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

The M65 atomic cannon, often called "Atomic Annie", was an artillery piece built by the United States and capable of firing a nuclear device. It was developed in the early 1950s, at the beginning of the Cold War, and fielded, between April 1955 and December 1962, in West Germany, South Korea and on Okinawa.

🔗 Computing 🔗 Computing/Software

CMS Pipelines implements the pipeline concept under the VM/CMS operating system. The programs in a pipeline operate on a sequential stream of records. A program writes records that are read by the next program in the pipeline. Any program can be combined with any other because reading and writing is done through a device independent interface.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Military history/Cold War

The W54 (also known as the Mark 54 or B54) was a tactical nuclear warhead developed by the United States in the late 1950s. The weapon is notable for being the smallest nuclear weapon in both weight and yield to have entered US service. It was a compact implosion device containing plutonium-239 as its fissile material, and in its various versions and mods it had a yield of 10 to 1,000 tons of TNT (42 to 4,184 gigajoules).

The weapon had two distinct versions: a warhead used in the AIM-26 Falcon air-to-air missile and in the Davy Crockett recoilless gun, and another used in the Special Atomic Demolition Munition (SADM) system, along with several mods for each version. The two types are distinct in that much of the design between them was different, to the point that during the development of the SADM it was proposed that it be given its own unique mark designation.

A later development was the W72, which was a rebuilt W54 used with the AGM-62 Walleye guided bomb. The W72 was in service until 1979.

🔗 Biography 🔗 Russia 🔗 Russia/mass media in Russia 🔗 Psychology 🔗 Russia/science and education in Russia

Solomon Veniaminovich Shereshevsky (Russian: Соломон Вениаминович Шерешевский; 1886 – 1 May 1958), also known simply as 'Ш' ('Sh'), 'S.', or Luria's S, was a Soviet journalist and mnemonist active in the 1920s. He was the subject of Alexander Luria's case study The Mind of a Mnemonist (1968).

🔗 Canada 🔗 Geology 🔗 Canada/Ontario 🔗 Canada/Manitoba 🔗 Canada/Geography of Canada 🔗 Lakes 🔗 Canada/Saskatchewan

Lake Agassiz was a very large glacial lake in central North America. Fed by glacial meltwater at the end of the last glacial period, its area was larger than all of the modern Great Lakes combined though its mean depth was not as great as that of many major lakes today.

First postulated in 1823 by William H. Keating, it was named by Warren Upham in 1879 after Louis Agassiz, when Upham recognized that the lake was formed by glacial action.

🔗 Chess 🔗 Japan

Taikyoku shōgi (Japanese: 大局将棋) lit. "ultimate chess" is the largest known variant of shogi (Japanese chess). The game was created around the mid-16th century (presumably by priests) and is based on earlier large board shogi games. Before the rediscovery of taikyoku shogi in 1997, tai shogi was believed to be the largest playable chess variant ever. It has not been shown that taikyoku shogi was ever widely played. There are only two sets of restored taikyoku shogi pieces and one of them is held at Osaka University of Commerce. One game may be played over several long sessions and require each player to make over a thousand moves.

Because the game was found only recently after centuries of obscurity, it is difficult to say exactly what all the rules were. Several documents describing the game have been found; however, there are differences between them. Many of the pieces appear in other shogi variants but their moves may be different. The board, and likewise the pieces, were made much smaller, making archeological finds difficult to decipher. Research into this game continues for historical and cultural reasons, but also to satisfy the curious and those who wish to play what could be the most challenging chess-like game ever made. More research must be done however. This article focuses on one likely set of rules that can make the game playable in modern times but is by no means canon. These rules may change as more discoveries are made and secrets of the game unlocked.

Further, because of the terse and often incomplete wording of the historical sources for the large shogi variants, except for chu shogi and to a lesser extent dai shogi (which were at some points of time the most prestigious forms of shogi being played), the historical rules of taikyoku shogi are not clear. Different sources often differ significantly in the moves attributed to the pieces, and the degree of contradiction (summarised below with the listing of most known alternative moves) is such that it is likely impossible to reconstruct the "true historical rules" with any degree of certainty, if there ever was such a thing. It is not clear if the game was ever played much historically, as there is no record of any sets having been made.

In computer science, the ski rental problem is a name given to a class of problems in which there is a choice between continuing to pay a repeating cost or paying a one-time cost which eliminates or reduces the repeating cost.

🔗 Korea 🔗 Physics 🔗 Chemicals 🔗 Electrical engineering 🔗 Materials

LK-99 is a proposed ambient pressure and room-temperature superconductor with a gray‒black appearance.^: 8 LK-99 has a hexagonal structure slightly modified from lead‒apatite and is claimed to function as a superconductor below 400 K (127 °C; 260 °F).^: 1 The material was investigated by a team of Sukbae Lee et al. from the Korea Institute of Science and Technology (KIST).^: 1 As of 26 July 2023 the discovery of LK-99 has not been peer reviewed or independently replicated.

The chemical composition of LK-99 is approximately Pb₉Cu(PO₄)₆O such that—compared to pure lead-apatite (Pb₁₀(PO₄)₆O)^: 5—approximately one quarter of Pb(2) ions are replaced by Cu(II) ions.^: 9 This partial replacement of Pb²⁺ ions (measuring 133 picometre) with Cu²⁺ ions (measuring 87 picometre) is said to cause a 0.48% reduction in volume, creating internal stress inside the material.^: 8

The internal stress is claimed to cause a heterojunction quantum well between the Pb(1) and oxygen within the phosphate ([PO₄]³⁻) generating a superconducting quantum well (SQW).^: 10 Lee et al claim to show LK-99 exhibits a response to a magnetic field (Meissner effect) when chemical vapor deposition is used to apply LK-99 to a non-magnetic copper sample.^: 4 Pure lead-apatite is an insulator, but Lee et al claim copper-doped lead-apatite forming LK-99 is a superconductor, or at higher temperatures, a metal.^: 5

🔗 Law

In contract law, a non-compete clause (often NCC), or covenant not to compete (CNC), is a clause under which one party (usually an employee) agrees not to enter into or start a similar profession or trade in competition against another party (usually the employer). Some courts refer to these as "restrictive covenants". As a contract provision, a CNC is bound by traditional contract requirements including the consideration doctrine.

The use of such clauses is premised on the possibility that upon their termination or resignation, an employee might begin working for a competitor or start a business, and gain competitive advantage by exploiting confidential information about their former employer's operations or trade secrets, or sensitive information such as customer/client lists, business practices, upcoming products, and marketing plans.

However, an over-broad CNC may prevent an employee from working elsewhere at all. English common law originally held any such constraint to be unenforceable under the public policy doctrine. Contemporary case law permits exceptions, but generally will only enforce CNCs to the extent necessary to protect the employer. Most jurisdictions in which such contracts have been examined by the courts have deemed CNCs to be legally binding so long as the clause contains reasonable limitations as to the geographical area and time period in which an employee of a company may not compete.

The extent to which non-compete clauses are legally allowed varies per jurisdiction. For example, the state of California in the United States invalidates non-compete-clauses for all but equity stakeholders in the sale of business interests.