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🔗 Computing 🔗 Computing/Software 🔗 Computing/Networking

The fallacies of distributed computing are a set of assertions made by L Peter Deutsch and others at Sun Microsystems describing false assumptions that programmers new to distributed applications invariably make.

🔗 Technology 🔗 Underwater diving

Standard diving dress, also known as hard-hat or copper hat equipment, deep sea diving suit, or heavy gear, is a type of diving suit that was formerly used for all relatively deep underwater work that required more than breath-hold duration, which included marine salvage, civil engineering, pearl shell diving and other commercial diving work, and similar naval diving applications. Standard diving dress has largely been superseded by lighter and more comfortable equipment.

Standard diving dress consists of a diving helmet made from copper and brass or bronze, clamped over a watertight gasket to a waterproofed canvas suit, an air hose from a surface-supplied manually operated pump or low pressure breathing air compressor, a diving knife, and weights to counteract buoyancy, generally on the chest, back, and shoes. Later models were equipped with a diver's telephone for voice communications with the surface. The term deep sea diving was used to distinguish diving with this equipment from shallow water diving using a shallow water helmet, which was not sealed to the suit.

Some variants used rebreather systems to extend the use of gas supplies carried by the diver, and were effectively self-contained underwater breathing apparatus, and others were suitable for use with helium based breathing gases for deeper work. Divers could be deployed directly by lowering or raising them using the lifeline, or could be transported on a diving stage. Most diving work using standard dress was done heavy, with the diver sufficiently negatively buoyant to walk on the bottom, and the suits were not capable of the fine buoyancy control needed for mid-water swimming.

🔗 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 ${\displaystyle {^{n}a}}$ means ${\displaystyle {a^{a^{\cdot ^{\cdot ^{a}}}}}}$, where n copies of a are iterated via exponentiation, right-to-left, I.e. the application of exponentiation ${\displaystyle n-1}$ 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

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

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.

🔗 History of Science

A knowledge production mode is a term from the sociology of science which refers to the way (scientific) knowledge is produced. So far, three modes have been conceptualized. Mode 1 production of knowledge is knowledge production motivated by scientific knowledge alone (basic research) which is not primarily concerned by the applicability of its findings. Mode 1 is founded on a conceptualization of science as separated into discrete disciplines (e.g., a biologist does not bother about chemistry). Mode 2 was coined in 1994 in juxtaposition to Mode 1 by Michael Gibbons, Camille Limoges, Helga Nowotny, Simon Schwartzman, Peter Scott and Martin Trow. In Mode 2, multidisciplinary teams are brought together for short periods of time to work on specific problems in the real world for knowledge production (applied research) in the knowledge society. Mode 2 can be explained by the way research funds are distributed among scientists and how scientists focus on obtaining these funds in terms of five basic features: 1) knowledge produced in the context of application; (2) transdisciplinarity; (3) heterogeneity and organizational diversity; (4) social accountability and reflexivity; (5) and quality control. Subsequently, Carayannis and Campbell described a Mode 3 knowledge in 2006.

🔗 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.

🔗 France 🔗 Energy

The Odeillo solar furnace is the world's largest solar furnace. It is situated in Font-Romeu-Odeillo-Via, in the department of Pyrénées-Orientales, in south of France. It is 54 metres (177 ft) high and 48 metres (157 ft) wide, and includes 63 heliostats. It was built between 1962 and 1968, and started operating in 1969, and has a power of one megawatt.

It serves as a science research site studying materials at very high temperatures.

🔗 United States 🔗 United States/Arizona 🔗 Chicago 🔗 Mining 🔗 Organized Labour 🔗 United States/U.S. history 🔗 Latino and Hispanic heritage 🔗 Latino and Hispanic heritage/Mexican-American

The Bisbee Deportation was the illegal kidnapping and deportation of about 1,300 striking mine workers, their supporters, and citizen bystanders by 2,000 members of a deputized posse, who arrested them beginning on July 12, 1917, in Bisbee, Arizona. The action was orchestrated by Phelps Dodge, the major mining company in the area, which provided lists of workers and others who were to be arrested to the Cochise County sheriff, Harry C. Wheeler. Those arrested were taken to a local baseball park before being loaded onto cattle cars and deported 200 miles (320 km) to Tres Hermanas in New Mexico. The 16-hour journey was through desert without food and with little water. Once unloaded, the deportees, most without money or transportation, were warned against returning to Bisbee. The US government soon brought in members of the US Army to assist with relocating the deportees to Columbus, New Mexico.

As Phelps Dodge, in collusion with the sheriff, had closed down access to outside communications, it was some time before the story was reported. The company presented their action as reducing threats to United States interests in World War I in Europe, largely because the wartime demand for copper was heavy. The Governor of New Mexico, in consultation with President Woodrow Wilson, provided temporary housing for the deportees. A presidential mediation commission investigated the actions in November 1917, and in its final report, described the deportation as "wholly illegal and without authority in law, either State or Federal (Page 6)." Nevertheless, no individual, company, or agency was ever convicted in connection with the deportations. Arizona and Cochise County never prosecuted the case, and in United States v. Wheeler (1920), the Supreme Court ruled that the Constitution by itself does not give the federal government the power to stop kidnappings, even ones involving moving abductees across state lines on federally-regulated railroads.

🔗 Statistics

Extreme value theory or extreme value analysis (EVA) is a branch of statistics dealing with the extreme deviations from the median of probability distributions. It seeks to assess, from a given ordered sample of a given random variable, the probability of events that are more extreme than any previously observed. Extreme value analysis is widely used in many disciplines, such as structural engineering, finance, earth sciences, traffic prediction, and geological engineering. For example, EVA might be used in the field of hydrology to estimate the probability of an unusually large flooding event, such as the 100-year flood. Similarly, for the design of a breakwater, a coastal engineer would seek to estimate the 50-year wave and design the structure accordingly.

🔗 Architecture 🔗 Kent 🔗 Architecture/Historic houses 🔗 Historic sites

The Shell Grotto, sometimes called the Shell Temple, is an ornate underground shell grotto in the seaside town of Margate, Kent, England. The grotto, which has a passageway and main room, was dug out from chalk, a soft limestone common in the region. Almost all the surface area of the walls and roof is covered in mosaics created entirely of seashells, totalling about 2,000 square feet (190 m²) of mosaic, with approximately 4.6 million shells. Its age, creators, and purpose are unknown, which has inspired a wide range of speculation, although several other shell grottos in England were made in the 18th century. This grotto was rediscovered in about 1835 and first opened to the public as a privately-owned tourist attraction in 1837. The grotto is a Grade I-listed building and remains open to the public. Attached to the grotto is a modern museum room, cafe, and gift shop.

🔗 Death 🔗 Agriculture 🔗 China 🔗 Skepticism 🔗 Alternative medicine 🔗 Arab world 🔗 Agriculture/Beekeeping

A mellified man, or a human mummy confection, was a legendary medicinal substance created by steeping a human cadaver in honey. The concoction is detailed in Chinese medical sources, most significantly the Bencao Gangmu of the 16th-century Chinese medical doctor and pharmacologist Li Shizhen. Relying on a second-hand account, Li reports a story that some elderly men in Arabia, nearing the end of their lives, would submit themselves to a process of mummification in honey to create a healing confection.

This process differed from a simple body donation because of the aspect of self-sacrifice; the mellification process would ideally start before death. The donor would stop eating any food other than honey, going as far as to bathe in the substance. Shortly, his feces (and even his sweat, according to legend) would consist of honey. When this diet finally proved fatal, the donor's body would be placed in a stone coffin filled with honey.

After a century or so, the contents would have turned into a sort of confection reputedly capable of healing broken limbs and other ailments. This confection would then be sold in street markets as a hard to find item with a hefty price.