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πŸ”— Athens Charter

πŸ”— Architecture πŸ”— Greece πŸ”— Urban studies and planning πŸ”— Greece/Athens

The Athens Charter (French: Charte d'AthΓ¨nes, Greek: Χάρτα των Ξ‘ΞΈΞ·Ξ½ΟŽΞ½) was a 1933 document about urban planning published by the Swiss architect Le Corbusier. The work was based upon Le Corbusier’s Ville Radieuse (Radiant City) book of 1935 and urban studies undertaken by the CongrΓ¨s International d'Architecture Moderne (CIAM) in the early 1930s.

The Charter got its name from location of the fourth CIAM conference in 1933, which, due to the deteriorating political situation in Russia, took place on the S.S. Patris bound for Athens from Marseille. This conference is documented in a film commissioned by Sigfried Giedion and made by his friend Laszlo Moholy-Nagy: "Architects' Congress."

The Charter had a significant impact on urban planning after World War II.

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πŸ”— RIP Mike Karels 1956-2024

πŸ”— United States πŸ”— Biography πŸ”— Biography/science and academia

Michael J. (Mike) Karels (August 2, 1956 – June 2, 2024) was an American software engineer and one of the key figures in history of BSD UNIX.

In 1993, the USENIX Association gave a Lifetime Achievement Award (Flame) to the Computer Systems Research Group at University of California, Berkeley, honoring 180 individuals, including Karels, who contributed to the CSRG's 4.4BSD-Lite release.

In February 1992 Karels moved to BSDi (Berkeley Software Design) and designed BSD/OS, which, for years, was the only commercially available BSD style Unix on Intel platform. BSDi's software assets were bought by Wind River in April 2001, and Karels joined Wind River as the Principal Technologist for the BSD/OS platform.

Following his time at Wind River, Karels joined Secure Computing Corporation in 2003 as a Sr. Principal Engineer. Secure Computing used BSD/OS as the basis for SecureOS, the operating system of its Sidewinder firewall, later known as McAfee Firewall Enterprise. However, BSD/OS development had ceased, so Karels was involved in transitioning SecureOS to use FreeBSD as its base, and porting its unique features over to the new kernel. Secure Computing and the Sidewinder firewall team went through a series of acquisitions and spinoffs, including McAfee, Intel, and Forcepoint, so while Karels appeared to have several different jobs from that point onward, he had remained in roughly the same role from 2003 until his retirement in 2021.

The Sidewinder product was eventually discontinued, though Karels fed some SecureOS changes back into the main FreeBSD codebase. Karels officially became a FreeBSD committer in 2017. He continued working on FreeBSD in his spare time following retirement.

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πŸ”— XOR Linked List

πŸ”— Ships

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πŸ”— Hearing the Shape of a Drum

πŸ”— Mathematics πŸ”— Percussion

To hear the shape of a drum is to infer information about the shape of the drumhead from the sound it makes, i.e., from the list of overtones, via the use of mathematical theory.

"Can One Hear the Shape of a Drum?" is the title of a 1966 article by Mark Kac in the American Mathematical Monthly which made the question famous, though this particular phrasing originates with Lipman Bers. Similar questions can be traced back all the way to Hermann Weyl . For his paper, Kac was given the Lester R. Ford Award in 1967 and the Chauvenet Prize in 1968.

The frequencies at which a drumhead can vibrate depend on its shape. The Helmholtz equation calculates the frequencies if the shape is known. These frequencies are the eigenvalues of the Laplacian in the space. A central question is whether the shape can be predicted if the frequencies are known; for example, whether a circle-shaped triangle can be recognized in this way. Kac admitted he did not know if it was possible for two different shapes to yield the same set of frequencies. The question of whether the frequencies determine the shape was finally answered in the negative in the early 1990s by Gordon, Webb and Wolpert.

πŸ”— Pentium floating-point division bug (1994)

πŸ”— Computing πŸ”— Computing/Computer hardware

The Pentium FDIV bug is a hardware bug affecting the floating-point unit (FPU) of the early Intel Pentium processors. Because of the bug, the processor would return incorrect binary floating point results when dividing certain pairs of high-precision numbers. The bug was discovered in 1994 by Thomas R. Nicely, a professor of mathematics at Lynchburg College. Missing values in a lookup table used by the FPU's floating-point division algorithm led to calculations acquiring small errors. While these errors would in most use-cases only occur rarely and result in small deviations from the correct output values, in certain circumstances the errors can occur frequently and lead to more significant deviations.

The severity of the FDIV bug is debated. Though rarely encountered by most users (Byte magazine estimated that 1 in 9 billion floating point divides with random parameters would produce inaccurate results), both the flaw and Intel's initial handling of the matter were heavily criticized by the tech community.

In December 1994, Intel recalled the defective processors in what was the first full recall of a computer chip. In its 1994 annual report, Intel said it incurred "a $475 million pre-tax chargeΒ ... to recover replacement and write-off of these microprocessors."

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πŸ”— Ellison's Cave

πŸ”— Georgia (U.S. state) πŸ”— Caves

Ellison's Cave is a pit cave located in Walker County, on Pigeon Mountain in the Appalachian Plateaus of Northwest Georgia. It is the 12th deepest cave in the United States and features the deepest, unobstructed pit in the continental US named Fantastic Pit. The cave is over 12 miles long and extends 1063 feet vertically.

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πŸ”— Microtome

πŸ”— Biology πŸ”— Neuroscience πŸ”— Physiology πŸ”— Science

A microtome (from the Greek mikros, meaning "small", and temnein, meaning "to cut") is a cutting tool used to produce extremely thin slices of material known as sections, with the process being termed microsectioning. Important in science, microtomes are used in microscopy for the preparation of samples for observation under transmitted light or electron radiation.

Microtomes use steel, glass or diamond blades depending upon the specimen being sliced and the desired thickness of the sections being cut. Steel blades are used to prepare histological sections of animal or plant tissues for light microscopy. Glass knives are used to slice sections for light microscopy and to slice very thin sections for electron microscopy. Industrial grade diamond knives are used to slice hard materials such as bone, teeth and tough plant matter for both light microscopy and for electron microscopy. Gem-quality diamond knives are also used for slicing thin sections for electron microscopy.

Microtomy is a method for the preparation of thin sections for materials such as bones, minerals and teeth, and an alternative to electropolishing and ion milling. Microtome sections can be made thin enough to section a human hair across its breadth, with section thickness between 50Β nm and 100Β ΞΌm.

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πŸ”— Embrace, Extend, and Extinguish

πŸ”— Computing πŸ”— Marketing & Advertising πŸ”— Computing/Software πŸ”— Computing/Free and open-source software πŸ”— Open πŸ”— Microsoft

"Embrace, extend, and extinguish" (EEE), also known as "embrace, extend, and exterminate", is a phrase that the U.S. Department of Justice found was used internally by Microsoft to describe its strategy for entering product categories involving widely used standards, extending those standards with proprietary capabilities, and then using those differences in order to strongly disadvantage its competitors.

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πŸ”— USS Pueblo

πŸ”— United States πŸ”— Military history πŸ”— Military history/North American military history πŸ”— Military history/United States military history πŸ”— Korea πŸ”— Military history/Maritime warfare πŸ”— Ships πŸ”— Pritzker Military Library πŸ”— Korea/North Korea πŸ”— United States/Colorado

USS Pueblo (AGER-2) is a Banner-class environmental research ship, attached to Navy intelligence as a spy ship, which was attacked and captured by North Korean forces on 23 January 1968, in what is known today as the "Pueblo incident" or alternatively, as the "Pueblo crisis".

The seizure of the U.S. Navy ship and her 83 crew members, one of whom was killed in the attack, came less than a week after President Lyndon B. Johnson's State of the Union address to the United States Congress, a week before the start of the Tet Offensive in South Vietnam during the Vietnam War and three days after 31 men of North Korea's KPA Unit 124 had crossed the Korean Demilitarized Zone (DMZ) and killed 26 South Koreans in an attempt to attack the South Korean Blue House (executive mansion) in the capital Seoul. The taking of Pueblo and the abuse and torture of her crew during the subsequent 11-month prisoner drama became a major Cold War incident, raising tensions between western and eastern powers.

North Korea stated that Pueblo deliberately entered their territorial waters 7.6 nautical miles (14Β km) away from Ryo Island, and that the logbook shows that they intruded several times. However, the United States maintains that the vessel was in international waters at the time of the incident and that any purported evidence supplied by North Korea to support its statements was fabricated. Pueblo, still held by North Korea today, officially remains a commissioned vessel of the United States Navy. Since early 2013, the ship has been moored along the Pothong River in Pyongyang and used there as a museum ship at the Victorious War Museum. Pueblo is the only ship of the U.S. Navy still on the commissioned roster currently being held captive.

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πŸ”— Cluny: The Google of 1000

πŸ”— France πŸ”— Architecture πŸ”— Middle Ages πŸ”— Middle Ages/History πŸ”— Catholicism

Cluny Abbey (French:Β [klyni]; formerly also Cluni, or Clugny) is a former Benedictine monastery in Cluny, SaΓ΄ne-et-Loire, France. It was dedicated to St Peter.

The abbey was constructed in the Romanesque architectural style, with three churches built in succession from the 4th to the early 12th centuries. The earliest basilica was the world's largest church until the St. Peter's Basilica construction began in Rome.

Cluny was founded by Duke William I of Aquitaine in 910. He nominated Berno as the first abbot of Cluny, subject only to Pope Sergius III. The abbey was notable for its stricter adherence to the Rule of St. Benedict, whereby Cluny became acknowledged as the leader of western monasticism. The establishment of the Benedictine Order was a keystone to the stability of European society that was achieved in the 11th century. In 1790 during the French Revolution, the abbey was sacked and mostly destroyed, with only a small part surviving.

Starting around 1334, the Abbots of Cluny maintained a townhouse in Paris known as the HΓ΄tel de Cluny, which has been a public museum since 1843. Apart from the name, it no longer possesses anything originally connected with Cluny.

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