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https://en.wikipedia.org/wiki/Curve%20fitting | Curve fitting is the process of constructing a curve, or mathematical function, that has the best fit to a series of data points, possibly subject to constraints. Curve fitting can involve either interpolation, where an exact fit to the data is required, or smoothing, in which a "smooth" function is constructed that approximately fits the data. A related topic is regression analysis, which focuses more on questions of statistical inference such as how much uncertainty is present in a curve that is fit to data observed with random errors. Fitted curves can be used as an aid for data visualization, to infer values of a function where no data are available, and to summarize the relationships among two or more variables. Extrapolation refers to the use of a fitted curve beyond the range of the observed data, and is subject to a degree of uncertainty since it may reflect the method used to construct the curve as much as it reflects the observed data.
For linear-algebraic analysis of data, "fitting" usually means trying to find the curve that minimizes the vertical (y-axis) displacement of a point from the curve (e.g., ordinary least squares). However, for graphical and image applications, geometric fitting seeks to provide the best visual fit; which usually means trying to minimize the orthogonal distance to the curve (e.g., total least squares), or to otherwise include both axes of displacement of a point from the curve. Geometric fits are not popular because they usually require non-linear and/or iterative calculations, although they have the advantage of a more aesthetic and geometrically accurate result.
Algebraic fitting of functions to data points
Most commonly, one fits a function of the form .
Fitting lines and polynomial functions to data points
The first degree polynomial equation
is a line with slope a. A line will connect any two points, so a first degree polynomial equation is an exact fit through any two points with distinct x coordinates.
If the order of the equation is increased to a second degree polynomial, the following results:
This will exactly fit a simple curve to three points.
If the order of the equation is increased to a third degree polynomial, the following is obtained:
This will exactly fit four points.
A more general statement would be to say it will exactly fit four constraints. Each constraint can be a point, angle, or curvature (which is the reciprocal of the radius of an osculating circle). Angle and curvature constraints are most often added to the ends of a curve, and in such cases are called end conditions. Identical end conditions are frequently used to ensure a smooth transition between polynomial curves contained within a single spline. Higher-order constraints, such as "the change in the rate of curvature", could also be added. This, for example, would be useful in highway cloverleaf design to understand the rate of change of the forces applied to a car (see jerk), as it follows the cloverleaf, |
https://en.wikipedia.org/wiki/CKND-DT | CKND-DT (channel 9) is a television station in Winnipeg, Manitoba, Canada, part of the Global Television Network. The station is owned and operated by network parent Corus Entertainment, with studios on the 30th floor of 201 Portage in downtown Winnipeg, and transmitter atop the building.
History
Acquisition and licensing
CKND's predecessor, KCND-TV, began broadcasting from Pembina, North Dakota, in November 1960. Although a U.S. station, it depended almost entirely on advertising from the media market of Winnipeg, Manitoba, Canada. In February 1973, the Canadian Radio-television and Telecommunications Commission (CRTC) announced that it had received two applications for new television stations in Winnipeg. One had been submitted by Western Manitoba Broadcasters Ltd., the parent company of CKX-TV in Brandon, Manitoba. The other application had been received from Continental Communications Ltd. of Vancouver, British Columbia, represented by Ray Peters, the president of Vancouver CTV affiliate CHAN-TV.
The CRTC solicited competing applications for the new Winnipeg television licence, and Peter Liba, who was then the executive assistant to Manitoba Liberal Party leader Izzy Asper, suggested that they make a bid. Wanting to save money on buying the needed equipment, Asper negotiated with Gordon McLendon to acquire the assets of KCND, convincing him that a new Winnipeg station would cut into KCND's revenues and that Winnipeg advertisers would likely lose tax deductions for American advertising costs.
McLendon sold the station's facilities and equipment to Canwest Broadcasting, established by Asper and partners Paul Morton and Seymour Epstein, for $780,000, contingent on Canwest securing a broadcasting licence. At the CRTC's public hearings in Winnipeg in May 1974, Canwest noted that the acquisition of KCND would give their new Winnipeg station a $2 million advertising base and would save $1.5 million in capital and start-up costs compared to the alternative of launching a completely new station.
At the same hearing, competing applications were presented by Western Manitoba Broadcasters Ltd. and by Communications Winnipeg Co-Op, which proposed a member-supported non-commercial station. (Continental Communications had withdrawn its application prior to the hearings.) John Boler, the owner of Valley City–Fargo, North Dakota CBS affiliate KXJB-TV and future owner of KVRR/KNRR, also used the occasion to announce his intention to launch a new Pembina-based station on channel 12.
In September 1974, the CRTC awarded the Winnipeg channel 9 licence to Canwest, which formally took possession and assumed day-to-day management of KCND-TV on March 31, 1975 (due to foreign ownership restrictions, the McLendon Corporation remained the official licensee of KCND until it surrendered the station's broadcasting licence to the U.S. Federal Communications Commission [FCC] later that year). The same month, Canwest confirmed that the new station would operate from a fo |
https://en.wikipedia.org/wiki/Chromosome%20%28genetic%20algorithm%29 | In genetic algorithms (GA), or more general, evolutionary algorithms (EA), a chromosome (also sometimes called a genotype) is a set of parameters which define a proposed solution of the problem that the evolutionary algorithm is trying to solve. The set of all solutions, also called individuals according to the biological model, is known as the population. The genome of an individual consists of one, more rarely of several, chromosomes and corresponds to the genetic representation of the task to be solved. A chromosome is composed of a set of genes, where a gene consists of one or more semantically connected parameters, which are often also called decision variables. They determine one or more phenotypic characteristics of the individual or at least have an influence on them. In the basic form of genetic algorithms, the chromosome is represented as a binary string, while in later variants and in EAs in general, a wide variety of other data structures are used.
Chromosome design
When creating the genetic representation of a task, it is determined which decision variables and other degrees of freedom of the task should be improved by the EA and possible additional heuristics and how the genotype-phenotype mapping should look like. The design of a chromosome translates these considerations into concrete data structures for which an EA then has to be selected, configured, extended, or, in the worst case, created. Finding a suitable representation of the problem domain for a chromosome is an important consideration, as a good representation will make the search easier by limiting the search space; similarly, a poorer representation will allow a larger search space. In this context, suitable mutation and crossover operators must also be found or newly defined to fit the chosen chromosome design. An important requirement for these operators is that they not only allow all points in the search space to be reached in principle, but also make this as easy as possible.
The following requirements must be met by a well-suited chromosome:
It must allow the accessibility of all admissible points in the search space.
Design of the chromosome in such a way that it covers only the search space and no additional areas. so that there is no redundancy or only as little redundancy as possible.
Observance of strong causality: small changes in the chromosome should only lead to small changes in the phenotype. This is also called locality of the relationship between search and problem space.
Designing the chromosome in such a way that it excludes prohibited regions in the search space completely or as much as possible.
While the first requirement is indispensable, depending on the application and the EA used, one usually only has to be satisfied with fulfilling the remaining requirements as far as possible. It should be noted, however, that the evolutionary search is supported and possibly considerably accelerated by a fulfillment as complete as possible.
Exa |
https://en.wikipedia.org/wiki/WITN-TV | WITN-TV (channel 7) is a television station licensed to Washington, North Carolina, United States, serving Eastern North Carolina as an affiliate of NBC and MyNetworkTV. Owned by Gray Television, the station has primary studio facilities on East Arlington Boulevard in Greenville, with an additional studio in New Bern. Its transmitter is located in Grifton Township along NC 118.
History
The station signed on September 28, 1955, from facilities on US 17 in Chocowinity (outside Washington, though with a Washington mailing address). It was the area's second television outlet to launch after Greenville's WNCT-TV (channel 9). It was an NBC affiliate from the start but shared secondary ABC relations with WNCT until the 1963 sign-on of WNBE-TV (channel 12, now WCTI-TV) in New Bern. WITN's first broadcast was game 1 of the 1955 World Series.
WITN aired an analog signal on VHF channel 7 from the region's highest transmitter at that time. The station was originally owned by North Carolina Television, a consortium of radio stations from Northeastern North Carolina. Majority ownership was held by the Roberson family, owners of WITN radio (930 AM, now WDLX; and FM 93.3, now WERO).
The group held onto the television station until 1985, when it was sold to AFLAC. It added the -TV suffix to its call sign on July 31, 1978. In 1997, AFLAC sold its broadcasting group to Retirement Systems of Alabama which merged with Ellis Communications to form Raycom Media. However, Raycom could not keep WITN for long due to a significant signal overlap with Wilmington's WECT, an Ellis property that was part of the deal. WITN's city-grade signal reaches the northern portion of the Wilmington market. At the time, the FCC normally did not allow one company to own two stations with overlapping signals, and would not even consider a waiver for a city-grade overlap. What was then known as Gray Communications (now Gray Television) bought the station later in 1997. It has been broadcasting a full-power digital signal since June 2006. They eventually reunited in 2019 after Gray acquired Raycom, but by then, overlaps of signals were not considered as long as the stations were in separate markets.
On January 7, 2009, a high definition feed of WITN was launched on DirecTV and can now also be obtained on Dish Network. It switched to digital-only broadcasting on June 12. However, WITN has been digital-only since February 19, 2009. In June 2013, the station moved from its longtime home outside Washington to new high definition-ready studios in Greenville.
In addition to offering network and syndicated programming, WITN was also a multimedia rights partner for East Carolina University Athletics from 1998 to 2014. In addition to hosting the weekly coaches' shows for football and basketball, the station produced live broadcasts of select games that were not picked up nationally by ESPN as part of its deal with Conference USA. Even though most of the broadcasts were limited to its own market, |
https://en.wikipedia.org/wiki/Clone%20High | Clone High is an adult animated science fiction sitcom created by Phil Lord, Christopher Miller and Bill Lawrence that premiered on Canadian cable channel Teletoon's late-night programming block The Detour On Teletoon on November 2, 2002. Set at a high school populated by the clones of well-known historical figures, the series follows its central cast which includes adolescent depictions of Abe Lincoln, Joan of Arc, Gandhi, Cleopatra, and JFK. The series also serves as a parody of teen dramas such as Dawson's Creek and Beverly Hills, 90210; every episode is introduced as a "very special episode".
Lord and Miller first developed the series' concept, originally titled Clone High School, USA!, while at Dartmouth College in the 1990s, later pitching it to executives at US network Fox Broadcasting Company, who ultimately decided to pass on the program. It was later purchased by cable channel MTV, and was produced between 2002 and 2003. The show's design is heavily stylized and its animation style limited, emphasizing humor and story over visuals. The Clone High theme song was written by Tommy Walter and performed by his alternative rock band Abandoned Pools, who also provided much of the series' background music.
It was first aired in its entirety on Teletoon between 2002 and 2003, later premiering on MTV on January 20, 2003. It became embroiled in controversy regarding its depiction of Gandhi soon afterward, which prompted over 100 people in India to mount a hunger strike in response. Shortly after, MTV cancelled the series, which had been receiving low ratings; the last episodes were seen in 2016 on MTV Classic in the United States. Clone High attracted mixed reviews from television critics upon its premiere, but it has since received critical acclaim and a cult following.
On July 2, 2020, it was announced that a revival of the series was in the works at MTV Entertainment Studios with the original creators Lord, Miller, and Lawrence returning. On February 10, 2021, it was announced that HBO Max (later Max) had ordered two seasons of the revival, which premiered on May 23, 2023, with season 2 releasing two new episodes on Tuesdays until June 22. On April 5, 2023, a teaser for the revival was uploaded on Max's official YouTube channel. The final trailer was released on May 8.
Premise
Clone High is set in a high school in the fictional town of Exclamation, USA, that is secretly being run as an elaborate military experiment orchestrated by a government office called the Secret Board of Shadowy Figures. The school is entirely populated by the clones of famous historical figures that were created in the 1980s and raised with the intent of having their various strengths and abilities harnessed by the United States military. The principal of the high school, Cinnamon J. Scudworth, has his own plans for the clones, and secretly tries to undermine the wishes of the Board (Scudworth wants to use the clones to create a clone-themed amusement park, dubbed "C |
https://en.wikipedia.org/wiki/Chameleon%20%28computing%29 | Chameleon is a computer workstation design produced at ETH Zurich running the Oberon operating system.
The Seequa Chameleon was also an older luggable computer from the early 1980s, distinguished by being able to run both the MS-DOS and CP/M-80 operating systems.
References
Computer workstations |
https://en.wikipedia.org/wiki/Hong%20Kong%20Olympiad%20in%20Informatics | Hong Kong Olympiad in Informatics (HKOI; 香港電腦奧林匹克競賽) is an annual programming competition for secondary school students in Hong Kong, emphasizing on problem solving techniques and programming skills. It is co-organized by the Hong Kong Association for Computer Education (HKACE) and the Hong Kong Education Bureau (EDB). It serves as a preliminary contest to international, national and regional competitions such as the China National Olympiad in Informatics (NOI) and the International Olympiad in Informatics (IOI). The first HKOI was held in 1997.
History
Hong Kong first participated in IOI in 1992. In order select representatives for the Hong Kong Delegation Team, a selection test was held a few months before the competition. In the following years, Hong Kong started sending teams to other competitions, including the SEARCC International Schools' Software Competition (ISSC) in 1993, the Software Competition for the Youths (SCY) in 1994 and the China National Olympiad in Informatics in 1995. Selection tests were separately administered for these competitions, and the purpose of each test was solely to select team members for the competitions. A considerable amount of resources were used to organize these tests. The tests were not very popular among students in Hong Kong.
In 1996, the Hong Kong Association for Computer Education, the Hong Kong Computer Society and the Education Department of Hong Kong (now the Education Bureau) jointly organized the Joint Selection Contest to replace all the selection tests. 39 students were selected as seeds for the Hong Kong teams. They received intensive training on topics like data structures and algorithms. After that, a Team Formation Test was conducted to select the Hong Kong representatives in IOI and NOI among the seeds. Another Team Formation Test was conducted for the SEARCC-ISSC and SCY.
In 1997, the Joint Selection Contest was renamed as the Hong Kong Olympiad in Informatics. Prizes are awarded to students with good results in HKOI, who are then invited to join the HKOI Training Team. Due to the limit on the number of participants from each school, some schools organize their own team formation test to select students to take part in HKOI.
Structure of the Competition
Groupings
The participants of HKOI are divided into two groups. The Junior Group consists of students aged 17 or below, and the Senior Group consists of students aged 19 or below. The rationale of having two groups with one having an age limit of 17 is that SEARCC-ISSC requires all participants to be aged 17 or below. Another advantage of having a Junior Group is to allow more young students to enter the HKOI training team without having to compete with the more experienced senior students.
Competition format
The competition format of the HKOI has changed a few times since the introduction of Joint Selection Contest in 1996.
The Joint Selection Contest was conducted in written format. All programs were written down on the answer sh |
https://en.wikipedia.org/wiki/Michael%20Capellas | Michael David Capellas (born August 19, 1954) is an American executive in the computer and telecommunication industries. Capellas served as chairman and CEO of First Data Corporation, acting CEO of Serena Software, chairman and CEO of Compaq Computer Corporation until its merger with Hewlett-Packard where he became president of the post-merger company briefly, and president and CEO of WorldCom (later MCI) where he led its merger with Verizon.
Early years
Capellas claims that he inherited a gritty determination from his father, a Greek citizen who fought with the Greek Army against the Germans in Italy in World War II. After the war, the elder Capellas met and married his wife, Juliet, in Italy. The family then emigrated to Ohio where Capellas' father worked his way up from laborer to superintendent at the Republic Steel Corp. My dad had an unbelievable work ethic. He was intensely loyal to the company. He worked there for 30 years, says Capellas.
As an undergraduate at Kent State University, Capellas developed an interest in computers. Shortly after he graduated with a BBA from Kent State, Capellas met his future wife, Marie Angelillo, a former nurse. The two married in 1979, and for the next 20 years they traveled around the world as Capellas climbed the ranks of each company he joined.
Business
Capellas began his career at Republic Steel. He went on to hold senior executive roles at Schlumberger, Benchmarking Partners, SAP, and Oracle Corporation. Capellas joined Compaq Computer Corporation as CIO in 1998. In 1999, when president and chief executive officer (CEO) Eckhard Pfeiffer was forced to resign after a boardroom coup led by chairman Benjamin M. Rosen, Rosen took on the capacity of interim CEO while Capellas was elevated to COO. Several months later, Capellas became permanent CEO and Chairman of Compaq.
As chairman and CEO of Compaq between 1999 and 2001, Capellas helped repair the relationship between Microsoft and Compaq, which had eroded over the years. His efforts resulted in Compaq becoming Microsoft's key strategic partner for the release of its Windows 2000 operating system.
In 2001, Capellas led Compaq into an acquisition by Hewlett-Packard, but the deal was delayed for eight months because of a proxy and boardroom battle within HP. Finally, on May 3, 2002, Hewlett-Packard announced approval of the acquisition and Capellas became president of the post-merger Hewlett-Packard, under CEO Carly Fiorina, to ease the integration of the two companies. However, Capellas was reported not to be happy with his role, being said not to be utilized and being unlikely to become CEO as the board supported Fiorina. Capellas stepped down on November 12, 2002, just six months on the job. His former role of president was not filled as the executives who reported to him then reported directly to the CEO.
In December 2002, Capellas became the turnaround president and CEO of WorldCom (later MCI). He led a successful restructuring of the organiz |
https://en.wikipedia.org/wiki/Star%20Trek%20project | Star Trek is the code name that was given to a secret prototype project, running a port of Macintosh System 7 and its applications on Intel-compatible x86 personal computers. The project, starting in February 1992, was conceived in collaboration between Apple Computer, who provided the majority of engineers, and Novell, who at the time was one of the leaders of cross-platform file-servers. The plan was that Novell would market the resulting OS as a challenge to Microsoft Windows, but the project was discontinued in 1993 and never released, although components were reused in other projects. The project was named after the Star Trek science fiction franchise with the slogan "To boldly go where no Mac has gone before".
History
The impetus for the creation of the Star Trek project began out of Novell's desire to increase its competition against the monopoly of Microsoft and its DOS-based Windows products. While Microsoft was eventually convicted many years later of illegal monopoly status, Novell had called Microsoft's presence "predatory" and the US Department of Justice had called it "exclusionary" and "unlawful". Novell's first idea to extend its desktop presence with a graphical computing environment was to adapt Digital Research's GEM desktop environment, but Novell's legal department rejected this due to apprehension of a possible legal response from Apple, so the company went directly to Apple. With shared concerns in the anti-competitive marketplace, Intel's CEO Andy Grove supported the two companies in launching their joint project Star Trek on February 14, 1992 (Valentine's Day).
Apple set a deadline of October 31, 1992 (Halloween Day), promising the engineering team members a performance bonus of a large cash award and a vacation in Cancun, Mexico. Of the project, team member Fred Monroe later reflected, "We worked like dogs. It was some of the most fun I've had working".
Achieving their deadline goal and receiving their bonuses, the developers eventually reached a point where they could boot an Intel 486 PC (with very specific hardware) into System 7.1, and its on-screen appearance was indistinguishable from a Mac. However, every program would then need to be ported to the new x86 architecture to run. It was to sit on top of a then upcoming release of DR DOS and it was noted that programs would have to be recompiled.
The tagline for the project was "to boldly go where no Mac has gone before", which Computerworld mocked with the comment "the OS that boldly goes where everyone else has been".
However, the project was canceled in mid-1993 because of political infighting, personnel issues, and the questionable marketability of such a project. Apple's side of the project had seen the exit of a supportive CEO, John Sculley, in favor of a new CEO, Michael Spindler. Spindler was not interested in the project, instead reallocating most software engineering resources toward the company's total migration to the competing PowerPC architecture. |
https://en.wikipedia.org/wiki/Computer%20World | Computer World () is the eighth studio album by German electronic band Kraftwerk, released on 11 May 1981.
The album deals with the themes of the rise of computers within society. In keeping with the album's concept, Kraftwerk showcased their music on an ambitious world tour. The compositions are credited to Ralf Hütter, Florian Schneider, and Karl Bartos. As was the case with the two previous albums, Computer World was released in both German- and English-language editions.
Concept and recording
"We live in a computer world, so we made a song about it", said mastermind Ralf Hütter. Computer World has been described as a futuristic conceptual work that predicts the presence of computer technology in every day life. Featuring themes such as home computers and digital communication, the album has been seen as both a celebration of computer technology as well as a warning about its potential to exert power on society with social control and digital surveillance. Despite its theme, the production of the album was completely analogue and did not involve any computer technology.
Artwork
The cover shows a computer terminal (apparently based on one made by the Hazeltine Corporation) displaying the heads of the four band members.
The inner sleeve artwork, created by Emil Schult and photographed by Günter Fröhling, depicts four slightly robotic-looking mannequins (representing the band members engaged in studio activities: performing, recording, mixing), similar to the artwork of the previous album, The Man-Machine, also created by Fröhling. In two photos, the mannequin representing Karl Bartos is seen playing a Stylophone, an instrument which is featured on the track "Pocket Calculator".
Release
Computer World peaked at on the UK Albums Chart. It was certified silver by the British Phonographic Industry (BPI) on 12 February 1982 for shipments in excess of 60,000 copies.
The track "Computer Love" was released as a seven-inch single in the UK, in July 1981, backed with "The Model", from the group's previous album The Man-Machine. The single reached in the charts. In November 1981 the two songs were reissued as a double A-side twelve-inch single, and reached on the UK Singles Chart in February 1982, although "The Model" received the most airplay.
"Pocket Calculator" was released as a seven-inch single in the USA by Warner Brothers in 1981, pressed on a fluorescent yellow/lime vinyl, matching the color of the album cover. The flip side featured the Japanese version of "Pocket Calculator," "Dentaku". “Pocket Calculator” charted at No.38 in the UK Singles Chart.
"Computerwelt" was remixed in 1982 as a dance version with additional bass and percussion sounds. It was released in January 1982 as a twelve-inch vinyl single only in Germany. The original track was nominated for a Grammy Award for Best Rock Instrumental Performance in 1982. "Computer World" was also chosen by the BBC for use in the titles of their UK computer literacy project, The Computer |
https://en.wikipedia.org/wiki/VFP | VFP may stand for:
VFP (instruction set), an extension to the ARM instruction set
Visual FoxPro, a programming language
All-Russia Fascist Party (1930s–1942)
Very Fast Picket, a class of fictional artificially intelligent starship in The Culture universe of late Scottish author Iain Banks
Veterans Freedom Party, a minor party in the Philippines
Veterans for Peace, an anti-war organisation in the United States and other countries |
https://en.wikipedia.org/wiki/UKOLN | Formerly known as The United Kingdom Office for Library and Information Networking, UKOLN was a centre of expertise in digital information management, providing advice and services to the library, information, education and cultural heritage communities. UKOLN was based at the University of Bath and was funded through a mixture of core and project grants. Latterly it received its core funding solely from JISC, but had received core grants previously from the Museums, Libraries and Archives Council and the British Library.
History
UKOLN traces its roots back to 1977, when Maurice Line initiated the Bath University Programme of Catalogue Research with funding from the British Library. This led to the establishment, in 1979, of a research centre under the directorship of Philip Bryant, again with British Library funding. It was known initially as the Centre for Catalogue Research, and later renamed the Centre for Bibliographic Management (CBM) to reflect its broadening research portfolio.
In 1989, the British Library established the UK Office for Library Networking to work alongside the CBM. It had one full-time member of staff. In 1992, it merged with the CBM and started to receive additional core funding from JISC. The combined organisation was known briefly as UKOLN: The Office for Library and Information Networking, but three years later this was simplified to the UK Office for Library and Information Networking. In 2002 it became known simply as UKOLN, again reflecting a shift in the focus of its activity.
In 1994, Lorcan Dempsey succeeded Philip Bryant as Director of UKOLN. He in turn was succeeded in the role by Liz Lyon in 2000.
In May 2013 an article published in the Times Higher Education announced that "16 of its 24 University of Bath-based staff [were made] redundant after the cessation of a £622,000 annual grant from the higher education technology body Jisc".
Although UKOLN continued after 31 July 2013 it was significantly reduced in size and was no longer working in many of the areas which were responsible for its visibility in national and international arenas. UKOLN's Director departed without replacement in late 2013. The remaining staff were made redundant or redeployed in July 2015, marking the cessation of UKOLN's activities.
Work
UKOLN's main work included:
influencing policy and informing practice;
promoting community-building and consensus making by actively raising awareness;
advancing knowledge through research and development;
building innovative systems and services based on Web technologies;
acting as an agent for knowledge transfer.
Its specialist areas included metadata, interoperability and digital curation. It was involved in a range of national and international projects including the DELOS Network of Excellence in Digital Libraries, the Development of a European Service for Information on Research and Education (DESIRE), the Digital Repository Infrastructure Vision for European Research (DRIVER, a precursor |
https://en.wikipedia.org/wiki/Network%20Solutions | Network Solutions, LLC is an American-based technology company and a subsidiary of Web.com, the 4th largest .com domain name registrar with over 6.7 million registrations as of August 2018. In addition to being a domain name registrar, Network Solutions provides web services such as web hosting, website design and online marketing, including search engine optimization and pay per click management.
History
Network Solutions started as a technology consulting company incorporated by Emmit McHenry with Ty Grigsby, Gary Desler and Ed Peters in Washington, D.C., in 1979.
In its first few years, the company focused on systems programming services, primarily in the IBM environment. Annual revenues passed $1 million in 1982, growing to $18.5 million in 1986.
Network Solutions, Inc. (NSI) first operated the domain name system (DNS) registry under a sub-contract with the U.S. Defense Information Systems Agency (DISA) in September 1991. NSI gave out names in the .com, .org, .mil, .gov, .edu and .net Top Level Domains (TLDs) for free, along with free Internet Protocol (IP) address blocks.
The Network Information Center at SRI International had performed the work under Elizabeth J. Feinler since 1972.
In 1992, NSI was the sole bidder on a grant from the National Science Foundation (NSF) to further develop the domain name registration service for the Internet. In 1993, NSI was granted an exclusive contract by the NSF to be the sole domain name registrar for .com (commerce), .net (network) and .org (organization) TLDs, a continuation of work NSI had already been doing. NSI also maintained the central database of assigned names called WHOIS. A contract was given to Boeing to operate the .mil TLD registry, and was also performed by NSI under subcontract.
In May 1993, the NSF privatized the domain name registry; Network Solutions was the only bidder on the $5.9 million annual contract to administer it.
In March 1995, the company was acquired by Science Applications International Corporation (SAIC) for $4.7 million. At that time, the company managed 60,000 domain names.
Following the acquisition by SAIC, the NSF gave Network Solutions authority to charge for domain name registrations. Network Solutions imposed a charge of $100 for two years registration. 30% of this revenue went to the NSF to create an "Internet Intellectual Infrastructure Fund." In 1997, a lawsuit was filed charging Network Solutions with antitrust violations with regard to domain names. The 30% of the registration fee that went to the NSF was ruled by a court to be an illegal tax. This led to a reduction in the domain name registration fee to $70 (for two years).
Network Solutions also implemented a policy of censoring domain names. This came to light when Jeff Gold attempted to register the domain name shitakemushrooms.com but was unable to. Network Solutions' automated screening system blocked the registration "because it contains four letters they consider obscene", though the domain |
https://en.wikipedia.org/wiki/Trial%20division | Trial division is the most laborious but easiest to understand of the integer factorization algorithms. The essential idea behind trial division tests to see if an integer n, the integer to be factored, can be divided by each number in turn that is less than n. For example, for the integer , the only numbers that divide it are 1, 2, 3, 4, 6, 12. Selecting only the largest powers of primes in this list gives that .
Trial division was first described by Fibonacci in his book Liber Abaci (1202).
Method
Given an integer n (n refers to "the integer to be factored"), the trial division consists of systematically testing whether n is divisible by any smaller number. Clearly, it is only worthwhile to test candidate factors less than n, and in order from two upwards because an arbitrary n is more likely to be divisible by two than by three, and so on. With this ordering, there is no point in testing for divisibility by four if the number has already been determined not divisible by two, and so on for three and any multiple of three, etc. Therefore, the effort can be reduced by selecting only prime numbers as candidate factors. Furthermore, the trial factors need go no further than because, if n is divisible by some number p, then n = p × q and if q were smaller than p, n would have been detected earlier as being divisible by q or by a prime factor of q.
A definite bound on the prime factors is possible. Suppose is the 'th prime, so that P1 = 2, P2 = 3, P3 = 5, etc. Then the last prime number worth testing as a possible factor of n is where ; equality here would mean that is a factor. Thus, testing with 2, 3, and 5 suffices up to n = 48 not just 25 because the square of the next prime is 49, and below n = 25 just 2 and 3 are sufficient. Should the square root of n be an integer, then it is a factor and n is a perfect square.
An example of the trial division algorithm, using successive integers as trial factors, is as follows (in Python):
def trial_division(n: int) -> list[int]:
"""Return a list of the prime factors for a natural number."""
a = [] # Prepare an empty list.
f = 2 # The first possible factor.
while n > 1: # While n still has remaining factors...
if n % f == 0: # The remainder of n divided by f might be zero.
a.append(f) # If so, it divides n. Add f to the list.
n //= f # Divide that factor out of n.
else: # But if f is not a factor of n,
f += 1 # Add one to f and try again.
return a # Prime factors may be repeated: 12 factors to 2,2,3.
Or 2x more efficient:
def trial_division(n: int) -> list[int]:
a = []
while n % 2 == 0:
a.append(2)
n //= 2
f = 3
while f * f <= n:
if n % f == 0:
a.append(f)
n //= f
else:
f += 2
if n != 1: a.append(n)
# Only odd number is poss |
https://en.wikipedia.org/wiki/Macintosh%20Programmer%27s%20Workshop | Macintosh Programmer's Workshop (MPW) is a software development environment for the Classic Mac OS operating system, written by Apple Computer. For Macintosh developers, it was one of the primary tools for building applications for System 7.x and Mac OS 8.x and 9.x. Initially MPW was available for purchase as part of Apple's professional developers program, but Apple made it a free download after it was superseded by CodeWarrior. On Mac OS X it was replaced by the Project Builder IDE, which eventually became Xcode.
Design
MPW provided a command line environment and tools, including 68k and PowerPC assemblers as well as Pascal, C and C++ compilers. The shell environment is somewhat similar to Unix shells in design, but is designed around the Macintosh's character set and GUI, replacing the usual terminal environment with a "worksheet" interface, allowing the user to select and run arbitrary sections of a shell script or to redo commands with no retyping. In addition, command line tools were commonly provided with a somewhat standardized graphical interface named Commando that provided limited access to the command line capabilities of the program. The debuggers were not integrated into MPW like most IDEs of today but the language compilers supported the symbolic debugging information file format used by the debugger. MPW supported a source-level debugger called SADE (Symbolic Application Debugging Environment). SADE was not an MPW Tool, but ran as a separate application with a user interface similar to MPW.
Apple's compilers had some features that were not common on other platforms—for example, the Pascal compiler was object-oriented, while the C and C++ compilers included support for length-prefixed strings (needed for Pascal-oriented APIs).
Pascal was Apple's original preferred language for Macintosh software development, and MPW was initially released with only Pascal support. A C compiler was released with MPW 2.0. The MPW C compiler was written under contract for Apple by Greenhills, a Macintosh-variant of the Green Hills C compiler designed specially for Apple and which was similar to the version that was available for the Lisa Workshop. In addition, the original MPW C compiler was known for its casual and frequently humorous error messages ("we already did this function"), as well as occasionally addressing users by name. These quirks were not carried on after the PowerPC transition, when Apple replaced the originals with compilers written by Symantec. Pascal support was no longer provided by the mid-90s due to declining popularity of the language.
MPW was always targeted to a professional audience and was seldom used by hobbyist developers due to the considerable price for the package; by the time it was made freeware it had long since been superseded by offerings from Symantec and Metrowerks, as well as Apple's own development tools inherited from NeXT and distributed for free with OS X. It was also occasionally available as a wrapp |
https://en.wikipedia.org/wiki/Dendral | Dendral was a project in artificial intelligence (AI) of the 1960s, and the computer software expert system that it produced. Its primary aim was to study hypothesis formation and discovery in science. For that, a specific task in science was chosen: help organic chemists in identifying unknown organic molecules, by analyzing their mass spectra and using knowledge of chemistry. It was done at Stanford University by Edward Feigenbaum, Bruce G. Buchanan, Joshua Lederberg, and Carl Djerassi, along with a team of highly creative research associates and students. It began in 1965 and spans approximately half the history of AI research.
The software program Dendral is considered the first expert system because it automated the decision-making process and problem-solving behavior of organic chemists. The project consisted of research on two main programs Heuristic Dendral and Meta-Dendral, and several sub-programs. It was written in the Lisp programming language, which was considered the language of AI because of its flexibility.
Many systems were derived from Dendral, including MYCIN, MOLGEN, PROSPECTOR, XCON, and STEAMER. There are many other programs today for solving the mass spectrometry inverse problem, see List of mass spectrometry software, but they are no longer described as 'artificial intelligence', just as structure searchers.
The name Dendral is an acronym of the term "Dendritic Algorithm".
Heuristic Dendral
Heuristic Dendral is a program that uses mass spectra or other experimental data together with a knowledge base of chemistry to produce a set of possible chemical structures that may be responsible for producing the data. A mass spectrum of a compound is produced by a mass spectrometer, and is used to determine its molecular weight, the sum of the masses of its atomic constituents. For example, the compound water (H2O), has a molecular weight of 18 since hydrogen has a mass of 1.01 and oxygen 16.00, and its mass spectrum has a peak at 18 units. Heuristic Dendral would use this input mass and the knowledge of atomic mass numbers and valence rules, to determine the possible combinations of atomic constituents whose mass would add up to 18. As the weight increases and the molecules become more complex, the number of possible compounds increases drastically. Thus, a program that is able to reduce this number of candidate solutions through the process of hypothesis formation is essential.
New graph-theoretic algorithms were invented by Lederberg, Harold Brown, and others that generate all graphs with a specified set of nodes and connection-types (chemical atoms and bonds) -- with or without cycles. Moreover, the team was able to prove mathematically that the generator is complete, in that it produces all graphs with the specified nodes and edges, and that it is non-redundant, in that the output contains no equivalent graphs (e.g., mirror images). The CONGEN program, as it became known, was developed largely by computational |
https://en.wikipedia.org/wiki/Graph%20%28abstract%20data%20type%29 | In computer science, a graph is an abstract data type that is meant to implement the undirected graph and directed graph concepts from the field of graph theory within mathematics.
A graph data structure consists of a finite (and possibly mutable) set of vertices (also called nodes or points), together with a set of unordered pairs of these vertices for an undirected graph or a set of ordered pairs for a directed graph. These pairs are known as edges (also called links or lines), and for a directed graph are also known as edges but also sometimes arrows or arcs. The vertices may be part of the graph structure, or may be external entities represented by integer indices or references.
A graph data structure may also associate to each edge some edge value, such as a symbolic label or a numeric attribute (cost, capacity, length, etc.).
Operations
The basic operations provided by a graph data structure G usually include:
: tests whether there is an edge from the vertex x to the vertex y;
: lists all vertices y such that there is an edge from the vertex x to the vertex y;
: adds the vertex x, if it is not there;
: removes the vertex x, if it is there;
: adds the edge z from the vertex x to the vertex y, if it is not there;
: removes the edge from the vertex x to the vertex y, if it is there;
: returns the value associated with the vertex x;
: sets the value associated with the vertex x to v.
Structures that associate values to the edges usually also provide:
: returns the value associated with the edge (x, y);
: sets the value associated with the edge (x, y) to v.
Common data structures for graph representation
Adjacency list
Vertices are stored as records or objects, and every vertex stores a list of adjacent vertices. This data structure allows the storage of additional data on the vertices. Additional data can be stored if edges are also stored as objects, in which case each vertex stores its incident edges and each edge stores its incident vertices.
Adjacency matrix
A two-dimensional matrix, in which the rows represent source vertices and columns represent destination vertices. Data on edges and vertices must be stored externally. Only the cost for one edge can be stored between each pair of vertices.
Incidence matrix
A two-dimensional matrix, in which the rows represent the vertices and columns represent the edges. The entries indicate the incidence relation between the vertex at a row and edge at a column.
The following table gives the time complexity cost of performing various operations on graphs, for each of these representations, with |V| the number of vertices and |E| the number of edges. In the matrix representations, the entries encode the cost of following an edge. The cost of edges that are not present are assumed to be ∞.
Adjacency lists are generally preferred for the representation of sparse graphs, while an adjacency matrix is preferred if the graph is dense; that is, the number of edges |E| is close to the nu |
https://en.wikipedia.org/wiki/Francisco%20Javier%20Zald%C3%BAa | Francisco Javier Martínez de Zaldúa y Racines was a Colombian, lawyer and politician, elected President of Colombia in 1882.
Biographic data
Zaldúa was born in Bogotá, Cundinamarca, on December 3, 1811. He died in the same city, in the Government Palace, on December 21, 1882. He was the first Colombian President to die while in office.
Early life
His father was don Manuel Maria Zaldúa, a prominent member of the Nueva Granada high society and a very wealthy man. He donated most of his fortune to the cause of independence and in particular to General Antonio Nariño. When the Spanish "Pacificador", General Pablo Morillo, made his triumphant entry in Bogotá, the Zaldúa family was attending the military parade. Zaldúa's father was so offended and outraged, that he suffered a massive heart attack and died instantly.
Zaldúa studied jurisprudence and theology at the "Colegio Mayor de San Bartolomé", where he graduated with a double mayor and obtained diplomas in Law and Divinity.
Professional career
Zaldúa was a professor of Civil Law and Canonical Law between 1837 and 1866. He later entered the judicial branch where he advanced all the way to Justice of the Supreme Court. As President of this legislative body, Zaldúa became the de facto President of the United States of Colombia for 6 days, when President Tomás Cipriano de Mosquera ceded executive power to the convention, and until the said convention elected a Council of Ministers to serve collectively as the Colombian head of state.
Political career
Zaldúa initiated his political career by being elected to the City Council of Bogotá. In 1840 he was elected to the House of Representatives and, later to the Senate, both in representation of his native state of Cundinamarca. He was also appointed as Minister of Government during the administration of President José Hilario López.
Zaldúa served as President of the Rionegro Convention, a constituent assembly that created the United States of Colombia, now the Republic of Colombia.
Presidency
In 1881, the presidential campaign to succeed the conservative President Rafael Núñez was taking place. Zaldúa was a man of immense prestige and reputation and José María Rojas Garrido nominated him as candidate for the presidency. The Colombian Liberal Party, which had been divided for many years, united around his name.
Zaldúa was 71 years old by then. Former president Aquileo Parra led the convention's commission that went to his home to request his acceptance. Zaldúa, in his acceptance speech said: “In the sunset of my life, I have nothing else to offer to the liberal party, but my last days. I hereby accept this nomination as my death sentence”. The Conservative Party abstained from the elections, and Zaldúa defeated fellow Liberal Solón Wilches. He was inaugurated on April 1, 1882.
Notes
References
1811 births
1882 deaths
Politicians from Bogotá
Presidential Designates of Colombia
Colombian people of Basque descent
Colombian Liberal Party politic |
https://en.wikipedia.org/wiki/Metaclass | In object-oriented programming, a metaclass is a class whose instances are also classes. Just as an ordinary class defines the behavior of certain objects, a metaclass defines the behavior of certain classes and their instances. Not all object-oriented programming languages support metaclasses. Among those that do, the extent to which metaclasses can override any given aspect of class behavior varies. Metaclasses can be implemented by having classes be first-class citizens, in which case a metaclass is simply an object that constructs classes. Each language has its own metaobject protocol, a set of rules that govern how objects, classes, and metaclasses interact.
Python example
In Python, the builtin class type is a metaclass. Consider this simple Python class:
class Car:
def __init__(self, make: str, model: str, year: int, color: str):
self.make = make
self.model = model
self.year = year
self.color = color
@property
def description(self) -> str:
"""Return a description of this car."""
return f"{self.color} {self.make} {self.model}"
At run time, Car itself is an instance of type. The source code of the Car class, shown above, does not include such details as the size in bytes of Car objects, their binary layout in memory, how they are allocated, that the __init__ method is automatically called each time a Car is created, and so on. These details come into play not only when a new Car object is created, but also each time any attribute of a Car is accessed. In languages without metaclasses, these details are defined by the language specification and can't be overridden. In Python, the metaclass - type - controls these details of Car's behavior. They can be overridden by using a different metaclass instead of type.
The above example contains some redundant code to do with the four attributes make, model, year, and color. It is possible to eliminate some of this redundancy using a custom metaclass. In Python, a metaclass is most easily defined as a subclass of type.
class AttributeInitType(type):
def __call__(self, *args, **kwargs):
"""Create a new instance."""
# First, create the object in the normal default way.
obj = type.__call__(self, *args)
# Additionally, set attributes on the new object.
for name, value in kwargs.items():
setattr(obj, name, value)
# Return the new object.
return obj
This metaclass only overrides object creation. All other aspects of class and object behavior are still handled by type.
Now the class Car can be rewritten to use this metaclass. In Python 3 this is done by providing a "keyword argument" metaclass to the class definition:
class Car(object, metaclass=AttributeInitType):
@property
def description(self) -> str:
"""Return a description of this car."""
return " ".join(str(value) for value in self.__dict__.values())
The resulting object Car can be instant |
https://en.wikipedia.org/wiki/Steve%20Grand%20%28roboticist%29 | Steve Grand OBE (born 12 February 1958) is a British computer scientist and roboticist. He was the creator and lead programmer of the Creatures artificial life simulation, which he discussed in his first book Creation: Life and How to Make It, a finalist for the 2001 Aventis Prize for Science Books. He is also an Officer of the Most Excellent Order of the British Empire, which he received in 2000.
Grand's project from 2001 to 2006 was the building of an artificial robot baby orangutan, with the intention of having it learn as a human baby would. This is documented in his book Growing up with Lucy.
Projects
Creatures
One of the best known projects created by Steve Grand is Creatures, an artificial life simulation, which his company Cyberlife released in 1996.
Lucy, the Android
His project from 2001 to 2005 was Lucy, a mechanical baby orangutan. Lucy was an attempt at simulating the mind of a human baby.
Sim-biosis
Grand worked on Sim-biosis, a computer simulation game in which complete artificial creatures could be built from functional, structural units. It is available on SourceForge under the name Simergy.
Grandroids
In February 2011, Grand announced a new project, Grandroids, described as "real 'alien' life forms who can live in a virtual world on your computer".
Bibliography
Creation: Life and How to Make It (2001)
Growing Up with Lucy (2004)
What is the Secret of Consciousness? (2014) TEDxOporto presentation
References
External links
Transcript of Steve's keynote speech, "Machines Like Us," given at the Applied Knowledge Research Institute's 2002 Biennial Seminar
Steve Grand at the Creatures Wiki
Feature article on Steve Grand's anthropoid orangutan, Lucy
Steve Grand quotes
Steve Grand's discussion with Johnjoe McFadden
Cyberlife Research Limited
Steve Grand's Machines Like Us interview
Grandroids: Real artificial life on your PC a project by Steve Grand
1958 births
Artificial intelligence researchers
British roboticists
Creatures (video game series)
English computer scientists
Living people
Officers of the Order of the British Empire
Researchers of artificial life |
https://en.wikipedia.org/wiki/Entrez | The Entrez () Global Query Cross-Database Search System is a federated search engine, or web portal that allows users to search many discrete health sciences databases at the National Center for Biotechnology Information (NCBI) website. The NCBI is a part of the National Library of Medicine (NLM), which is itself a department of the National Institutes of Health (NIH), which in turn is a part of the United States Department of Health and Human Services. The name "Entrez" (a greeting meaning "Come in" in French) was chosen to reflect the spirit of welcoming the public to search the content available from the NLM.
Entrez Global Query is an integrated search and retrieval system that provides access to all databases simultaneously with a single query string and user interface. Entrez can efficiently retrieve related sequences, structures, and references. The Entrez system can provide views of gene and protein sequences and chromosome maps. Some textbooks are also available online through the Entrez system.
Features
The Entrez front page provides, by default, access to the global query. All databases indexed by Entrez can be searched via a single query string, supporting Boolean operators and search term tags to limit parts of the search statement to particular fields. This returns a unified results page, that shows the number of hits for the search in each of the databases, which are also linked to actual search results for that particular database.
Entrez also provides a similar interface for searching each particular database and for refining search results. The Limits feature allows the user to narrow a search, a web forms interface. The History feature gives a numbered list of recently performed queries. Results of previous queries can be referred to by number and combined via Boolean operators. Search results can be saved temporarily in a Clipboard. Users with a MyNCBI account can save queries indefinitely, and also choose to have updates with new search results e-mailed for saved queries of most databases. It is widely used in the field of biotechnology as a reference tool for students and professionals alike.
Databases
Entrez searches the following databases:
PubMed: biomedical literature citations and abstracts, including Medline - articles from (mainly medical) journals, often including abstracts. Links to PubMed Central and other full-text resources are provided for articles from the 1990s.
PubMed Central: free, full-text journal articles
Site Search: NCBI web and FTP web sites
Books: online books
Online Mendelian Inheritance in Man (OMIM)
Nucleotide: sequence database (GenBank)
Protein: sequence database (GenPept)
Genome: whole genome sequences and mapping
Structure: three-dimensional macromolecular structures
Taxonomy: organisms in GenBank Taxonomy
dbSNP: single nucleotide polymorphism
Gene: gene-centered information
HomoloGene: eukaryotic homology groups
PubChem Compound: unique small molecule chemical structures
PubChem |
https://en.wikipedia.org/wiki/CML | CML may refer to:
Computing
Chemical Markup Language, a representation of chemistry using XML
Column Managed Lengths, a representation of data in columns
Concurrent Mapping and Localization, a technique for building and utilizing maps by autonomous robots
Concurrent ML, a high-level language for concurrent programming
Configuration Menu Language, a language and system for compiling the Linux kernel
Conversation Markup Language, a language for building chatbots
Coupled Map Lattices, an extended method of cellular automaton
Electronics
Current mode logic, a differential digital logic family
Commercial microwave link, a communication channel between neighbouring towers in mobile networks
Organizations
Centre for Missional Leadership, the Watford campus of the London School of Theology
Cinematography Mailing List, a long established and renowned website for professional cinematographers
Classical Marimba League, an organization promoting the marimba, a percussion instrument
CML - Institute of Environmental Sciences, an institute at Leiden University - the Netherlands
Colorado Municipal League, see NLC members
Columbus Metropolitan Library, one of the most used library systems in the United States
Corpul Muncitoresc Legionar, a Romanian fascist workers' association
Council of Mortgage Lenders, a trade association for the British mortgage lending industry
Science and medicine
Chronic myelogenous leukemia, a blood cancer
N(6)-Carboxymethyllysine, an advanced glycation end-product
Other uses
Camarillo (Amtrak station) (station code CML), a train station in California, United States
Chiltern Main Line
Capital market line, the result when the market portfolio is combined with the risk-free asset
Certified Master Locksmith, as awarded by the Associated Locksmiths of America
950 in Roman numerals
Camooweal Airport, IATA airport code "CML"
See also
A common mistyping of XML in computing |
https://en.wikipedia.org/wiki/Backtick | The backtick is a typographical mark used mainly in computing. It is also known as backquote, grave, or grave accent.
The character was designed for typewriters to add a grave accent to a (lower-case) base letter, by overtyping it atop that letter. On early computer systems, however, this physical dead key+overtype function was rarely supported, being functionally replaced by precomposed characters. Consequently, this ASCII symbol was rarely (if ever) used in computer systems for its original aim and became repurposed for many unrelated uses in computer programming.
The sign is located on the left-top of a US or UK layout keyboard, next to the key. On older keyboards, the Escape key was at this location, and the backtick key was somewhere on the right side of the layout. Provision (if any) of the backtick on other keyboards varies by national keyboard layout and keyboard mapping.
History
Typewriters
On typewriters designed for languages that routinely use diacritics (accent marks), there are two possible solutions. Keys can be dedicated to pre-composed characters or alternatively a dead key mechanism can be provided. With the latter, a mark is made when a dead key is typed but, unlike normal keys, the paper carriage does not move on and thus, the next letter to be typed is printed under the accent.
Incorporation into ISO 646 and ASCII
The incorporation of the grave symbol into ASCII is a consequence of this prior existence on typewriters. This symbol did not exist independently as a type or hot-lead printing character.
Thus, ISO646 was born and the ASCII standard updated to include the backtick and other symbols.
As surrogate of apostrophe or (opening) single quote
Some early typewriters and ASCII peripherals designed the backtick and apostrophe to be mirror images of each other. This allowed them to be used as matching pairs of open and close quotes, and also as grave and acute accents, and allowed the apostrophe to be used as a prime. None of these were considered typographically correct.
The use of apostrophe for opening quotes, the need on some typewriters to overprint apostrophe and period to get an exclamation mark, and the lack of a mirrored double-quote character, tended to change the apostrophe to the modern "typewriter" design that is vertical, so this no longer works. Unicode now provides separate characters for opening and closing quotes.
Such style is sometimes used even nowadays; examples are: output generated by some UNIX console programs, rendering of man pages within some environments, technical documentation written long ago or written in old-school manner. However, as time goes on, such style is used less and less, and even institutions that traditionally were using that style are now abandoning it.
Computing
Command-line interface languages
Many command-line interface languages and the scripting (programming) languages like Perl, PHP, Ruby and Julia (though see below) use pairs of backticks to indicate command |
https://en.wikipedia.org/wiki/BioJava | BioJava is an open-source software project dedicated to provide Java tools to process biological data. BioJava is a set of library functions written in the programming language Java for manipulating sequences, protein structures, file parsers, Common Object Request Broker Architecture (CORBA) interoperability, Distributed Annotation System (DAS), access to AceDB, dynamic programming, and simple statistical routines. BioJava supports a huge range of data, starting from DNA and protein sequences to the level of 3D protein structures. The BioJava libraries are useful for automating many daily and mundane bioinformatics tasks such as to parsing a Protein Data Bank (PDB) file, interacting with Jmol and many more. This application programming interface (API) provides various file parsers, data models and algorithms to facilitate working with the standard data formats and enables rapid application development and analysis.
Additional projects from BioJava include rcsb-sequenceviewer, biojava-http, biojava-spark, and rcsb-viewers.
Features
BioJava provides software modules for many of the typical tasks of bioinformatics programming. These include:
Accessing nucleotide and peptide sequence data from local and remote databases
Transforming formats of database/ file records
Protein structure parsing and manipulation
Manipulating individual sequences
Searching for similar sequences
Creating and manipulating sequence alignments
History and publications
The BioJava project grew out of work by Thomas Down and Matthew Pocock to create an API to simplify development of Java-based Bioinformatics tools. BioJava is an active open source project that has been developed over more than 12 years and by more than 60 developers. BioJava is one of a number of Bio* projects designed to reduce code duplication. Examples of such projects that fall under Bio* apart from BioJava are BioPython, BioPerl, BioRuby, EMBOSS etc.
In October 2012, the first paper on BioJava was published. This paper detailed BioJava's modules, functionalities, and purpose.
As of November 2018 Google Scholar counts more than 130 citations.
The most recent paper on BioJava was written in February 2017. This paper detailed a new tool named BioJava-ModFinder. This tool can be used for identification and subsequent mapping of protein modifications to 3D in the Protein Data Bank (PBD). The package was also integrated with the RCSB PDB web application and added protein modification annotations to the sequence diagram and structure display. More than 30,000 structures with protein modifications were identified by using BioJava-ModFinder and can be found on the RCSB PDB website.
In the year 2008, BioJava's first Application note was published. It was migrated from its original CVS repository to GitHub in April 2013. The project has been moved to a separate repository, BioJava-legacy, and is still maintained for minor changes and bug fixes.
Version 3 was released in December 2010. It was a major |
https://en.wikipedia.org/wiki/Open%20Bioinformatics%20Foundation | The Open Bioinformatics Foundation is a non-profit, volunteer-run organization focused on supporting open source programming in bioinformatics. The mission of the foundation is to support the development of open source toolkits for bioinformatics, organise developer-centric hackathon events and generally assist in the development and promotion of open source software development in the life sciences. The foundation also organises and runs the annual Bioinformatics Open Source Conference, a satellite meeting of the Intelligent Systems for Molecular Biology conference. The foundation participates in the Google Summer of Code, acting as an umbrella organisation for individual bioinformatics-related projects.
The Open Bioinformatics Foundation was started in 2001, arising from the BioJava, BioPerl and BioPython projects. A formal membership for the foundation was created in 2005. In October 2012, the foundation began an association with Software in the Public Interest (SPI), a US-based non-profit which aids other organizations in the creation and distribution of free and open-source software. The association with SPI allows financial donations to the foundation (these are 501(c)3 tax-exempt in the US).
The foundation is governed by a board of directors, representing various Bio* projects. As of 2019, the OBF President is Peter Cock (BioPython). Previous OBF presidents include Ewan Birney and Hilmar Lapp (NESCent), previous Board members include Steven E. Brenner.
Projects
The foundation hosts servers for mailing lists, websites, and code repositories for a number of bioinformatics-related open source projects, including:
BioJava – Java toolkit
BioMOBY – Data and application execution through web services
BioPerl – Perl toolkit
BioPython – Python toolkit
BioRuby – Ruby toolkit
BioPHP
EMBOSS – Sequence analysis toolkit.
See also
List of open-source bioinformatics software
Generic Model Organism Database
References
External links
Open Bioinformatics Foundation website
Bioinformatics organizations
Free software project foundations |
https://en.wikipedia.org/wiki/WXGA | WXGA may refer to:
Wide Extended Graphics Array, a computer graphics display resolution
WXGA-TV, a television station in the U.S. state of Georgia |
https://en.wikipedia.org/wiki/ATASCII | The ATASCII character set, from ATARI Standard Code for Information Interchange, alternatively ATARI ASCII, is the variation on ASCII used in the Atari 8-bit family of home computers. The first of this family are the Atari 400 and 800, released in 1979, and later models were released throughout the 1980s. The last computer to use the ATASCII character set is the Atari XEGS which was released in 1987 and discontinued in 1992. The Atari ST family of computers use the different Atari ST character set.
Like most other non-standard ASCIIs, ATASCII has its own special block graphics symbols (arrows, blocks, circles, line segments, playing card suits, etc.) corresponding to the control character locations of the standard ASCII table (characters 0–31), and a few other character locations.
Control characters
The main difference between standard ASCII and ATASCII is the use of control characters. In standard ASCII, a character in the range 0 to 31 is construed as a command, which might move the cursor, clear the screen, end a line, and so on. Some of these were designed for use on printers and teletypes rather than on screen (to advance the paper, overtype, and so on). In ATASCII most of the ASCII control character values produce a graphics glyph instead. ATASCII uses character values different from ASCII for cursor control.
ATASCII has a character set of only 128 characters. If the high-order bit is set on a character (i.e., if the byte value of the character is between 128 and 255) the character is generally rendered in the reverse video (also called "inverse video") of its counterpart between 0 and 127, using a bitwise negation of the character's glyph. This is done by the ANTIC chip. The two exceptions to this rule are that an "escape" character (ATASCII and ASCII 27) with its high order bit set becomes an "EOL" or "End Of Line" character (ATASCII 155; ASCII 13), and a "clear screen" character (ATASCII 125) with its high order bit set becomes a "bell" or "buzzer" character (ATASCII 253; ASCII 7).
The ATASCII control characters used by the screen editor for cursor control (arrow keys) and text editing (tab, insert, delete, backspace, etc.) have associated graphic symbols that can be displayed by preceding them by the "escape" character (ATASCII 27). For example, a right arrow can be displayed on a screen or printer by preceding it with the escape character followed by the "cursor right" character itself (ATASCII 31).
The Atari screen editor implements the text cursor by simply inverting the character at the cursor position (by XOR with $80). It does not flash.
Interoperation
The differences between character representation can cause problems during modem communication between Ataris and other computers. Cursor movement commands (and even carriage returns and line feeds) from computers not using ATASCII will be nonsense on an Atari, and vice versa. Terminal programs need to translate between ATASCII and standard ASCII.
Some Atari-based BBSs ex |
https://en.wikipedia.org/wiki/CHWI-DT | CHWI-DT (channel 16) is a television station licensed to Wheatley, Ontario, Canada, broadcasting CTV 2 programming to the Windsor area. Owned and operated by Bell Media, the station has studios at the Bell Canada Building in downtown Windsor with a secondary office in Chatham; its transmitter is located on Zion Road (between Concession Line Roads 4 and 5) in Chatham.
History
Beginnings: independent and BBS
Baton Broadcasting applied to the Canadian Radio-television and Telecommunications Commission (CRTC) for a licence to operate an independent television station for the Wheatley area, that would also serve Chatham and Windsor. This application was related to, and directly dependent on, Baton's purchase of CFPL-TV in London and CKNX-TV in Wingham from The Blackburn Group, as their intention was to launch a semi-satellite of CFPL-TV that served Chatham and Windsor. At the time, the only clear signals from Canadian stations were from TVOntario, the CBC and Télévision de Radio-Canada. The station's license application was approved on January 26, 1993, and CHWI-TV first began broadcasting on October 19, 1993. This marked Baton's return to television broadcasting in the region after the CBC had bought out Baton's majority interest in CKLW-TV in Windsor, renaming it CBET, in 1975 (Baton also operated radio stations in Windsor until 1984).
During its tenure as an independent station, it also aired ABC's Disney's One Saturday Morning schedule (along with, or from, the CTV affiliate in Kitchener, CKCO-TV), along with syndicated Disney shows in the afternoons on weekdays (The Disney Afternoon), such as Bonkers and Goof Troop before the 5 p.m. news, similar to WXON (channel 20, now WMYD) and WKBD-TV (channel 50, now a CW owned-and-operated station) across the river in Detroit. While the station aired many CTV programs, it was never branded as a CTV station directly, but it was labelled as a BBS station instead. For all intents and purposes, it was Windsor's CTV affiliate for most of this time, if in programming and not by affiliation or name. Windsor is one of the few major Canadian cities that has never had a CTV affiliate of its own, largely because CTV owns the Canadian rights to a large amount of American programming. The Windsor area is considered part of the Detroit market for purposes of programming rights, and Windsor stations have often had to adjust their coverage or programming under pressure from the Detroit stations. CTV programming is piped in via CKCO on basic cable; that station's Sarnia-area translator was the nearest over-the-air source of CTV programming until it was shut down in May 2020.
It was broadcast on channel 16 only (its Wheatley transmitter) for the first two years. However, the transmitter was located farther to the southeast, presumably to protect the Detroit stations. As a result, it was practically unviewable over-the-air in Windsor.
In response to complaints from the Windsor area, Baton applied for a Windsor-area trans |
https://en.wikipedia.org/wiki/Zendstation%20Smilde | Zendstation Smilde, also known as the CJ2 Data tower (Dutch: CJ2 Datatoren) is a tall partially guyed tower in Hoogersmilde, the Netherlands, built in 1959, for directional radio services and TV and FM-transmissions. The structure is similar to the Gerbrandy Tower (IJsselstein), and consists of an 80-metre (262') high reinforced concrete tower and, until a fire on 15 July 2011, had a guyed tubular mast mounted on top. When first built, the tower, including the mast, was 270 metres (885') high. The addition of a further section (analog TV - UHF antenna) to the mast increased its total height to 303.5 metres (996 ft).
In September 2007 the analog TV - UHF antenna was removed and replaced by a new UHF antenna for DVB-T, reducing the tower's height to 294 metres (965 ft). After rebuilding the collapsed tower in 2012, the new height is 303 metres (995').
Owner
Originally the mast was built by the state company for Post and Telephony (Koninklijke KPN N.V.) but due to privatisation this has changed. Several masts in The Netherlands, including above mentioned Gerbrandy Tower, have a complex ownership structure:
The 82 metre (270') high concrete tower is owned by Alticom BV
The steel mast on top of the concrete tower is owned by NOVEC BV, a 100% daughter of TenneT BV, which is itself 100% state-owned
The grounds on which the mast is located is owned by KPN, except for a ring of 3 metres (10') around the base of the tower which is owned by Alticom.
Aircraft incident
On 14 August 1968 a US Air Force plane, an F-100 Super Sabre, from the Lakenheath Air Force Base in England was involved in an accident in heavy low clouds where the tip of a wing hit and broke one of the guy-wires of the tower, causing the upper section of the tower to bend. The pilot made an emergency landing at Soesterberg Royal Netherlands Air Force Base with considerable damage to the right wing.
Fire and collapse
On 15 July 2011, the antenna section caught fire and collapsed, leaving only the concrete base standing.
In the above-mentioned report a warning was given that there was an increased risk of accidents in the masts, mainly because of the complex ownership structure and that because of that (safety) processes were unclear. An investigation by the Dutch police didn't show any (criminal) negligence or other factors that could have caused the fire.
Rebuilding the mast
The above fire destroyed the steel mast on top of the concrete tower completely and the top of the concrete tower (the base of the steel mast) was damaged. The owner of the steel mast, NOVEC BV, announced that starting in March 2012, the new mast will be placed on top of the concrete tower and that the new mast will be operational in the summer of 2012. The new mast will be a few metres (yards) higher than the destroyed one bringing the mast to the same height as before 2006, and will be a steel lattice construction instead of the original tube style. This will prevent the 'chimney effect', and thus safer i |
https://en.wikipedia.org/wiki/RealVNC | RealVNC is a company that provides remote access software. Their VNC Connect software consists of a server (VNC Server) and client (VNC Viewer) application, which exchange data over the RFB protocol to allow the Viewer to control the Server's screen remotely. The application is used, for example, by IT support engineers to provide helpdesk services to remote users.
History
Andy Harter and other members of the original VNC team at AT&T founded RealVNC Limited in 2002. The automotive division of RealVNC spun out as a separate company (VNC Automotive) in 2018.
Platforms, editions, versions
For a desktop-to-desktop connection RealVNC runs on Windows, macOS, and many Unix-like operating systems. A list of supported platforms can be found on the website. A RealVNC client also runs on the Java platform and on the Apple iPhone, iPod touch and iPad and Google Android devices.
A Windows-only client, VNC Viewer Plus was launched in 2010, designed to interface to the embedded server on Intel AMT chipsets found on Intel vPro motherboards. RealVNC removed VNC Viewer Plus from sale on 28th February 2021.
For remote access to view one computer desktop on another, RealVNC requires one of three subscriptions:
Home – free registration and activation required
Professional – commercial version geared towards home or small-business users, with authentication and encryption, remote printing, chat and file transfer
Enterprise – commercial version geared towards enterprises, with enhanced authentication and encryption, remote printing, chat, file transfer, and command-line deployment
As of release 4.3 (released August 2007), separate versions of both the Personal and Enterprise editions exist for 32-bit and 64-bit systems. Release 4.6 included features such as HTTP proxy support, chat, an address book, remote printing, unicode support, and connection notification.
Users must activate each of the server versions ("Home", "Professional", "Enterprise").
With the release of VNC 5.0 late December 2013, RealVNC software editions used a single binary which superseded VNC Enterprise Edition and VNC Personal Edition.
In November 2016, RealVNC released the updated version of their software, now called VNC Connect (version 6.0). The new version introduces a cloud connection option using a subscription-based pricing model. Users can choose between three subscription levels; Home (free for non-commercial use), Professional and Enterprise. Home and Professional subscriptions are cloud connections only. The Enterprise subscription supports hybrid connections that include the traditional direct (peer to peer) connections and/or cloud connections.
Client (VNC Viewer)
RealVNC clients using vncviewer can run in full-screen mode; they use the F8 function-key as the default key for bringing up an options menu (which includes the option to, among other things, switch off full screen mode or to forward a Control-Alt-Delete key-sequence).
Server (VNC Server)
The server component o |
https://en.wikipedia.org/wiki/Ol%27%20Yellow%20Eyes%20Is%20Back | Ol' Yellow Eyes Is Back is an album by Brent Spiner, best known for his role as Data in the American television series Star Trek: The Next Generation, first released in June 1991. The title is a parodic reference both to Frank Sinatra's Ol' Blue Eyes Is Back and the Data character, whose eyes are golden yellow. On the album, Spiner is backed by the orchestra from that series as he sings a number of old pop standards, mostly from the 1930s and 1940s.
Background
In the liner notes, Spiner wrote of Sinatra's "You Make Me Feel So Young":
Sinatra at his awesome best. This song and dozens of others accompanied every dinner I ate between the ages of five and thirteen. My stepfather, an amateur saxophone player and a hell of a mambo dancer, had put together one of the all time great collections of popular music recordings anywhere. So, to my good fortune, we dined each night with the likes of Ol' Blue Eyes, Judy Garland, Nat "King" Cole, Rosemary Clooney, Louis Prima and Keely Smith and every other singer that ever performed on Capitol, Decca or R.C.A. records.
Production
Spiner had help from a number of his colleagues from Star Trek: TNG. Wendy Neuss, associate producer for the series, and Dennis McCarthy, who scored the music for many of the episodes, co-produced the album with Spiner. Several fellow cast members (LeVar Burton, Michael Dorn, Jonathan Frakes, and Patrick Stewart) even joined him to sing "It's a Sin (To Tell a Lie)," appearing under the group name of "The Sunspots", a word play on The Ink Spots, the first group to perform this song. McCarthy praised the recording experience, and compared it to the time he spent earlier in his career on tour with Glen Campbell.
Release
According to Spiner, the album was released in Europe against his wishes after he had rejected attempts by the record company to renegotiate his contract.
Track listing
"Time After Time" (w. Sammy Cahn m. Jule Styne)
"The Very Thought of You" (w.m. Ray Noble)
"More Than You Know" (w. Edward Eliscu & Billy Rose m. Vincent Youmans)
"Toot Toot Tootsie" (w.m. Ted Fio Rito, Robert A. King, Gus Kahn & Ernie Erdman)
"Embraceable You" (w. Ira Gershwin m. George Gershwin)
"It's a Sin (To Tell a Lie)" (w.m. Billy Mayhew)
"Long, Long Time" (w. Sammy Cahn m. Jule Styne)
"Carolina in the Morning" (w. Gus Kahn m. Walter Donaldson)
"Marie" (Randy Newman)
"Zing! Went the Strings of My Heart" (w.m. James F. Hanley)
"When I Fall in Love" (w. Edward Heyman m. Victor Young)
"Goodnight, Sweetheart" (w.m. Ray Noble, Jimmy Campbell, Reg Connelly, adapted by Rudy Vallee)
Personnel
Brent Spiner: Lead vocals
The Sunspots: Back-up vocals for "It's a Sin (To Tell a Lie)"
LeVar Burton
Michael Dorn
Jonathan Frakes
Patrick Stewart
Ralph Humphrey: drums
Ken Wild: Bass
George Doering: Guitar
Jim Cox: Piano
John Kavanaugh: Piano
Bob O'Donnell: Trumpet
Bob Findley: Trumpet
John Rosenberg: Trumpet
Dick Hyde: Trombone
Lew McCreary: Trombone
Ernie Carlson: Trombone
Pete Christlieb: Woodwinds
Gene Cipriano |
https://en.wikipedia.org/wiki/Lucas%20critique | The Lucas critique argues that it is naive to try to predict the effects of a change in economic policy entirely on the basis of relationships observed in historical data, especially highly aggregated historical data. More formally, it states that the decision rules of Keynesian models—such as the consumption function—cannot be considered as structural in the sense of being invariant with respect to changes in government policy variables. It was named after American economist Robert Lucas's work on macroeconomic policymaking.
The Lucas critique is significant in the history of economic thought as a representative of the paradigm shift that occurred in macroeconomic theory in the 1970s towards attempts at establishing micro-foundations.
Thesis
The Lucas critique was not new in 1976. The argument and the whole logic was first presented by Frisch (1938) and discussed by Haavelmo (1944), among others. Related ideas are expressed as Campbell's law and Goodhart's law—but in a 1976 paper, Lucas drove to the point that this simple notion invalidated policy advice based on conclusions drawn from large-scale macroeconometric models. Because the parameters of those models were not structural, i.e. not policy-invariant, they would necessarily change whenever policy (the rules of the game) was changed. Policy conclusions based on those models would therefore potentially be misleading. This argument called into question the prevailing large-scale econometric models that lacked foundations in dynamic economic theory. Lucas summarized his critique:
Given that the structure of an econometric model consists of optimal decision rules of economic agents, and that optimal decision rules vary systematically with changes in the structure of series relevant to the decision maker, it follows that any change in policy will systematically alter the structure of econometric models.
The Lucas critique is, in essence, a negative result. It tells economists, primarily, how not to do economic analysis. The Lucas critique suggests that if we want to predict the effect of a policy experiment, we should model the "deep parameters" (relating to preferences, technology, and resource constraints) that are assumed to govern individual behavior: so-called "microfoundations." If these models can account for observed empirical regularities, we can then predict what individuals will do, taking into account the change in policy, and then aggregate the individual decisions to calculate the macroeconomic effects of the policy change.
Shortly after the publication of Lucas's article, Kydland and Prescott published the article "Rules rather than Discretion: The Inconsistency of Optimal Plans", where they not only described general structures where short-term benefits are negated in the future through changes in expectations, but also how time consistency might overcome such instances. That article and subsequent research led to a positive research program for how to do dynamic, quant |
https://en.wikipedia.org/wiki/Master%20theorem%20%28analysis%20of%20algorithms%29 | In the analysis of algorithms, the master theorem for divide-and-conquer recurrences provides an asymptotic analysis (using Big O notation) for recurrence relations of types that occur in the analysis of many divide and conquer algorithms. The approach was first presented by Jon Bentley, Dorothea Blostein (née Haken), and James B. Saxe in 1980, where it was described as a "unifying method" for solving such recurrences. The name "master theorem" was popularized by the widely-used algorithms textbook Introduction to Algorithms by Cormen, Leiserson, Rivest, and Stein.
Not all recurrence relations can be solved with the use of this theorem; its generalizations include the Akra–Bazzi method.
Introduction
Consider a problem that can be solved using a recursive algorithm such as the following:
procedure p(input x of size n):
if n < some constant k:
Solve x directly without recursion
else:
Create a subproblems of x, each having size n/b
Call procedure p recursively on each subproblem
Combine the results from the subproblems
The above algorithm divides the problem into a number of subproblems recursively, each subproblem being of size . Its solution tree has a node for each recursive call, with the children of that node being the other calls made from that call. The leaves of the tree are the base cases of the recursion, the subproblems (of size less than k) that do not recurse. The above example would have child nodes at each non-leaf node. Each node does an amount of work that corresponds to the size of the subproblem passed to that instance of the recursive call and given by . The total amount of work done by the entire algorithm is the sum of the work performed by all the nodes in the tree.
The runtime of an algorithm such as the above on an input of size , usually denoted , can be expressed by the recurrence relation
where is the time to create the subproblems and combine their results in the above procedure. This equation can be successively substituted into itself and expanded to obtain an expression for the total amount of work done. The master theorem allows many recurrence relations of this form to be converted to Θ-notation directly, without doing an expansion of the recursive relation.
Generic form
The master theorem always yields asymptotically tight bounds to recurrences from divide and conquer algorithms that partition an input into smaller subproblems of equal sizes, solve the subproblems recursively, and then combine the subproblem solutions to give a solution to the original problem. The time for such an algorithm can be expressed by adding the work that they perform at the top level of their recursion (to divide the problems into subproblems and then combine the subproblem solutions) together with the time made in the recursive calls of the algorithm. If denotes the total time for the algorithm on an input of size , and denotes the amount of time taken at the top level of |
https://en.wikipedia.org/wiki/Brandeis | Brandeis is a surname.
People
Antonietta Brandeis (1848–1926), Czech-born Italian painter
Brandeis Marshall, American data scientist
Friedl Dicker-Brandeis, Austrian artist and Holocaust victim
Irma Brandeis, American Dante scholar
Louis Brandeis, U.S. Supreme Court Justice
Named for Louis Brandeis
Brandeis University, in Massachusetts, U.S.
Brandeis-Bardin Institute, now the Brandeis-Bardin Campus of American Jewish University, in California, U.S.
Louis D. Brandeis School of Law, at the University of Louisville in Kentucky, U.S.
The Brandeis brief, a 1908 document written by Brandeis as a litigator
Brandeis Medal, awarded by the University of Louisville's Louis D. Brandeis Society
Brandeis Award (disambiguation), several different awards
Kfar Brandeis (English: Brandeis village), a suburb of Hadera, Israel
See also
Brandýs nad Labem-Stará Boleslav (), a town in the Czech Republic
Brandýs nad Orlicí (), a town in the Czech Republic
J. L. Brandeis and Sons Store, an Omaha, Nebraska-based department store chain
Brandeis Brokers, a broker on the London Metal Exchange
Brandys (disambiguation)
Brandis (surname)
Brandes (disambiguation)
German-language surnames |
https://en.wikipedia.org/wiki/GTL | GTL may refer to:
Organisations
GTL Ltd, an Indian network service provider
Georgia Tech Lorraine, a campus of the Georgia Institute of Technology in Metz, France
Glenvale Transport, an English bus company
Global Tel Link, an American telecommunications company
Groupe Tactique Lorraine, a French resistance force in World War II
Guntakal railway division (reporting mark), of Indian Railways
Guntakal Junction railway station (station code), Andhra Pradesh, India
Science and technology
Gas to liquids, a refinery process
Gunning transceiver logic, a type of logic signaling
Other uses
GT Legends, a video game
GTL (Grand Touring, Light); in motorsports, a 1980s light prototype (lesser than GTP) class of the IMSA GT Championship
See also
GTI (disambiguation)
GT1 (disambiguation) |
https://en.wikipedia.org/wiki/Yasumasa%20Kanada | was a Japanese computer scientist most known for his numerous world records over the past three decades for calculating digits of . He set the record 11 of the past 21 times.
Kanada was a professor in the Department of Information Science at the University of Tokyo in Tokyo, Japan until 2015.
From 2002 until 2009, Kanada held the world record calculating the number of digits in the decimal expansion of pi – exactly 1.2411 trillion digits. The calculation took more than 600 hours on 64 nodes of a HITACHI SR8000/MPP supercomputer. Some of his competitors in recent years include Jonathan and Peter Borwein and the Chudnovsky brothers.
See also
Chronology of computation of
References
External links
1949 births
2020 deaths
20th-century Japanese mathematicians
21st-century Japanese mathematicians
People from Himeji, Hyōgo
Pi-related people
Tohoku University alumni
Academic staff of the University of Tokyo |
https://en.wikipedia.org/wiki/Upsilon%20Pi%20Epsilon | Upsilon Pi Epsilon (): International Honor Society for the Computing and Information Disciplines, is the first honor society dedicated to the discipline of the computing and information disciplines. Informally known as UPE, Upsilon Pi Epsilon was founded on January 10, 1967 at Texas A&M University and has chartered over 270 chapters at college campuses around the world. With the rise of importance of information technology to many fields, other honorary societies have added computer science to their traditional scope.
About
Upsilon Pi Epsilon is endorsed by the Association for Computing Machinery (ACM) and the Institute of Electrical and Electronics Engineers Computer Society (IEEE-CS), the two largest computer organizations in the world. Aside from conferring honor on computer science and computer engineering students, it has a large involvement with the ACM International Collegiate Programming Contest. UPE is a member of the ACHS - Association of College Honor Societies.
Membership in UPE, like many other honor societies, is lifetime. Newly inducted student members get a free year of ACM student-level membership as well. Additionally, UPE gives out a number of scholarships for its members and those who are active student members of the ACM or IEEE-CS.
References
External links
UPE Homepage
ACHS Upsilon Pi Epsilon entry
Upsilon Pi Epsilon chapter list at ACHS
Association of College Honor Societies
Honor societies
Student organizations established in 1967
1967 establishments in Texas |
https://en.wikipedia.org/wiki/Sorting%20network | In computer science, comparator networks are abstract devices built up of a fixed number of "wires", carrying values, and comparator modules that connect pairs of wires, swapping the values on the wires if they are not in a desired order. Such networks are typically designed to perform sorting on fixed numbers of values, in which case they are called sorting networks.
Sorting networks differ from general comparison sorts in that they are not capable of handling arbitrarily large inputs, and in that their sequence of comparisons is set in advance, regardless of the outcome of previous comparisons. In order to sort larger amounts of inputs, new sorting networks must be constructed. This independence of comparison sequences is useful for parallel execution and for implementation in hardware. Despite the simplicity of sorting nets, their theory is surprisingly deep and complex. Sorting networks were first studied circa 1954 by Armstrong, Nelson and O'Connor, who subsequently patented the idea.
Sorting networks can be implemented either in hardware or in software. Donald Knuth describes how the comparators for binary integers can be implemented as simple, three-state electronic devices. Batcher, in 1968, suggested using them to construct switching networks for computer hardware, replacing both buses and the faster, but more expensive, crossbar switches. Since the 2000s, sorting nets (especially bitonic mergesort) are used by the GPGPU community for constructing sorting algorithms to run on graphics processing units.
Introduction
A sorting network consists of two types of items: comparators and wires. The wires are thought of as running from left to right, carrying values (one per wire) that traverse the network all at the same time. Each comparator connects two wires. When a pair of values, traveling through a pair of wires, encounter a comparator, the comparator swaps the values if and only if the top wire's value is greater or equal to the bottom wire's value.
In a formula, if the top wire carries and the bottom wire carries , then after hitting a comparator the wires carry and , respectively, so the pair of values is sorted. A network of wires and comparators that will correctly sort all possible inputs into ascending order is called a sorting network or Kruskal hub. By reflecting the network, it is also possible to sort all inputs into descending order.
The full operation of a simple sorting network is shown below. It is evident why this sorting network will correctly sort the inputs; note that the first four comparators will "sink" the largest value to the bottom and "float" the smallest value to the top. The final comparator sorts out the middle two wires.
Depth and efficiency
The efficiency of a sorting network can be measured by its total size, meaning the number of comparators in the network, or by its depth, defined (informally) as the largest number of comparators that any input value can encounter on its way through the network. N |
https://en.wikipedia.org/wiki/NECTEC | Thailand's National Electronics and Computer Technology Center (NECTEC) is a statutory government organization under the National Science and Technology Development Agency (NSTDA), Ministry of Higher Education, Science, Research and Innovation. Its main responsibilities are to undertake, support, and promote the development of electronic, computing, telecommunication, and information technologies through research and development activities. NECTEC also disseminates and transfers such technologies for contribution to the economic growth and social development in the country, following the National Economic and Social Development Plan.
History
NECTEC was founded by the Thailand Ministry of Science, Technology and Energy on 16 September 1986. It was converted into a national centre specializing in electronics hardware and software in under National Science and Technology Development Agency. It was deemed a new agency following the enactment of the Science and Technology Development Act of 1991.
NECTEC's executive director is Dr Sarun Sumriddetchkajorn.
Mission
NECTEC contributes to the development of Thailand's capability in electronics and computer technologies through:
Research, development, design and engineering
Technology transfer to industries and communities
Human resource development
Policy research and industrial intelligence and knowledge infrastructure
Departments
Optical and Quantum Communication Lab
Intelligent Devices and Systems Research Unit
Green Testing Development Lab
Nano-Electronics and MEMS lab
Photonics Technology lab
Information Technology Management Division
Human Language Technology
Open Source Software LAb
Organization and Strategic Planning and Evaluation Division.
Human Resource and Organization Development Section
Strategic Program Management Section
Policy Research Division
Public Relations Section
R&D Services and support Section
Platform Technology Program Management Division
Rehabilitative Engineering and Assistive Technology Institute
Information Security Infrastructure and Services
Embedded Systems Technology Lab
Industrial control and Automation Lab
Software Engineering Lab
Integrated Circuits Design Section
Products
TVIS is an automatic system that reports traffic information in Bangkok.
Ya&You: It is the application for searching and providing the knowledge of medicine and health information to promote the use of drugs and healthcare properly.
Traffy bSafe for Android is a free application where users can download to make a complaint and report dangerous driving behaviour of public transportation such as vans and buses.
tangmoChecker: It is an application for checking the ripeness of watermelons
NVIS: It is an automatic system that reads out loud online news for a user.
FFC: Family Folder Collector: The purpose of this application is for healthcare personnel to collect household information when going out to the village for data collection.
Smart Sensor:A prototyping platform for Android applicat |
https://en.wikipedia.org/wiki/TMG | TMG may refer to:
Computing
TMG (language)
Microsoft Forefront Threat Management Gateway
The Master Genealogist, software
Science and technology
Tensiomyography, for detecting muscle properties
Tetramethylguanidine, a superbase
Trimethylglycine, an amino acid derivative
Trimethylgallium, Ga(CH3)3
Touring motor glider
Thermal Micrometeoroid Garment, the outer layer of a space suit
Thermomechanical generator, the Harwell Stirling engine
Music
Ted Mulry Gang, an Australian rock group
The Militia Group, a record label
Tak Matsumoto Group, a Japanese supergroup
Tiny Meat Gang, an American rap comedy duo
The Mountain Goats, an American indie rock band
Other media
Tele München Gruppe, Munich, Germany
Telegraaf Media Groep, Netherlands
Times Media Group, South Africa
Other uses
Tunney Media Group, fictional owner of NBS on Studio 60 on the Sunset Strip
Tennessee Meiji Gakuin High School
Têxtil Manuel Gonçalves, a Portuguese company
The Monitoring Group, a UK anti-racist charity
Former NYSE symbol for TransMontaigne
Trident Media Guard, a French anti-software-piracy company
Tunisia Monitoring Group, a free-expression group
Toyota Motorsport GmbH, Cologne, Germany
The Motorsports Group, a US team |
https://en.wikipedia.org/wiki/Caribbean%20Disaster%20Emergency%20Management%20Agency | The Caribbean Disaster Emergency Management Agency (CDEMA) is an inter-regional supportive network of independent emergency units throughout the Caribbean region. Formed on September 1, 2005, as the Caribbean Disaster Emergency Response Agency (CDERA), it underwent a name change to CDEMA in September 2009.
Members
The participating member states and agencies of the CDEMA include:
Activities
The stated role of the CDEMA is to coordinate disaster response to member countries. CDEMA personnel worked in Grenada and Jamaica in early September 2004 after the passage of Hurricane Ivan.
During the mid-1990s, CDEMA provided disaster support for the eruption of the Soufriere Hills volcano in Montserrat. The CDEMA also regularly monitors the Soufriere Hills volcano, in addition to the active undersea volcano named Kick 'em Jenny, to the north of Grenada. Members of the Regional Security System have also requested military and logistical assistance through the agency after natural disasters.
Background
The Pan-Caribbean Disaster Preparedness and Prevention Project (PCDPPP) was established in July 1984 to control and minimize the damage caused by severe weather in the Caribbean region and the Gulf of Mexico. Prior to the establishment of the PCDPPP, disasters in the area were addressed via private donors, a method that was heavily dependent on others and failed to help the countries of the Caribbean's cause for independence.
The PCDPPP was a collection of international sponsors such as the United States Agency for International Development (USAID), the Canadian International Development Agency, the Government of the Netherlands, and the United Nations Disaster Relief Organization (UNDRO). The PCDPPP failed to break the Caribbean's direct and indirect dependence on Europe and the United States. Ultimately, the PCDPPP failed to achieve full participation from Caribbean countries.
In 1989, after the widespread destruction of Hurricane Hugo, there was a focus on creating more effective natural disaster management and preparedness. In 1991 the Caribbean Disaster and Emergency Response Agency (CDERA) was created. CDERA was formed with 16 participating Caribbean nations. With this organization, Caribbean countries had regional support along with international support. This increased the probability of aid coming from regional sources. CDERA would later change its name to CDEMA, the Caribbean Disaster Emergency Management Agency.
History
In 1989, when the PCDPPP was beginning to fall apart, Hurricane Hugo struck the Caribbean. Relief still relied on foreign aid from countries such as the United States. By 1990 the insurance companies were criticizing the PCDPPP and how it was necessary to revise the way in which the Caribbean responded to natural disasters. The construction industry, in particular, was criticized for not enforcing enough standards to ensure that structures could withstand disasters in the Caribbean. In 1991, the PCDPPP ceased to exist, |
https://en.wikipedia.org/wiki/CHMI-DT | CHMI-DT (channel 13) is a television station licensed to Portage la Prairie, Manitoba, Canada, broadcasting the Citytv network to the Winnipeg area. Owned and operated by Rogers Sports & Media, the station has studios at 8 Forks Market Road (near Fort Gibraltar Trail and Waterfront Drive) in downtown Winnipeg, and its transmitter is located adjacent to Bohn Road (near Provincial Road 245) in Cartier.
History
In August 1980, Western Manitoba Broadcasters Ltd., owner of Brandon-based CKX-TV, met with community and business leaders to reveal their plan to start a new Portage la Prairie-based television station, with transmitter in Elie, Manitoba. The new station would employ about 20 people. There was no mention of what network it would connect to, but Craig hoped for ease of regulations that would allow him to pull in a network from the U.S. via satellite for programming. Originally some of the television programming would come from CBC Television, as like CKX, but after the CBC said they would not allow another competitive CBC broadcaster in the region because it would duplicate and cannibalize ad revenue of CBWT, Western Manitoba Broadcasters withdrew this part of the application.
An application was made in 1981 for a 287,000-watt station transmitting on VHF channel 13. Their application for a television license was denied by the Canadian Radio-television and Telecommunications Commission (CRTC) in 1981 due to "vague" programming promises.
When CKND-TV applied to the CRTC for extension of their signal into the Westman area via a transmitter in Minnedosa, CKX-TV filed an intervention opposing it, saying it would harm CKX's ad revenue. The regulatory body decided in CKX's favour. Despite this, CKND-TV-2 Minnedosa was granted a license and began broadcasting at 6 p.m. September 1, 1982.
Western Manitoba Broadcasters Ltd. applied to the CRTC again in 1985, this time promising to create a larger news department, with news bureaus in Winnipeg, Portage, Brandon and Dauphin. They intended on using call letters CPLP-TV, but later decided on CHMI-TV. The station would be seen on VHF channel 13, the last available clear channel in the region. Future licensed television stations would have to broadcast on UHF frequencies. The licensing hearing was held on December 3, 1985 in Winnipeg.
The station was licensed by the CRTC on May 8, 1986 and owned by Craig Media with a condition of licence that the station would not solicit advertising from businesses located in Winnipeg. This was to protect existing Winnipeg television stations. The station went on the air on October 17, 1986 where it was originally branded as the Manitoba Television Network or MTN. Although it has always been a Winnipeg station for all intents and purposes, for its first decade it was not allowed to sell advertising in Winnipeg.
Mark Evans was initially MTN's news director, before being replaced a year later by Al Thorgeirson.
MTN was well known for its Prairie Pulse News (later reti |
https://en.wikipedia.org/wiki/ABC%20Kids%20%28TV%20programming%20block%29 | ABC Kids (originally titled Disney's One Saturday Morning until 2002) was an American Saturday morning children's programming block that aired on ABC from September 13, 1997 to August 27, 2011. It featured a mixture of animated and live-action series from Walt Disney Television Animation and Disney Channel, aimed at children between the ages of 6 and 14. This was the only time Disney Channel content aired on over-the-air television in the United States.
The block regularly aired on Saturday mornings, though certain programs within the lineup aired on Sundays in some parts of the country due to station preferences for non-educational programming or scheduling issues with regional or network sports broadcasts.
After five years of mainly repeats of programs introduced onto the block prior to the 2007–08 season, ABC decided it would cease to provide children's programming during the Saturday morning timeslot, and entered into an agreement with Litton Entertainment to program that period; the block that resulted from this deal – Litton's Weekend Adventure, which is structured as a syndication package distributed with virtual exclusivity to ABC's owned-and-operated stations and affiliates – replaced ABC Kids on September 3, 2011.
History
Disney's One Saturday Morning
Immediately after The Walt Disney Company purchased ABC corporate parent Capital Cities/ABC Inc. in 1996, the network's children's program block ABC Saturday Morning, aired such Disney-produced series as The Mighty Ducks, Jungle Cubs and Gargoyles; it was one of two networks at the time that prominently carried Disney programming on Saturday mornings, as CBS also carried Disney cartoons (CBS' were mostly television spin-offs of Disney Renaissance films, whereas ABC's were mostly other Disney properties). After Disney formally took over ABC's operations, Disney head Michael Eisner sought to create a Saturday morning block that was different from those carried by its competitors at the time.
In February 1997, Peter Hastings left Warner Bros. Animation and joined Disney, where he was tasked with overhauling ABC's Saturday morning lineup in order to compete against Fox Kids and Kids' WB. He pitched an idea around the concept that Saturday is different from every other day of the week, and the representation of weekdays as buildings. Hastings also proposed the use of virtual set technology; although he knew a bit about it at the time and the technology used was just starting to be developed, Disney and ABC liked the idea. He hired Prudence Fenton as consultant manager and co-executive producer. Together, they sampled virtual set technology at the 1997 NAB Show and chose technology developed by Accom and ELSET. Rutherford Bench Productions, which had previously worked with Disney on other projects, hired Pacific Ocean Post (now POP Sound) to produce the virtual set. The building was initially a drawing of Grand Central Terminal with a roller coaster added but evolved into a towering mechan |
https://en.wikipedia.org/wiki/Simulink | Simulink is a MATLAB-based graphical programming environment for modeling, simulating and analyzing multidomain dynamical systems. Its primary interface is a graphical block diagramming tool and a customizable set of block libraries. It offers tight integration with the rest of the MATLAB environment and can either drive MATLAB or be scripted from it. Simulink is widely used in automatic control and digital signal processing for multidomain simulation and model-based design.
Add-on products
MathWorks and other third-party hardware and software products can be used with Simulink. For example, Stateflow extends Simulink with a design environment for developing state machines and flow charts.
MathWorks claims that, coupled with another of their products, Simulink can automatically generate C source code for real-time implementation of systems. As the efficiency and flexibility of the code improves, this is becoming more widely adopted for production systems, in addition to being a tool for embedded system design work because of its flexibility and capacity for quick iteration. Embedded Coder creates code efficient enough for use in embedded systems.
Simulink Real-Time (formerly known as xPC Target), together with x86-based real-time systems, is an environment for simulating and testing Simulink and Stateflow models in real-time on the physical system. Another MathWorks product also supports specific embedded targets. When used with other generic products, Simulink and Stateflow can automatically generate synthesizable VHDL and Verilog.
Simulink Verification and Validation enables systematic verification and validation of models through modeling style checking, requirements traceability and model coverage analysis. Simulink Design Verifier uses formal methods to identify design errors like integer overflow, division by zero and dead logic, and generates test case scenarios for model checking within the Simulink environment.
SimEvents is used to add a library of graphical building blocks for modeling queuing systems to the Simulink environment, and to add an event-based simulation engine to the time-based simulation engine in Simulink.
Release history
References
External links
Cross-platform software
Linux software
Mathematical modeling
Numerical software
Simulation programming languages
Simulation software
Visual programming languages |
https://en.wikipedia.org/wiki/MathWorks | MathWorks is an American privately held corporation that specializes in mathematical computing software. Its major products include MATLAB and Simulink, which support data analysis and simulation.
History
The company's key product, MATLAB, was created in the 1970s by Cleve Moler, who was chairman of the computer science department at the University of New Mexico at the time. It was a free tool for academics. Jack Little, who would eventually set up the company, came across the tool while he was a graduate student in electrical engineering at Stanford University.
Little and Steve Bangert rewrote the code for MATLAB in C while they were colleagues at an engineering firm. They founded MathWorks along with Moler in 1984, with Little running it out of his house in Portola Valley, California. Little would mail diskettes in baggies (food storage bags) to the first customers. The company sold its first order, 10 copies of MATLAB, for $500 to the Massachusetts Institute of Technology (MIT) in February 1985. A few years later, Little and the company moved to Massachusetts. There, Little hired Jeanne O'Keefe, an experienced computer executive, to help formalize the business. By 1997, MathWorks was profitable, claiming revenue of around $50 million, and had around 380 employees.
In 1999, MathWorks relocated to the Apple Hill office complex in Natick, Massachusetts, purchasing additional buildings in the complex in 2008 and 2009, ultimately occupying the entire campus. MathWorks expanded further in 2013 by buying Boston Scientific's old headquarters campus, which is near to MathWorks' headquarters in Natick.
By 2018, the company had around 3,000 employees in Natick and said it had revenues of around $900 million.
Products
The company's two lead products are MATLAB, which provides an environment for scientists, engineers and programmers to analyze and visualize data and develop algorithms, and Simulink, a graphical and simulation environment for model-based design of dynamic systems. MATLAB and Simulink are used in aerospace, automotive, software and other fields. The company's other products include Polyspace, SimEvents, Stateflow, and ThingSpeak.
Corporate affairs
Intellectual property and competition
In 1999, the U.S. Department of Justice filed a lawsuit against MathWorks and Wind River Systems alleging that an agreement between them violated antitrust laws. The agreement in question stipulated that the two companies agreed to stop competing in the field of dynamic control system design software, with MathWorks alone selling Wind River's MATRIXx Software and that Wind River would stop all research and development and sales in that field. Both companies eventually settled with the Department of Justice and agreed to sell the MATRIXx software to a third party. MathWorks had total sales of $200 million in 2001, with dynamic control system design software accounting for half of those sales.
MathWorks's Simulink software was found to have infringed 3 |
https://en.wikipedia.org/wiki/Cleve%20Moler | Cleve Barry Moler is an American mathematician and computer programmer specializing in numerical analysis. In the mid to late 1970s, he was one of the authors of LINPACK and EISPACK, Fortran libraries for numerical computing. He invented MATLAB, a numerical computing package, to give his students at the University of New Mexico easy access to these libraries without writing Fortran. In 1984, he co-founded MathWorks with Jack Little to commercialize this program.
Biography
He received his bachelor's degree from California Institute of Technology in 1961, and a Ph.D. in 1965 from Stanford University, both in mathematics. He worked for Charles Lawson at the Jet Propulsion Laboratory in 1961 and 1962.
He was a professor of mathematics and computer science for almost 20 years at the University of Michigan, Stanford University, and the University of New Mexico. Before joining MathWorks full-time in 1989, he also worked for Intel Hypercube, where he coined the term "embarrassingly parallel", and Ardent Computer Corporation. He is also co-author of four textbooks on numerical methods and is a member of the Association for Computing Machinery. He was president of the Society for Industrial and Applied Mathematics 2007–2008.
He was elected a member of the National Academy of Engineering on February 14, 1997, for conceiving and developing widely used mathematical software. He received an honorary degree from Linköping University, Sweden. He received an honorary degree of Doctor of Mathematics from the University of Waterloo on June 16, 2001. On April 30, 2004, he was appointed Honorary Doctor () at the Technical University of Denmark. In 2009, he was recognized by Society for Industrial and Applied Mathematics as a SIAM Fellow for his outstanding contributions to numerical analysis and software, including the invention of MATLAB. In April 2012, the IEEE Computer Society named Cleve the recipient of the 2012 Computer Pioneer Award. In February 2014, IEEE named Cleve the recipient of the 2014 IEEE John von Neumann Medal. In April 2017, he was made Fellow of the Computer History Museum.
Publications
Forsythe, George E., Malcolm, Michael A., Moler, Cleve B., "Computer methods for mathematical computations", Prentice-Hall Series in Automatic Computation, Prentice-Hall., Englewood Cliffs, N.J., 1977.
Moler, Cleve B., "Numerical Computing with MATLAB", Society for Industrial and Applied Mathematics, 2004,
References
External links
MathWorks biography of Moler
Cleve Moler, Oral history interview by Thomas Haigh, 8 and 9 March, 2004, Santa Barbara, California. Society for Industrial and Applied Mathematics, Philadelphia, PA Lengthy interview transcript covering Moler's entire career. Full text available online.
1939 births
20th-century American mathematicians
21st-century American mathematicians
Computer programmers
University of Michigan faculty
Stanford University Department of Mathematics faculty
University of New Mexico faculty
Californ |
https://en.wikipedia.org/wiki/Vertex%20cover | In graph theory, a vertex cover (sometimes node cover) of a graph is a set of vertices that includes at least one endpoint of every edge of the graph.
In computer science, the problem of finding a minimum vertex cover is a classical optimization problem. It is NP-hard, so it cannot be solved by a polynomial-time algorithm if P ≠ NP. Moreover, it is hard to approximate – it cannot be approximated up to a factor smaller than 2 if the unique games conjecture is true. On the other hand, it has several simple 2-factor approximations. It is a typical example of an NP-hard optimization problem that has an approximation algorithm. Its decision version, the vertex cover problem, was one of Karp's 21 NP-complete problems and is therefore a classical NP-complete problem in computational complexity theory. Furthermore, the vertex cover problem is fixed-parameter tractable and a central problem in parameterized complexity theory.
The minimum vertex cover problem can be formulated as a half-integral, linear program whose dual linear program is the maximum matching problem.
Vertex cover problems have been generalized to hypergraphs, see Vertex cover in hypergraphs.
Definition
Formally, a vertex cover of an undirected graph is a subset of such that , that is to say it is a set of vertices where every edge has at least one endpoint in the vertex cover . Such a set is said to cover the edges of . The upper figure shows two examples of vertex covers, with some vertex cover marked in red.
A minimum vertex cover is a vertex cover of smallest possible size. The vertex cover number is the size of a minimum vertex cover, i.e. . The lower figure shows examples of minimum vertex covers in the previous graphs.
Examples
The set of all vertices is a vertex cover.
The endpoints of any maximal matching form a vertex cover.
The complete bipartite graph has a minimum vertex cover of size .
Properties
A set of vertices is a vertex cover if and only if its complement is an independent set.
Consequently, the number of vertices of a graph is equal to its minimum vertex cover number plus the size of a maximum independent set (Gallai 1959).
Computational problem
The minimum vertex cover problem is the optimization problem of finding a smallest vertex cover in a given graph.
INSTANCE: Graph
OUTPUT: Smallest number such that has a vertex cover of size .
If the problem is stated as a decision problem, it is called the vertex cover problem:
INSTANCE: Graph and positive integer .
QUESTION: Does have a vertex cover of size at most ?
The vertex cover problem is an NP-complete problem: it was one of Karp's 21 NP-complete problems. It is often used in computational complexity theory as a starting point for NP-hardness proofs.
ILP formulation
Assume that every vertex has an associated cost of .
The (weighted) minimum vertex cover problem can be formulated as the following integer linear program (ILP).
{|
| minimize
| colspan="2" |
|
| (minimize the tota |
https://en.wikipedia.org/wiki/Matthew%20Smith%20%28games%20programmer%29 | Matthew Smith (born 1966) is a British computer game programmer. He created the games Manic Miner and Jet Set Willy for the ZX Spectrum, released in 1983 and 1984 respectively. Smith left the games industry in 1988 and later moved to the Netherlands. He has since returned to the UK and has worked on some games as well as appearing at conventions and in documentaries.
Early life
Smith was born in Penge. His family moved to Wallasey when he was seven years old.
Programming career
1980s
He started out programming when he received a TRS-80 for Christmas in 1979. His first commercial game was a Galaxian clone for the TRS-80 called Delta Tau One. He then went on to produce Monster Muncher on the VIC-20. Smith has said that he wrote Monster Muncher in 3 hours.
He obtained a ZX Spectrum on loan from Bug-Byte Software Ltd. in return for a freelance contract for three games. The first of these was Styx in 1983 for which Matthew received £3,000.
He wrote Manic Miner in eight weeks using a Model III Tandy. It was the first ZX Spectrum title with in-game music. The sequel, Jet Set Willy, took considerably longer to write. Manic Miner and Jet Set Willy were both commercial successes. Smith has stated that Manic Miner was the most enjoyable game to make for him whereas Jet Set Willy was 'seven shades of hell'.
After the creation of Jet Set Willy he started work on The Mega Tree (commonly known as Willy Meets The Taxman), for publication by his company Software Projects. Unlike his previous two hits The Mega Tree was not developed for the ZX Spectrum but the Commodore 64. The project failed to gain traction and was cancelled three months into development. The development disks containing some of the graphics from the unreleased game were eventually auctioned for charity in 2004.
In 1987 adverts began appearing in games magazines for a new game Attack of the Mutant Zombie Flesh Eating Chickens From Mars said to have been programmed by Smith, and due for release by Software Projects. It is reported that Smith was unhappy with the finished product and it was never released.
Departure
Smith closed Software Projects in 1988 without completing any more programs. He lived in a Dutch commune from around 1995 but was deported from the Netherlands in October 1997 and returned to Britain, saying that he had failed to keep his residency papers in order. In the late 1990s, he said he was "surprised and flattered" at the amount of attention and speculation he had attracted on the Internet.
Return to games
In 1999 Smith returned to the UK video game industry by taking a job at Dewsbury-based computer game developer Runecraft.
In 2000, he appeared on a British television documentary programme called Thumb Candy about the history of video games in which, in a brief interview, he discussed Manic Miner and his 1980's career. He has also attended and given talks at retrogaming conventions during this decade.
In 2013, Smith was working on producing a new game with El |
https://en.wikipedia.org/wiki/POP-11 | POP-11 is a reflective, incrementally compiled programming language with many of the features of an interpreted language. It is the core language of the Poplog programming environment developed originally by the University of Sussex, and recently in the School of Computer Science at the University of Birmingham, which hosts the main Poplog website.
POP-11 is an evolution of the language POP-2, developed in Edinburgh University, and features an open stack model (like Forth, among others). It is mainly procedural, but supports declarative language constructs, including a pattern matcher, and is mostly used for research and teaching in artificial intelligence, although it has features sufficient for many other classes of problems. It is often used to introduce symbolic programming techniques to programmers of more conventional languages like Pascal, who find POP syntax more familiar than that of Lisp. One of POP-11's features is that it supports first-class functions.
POP-11 is the core language of the Poplog system. The availability of the compiler and compiler subroutines at run-time (a requirement for incremental compilation) gives it the ability to support a far wider range of extensions (including run-time extensions, such as adding new data-types) than would be possible using only a macro facility. This made it possible for (optional) incremental compilers to be added for Prolog, Common Lisp and Standard ML, which could be added as required to support either mixed language development or development in the second language without using any POP-11 constructs. This made it possible for Poplog to be used by teachers, researchers, and developers who were interested in only one of the languages. The most successful product developed in POP-11 was the Clementine Data-mining system, developed by ISL. After SPSS bought ISL they decided to port Clementine to C++ and Java, and eventually succeeded with great effort (and perhaps some loss of the flexibility provided by the use of an AI language).
POP-11 was for a time available only as part of an expensive commercial package (Poplog), but since about 1999 it has been freely available as part of the Open Source version of Poplog, including various additional packages and teaching libraries. An online version of ELIZA using POP-11 is available at Birmingham.
At the University of Sussex, David Young used POP-11 in combination with C and Fortran to develop a suite of teaching and interactive development tools for image processing and vision, and has made them available in the Popvision extension to Poplog.
Simple code examples
Here is an example of a simple POP-11 program:
define Double(Source) -> Result;
Source*2 -> Result;
enddefine;
Double(123) =>
That prints out:
** 246
This one includes some list processing:
<nowiki>
define RemoveElementsMatching(Element, Source) -> Result;
lvars Index;
[[%
for Index in Source do
unless Index = Element or Index matches Element |
https://en.wikipedia.org/wiki/Hugs%20%28interpreter%29 | Hugs (Haskell User's Gofer System), also Hugs 98, is a bytecode interpreter for the functional programming language Haskell. Hugs is the successor to Gofer, and was originally derived from Gofer version 2.30b. Hugs and Gofer were originally developed by Mark P. Jones, now a professor at Portland State University.
Hugs comes with a simple graphics library. As a complete Haskell implementation that is portable and simple to install, Hugs is sometimes recommended for new Haskell users.
Hugs deviates from the Haskell 98 specification in several minor ways. For example, Hugs does not support mutually recursive modules. A list of differences exists.
The Hugs prompt is a Haskell read–eval–print loop (REPL). It accepts expressions for evaluation, but not module, type, or function definitions. Hugs can load Haskell modules at start-up.
Examples
Extensible records
An example of "Typed records with extensibility", a non standard feature unique to Hugs.
module Main where
import Hugs.Trex
type Coord = Double
type Point2D = Rec (x::Coord, y::Coord)
type Point3D = Rec (x::Coord, y::Coord, z::Coord)
point2D = (x=1, y=1) :: Point2D
-- emptyRec :: Rec EmptyRow -- predefined
-- (x=1 | (y=1)) -- rec. extension
-- (x=v | rec) -- record value decomposition, pattern fields must be non empty
-- (x::type | rec) -- record type decomposition
-- (rec\z) in the context means ''rec'' does not contain field ''z''
-- add a field z with the same type as field x
addZCoord :: (r\z, r\x) => t -> Rec ( x::t | r) -> Rec ( x::t, z::t | r)
addZCoord z ( x = x | other) = (x = x, z = z | other)
point3D = addZCoord 3 point2D -- :: Point3D
-- admit any record with ''showable'' fields x and y
printXY :: (Show t, r\x, r\y) => Rec (x::t, y::t | r) -> IO ()
printXY point = putStrLn xy
-- with SML style field accessors ('#' prefix)
where xy = show (#x point) ++", "++ show (#y point)
incrementX :: (Num t, r\x) => Rec (x::t | r) -> Rec (x::t | r)
incrementX (x=v | rest) = (x=v+1 | rest)
main = do
let point3D' = incrementX point3D
printXY point2D
printXY point3D'
Running with H98 compatibility turned off to activate language extensions:
runhugs -98 test.hs
References
External links
Free Haskell implementations
Software using the BSD license |
https://en.wikipedia.org/wiki/Vista | Vista usually refers to a distant view.
Vista may also refer to:
Software
Windows Vista, the line of Microsoft Windows client operating systems released in 2006 and 2007
VistA, (Veterans Health Information Systems and Technology Architecture) a medical records system of the United States Department of Veterans Affairs and others worldwide
VISTA (comparative genomics), software tools for genome analysis and genomic sequence comparisons
VistaPro, and Vista, 3D landscape generation software for the Amiga and PC
VIsualizing STructures And Sequences, bioinformatics software
Organizations and institutions
Vista Group, a New Zealand software company specializing in solutions for the cinema industry
AmeriCorps VISTA, a national service program to fight poverty through local government agencies and non-profit organizations
Ventura Intercity Service Transit Authority, a public transportation agency in Ventura County, California, US
Vista Community College, now Berkeley City College, a community college in Berkeley, California, US
Vista Federal Credit Union, now merged with Partners Federal Credit Union, a credit union that serves employees of The Walt Disney Company
Vista University, a now-closed South African university
Volunteers in Service to America
Vista Equity Partners
Vista Oil & Gas, an oil and gas company founded by Miguel Galuccio
Vista Outdoor, an American-based publicly-traded outdoor and shooting sports company
Vista Global, an UAE-based private aviation group
VistaJet, a Malta-based business aviation company
Places
Vista, California, United States
Playa Vista, Los Angeles, United States
Vista, Manitoba, Canada
Vista, Minnesota, United States
Vista, Missouri, United States
Vista, New York, United States
Vista, South Australia, Australia
Boa Vista, Roraima, Brazil
Boa Vista, Cape Verde
Buona Vista, Singapore
Chula Vista, California, United States
Isla Vista, California, United States
La Vista, Nebraska, United States
Mount Vista, Washington, United States
Sierra Vista, Arizona, United States
Vista Center, New Jersey, United States
Vista Hundred, Sweden
Vista Tower (Chicago), United States
Vista West, Wyoming, United States
Vista (Hong Kong)
Vehicles
Aeroprakt A-20 Vista, ultralight aircraft
Eagle Vista, a rebadged Mitsubishi Mirage sold under the Eagle brand from 1988–1992
Mitsubishi Chariot, also known as Dodge / Plymouth Colt Vista Wagon, a compact MPV
NF-16D VISTA, a variant of the Lockheed Martin F-16 fighter aircraft range with thrust vector control
Oldsmobile Vista Cruiser, a station wagon produced by Oldsmobile until 1977
Thomas Vista, a school bus produced by Thomas Built Buses until 1998
Toyota Vista, a passenger car produced by Toyota until 2003
Indica Vista, a passenger car produced by Tata Motors
Vista-class cruise ship (2002), a class of Panamax-type cruise ships
Vista-class cruise ship (2016), a class of cruise ships operated by the Carnival Cruise Lines
Other
VISTA (protein), an immune checkpoint protein that inhibits imm |
https://en.wikipedia.org/wiki/Glasgow%20Haskell%20Compiler | The Glasgow Haskell Compiler (GHC) is a native or machine code compiler for the functional programming language Haskell. It provides a cross-platform software environment for writing and testing Haskell code and supports many extensions, libraries, and optimisations that streamline the process of generating and executing code. GHC is the most commonly used Haskell compiler. It is free and open-source software released under a BSD license. The lead developers are Simon Peyton Jones and Simon Marlow.
History
GHC originally begun in 1989 as a prototype, written in Lazy ML (LML) by Kevin Hammond at the University of Glasgow. Later that year, the prototype was completely rewritten in Haskell, except for its parser, by Cordelia Hall, Will Partain, and Simon Peyton Jones. Its first beta release was on 1 April 1991. Later releases added a strictness analyzer and language extensions such as monadic I/O, mutable arrays, unboxed data types, concurrent and parallel programming models (such as software transactional memory and data parallelism) and a profiler.
Peyton Jones, and Marlow, later moved to Microsoft Research in Cambridge, where they continued to be primarily responsible for developing GHC. GHC also contains code from more than three hundred other contributors.
Since 2009, third-party contributions to GHC have been funded by the Industrial Haskell Group.
GHC names
Since early releases the official website has referred to GHC as The Glasgow Haskell Compiler, whereas in the executable version command it is identified as The Glorious Glasgow Haskell Compilation System. This has been reflected in the documentation. Initially, it had the internal name of The Glamorous Glasgow Haskell Compiler.
Architecture
GHC is written in Haskell, but the runtime system for Haskell, essential to run programs, is written in C and C--.
GHC's front end, incorporating the lexer, parser and typechecker, is designed to preserve as much information about the source language as possible until after type inference is complete, toward the goal of providing clear error messages to users. After type checking, the Haskell code is desugared into a typed intermediate language known as "Core" (based on System F, extended with let and case expressions). Core has been extended to support generalized algebraic datatypes in its type system, and is now based on an extension to System F known as System FC.
In the tradition of type-directed compiling, GHC's simplifier, or "middle end", where most of the optimizations implemented in GHC are performed, is structured as a series of source-to-source transformations on Core code. The analyses and transformations performed in this compiler stage include demand analysis (a generalization of strictness analysis), application of user-defined rewrite rules (including a set of rules included in GHC's standard libraries that performs foldr/build fusion), unfolding (called "inlining" in more traditional compilers), let-floating, an analysis that de |
https://en.wikipedia.org/wiki/Dc%20%28computer%20program%29 | dc (desk calculator) is a cross-platform reverse-Polish calculator which supports arbitrary-precision arithmetic. Written by Lorinda Cherry and Robert Morris at Bell Labs, it is one of the oldest Unix utilities, preceding even the invention of the C programming language. Like other utilities of that vintage, it has a powerful set of features but terse syntax.
Traditionally, the bc calculator program (with infix notation) was implemented on top of dc.
This article provides some examples in an attempt to give a general flavour of the language; for a complete list of commands and syntax, one should consult the man page for one's specific implementation.
History
dc is the oldest surviving Unix language program. When its home Bell Labs received a PDP-11, dcwritten in Bwas the first language to run on the new computer, even before an assembler. Ken Thompson has opined that dc was the very first program written on the machine.
Basic operations
To multiply four and five in dc (note that most of the whitespace is optional):
$ cat << EOF > cal.txt
4 5 *
p
EOF
$ dc cal.txt
20
$
The results are also available from the commands:
$ echo "4 5 * p" | dc
or
$ dc -
4 5*pq
20
$ dc
4 5 *
p
20
q
$ dc -e '4 5 * p'
This translates into "push four and five onto the stack, then, with the multiplication operator, pop two elements from the stack, multiply them and push the result onto the stack." Then the p command is used to examine (print out to the screen) the top element on the stack. The q command quits the invoked instance of dc. Note that numbers must be spaced from each other even as some operators need not be.
The arithmetic precision is changed with the command k, which sets the number of fractional digits (the number of digits following the point) to be used for arithmetic operations. Since the default precision is zero, this sequence of commands produces 0 as a result:
2 3 / p
By adjusting the precision with k, an arbitrary number of decimal places can be produced. This command sequence outputs .66666.
5 k
2 3 / p
To evaluate : (v computes the square root of the top of the stack and _ is used to input a negative number):
12 _3 4 ^ + 11 / v 22 -
p
To swap the top two elements of the stack, use the r command. To duplicate the top element, use the d command.
Input/output
To read a line from stdin, use the ? command. This evaluates the line as if it were a dc command, and so it is necessary that it be syntactically correct and presents a potential security problem because the ! dc command enables arbitrary command execution.
As mentioned above, p prints the top of the stack with a newline after it. n pops the top of the stack and prints it without a trailing newline. f prints the entire stack with one entry per line.
dc also supports arbitrary input and output radices. The i command pops the top of the stack and uses it for the input base. Hex digits must be in upper case to avoid collisions with dc commands and are limited to A-F. The o comma |
https://en.wikipedia.org/wiki/Cartoon%20Network%20%28Canadian%20TV%20channel%29 | Cartoon Network (formerly Teletoon) is a Canadian English-language discretionary specialty channel owned by Corus Entertainment. The channel primarily broadcasts animated series aimed at children and teenagers.
It was launched on October 17, 1997, by Teletoon Canada, Inc., a consortium of Western International Communications and Astral Media (via their specialty channel Family Channel), Shaw Communications (via its specialty channel YTV), and the animation studios Cinar and Nelvana. With subsequent acquisitions and divestments, Corus became the sole owner of the channel in 2014.
The channel has historically aired a mix of domestic productions and imported series, with many of the latter coming from U.S. channel Cartoon Network. In 2012, Teletoon launched a Canadian version of Cartoon Network as a sister network under license from Turner Broadcasting. In February 2023, Corus announced that Teletoon itself would rebrand as Cartoon Network on March 27, 2023, with the previous Cartoon Network channel concurrently relaunching under Cartoon Network's own sister brand Boomerang.
Cartoon Network operates two timeshift feeds running on Eastern and Pacific schedules. Along with its French-language counterpart Télétoon, it is available in over 7.3 million households in Canada as of November 2013.
History
As Teletoon
In 1997, Teletoon was licensed by the Canadian Radio-television and Telecommunications Commission (CRTC) after a related application for a channel to be called "Fun TV" had been denied. The channel launched on October 17, 1997. The channel was originally owned by a consortium of other Canadian specialty services, including Family Channel acting as managing partner at 53.3% (Superchannel/WIC and The Movie Network/Astral Media), YTV at 26.7%, (Shaw Communications), along with the Canadian animation studios Cinar and Nelvana with 10% each. Shaw spun off its entertainment assets as Corus Entertainment in 1999, which subsequently acquired WIC's stake in Family Channel among other assets as part of its breakup later that year, Corus acquired Nelvana in 2000.
Teletoon was licensed as a bilingual service in both English and French, being one of only two Canadian speciality services with such a license; the channel maintains two feeds under the license, with the French feed operating under the branding Télétoon. At the original licensing hearing before the CRTC, the network's operators had stated that the two channels "would be similar in nature and programmed with a similar attitude towards them", but that there may be differences in their programming due to market differences (including Quebec's prohibition on advertising to children) and program rights. To this end, Teletoon often commissioned programming to air in both English and French whenever possible.
As a condition of the license, Teletoon committed to devoting 40% of its programming to Canadian content in its first year of operation, gradually increasing by five per cent yearly to 60% |
https://en.wikipedia.org/wiki/List%20of%20software%20patents | This is a list of software patents, which contains notable patents and patent applications involving computer programs (also known as a software patent). Software patents cover a wide range of topics and there is therefore important debate about whether such subject-matter should be excluded from patent protection. However, there is no official way of identifying software patents and different researchers have devised their own ways of doing so.
This article lists patents relating to software which have been the subject of litigation or have achieved notoriety in other ways. Notable patent applications are also listed and comparisons made between corresponding patents and patent applications in different countries. The patents and patent applications are categorised according to the subject matter of the patent or the particular field in which the patent had an effect that brought it into the public view.
Business methods
Data compression
Data compression in general
(Main article: Stac Electronics)
also granted as - now expired
Stac Electronics sued Microsoft for patent infringement when Microsoft introduced the DoubleSpace data compression scheme into MS-DOS. Stac was awarded $120 million by a jury in 1994 and Microsoft was ordered to recall versions of MS-DOS with the infringing technology.
Audio compression
(Main article: MP3)
One of several patents covering the MP3 format owned by the Fraunhofer Society which led to the development of the Ogg Vorbis format as an alternative to MP3.
(Main article: Alcatel-Lucent v. Microsoft)
Two patents owned by Alcatel-Lucent relating to MP3 technology under which they sued Microsoft for $1.5 billion. Microsoft thought they had already licensed the technology from Fraunhofer, and this case illustrates one of the basic principles of patents that a license does not necessarily permit the licensee to work the technology, but merely prevents the licensee from being sued by the licensor.
Image compression
(Main article: GIF)
Unisys's patent on LZW compression, a fundamental part of the widely used GIF graphics format.
and its EP equivalent
(Main article: Forgent Networks)
Forgent Networks claimed this patent, granted in 1987, covered the JPEG image compression format. The broadest claims of the US patent were found to be invalid in 2005 following re-examination by the US Patent and Trademark Office.
This patent, owned by Lizardtech, Inc., was the subject of infringement proceedings against companies including Earth Resource Mapping, Inc. However, Lizardtech lost the trial on the grounds that an important part of their invention was the step of "maintaining updated sums of discrete wavelet transform coefficients from the discrete tile image to form a seamless discrete wavelet transform of the image". Claim 21 of the patent lacked this feature and was therefore obvious. The remaining claims contained this feature, but were not infringed by ERM. Internet buzz suggested the paten |
https://en.wikipedia.org/wiki/Sat.1 | Sat.1 () is a German free-to-air television channel that is a part of the ProSiebenSat.1 Media Group.
It is considered the first privately owned television network in Germany, having been launched in January 1984 as PKS (Programmgesellschaft für Kabel- und Satellitenrundfunk), initially a joint venture of various publishing houses, and was rebranded as Sat.1 in January 1985. The first broadcast could only be seen by roughly 1200 households who had cable access in the city of Ludwigshafen. Early programs included old films (mainly from the archives of KirchMedia) American hit series and game shows (the most notable show being the German version of Wheel of Fortune, Glücksrad). Later, the station acquired a name for its original series and TV films. By 1988, it was the most watched tv channel in West Germany.
Pay-TV sister channel Sat.1 Emotions (formerly Sat.1 Comedy) airs comedy, romance and movies. In 2013 Sat.1 Gold, a second, free-to-air Sat.1 offshoot was also launched.
In addition to its free-to-air standard definition feed, Sat.1 also broadcasts an HD feed as a subscription-only channel, available on Astra's HD+ satellite pay-TV platform.
Sat.1 Regional
Regional newscasts are broadcast under the title 17:30 Sat.1... in Bremen, Lower Saxony, Hamburg, Schleswig-Holstein, North Rhine-Westphalia, Rhineland-Palatinate, Hesse and Bavaria.
17:30 Sat.1 live (Rhineland-Palatinate and Hesse)
17:30 Sat.1 NRW (North Rhine-Westphalia)
17:30 Sat.1 Regional (Hamburg and Schleswig-Holstein)
17:30 Sat.1 Regional (Lower Saxony and Bremen)
17:30 Sat.1 Bayern (Bavaria).
Programmes
Children
The Bugs Bunny Show (2000 - 2008?)
Entertainment
5 mal 5, German version of Lingo hosted by Bernd Schumacher (1993-1994)
Aus den Augen verloren, hosted by Jörg Wontorra (1995-1996)
Bingo, hosted by Wolf-Dieter Herrmann (1991-1992)
Bitte melde dich!, hosted by Jörg Wontorra (1992-1998)
Die Comedy-Falle, hosted by Kai Pflaume (2005-2011)
Die Harald Schmidt Show, late-night show hosted by Harald Schmidt (1995–2004, 2011–2012)
Die Hella von Sinnen Show, hosted by Hella von Sinnen (2006)
Die Hit-Giganten, hosted by Hugo Egon Balder (2003-2012)
Die MyVideo-Show, hosted by Annika Lau (2006-2007)
Erben gesucht, hosted by Jörg Wontorra (1994)
Geh aufs Ganze!, hosted by Jörg Draeger (1992-1997)
Genial daneben, hosted by Hugo Egon Balder (2003-2011, 2017–2021)
Glücksrad, German version of Wheel of Fortune (1988-1997)
Got to Dance, hosted by Alexandra Maurer (2013-2014)
Got to Dance Kids, hosted by Alexandra Maurer (2015)
Jeder gegen Jeden, German version of Fifteen to One hosted by Hans-Hermann Gockel (1996-2001)
Jetzt reicht's!, hosted by Vera Int-Veen (1997-1998)
Kampf der Köche - Wer haut den Profi in die Pfanne? (2016)
Kämpf um deine Frau!, hosted by Andrea Kiewel (2004)
Krypton Faktor, German version of The Krypton Factor hosted by Jörg Draeger (1991)
Man O Man, hosted by Peer Augustinski (1992-1995)
Newtopia - Vollkommenes Glück oder totales Chaos?, German ver |
https://en.wikipedia.org/wiki/Approximation%20algorithm | In computer science and operations research, approximation algorithms are efficient algorithms that find approximate solutions to optimization problems (in particular NP-hard problems) with provable guarantees on the distance of the returned solution to the optimal one. Approximation algorithms naturally arise in the field of theoretical computer science as a consequence of the widely believed P ≠ NP conjecture. Under this conjecture, a wide class of optimization problems cannot be solved exactly in polynomial time. The field of approximation algorithms, therefore, tries to understand how closely it is possible to approximate optimal solutions to such problems in polynomial time. In an overwhelming majority of the cases, the guarantee of such algorithms is a multiplicative one expressed as an approximation ratio or approximation factor i.e., the optimal solution is always guaranteed to be within a (predetermined) multiplicative factor of the returned solution. However, there are also many approximation algorithms that provide an additive guarantee on the quality of the returned solution. A notable example of an approximation algorithm that provides both is the classic approximation algorithm of Lenstra, Shmoys and Tardos for scheduling on unrelated parallel machines.
The design and analysis of approximation algorithms crucially involves a mathematical proof certifying the quality of the returned solutions in the worst case. This distinguishes them from heuristics such as annealing or genetic algorithms, which find reasonably good solutions on some inputs, but provide no clear indication at the outset on when they may succeed or fail.
There is widespread interest in theoretical computer science to better understand the limits to which we can approximate certain famous optimization problems. For example, one of the long-standing open questions in computer science is to determine whether there is an algorithm that outperforms the 2-approximation for the Steiner Forest problem by Agrawal et al. The desire to understand hard optimization problems from the perspective of approximability is motivated by the discovery of surprising mathematical connections and broadly applicable techniques to design algorithms for hard optimization problems. One well-known example of the former is the Goemans–Williamson algorithm for maximum cut, which solves a graph theoretic problem using high dimensional geometry.
Introduction
A simple example of an approximation algorithm is one for the minimum vertex cover problem, where the goal is to choose the smallest set of vertices such that every edge in the input graph contains at least one chosen vertex. One way to find a vertex cover is to repeat the following process: find an uncovered edge, add both its endpoints to the cover, and remove all edges incident to either vertex from the graph. As any vertex cover of the input graph must use a distinct vertex to cover each edge that was considered in the process (since it |
https://en.wikipedia.org/wiki/Excitatory%20synapse | An excitatory synapse is a synapse in which an action potential in a presynaptic neuron increases the probability of an action potential occurring in a postsynaptic cell. Neurons form networks through which nerve impulses travels, each neuron often making numerous connections with other cells of neurons. These electrical signals may be excitatory or inhibitory, and, if the total of excitatory influences exceeds that of the inhibitory influences, the neuron will generate a new action potential at its axon hillock, thus transmitting the information to yet another cell.
This phenomenon is known as an excitatory postsynaptic potential (EPSP). It may occur via direct contact between cells (i.e., via gap junctions), as in an electrical synapse, but most commonly occurs via the vesicular release of neurotransmitters from the presynaptic axon terminal into the synaptic cleft, as in a chemical synapse.
The excitatory neurotransmitters, the most common of which is glutamate, then migrate via diffusion to the dendritic spine of the postsynaptic neuron and bind a specific transmembrane receptor protein that triggers the depolarization of that cell. Depolarization, a deviation from a neuron's resting membrane potential towards its threshold potential, increases the likelihood of an action potential and normally occurs with the influx of positively charged sodium (Na+) ions into the postsynaptic cell through ion channels activated by neurotransmitter binding.
Chemical vs electrical synapses
There are two different kinds of synapses present within the human brain: chemical and electrical. Chemical synapses are by far the most prevalent and are the main player involved in excitatory synapses. Electrical synapses, the minority, allow direct, passive flow of electric current through special intercellular connections called gap junctions. These gap junctions allow for virtually instantaneous transmission of electrical signals through direct passive flow of ions between neurons (transmission can be bidirectional). The main goal of electrical synapses is to synchronize electrical activity among populations of neurons. The first electrical synapse was discovered in a crayfish nervous system.
Chemical synaptic transmission is the transfer of neurotransmitters or neuropeptides from a presynaptic axon to a postsynaptic dendrite. Unlike an electrical synapse, the chemical synapses are separated by a space called the synaptic cleft, typically measured between 15 and 25 nm. Transmission of an excitatory signal involves several steps outlined below.
Synaptic transmission
In neurons that are involved in chemical synaptic transmission, neurotransmitters are synthesized either in the neuronal cell body, or within the presynaptic terminal, depending on the type of neurotransmitter being synthesized and the location of enzymes involved in its synthesis. These neurotransmitters are stored in synaptic vesicles that remain bound near the membrane by calcium-influenced pro |
https://en.wikipedia.org/wiki/EyeTap | An EyeTap is a concept for a wearable computing device that is worn in front of the eye that acts as a camera to record the scene available to the eye as well as a display to superimpose computer-generated imagery on the original scene available to the eye. This structure allows the user's eye to operate as both a monitor and a camera as the EyeTap intakes the world around it and augments the image the user sees allowing it to overlay computer-generated data over top of the normal world the user would perceive.
In order to capture what the eye is seeing as accurately as possible, an EyeTap uses a beam splitter to send the same scene (with reduced intensity) to both the eye and a camera. The camera then digitizes the reflected image of the scene and sends it to a computer. The computer processes the image and then sends it to a projector. The projector sends the image to the other side of the beam splitter so that this computer-generated image is reflected into the eye to be superimposed on the original scene. Stereo EyeTaps modify light passing through both eyes, but many research prototypes (mainly for reasons of ease of construction) only tap one eye.
EyeTap is also the name of an organization founded by inventor Steve Mann to develop and promote EyeTap-related technologies such as wearable computers.
Possible uses
An EyeTap is somewhat like a head-up display (HUD). The important difference is that the scene available to the eye is also available to the computer that projects the head-up display. This enables the EyeTap to modify the computer generated scene in response to the natural scene. One use, for instance, would be a sports EyeTap: here the wearer, while in a stadium, would be able to follow a particular player in a field and have the EyeTap display statistics relevant to that player as a floating box above the player. Another practical use for the EyeTap would be in a construction yard as it would allow the user to reference the blueprints, especially in a 3D manner, to the current state of the building, display a list of current materials and their current locations as well perform basic measurements. Or, even in the business world, the EyeTap has great potential, for it would be capable of delivering to the user constant up to date information on the stock market, the user's corporation, and meeting statuses. On a more day-to-day basis some of Steve Mann's first uses for the technology was using it to keep track of names of people and places, his to-do lists, and keeping track of his other daily ordeals. The EyeTap Criteria are an attempt to define how close a real, practical device comes to such an ideal. EyeTaps could have great use in any field where the user would benefit from real-time interactive information that is largely visual in nature. This is sometimes referred to as computer-mediated reality, commonly known as augmented reality.
Eyetap has been explored as a potential tool for individuals with visual disabilities |
https://en.wikipedia.org/wiki/DISCiPLE | The DISCiPLE is a floppy disk interface for the ZX Spectrum home computer. Designed by Miles Gordon Technology, it was marketed by Rockfort Products and launched in 1986.
Like Sinclair's own ZX Interface 1, the DISCiPLE was a wedge-shaped unit fitting underneath the Spectrum. It was designed as a super-interface, providing all the facilities a Spectrum owner could need. In addition to floppy-disk, parallel port printer interface and a "magic button" (see Non-maskable interrupt), it also offered twin joystick ports, Sinclair ZX Net-compatible network ports and an inhibit button for disabling the device.
At the rear of the unit was a pass-through port for connecting further devices, although the complexity of the DISCiPLE meant that many would not work, or only if the DISCiPLE was "turned off" using the inhibit button.
The DISCiPLE was a considerable success but its sophistication (the device included 8kB of ROM) meant that it was expensive and the plastic casing, located beneath the computer itself, was sometimes prone to overheating. These factors led to the development of MGT's later +D interface.
The DISCiPLE's DOS was named GDOS. MGT's later DOSs (G+DOS for the +D, and SAM DOS for the SAM Coupé) were backwards-compatible with GDOS. In later years a complete new system called UNI-DOS was developed by SD Software for the DISCiPLE and +D interfaces. In October 1993 "The Complete DISCiPLE Disassembly" was published in book form, documenting the "GDOS system 3d" version.
The popularity of the DISCiPLE led to the formation of a user group and magazine, INDUG, which later became Format Publications. Usergroups like INDUG/Format in the UK or DISCiPLE-Nieuwsbrief in the Netherlands produced enhancements such as extended printer support.
See also
Beta Disk Interface
References
Microcomputers
Home computers
ZX Spectrum
Computer storage devices |
https://en.wikipedia.org/wiki/%2BD | The +D (or Plus D) was a floppy disk and printer interface for the ZX Spectrum home computer, developed as a successor to Miles Gordon Technology's earlier product, the DISCiPLE. It was designed to be smaller, cheaper, simpler and thus more reliable.
It discarded a number of the less important features of the earlier product — the network and joystick ports, the inhibit button and the pass-through connector — and replaced its ancestor's plastic wedge-shaped design which fit under the Spectrum with a simple flat metal slab which protruded from the rear of the computer.
It provided only floppy disk and Centronics parallel interfaces, plus a non-maskable interrupt button. The +D's casing was simple folded steel, which was not only stronger than before but acted as a heatsink, improving reliability. Apart from the missing ports, though, it was software-compatible with the larger device.
The +D's DOS was named G+DOS, and was compatible with the DISCiPLE's DOS, GDOS. SAM DOS for MGT's SAM Coupé was backwards-compatible with GDOS and G+DOS. "The Complete +D Disassembly" by Rudy Biesma documents the "G+DOS system 2a" version. An enhanced version called Beta DOS fixed bugs and added features.
In later years a complete new system called UNI-DOS was developed by SD Software for the DISCiPLE and +D interfaces.
The popularity of the DISCiPLE led to the formation of a user group and magazine, INDUG, which later became Format Publications. Usergroups like INDUG/Format in the UK or DISCiPLE-Nieuwsbrief in the Netherlands produced enhancements such as extended printer support.
The +D design was later licensed by Datel and it continued on sale for some years after MGT's demise. Its design and chips have been released into the public domain and it still remains available commercially or even as a DIY project.
References
External links
How to build a +D for yourself
rwapsoftware.co.uk still offer the +D Disk Interface for sale
ZX Spectrum |
https://en.wikipedia.org/wiki/VTech%20Laser%20200 | The VTech Laser 200 is an 8-bit home computer from 1983, also sold as the Salora Fellow (mainly in Fennoscandia, particularly Finland), the Seltron 200 in Hungary and Italy, the Smart-Alec Jr. by Dynasty Computer Corporation in Dallas, Texas for the USA, the Texet TX8000A (in the United Kingdom), and the Dick Smith VZ 200 (in Australia and New Zealand) and the VTech VZ 200 (in the United States and Canada).
Video Technology manufactured calculators and LCD pad game toys (similar to Nintendo Game & Watch) at a rather claustrophobic multi-storey factory in Hong Kong. The VZ200 is a development of an earlier monochrome TRS-80 copy, and is similar to the EACA Colour Genie and the Mattel Aquarius.
The machine ran basic games on cassette such as Hoppy (a version of Frogger), Cosmic Rescue (Scramble), VZ Invaders (Space Invaders), Dawn Patrol (Chopper) and Moon Patrol. The Laser 200/210 and VZ200 computers were discontinued in 1985 being replaced by the Laser 310 and VZ300 computers.
Release
Released in 1983, the VZ200 gained some following in northern America and Europe. However, in the US the Timex TS1000 undercut the VZ200 selling for $30. It gained a measurable following in countries, where it was supported by the distributor, where Sinclair Research was too disorganised to have any impact.
Due to Dick Smith Electronics extensive advertising throughout Australia and New Zealand, the computer gained large popularity. The "Dick Smith"-badged VZ 200 was successful in Australia, where it proved popular as a first computer. By 1984, a Dick Smith Electronics catalogue announced that over 30,000 units had sold within the first 12 months. In Australia, it was bought mostly to learn programming; the only other widely available system in the same price bracket being the Commodore 64. The VZ200 version of BASIC had more features compared to the Commodore 64 BASIC.
The VZ200 had little impact in the UK where it sold at a similar price to the 16 kB Sinclair Spectrum. At its UK launch, Texet claimed that the £98 () TX8000-branded version was the cheapest colour home microcomputer on the market. However, this was not enough to ensure its success against the dominant ZX Spectrum and similar machines already on sale.
An improved version known as the VTech Laser 310, or the Dick Smith VZ 300 featured a full travel keyboard and 8K ROM software based Floppy Disk Controller, was released in 1985 and continued until 1989.
Laser310's were a huge success throughout China. Many Primary schools had the Laser310 sitting along ide Apple ][e's during the late 1980's
Technical specification Laser200/Laser210/VZ200
The VZ200 has three circuit boards, the video board and voltage regulator being separate to the main board.
Externally, the VZ200 resembles a cross between the VIC-20 and the ZX Spectrum. The VZ200 has the one touch command keys of the Spectrum, but unlike the Sinclair machines, their use was not mandatory.
Internally, the VZ200 is a workalike of the Tand |
https://en.wikipedia.org/wiki/ZX%20Interface%201 | A peripheral from Sinclair Research for its ZX Spectrum home computer, the ZX Interface 1 was launched in 1983. Originally intended as a local area network interface for use in school classrooms, it was revised before launch to also act as the controller for up to eight ZX Microdrive high-speed tape-loop cartridge drives. It also included a DE-9 RS-232 interface capable of operating at up to 19.2 kbit/s. At hardware level it was fundamentally a voltage adaptor, the serial protocol being implemented in software by bit-banging. This led to problems when receiving data, but not when transmitting.
A wedge-shaped device fitting underneath the ZX Spectrum, for correct fitment 2 screws needed to be removed from the underside of the Spectrum, the existing screwholes being used by longer screws running through the ZX Interface 1 to stop it from coming inadvertently attatched, the ZX Interface 1 contained of ROM comprising the control software for the Microdrives, an RS-232 port and network interface. This extended the error handler in the Sinclair BASIC to allow extra keywords to be used. As this became an official standard, other developers quickly used this mechanism to create language extensions to Sinclair BASIC.
Two further revisions of the device's firmware were made following launch. These aimed to improve ZX Microdrive cartridge formatting and access time, printing functions via the RS-232 interface, and other bugs in the firmware held in the device's internal 8K ROM. Machine code software which used the officially documented entry points ('hook codes') would experience few incompatibility issues; however, programs using non-standard entry points risked incompatibility due to the presence of revised entry points.
The same protocol, renamed QLAN, was later used on the Sinclair QL. This was intended to be interoperable with ZX Net, but due to timing differences interoperability was found to be problematic.
The ZX Interface 1 was incompatible with some later ZX Spectrum models such as the +2A and +3, due to differences in ROM and in the expansion connector. It was therefore impossible to connect and use the Microdrive units with these later models. It did, however work with the original +2, although the much larger case made the interface an awkward fit.
Network
The device offered two network ports, allowing up to 64 ZX Spectrums to be daisy-chained using network leads up to long. The network, called ZX Net, used a bidirectional wire with a proprietary CSMA-like protocol. Data could be sent or received at either to or from a numbered workstation, or broadcast to all nodes, allowing one machine to act as a server.
Station number 0 is used to indicate broadcast. Data is transmitted in packets, each a maximum of 255 bytes long; the packet and the header are protected by a checksum. Character transmission uses 1 start bit, 8 data bits and 1 stop bit (the common 8-N-1 configuration).
Main commands:
FORMAT "n";<station number>
SAVE * "n";<stati |
https://en.wikipedia.org/wiki/Stooge%20sort | Stooge sort is a recursive sorting algorithm. It is notable for its exceptionally bad time complexity of =
The running time of the algorithm is thus slower compared to reasonable sorting algorithms, and is slower than bubble sort, a canonical example of a fairly inefficient sort. It is however more efficient than Slowsort. The name comes from The Three Stooges.
The algorithm is defined as follows:
If the value at the start is larger than the value at the end, swap them.
If there are 3 or more elements in the list, then:
Stooge sort the initial 2/3 of the list
Stooge sort the final 2/3 of the list
Stooge sort the initial 2/3 of the list again
It is important to get the integer sort size used in the recursive calls by rounding the 2/3 upwards, e.g. rounding 2/3 of 5 should give 4 rather than 3, as otherwise the sort can fail on certain data.
Implementation
Pseudocode
function stoogesort(array L, i = 0, j = length(L)-1){
if L[i] > L[j] then // If the leftmost element is larger than the rightmost element
swap(L[i],L[j]) // Then swap them
if (j - i + 1) > 2 then // If there are at least 3 elements in the array
t = floor((j - i + 1) / 3)
stoogesort(L, i, j-t) // Sort the first 2/3 of the array
stoogesort(L, i+t, j) // Sort the last 2/3 of the array
stoogesort(L, i, j-t) // Sort the first 2/3 of the array again
return L
}
Haskell
-- Not the best but equal to above
stoogesort :: (Ord a) => [a] -> [a]
stoogesort [] = []
stoogesort src = innerStoogesort src 0 ((length src) - 1)
innerStoogesort :: (Ord a) => [a] -> Int -> Int -> [a]
innerStoogesort src i j
| (j - i + 1) > 2 = src''''
| otherwise = src'
where
src' = swap src i j -- need every call
t = floor (fromIntegral (j - i + 1) / 3.0)
src'' = innerStoogesort src' i (j - t)
src''' = innerStoogesort src'' (i + t) j
src'''' = innerStoogesort src''' i (j - t)
swap :: (Ord a) => [a] -> Int -> Int -> [a]
swap src i j
| a > b = replaceAt (replaceAt src j a) i b
| otherwise = src
where
a = src !! i
b = src !! j
replaceAt :: [a] -> Int -> a -> [a]
replaceAt (x:xs) index value
| index == 0 = value : xs
| otherwise = x : replaceAt xs (index - 1) value
References
Sources
External links
Sorting Algorithms (including Stooge sort)
Stooge sort – implementation and comparison
Sorting algorithms
Comparison sorts
Articles with example pseudocode |
https://en.wikipedia.org/wiki/Mac%20Classic | Mac Classic may refer to:
Macintosh Classic, a model of Macintosh computer
Classic Environment, a compatibility layer for Mac OS 9 included in Mac OS X
Classic Mac OS, versions of Mac OS before Mac OS X |
https://en.wikipedia.org/wiki/Faraway%20Hill | Faraway Hill was the first soap opera broadcast on an American television network, airing on the DuMont Television Network on Wednesday nights at 9:00 PM between October 2 and December 18, 1946. A Variety article stated the Caples advertising agency bought time on DuMont for "experimentation purposes," and had "walked where other video programmers feared to tread," moving soap operas from radio to the "infant medium television."
The series' plot was based on a novel that David P. Lewis had begun, but never finished.
Synopsis
Karen St. John, a wealthy widowed New York City socialite, decides to spend time with her relatives, the Willow family, who live near the small town of Faraway Hill, in Kansas. St. John is attracted to Charlie White who is engaged to her niece, Louise Willow.
The series had an "all-seeing voice" that allowed viewers to know what the characters were thinking. A musical interlude would fade out so the voice could be heard. An example is: "Turn back, turn back, Karen St. John! Something inside you is sounding a warning – This is no place for you....How can you stay? You must leave in the morning…you cannot stay a summer."
The series ends with the death of Karen St. John, which upset the show's four hundred fans.
Jim Von Schilling, in his book, The Magic Window: American Television, 1939-1953, wrote, "Soap operas were popular on radio during the 1930s and 1940s; Faraway Hill simply brought the genre to television, where real arms were embraced, real tears shed, and where a card reading 'Continued Next Week' was held before the camera at each episode's climax."
Cast
Flora Campbell as Karen St. John, a wealthy young widow
Mel Brandt as Charlie White, who is engaged to Louise Willow
Ann Stell as Louise Willow, St. John's niece, and Charlie White's fiancé
Lorene Scott as Mrs. Willow, Louise's mother
Frederic Meyer as Mr. Willow, Louise's father
Cast members are listed in The Early Shows: A Reference Guide to Network and Syndicated Prime Time Television Series from 1944 to 1949.
Broadcast history
The series ran from October 2 to December 18, 1946. David P. Lewis, the writer and director, had a budget of around $300 an episode. The first episode originated from the basement of the Greenwich Village Wanamaker's department store.
The half-hour show was broadcast live, although filmed excerpts were interspersed, such as a train sequence in the first episode. Slides of scenes from previous shows were included in later episodes to bring viewers up to date with regard to plot elements which had previously transpired. A narrator gave Karen's thoughts as bridges between scenes.
In 1992, Lewis's obituary in the Los Angeles Times explained the program's short lifespan: "Lewis declared at the time that it was only an experiment. It never made a cent and had no commercials. ... He wanted, he said years later, not a successful series but to 'test the mind of the viewer.'"
Early commentary
A review in the October 23, 1946 issue of Varie |
https://en.wikipedia.org/wiki/Hour%20Glass%20%28TV%20series%29 | Hour Glass is the first regularly scheduled variety show shown on American network television. The Encyclopedia of Television noted that the program "is historically important because it exemplified the issues faced by networks, sponsors, and advertising agencies in television's formative years."
Distribution
Hour Glass was broadcast only on WNBT (now WNBC) in New York City from May 9, 1946, through November of that year, when distribution to NBC affiliates in Philadelphia and Schenectady began. From that time, the three-city network continued until March 1947.
Overview
Described as "the first [television] hour-long musical variety show", Hour Glass was sponsored by Standard Brands, promoting Chase and Sanborn coffee and Tenderleaf Tea. The program included comedians, musicians, entertaining films (such as a film of dance in South America), and a long, live commercial for the sponsor's products.
Such famous names as Doodles Weaver, Bert Lahr, Dennis Day, Anton Reiter, Jerry Colonna, Peggy Lee and Joe Besser appeared on the program. The first show was hosted by Evelyn Eaton (daughter of one of The Seven Little Eatons); Life surmised that NBC was adapting to a paradigm shift and making better use of the visual medium by hiring an attractive woman as master of ceremonies, as opposed to the more authoritative voices of men who typically commanded radio variety shows of the era.
On November 14, 1946, Edgar Bergen brought his ventriloquism act to the show. It was one of the first times that a major radio performer had appeared on television. Coincidentally, Standard Brands (via Chase and Sanborn) was the sponsor of Bergen's radio program.
Duration
The Columbia History of American Television attributed the program's short life to its cost and the lack of market penetration for television at the time, saying, "Standard Brands invested $200,000 in this series over its ten-month tenure at a time when that level of investment just couldn't be supported and sustained, leading to the Hour Glass'''s abbreviated run." Another factor was that James Petrillo, president of the American Federation of Musicians forbade musicians from performing on television without an agreement between the AFM and the networks, thus limiting directors and performers to use of recorded music and lip sync. A report in Life at the show's start noted that the show's audience at the time was estimated at 3,500 television sets watched by up to 20,000 viewers, a thousandth of the estimated 20,000,000 radio listeners nationwide that were hearing The Chase and Sanborn Hour in a given week.
Personnel
The show was co-hosted by Eddie Mayehoff and Helen Parrish. Bergen later became the host of the program. Edward Sobol was the producer. During the series' time on the air, a system of alternating writers was developed, giving "an individual writer two weeks in which to write a show instead of the weekly deadline."
Critical reception
A contemporary review in Life praised the individual p |
https://en.wikipedia.org/wiki/Osborne%20Vixen | The Osborne Vixen is a "luggable" portable computer announced by the Osborne Computer Corporation in November 1984, as a follow-up to their Osborne 1 and Osborne Executive system.
The Vixen has a 4 MHz Zilog Z80 microprocessor with 64 KB dynamic random-access memory (DRAM) and 4 KB EPROM. It has a 7-inch diagonal amber display that can show 24 lines by 80 columns of memory mapped video. It uses two 400 KB disk drives, utilizing double-density double-sided 5.25" diskettes. As a luggable, it weighs about 18 pounds. Contemporary advertising pointed out that it could fit under the seat in an airplane, with dimensions of 12 by 16 by 6 inches (321 by 413 by 159 mm).
When it was released, the Vixen had a retail price of $1298. Customers also had the option of purchasing an external 10 megabyte hard disk for $1495.
The Vixen used version 2.2 of the CP/M operating system. It was also bundled with a number of software packages: WordStar, the popular word processing package; SuperCalc, a spreadsheet; MBASIC, a programming language; Osboard, a graphics and drawing program; TurnKey, a system utility; Media Master, a data interchange program that allowed compatibility with over "200 other computers"; and Desolation, a game.
The Vixen was also known as the Osborne 4. It was developed and released after the bankruptcy of the Osborne Computer Corporation. An earlier system also called "Vixen" was never released. Due to technical problems with prototypes and the corporate bankruptcy, by the time the CP/M Vixen was introduced, it had already been made obsolete by MS-DOS IBM PC compatibles. A last ditch effort to design and market a fully IBM PC compatible produced three prototypes, but too late to save the company from bankruptcy.
Software
References
External links
Scans of a Vixen sales brochure
Portable computers
Z80-based computers |
https://en.wikipedia.org/wiki/BSGS | The initialism BSGS has two meanings, both related to group theory in mathematics:
Baby-step giant-step, an algorithm for solving the discrete logarithm problem
The combination of a base and strong generating set (SGS) for a permutation group |
https://en.wikipedia.org/wiki/Baby-step%20giant-step | In group theory, a branch of mathematics, the baby-step giant-step is a meet-in-the-middle algorithm for computing the discrete logarithm or order of an element in a finite abelian group by Daniel Shanks. The discrete log problem is of fundamental importance to the area of public key cryptography.
Many of the most commonly used cryptography systems are based on the assumption that the discrete log is extremely difficult to compute; the more difficult it is, the more security it provides a data transfer. One way to increase the difficulty of the discrete log problem is to base the cryptosystem on a larger group.
Theory
The algorithm is based on a space–time tradeoff. It is a fairly simple modification of trial multiplication, the naive method of finding discrete logarithms.
Given a cyclic group of order , a generator of the group and a group element , the problem is to find an integer such that
The baby-step giant-step algorithm is based on rewriting :
Therefore, we have:
The algorithm precomputes for several values of . Then it fixes an and tries values of in the right-hand side of the congruence above, in the manner of trial multiplication. It tests to see if the congruence is satisfied for any value of , using the precomputed values of .
The algorithm
Input: A cyclic group G of order n, having a generator α and an element β.
Output: A value x satisfying .
m ← Ceiling()
For all j where 0 ≤ j < m:
Compute αj and store the pair (j, αj) in a table. (See )
Compute α−m.
γ ← β. (set γ = β)
For all i where 0 ≤ i < m:
Check to see if γ is the second component (αj) of any pair in the table.
If so, return im + j.
If not, γ ← γ • α−m.
In practice
The best way to speed up the baby-step giant-step algorithm is to use an efficient table lookup scheme. The best in this case is a hash table. The hashing is done on the second component, and to perform the check in step 1 of the main loop, γ is hashed and the resulting memory address checked. Since hash tables can retrieve and add elements in time (constant time), this does not slow down the overall baby-step giant-step algorithm.
The space complexity of the algorithm is , while the time complexity of the algorithm is . This running time is better than the running time of the naive brute force calculation.
The Baby-step giant-step algorithm could be used by an eavesdropper to derive the private key generated in the Diffie Hellman key exchange, when the modulus is a prime number that is not too large. If the modulus is not prime, the Pohlig–Hellman algorithm has a smaller algorithmic complexity, and potentially solves the same problem.
Notes
The baby-step giant-step algorithm is a generic algorithm. It works for every finite cyclic group.
It is not necessary to know the order of the group G in advance. The algorithm still works if n is merely an upper bound on the group order.
Usually the baby-step giant-step algorithm is used for groups whose order is prime. If the order o |
https://en.wikipedia.org/wiki/OpenAL | OpenAL (Open Audio Library) is a cross-platform audio application programming interface (API). It is designed for efficient rendering of multichannel three-dimensional positional audio. Its API style and conventions deliberately resemble those of OpenGL. OpenAL is an environmental 3D audio library, which can add realism to a game by simulating attenuation (degradation of sound over distance), the Doppler effect (change in frequency as a result of motion), and material densities.
OpenAL aimed to originally be an open standard and open-source replacement for proprietary (and generally incompatible with one another) 3D audio APIs such as DirectSound and Core Audio, though in practice has largely been implemented on various platforms as a wrapper around said proprietary APIs or as a proprietary and vendor-specific fork. While the reference implementation later became proprietary and unmaintained, there are open source implementations such as OpenAL Soft available.
History
OpenAL was originally developed in 2000 by Loki Software to help them in their business of porting Windows games to Linux. After the demise of Loki, the project was maintained for a time by the free software/open source community, and implemented on NVIDIA nForce sound cards and motherboards. It was hosted (and largely developed) by Creative Technology until circa 2012.
Since 1.1 (2009), the sample implementation by Creative has turned proprietary, with the last releases in free licenses still accessible through the project's Subversion source code repository. However, OpenAL Soft is a widely used open source alternative and remains actively maintained and extended.
While the OpenAL charter says that there will be an "Architecture Review Board" (ARB) modeled on the OpenGL ARB, no such organization has ever been formed and the OpenAL specification is generally handled and discussed via email on its public mailing list.
The original mailing list, openal-devel hosted by Creative, ran from March 2003 to circa August 2012. Ryan C. Gordon, a Loki veteran who went on to develop Simple DirectMedia Layer, started a new mailing list and website at OpenAL.org in January 2014. As of February 2023, the list remains in use.
API structure and functionality
The general functionality of OpenAL is encoded in source objects, audio buffers and a single listener. A source object contains a pointer to a buffer, the velocity, position and direction of the sound, and the intensity of the sound. The listener object contains the velocity, position and direction of the listener, and the general gain applied to all sound. Buffers contain audio data in PCM format, either 8- or 16-bit, in either monaural or stereo format. The rendering engine performs all necessary calculations for distance attenuation, Doppler effect, etc.
The net result of all of this for the end user is that in a properly written OpenAL application, sounds behave quite naturally as the user moves through the three-dimensional space o |
https://en.wikipedia.org/wiki/Graph%20reduction | In computer science, graph reduction implements an efficient version of non-strict evaluation, an evaluation strategy where the arguments to a function are not immediately evaluated. This form of non-strict evaluation is also known as lazy evaluation and used in functional programming languages. The technique was first developed by Chris Wadsworth in 1971.
Motivation
A simple example of evaluating an arithmetic expression follows:
The above reduction sequence employs a strategy known as outermost tree reduction. The same expression can be evaluated using innermost tree reduction, yielding the reduction sequence:
Notice that the reduction order is made explicit by the addition of parentheses. This expression could also have been simply evaluated right to left, because addition is an associative operation.
Represented as a tree, the expression above looks like this:
This is where the term tree reduction comes from. When represented as a tree, we can think of innermost reduction as working from the bottom up, while outermost works from the top down.
The expression can also be represented as a directed acyclic graph, allowing sub-expressions to be shared:
As for trees, outermost and innermost reduction also applies to graphs. Hence we have graph reduction.
Now evaluation with outermost graph reduction can proceed as follows:
Notice that evaluation now only requires four steps. Outermost graph reduction is referred to as lazy evaluation and innermost graph reduction is referred to as eager evaluation.
Combinator graph reduction
Combinator graph reduction is a fundamental implementation technique for functional programming languages, in which a program is converted into a combinator representation which is mapped to a directed graph data structure in computer memory, and program execution then consists of rewriting parts of this graph ("reducing" it) so as to move towards useful results.
History
The concept of a graph reduction that allows evaluated values to be shared was first developed by Chris Wadsworth in his 1971 Ph.D. dissertation. This dissertation was cited by Peter Henderson and James H. Morris Jr. in 1976 paper, “A lazy evaluator” that introduced the notion of lazy evaluation. In 1976 David Turner incorporated lazy evaluation into SASL using combinators.
SASL was an early functional programming language first developed by Turner in 1972.
See also
Graph reduction machine
SECD machine
Notes
References
Further reading
Implementation of functional programming languages
Graph algorithms
Graph rewriting |
https://en.wikipedia.org/wiki/Transport%20Act%201947 | The Transport Act 1947 (10 & 11 Geo. 6. c. 49) was an Act of the Parliament of the United Kingdom. Under the terms of the Act, the railway network, long-distance road haulage and various other types of transport were nationalised and came under the administration of the British Transport Commission. The BTC was responsible to the Ministry of Transport for general transport policy, which it exercised principally through financial control of a number of executives set up to manage specified sections of the industry under schemes of delegation.
Overview
The Act was part of the nationalisation agenda of Clement Attlee's Labour government, and took effect from 1 January 1948. In Northern Ireland, the Ulster Transport Authority acted in a similar manner. The government also nationalised other means of transport such as: canals, sea and shipping ports, bus companies, and eventually, in the face of much opposition, road haulage. All of these transport modes, including British Railways, were brought under the control of a new body, the British Transport Commission (BTC).
The BTC was a part of a highly ambitious scheme to create a publicly owned, centrally planned, integrated transport system. In theory, the BTC was to co-ordinate different modes of transport, to co-operate and supplement each other instead of competing. This was to be achieved by means of fare and rate adjustments. In practice, very little integration between modes ever materialised.
Section 5 of the Act provided for the setting up of a number of executives within the BTC: the Railway Executive; the Docks and Inland Waterways Executive; the Road Transport Executive; and the London Transport Executive were to be created immediately, with the Hotels Executive to be set up at a later date. The same section allowed the number and names of these executives to be varied as necessary.
Road transport
The road haulage industry bitterly opposed nationalisation, and found allies in the Conservative Party. Once the Conservatives were elected in 1951, road haulage was soon privatised and deregulated, but the railways and buses remained regulated, and were left under the control of the British Transport Commission.
Railways
After the Second World War, the Big Four railway companies of the grouping era were effectively bankrupt, and the Act was intended to bring about some stability in transport policy. As part of that policy, British Railways was established to run the railways. (The Transport Act 1948 later transferred the lines in Northern Ireland formerly of the LMS, the Northern Counties Committee, to the Ulster Transport Authority.)
Shares in the railway companies were exchanged for British Transport Stock, with a guaranteed 3% return chargeable to the BTC, and were repayable after forty years.
The level of compensation paid has proved to be a matter of historical controversy. Some commentators, including The Economist and the London Stock Exchange stated that because the government based |
https://en.wikipedia.org/wiki/Delimiter | A delimiter is a sequence of one or more characters for specifying the boundary between separate, independent regions in plain text, mathematical expressions or other data streams. An example of a delimiter is the comma character, which acts as a field delimiter in a sequence of comma-separated values. Another example of a delimiter is the time gap used to separate letters and words in the transmission of Morse code.
In mathematics, delimiters are often used to specify the scope of an operation, and can occur both as isolated symbols (e.g., colon in "") and as a pair of opposing-looking symbols (e.g., angled brackets in ).
Delimiters represent one of various means of specifying boundaries in a data stream. Declarative notation, for example, is an alternate method that uses a length field at the start of a data stream to specify the number of characters that the data stream contains.
Overview
Delimiters may be characterized as field and record delimiters, or as bracket delimiters.
Field and record delimiters
Field delimiters separate data fields. Record delimiters separate groups of fields.
For example, the CSV format uses a comma as the delimiter between fields, and an end-of-line indicator as the delimiter between records:
fname,lname,age,salary
nancy,davolio,33,$30000
erin,borakova,28,$25250
tony,raphael,35,$28700
This specifies a simple flat file database table using the CSV file format.
Bracket delimiters
Bracket delimiters, also called block delimiters, region delimiters, or balanced delimiters, mark both the start and end of a region of text.
Common examples of bracket delimiters include:
Conventions
Historically, computing platforms have used certain delimiters by convention. The following tables depict a few examples for comparison.
Programming languages
(See also, Comparison of programming languages (syntax)).
Field and Record delimiters (See also, ASCII, Control character).
Delimiter collision
Delimiter collision is a problem that occurs when an author or programmer introduces delimiters into text without actually intending them to be interpreted as boundaries between separate regions. In the case of XML, for example, this can occur whenever an author attempts to specify an angle bracket character.
In most file types there is both a field delimiter and a record delimiter, both of which are subject to collision. In the case of comma-separated values files, for example, field collision can occur whenever an author attempts to include a comma as part of a field value (e.g., salary = "$30,000"), and record delimiter collision would occur whenever a field contained multiple lines. Both record and field delimiter collision occur frequently in text files.
In some contexts, a malicious user or attacker may seek to exploit this problem intentionally. Consequently, delimiter collision can be the source of security vulnerabilities and exploits. Malicious users can take advantage of delimiter collision in languages such as SQL and HT |
https://en.wikipedia.org/wiki/Prime7 | Prime7, formerly Prime Television and other names, was an Australian television network. Prime Television launched on 17 March 1962 as CBN-8 in Orange, and later expanded to cover regional New South Wales, Victoria and the Australian Capital Territory. It was initially an independent affiliate owned by Prime Media Group before the network, and its sister GWN7, were acquired by Seven West Media on 31 December 2021.
Prime7 along with GWN7 national broadcast facilities were based in Canberra, with playout facilities (since 2021) shared with hybrid-funded broadcaster SBS Television at a facility operated by Australian telecommunications provider Telstra. Seven West Media head office/administration is located in Pyrmont, Sydney.
History
Origins
Prime Television originally began as a group of separate stations and networks – Midstate Television in Orange, Dubbo and Griffith; RVN/AMV in Wagga Wagga and Albury; and 9-8 Television in Tamworth and Taree.
CBN-8 Orange first aired on 17 March 1962, followed by CWN-6 Dubbo on 1 December 1965. The two stations were both licensed to Country Television Services (also the owner of radio station 2GZ in Orange). CWN was a full-time relay of CBN—the first Australian television station to relay another. The two stations thus formed the country's first regional television network.
AMV-4 Albury launched on 7 September 1964 while RVN-2 Wagga Wagga began broadcasting on 19 June 1964, and MTN-9 Griffith began on 15 December 1965. The two stations merged in 1971 as the Riverina and North East Victoria Television Service Pty Ltd with the callsign RVN/AMV on air.
In northern New South Wales, NEN-9 Tamworth began transmission on 27 September 1965, with a relay in Armidale (NEN-1, later NEN-10) on 15 July 1966. ECN-8 Taree started on 27 May 1966. At one stage, ECN-8 was tied NRN-11 Coffs Harbour (now owned by WIN Corporation), however the two stations split. NEN later merged with ECN as 9-8 Television.
Television 6-8-9
As a result of the financial difficulties that many independent stations faced, MTN-9 joined CWN-6 and CBN-8 to form Television 6-8-9 in 1973. Relays were launched in Portland, Lithgow, Mudgee, Cobar, Kandos and Rylstone and Bathurst. In 1981, 6-8-9 changed its name to Midstate Television.
Colour television was introduced at the same time as the rest of the country, on 1 March 1975 – one of the single most expensive processes undertaken by CBN to date. The station was a prominent broadcaster of local sporting events including tennis and rugby. In 1979, a documentary titled Goin' Down The Road, about the 1978 National Rodeo Titles won the network a Logie award for an 'Outstanding Contribution by a Regional Station'.
Midstate produced a number of local programs, including the Weekend Report, Early Shift, Rural Roundup and Around the Schools. From 1968, CBN was able to access a Postmaster-General's Department microwave link for national news bulletins and major events.
Aggregation
Midstate Television was |
https://en.wikipedia.org/wiki/Altered%20Carbon | Altered Carbon is a 2002 cyberpunk novel by the English writer Richard K. Morgan. Set in a future in which interstellar travel and relative immortality is facilitated by transferring consciousnesses between bodies ("sleeves"), it follows the attempt of Takeshi Kovacs, a former U.N. elite soldier turned private investigator, to investigate a rich man's death. It is followed by the sequels Broken Angels and Woken Furies.
The book was adapted as a Netflix television series, also titled Altered Carbon, in 2018. In 2019 a graphic novel was created with Dynamite Comics.
Premise
In the future, humans have achieved virtual immortality. Most people have cortical stacks in their spinal columns that store their consciousness. If their body dies, their stack can be stored indefinitely. Their stacks can be downloaded into new bodies, or "sleeves", after death. Roman Catholics do not allow their stacks to be re-sleeved after death, as they believe that the soul goes to Heaven when they die, and so would not pass on to the new sleeve. This makes Catholics easy targets for murder, since killers know their victim may not be re-sleeved to testify. At the start of the novel, UN Resolution 653 is being debated. This proposition reverses precedent and would allow authorities to temporarily re-sleeve a deceased Catholic woman to testify in a murder trial. Dual-sleeving, or controlling two bodies with one personality, is strictly prohibited by U.N. law.
While most people can afford to get resleeved at the end of their lives, they are unable to update their bodies and most go through the full aging process each time, which discourages most from resleeving more than once or twice. Thus, while people can live indefinitely in theory, most choose not to. Only the wealthy are able to acquire replacement bodies on a continual basis. Those who have lived for multiple lifespans are called Meths, a reference to the Biblical figure Methuselah. The very rich are also able to keep copies of their minds in remote storage, which they update regularly. This ensures that even if their stack is destroyed, they can be re-sleeved. People who commit serious crimes are imprisoned "on stack". Their consciousness is preserved and stored virtually, sometimes for decades, while their body is sold to the highest bidder to be used for re-sleeving another person.
Numerous colony planets exist apart from Earth; many were previously inhabited by an extinct alien civilization referred to as the Elders. In order to deal with the challenges of interspace warfare, the U.N. created the Envoys. They are an elite military group with extensive training in re-sleeving and psychological modification, as well as combat. Envoys are so successful and dangerous that they are generally prohibited from holding elected office on any world.
Plot summary
On the colony planet of Harlan's World, Takeshi Kovacs and his partner Sarah Sachilowski, former Envoys who had returned to a life of crime, are killed by a U. |
https://en.wikipedia.org/wiki/The%20Al%20Franken%20Show | The Al Franken Show was the flagship talk show of the former talk radio network, Air America Radio. Hosted by Al Franken, it featured commentary and interviews arguing for liberal positions on the issues of the day, and comically poking fun at the George W. Bush Administration. Franken had been a comedian, satirist, and the author of several books, including the 2003 Lies and the Lying Liars Who Tell Them. He was a writer and performer on Saturday Night Live, where he usually teamed with fellow writer/performer Tom Davis.
The show began as The O'Franken Factor on March 31, 2004. Between January 3, 2006, and February 14, 2007, the show was recorded and broadcast from the 28th floor of the historic Foshay Tower in downtown Minneapolis, Minnesota. Prior to that date it was based in New York City. The final show was broadcast on February 14, 2007, the day Franken announced his candidacy for the United States Senate election of 2008. Franken's bid for the Senate was successful, with him serving there until resigning in 2018.
History
From the show's inception in March 2004 until October 7, 2005, the show was co-hosted by experienced journalist Katherine Lanpher. Lanpher left the show to write Leap Days, a memoir about her experiences moving to New York City. Lanpher did not rejoin the show because she did not wish to move again when Franken relocated to Minnesota. In November 2005, Franken told an audience in Berkeley, California that he would not seek a replacement for Lanpher. Her departure did not substantially change the content of the show.
When the show began, Franken signed a one-year contract. "I'm doing this because I want to use my energies to get Bush unelected. I'd be happy if the election of a Democrat ended the show", he said in an interview with The New York Times. Bush won a second term on November 2, 2004, but Franken said that the show would continue whether a Democrat or a Republican was in office.
Beginning on September 7, 2004, Sundance Channel broadcast a one-hour televised version of the show on weekdays. The show aired its last episode in November 2004. The channel inked a new contract with Franken and aired a second season of the show from June 6, 2005, until early November 2005.
On November 15, 2006, Air America affiliate KQKE-AM in San Francisco announced that Franken would leave Air America on December 10, as indicated by an audio clip posted on Whatamockery.com. After December 10, though Franken was still on Air America, KQKE began airing the Thom Hartmann Program in place of the Al Franken Show.
On his January 29, 2007, show, Franken announced that his last show on Air America Radio would be that Valentine's Day. Affiliates who carried the Franken show carried Thom Hartmann after that date, while XM Satellite Radio now carries Ed Schultz in that time slot. At the end of his final show, Franken announced his intention to run for the United States Senate from Minnesota.
The O'Franken Factor
Until July 12, 2004, the |
https://en.wikipedia.org/wiki/Digital%20control | Digital control is a branch of control theory that uses digital computers to act as system controllers.
Depending on the requirements, a digital control system can take the form of a microcontroller to an ASIC to a standard desktop computer.
Since a digital computer is a discrete system, the Laplace transform is replaced with the Z-transform. Since a digital computer has finite precision (See quantization), extra care is needed to ensure the error in coefficients, analog-to-digital conversion, digital-to-analog conversion, etc. are not producing undesired or unplanned effects.
Since the creation of the first digital computer in the early 1940s the price of digital computers has dropped considerably, which has made them key pieces to control systems because they are easy to configure and reconfigure through software, can scale to the limits of the memory or storage space without extra cost, parameters of the program can change with time (See adaptive control) and digital computers are much less prone to environmental conditions than capacitors, inductors, etc.
Digital controller implementation
A digital controller is usually cascaded with the plant in a feedback system. The rest of the system can either be digital or analog.
Typically, a digital controller requires:
Analog-to-digital conversion to convert analog inputs to machine-readable (digital) format
Digital-to-analog conversion to convert digital outputs to a form that can be input to a plant (analog)
A program that relates the outputs to the inputs
Output program
Outputs from the digital controller are functions of current and past input samples, as well as past output samples - this can be implemented by storing relevant values of input and output in registers. The output can then be formed by a weighted sum of these stored values.
The programs can take numerous forms and perform many functions
A digital filter for low-pass filtering
A state space model of a system to act as a state observer
A telemetry system
Stability
Although a controller may be stable when implemented as an analog controller, it could be unstable when implemented as a digital controller due to a large sampling interval. During sampling the aliasing modifies the cutoff parameters. Thus the sample rate characterizes the transient response and stability of the compensated system, and must update the values at the controller input often enough so as to not cause instability.
When substituting the frequency into the z operator, regular stability criteria still apply to discrete control systems. Nyquist criteria apply to z-domain transfer functions as well as being general for complex valued functions. Bode stability criteria apply similarly.
Jury criterion determines the discrete system stability about its characteristic polynomial.
Design of digital controller in s-domain
The digital controller can also be designed in the s-domain (continuous). The Tustin transformation can transform the continuous compensator |
https://en.wikipedia.org/wiki/Discrete%20system | In theoretical computer science, a discrete system is a system with a countable number of states. Discrete systems may be contrasted with continuous systems, which may also be called analog systems. A final discrete system is often modeled with a directed graph and is analyzed for correctness and complexity according to computational theory. Because discrete systems have a countable number of states, they may be described in precise mathematical models.
A computer is a finite-state machine that may be viewed as a discrete system. Because computers are often used to model not only other discrete systems but continuous systems as well, methods have been developed to represent real-world continuous systems as discrete systems. One such method involves sampling a continuous signal at discrete time intervals.
See also
Digital control
Finite-state machine
Frequency spectrum
Mathematical model
Sample and hold
Sample rate
Sample time
Z-transform
References
Automata (computation)
Models of computation
Signal processing |
https://en.wikipedia.org/wiki/Floptical | Floptical refers to a type of floppy disk drive that combines magnetic and optical technologies to store data on media similar to standard -inch floppy disks. The name is a portmanteau of the words "floppy" and "optical". It refers specifically to one brand of drive and disk system, but is also used more generically to refer to any system using similar techniques.
The original Floptical technology was announced in 1988 and introduced late in 1991 by Insite Peripherals, a venture funded company set up by Jim Adkisson, one of the key engineers behind the original -inch floppy disk drive development at Shugart Associates in 1976. The main shareholders were Maxell, Iomega and 3M.
Technical aspects
The technology involves reading and writing data magnetically, while optically aligning the read/write head in the drive using grooves in the disk being sensed by an infrared LED and sensor (a form of visual servo). The magnetic head touches the recording surface, as it does in a normal floppy drive. The optical servo tracks allow for an increase in the tracking precision of the magnetic head, from the usual 135 tracks per inch to tracks per inch. Floptical disks provide 21 MB of storage. The drive has a second set of read/write heads so that it can read from and write to standard 720 KB and 1.44 MB ( KB) disks as well.
To allow for a high degree of compatibility with existing SCSI host adapters, Floptical drives were designed to work as a standard floppy disk drive, and not as a removable hard disk. To ensure this, a "write lockout" feature was added in the firmware, effectively inhibiting writing (including any kind of formatting) of the media. It is possible to unlock the drive by issuing a SCSI Mode Sense Command, and Insite also issued EPROMs where this feature was not present.
At least two models were produced, one with a manual lever that mechanically ejected the disc from the drive, and another with a small pinhole into which a paperclip can be inserted, in case the device rejected or ignored SCSI eject commands.
Market performance
Insite licensed the floptical technology to a number of companies, including Matsushita, Iomega, Maxell/Hitachi and others. A number of these companies later formed the Floptical Technology Association, or FTA, to try to have the format adopted as a replacement of standard floppy disks.
Around 70,000 Insite Flopticals are believed to have been sold worldwide in the product's lifetime. Silicon Graphics used them in their SGI Indigo and SGI Indy series of computer workstations. It was also reported that Commodore International had selected the Insite Floptical for its Amiga 3000. However, this did not take place, and while Flopticals were installed in many Amiga systems, they were sold by either Insite, TTR Development or Digital Micronics (DMI), and not bundled by Commodore.
Iomega licensed the Floptical technology as early as 1989 and produced a compatible drive known as the Insider.
A few years later, a numbe |
https://en.wikipedia.org/wiki/Nslookup | nslookup (from "name server lookup") is a network administration command-line tool for querying the Domain Name System (DNS) to obtain the mapping between domain name and IP address, or other DNS records.
Overview
nslookup was a member of the BIND name server software. Early in the development of BIND 9, the Internet Systems Consortium planned to deprecate nslookup in favor of host and dig. This decision was reversed in 2004 with the release of BIND 9.3 and nslookup has been fully supported since then.
Unlike dig, nslookup does not use the operating system's local Domain Name System resolver library to perform its queries, and thus may behave differently. Additionally, vendor-provided versions may include output of other sources of name information, such as host files, and Network Information Service. Some behaviors of nslookup may be modified by the contents of resolv.conf.
The Linux version of nslookup was written by Andrew Cherenson.
The ReactOS version was developed by Lucas Suggs and is licensed under the GPL.
Usage
nslookup operates in interactive or non-interactive mode. When used interactively by invoking it without arguments or when the first argument is - (minus sign) and the second argument is a hostname or Internet address of a name server, the user issues parameter configurations or requests when presented with the nslookup prompt (>). When no arguments are given, then the command queries the default server. The - (minus sign) invokes subcommands which are specified on the command line and should precede nslookup commands. In non-interactive mode, i.e. when the first argument is a name or Internet address of the host being searched, parameters and the query are specified as command line arguments in the invocation of the program. The non interactive mode searches the information for a specified host using the default name server.
See also
dig, a utility interrogates DNS servers directly for troubleshooting and system administration purposes.
host is a simple utility for performing Domain Name System lookups.
List of DNS record types - possible types of records stored and queried within DNS
Root name server - top-level name servers providing top level domain name resolution
whois
BIND name server
References
Further reading
External links
Microsoft Windows
nslookup – Microsoft TechNet library
Using NSlookup.exe, Microsoft Knowledge Base
Unix-like OSs
nslookup source code in ISC Gitlab repository (Mozilla Public License)
DNS software
Internet Protocol based network software
OS/2 commands
Unix network-related software
Windows communication and services
Windows administration |
https://en.wikipedia.org/wiki/Leonid%20Khachiyan | Leonid Genrikhovich Khachiyan (; ; May 3, 1952April 29, 2005) was a Soviet and American mathematician and computer scientist.
He was most famous for his ellipsoid algorithm (1979) for linear programming, which was the first such algorithm known to have a polynomial running time. Even though this algorithm was shown to be impractical, it has inspired other randomized algorithms for convex programming and is considered a significant theoretical breakthrough.
Early life and education
Khachiyan was born on May 3, 1952, in Leningrad to Armenian parents Genrikh Borisovich Khachiyan, a mathematician and professor of theoretical mechanics, and Zhanna Saakovna Khachiyan, a civil engineer. His grandparents were Karabakh Armenians. He had two brothers: Boris and Yevgeniy (Eugene). His family moved to Moscow in 1961, when he was nine. He received a master's degree from the Moscow Institute of Physics and Technology. In 1978 he earned his Ph.D. in computational mathematics/theoretical mathematics from the Computer Center of the Soviet Academy of Sciences and in 1984 a D.Sc. in computer science from the same institution.
Career
Khachiyan began his career at the Soviet Academy of Sciences, working as a researcher at the academy's Computer Center in Moscow. He also worked as an adjunct professor at the Moscow Institute of Physics and Technology. In 1979 he stated: "I am a theoretical mathematician and I'm just working on a class of very difficult mathematical problems." Khachiyan immigrated to the United States in 1989. He first taught at Cornell University as a visiting professor. In 1990 he joined Rutgers University as a visiting professor. He became professor of computer science at Rutgers in 1992. By 2005, he held the position of Professor II at Rutgers, reserved for those faculty who have achieved scholarly eminence in their discipline.
Work on linear programming
Ellipsoid method
Khachiyan is best known for his four-page February 1979 paper that indicated how an ellipsoid method for linear programming can be implemented in polynomial time. The paper was translated into several languages and spread around the world unusually quickly. Authors of a 1981 survey of his work noted that it "has caused great excitement and stimulated a flood of technical papers" and was covered by major newspapers. It was originally published without proofs, which were provided by Khachiyan in a later paper published in 1980 and by Peter Gács and Laszlo Lovász in 1981. It was Gács and Lovász who first brought attention to Khachiyan's paper at the International Symposium on Mathematical Programming in Montreal in August 1979. It was further popularized when Gina Kolata reported it in Science Magazine on November 2, 1979.
Khachiyan's theory is considered a groundbreaking one that "helped advance the field of linear programming." Giorgio Ausiello noted that the method was not practical, "but it was a real breakthrough for the world of operations research and computer science, si |
https://en.wikipedia.org/wiki/Symbolic%20method | In mathematics, the symbolic method in invariant theory is an algorithm developed by Arthur Cayley, Siegfried Heinrich Aronhold, Alfred Clebsch, and Paul Gordan in the 19th century for computing invariants of algebraic forms. It is based on treating the form as if it were a power of a degree one form, which corresponds to embedding a symmetric power of a vector space into the symmetric elements of a tensor product of copies of it.
Symbolic notation
The symbolic method uses a compact, but rather confusing and mysterious notation for invariants, depending on the introduction of new symbols a, b, c, ... (from which the symbolic method gets its name) with apparently contradictory properties.
Example: the discriminant of a binary quadratic form
These symbols can be explained by the following example from Gordan. Suppose that
is a binary quadratic form with an invariant given by the discriminant
The symbolic representation of the discriminant is
where a and b are the symbols. The meaning of the expression (ab)2 is as follows. First of all, (ab) is a shorthand form for the determinant of a matrix whose rows are a1, a2 and b1, b2, so
Squaring this we get
Next we pretend that
so that
and we ignore the fact that this does not seem to make sense if f is not a power of a linear form.
Substituting these values gives
Higher degrees
More generally if
is a binary form of higher degree, then one introduces new variables a1, a2, b1, b2, c1, c2, with the properties
What this means is that the following two vector spaces are naturally isomorphic:
The vector space of homogeneous polynomials in A0,...An of degree m
The vector space of polynomials in 2m variables a1, a2, b1, b2, c1, c2, ... that have degree n in each of the m pairs of variables (a1, a2), (b1, b2), (c1, c2), ... and are symmetric under permutations of the m symbols a, b, ....,
The isomorphism is given by mapping aa, bb, .... to Aj. This mapping does not preserve products of polynomials.
More variables
The extension to a form f in more than two variables x1, x2, x3,... is similar: one introduces symbols a1, a2, a3 and so on with the properties
Symmetric products
The rather mysterious formalism of the symbolic method corresponds to embedding a symmetric product Sn(V) of a vector space V into a tensor product of n copies of V, as the elements preserved by the action of the symmetric group. In fact this is done twice, because the invariants of degree n of a quantic of degree m are the invariant elements of SnSm(V), which gets embedded into a tensor product of mn copies of V, as the elements invariant under a wreath product of the two symmetric groups. The brackets of the symbolic method are really invariant linear forms on this tensor product, which give invariants of SnSm(V) by restriction.
See also
Umbral calculus
References
Footnotes
Further reading
pp. 32–7, "Invariants of n-ary forms: the symbolic method. Reprinted as
Algebra
Invariant theory |
https://en.wikipedia.org/wiki/Beos | Beos may refer to:
BeOS, an operating system
Brain Electrical Oscillation Signature Profiling
Beos Station, rail station in Indonesia
See also
BEO (disambiguation) |
https://en.wikipedia.org/wiki/The%20Twentieth%20Century | The Twentieth Century was a documentary television program that ran on the CBS network from 1957 until 1966. The series produced 112 historical compilation films and 107 "originally photographed documentaries" or contemporary documentaries, each running a half-hour. Productions were narrated by Walter Cronkite and drew on the resources of CBS News. The compilations mixed newsreel footage and eyewitness interviews, focusing on great events, unfamiliar historical episodes, and biographical portraits, including contemporary men in the arts, sciences, law, and politics. As the series progressed, the compilation films were gradually outnumbered by the contemporary documentaries, similar to the work being done in the CBS Reports series, but often treating social and political change overseas rather than in the U.S. Popular and critically-acclaimed, audiences averaged 13 million viewers a week, and the series was an influential forerunner to many subsequent television documentary series.
The program was sponsored during its entire run by the Prudential Insurance Company, whose Rock of Gibraltar symbol was often the backdrop for the opening and closing credits. But the company approved the topics and limited the treatment of issues it felt to be potentially upsetting to a large audience, particularly social and religious subjects. Prudential -– and the Department of Defense which provided film footage and cooperation for many episodes—also wanted an uncritical portrayal of the U.S. military. Prudential withdrew sponsorship after the ninth season when sports programming seriously cut into the number of its 6 pm Sunday timeslots, and contemporary subjects came to dominate productions.
The series’ theme music, in which a ragtime-tinged orchestral cacophony abruptly changes to a triumphal contemporary march, was famous in its day. Aired in several versions, it was written by the erstwhile avant-garde composer George Antheil and is arguably his most heard work. (Curiously, the theme never had an on-screen credit and has been available only on copies of the original broadcasts.) Many episodes had original scores commissioned from a wide range of contemporary classical and film composers, including Antheil, Auric, Creston, Gould, Hovhaness, Kay, Kubik, Milhaud, Nascimbene, Rosenthal, Shapero, Siegmeister, Tcherepnin, and Waxman. Alfredo Antonini composed half the scores and led the CBS Orchestra in performances.
Successor series
The series was replaced in 1967 with a spin-off, The 21st Century. Produced by many of The Twentieth Century team and narrated by Cronkite, the new series focused on what humankind could shape and expect by examining aspects of the future already evident in the present. It was sponsored by Union Carbide ("The Discovery Company"). The 21st Century ran only three seasons (its final broadcast was on 4 January 1970). The reason given was that the writers had run out of topics, but CBS may have wanted a more commercially succes |
https://en.wikipedia.org/wiki/Lookahead | Lookahead or Look Ahead may refer to:
A parameter of some combinatorial search algorithms, describing how deeply the graph representing the problem is explored
A parameter of some parsing algorithms; the maximum number of tokens that a parser can use to decide which rule to use
In dynamic range compression, a signal processing design to avoid compromise between slow attack rates that produce smooth-sounding gain changes, and fast attack rates capable of catching transients
Look-ahead (backtracking), a subprocedure that attempts to predict the effects of choosing a branching variable to evaluate or one of its values
Lookahead carry unit, a logical unit in digital circuit design used to decrease calculation time in adder units
Look Ahead, a charitable housing association in London
In regular expressions, an assertion to match characters after the current position
Education
Look Ahead, 1990s English as a foreign language multimedia classroom project by BBC English and other organisations
Music
Look Ahead (Pat Boone album), 1968
Look Ahead, 1992 album by Gerald Veasley
Look Ahead, 1995 album by Danny Tenaglia
"Look Ahead", 1992 song by Pat Metheny on the album Secret Story
"Look Ahead", 2014 song by rapper Future, on the album Honest (Future album)
See also
Looking Ahead (disambiguation) |
https://en.wikipedia.org/wiki/IBM%201130 | The IBM 1130 Computing System, introduced in 1965, was IBM's least expensive computer at that time. A binary 16-bit machine, it was marketed to price-sensitive, computing-intensive technical markets, like education and engineering, succeeding the decimal IBM 1620 in that market segment. Typical installations included a 1 megabyte disk drive that stored the operating system, compilers and object programs, with program source generated and maintained on punched cards. Fortran was the most common programming language used, but several others, including APL, were available.
The 1130 was also used as an intelligent front-end for attaching an IBM 2250 Graphics Display Unit, or as remote job entry (RJE) workstation, connected to a System/360 mainframe.
Description
The total production run of the 1130 has been estimated at 10,000.
The 1130 holds a place in computing history because it (and its non-IBM clones) gave many people their first direct interaction with a computer. Its price-performance ratio was good and it notably included inexpensive, removable disk storage, with reliable, easy-to-use software that could be in several high-level languages. The low price (from around $32,000 or $41,000 with disk drive) and well-balanced feature set enabled interactive "open shop" program development.
The IBM 1130 uses the same electronics packaging, called Solid Logic Technology (SLT), used in System/360. It has a 16-bit binary architecture, as do later minicomputers like the PDP-11 and Data General Nova.
The address space is 15 bits, limiting the 1130 to words () of memory. The 1130 uses magnetic-core memory, which the processor addresses on word boundaries, using direct, indirect, and indexed addressing modes.
Models
IBM implemented five models of the 1131 Central Processing Unit, the primary processing component of the IBM 1130. The Model 1 through Model 5 describe the core memory cycle time, as well as the model's ability to have disk storage. A letter A through D appended to the model number indicates the amount of core memory installed.
IBM 1131 Central Processing Unit weighs about 760/1050 lb (345/477 kg).
The Model 4 was a lower-priced product with a 5.6 μs cycle time. Some purchasers of performance upgrades observed that the field adjustment to achieve the improvement was surprisingly trivial.
The IBM 1132 printer relies on the 1130 processor rather than internal logic to determine when to fire the print wheels as they rotated. Printers for the Model 4 run more slowly, but the slower processor still can not keep up with it. The hardware manual discloses that when the Model 4 was servicing the two highest-level interrupts (the level 0 card-reader column interrupt or the level 1 printer interrupt), it ran at the faster 3.6 μs cycle time. Some users of the Model 4 would write a phony printer driver that did not dismiss the printer interrupt, in order to benefit from the higher processor speed. However, lower-level interrupts are disabled duri |
https://en.wikipedia.org/wiki/IBM%201800%20Data%20Acquisition%20and%20Control%20System | The IBM 1800 Data Acquisition and Control System (DACS) was a process control variant of the IBM 1130 with two extra instructions (CMP and DCM), extra I/O capabilities, 'selector channel like' cycle-stealing capability and three hardware index registers.
IBM announced and introduced the 1800 Data Acquisition and Control System on November 30, 1964, describing it as "a computer that can monitor an assembly line, control a steel-making process or analyze the precise status of a missile during test firing."
Overview
Unlike the 1130, which was a desk-like unit, the 1800 is packaged in 6 foot high, EIA Standard 19 inch racks, which are somewhat taller than the racks used by S/360 systems of the same vintage, but the internal gates and power supplies were very much the same.
The IBM 1500 instructional system was introduced by IBM on March 31, 1966, and was based on an IBM 1130 or IBM 1800 computer. It supported up to 32 student work stations, each with a variety of audiovisual capabilities.
Two 1800s with automatic switchover between them powered each IBM 1750, 2750 and 3750 Switching System.
Components
The IBM 1800 DACS consisted of:
D/A (Digital-to-Analog) Converter
A/D (Analog-to-Digital) Converter
IBM 1801 Processor Controller, with operator's panel
IBM 1802 Processor Controller, with operator's panel, to include adapters for 2401/2402 Magnetic Tape Units.
IBM 1803 Core Storage Addition
IBM 1826 I/O Expansion Chassis (used for communications I/O, System/360 channels, 279x)
IBM 1828 Process Expansion Unit (used for additional D/A or A/D converters, or to hold 1851 and/or 1854 multiplexors; there was an RPQ for a remote 1828 unit)
IBM 1810 Disk (equivalent to 2310 on IBM 1130)
IBM 1816 Printer Keyboard (System Printer)
IBM 1851 Reed Relay Analog Multiplexor
IBM 1854 Solid State Analog Multiplexor
IBM 1894 generic model number for many 1800 RPQ hardware features, which inter alia, included support for IBM 109x data entry devices)
IBM 1053 Printer
IBM 1054 Paper Tape Reader Unit
IBM 1055 Paper Tape Punch Unit
IBM 1442 Card Reader/Punch Unit
IBM 1443 Printer
IBM 1627 Plotter
IBM 2401 or 2402 Magnetic Tape Unit (its adapter included in IBM 1802)
IBM 2311 DASD (attached via an IBM 2841 Control Unit, latter attached to a channel in the IBM 1826), the MPX operating system could map two 1810 disks per 2311, the 1810 drive mapping being seen as a Format 5 DSCB to S/360 OS)
IBM 2260 CRT (attached via an IBM 2848 Control Unit, latter attached to a channel in the IBM 1826)
IBM 2790 Data Communication System, one of the earliest token ring type local area networks were attached and controlled by the IBM 1800.
Use
The IBM 1800 systems were used mainly in the process industry plants worldwide.
In June 2010 the last four operating IBM 1800s operating at Pickering Nuclear Generating Station in Pickering, Ontario, Canada were removed from service. Pickering is still using four ES-1800 computers which are IBM 1800 hardware emulators buil |
https://en.wikipedia.org/wiki/Distcc | In software development, distcc is a tool for speeding up compilation of source code by using distributed computing over a computer network. With the right configuration, distcc can dramatically reduce a project's compilation time.
It is designed to work with the C programming language (and its derivatives like C++ and Objective-C) and to use GCC as its backend, though it provides varying degrees of compatibility with the Intel C++ Compiler and Sun Microsystems' Sun Studio Compiler Suite. Distributed under the terms of the GNU General Public License, distcc is free software.
Design
distcc is designed to speed up compilation by taking advantage of unused processing power on other computers. A machine with distcc installed can send code to be compiled across the network to a computer which has the distccd daemon and a compatible compiler installed.
distcc works as an agent for the compiler. A distcc daemon has to run on each of the participating machines. The originating machine invokes a preprocessor to handle header files, preprocessing directives (such as #ifdef) and the source files and sends the preprocessed source to other machines over the network via TCP either unencrypted or using SSH. Remote machines compile those source files without any local dependencies (such as libraries, header files or macro definitions) to object files and send them back to the originator for further compilation.
distcc version 3 supports a mode (called pump mode) in which included header files are sent to the remote machines,
so that preprocessing is also distributed.
Related software
distcc was an option for distributed builds in versions of Apple's Xcode development suite prior to 4.3, but has been removed.
Goma
Goma is a similar tool made by Google to replace distcc & ccache in compiling chromium.
Ccache
ccache is another tool aimed to reduce the compilation time by caching the output from the same input source files. ccache can also use distcc as its backend, providing distributed compiling if it is not already cached by using the CCACHE_PREFIX environment variable.
Icecream
icecream was created by SUSE based on distcc. Like distcc, icecream takes compile jobs from a build and distributes it among remote machines allowing a parallel build. But unlike distcc, icecream uses a central server that dynamically schedules the compile jobs to the fastest free server.
See also
Compile farm
FlowTracer
IncrediBuild
Electric Cloud
References
External links
google distcc pump mode
Comparison of related system
DMUCS – a Distributed Multi-User Compilation System
DistCC Enterprise Load Balancer
Compiling tools
Free computer programming tools
Cross-platform software
Unix programming tools |
https://en.wikipedia.org/wiki/CSN | CSN may refer to:
Companies
CSN Stores, former name of Wayfair, American e-commerce company
CSN International (Christian Satellite Network), religious radio broadcaster based on radio station KAWZ in Twin Falls, Idaho
Centrala Studiestödsnämnden, Swedish national student loans and grants authority
Columbus Sports Network (WCSN-LD), low-power television station in Columbus, Ohio
Comcast SportsNet, former name of NBC Sports Regional Networks
Comic Shop News, free weekly newspaper distributed throughout comic book specialty stores
Companhia Siderúrgica Nacional, Brazilian steel maker
Music
Crosby, Stills & Nash, an American folk rock supergroup
CSN (album), 1977
CSN (box set), 1991
Transport
CSN, National Rail station code for Chessington North railway station, England
Changsha South railway station, China Railway pinyin code CSN
China Southern Airlines, China
Other uses
Canaan Smith-Njigba (born 1999), American baseball player
Cell Signaling Networks
COP9 signalosome (CSN), a protein complex
CSN2
COP9 signalosome complex subunit 3 (CSN3)
Coláiste an Spioraid Naoimh, a secondary school in Cork City, Ireland
College of Southern Nevada, a community college located in Clark County
Comunidad Sudamericana de Naciones, Union of South American Nations
CSN.1, Concrete Syntax Notation, a telecommunications and computer networking standard
Confederate States Navy
Confédération des syndicats nationaux
Carlton Sports Network, a sports channel in Sri Lanka
Czech technical standard (ČSN) |
https://en.wikipedia.org/wiki/Oregon%20Public%20Broadcasting | Oregon Public Broadcasting (OPB) is the primary television and radio public broadcasting network for most of the U.S. state of Oregon as well as southern Washington. OPB consists of five full-power television stations, dozens of VHF or UHF translators, and over 20 radio stations and frequencies. Broadcasts include local and regional programming as well as television programs from the Public Broadcasting Service (PBS) and American Public Television (APT), and radio programs from National Public Radio (NPR), American Public Media (APM), Public Radio Exchange (PRX), and the BBC World Service, among other distributors. Its headquarters and television studios are located in Portland.
OPB is also a major producer of television programming for national broadcast on PBS and Create through distributors like APT, with shows such as History Detectives, Barbecue America, Foreign Exchange, Rick Steves' Europe, and travel shows hosted by Art Wolfe.
, OPB had over one million viewers throughout its region and an average of over 380,000 radio listeners each week. The part of southwestern Oregon not served by OPB is served by KLCC radio, Jefferson Public Radio, and Southern Oregon PBS.
History
20th century
OPB traces its roots to January 23, 1923, when KFDJ signed on from the Corvallis campus of Oregon Agricultural College (now Oregon State University). The radio station's call letters were changed to KOAC on December 11, 1925. In 1932, KOAC became a service of the Oregon State Board of Higher Education General Extension Division
KOAC Radio won OPB's first Peabody Award when it was recognized for Outstanding Public Service by a Local Station for a 1942 program called Our Hidden Enemy, Venereal Disease.
From 1923 to 1981, the Oregon State University campus served as the radio and later TV base of operations. On October 7, 1957, the station began TV operations as KOAC-AM-TV and the university constructed KOAC's first TV studios inside Gill Coliseum. Faculty at Oregon State University used the studios to broadcast extension courses across the state. Originally known as Oregon Educational Broadcasting, it became the Oregon Educational and Public Broadcasting Service (OEPBS) in 1971. In 1981, OEPBS was spun off from the Oregon State System of Higher Education and became a separate state agency, Oregon Public Broadcasting. The former Portland satellites, KOAP-FM-TV, became the flagship stations.
In addition to the studio and transmission facilities in Corvallis, there was another production studio located on the top floor of Villard Hall at the University of Oregon in Eugene that was connected by microwave link. Up until 1965, all programs from the Eugene studio were live, since they did not get any video recording equipment until then. During that time period, the Eugene studio operated two RCA TK31 cameras.
KOAP-TV in Portland signed on the air February 6, 1961; it became the flagship of OPB in 1981 and changed its call letters to KOPB-TV on February 15, 19 |
https://en.wikipedia.org/wiki/Piconet | A piconet is an ad hoc network that links a wireless user group of devices using Bluetooth technology protocols. A piconet consists of two or more devices occupying the same physical channel (synchronized to a common clock and hopping sequence). It allows one master device to interconnect with up to seven active slave devices. Up to 255 further slave devices can be inactive, or parked, which the master device can bring into active status at any time, but an active station must go into parked first.
Some examples of piconets include a cell phone connected to a computer, a laptop and a Bluetooth-enabled digital camera, or several PDAs that are connected to each other.
Overview
A group of devices are connected via Bluetooth technology in an ad hoc fashion. A piconet starts with two connected devices, and may grow to eight connected devices. Bluetooth communication always designates one of the Bluetooth devices as a main controlling unit or master unit. Other devices that follow the master unit are slave units. This allows the Bluetooth system to be non-contention based (no collisions). This means that after a Bluetooth device has been added to the piconet, each device is assigned a specific time period to transmit and they do not collide or overlap with other units operating within the same piconet.
Piconet range varies according to the class of the Bluetooth device. Data transfer rates vary between about 200 and 2100 kilobits per second.
Because the Bluetooth system hops over 79 channels, the probability of interfering with another Bluetooth system is less than 1.5%. This allows several Bluetooth piconets to operate in the same area at the same time with minimal interference.
See also
Personal area network (PAN)
Scatternet
IEEE 802.15
Further reading
Bluetooth |
https://en.wikipedia.org/wiki/Scatternet | A scatternet is a type of ad hoc computer network consisting of two or more piconets. The terms "scatternet" and "piconet" are typically applied to Bluetooth wireless technology.
Description
A piconet is the type of connection that is formed between two or more Bluetooth-enabled devices such as modern cell phones. Bluetooth enabled devices are "peer units" in that they are able to act as either master or slave. However, when a piconet is formed between two or more devices, one device takes the role of the 'master', and all other devices assume a 'slave' role for synchronization reasons. Piconets have a 7 member address space (3 bits, with zero reserved for broadcast), which limits the maximum size of a piconet to 8 devices, i.e. 1 master and 7 slaves.
A scatternet is a number of interconnected piconets that supports communication between more than 8 devices. Scatternets can be formed when a member of one piconet (either the master or one of the slaves) elects to participate as a slave in a second, separate piconet. The device participating in both piconets can relay data between members of both ad hoc networks. However, the basic Bluetooth protocol does not support this relaying - the host software of each device would need to manage it. Using this approach, it is possible to join together numerous piconets into a large scatternet, and to expand the physical size of the network beyond Bluetooth's limited range.
Currently there are very few actual implementations of scatternets due to limitations of Bluetooth and the MAC address protocol. However, there is a growing body of research being conducted with the goal of developing algorithms to efficiently form scatternets.
Future applications
Scatternets have the potential to bring the interconnectivity of the Internet to the physical world through wireless devices. A number of companies have attempted to launch social networking and dating services that leverage early scatternet implementations (see Bluedating). Scatternets can also be used to enable ad hoc communication and interaction between autonomous robots and other devices.
Research
Several papers exist that propose algorithms for scatternet formation, and many different approaches have been simulated in both academic and corporate R&D environments. Some early experiments with large scatternets can be found at ETH Zurich in the BTnode project.
In 2008, a student at University College Cork, Ireland, developed a scatternet-based application in the Java programming language, using the JSR-82 library. This application's main purpose is to facilitate parallel computations over Bluetooth scatternets, using an MPI-style message passing paradigm. Although it only runs on the emulation environment provided by Sun's Wireless Toolkit, it is capable of creating a scatternet of up to 15 devices and routing a message through the network.
In 2006, a student at the University of Technology, Iraq, developed an on-demand peer-to-peer scatternet routing a |
https://en.wikipedia.org/wiki/NMT | NMT may refer to:
Science and technology
Nordic Mobile Telephone, an analogue mobile phone system
Neurologic Music Therapy
Neural machine translation
Network management protocols, in the CANopen communication protocol
3-hydroxy-16-methoxy-2,3-dihydrotabersonine N-methyltransferase, an enzyme
N-Methyltryptamine, an alkaloid similar to dimethyltryptamine
Non-invasive micro-test technology, a scientific research technology
Other
Needham Market railway station, UK National Rail code
New Measurement Train, UK specialised testing train
New Mexico Institute of Mining and Technology, a state university in New Mexico
Nuremberg Military Tribunals, of Nazis after World War II |
https://en.wikipedia.org/wiki/Data%20link%20connection%20identifier | A data link connection identifier (DLCI) is a Frame Relay 10-bit-wide link-local virtual circuit identifier used to assign frames to a specific PVC or SVC. Frame Relay networks use DLCIs to statistically multiplex frames. DLCIs are preloaded into each switch and act as road signs to the traveling frames.
The standard allows the existence of 1024 DLCIs. DLCI 0 is reserved for the ANSI/q993a LMI standard—only numbers 16 to 976 are usable for end-user equipment. DLCI 1023 is reserved for Cisco LMI, however, numbers 16 to 1007 are usable.
In summary, if using Cisco LMI, numbers from 16 to 1007 are available for end-user equipment. The rest are reserved for various management purposes.
DLCI are Layer 2 Addresses that are locally significant. No two devices have the same DLCI mapped to its interface in one frame relay cloud.
References
Link protocols
Frame Relay |
https://en.wikipedia.org/wiki/TDC | TDC may refer to:
Organisations
Hong Kong Trade Development Council
Taiwan Design Center, an art organization based in Taipei, Taiwan
TDC A/S, a Danish telecommunications company
Teradata Corporation (U.S. ticker symbol)
Texas Department of Criminal Justice, formerly the Texas Department of Corrections
Type Directors Club, an international organization specialising in typography
Theta Delta Chi, a social fraternity founded at Union College, New York, US
The Discovery Channel, former name of Discovery Channel
Places
Tristan da Cunha, both a remote group of volcanic islands in the south Atlantic Ocean and the main island of that group
Tokyo Dome City, an entertainment complex in Tokyo, Japan
Toronto-Dominion Centre, a cluster of buildings in Toronto, Ontario, Canada
Technology
Time-to-digital converter, a device in signal processing
Top dead center, the position farthest from the crankshaft of a piston in a reciprocating engine, see Dead centre (engineering)
Torpedo Data Computer, a piece of naval technology
Other uses
Total delivery cost, the amount of money it takes for a company to manufacture and deliver a product
Trophée des Champions, a French association football trophy
The Death Cure, a science fiction novel by American writer James Dashner
Trainee Detective Constable, the most junior British police Criminal Investigation Department (CID) rank; See Police ranks of the United Kingdom |
https://en.wikipedia.org/wiki/Peter%20Norvig | Peter Norvig (born December 14, 1956) is an American computer scientist and Distinguished Education Fellow at the Stanford Institute for Human-Centered AI. He previously served as a director of research and search quality at Google. Norvig is the co-author with Stuart J. Russell of the most popular textbook in the field of AI: Artificial Intelligence: A Modern Approach used in more than 1,500 universities in 135 countries.
Education
Norvig received a Bachelor of Science in applied mathematics from Brown University and a Ph.D. in computer science from the University of California, Berkeley.
Career and research
Norvig is a councilor of the Association for the Advancement of Artificial Intelligence and co-author, with Stuart J. Russell, of Artificial Intelligence: A Modern Approach, now the leading college text in the field. He was head of the Computational Sciences Division (now the Intelligent Systems Division) at NASA Ames Research Center, where he oversaw a staff of 200 scientists performing NASA's research and development in autonomy and robotics, automated software engineering and data analysis, neuroengineering, collaborative systems research, and simulation-based decision-making. Before that he was chief scientist at Junglee, where he helped develop one of the first Internet comparison-shopping services; chief designer at Harlequin Inc.; and senior scientist at Sun Microsystems Laboratories.
Norvig has served as an assistant professor at the University of Southern California and as a research faculty member at Berkeley. He has over fifty publications in various areas of computer science, concentrating on artificial intelligence, natural language processing, information retrieval and software engineering, including the books Artificial Intelligence: A Modern Approach, Paradigms of AI Programming: Case Studies in Common Lisp, Verbmobil: A Translation System for Face-to-Face Dialog, and Intelligent Help Systems for UNIX.
Norvig is one of the creators of JScheme. Norvig is listed under "Academic Faculty & Advisors" for the Singularity University. In 2011, Norvig worked with Sebastian Thrun to develop a popular online course in Artificial Intelligence that had more than 160,000 students enrolled. He also teaches an online course via the Udacity platform.
Selected publications and presentations
By 2022, Artificial Intelligence: A Modern Approach, which Norvig first co-authored with Stuart J. Russell in 1995, was the leading textbook in the field used by over 1400 schools globally.
In 2001, Norvig published a short article titled Teach Yourself Programming in Ten Years, arguing against the fashionable introductory programming textbooks that purported to teach programming in days or weeks. The article was widely shared and discussed, and has attracted contributed translations to over 20 languages.
Norvig is also known for his 2003 Gettysburg Powerpoint Presentation, a satire about bad presentation practices using Abraham Lincoln's famous Get |
https://en.wikipedia.org/wiki/Artificial%20Intelligence%3A%20A%20Modern%20Approach | Artificial Intelligence: A Modern Approach (AIMA) is a university textbook on artificial intelligence, written by Stuart J. Russell and Peter Norvig. It was first published in 1995 and the fourth edition of the book was released on 28 April 2020. It is used in over 1400 universities worldwide and has been called "the most popular artificial intelligence textbook in the world". It is considered the standard text in the field of artificial intelligence.
The book is intended for an undergraduate audience but can also be used for graduate-level studies with the suggestion of adding some of the primary sources listed in the extensive bibliography. Programs in the book are presented in pseudo code with implementations in Java, Python, Lisp, JavaScript and Scala available online. There are also unsupported implementations in Prolog, C++, C#, and several other languages.
Editions
1st 1995, red cover
2nd 2003, green cover
3rd 2009, blue cover
4th 2020, purple cover
References
External links
1995 non-fiction books
2003 non-fiction books
2009 non-fiction books
2020 non-fiction books
Artificial intelligence publications
Cognitive science literature
Computer science textbooks
English-language books
Robotics books
Prentice Hall books |
https://en.wikipedia.org/wiki/Stuart%20J.%20Russell | Stuart Jonathan Russell (born 1962) is a British computer scientist known for his contributions to artificial intelligence (AI). He is a professor of computer science at the University of California, Berkeley and was from 2008 to 2011 an adjunct professor of neurological surgery at the University of California, San Francisco. He holds the Smith-Zadeh Chair in Engineering at University of California, Berkeley. He founded and leads the Center for Human-Compatible Artificial Intelligence (CHAI) at UC Berkeley. Russell is the co-author with Peter Norvig of the authoritative textbook of the field of AI: Artificial Intelligence: A Modern Approach used in more than 1,500 universities in 135 countries.
Education and early life
Russell was born in Portsmouth, England. He attended St Paul's School, London, where he was 1st scholar. He studied physics at Wadham College, Oxford, and was awarded his Bachelor of Arts degree with first-class honours in 1982. He moved to the United States to complete his PhD in computer science at Stanford University in 1986 for research on inductive reasoning and analogical reasoning supervised by Michael Genesereth. His PhD was supported by a NATO studentship from the UK Science and Engineering Research Council.
Career and research
After his 1986 PhD, he joined the faculty of the University of California, Berkeley as a professor of computer science. From 2008 to 2011 he also held an appointment as adjunct professor of Neurological Surgery at the University of California, San Francisco, where he pursued research in computational physiology and intensive-care unit monitoring. He is also an Honorary Fellow at Wadham College, Oxford.
His research in the area of Artificial Intelligence (AI) includes contributions to machine learning, probabilistic reasoning, knowledge representation, planning, real-time decision making, multitarget tracking, computer vision, and inverse reinforcement learning. He has also been an active participant in the movement to ban the manufacture and use of autonomous weapons.
In 2016, he founded the Center for Human-Compatible Artificial Intelligence at UC Berkeley, with co-principal investigators Pieter Abbeel, Anca Dragan, Tom Griffiths, Bart Selman, Joseph Halpern, Michael Wellman and Satinder Singh Baveja. Russell has published several hundred conference and journal articles as well as several books, including The Use of Knowledge in Analogy and Induction and Do the Right Thing: Studies in Limited Rationality (with Eric Wefald). Along with Peter Norvig, he is the author of Artificial Intelligence: A Modern Approach, a textbook used by over 1,500 universities in 135 countries. He is on the Scientific Advisory Board for the Future of Life Institute and the advisory board of the Centre for the Study of Existential Risk.
In 2017 he collaborated with the Future of Life Institute to produce a video, Slaughterbots, about swarms of drones assassinating political opponents, and presented this to a United N |
https://en.wikipedia.org/wiki/1worldspace | 1worldspace, known for most of its existence simply as WorldSpace, is a defunct satellite radio network that in its heyday provided service to over 170,000 subscribers in eastern, southern and northern Africa, the Middle East, and much of Asia with 96% coming from India. It was profitable in India, with 450,000 subscribers.
The two operational satellites that the company had, AfriStar and AsiaStar, are now being used by their new owner, the Yazmi USA, LLC run by WorldSpace's former CEO Noah A. Samara. The company claims to have built the first satellite-to-tablet content delivery system. The system primarily aims at providing educational services to rural areas in developing countries. The first pilots of the technology are said to be taking place in India (with 30,000 licenses) and the sub-Saharan region in Africa, with the latest trials in two schools in South Africa, in Rietkol, in Mpumalanga Province, and at Heathfield, in Western Cape.
Overview
The company, founded in 1990, has its headquarters in Silver Spring, Maryland and additional studios were located in Washington, D.C., Bangalore, Mumbai, New Delhi, and Nairobi. In 1991 Noah Samara, working with Thomas van der Heyden – founder of what was then International Telecommunications Inc. (ITI), later in 1997 to become the geostationary satellite division of Orbital Sciences, prepared and filed for the world's first Radio Broadcast Satellite with the US FCC. In 1992, Samara and van der Heyden (at the time representing the Republic of Indonesia) were able, at WARC-92 with the support of many African and Asian countries, to have the ITU establish a new radio frequency spectrum band dedicated to Broadcast Satellite Services (BSS) in the L-band – 1,452 MHz – 1,492 MHz. After WARC-92 Samara went on to build WorldSpace and van der Heyden to build IndoVison and the Indostar S-band Direct Broadcast Satellite satellite program for Indonesia.
WorldSpace first began broadcasting satellite radio on 1 October 1999, in Africa. In a last-ditch but ultimately completely unsuccessful effort to avoid commercial insolvency in July 2008, WorldSpace changed its brand and corporate identity to 1worldspace.
Before filing for bankruptcy in October 2008, 1worldspace employed two satellites and broadcast 62 channels – 38 of which were content provided by international, national and regional third parties and 24 1worldspace-branded stations produced by or for 1worldspace. Most of the channels used to be available only through a subscription plan.
1worldspace claimed to be the only company with rights to the world's globally allocated spectrum for digital satellite radio. However, it never made use of its license to broadcast to the Americas or the Caribbean. The company gained attention around 2000 because of its willingness to invest in impoverished areas and from 2006 to the present due to its financial difficulties and bankruptcy proceedings.
European operations were liquidated in the spring of 2009. On Dece |
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