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πŸ”— Athletics at the 1904 Summer Olympics: Men's Marathon

πŸ”— Olympics πŸ”— Athletics

The men's marathon at the 1904 Summer Olympics in St. Louis, United States, took place on August 30 of that year, over a distance of 24.85Β miles (40Β km).

The race was run during the hottest part of the day on dusty country roads with minimal water supply; while thirty-two athletes representing four nations competed, only 14 managed to complete the race, which was a bizarre affair due to poor organization and officiating. While Fred Lorz was greeted as the apparent winner, he was later disqualified as he had hitched a ride in a car for part of the race. The actual winner, Thomas Hicks, was near collapse and hallucinating by the end of the race, a side effect of being administered brandy, raw eggs, and strychnine by his trainers. The fourth-place finisher, AndarΓ­n Carvajal, took a nap during the race after eating spoiled apples.

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πŸ”— McCollough effect

πŸ”— Psychology

The McCollough effect is a phenomenon of human visual perception in which colorless gratings appear colored contingent on the orientation of the gratings. It is an aftereffect requiring a period of induction to produce it. For example, if someone alternately looks at a red horizontal grating and a green vertical grating for a few minutes, a black-and-white horizontal grating will then look greenish and a black-and-white vertical grating will then look pinkish. The effect is remarkable because, where time-elapse testing is employed, it has been reported to last up to 2.8 months.

The effect was discovered by American psychologist Celeste McCollough in 1965.

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πŸ”— Pattern theory

πŸ”— Mathematics

Pattern theory, formulated by Ulf Grenander, is a mathematical formalism to describe knowledge of the world as patterns. It differs from other approaches to artificial intelligence in that it does not begin by prescribing algorithms and machinery to recognize and classify patterns; rather, it prescribes a vocabulary to articulate and recast the pattern concepts in precise language. Broad in its mathematical coverage, Pattern Theory spans algebra and statistics, as well as local topological and global entropic properties.

In addition to the new algebraic vocabulary, its statistical approach is novel in its aim to:

  • Identify the hidden variables of a data set using real world data rather than artificial stimuli, which was previously commonplace.
  • Formulate prior distributions for hidden variables and models for the observed variables that form the vertices of a Gibbs-like graph.
  • Study the randomness and variability of these graphs.
  • Create the basic classes of stochastic models applied by listing the deformations of the patterns.
  • Synthesize (sample) from the models, not just analyze signals with them.

The Brown University Pattern Theory Group was formed in 1972 by Ulf Grenander. Many mathematicians are currently working in this group, noteworthy among them being the Fields Medalist David Mumford. Mumford regards Grenander as his "guru" in Pattern Theory.

πŸ”— As We May Think

πŸ”— Computing πŸ”— Libraries

"As We May Think" is a 1945 essay by Vannevar Bush which has been described as visionary and influential, anticipating many aspects of information society. It was first published in The Atlantic in July 1945 and republished in an abridged version in September 1945β€”before and after the atomic bombings of Hiroshima and Nagasaki. Bush expresses his concern for the direction of scientific efforts toward destruction, rather than understanding, and explicates a desire for a sort of collective memory machine with his concept of the memex that would make knowledge more accessible, believing that it would help fix these problems. Through this machine, Bush hoped to transform an information explosion into a knowledge explosion.

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πŸ”— Shoelace formula

πŸ”— Mathematics

The shoelace formula or shoelace algorithm (also known as Gauss's area formula and the surveyor's formula) is a mathematical algorithm to determine the area of a simple polygon whose vertices are described by their Cartesian coordinates in the plane. The user cross-multiplies corresponding coordinates to find the area encompassing the polygon, and subtracts it from the surrounding polygon to find the area of the polygon within. It is called the shoelace formula because of the constant cross-multiplying for the coordinates making up the polygon, like tying shoelaces. It is also sometimes called the shoelace method. It has applications in surveying and forestry, among other areas.

The formula was described by Meister (1724–1788) in 1769 and by Gauss in 1795. It can be verified by dividing the polygon into triangles, and can be considered to be a special case of Green's theorem.

The area formula is derived by taking each edge AB, and calculating the area of triangle ABO with a vertex at the origin O, by taking the cross-product (which gives the area of a parallelogram) and dividing by 2. As one wraps around the polygon, these triangles with positive and negative area will overlap, and the areas between the origin and the polygon will be cancelled out and sum to 0, while only the area inside the reference triangle remains. This is why the formula is called the surveyor's formula, since the "surveyor" is at the origin; if going counterclockwise, positive area is added when going from left to right and negative area is added when going from right to left, from the perspective of the origin.

The area formula can also be applied to self-overlapping polygons since the meaning of area is still clear even though self-overlapping polygons are not generally simple. Furthermore, a self-overlapping polygon can have multiple "interpretations" but the Shoelace formula can be used to show that the polygon's area is the same regardless of the interpretation.

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πŸ”— Pigeon photography

πŸ”— Military history πŸ”— Military history/Military science, technology, and theory πŸ”— Military history/World War I πŸ”— Military history/German military history πŸ”— Birds πŸ”— Photography πŸ”— Photography/History of photography πŸ”— Military history/European military history

Pigeon photography is an aerial photography technique invented in 1907 by the German apothecary Julius Neubronner, who also used pigeons to deliver medications. A homing pigeon was fitted with an aluminium breast harness to which a lightweight time-delayed miniature camera could be attached. Neubronner's German patent application was initially rejected, but was granted in December 1908 after he produced authenticated photographs taken by his pigeons. He publicized the technique at the 1909 Dresden International Photographic Exhibition, and sold some images as postcards at the Frankfurt International Aviation Exhibition and at the 1910 and 1911 Paris Air Shows.

Initially, the military potential of pigeon photography for aerial reconnaissance appeared interesting. Battlefield tests in World War I provided encouraging results, but the ancillary technology of mobile dovecotes for messenger pigeons had the greatest impact. Owing to the rapid perfection of aviation during the war, military interest in pigeon photography faded and Neubronner abandoned his experiments. The idea was briefly resurrected in the 1930s by a Swiss clockmaker, and reportedly also by the German and French militaries. Although war pigeons were deployed extensively during World War II, it is unclear to what extent, if any, birds were involved in aerial reconnaissance. The United States Central Intelligence Agency (CIA) later developed a battery-powered camera designed for espionage pigeon photography; details of its use remain classified.

The construction of sufficiently small and light cameras with a timer mechanism, and the training and handling of the birds to carry the necessary loads, presented major challenges, as did the limited control over the pigeons' position, orientation and speed when the photographs were being taken. In 2004, the British Broadcasting Corporation (BBC) used miniature television cameras attached to falcons and goshawks to obtain live footage, and today some researchers, enthusiasts and artists similarly deploy crittercams with various species of animals.

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πŸ”— Hoover (Seal)

πŸ”— United States πŸ”— Biography πŸ”— United States/Massachusetts πŸ”— Mammals πŸ”— Zoo

Hoover (c. 1971 – July 25, 1985) was a harbor seal who was able to imitate basic human speech.

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πŸ”— Alan Smithee

πŸ”— Film πŸ”— Film/American cinema πŸ”— Film/Filmmaking πŸ”— Fictional characters

Alan Smithee (also Allen Smithee) is an official pseudonym used by film directors who wish to disown a project. Coined in 1968 and used until it was formally discontinued in 2000, it was the sole pseudonym used by members of the Directors Guild of America (DGA) when a director, dissatisfied with the final product, proved to the satisfaction of a guild panel that they had not been able to exercise creative control over a film. The director was also required by guild rules not to discuss the circumstances leading to the movie or even to acknowledge being the project's director.

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πŸ”— The Cuckoo's Egg

πŸ”— Espionage πŸ”— Books πŸ”— Computer Security πŸ”— Computer Security/Computing

The Cuckoo's Egg: Tracking a Spy Through the Maze of Computer Espionage is a 1989 book written by Clifford Stoll. It is his first-person account of the hunt for a computer hacker who broke into a computer at the Lawrence Berkeley National Laboratory (LBNL).

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πŸ”— Wikipedia Has Cancer

Alternative Title: Just because you have some money, that doesn't mean that you have to spend it.

In biology, the hallmarks of an aggressive cancer include limitless multiplication of ordinarily beneficial cells, even when the body signals that further multiplication is no longer needed. The Wikipedia page on the wheat and chessboard problem explains that nothing can keep growing forever. In biology, the unwanted growth usually terminates with the death of the host. Ever-increasing spending can often lead to the same undesirable result in organizations.

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