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๐Ÿ”— Law of Demeter

๐Ÿ”— Computing

The Law of Demeter (LoD) or principle of least knowledge is a design guideline for developing software, particularly object-oriented programs. In its general form, the LoD is a specific case of loose coupling. The guideline was proposed by Ian Holland at Northeastern University towards the end of 1987, and can be succinctly summarized in each of the following ways:

  • Each unit should have only limited knowledge about other units: only units "closely" related to the current unit.
  • Each unit should only talk to its friends; don't talk to strangers.
  • Only talk to your immediate friends.

The fundamental notion is that a given object should assume as little as possible about the structure or properties of anything else (including its subcomponents), in accordance with the principle of "information hiding". It may be viewed as a corollary to the principle of least privilege, which dictates that a module possess only the information and resources necessary for its legitimate purpose.

It is so named for its origin in the Demeter Project, an adaptive programming and aspect-oriented programming effort. The project was named in honor of Demeter, โ€œdistribution-motherโ€ and the Greek goddess of agriculture, to signify a bottom-up philosophy of programming which is also embodied in the law itself.

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๐Ÿ”— Andreev Bay nuclear accident of 1982

๐Ÿ”— Soviet Union

The Andreev Bay nuclear accident took place at Soviet naval base 569 in February 1982. Andreev Bay is a radioactive waste repository, located 55ย km (34 mi) northwest of Murmansk and 60ย km (37 mi) from the Norwegian border on the western shore of the Zapadnaya Litsa (Kola Peninsula). The repository entered service in 1961. In February 1982, a nuclear accident occurred in which radioactive water was released from a pool in building #5. Cleanup of the accident took place from 1983 to 1989. About 700,000 tonnes (770,000 tons) of highly radioactive water leaked into the Barents Sea during that time period. About 1,000 people took part in the cleanup effort. Vladimir Konstantinovich Bulygin, who was in charge of the naval fleet's radiation accidents, received the Hero of the Soviet Union distinction for his work.

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๐Ÿ”— Downsโ€“Thomson paradox

๐Ÿ”— Economics ๐Ÿ”— Transport

The Downsโ€“Thomson paradox (named after Anthony Downs and John Michael Thomson), also known as the Pigouโ€“Knightโ€“Downs paradox (after Arthur Cecil Pigou and Frank Knight), states that the equilibrium speed of car traffic on a road network is determined by the average door-to-door speed of equivalent journeys taken by public transport.

It is a paradox in that improvements in the road network will not reduce traffic congestion. Improvements in the road network can make congestion worse if the improvements make public transport more inconvenient or if it shifts investment, causing disinvestment in the public transport system.

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๐Ÿ”— Guy Goma (2006)

๐Ÿ”— Biography ๐Ÿ”— Africa ๐Ÿ”— BBC ๐Ÿ”— Africa/Republic of the Congo

Guy Goma (born 1969) is a Congolese-French business studies graduate from Brazzaville in the Republic of the Congo who was accidentally interviewed live on BBC News 24, a UK television news station, on Monday 8 May 2006. Goma was mistaken for technology expert Guy Kewney when he attended the BBC for a job interview and was brought onto a BBC special regarding the case Apple Corps v Apple Computer to provide insight on a subject he knew little about.

Goma became well known for the incident, which is noted as a memorable TV moment.

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๐Ÿ”— Stigler Diet

The Stigler diet is an optimization problem named for George Stigler, a 1982 Nobel Laureate in economics, who posed the following problem:

For a moderately active man weighing 154 pounds, how much of each of 77 foods should be eaten on a daily basis so that the manโ€™s intake of nine nutrients will be at least equal to the recommended dietary allowances (RDAs) suggested by the National Research Council in 1943, with the cost of the diet being minimal?

The nutrient RDAs required to be met in Stiglerโ€™s experiment were calories, protein, calcium, iron, as well as vitamins A, B1, B2, B3, and C. The result was an annual budget allocated to foods such as evaporated milk, cabbage, dried navy beans, and beef liver at a cost of approximately $0.11 a day in 1939 U.S. dollars.

While the name โ€œStigler Dietโ€ was applied after the experiment by outsiders, according to Stigler, โ€œNo one recommends these diets for anyone, let alone everyone.โ€ The Stigler diet has been much ridiculed for its lack of variety and palatability; however, his methodology has received praise and is considered to be some of the earliest work in linear programming.

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๐Ÿ”— 2007 Boston Mooninite Panic

๐Ÿ”— United States ๐Ÿ”— Marketing & Advertising ๐Ÿ”— Guild of Copy Editors ๐Ÿ”— United States/Massachusetts - Boston ๐Ÿ”— United States/American television ๐Ÿ”— Cartoon Network

On the morning of January 31, 2007, the Boston Police Department and the Boston Fire Department mistakenly identified battery-powered LED placards depicting the Mooninites, characters from the Adult Swim animated television series Aqua Teen Hunger Force, as improvised explosive devices (IEDs), leading to a massive panic. Placed throughout Boston, Massachusetts, and the surrounding cities of Cambridge and Somerville by Peter "Zebbler" Berdovsky and Sean Stevens, these devices were part of a nationwide guerrilla marketing advertising campaign for Aqua Teen Hunger Force Colon Movie Film for Theaters.

The massive panic led to controversy and criticism from U.S. media sources, including The Boston Globe, Los Angeles Times, Fox News, The San Francisco Chronicle, The New York Times, CNN, and The Boston Herald. Some ridiculed the city's response to the devicesโ€”including the arrests of the two men hired to place the placards around the areaโ€”as disproportionate and indicative of a generation gap between city officials and the younger residents of Boston, at whom the ads were targeted. Several sources noted that the hundreds of officers in the Boston police department or city emergency planning office on scene were unable to identify the figure depicted for several hours until a young staffer at Mayor Thomas Menino's office saw the media coverage and recognized the figures.

After the devices were removed, the Boston Police Department stated in its defense that the ad devices shared some similarities with improvised explosive devices, with them also discovering an identifiable power source, a circuit board with exposed wiring, and electrical tape. Investigators were not mollified by the discovery that the devices were not explosive in nature, stating they still intended to determine "if this event was a hoax or something else entirely". Although city prosecutors eventually concluded there was no ill intent involved in the placing of the ads, the city continues to refer to the event as a "bomb hoax" (implying intent) rather than a "bomb scare".

Reflecting years later, various academics and media sources have characterized the phenomenon as a form of social panic. Gregory Bergman wrote in his 2008 book BizzWords that the devices were basically a self-made form of the children's toy Lite-Brite. Bruce Schneier wrote in his 2009 book Schneier on Security that Boston officials were "ridiculed" for their overreaction to the incident. In his 2009 book Secret Agents, historian and communication professor Jeremy Packer discussed a cultural phenomenon called the "panic discourse" and described the incident as a "spectacular instance of this panic". In a 2012 article, The Boston Phoenix called the incident the "Great Mooninite Panic of 2007". A 2013 publication by WGBH wrote that the majority of Boston youth thought that the arrests of two men who placed devices were not justified.

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๐Ÿ”— Darvaza Gas Crater

๐Ÿ”— Central Asia ๐Ÿ”— Mining ๐Ÿ”— Central Asia/Turkmenistan ๐Ÿ”— Turkmenistan

The Darvaza gas crater (Turkmen: Garagum รฝalkymy), also known as the Door to Hell or Gates of Hell, or, officially, the Shining of Karakum, is a burning natural gas field collapsed into a cavern near Darvaza, Turkmenistan. The floor and especially rim of the crater is illumined by hundreds of natural gas fires. The crater has been burning for an unknown amount of time, as how the crater formed and ignited remains unknown.

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๐Ÿ”— Wireless USB

๐Ÿ”— Computing ๐Ÿ”— Computing/Networking

Wireless USB was a short-range, high-bandwidth wireless radio communication protocol created by the Wireless USB Promoter Group which intended to increase the availability of general USB-based technologies. It is unrelated to Wi-Fi. It was maintained by the WiMedia Alliance which ceased operations in 2009. Wireless USB is sometimes abbreviated as "WUSB", although the USB Implementers Forum discouraged this practice and instead prefers to call the technology Certified Wireless USB to distinguish it from the competing UWB standard.

Wireless USB was based on the (now defunct) WiMedia Alliance's Ultra-WideBand (UWB) common radio platform, which is capable of sending 480ย Mbit/s at distances up to 3 metres (9.8ย ft) and 110ย Mbit/s at up to 10 metres (33ย ft). It was designed to operate in the 3.1 to 10.6ย GHz frequency range, although local regulatory policies may restrict the legal operating range in some countries.

The standard is now obsolete, and no new hardware has been produced for many years.

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๐Ÿ”— St Scholastica Day Riot (1355)

๐Ÿ”— Crime ๐Ÿ”— Law ๐Ÿ”— England ๐Ÿ”— Middle Ages ๐Ÿ”— Middle Ages/History ๐Ÿ”— Law Enforcement ๐Ÿ”— Sociology ๐Ÿ”— University of Oxford ๐Ÿ”— British crime

The St Scholastica Day riot took place in Oxford, England, on 10 February 1355, Saint Scholastica's Day. The disturbance began when two students from the University of Oxford complained about the quality of wine served to them in the Swindlestock Tavern, which stood on Carfax, in the centre of the town. The students quarrelled with the taverner; the argument quickly escalated to blows. The inn's customers joined in on both sides, and the resulting melee turned into a riot. The violence started by the bar brawl continued over three days, with armed gangs coming in from the countryside to assist the townspeople. University halls and students' accommodation were raided and the inhabitants murdered; there were some reports of clerics being scalped. Around 30 townsfolk were killed, as were up to 63 members of the university.

Violent disagreements between townspeople and students had arisen several times previously, and 12 of the 29 coroners' courts held in Oxford between 1297 and 1322 concerned murders by students. The University of Cambridge was established in 1209 by scholars who left Oxford following the lynching of two students by the town's citizens.

King Edward III sent judges to the town with commissions of oyer and terminer to determine what had gone on and to advise what steps should be taken. He came down on the side of the university authorities, who were given additional powers and responsibilities to the disadvantage of the town's authorities. The town was fined 500 marks and its mayor and bailiffs were sent to the Marshalsea prison in London. John Gynwell, the Bishop of Lincoln, imposed an interdict on the town for one year, which banned all religious practices, including services (except on key feast days), burials and marriages; only baptisms of young children were allowed.

An annual penance was imposed on the town: each year, on St Scholastica's Day, the mayor, bailiffs and sixty townspeople were to attend a Mass at the University Church of St Mary the Virgin for those killed; the town was also made to pay the university a fine of one penny for each scholar killed. The practice was dropped in 1825; in 1955โ€”the 600th anniversary of the riotsโ€”in an act of conciliation the mayor was given an honorary degree and the vice-chancellor was made an honorary freeman of the city.

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