertical axis shows the peak acceleration which this SDOF would undergo as a consequence of the shock input.
Calculation
The most direct and intuitive way to generate an SRS from a shock waveform is the following procedure:
Pick a damping ratio (or equivalently, a quality factor Q) for your SRS to be based on;
Pick a frequency f, and assume that there is a hypothetical Single Degree of Freedom (SDOF) system with a damped natural frequency of f ;
Calculate (by direct time-domain simulation) the maximum instantaneous absolute acceleration experienced by the mass element of your SDOF at any time during (or after) exposure to the shock in question. This acceleration is a;
Draw a dot at (f,a);
Repeat steps 2–4 for many other values of f, and connect all the dots together into a smooth curve.
The resulting plot of peak acceleration vs test system frequency is called a Shock Response Spectrum. It is often plotted with frequency in Hz, and with acceleration in units of g
Example application
Consider a computer chassis containing three cards with fundamental natural frequencies of f1, f2, and f3. Lab tests have previously confirmed that this system survives a certain shock waveform—say, the shock from dropping the chassis from 2 feet above a hard floor. Now, the customer wants to know whether the system will survive a different shock waveform—say, from dropping the chassis from 4 feet above a carpeted floor. If the SRS of the new shock is lower than the SRS of the old shock at each of the three frequencies f1, f2, and f3, then the chassis is likely to survive the new shock. (It is not, however, guaranteed.)
Details and limitations
Any transient waveform can b |
https://en.wikipedia.org/wiki/Expected%20value%20of%20perfect%20information | In decision theory, the expected value of perfect information (EVPI) is the price that one would be willing to pay in order to gain access to perfect information. A common discipline that uses the EVPI concept is health economics. In that context and when looking at a decision of whether to adopt a new treatment technology, there is always some degree of uncertainty surrounding the decision, because there is always a chance that the decision turns out to be wrong. The expected value of perfect information analysis tries to measure the expected cost of that uncertainty, which “can be interpreted as the expected value of perfect information (EVPI), since perfect information can eliminate the possibility of making the wrong decision” at least from a theoretical perspective.
Equation
The problem is modeled with a payoff matrix Rij in which the row index i describes a choice that must be made by the player, while the column index j describes a random variable that the player does not yet have knowledge of, that has probability pj of being in state j. If the player is to choose i without knowing the value of j, the best choice is the one that maximizes the expected monetary value:
where
is the expected payoff for action i i.e. the expectation value, and
is choosing the maximum of these expectations for all available actions.
On the other hand, with perfect knowledge of j, the player may choose a value of i that optimizes the expectation for that specific j. Therefore, the expected value given perfect information is
where is the probability that the system is in state j, and is the pay-off if one follows action i while the system is in state j.
Here, indicates the best choice of action i for each state j.
The expected value of perfect information is the difference between these two quantities,
This difference describes, in expectation, how much larger a value the player can hope to obtain by knowing j and picking the best i for that j, as compared to picking a v |
https://en.wikipedia.org/wiki/Balseiro%20Institute | Balseiro Institute () is an Argentine academic institution that belongs partially to the National University of Cuyo and partially to the National Atomic Energy Commission. It is located in Bariloche, Río Negro province, Argentina. Notable alumni of this institute include Marcela Carena, Juan Maldacena, Juan Ignacio Galvan and Jorge Pullin.
Overview
The Balseiro Institute teaches Physics, Nuclear Engineering, Mechanical Engineering and Telecommunications Engineering at undergraduate and graduate levels. The institute admits students who have completed two years of university studies (either in Physics or Engineering) and undergoes a rigorous admission procedure.
It's considered the best Experimental Physics and Nuclear Engineering study centre of Latin America, as well as a very prestigious one worldwide.
This is a free public institution with a number of features that make it unique. It was created in 1955 and it was formalized in the agreement signed between the National Atomic Energy Commission (CNEA) and the National University of Cuyo (UNCuyo). Its objectives are reflected in the Resolution of the Rectorate 0445 of 1999, where both parties reiterate their willingness to jointly formulate the academic policy of the Balseiro Institute, joining forces in order to contribute jointly to the training of specialists in Sciences and Engineering and renew their objective to contribute to the research and development of activities that meet the interests of the country, through UNIVERSITY and CNEA. At the same time, the Balseiro Institute is an academic unit integrated to the Centro Atómico Bariloche (CAB), which has state-of-the-art research and development laboratories to which IB students have access to practice.
It is noteworthy that all IB students receive full scholarships, allowing them a full dedication to the study. This, among other distinctive aspects, allows students of IB degree, master and postgraduate degrees to gain advanced training in both theoretica |
https://en.wikipedia.org/wiki/Hypoxemia | Hypoxemia is an abnormally low level of oxygen in the blood. More specifically, it is oxygen deficiency in arterial blood. Hypoxemia has many causes, and often causes hypoxia as the blood is not supplying enough oxygen to the tissues of the body.
Definition
Hypoxemia refers to the low level of oxygen in blood, and the more general term hypoxia is an abnormally low oxygen content in any tissue or organ, or the body as a whole. Hypoxemia can cause hypoxia (hypoxemic hypoxia), but hypoxia can also occur via other mechanisms, such as anemia.
Hypoxemia is usually defined in terms of reduced partial pressure of oxygen (mm Hg) in arterial blood, but also in terms of reduced content of oxygen (ml oxygen per dl blood) or percentage saturation of hemoglobin (the oxygen-binding protein within red blood cells) with oxygen, which is either found singly or in combination.
While there is general agreement that an arterial blood gas measurement which shows that the partial pressure of oxygen is lower than normal constitutes hypoxemia, there is less agreement concerning whether the oxygen content of blood is relevant in determining hypoxemia. This definition would include oxygen carried by hemoglobin. The oxygen content of blood is thus sometimes viewed as a measure of tissue delivery rather than hypoxemia.
Just as extreme hypoxia can be called anoxia, extreme hypoxemia can be called anoxemia.
Signs and symptoms
In an acute context, hypoxemia can cause symptoms such as those in respiratory distress. These include breathlessness, an increased rate of breathing, use of the chest and abdominal muscles to breathe, and lip pursing.
Chronic hypoxemia may be compensated or uncompensated. The compensation may cause symptoms to be overlooked initially, however, further disease or a stress such as any increase in oxygen demand may finally unmask the existing hypoxemia. In a compensated state, blood vessels supplying less-ventilated areas of the lung may selectively contract, to redirec |
https://en.wikipedia.org/wiki/Cipher%20Bureau%20%28film%29 | Cipher Bureau is a 1938 American film directed by Charles Lamont. The film was successful enough to elicit a sequel, Panama Patrol.
Plot
Philip Waring, the head of a listening agency in Washington D.C., is dedicated to breaking up a foreign radio-spy ring. He enlists his naval-officer brother and tangles with beautiful spies.
Cast
Leon Ames as Philip Waring
Charlotte Wynters as Helen Lane
Joan Woodbury as Therese Brahm
Don Dillaway as Paul Waring
Gustav von Seyffertitz as Albert Grood
Tenen Holtz as Simon Herrick
Walter Bonn as Anton Decker
Si Wills as Lt. Clarke
George Lynn as Lt. Tydall
Jason Robards as Ellsworth
Sidney Miller as Jimmy
Hooper Atchley as Commander Nash
Robert Frazer as Paul's counsel
External links
Turner Classic Movies page
1938 films
American black-and-white films
Films directed by Charles Lamont
Grand National Films films
1938 drama films
American drama films
Cryptography in fiction
1930s English-language films
1930s American films |
https://en.wikipedia.org/wiki/NDMP | NDMP, or Network Data Management Protocol, is a protocol meant to transport data between network attached storage (NAS) devices and backup devices. This removes the need for transporting the data through the backup server itself, thus enhancing speed and removing load from the backup server. It was originally invented by NetApp and Intelliguard, acquired by Legato and then EMC Corporation. Currently, the Storage Networking Industry Association (SNIA) oversees the development of the protocol.
Most contemporary multi-platform backup software support this protocol.
External links
NDMP at the SNIA web site
TechTarget -- NDMP definition
Backup
Network protocols
Network-attached storage |
https://en.wikipedia.org/wiki/Felix%20Bernstein%20%28mathematician%29 | Felix Bernstein (24 February 1878 in Halle, Germany – 3 December 1956 in Zürich, Switzerland), was a German Jewish mathematician known for proving in 1896 the Schröder–Bernstein theorem, a central result in set theory, and less well known for demonstrating in 1924 the correct blood group inheritance pattern of multiple alleles at one locus through statistical analysis.
Life
Felix Bernstein was born in 1878 to a Jewish family of academics. His father Julius held the Chair of Physiology at the Martin Luther University of Halle-Wittenberg, and was the Director of the Physiological Institute at the University of Halle.
While still in gymnasium in Halle, Bernstein heard the university seminar of Georg Cantor, who was a friend of Bernstein's father.
From 1896 to 1900, Bernstein studied in Munich, Halle, Berlin and Göttingen.
In the early Weimar Republic, Bernstein temporarily was Göttingen vice-chairman of the local chapter of German Democratic Party .
In 1933,
after Hitler's rise to power, Bernstein was removed from his chair, per §6 of the Nazi Law for the Restoration of the Professional Civil Service, often used against politically unpopular persons.
He received the message of his dismissal during a research/lecturing journey (started on Dec. 1st, 1932) to the United States, and he stayed there. He was a visiting professor of mathematics at Columbia University from 1933 to 1936 and a professor of biometry at New York University from 1936 to 1943. In 1942 he was elected a fellow of the American Association for the Advancement of Science. In 1948, Bernstein retired from teaching in the US, and returned to Europe.
He mainly lived in Rome and Freiburg, occasionally visiting Göttingen, where he became professor emeritus.
He died of cancer in Zurich on 3 December 1956.
Publications
(Dissertation, 1901); reprint Jan 2010,
— Corrections in Vol.29 (1920), p. 94
Notes
See also
Cantor–Bernstein theorem
Schröder–Bernstein property |
https://en.wikipedia.org/wiki/Potassium%20bromate | Potassium bromate (), is a bromate of potassium and takes the form of white crystals or powder. It is a strong oxidizing agent.
Preparation
Potassium bromate is produced when bromine is passed through a hot solution of potassium hydroxide. This first forms unstable potassium hypobromite, which quickly disproportionates into bromide and bromate:
3 2 +
Electrolysis of potassium bromide solutions will also give bromate. Both processes are analogous to those used in the production of chlorates.
Potassium bromate is readily separated from the potassium bromide present in both methods owing to its much lower solubility; when a solution containing potassium bromate and bromide is cooled to 0°C, nearly all bromate will precipitate, while nearly all of the bromide will stay in solution.
Uses in baking
Potassium bromate is typically used in the United States as a flour improver (E number E924). It acts to strengthen the dough and to allow higher rising. It is an oxidizing agent, and under the right conditions will be completely reduced to bromide in the baking process. However, if too much is added, or if the bread is not baked long enough or not at a high enough temperature, then a residual amount will remain, which may be harmful if consumed.
Potassium bromate might also be used in the production of malt barley, for which application the U.S. Food and Drug Administration (FDA) has prescribed certain safety conditions, including labeling standards for the finished malt barley product. It is a very powerful oxidizer (electrode potential similar to potassium permanganate).
Regulation
In October 2023, California Governor Gavin Newsom approved a law that banned the manufacture, sale and distribution of potassium bromate (along with three other additives). This is the first law in the U.S. to ban it, and will possible have nationwide effects.
Potassium bromate has been banned from food products in the European Union, Argentina, Brazil,
Canada, Nigeria, South Korea, |
https://en.wikipedia.org/wiki/Nothing%20by%20mouth | Nothing by mouth is a medical instruction meaning to withhold food and fluids. It is also known as nil per os (npo or NPO), a Latin phrase that translates to English as "nothing through the mouth". Variants include nil by mouth (NBM), nihil/non/nulla per os, or complete bowel rest. A liquid-only diet may also be referred to as bowel rest.
NPO is one of the abbreviations that is not used in AMA style; "nothing by mouth" is spelled out instead.
Purpose
The typical reason for NPO instructions is the prevention of aspiration pneumonia, e.g. in those who will undergo general anesthesia, or those with weak swallowing musculature, or in case of gastrointestinal bleeding, gastrointestinal blockage, or acute pancreatitis. Alcohol overdoses that result in vomiting or severe external bleeding also warrant NPO instructions for a period.
Duration
Pre-surgery NPO orders are typically between 6 and 12 hours prior to surgery, through recovery suite discharge, but may be longer if long acting medications or oral post-meds were administered. It is not uncommon for the food NPO period to be longer than that for liquid, as the American Board of Anesthesiology advises against liquid NPO periods greater than eight hours. The NPO periods for illness tend to be much longer, although exceptions are made for small scheduled amounts of water consumption if an IV drip is not in use. With sufficient IV fluids, NPO periods of several days have been utilized successfully in non-diabetic patients (although short NPO periods in diabetics are possible with IV fluids, insulin, and dextrose. Extended periods (greater than 12 hours) are still contraindicated.
The American Board of Anesthesiology recommends that patients should not eat solid food for at least 8 hours prior to a procedure, and should not drink even clear liquids for at least 2 hours prior. Clear liquid fasting includes water, juices without pulp, carbonated beverages, clear tea, and black coffee. Ingestion of water 2 hours prior to |
https://en.wikipedia.org/wiki/Bulgarian%20solitaire | In mathematics and game theory, Bulgarian solitaire is a card game that was introduced by Martin Gardner.
In the game, a pack of cards is divided into several piles. Then for each pile, remove one card; collect the removed cards together to form a new pile (piles of zero size are ignored).
If is a triangular number (that is, for some ), then it is known that Bulgarian solitaire will reach a stable configuration in which the sizes of the piles are . This state is reached in moves or fewer. If is not triangular, no stable configuration exists and a limit cycle is reached.
Random Bulgarian solitaire
In random Bulgarian solitaire or stochastic Bulgarian solitaire a pack of cards is divided into several piles. Then for each pile, either leave it intact or, with a fixed probability , remove one card; collect the removed cards together to form a new pile (piles of zero size are ignored). This is a finite irreducible Markov chain.
In 2004, Brazilian probabilist of Russian origin Serguei Popov showed that stochastic Bulgarian solitaire spends "most" of its time in a "roughly" triangular distribution. |
https://en.wikipedia.org/wiki/RSSSF | The Rec.Sport.Soccer Statistics Foundation (RSSSF) is an international organization dedicated to collecting statistics about association football. The foundation aims to build an exhaustive archive of football-related information from around the world.
History
This enterprise, according to its founders, was created in January 1994 by three regulars of the Rec.Sport.Soccer (RSS) Usenet newsgroup: Lars Aarhus, Kent Hedlundh, and Karel Stokkermans. It was originally known as the "North European Rec.Sport.Soccer Statistics Foundation", but the geographical reference was dropped as its membership from other regions grew.
The RSSSF has members and contributors from all around the world and has spawned seven spin-off projects to more closely follow the leagues of that project's home country. The spin-off projects are dedicated to Albania, Brazil, Denmark, Norway, Romania, Uruguay, Venezuela and Egypt. In November 2002, the Polish service 90minut.pl became the official branch of RSSSF Poland.
Reception
RSSSF's database has been described as the "very best" for football data.
Rec.Sport.Soccer Player of the Year
Since 1992 a vote for the Best Footballer in the World among the readers of the rec.sport.soccer newsgroup. It was held yearly until 2005, when it was discontinued. The voting works as follows: each voter chooses five players, at most two of the same nationality, in order; these obtain five to one points. The nationality restriction was dropped for the 2003 vote, in which voting was restricted to 173 pre-selected players.
Wins by player
Wins by country
Wins by club |
https://en.wikipedia.org/wiki/Alphabet%20to%20E-mail | Alphabet to E-mail: How Written English Evolved and Where It's Heading () is a book by linguist Dr. Naomi Baron, a professor of linguistics at American University, Washington, D.C. It was first published in 2000, published by Routledge Press.
In it, Baron explores the history of the English language in written form, and considers how it has evolved through its history, ending with an evaluation of the state of the English language today, and how the Internet and the use of email and text messaging has affected it.
Baron considered that email did not have an inherent writing style, and believed it was evolving to resemble speech. She also expressed her disappointment with the effect of electronic means of communication upon the written word.
Baron noted that 25-years of research revealed that: |
https://en.wikipedia.org/wiki/Stamped%20concrete | Stamped concrete is concrete that has been imprinted, or that is patterned, textured, or embossed to resemble brick, slate, flagstone, stone, tile, wood, or various other patterns and textures. The practice of stamping concrete for various purposes began with the ancient Romans. In the nineteenth and twentieth centuries, concrete was sometimes stamped with contractor names and years during public works projects, but by the late twentieth century the term "stamped concrete" came to refer primarily to decorative concrete produced with special modern techniques for use in patios, sidewalks, driveways, pool decks, and interior flooring.
History
The ancient Romans used basic concrete stamping techniques, as evidenced in well-known structures such as the Pantheon. In the late nineteenth and early twentieth centuries, concrete companies who received government bids for public works projects sometimes used concrete stamps featuring the company name and sometimes the year in which the concrete was poured, creating a visible historical record of when certain sidewalks were made.
Concrete manufacturers started experimenting with modern decorative concrete techniques as early as the 1890s. In the 1950s, Brad Bowman—considered the "father" of modern concrete stamping—began developing and patenting new techniques for producing concrete that resembled non-concrete materials, such as flagstone and wood. He used wooden platform stamps that could imprint multiple pieces of concrete at once. Later, platform stamps would be made of sheet metal or aluminium. In 1956, Bill Stegmeier of the Stegmeier Company, discovered that a color powder used to impart an antiquing effect to concrete also had the property of preventing stamps from sticking to concrete, which opened up new possibilities.
By the 1970s the demand for stamped concrete grew, and the material became a common component in building projects. In the late 1970s, manufacturer Jon Nasvik developed lightweight and durable ureth |
https://en.wikipedia.org/wiki/Boyer%E2%80%93Lindquist%20coordinates | In the mathematical description of general relativity, the Boyer–Lindquist coordinates are a generalization of the coordinates used for the metric of a Schwarzschild black hole that can be used to express the metric of a Kerr black hole.
The Hamiltonian test for particle motion in Kerr spacetime is separable in Boyer–Lindquist coordinates. Using Hamilton–Jacobi theory one can derive a fourth constant of the motion known as Carter's constant.
The 1967 paper introducing Boyer–Lindquist coordinates was a posthumous publication for Robert H. Boyer, who was killed in the 1966 University of Texas tower shooting.
Line element
The line element for a black hole with a total mass equivalent , angular momentum , and charge in Boyer–Lindquist coordinates and geometrized units () is
where
called the discriminant,
and
called the Kerr parameter.
Note that in geometrized units , , and all have units of length. This line element describes the Kerr–Newman metric. Here, is to be interpreted as the mass of the black hole, as seen by an observer at infinity, is interpreted as the angular momentum, and the electric charge. These are all meant to be constant parameters, held fixed. The name of the discriminant arises because it appears as the discriminant of the quadratic equation bounding the time-like motion of particles orbiting the black hole, i.e. defining the ergosphere.
The coordinate transformation from Boyer–Lindquist coordinates , , to Cartesian coordinates , , is given (for ) by:
Vierbein
The vierbein one-forms can be read off directly from the line element:
so that the line element is given by
where is the flat-space Minkowski metric.
Spin connection
The torsion-free spin connection is defined by
The contorsion tensor gives the difference between a connection with torsion, and a corresponding connection without torsion. By convention, Riemann manifolds are always specified with torsion-free geometries; torsion is often used to specify equivalent, flat ge |
https://en.wikipedia.org/wiki/External%20storage | In computing, external storage refers to non-volatile (secondary) data storage outside a computer's own internal hardware, and thus can be readily disconnected and accessed elsewhere. Such storage devices may refer to removable media (e.g. punched paper, magnetic tape, floppy disk and optical disc), compact flash drives (USB flash drive and memory card), portable storage devices (external solid state drive and enclosured hard disk drive), or network-attached storage. Web-based cloud storage is the latest technology for external storage.
History
Today the term external storage most commonly applies to those storage devices external to a personal computer. The terms refer to any storage external to the computer.
Storage as distinct from memory in the early days of computing was always external to the computer as for example in the punched card devices and media. Today storage devices may be internal or external to a computer system.
In the 1950s, introduction of magnetic tapes and hard disk drives allowed for mass external storage of information, which played the key part of the computer revolution. Initially all external storage, tape and hard disk drives are today available as both internal and external storage.
In the 1964 removable disk media was introduced by the IBM 2310 disk drive with its 2315 cartridge used in IBM 1800 and IBM 1130 computers. Magnetic disk media is today not removable; however disk devices and media such as optical disc drives and optical discs are available both as internal storage and external storage.
Earlier adoption of external storage
As a consequence of rapid development of electronic computers, capability for integration of existing input, output, and storage devices was a determinant factor in their adoption. IBM 650 was a first mass-produced electronic computer that encompassed wide range of existing in technologies for input-output and memory devices, and it also included tape-to-card and card-to-tape conversion units. Earl |
https://en.wikipedia.org/wiki/Calcium%20lactate | Calcium lactate is a white crystalline salt with formula , consisting of two lactate anions (CHOH) for each calcium cation . It forms several hydrates, the most common being the pentahydrate ·5.
Calcium lactate is used in medicine, mainly to treat calcium deficiencies; and as a food additive with E number of E327. Some cheese crystals consist of calcium lactate.
Properties
The lactate ion is chiral, with two enantiomers, D (−,R) and L (+,S). The L isomer is the one normally synthesized and metabolized by living organisms, but some bacteria can produce the D form or convert the L to D. Thus calcium lactate also has D and L isomers, where all anions are of the same type.
Some synthesis processes yield a mixture of the two in equal parts, resulting in the DL (racemic) salt. Both the L and the DL forms occur as crystals on the surface of aging Cheddar cheese.
The solubility of calcium L-lactate in water increases significantly in presence of d-gluconate ions, from 6.7 g/dl) at 25 °C to 9.74 g/dl or more. Paradoxically, while the solubility of calcium L-lactate increases with temperature from 10 °C (4.8 g/dl) to 30 °C (8.5 g/dl), the concentration of free ions decreases by almost one half. This is explained as the lactate and calcium ions becoming less hydrated and forming a complex .
The DL (racemic) form of the salt is much less soluble in water than the pure L or D isomers, so that a solution that contains as little as 25% of the D form will deposit racemic DL-lactate crystals instead of L-lactate.
The pentahydrate loses water in a dry atmosphere between 35 and 135 °C, being reduced to the anhydrous form and losing its crystalline character. The process is reversed at 25 °C and 75% relative humidity.
Preparation
Calcium lactate can be prepared by the reaction of lactic acid with calcium carbonate or calcium hydroxide.
Since the 19th century, the salt has been obtained industrially by fermentation of carbohydrates in the presence of calcium mineral sourc |
https://en.wikipedia.org/wiki/Kuromasu | , abbreviated or , is a binary-determination logic puzzle published by Nikoli. , one book consisting entirely of puzzles has been published by Nikoli.
Rules
is played on a rectangular grid. Some of these cells have numbers in them. Each cell may be either black or white. The object is to determine what type each cell is.
The following rules determine which cells are which:
Each number on the board represents the number of white cells that can be seen from that cell, including itself. A cell can be seen from another cell if both cells are within the same row or column, and there are no black cells between them in that row or column.
Numbered cells must not be black.
No two black cells must be horizontally or vertically adjacent.
All the white cells must be connected horizontally or vertically.
Solution methods
A number of methods of solving puzzles exist.
Any cell with a number in it must be white; this is very important. For example, a 2 cell with another numbered cell next to it would be visible from the 2 cell, and no other cells can be visible from the 2 cell. Therefore, all neighbouring cells to the 2 cell must be black. The cell beyond the other numbered cell must also be black. This is one method of starting some puzzles.
Another method of beginning some puzzles starts from a 2 cell and another numbered cell or white cell in the same row or column, with just one space between them. The cell in the middle must be black, as if it were white, the 2 cell would be able to see at least 3 cells.
If the number inside a cell is equal to the maximum number of cells it could possibly see, then all those cells must be white in order for that maximum to be possible. For example, in a 7×7 puzzle, the maximum number that can be had in any cell is 13 (the cell itself, plus six others in the row, plus six other in the column). If a 13 appears in a cell of a 7×7 puzzle, all cells in the same row or column as the 13 must be white. This is often represented by p |
https://en.wikipedia.org/wiki/Pityriasis%20lichenoides%20chronica | Pityriasis lichenoides chronica is an uncommon, idiopathic, acquired dermatosis, characterized by evolving groups of erythematous, scaly papules that may persist for months.
Symptoms and signs
Although other forms of the disease occur at younger ages, some individuals start having long term symptoms at thirty years of age. This disease also affects adolescents and young adults. This also affects the immune system which therefore results in rashes. The symptoms rarely affect the face or scalp, but occurs at other sites of the body. The duration may last for months or even several years. For instance, new crops of lesions appear every few weeks.
Causes
Pityriasis lichenoides chronica is probably caused by a hypersensitivity reaction to infectious agents such as the Epstein–Barr virus. Other infectious agents include the adenovirus and Parvovirus B19.
Treatment
There is no standard treatment for pityriasis lichenoides chronica. Treatments may include ultraviolet phototherapy, sun exposure, oral antibiotics, and corticosteroid creams and ointments to treat rash and itching. One study identified the enzyme bromelain as an effective therapeutic option for pityriasis lichenoides chronica.
See also
Cutaneous T-cell lymphoma
Parapsoriasis
Pityriasis lichenoides
List of cutaneous conditions |
https://en.wikipedia.org/wiki/Compal%20Electronics | Compal Electronics () is a Taiwanese original design manufacturer (ODM), handling the production of notebook computers, monitors, tablets and televisions for a variety of clients around the world, including Apple Inc., Alphabet Inc., Acer, Lenovo, Dell, Toshiba, Hewlett-Packard and Fujitsu. It also licenses brands of its clients.
It is the second-largest contract laptop manufacturer in the world behind Quanta Computer, and shipped over 48 million notebooks in 2010.
Overview
The company is known for producing selected models for Dell (Alienware included), Hewlett-Packard, Compaq, and Toshiba. Compal has designed and built laptops for all major brands and custom builders for over 22 years. The company is listed in Taiwan Stock Exchange. As of 2017, revenues were US$24 billion, with a total workforce of 64,000. The company's headquarters is in Taipei, Taiwan, with offices in mainland China, South Korea, the United Kingdom, and the United States. Compal's main production facility is in Kunshan, China.
Compal is the second largest notebook manufacturer in the world after Quanta Computers, also based in Taiwan.
History
Compal was founded in June 1984 as a computer peripherals supplier. It went public in April 1990.
In September 2011, Compal announced it would form a joint venture with Lenovo to make laptops in China. The venture was expected to start producing laptops by the end of 2012.
In January 2015, Toshiba announced that due to intense price competition, it will stop selling televisions in the USA and will instead license the Toshiba TV brand to Compal.
In September 2018, it was revealed that due to overwhelming demand for the Apple Watch, Compal was brought on as a second contract manufacturer to produce the Apple Watch Series 4.
CCI
Compal subsidiary Compal Communications (華寶通訊, CCI) is a major manufacturer of mobile phones. The phones are produced on an ODM basis, i.e., the handsets are sold through other brands. In 2006, CCI produced 68.8 million hands |
https://en.wikipedia.org/wiki/Bhutanese%20red%20rice | Bhutanese red rice is a medium-grain rice grown in the Kingdom of Bhutan in the eastern Himalayas. It is the staple rice of the Bhutanese people.
Bhutanese red rice is a red japonica rice. It is semi-milled—some of the reddish bran is left on the rice. Because of this, it cooks somewhat faster than an unmilled brown rice. When cooked, the rice is pale pink, soft and slightly sticky.
This rice became available in the United States in the mid-1990s when Lotus Foods began importing it, and it is currently the only agricultural product imported from Bhutan.
See also
Red rice |
https://en.wikipedia.org/wiki/Minnesota%20Center%20for%20Twin%20and%20Family%20Research | The Minnesota Center for Twin and Family Research (or MCTFR) is a series of behavioral genetic longitudinal studies of families with twin or adoptive offspring conducted by researchers at the University of Minnesota. It seeks to identify and characterize the genetic and environmental influences on the development of psychological traits.
Principal investigators include Matt McGue, William Iacono, and Kevin Haroian.
Cohorts
The primary cohorts of participants include the Minnesota Twin Family Study, Sibling Interaction and Behavior Study, Minnesota Twin Registry, and a variety of other cohorts of participants.
Minnesota Twin Family Study
MTFS is a twin study established in June 1989 with 1300 same-gendered twin pairs age 11 or 17, with an additional cohort of 500 such pairs recruited around 2004. Twins were born between 1972 and 2000. All twins born in Minnesota at that time were eligible to participate using birth registry data. Both identical and fraternal twins share certain aspects of their environment. This allows researchers to estimate the relative impact of environmental and genetic influences on phenotypes. The focus of the MTFS is on behavioral phenotypes, such as academic outcomes, cognitive abilities, personality, and interests; family and social relationships; mental and physical health; physiological measurements. The assessment wave structure and protocol are similar to the Sibling Interaction and Behavior Study (below), allowing the use of complementary twin and adoption designs to address behavioral genetic questions.
Minnesota Twin Registry
The Minnesota Twin Registry was established in 1983. Its original goal was to establish a registry of all twins born in Minnesota from 1936 to 1955 to be used for psychological research. Recently, it has added twins born between 1961 and 1964. It primarily conducts personality and interests tests with its 8,000+ twin pairs and family members via mail. From this project, it was able to confirm that twins |
https://en.wikipedia.org/wiki/Percy%20Alexander%20MacMahon | Percy Alexander MacMahon (26 September 1854 – 25 December 1929) was a mathematician, especially noted in connection with the partitions of numbers and enumerative combinatorics.
Early life
Percy MacMahon was born in Malta to a British military family. His father was a colonel at the time, retired in the rank of the brigadier.
MacMahon attended the Proprietary School in Cheltenham. At the age of 14 he won a Junior Scholarship to Cheltenham College, which he attended as a day boy from 10 February 1868 until December 1870. At the age of 16 MacMahon was admitted to the Royal Military Academy, Woolwich and passed out after two years.
Military career
On 12 March 1873, MacMahon was posted to Madras, India, with the 1st Battery 5th
Brigade, with the temporary rank of lieutenant. The Army List showed that in October 1873 he was posted to the 8th Brigade in Lucknow. MacMahon's final posting was to the No. 1 Mountain Battery with the Punjab Frontier Force at Kohat on the North West Frontier. He was appointed Second Subaltern on 26 January and joined the Battery on 25 February 1877. In the Historical Record of the No. 1 (Kohat) Mountain Battery, Punjab Frontier Force it is recorded that he was sent on sick leave to Muree (or Maree), a town north of Kohat on the banks of the Indus river, on 9 August 1877. On 22 December 1877 he started 18 months leave on a medical certificate granted under GGO number 1144. The nature of his illness is unknown.
This period of sick leave was one of the most significant occurrences in MacMahon's life. Had he remained in India he would undoubtedly have been caught up in Roberts's War against the Afghans. In early 1878 MacMahon returned to England and the sequence of events began which led to him becoming a mathematician rather than a soldier. The Army List records a transfer to the 3rd Brigade in Newbridge at the beginning of 1878, and then shows MacMahon as 'supernumerary' from May 1878 until March 1879.
In January 1879 MacMahon was posted |
https://en.wikipedia.org/wiki/Peter%20Whittle%20%28mathematician%29 | Peter Whittle (27 February 1927 – 10 August 2021) was a mathematician and statistician from New Zealand, working in the fields of stochastic nets, optimal control, time series analysis, stochastic optimisation and stochastic dynamics. From 1967 to 1994, he was the Churchill Professor of Mathematics for Operational Research at the University of Cambridge.
Career
Whittle was born in Wellington. He graduated from the University of New Zealand in 1947 with a BSc in mathematics and physics and in 1948 with an MSc in mathematics.
He then moved to Uppsala, Sweden in 1950 to study for his PhD with Herman Wold (at Uppsala University). His thesis, Hypothesis Testing in Time Series, generalised Wold's autoregressive representation theorem for univariate stationary processes to multivariate processes. Whittle's thesis was published in 1951. A synopsis of Whittle's thesis also appeared as an appendix to the second edition of Wold's book on time-series analysis. Whittle remained in Uppsala at the Statistics Institute as a docent until 1953, when he returned to New Zealand.
In New Zealand, Whittle worked at the Department of Scientific and Industrial Research (DSIR) in the Applied Mathematics Laboratory (later named the Applied Mathematics Division).
In 1959 Whittle was appointed to a lectureship in Cambridge University. Whittle was appointed Professor of Mathematical statistics at the University of Manchester in 1961. After six years in Manchester, Whittle returned to Cambridge as the Churchill Professor of Mathematics for Operational Research, a post he held until his retirement in 1994. From 1973, he was also Director of the Statistical Laboratory, University of Cambridge.
He was a fellow of Churchill College, Cambridge. He died in Cambridge, England.
Recognition
Whittle was elected a Fellow of the Royal Society in 1978, and an Honorary Fellow of the Royal Society of New Zealand in 1981. The Royal Society awarded him their Sylvester Medal in 1994 in recognition of his "m |
https://en.wikipedia.org/wiki/Applied%20Physics%20Laboratory | The Johns Hopkins University Applied Physics Laboratory (Applied Physics Laboratory, or APL) is a not-for-profit university-affiliated research center (UARC) in Howard County, Maryland. It is affiliated with Johns Hopkins University and employs 8,500 people as of 2023. APL is the nation's largest UARC.
The lab serves as a technical resource for the Department of Defense, NASA, and other government agencies. APL has developed numerous systems and technologies in the areas of air and missile defense, surface and undersea naval warfare, computer security, and space science and spacecraft construction. While APL provides research and engineering services to the government, it is not a traditional defense contractor, as it is a UARC and a division of Johns Hopkins University. APL is a scientific and engineering research and development division, rather than an academic division, of Johns Hopkins.
Hopkins' Whiting School of Engineering offers part-time graduate programs for Lab staff members through its Engineering for Professionals program. Courses are taught at seven locations in the Baltimore-Washington Metropolitan Area, including the APL Education Center.
History
APL was created in 1942 during World War II under the Office of Scientific Research and Development's Section T as part of the Government's effort to mobilize the nation's science and engineering expertise within its universities. Its founding director was Merle Anthony Tuve, who led Section T throughout the war. Section T was created on August 17, 1940. According to the official history of the Office of Scientific Research and Development, Scientists Against Time, APL was the name of Section T's main laboratory from 1942 onward, not the name of the organization overall. Section T's Applied Physics Laboratory succeeded in developing the variable-time proximity fuze that played a significant role in the Allied victory. In response to the fuze's success, the APL created the MK 57 gun director in 1944. Pleas |
https://en.wikipedia.org/wiki/Stellated%20octahedron | The stellated octahedron is the only stellation of the octahedron. It is also called the stella octangula (Latin for "eight-pointed star"), a name given to it by Johannes Kepler in 1609, though it was known to earlier geometers. It was depicted in Pacioli's De Divina Proportione, 1509.
It is the simplest of five regular polyhedral compounds, and the only regular compound of two tetrahedra. It is also the least dense of the regular polyhedral compounds, having a density of 2.
It can be seen as a 3D extension of the hexagram: the hexagram is a two-dimensional shape formed from two overlapping equilateral triangles, centrally symmetric to each other, and in the same way the stellated octahedron can be formed from two centrally symmetric overlapping tetrahedra. This can be generalized to any desired amount of higher dimensions; the four-dimensional equivalent construction is the compound of two 5-cells. It can also be seen as one of the stages in the construction of a 3D Koch snowflake, a fractal shape formed by repeated attachment of smaller tetrahedra to each triangular face of a larger figure. The first stage of the construction of the Koch Snowflake is a single central tetrahedron, and the second stage, formed by adding four smaller tetrahedra to the faces of the central tetrahedron, is the stellated octahedron.
Construction
The Cartesian coordinates of the stellated octahedron are as follows:
(±1/2, ±1/2, 0)
(0, 0, ±1/√2)
(±1, 0, ±1/√2)
(0, ±1, ±1/√2)
The stellated octahedron can be constructed in several ways:
It is a stellation of the regular octahedron, sharing the same face planes. (See Wenninger model W19.)
It is also a regular polyhedron compound, when constructed as the union of two regular tetrahedra (a regular tetrahedron and its dual tetrahedron).
It can be obtained as an augmentation of the regular octahedron, by adding tetrahedral pyramids on each face. In this construction it has the same topology as the convex Catalan solid, the triakis octahed |
https://en.wikipedia.org/wiki/TOTEM%20experiment | The TOTEM experiment (TOTal Elastic and diffractive cross section Measurement) is one of the nine detector experiments at CERN's Large Hadron Collider. The other eight are: ATLAS, ALICE, CMS, LHCb, LHCf, MoEDAL, FASER and SND@LHC. It shares an interaction point with CMS. The detector aims at measurement of total cross section, elastic scattering, and diffraction processes. The primary instrument of the detector is referred to as a Roman pot. In December 2020, the D0 and TOTEM Collaborations made public the odderon discovery based on a purely data driven approach in a CERN and Fermilab approved preprint that was later published in Physical Review Letters. In this experimental observation, the TOTEM proton-proton data in the region of the diffractive minimum and maximum was extrapolated from 13, 8, 7 and 2.76 TeV to 1.96 TeV and compared this to D0 data at 1.96 TeV in the same t-range giving an odderon significance of 3.4 σ. When combined with TOTEM experimental data at 13 TeV at small scattering angles providing an odderon significance of 3.4 - 4.6 σ, the combination resulted in an odderon significance of at least 5.2 σ.
See also
CERN: European Organization for Nuclear Research
Large Hadron Collider |
https://en.wikipedia.org/wiki/Xain%27d%20Sleena | is a two genre platformer and side-scrolling arcade video game produced by Technos in 1986. It was licensed for release outside of Japan by Taito. In the USA, the game was published by Memetron, and the game was renamed to Solar Warrior. The European home computer ports renamed the game to Soldier of Light.
Gameplay
The main character, Xain, is a galactic bounty-hunter who must defeat evil forces who oppress five different planets. The player can select any order to play the various planets, so, there is no 'official' sequence of play (For the U.S. version, this game was released as 'Solar Warrior'. This version goes through a set sequence instead of having to choose planets).
Each planet is played with right horizontal and vertical scrolling, shooting enemies and dodging natural hazards. Xain can crouch, double crouch (prone), jump and double jump. In some of the planets the player will need to kill a sub-boss to resume. Certain enemies carry a powerup which changes the default laser gun into a different weapon. The different weapons which are cycled through powerups include a laser-grenade gun, a 2-way gun, a spreadfire gun and a strong bullet gun with their own respective damage and directional firing capabilities.
At the end of the planet, the player goes into battle with a boss. Once defeated, the player plants a bomb into the boss' base and has ten seconds to escape in a starship.
The next half of the planet stage is an interlude stage during which the player must battle through waves of enemy ships while heading to the next planet. After three planets there is a battle through an asteroid field and against a giant mothership.
When all five planets are liberated, the player will play the longer final stage on a gigantic metallic fortress, facing the bosses previously met on each of the five planets. Fighting bosses in this stage is optional. Halfway through the stage the player plants a bomb on the fortress core and has 60 seconds to reach the exit hanga |
https://en.wikipedia.org/wiki/Degree%20of%20ionization | The degree of ionization (also known as ionization yield in the literature) refers to the proportion of neutral particles, such as those in a gas or aqueous solution, that are ionized. For electrolytes, it could be understood as a capacity of acid/base to ionize itself. A low degree of ionization is sometimes called partially ionized (also weakly ionized), and a high degree of ionization as fully ionized. However, fully ionized can also mean that an ion has no electrons left.
Ionization refers to the process whereby an atom or molecule loses one or several electrons from its atomic orbital, or conversely gains an additional one, from an incoming free electron (electron attachment). In both cases, the atom or molecule ceases to be a neutral particle and becomes a charge carrier. If the species has lost one or several electrons, it becomes positively charged and is called a positive ion, or cation. On the contrary, if the species has gained one or several additional electrons, it becomes negatively charged and is called a negative ion, or anion. Individual free electrons and ions in a plasma have very short lives typically inferior to the microsecond, as ionization and recombination, excitation and relaxation are collective continuous processes.
Chemistry usage
The degree of dissociation α (also known as degree of ionization), is a way of representing the strength of an acid. It is defined as the ratio of the number of ionized molecules and the number of molecules dissolved in water. It can be represented as a decimal number or as a percentage. One can classify strong acids as those having ionization degrees above 30%, weak acids as those with α below 30%, and the rest as moderate acids, at a specified molar concentration.
Physics usage
In plasma, the degree of ionization refers to the proportion of neutral particles that are ionized:
where is the ion density and the neutral density (in particles per cubic meter). It is a dimensionless number, sometimes expres |
https://en.wikipedia.org/wiki/ATCC%20%28company%29 | ATCC or the American Type Culture Collection is a nonprofit organization which collects, stores, and distributes standard reference microorganisms, cell lines and other materials for research and development. Established in 1925 to serve as a national center for depositing and distributing microbiological specimens, ATCC has since grown to distribute in over 150 countries. It is now the largest general culture collection in the world.
Products and collections
ATCC's collections include a wide range of biological materials for research, including cell lines, microorganisms and bioproducts. The organization holds a collection of more than 3,000 human and animal cell lines and an additional 1,200 hybridomas. ATCC's microorganism collection includes a collection of more than 18,000 strains of bacteria, as well as 3,000 different types of animal viruses and 1,000 plant viruses. In addition, ATCC maintains collections of protozoans, yeasts and fungi with over 7,500 yeast and fungus species and 1,000 strains of protists.
Services
In addition to serving as a biorepository and distributor, ATCC provides specialized services as a biological resource center. Individuals and groups can employ a safe deposit service for their own cell cultures, providing a secure back-up for valuable biomaterials if required. ATCC also is able to retain secure samples of patented materials and distribute them according to instructions and approval of the patent holder. ATCC also provides biological repository management services to institutions, agencies and companies wishing to outsource the handling of their own culture collections. ATCC also manages BEI Resources, who provides reagents, tools and information needed in research on microbes.
ATCC also serves to set standards for biological reagent and assay quality. These standards are used by the U.S. Food and Drug Administration and the U.S. Department of Agriculture, as well as organizations such as AOAC International, the Clinical and |
https://en.wikipedia.org/wiki/PCI%20eXtensions%20for%20Instrumentation | PCI eXtensions for Instrumentation (PXI) is one of several modular electronic instrumentation platforms in current use. These platforms are used as a basis for building electronic test equipment, automation systems, and modular laboratory instruments. PXI is based on industry-standard computer buses and permits flexibility in building equipment. Often, modules are fitted with custom software to manage the system.
Overview
PXI is designed for measurement and automation applications that require high-performance and a rugged industrial form-factor. With PXI, one can select the modules from a number of vendors and integrate them into a single PXI system, over 1150 module types available in 2006. A typical 3U PXI module measures approximately (4x6") in size, and a typical 8-slot PXI chassis is 4U high and half rack width, full width chassis contain up to 18 PXI slots.
PXI uses PCI-based technology and an industry standard governed by the PXI Systems Alliance (PXISA) to ensure standards compliance and system interoperability. There are PXI modules available for almost every conceivable test, measurement, and automation application, from the ubiquitous switching modules and DMMs, to high-performance microwave vector signal generation and analysis. There are also companies specializing in writing software for PXI modules, as well as companies providing PXI hardware-software integration services.
PXI is based on CompactPCI, and it offers all of the benefits of the PCI architecture including performance, industry adoption, COTS technology. PXI adds a rugged CompactPCI mechanical form-factor, an industry consortium that defines hardware, electrical, software, power and cooling requirements. Then PXI adds integrated timing and synchronization that is used to route synchronization clocks, and triggers internally. PXI is a future-proof technology, and is designed to be simply and quickly reprogrammed as test, measurement, and automation requirements change.
Most PXI instru |
https://en.wikipedia.org/wiki/Crystal%20oven | A crystal oven is a temperature-controlled chamber used to maintain the quartz crystal in electronic crystal oscillators at a constant temperature, in order to prevent changes in the frequency due to variations in ambient temperature. An oscillator of this type is known as an oven-controlled crystal oscillator (OCXO, where "XO" is an old abbreviation for "crystal oscillator".) This type of oscillator achieves the highest frequency stability possible with a crystal. They are typically used to control the frequency of radio transmitters, cellular base stations, military communications equipment, and for precision frequency measurement.
Description
Quartz crystals are widely used in electronic oscillators to precisely control the frequency produced. The frequency at which a quartz crystal resonator vibrates depends on its physical dimensions. A change in temperature causes the quartz to expand or contract due to thermal expansion, changing the frequency of the signal produced by the oscillator. Although quartz has a very low coefficient of thermal expansion, temperature changes are still the major cause of frequency variation in crystal oscillators.
The oven is a thermally-insulated enclosure containing the crystal and one or more electrical heating elements. Since other electronic components in the circuit are also vulnerable to temperature drift, usually the entire oscillator circuit is enclosed in the oven. A thermistor temperature sensor in a closed-loop control circuit is used to control the power to the heater and ensure that the oven is maintained at the precise temperature desired. Because the oven operates above ambient temperature, the oscillator usually requires a warm-up period after power has been applied to reach its operating temperature. During this warm-up period, the frequency will not have the full rated stability.
The temperature selected for the oven is that at which the slope of the crystal's frequency vs. temperature curve is zero, further i |
https://en.wikipedia.org/wiki/TO-220 | The TO-220 is a style of electronic package used for high-powered, through-hole components with pin spacing. The "TO" designation stands for "transistor outline". TO-220 packages have three leads. Similar packages with two, four, five or seven leads are also manufactured. A notable characteristic is a metal tab with a hole, used to mount the case to a heatsink, allowing the component to dissipate more heat than one constructed in a TO-92 case. Common TO-220-packaged components include discrete semiconductors such as transistors and silicon-controlled rectifiers, as well as integrated circuits.
Typical applications
The TO-220 package is a "power package" intended for power semiconductors and an example of a through-hole design rather than a surface-mount technology type of package. TO-220 packages can be mounted to a heat sink to dissipate several watts of waste heat. On a so-called "infinite heat sink", this can be 50 W or more. The top of the package has a metal tab with a hole used to mount the component to a heat sink. Thermal compound is often applied between package and heatsink to further improve heat transfer.
The metal tab is often connected electrically to the internal circuitry. This does not normally pose a problem when using isolated heatsinks, but an electrically-insulating pad or sheet may be required to electrically isolate the component from the heatsink if the heatsink is electrically conductive, grounded or otherwise non-isolated. Many materials may be used to electrically isolate the TO-220 package, some of which have the added benefit of high thermal conductivity.
In applications that require a heatsink, damage or destruction of the TO-220 device due to overheating may occur if the heatsink is dislodged during operation.
A heatsinked TO-220 package dissipating 1 W of heat will have an internal (junction) temperature typically 2 to 5 °C higher than the package's temperature (due to the thermal resistance between the junction and the meta |
https://en.wikipedia.org/wiki/GOST | GOST () refers to a set of international technical standards maintained by the Euro-Asian Council for Standardization, Metrology and Certification (EASC), a regional standards organization operating under the auspices of the Commonwealth of Independent States (CIS).
All sorts of regulated standards are included, with examples ranging from charting rules for design documentation to recipes and nutritional facts of Soviet-era brand names. The latter have become generic, but may only be sold under the label if the technical standard is followed, or renamed if they are reformulated.
History
GOST standards were originally developed by the government of the Soviet Union as part of its national standardization strategy. The word GOST (Russian: ) is an acronym for gosudarstvennyy standart (Russian: ), which means government standard.
The history of national standards in the USSR can be traced back to 1925, when a government agency, later named Gosstandart, was established and put in charge of writing, updating, publishing, and disseminating the standards. After World War II, the national standardization program went through a major transformation. The first GOST standard, GOST 1 State Standardization System, was published in 1968.
Present
After the disintegration of the USSR, the GOST standards acquired a new status of the regional standards. They are now administered by the Euro-Asian Council for Standardization, Metrology and Certification (EASC), a standards organization chartered by the Commonwealth of Independent States.
At present, the collection of GOST standards includes over 20,000 titles used extensively in conformity assessment activities in 12 countries. Serving as the regulatory basis for government and private-sector certification programs throughout the Commonwealth of Independent States (CIS), the GOST standards cover energy, oil and gas, environmental protection, construction, transportation, telecommunications, mining, food processing, and other in |
https://en.wikipedia.org/wiki/Magnetotaxis | Magnetotaxis is a process implemented by a diverse group of Gram-negative bacteria that involves orienting and coordinating movement in response to Earth's magnetic field. This process is mainly carried out by microaerophilic and anaerobic bacteria found in aquatic environments such as salt marshes, seawater, and freshwater lakes. By sensing the magnetic field, the bacteria are able to orient themselves towards environments with more favorable oxygen concentrations. This orientation towards more favorable oxygen concentrations allows the bacteria to reach these environments faster as opposed to random movement through Brownian motion.
Overview
Magnetic bacteria (e.g. Magnetospirillum magnetotacticum) contain internal structures known as magnetosomes which are responsible for the process of magnetotaxis. After orienting to the magnetic field using the magnetosomes, the bacteria use flagella to swim along the magnetic field, towards the more favorable environment. Magnetotaxis has no impact on the average speed of the bacteria. However, magnetotaxis allows bacteria to guide their otherwise random movement. This process is similar in practice to aerotaxis, but governed by magnetic fields instead of oxygen concentrations. Magnetotaxis and aerotaxis often function together, as bacteria can use both magnetotactic and aerotactic systems to find proper oxygen concentrations. This is referred to as magneto-aerotaxis. By orienting towards the Earth's poles, marine bacteria are able to direct their movement downwards, towards the anaerobic/micro aerobic sediments. This allows bacteria to change metabolic environments, which can enable chemical cycles.
Magnetosomes
Magnetosomes contain crystals - often magnetite (Fe3O4). Some extremophile bacteria from sulfurous environments have been isolated with greigite (an iron-sulfide compound Fe3S4). Some magnetotactic bacteria also contain pyrite (FeS2) crystals, possibly as a transformation product of greigite. These crystals are c |
https://en.wikipedia.org/wiki/Bernd%20das%20Brot | Bernd das Brot () is a puppet character, star mascot and pop cultural icon of the German children's television channel KiKA, currently featured in the programs Bernd das Brot, Bravo Bernd, and the KiKA late night loop programme. He is primarily characterised by his chronic depression.
Role on KiKA
Bernd is a depressed and curmudgeonly loaf of pullman bread speaking in a deep, gloomy baritone. He is small, rectangular and golden brown with hands directly attached to his body, rings around his eyes and a thin-lipped mouth. According to himself, he belongs to the species homo brotus depressivus. His favourite activities include staring at his south wall at home, learning the pattern of his woodchip wallpaper by heart, reading his favourite magazine The Desert and You, and enlarging his collection of the most boring railway tracks on video. Bernd sympathizes firstly with himself, and is bad-tempered and fatalistic.
His favorite expression is Mist., used in much the same way as the English "crap". His other catchphrases are: "I would like to be left alone," "I would like to leave this show," and "My life is hell."
According to his in-universe backstory, the short-armed bread character made his first appearance as part of an advertising campaign for a bakery chain. When the campaign turned out unsuccessful, Bernd was forced to apply for job at the KiKA (more specifically, the MDR member of the ARD) which is also the reason for his permanent scowl. Bernd himself does not want to appear on television and thinks it is a "dirty business".
Bernd interacts with two co-main characters. One is the chatty Chili das Schaf ("Chili the sheep"), a female, yellow sheep with flaming red hair. Chili, the show's Gastgeberin (hostess), is a Stuntschaf (stuntsheep) who finds it exciting to have close calls with accidents. The other main character is the show's technical expert, the always pleasant Briegel der Busch (Briegel the Bush), a green, bespectacled bush with flowers and leaves |
https://en.wikipedia.org/wiki/Pierre%20Samuel | Pierre Samuel (12 September 1921 – 23 August 2009) was a French mathematician, known for his work in commutative algebra and its applications to algebraic geometry. The two-volume work Commutative Algebra that he wrote with Oscar Zariski is a classic. Other books of his covered projective geometry and algebraic number theory.
Early life and education
Samuel studied at the Lycée Janson-de-Sailly in Paris before attending the École Normale Supérieure where he studied for his Agrégé de mathematique. He received his Master of Arts and then a Ph.D. from Princeton University in 1947, under the supervision of Oscar Zariski, with a thesis "Ultrafilters and Compactification of Uniform Spaces".
Career
Samuel ran a Paris seminar during the 1960s, and became Professeur émérite at the Université Paris-Sud (Orsay). His lectures on unique factorization domains published by the Tata Institute of Fundamental Research played a significant role in computing the Picard group of a Zariski surface via the work of Jeffrey Lang and collaborators. The method was inspired by earlier work of Nathan Jacobson and Pierre Cartier another outstanding member of the Bourbaki group. Nicholas Katz related this to the concept of p-curvature of a connection introduced by Alexander Grothendieck.
He was a member of the Bourbaki group, and filmed some of their meetings. A French television documentary on Bourbaki broadcast some of this footage in 2000.
Samuel was also active in issues of social justice, including concerns about environmental degradation (where he was influenced by Grothendieck), and arms control. He died in Paris in August 2009.
His doctoral students include Lucien Szpiro and Daniel Lazard.
Awards and honors
In 1958 he was an invited speaker (Relations d'équivalence en géométrie algébrique) at the ICM in Edinburgh. In 1969 he won the Lester R. Ford Award.
Works
with Oscar Zariski:
with Oscar Zariski:
Anneaux factoriels, Publicaçoes da Sociedade de Matematica de São Paulo |
https://en.wikipedia.org/wiki/Puiseux%20series | In mathematics, Puiseux series are a generalization of power series that allow for negative and fractional exponents of the indeterminate. For example, the series
is a Puiseux series in the indeterminate . Puiseux series were first introduced by Isaac Newton in 1676 and rediscovered by Victor Puiseux in 1850.
The definition of a Puiseux series includes that the denominators of the exponents must be bounded. So, by reducing exponents to a common denominator , a Puiseux series becomes a Laurent series in an th root of the indeterminate. For example, the example above is a Laurent series in Because a complex number has th roots, a convergent Puiseux series typically defines functions in a neighborhood of .
Puiseux's theorem, sometimes also called the Newton–Puiseux theorem, asserts that, given a polynomial equation with complex coefficients, its solutions in , viewed as functions of , may be expanded as Puiseux series in that are convergent in some neighbourhood of . In other words, every branch of an algebraic curve may be locally described by a Puiseux series in (or in when considering branches above a neighborhood of ).
Using modern terminology, Puiseux's theorem asserts that the set of Puiseux series over an algebraically closed field of characteristic 0 is itself an algebraically closed field, called the field of Puiseux series. It is the algebraic closure of the field of formal Laurent series, which itself is the field of fractions of the ring of formal power series.
Definition
If is a field (such as the complex numbers), a Puiseux series with coefficients in is an expression of the form
where is a positive integer and is an integer. In other words, Puiseux series differ from Laurent series in that they allow for fractional exponents of the indeterminate, as long as these fractional exponents have bounded denominator (here n). Just as with Laurent series, Puiseux series allow for negative exponents of the indeterminate as long as these negativ |
https://en.wikipedia.org/wiki/Avunculate | The avunculate, sometimes called avunculism or avuncularism, is any social institution where a special relationship exists between an uncle and his sisters' children. This relationship can be formal or informal, depending on the society. Early anthropological research focused on the association between the avunculate and matrilineal descent, while later research has expanded to consider the avunculate in general society.
Definition
The term avunculate comes from the Latin avunculus, the maternal uncle.
The 1989 Oxford English Dictionary defines "avunculate" as follows:
"Avunculate. The special relationship existing in some societies between a maternal uncle and his sister's son; maternal uncles regarded as a collective body.
1920 R. H. LOWIE Prim. Soc. v. 81 Ethnologists describe under the heading of avunculate the customs regulating in an altogether special way the relations of a nephew to his maternal uncle. Ibid. vii. 171 The Omaha are patrilineal now, but their having the avunculate proves that they once traced descent through the mother, for on no other hypothesis can such a usage be explained. ... "
Avunculocal societies
An avunculocal society is one in which a married couple traditionally lives with the man's mother's eldest brother, which most often occurs in matrilineal societies. The anthropological term "avunculocal residence" refers to this convention, which has been identified in about 4% of the world's societies.
This pattern generally occurs when a man obtains his status, his job role, or his privileges from their nearest elder matrilineal male relative. When a woman's son lives near her brother, he is able to more easily learn how he needs to behave in the matrilineal role he has inherited.
Cultures with a formal avunculate
According to the Kazakh common law, the avunculate nephews could take anything from the relatives of the mother up to three times. In the Kyrgyz past a nephew, at a feast at his maternal uncle or grandfather, could take an |
https://en.wikipedia.org/wiki/Belle%20%28chess%20machine%29 | Belle was a chess computer developed by Joe Condon (hardware) and Ken Thompson (software) at Bell Labs. In 1983, it was the first machine to achieve master-level play, with a USCF rating of 2250. It won the ACM North American Computer Chess Championship five times and the 1980 World Computer Chess Championship. It was the first system to win using specialized chess hardware.
In its final incarnation, Belle used an LSI-11 general-purpose computer to coordinate its chess hardware. There were three custom boards for move generation, four custom boards for position evaluation, and a microcode implementation of alpha-beta pruning. The computer also had one megabyte of memory for storing transposition tables.
At the end of its career, Belle was donated to the Smithsonian Institution. The overall architecture of Belle was used for the initial designs of ChipTest, the progenitor of IBM Deep Blue.
Origins
Following his work on the Unix operating system, Ken Thompson turned his attention to computer chess. In summer 1972, he began work on a program for the PDP-11, which would eventually become Belle. In competition, this early version encouraged Thompson to pursue a brute-force approach when designing Belle's hardware.
Design
Belle's design underwent many changes throughout its lifetime. The initial chess program was rewritten to utilize move-vs-evaluation quiescence search and evaluate positions by prioritizing material advantage. Belle also used a transposition table to avoid redundant examinations of positions.
Hardware move generator
In 1976, Joe Condon implemented a hardware move generator to be used with software version of Belle on the PDP-11. His design had several steps:
A 6-bit "from" register searches the board for friendly pieces.
Once a friendly piece is found, a ∆xy move-offset counter provides a bit-code for the move offset, e.g. (2,2) for a bishop or (2,0) for a rook.
This offset is combined with the contents of the "from" register and moved to a 6- |
https://en.wikipedia.org/wiki/Diquat | Diquat is the ISO common name for an organic dication that, as a salt with counterions such as bromide or chloride is used as a contact herbicide that produces desiccation and defoliation. Diquat is no longer approved for use in the European Union, although its registration in many other countries including the USA is still valid.
Synthesis
Pyridine is oxidatively coupled to form 2,2′-bipyridine over a heated Raney nickel catalyst. The ethylene bridge is formed by the reaction with 1,2-dibromoethane
History
Diquat's herbicidal properties were recognized in 1955 in the Imperial Chemical Industries (ICI) laboratories at Jealott's Hill, following its first synthesis at ICI's Dyestuffs Division in Blackley, England. It was active on test plants at application rates as low as 0.1 lb/acre. It was found that only those quaternary salts which were capable of being converted by reducing agents to radical cations had herbicidal activity and another of these was paraquat, which was more effective as a non-selective herbicide than diquat.
Initial attempts to commercialize diquat focused on its ability to control broadleaved annual weeds while damage to cereal crops was, by comparison, minor. However, the auxin herbicides including ICI's MCPA were more selective and hence this use of diquat was unattractive. Instead, diquat was combined with the use of specialised mechanised equipment which by the late 1950s was becoming common in the harvesting of crops such as potatoes. A concern in that use was the possibility that the compound could cause stem-end rot, but protocols were developed that overcame this problem and it was introduced commercially for potato haulm desiccation in 1961.
In the mid 1960s, diquat's use was extended to the pre-harvest desiccation of oilseed crops such as sunflower, linseed, cotton and soya. The patent to the active ingredient has now expired in all countries.
Mode of action
When acting as a herbicide, diquat inhibits photosynthesis. In light-expose |
https://en.wikipedia.org/wiki/Aleste | is a vertically scrolling shooter developed by Compile, originally published by Sega in 1988 for the Master System and then by CP Communications for the MSX2. The Master System version was released outside Japan as Power Strike. The game spawned the Aleste and Power Strike franchises.
Plot
The story of Aleste concerns the manmade supercomputer DIA 51, which has been infected by a hybrid virus that is spreading like wildfire, eventually leading DIA 51 to eliminate the human race. When Yuri, Ray's girlfriend, gets injured in DIA's assault, Raymond Waizen has all the reason in the world to get rid of DIA 51 once and for all in his Aleste fighter.
Releases
The game was originally released for the Master System in February 1988. This version was released outside Japan, as Power Strike. The US release was initially a mail-only limited edition, however it did later see some retail distribution at Toys R' Us and other chains in North America. The European release was a regular retail package.
An MSX2 version was released in July of that year, featuring two new stages, lowered difficulty, and a series of cutscenes.
A version of the game has been released on phones by Square Enix, presumably based on the MSX2 version. The MSX2 version has been re-released on Nintendo's Wii Virtual Console service in Japan. It along with Aleste 2 had also been rereleased through the now-defunct WOOMB service.
Reception
The Master System version called Power Strike received positive reviews. Computer and Video Games scored it 86% in 1989. Console XS scored it 90% in 1992.
Aleste series
Aleste was followed by several sequels:
Aleste Gaiden (MSX2, 1989)
Aleste 2 (MSX2, 1989)
Musha Aleste (Mega Drive, 1990)
GG Aleste (Game Gear, 1991)
Super Aleste (SNES, 1992)
Dennin Aleste (Mega-CD, 1992)
GG Aleste II (Game Gear, 1993)
GG Aleste 3 (Game Gear Micro, 2020)
Senjin Aleste (Arcade, 2021)
Aleste Branch (TBA)
Cancelled games
Dennin Aleste 2 (Mega-CD, cancelled)
Related games
There |
https://en.wikipedia.org/wiki/Chack%27n%20Pop | is a platform arcade game developed and released by Taito in 1984. In the game, the player controls a small yellow creature, Chack'n, with the objective being to retrieve hearts from a cave, all while avoiding the enemies contained within them. Chack'n also has the ability to deploy bombs, which can kill said enemies, which can bring bonuses depending on if all or none of the enemies have been killed.
It is considered to be a spiritual predecessor of Bubble Bobble due to the shared characters and similar game structure. Home ports were released for the SG-1000, MSX, Family Computer, Sharp X1, NEC PC-6001 and NEC PC-8801. The arcade version would later be included via emulation in Taito Legends Power-Up, Taito Memories Pocket, Taito Memories Gekan, and Taito Legends 2. The Family Computer version would later be re-released on the Nintendo Wii and Nintendo 3DS via Virtual Console.
Gameplay
Chack'n Pop is a platform arcade game. The player controls Chack'n, a small yellow creature with extendable legs, through a series of single-screen mazes. He is capable of walking on floors or ceilings but not walls. He can climb steps and traverse high walls by extending his legs until he is tall enough to pass onto the next step. He is also capable of throwing hand grenades to his left or right which, after a short period, explode into a cloud of smoke. Separate fire buttons control rolling to the left or right. Chack'n is killed if caught by the explosion cloud. He is delayed in this process by a series of solid walls. In order to get past the walls, he must free hearts from cages using his hand grenades.
A further obstruction comes in the form of Monstas hatching from eggs. All or none of the Monstas in a level can be destroyed for a bonus at the end of the level. Each screen is played against a time limit, marked by a Mighta pushing a boulder along the top of the screen.
Development and release
Chack'n Pop was released by Taito around April 1984 in Japan, despite the copy |
https://en.wikipedia.org/wiki/Animal%20allergy | In medicine, animal allergy is hypersensitivity to certain substances produced by animals, such as the proteins in animal hair and saliva. It is a common type of allergy.
Signs and symptoms
Symptoms of an allergic reaction to animals may include itchy skin, nasal congestion, itchy nose, sneezing, chronic sore throat or itchy throat, swollen, red, itchy, and watery eyes, coughing, asthma, or rash on the face or chest.
Causes
Allergies are caused by an oversensitive immune system, leading to a misdirected immune response. The immune system normally protects the body against harmful substances such as bacteria and viruses. Allergy occurs when the immune system reacts to substances (allergens) that are generally harmless and in most people do not cause an immune response.
Animal hair and dander
cockroach calyx
dust mite excretion
See also
Cat allergy
List of allergens |
https://en.wikipedia.org/wiki/Bitangent | In geometry, a bitangent to a curve is a line that touches in two distinct points and and that has the same direction as at these points. That is, is a tangent line at and at .
Bitangents of algebraic curves
In general, an algebraic curve will have infinitely many secant lines, but only finitely many bitangents.
Bézout's theorem implies that an algebraic plane curve with a bitangent must have degree at least 4. The case of the 28 bitangents of a quartic was a celebrated piece of geometry of the nineteenth century, a relationship being shown to the 27 lines on the cubic surface.
Bitangents of polygons
The four bitangents of two disjoint convex polygons may be found efficiently by an algorithm based on binary search in which one maintains a binary search pointer into the lists of edges of each polygon and moves one of the pointers left or right at each steps depending on where the tangent lines to the edges at the two pointers cross each other. This bitangent calculation is a key subroutine in data structures for maintaining convex hulls dynamically . describe an algorithm for efficiently listing all bitangent line segments that do not cross any of the other curves in a system of multiple disjoint convex curves, using a technique based on pseudotriangulation.
Bitangents may be used to speed up the visibility graph approach to solving the Euclidean shortest path problem: the shortest path among a collection of polygonal obstacles may only enter or leave the boundary of an obstacle along one of its bitangents, so the shortest path can be found by applying Dijkstra's algorithm to a subgraph of the visibility graph formed by the visibility edges that lie on bitangent lines .
Related concepts
A bitangent differs from a secant line in that a secant line may cross the curve at the two points it intersects it. One can also consider bitangents that are not lines; for instance, the symmetry set of a curve is the locus of centers of circles that are tangent to the |
https://en.wikipedia.org/wiki/Complete%20quadrangle | In mathematics, specifically in incidence geometry and especially in projective geometry, a complete quadrangle is a system of geometric objects consisting of any four points in a plane, no three of which are on a common line, and of the six lines connecting the six pairs of points. Dually, a complete quadrilateral is a system of four lines, no three of which pass through the same point, and the six points of intersection of these lines. The complete quadrangle was called a tetrastigm by , and the complete quadrilateral was called a tetragram; those terms are occasionally still used.
Diagonals
The six lines of a complete quadrangle meet in pairs to form three additional points called the diagonal points of the quadrangle. Similarly, among the six points of a complete quadrilateral there are three pairs of points that are not already connected by lines; the line segments connecting these pairs are called diagonals. For points and lines in the Euclidean plane, the diagonal points cannot lie on a single line, and the diagonals cannot have a single point of triple crossing. Due to the discovery of the Fano plane, a finite geometry in which the diagonal points of a complete quadrangle are collinear, some authors have augmented the axioms of projective geometry with Fano's axiom that the diagonal points are not collinear, while others have been less restrictive.
A set of contracted expressions for the parts of a complete quadrangle were introduced by G. B. Halsted: He calls the vertices of the quadrangle dots, and the diagonal points he calls codots. The lines of the projective space are called straights, and in the quadrangle they are called connectors. The "diagonal lines" of Coxeter are called opposite connectors by Halsted. Opposite connectors cross at a codot. The configuration of the complete quadrangle is a tetrastim.
Projective properties
As systems of points and lines in which all points belong to the same number of lines and all lines contain the same nu |
https://en.wikipedia.org/wiki/Insurance%20score | An insurance score – also called an insurance credit score – is a numerical point system based on select credit report characteristics. There is no direct relationship to financial credit scores used in lending decisions, as insurance scores are not intended to measure creditworthiness, but rather to predict risk. Insurance companies use insurance scores for underwriting decisions, and to partially determine charges for premiums. Insurance scores are applied in personal product lines, namely homeowners and private passenger automobile insurance, and typically not elsewhere.
Background
Insurance scoring models are built from selections of credit report factors, combined with insurance claim and profitability data, to produce numerical formulae or algorithms. A scoring model may be unique to an insurance company and to each line of business (e.g. homeowners or automobile), in terms of the factors selected for consideration and the weighting of the point assignments. As insurance credit scores are not intended to measure creditworthiness, they commonly focus on financial habits and choices (i.e., age of oldest account, number of inquiries in 24 months, ratio of total balance to total limits, number of open retail credit cards, number of revolving accounts with balances greater than 75% of limits, etc.) Therefore it is possible for a consumer with a high financial credit score, and excellent payment history, to receive a poor insurance score. Insurers consider credit report information in their underwriting and pricing decisions as a predictor of profitability and risk of loss.
Various studies have found a strong relationship between credit-based insurance scores and profitability or risk of loss. The scores are generally most predictive when little or no other information exists, such as in the case of clean driving records, or claims-free policies; in instances where past claims, points, or other similar information exist on record, the personal histories will ty |
https://en.wikipedia.org/wiki/Herbrand%20Award | The Herbrand Award for Distinguished Contributions to Automated Reasoning is an award given by the Conference on Automated Deduction (CADE), Inc., (although it predates the formal incorporation of CADE) to honour persons or groups for important contributions to the field of automated deduction. The award is named after the French scientist Jacques Herbrand and given at most once per CADE or International Joint Conference on Automated Reasoning (IJCAR). It comes with a prize of US$1,000. Anyone can be nominated, the award is awarded after a vote among CADE trustees and former recipients, usually with input from the CADE/IJCAR programme committee.
Recipients
Past award recipients are:
1990s
Larry Wos (1992)
Woody Bledsoe (1994)
John Alan Robinson (1996)
Wu Wenjun (1997)
Gérard Huet (1998)
Robert S. Boyer and J Strother Moore (1999)
2000s
William W. McCune (2000)
Donald W. Loveland (2001)
Mark E. Stickel (2002).
Peter B. Andrews (2003)
Harald Ganzinger (2004)
Martin Davis (2005)
Wolfgang Bibel (2006)
Alan Bundy (2007)
Edmund M. Clarke (2008)
Deepak Kapur (2009)
2010s
David Plaisted (2010)
Nachum Dershowitz (2011)
Melvin Fitting (2012)
C. Greg Nelson (2013)
Robert L. Constable (2014)
Andrei Voronkov (2015)
Zohar Manna and Richard Waldinger (2016)
Lawrence C. Paulson (2017)
Bruno Buchberger (2018)
Nikolaj Bjørner and Leonardo de Moura (2019)
2020s
Franz Baader (2020)
Tobias Nipkow (2021)
Natarajan Shankar (2022)
See also
List of computer science awards
Jacques Herbrand Prize — by the French Academy of Sciences, for mathematics and physics |
https://en.wikipedia.org/wiki/Complete%20numbering | In computability theory complete numberings are generalizations of Gödel numbering first introduced by A.I. Mal'tsev in 1963. They are studied because several important results like the Kleene's recursion theorem and Rice's theorem, which were originally proven for the Gödel-numbered set of computable functions, still hold for arbitrary sets with complete numberings.
Definition
A numbering of a set is called complete (with respect to an element ) if for every partial computable function there exists a total computable function so that (Ershov 1999:482):
Ershov refers to the element a as a "special" element for the numbering. A numbering is called precomplete if the weaker property holds:
Examples
Any numbering of a singleton set is complete
The identity function on the natural numbers is not complete
A Gödel numbering is precomplete |
https://en.wikipedia.org/wiki/B%20chromosome | In addition to the normal karyotype, wild populations of many animal, plant, and fungi species contain B chromosomes (also known as supernumerary, accessory, (conditionally-)dispensable, or lineage-specific chromosomes). By definition, these chromosomes are not essential for the life of a species, and are lacking in some (usually most) of the individuals. Thus a population would consist of individuals with 0, 1, 2, 3 (etc.) B chromosomes. B chromosomes are distinct from marker chromosomes or additional copies of normal chromosomes as they occur in trisomies.
Origin
The evolutionary origin of supernumerary chromosomes is obscure, but presumably, they must have been derived from heterochromatic segments of normal chromosomes in the remote past. In general "we may regard supernumeraries as a very special category of genetic polymorphism which, because of manifold types of accumulation mechanisms, does not obey the ordinary Mendelian laws of inheritance." (White 1973 p173)
Next generation sequencing has shown that the B chromosomes from rye are amalgamations of the rye A chromosomes. Similarly, B chromosomes of the cichlid fish Haplochromis latifasciatus also have been shown to arise from rearrangements of normal A chromosomes.
Function
Most B chromosomes are mainly or entirely heterochromatic (i.e. largely non-coding), but some contain sizeable euchromatic segments (e.g. such as the B chromosomes of maize). In some cases, B chromosomes act as selfish genetic elements. In other cases, B chromosomes provide some positive adaptive advantage. For instance, the British grasshopper Myrmeleotettix maculatus has two structural types of B chromosomes: metacentrics and submetacentric. The supernumeraries, which have a satellite DNA, occur in warm, dry environments, and are scarce or absent in humid, cooler localities.
There is evidence of deleterious effects of supernumeraries on pollen fertility, and favourable effects or associations with particular habitats are also kno |
https://en.wikipedia.org/wiki/Rumex%20acetosella | Rumex acetosella, commonly known as red sorrel, sheep's sorrel, field sorrel and sour weed, is a species of flowering plant in the buckwheat family Polygonaceae. Native to Eurasia and the British Isles, the plant and its subspecies are common perennial weeds. It has green arrowhead-shaped leaves and red-tinted deeply ridged stems, and it sprouts from an aggressive and spreading rhizome. The flowers emerge from a tall, upright stem. Female flowers are maroon in color.
Description
Rumex acetosella is a perennial herb which spreads via rhizomes. It has a slender and reddish, upright stem that is branched at the top, reaching a height of . The arrow-shaped leaves are small, about long and wide, with pointed lobes at the base. It blooms during March to November, when yellowish-green (male) or reddish (female) flowers develop on separate plants at the apex of the stem, which develop into the red fruits (achenes).
It should not be confused with the similarly named R. acerosella, which also contains oxalic acid and should not be eaten in excess.
Distribution and habitat
Native to Eurasia and the British Isles, R. acetosella has been introduced to most of the rest of the Northern Hemisphere. It is commonly found on acidic, sandy soils in heaths and grassland. It is often one of the first species to take hold in disturbed areas, such as abandoned mining sites, especially if the soil is acidic.
The plant is dioecious, with separate male and female plants. It has been found that in early successional habitats, there are relatively more female plants, while in later successional stages, male plants are more common.
Ecology
Livestock will graze on the plant, but it is not very nutritious and is toxic in large amounts because of oxalates. Italian agronomist Nicola Onorati (1764–1822) first discovered that the plant damages the teeth of animals that crop this plant because of the oxalic acid it contains.
Ground-feeding songbirds eat the seeds, and larger animals like rabbit |
https://en.wikipedia.org/wiki/Macromolecular%20docking | Macromolecular docking is the computational modelling of the quaternary structure of complexes formed by two or more interacting biological macromolecules. Protein–protein complexes are the most commonly attempted targets of such modelling, followed by protein–nucleic acid complexes.
The ultimate goal of docking is the prediction of the three-dimensional structure of the macromolecular complex of interest as it would occur in a living organism. Docking itself only produces plausible candidate structures. These candidates must be ranked using methods such as scoring functions to identify structures that are most likely to occur in nature.
The term "docking" originated in the late 1970s, with a more restricted meaning; then, "docking" meant refining a model of a complex structure by optimizing the separation between the interactors but keeping their relative orientations fixed. Later, the relative orientations of the interacting partners in the modelling was allowed to vary, but the internal geometry of each of the partners was held fixed. This type of modelling is sometimes referred to as "rigid docking". With further increases in computational power, it became possible to model changes in internal geometry of the interacting partners that may occur when a complex is formed. This type of modelling is referred to as "flexible docking".
Background
The biological roles of most proteins, as characterized by which other macromolecules they interact with, are known at best incompletely. Even those proteins that participate in a well-studied biological process (e.g., the Krebs cycle) may have unexpected interaction partners or functions which are unrelated to that process.
In cases of known protein–protein interactions, other questions arise. Genetic diseases (e.g., cystic fibrosis) are known to be caused by misfolded or mutated proteins, and there is a desire to understand what, if any, anomalous protein–protein interactions a given mutation can cause. In the dis |
https://en.wikipedia.org/wiki/Paleopolyploidy | Paleopolyploidy is the result of genome duplications which occurred at least several million years ago (MYA). Such an event could either double the genome of a single species (autopolyploidy) or combine those of two species (allopolyploidy). Because of functional redundancy, genes are rapidly silenced or lost from the duplicated genomes. Most paleopolyploids, through evolutionary time, have lost their polyploid status through a process called diploidization, and are currently considered diploids, e.g., baker's yeast, Arabidopsis thaliana, and perhaps humans.
Paleopolyploidy is extensively studied in plant lineages. It has been found that almost all flowering plants have undergone at least one round of genome duplication at some point during their evolutionary history. Ancient genome duplications are also found in the early ancestor of vertebrates (which includes the human lineage) near the origin of the bony fishes, and another in the stem lineage of teleost fishes. Evidence suggests that baker's yeast (Saccharomyces cerevisiae), which has a compact genome, experienced polyploidization during its evolutionary history.
The term mesopolyploid is sometimes used for species that have undergone whole genome multiplication events (whole genome duplication, whole genome triplification, etc.) in more recent history, such as within the last 17 million years.
Eukaryotes
Ancient genome duplications are widespread throughout eukaryotic lineages, particularly in plants. Studies suggest that the common ancestor of Poaceae, the grass family which includes important crop species such as maize, rice, wheat, and sugar cane, shared a whole genome duplication about . In more ancient monocot lineages one or likely multiple rounds of additional whole genome duplications had occurred, which were however not shared with the ancestral eudicots. Further independent more recent whole genome duplications have occurred in the lineages leading to maize, sugar cane and wheat, but not ric |
https://en.wikipedia.org/wiki/Colobot | Colobot (Colonize with Bots) is an educational, post apocalyptic real-time strategy video game featuring 3D graphics, created by Swiss developer Epsitec SA. The objective of the game is to find a planet for colonization by the human race by establishing a basic infrastructure on the surface and eliminating any alien life forms endangering the expedition. The game takes place on the Earth, Moon, and seven fictional planets. The main feature of the game, which makes it educational, is the possibility for players to program their robots using a programming language similar to C++ or Java.
Plot overview
Life on earth is threatened by a devastating cataclysm, forcing mankind to move out and search for a new home. A first expedition composed solely of robots was sent to find another habitable planet. However, for unknown reasons, the mission was a disaster and never returned.
With only a few robots for companions, the player must travel to new planets. Houston, Earth Mission Control as well as a spy satellite will transmit valuable information to the player. The player needs to build the infrastructure necessary to gather raw materials, energy supplies, and produce the weapons necessary to defend themselves. By programming robots, the player can delegate tasks to them, allowing the player to continue their mission while their robots upkeep the base, fight off enemies, harvest materials, and perform any other tasks assigned to them.
Missions
In the game, the player explores Earth, Moon and seven fictional planets.
Language overview
The programming language used in is CBOT, syntactically similar to C++ and Java. Example code for a bot to find a piece of titanium ore and deliver it to a purification facility:
extern void object::FetchTitanium()
{
object item; // declare variable
item = radar(TitaniumOre); // find a piece of titanium ore
goto(item.position); // go to the ore
grab(); // pick up whatever is in front of the robot (presumably the ore)
item = |
https://en.wikipedia.org/wiki/Interval%20exchange%20transformation | In mathematics, an interval exchange transformation is a kind of dynamical system that generalises circle rotation. The phase space consists of the unit interval, and the transformation acts by cutting the interval into several subintervals, and then permuting these subintervals. They arise naturally in the study of polygonal billiards and in area-preserving flows.
Formal definition
Let and let be a permutation on . Consider a vector of positive real numbers (the widths of the subintervals), satisfying
Define a map called the interval exchange transformation associated with the pair as follows. For let
Then for , define
if lies in the subinterval . Thus acts on each subinterval of the form by a translation, and it rearranges these subintervals so that the subinterval at position is moved to position .
Properties
Any interval exchange transformation is a bijection of to itself that preserves the Lebesgue measure. It is continuous except at a finite number of points.
The inverse of the interval exchange transformation is again an interval exchange transformation. In fact, it is the transformation where for all .
If and (in cycle notation), and if we join up the ends of the interval to make a circle, then is just a circle rotation. The Weyl equidistribution theorem then asserts that if the length is irrational, then is uniquely ergodic. Roughly speaking, this means that the orbits of points of are uniformly evenly distributed. On the other hand, if is rational then each point of the interval is periodic, and the period is the denominator of (written in lowest terms).
If , and provided satisfies certain non-degeneracy conditions (namely there is no integer such that ), a deep theorem which was a conjecture of M.Keane and due independently to William A. Veech and to Howard Masur asserts that for almost all choices of in the unit simplex the interval exchange transformation is again uniquely ergodic. However, for there also ex |
https://en.wikipedia.org/wiki/Cylindrification | In computability theory a cylindrification is a construction that associates a cylindric numbering to each numbering. The concept was first introduced by Yuri L. Ershov in 1973.
Definition
Given a numbering , the cylindrification is defined as
where is the Cantor pairing function.
Note that the cylindrification operation increases the input arity by 1.
Properties
Given two numberings and then |
https://en.wikipedia.org/wiki/Creative%20and%20productive%20sets | In computability theory, productive sets and creative sets are types of sets of natural numbers that have important applications in mathematical logic. They are a standard topic in mathematical logic textbooks such as and .
Definition and example
For the remainder of this article, assume that is an admissible numbering of the computable functions and Wi the corresponding numbering of the recursively enumerable sets.
A set A of natural numbers is called productive if there exists a total recursive (computable) function so that for all , if then The function is called the productive function for
A set A of natural numbers is called creative if A is recursively enumerable and its complement is productive. Not every productive set has a recursively enumerable complement, however, as illustrated below.
The archetypal creative set is , the set representing the halting problem. Its complement is productive with productive function f(i) = i (the identity function).
To see this, we apply the definition of a productive function and show separately that and :
: suppose , then , now given that we have , this leads to a contradiction. So .
: in fact if , then it would be true that , but we have demonstrated the contrary in the previous point. So .
Properties
No productive set A can be recursively enumerable, because whenever A contains every number in an r.e. set Wi it contains other numbers, and moreover there is an effective procedure to produce an example of such a number from the index i. Similarly, no creative set can be decidable, because this would imply that its complement, a productive set, is recursively enumerable.
Any productive set has a productive function that is injective and total.
The following theorems, due to Myhill (1955), show that in a sense all creative sets are like and all productive sets are like .
Theorem. Let P be a set of natural numbers. The following are equivalent:
P is productive.
is 1-reducible to P.
is m-reducible |
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