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๐Ÿ”— Wet-Bulb Temperature

๐Ÿ”— Physics ๐Ÿ”— Weather ๐Ÿ”— 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 32ย ยฐC (90ย ยฐF), equivalent to a heat index of 55ย ยฐC (130ย ยฐF). 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 35ย ยฐC (95ย ยฐF) โ€“ theoretically equivalent to a heat index of 70ย ยฐC (160ย ยฐF), though the heat index does not go that high.

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๐Ÿ”— RFC-1149: IP over Avian Carriers

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

In computer networking, IP over Avian Carriers (IPoAC) is a proposal to carry Internet Protocol (IP) traffic by birds such as homing pigeons. IP over Avian Carriers was initially described in RFC 1149, a Request for Comments (RFC) issued by the Internet Engineering Task Force (IETF), written by D. Waitzman, and released on April 1, 1990. It is one of several April Fools' Day Request for Comments.

Waitzman described an improvement of his protocol in RFC 2549, IP over Avian Carriers with Quality of Service (1 April 1999). Later, in RFC 6214โ€”released on 1 April 2011, and 13 years after the introduction of IPv6โ€”Brian Carpenter and Robert Hinden published Adaptation of RFC 1149 for IPv6.

IPoAC has been successfully implemented, but for only nine packets of data, with a packet loss ratio of 55% (due to operator error), and a response time ranging from 3,000 seconds (โ‰ˆ54 minutes) to over 6,000 seconds (โ‰ˆ1.77 hours). Thus, this technology suffers from poor latency. Nevertheless, for large transfers, avian carriers are capable of high average throughput when carrying flash memory devices, effectively implementing a sneakernet. During the last 20 years, the information density of storage media and thus the bandwidth of an avian carrier has increased 3 times as fast as the bandwidth of the Internet. IPoAC may achieve bandwidth peaks of orders of magnitude more than the Internet when used with multiple avian carriers in rural areas. For example: If 16 homing pigeons are given eight 512ย GB SD cards each, and take an hour to reach their destination, the throughput of the transfer would be 145.6 Gbit/s, excluding transfer to and from the SD cards.

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๐Ÿ”— Secessio plebis

๐Ÿ”— Rome

Secessio plebis (withdrawal of the commoners, or secession of the plebs) was an informal exercise of power by Rome's plebeian citizens, similar in concept to the general strike. During the secessio plebis, the plebs would abandon the city en masse and leave the patrician order to themselves. Therefore, a secessio meant that all shops and workshops would shut down and commercial transactions would largely cease. This was an effective strategy in the Conflict of the Orders due to strength in numbers; plebeian citizens made up the vast majority of Rome's populace and produced most of its food and resources, while a patrician citizen was a member of the minority upper class, the equivalent of the landed gentry of later times. Authors report different numbers for how many secessions there were. Cary & Scullard state there were five between 494 BC and 287 BC.

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๐Ÿ”— Mรผnchhausen Trilemma

๐Ÿ”— Philosophy ๐Ÿ”— Philosophy/Logic ๐Ÿ”— Philosophy/Epistemology

In epistemology, the Mรผnchhausen trilemma is a thought experiment used to demonstrate the impossibility of proving any truth, even in the fields of logic and mathematics. If it is asked how any given proposition is known to be true, proof may be provided. Yet that same question can be asked of the proof, and any subsequent proof. The Mรผnchhausen trilemma is that there are only three options when providing further proof in response to further questioning:

  • The circular argument, in which the proof of some proposition is supported only by that proposition
  • The regressive argument, in which each proof requires a further proof, ad infinitum
  • The axiomatic argument, which rests on accepted precepts which are merely asserted rather than defended

The trilemma, then, is the decision among the three equally unsatisfying options.

The name Mรผnchhausen-Trilemma was coined by the German philosopher Hans Albert in 1968 in reference to a trilemma of "dogmatism versus infinite regress versus psychologism" used by Karl Popper. It is a reference to the problem of "bootstrapping", based on the story of Baron Munchausen (in German, "Mรผnchhausen") pulling himself and the horse on which he was sitting out of a mire by his own hair.

It is also known as Agrippa's trilemma or the Agrippan trilemma after a similar argument reported by Sextus Empiricus, which was attributed to Agrippa the Skeptic by Diogenes Laรซrtius, as well as Fries's trilemma after German philosopher Jakob Friedrich Fries. Sextus' argument, however, consists of five (not three) "modes". Popper in his original 1935 publication mentions neither Sextus nor Agrippa, but attributes his trilemma to Fries.

In contemporary epistemology, advocates of coherentism are supposed to accept the "circular" horn of the trilemma; foundationalists rely on the axiomatic argument. The view that accepts infinite regress is called infinitism.

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๐Ÿ”— Gruen transfer

๐Ÿ”— Architecture ๐Ÿ”— Marketing & Advertising ๐Ÿ”— Retailing ๐Ÿ”— Shopping Centers

In shopping mall design, the Gruen transfer (also known as the Gruen effect) is the moment when consumers enter a shopping mall or store and, surrounded by an intentionally confusing layout, lose track of their original intentions, making consumers more susceptible to make impulse buys. It is named for Austrian architect Victor Gruen, who disavowed such manipulative techniques.

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๐Ÿ”— Nine-nine-six (996) Working Hour System

๐Ÿ”— Companies ๐Ÿ”— China ๐Ÿ”— Organized Labour

The 996 working hour system (Chinese: 996ๅทฅไฝœๅˆถ) is a work schedule commonly practiced by some companies in the People's Republic of China. It derives its name from its requirement that employees work from 9:00 am to 9:00 pm, 6 days per week; i.e. 72 hours per week. A number of Chinese internet companies have adopted this system as their official work schedule. Critics argue that the 996 working hour system is a flagrant violation of Chinese law.

In March 2019 an "anti-996" protest was launched via GitHub.

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๐Ÿ”— Zenzizenzizenzic

๐Ÿ”— Mathematics ๐Ÿ”— Etymology

Zenzizenzizenzic is an obsolete form of mathematical notation representing the eighth power of a number (that is, the zenzizenzizenzic of x is x8), dating from a time when powers were written out in words rather than as superscript numbers. This term was suggested by Robert Recorde, a 16th-century Welsh writer of popular mathematics textbooks, in his 1557 work The Whetstone of Witte (although his spelling was zenzizenzizenzike); he wrote that it "doeth represent the square of squares squaredly".

At the time Recorde proposed this notation, there was no easy way of denoting the powers of numbers other than squares and cubes. The root word for Recorde's notation is zenzic, which is a German spelling of the medieval Italian word censo, meaning "squared". Since the square of a square of a number is its fourth power, Recorde used the word zenzizenzic (spelled by him as zenzizenzike) to express it. Some of the terms had prior use in Latin "zenzicubicus", "zensizensicus" and "zensizenzum". Similarly, as the sixth power of a number is equal to the square of its cube, Recorde used the word zenzicubike to express it; a more modern spelling, zenzicube, is found in Samuel Jeake's Logisticelogia. Finally, the word zenzizenzizenzic denotes the square of the square of a number's square, which is its eighth power: in modern notation,

x 8 = ( ( x 2 ) 2 ) 2 . {\displaystyle x^{8}=\left(\left(x^{2}\right)^{2}\right)^{2}.}

Recorde proposed three mathematical terms by which any power (that is, index or exponent) greater than 1 could be expressed: zenzic, i.e. squared; cubic; and sursolid, i.e. raised to a prime number greater than three, the smallest of which is five. Sursolids were as follows: 5 was the first; 7, the second; 11, the third; 13, the fourth; etc.

Therefore, a number raised to the power of six would be zenzicubic, a number raised to the power of seven would be the second sursolid, hence bissursolid (not a multiple of two and three), a number raised to the twelfth power would be the "zenzizenzicubic" and a number raised to the power of ten would be the square of the (first) sursolid. The fourteenth power was the square of the second sursolid, and the twenty-second was the square of the third sursolid.

Curiously, Jeake's text appears to designate a written exponent of 0 as being equal to an "absolute number, as if it had no Mark", thus using the notation x0 to refer to x alone, while a written exponent of 1, in his text, denotes "the Root of any number", thus using the notation x1 to refer to what is now known to be x0.5.

The word, as well as the system, is obsolete except as a curiosity; the Oxford English Dictionary (OED) has only one citation for it. As well as being a mathematical oddity, it survives as a linguistic oddity: zenzizenzizenzic has more Zs than any other word in the OED.

Samuel Jeake the Younger gives zenzizenzizenzizenzike (the square of the square of the square of the square, or 16th power) in a table in A Compleat Body of Arithmetick:

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๐Ÿ”— COINTELPRO

๐Ÿ”— United States ๐Ÿ”— Human rights ๐Ÿ”— History ๐Ÿ”— Politics ๐Ÿ”— Politics/American politics ๐Ÿ”— African diaspora ๐Ÿ”— United States History ๐Ÿ”— United States/FBI ๐Ÿ”— Civil Rights Movement ๐Ÿ”— United States/U.S. history

COINTELPRO (syllabic abbreviation derived from COunter INTELligence PROgram) (1956โ€“1971) was a series of covert and, at times, illegal projects conducted by the United States Federal Bureau of Investigation (FBI) aimed at surveilling, infiltrating, discrediting, and disrupting American political organizations. FBI records show that COINTELPRO resources targeted groups and individuals that the FBI deemed subversive, including feminist organizations, the Communist Party USA, antiโ€“Vietnam War organizers, activists of the civil rights movement or Black Power movement (e.g. Martin Luther King Jr., the Nation of Islam, and the Black Panther Party), environmentalist and animal rights organizations, the American Indian Movement (AIM), independence movements (such as Puerto Rican independence groups like the Young Lords), and a variety of organizations that were part of the broader New Left. The program also targeted the Ku Klux Klan in 1964.

In another instance in San Diego, the FBI financed, armed, and controlled an extreme right-wing group of former members of the Minutemen anti-communist para-military organization, transforming it into a group called the Secret Army Organization that targeted groups, activists, and leaders involved in the Anti-War Movement, using both intimidation and violent acts.

The FBI has used covert operations against domestic political groups since its inception; however, covert operations under the official COINTELPRO label took place between 1956 and 1971. COINTELPRO tactics are still used to this day and have been alleged to include discrediting targets through psychological warfare; smearing individuals and groups using forged documents and by planting false reports in the media; harassment; wrongful imprisonment; and illegal violence, including assassination. The FBI's stated motivation was "protecting national security, preventing violence, and maintaining the existing social and political order".

Beginning in 1969, leaders of the Black Panther Party were targeted by the COINTELPRO and "neutralized" by being assassinated, imprisoned, publicly humiliated or falsely charged with crimes. Some of the Black Panthers affected included Fred Hampton, Mark Clark, Zayd Shakur, Geronimo Pratt, Mumia Abu-Jamal, and Marshall Conway. Common tactics used by COINTELPRO were perjury, witness harassment, witness intimidation, and withholding of evidence.

FBI Director J. Edgar Hoover issued directives governing COINTELPRO, ordering FBI agents to "expose, disrupt, misdirect, discredit, or otherwise neutralize" the activities of these movements and especially their leaders. Under Hoover, the agent in charge of COINTELPRO was William C. Sullivan. Attorney General Robert F. Kennedy personally authorized some of the programs. Although Kennedy only gave written approval for limited wiretapping of Martin Luther King's phones "on a trial basis, for a month or so", Hoover extended the clearance so his men were "unshackled" to look for evidence in any areas of King's life they deemed worthy.

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๐Ÿ”— Uranium Glass

๐Ÿ”— Glass

Uranium glass is glass which has had uranium, usually in oxide diuranate form, added to a glass mix before melting for coloration. The proportion usually varies from trace levels to about 2% uranium by weight, although some 20th-century pieces were made with up to 25% uranium.

Uranium glass was once made into tableware and household items, but fell out of widespread use when the availability of uranium to most industries was sharply curtailed during the Cold War in the 1940s to 1990s. Most such objects are now considered antiques or retro-era collectibles, although there has been a minor revival in art glassware. Otherwise, modern uranium glass is now mainly limited to small objects like beads or marbles as scientific or decorative novelties.

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