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πŸ”— L-System

πŸ”— Computer science πŸ”— Mathematics πŸ”— Systems

An L-system or Lindenmayer system is a parallel rewriting system and a type of formal grammar. An L-system consists of an alphabet of symbols that can be used to make strings, a collection of production rules that expand each symbol into some larger string of symbols, an initial "axiom" string from which to begin construction, and a mechanism for translating the generated strings into geometric structures. L-systems were introduced and developed in 1968 by Aristid Lindenmayer, a Hungarian theoretical biologist and botanist at the University of Utrecht. Lindenmayer used L-systems to describe the behaviour of plant cells and to model the growth processes of plant development. L-systems have also been used to model the morphology of a variety of organisms and can be used to generate self-similar fractals.

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πŸ”— Transparent Aluminum

πŸ”— Chemicals

Aluminium oxynitride (marketed under the name ALON by Surmet Corporation) is a transparent ceramic composed of aluminium, oxygen and nitrogen. ALON is optically transparent (β‰₯Β 80%) in the near-ultraviolet, visible, and midwave-infrared regions of the electromagnetic spectrum. It is four times as hard as fused silica glass, 85% as hard as sapphire, and nearly 115% as hard as magnesium aluminate spinel. Since it has a cubic spinel structure, it can be fabricated to transparent windows, plates, domes, rods, tubes, and other forms using conventional ceramic powder processing techniques.

ALON is the hardest polycrystalline transparent ceramic available commercially. Because of its relatively low weight, distinctive optical and mechanical properties, and resistance to oxidation or radiation, it shows promise for applications such as bulletproof, blast-resistant, and optoelectronic windows. ALON-based armor has been shown to stop multiple armor-piercing projectiles of up to .50 BMG.

ALON is commercially available in sizes as large as 18-by-35-inch (460Β mm Γ—Β 890Β mm; 46Β cm Γ—Β 89Β cm) monolithic windows.

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πŸ”— Worker-Priest

πŸ”— Europe/ESA

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πŸ”— Comparison of parser generators

πŸ”— Computing πŸ”— Computer science πŸ”— Computing/Software

This is a list of notable lexer generators and parser generators for various language classes.

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πŸ”— Timeline of audio formats

πŸ”— Professional sound production

An audio format is a medium for sound recording and reproduction. The term is applied to both the physical recording media and the recording formats of the audio contentβ€”in computer science it is often limited to the audio file format, but its wider use usually refers to the physical method used to store the data.

Music is recorded and distributed using a variety of audio formats, some of which store additional information.

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πŸ”— What do Bill Gates and Richard Stallman have in common ?

πŸ”— United States πŸ”— Mathematics πŸ”— Education πŸ”— United States/Massachusetts πŸ”— Higher Education

Math 55 is a two-semester long first-year undergraduate mathematics course at Harvard University, founded by Lynn Loomis and Shlomo Sternberg. The official titles of the course are Honors Abstract Algebra (Math 55a) and Honors Real and Complex Analysis (Math 55b). Previously, the official title was Honors Advanced Calculus and Linear Algebra.

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πŸ”— Wireworld

πŸ”— Computing πŸ”— 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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πŸ”— Western Oil: the US/UK-Backed Iranian Coup D'Γ©tat of 1953

πŸ”— United States/U.S. Government πŸ”— United States πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Iran πŸ”— Military history/Intelligence πŸ”— Military history/Middle Eastern military history πŸ”— Project-independent assessment

The 1953 Iranian coup d'Γ©tat, known in Iran as the 28 Mordad coup d'Γ©tat (Persian: کودΨͺای Ϋ²ΫΈ Ω…Ψ±Ψ―Ψ§Ψ―), was the overthrow of Prime Minister Mohammad Mosaddegh on 19 August 1953. Led by the Iranian army and supported by the United States and the United Kingdom, the coup aimed at strengthening the autocratic rule of the shah Mohammad Reza Pahlavi. A key motive was to protect British oil interests in Iran after its government refused to concede to western oil demands. It was instigated by the United States (under the name TP-AJAX Project or Operation Ajax) and the United Kingdom (under the name Operation Boot). This began a period of dissolution for Iranian democracy and society.

Mosaddegh had sought to audit the documents of the Anglo-Iranian Oil Company (AIOC), a British corporation (now part of BP), to verify that AIOC was paying the contracted royalties to Iran, and to limit the company's control over Iranian oil reserves. Upon the AIOC's refusal to cooperate with the Iranian government, the parliament (Majlis) voted to nationalize Iran's oil industry and to expel foreign corporate representatives from the country. After this vote, Britain instigated a worldwide boycott of Iranian oil to pressure Iran economically. Initially, Britain mobilized its military to seize control of the British-built Abadan oil refinery, then the world's largest, but Prime Minister Clement Attlee (in power until 1951) opted instead to tighten the economic boycott while using Iranian agents to undermine Mosaddegh's government.:β€Š3β€Š Judging Mosaddegh to be unamenable and fearing the growing influence of the communist Tudeh, UK prime minister Winston Churchill and the Eisenhower administration decided in early 1953 to overthrow Iran's government. The preceding Truman administration had opposed a coup, fearing the precedent that Central Intelligence Agency (CIA) involvement would set,:β€Š3β€Š and the U.S. government had been considering unilateral action (without UK support) to assist the Mosaddegh government as late as 1952. British intelligence officials' conclusions and the UK government's solicitations to the US were instrumental in initiating and planning the coup.

Following the coup, a government under General Fazlollah Zahedi was formed which allowed Mohammad Reza Pahlavi, the shah of Iran (Persian for 'king'), to rule more firmly as monarch. He relied heavily on United States support to hold on to power. According to the CIA's declassified documents and records, some of the most feared mobsters in Tehran were hired by the CIA to stage pro-shah riots on 19 August. Other men paid by the CIA were brought into Tehran in buses and trucks and took over the streets of the city. Between 200 and 300 people were killed because of the conflict. Mosaddegh was arrested, tried and convicted of treason by the Shah's military court. On 21 December 1953, he was sentenced to three years in jail, then placed under house arrest for the remainder of his life.:β€Š280β€Š Other Mosaddegh supporters were imprisoned, and several received the death penalty. The coup strengthened the Shah's authority, and he continued to rule Iran for the next 26 years as a pro-Western monarch until he was overthrown in the Iranian Revolution in 1979.

In August 2013, the U.S. government formally acknowledged the U.S. role in the coup by releasing a bulk of previously classified government documents that show it was in charge of both the planning and the execution of the coup. According to American journalist Stephen Kinzer, the operation included false flag attacks, paid protesters, provocations, the bribing of Iranian politicians and high-ranking security and army officials, as well as pro-coup propaganda. The CIA is quoted as acknowledging the coup was carried out "under CIA direction" and "as an act of U.S. foreign policy, conceived and approved at the highest levels of government". In 2023, the CIA took credit for the coup, contradicting a previous scholarly assessment that the CIA had botched the operation, though other assessments agreed that America and Britain had engineered the coup.

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πŸ”— Nicole Oresme

πŸ”— Biography πŸ”— Mathematics πŸ”— Philosophy πŸ”— Philosophy/Social and political philosophy πŸ”— Biography/science and academia πŸ”— History of Science πŸ”— Middle Ages πŸ”— Middle Ages/History πŸ”— Philosophy/Philosophers πŸ”— Philosophy/Medieval philosophy

Nicole Oresme (French: [nikΙ”l ɔʁɛm]; c. 1320–1325 – 11 July 1382), also known as Nicolas Oresme, Nicholas Oresme, or Nicolas d'Oresme, was a French philosopher of the later Middle Ages. He wrote influential works on economics, mathematics, physics, astrology, astronomy, philosophy, and theology; was Bishop of Lisieux, a translator, a counselor of King Charles V of France, and one of the most original thinkers of 14th-century Europe.

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