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🔗 Confused Deputy Problem

🔗 Computing 🔗 Computer Security 🔗 Computer Security/Computing 🔗 Computing/Software

In information security, a confused deputy is a computer program that is tricked by another program (with fewer privileges or less rights) into misusing its authority on the system. It is a specific type of privilege escalation. The confused deputy problem is often cited as an example of why capability-based security is important.

Capability systems protect against the confused deputy problem, whereas access-control list–based systems do not.

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🔗 Xinjiang Re-Education Camps

🔗 Human rights 🔗 China 🔗 Islam 🔗 Correction and Detention Facilities

The Xinjiang re-education camps, officially called Vocational Education and Training Centers by the government of the People's Republic of China, are internment camps that have been operated by the Xinjiang Uygur Autonomous Region government for the purpose of indoctrinating Uyghurs since 2017 as part of a "people's war on terror" announced in 2014. The camps were established under General Secretary Xi Jinping's administration and led by party secretary, Chen Quanguo. These camps are reportedly operated outside the legal system; many Uyghurs have reportedly been interned without trial and no charges have been levied against them. Local authorities are reportedly holding hundreds of thousands of Uyghurs in these camps as well as other ethnic minority groups, for the stated purpose of countering extremism and terrorism and promoting sinicization.

As of 2018, it was estimated that the Chinese authorities may have detained hundreds of thousands, perhaps a million, Uyghurs, Kazakhs, Kyrgyz and other ethnic Turkic Muslims, Christians as well as some foreign citizens such as Kazakhstanis, who are being held in these secretive internment camps which are located throughout the region. In May 2018, Randall Schriver of the United States Department of Defense claimed that "at least a million but likely closer to three million citizens" were imprisoned in detention centers in a strong condemnation of the "concentration camps". In August 2018, a United Nations human rights panel said that it had received many credible reports that 1 million ethnic Uyghurs in China have been held in "re-education camps". There have also been multiple reports from media, politicians and researchers comparing the camps to the Chinese Cultural Revolution.

In 2019, the United Nations ambassadors from 22 nations, including Australia, Canada, France, Germany, Japan, and the United Kingdom signed a letter condemning China's mass detention of the Uyghurs and other minority groups, urging the Chinese government to close the camps. Conversely, a joint statement was signed by 37 states commending China's counter-terrorism program in Xinjiang, including Algeria, the DR Congo, Russia, Saudi Arabia, Syria, Iran, Iraq, Pakistan, North Korea, Egypt, Nigeria, the Philippines and Sudan.

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🔗 Wet-Bulb Temperature

🔗 Physics 🔗 Weather 🔗 Weather/Meteorological instruments and data

The wet-bulb temperature (WBT) is the temperature read by a thermometer covered in water-soaked cloth (a wet-bulb thermometer) over which air is passed. At 100% relative humidity, the wet-bulb temperature is equal to the air temperature (dry-bulb temperature); at lower humidity the wet-bulb temperature is lower than dry-bulb temperature because of evaporative cooling.

The wet-bulb temperature is defined as the temperature of a parcel of air cooled to saturation (100% relative humidity) by the evaporation of water into it, with the latent heat supplied by the parcel. A wet-bulb thermometer indicates a temperature close to the true (thermodynamic) wet-bulb temperature. The wet-bulb temperature is the lowest temperature that can be reached under current ambient conditions by the evaporation of water only.

Even heat-adapted people cannot carry out normal outdoor activities past a wet-bulb temperature of 32 °C (90 °F), equivalent to a heat index of 55 °C (130 °F). The theoretical limit to human survival for more than a few hours in the shade, even with unlimited water, is a wet-bulb temperature of 35 °C (95 °F) – theoretically equivalent to a heat index of 70 °C (160 °F), though the heat index does not go that high.

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🔗 Wireworld

🔗 Computing 🔗 Mathematics

Wireworld is a cellular automaton first proposed by Brian Silverman in 1987, as part of his program Phantom Fish Tank. It subsequently became more widely known as a result of an article in the "Computer Recreations" column of Scientific American. Wireworld is particularly suited to simulating transistors, and Wireworld is Turing-complete.

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🔗 Boom XB-1 Baby Boom

🔗 Aviation 🔗 Aviation/aircraft

The Boom XB-1 Baby Boom is a one-third-scale supersonic demonstrator designed by Boom Technology, designed as part of development of the Boom Overture supersonic transport airliner. It is planned to maintain Mach 2.2, with over 1,000 nmi (1,900 km) of range. Powered by three 4,300 lbf (19 kN) dry General Electric CJ610s, it is expected to be flight tested in 2020.

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🔗 Hachikō

🔗 Dogs 🔗 Japan 🔗 Public Art 🔗 Japan/History

Hachikō (ハチ公, November 10, 1923 – March 8, 1935) was a Japanese Akita dog remembered for his remarkable loyalty to his owner, Hidesaburō Ueno, for whom he continued to wait for over nine years following Ueno's death.

Hachikō was born on November 10, 1923, at a farm near the city of Ōdate, Akita Prefecture. In 1924, Hidesaburō Ueno, a professor at the Tokyo Imperial University, brought him to live in Shibuya, Tokyo, as his pet. Hachikō would meet Ueno at Shibuya Station every day after his commute home. This continued until May 21, 1925, when Ueno died of a cerebral hemorrhage while at work. From then until his death on March 8, 1935, Hachikō would return to Shibuya Station every day to await Ueno's return.

During his lifetime, the dog was held up in Japanese culture as an example of loyalty and fidelity. Well after his death, he continues to be remembered in worldwide popular culture, with statues, movies, books, and appearances in various media. Hachikō is known in Japanese as chūken Hachikō (忠犬ハチ公) "faithful dog Hachikō", hachi meaning "eight" and the suffix -kō indicating affection.

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🔗 FOGBANK

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Physics 🔗 Chemistry

FOGBANK is a code name given to a material used in nuclear weapons such as the W76, W78 and W80.

FOGBANK's precise nature is classified; in the words of former Oak Ridge general manager Dennis Ruddy, "The material is classified. Its composition is classified. Its use in the weapon is classified, and the process itself is classified." Department of Energy Nuclear Explosive Safety documents simply describe it as a material "used in nuclear weapons and nuclear explosives" along with lithium hydride (LiH) and lithium deuteride (LiD), beryllium (Be), uranium hydride (UH3), and plutonium hydride.

However National Nuclear Security Administration (NNSA) Administrator Tom D'Agostino disclosed the role of FOGBANK in the weapon: "There's another material in the—it's called interstage material, also known as fog bank", and arms experts believe that FOGBANK is an aerogel material which acts as an interstage material in a nuclear warhead; i.e., a material designed to become a superheated plasma following the detonation of the weapon's fission stage, the plasma then triggering the fusion-stage detonation.

🔗 Celtuce

🔗 China 🔗 Food and drink 🔗 Plants 🔗 Taiwan 🔗 Project-independent assessment

Celtuce () (Lactuca sativa var. augustana, angustata, or asparagina), also called stem lettuce, celery lettuce, asparagus lettuce, or Chinese lettuce, is a cultivar of lettuce grown primarily for its thick stem or its leaves, which are known as A-choy. It is used as a vegetable. In China, the family is informally called woju (traditional Chinese: 萵苣; simplified Chinese: 莴苣; pinyin: wōjù), which is also the name of a cultivar. It is especially popular in both China and Taiwan, where the stem is interchangeably called wosun (traditional Chinese: 萵筍; simplified Chinese: 莴笋; pinyin: wōsǔn) or qingsun(青筍; 青笋; qīngsǔn).

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🔗 Tetration

🔗 Mathematics

In mathematics, tetration (or hyper-4) is an operation based on iterated, or repeated, exponentiation. It is the next hyperoperation after exponentiation, but before pentation. The word was coined by Reuben Louis Goodstein from tetra- (four) and iteration.

Under the definition as repeated exponentiation, the notation n a {\displaystyle {^{n}a}} means a a a {\displaystyle {a^{a^{\cdot ^{\cdot ^{a}}}}}} , where n copies of a are iterated via exponentiation, right-to-left, I.e. the application of exponentiation n 1 {\displaystyle n-1} times. n is called the "height" of the function, while a is called the "base," analogous to exponentiation. It would be read as "the nth tetration of a".

Tetration is also defined recursively as

n a := { 1 if  n = 0 a ( ( n 1 ) a ) if  n > 0 {\displaystyle {^{n}a}:={\begin{cases}1&{\text{if }}n=0\\a^{\left(^{(n-1)}a\right)}&{\text{if }}n>0\end{cases}}} ,

allowing for attempts to extend tetration to non-natural numbers such as real and complex numbers.

The two inverses of tetration are called the super-root and the super-logarithm, analogous to the nth root and the logarithmic functions. None of the three functions are elementary.

Tetration is used for the notation of very large numbers.

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🔗 Cippi of Melqart

🔗 History 🔗 Ancient Near East 🔗 Malta 🔗 Phoenicia

The Cippi of Melqart are a pair of Phoenician marble cippi that were unearthed in Malta under undocumented circumstances and dated to the 2nd century BC. These are votive offerings to the god Melqart, and are inscribed in two languages, Ancient Greek and Phoenician, and in the two corresponding scripts, the Greek and the Phoenician alphabet. They were discovered in the late 17th century, and the identification of their inscription in a letter dated 1694 made them the first Phoenician writing to be identified and published in modern times. Because they present essentially the same text (with some minor differences), the cippi provided the key to the modern understanding of the Phoenician language. In 1758, the French scholar Jean-Jacques Barthélémy relied on their inscription, which used 17 of the 22 letters of the Phoenician alphabet, to decipher the unknown language.

The tradition that the cippi were found in Marsaxlokk was only inferred by their dedication to Heracles, whose temple in Malta had long been identified with the remains at Tas-Silġ. The Grand Master of the Order of the Knights Hospitaller, Fra Emmanuel de Rohan-Polduc, presented one of the cippi to the Académie des Inscriptions et Belles-Lettres in 1782. This cippus is currently in the Louvre Museum in Paris, while the other rests in the National Museum of Archaeology in Valletta, Malta. The inscription is known as KAI 47.