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🔗 Nuffield Science Project

🔗 United Kingdom 🔗 Education 🔗 Science

The Nuffield Science Teaching Project was a programme to develop a better approach to teaching science in British secondary schools, under the auspices of the Nuffield Foundation. Although not intended as a curriculum, it gave rise to alternative national examinations, and its use of discovery learning was influential in the 1960s and 1970s.

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🔗 Bitching Betty

🔗 Aviation

Bitching Betty is a slang term used by some pilots and aircrew (mainly North American), when referring to the voices used by some aircraft warning systems.

The enunciating voice, in at least some aircraft systems, may be either male or female and in some cases this may be selected according to pilot preference. If the voice is female, it may be referred to as Bitching Betty; if the voice is male, it may be referred to as Barking Bob. A female voice is heard on military aircraft such as the F-16 Fighting Falcon, the Eurofighter Typhoon and the Mikoyan MiG-29. A male voice is heard on Boeing commercial airliners and is also used in the BAE Hawk.

In the United Kingdom the term Nagging Nora is sometimes used, and in New Zealand the term used for Boeing aircraft is Hank the Yank. The voice warning system used on London Underground trains, which also uses a female voice, is known to some staff as Sonya, as it "gets on ya nerves".

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🔗 Wolpertinger

🔗 Germany 🔗 Folklore

In German folklore, a wolpertinger (also called wolperdinger or woiperdinger) is an animal said to inhabit the alpine forests of Bavaria and Baden-Württemberg in Germany.

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🔗 Chrestomathy

🔗 Literature

A chrestomathy ( kreh-STOM-ə-thee; from the Ancient Greek χρηστομάθεια khrēstomátheia 'desire of learning', from χρηστός khrēstós 'useful' + μανθάνω manthánō 'learn') is a collection of selected literary passages (usually from a single author); a selection of literary passages from a foreign language assembled for studying the language; or a text in various languages, used especially as an aid in learning a subject.

In philology or in the study of literature, it is a type of reader which presents a sequence of example texts, selected to demonstrate the development of language or literary style. It is different from an anthology because of its didactic purpose.

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🔗 Goro Shimura has died

🔗 Biography 🔗 Biography/science and academia

Gorō Shimura (志村 五郎, Shimura Gorō, 23 February 1930 – 3 May 2019) was a Japanese mathematician and Michael Henry Strater Professor Emeritus of Mathematics at Princeton University who worked in number theory, automorphic forms, and arithmetic geometry. He was known for developing the theory of complex multiplication of abelian varieties and Shimura varieties, as well as posing the Taniyama–Shimura conjecture which ultimately led to the proof of Fermat's Last Theorem.

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🔗 Gödel Machine

🔗 Computing

A Gödel machine is a hypothetical self-improving computer program that solves problems in an optimal way. It uses a recursive self-improvement protocol in which it rewrites its own code when it can prove the new code provides a better strategy. The machine was invented by Jürgen Schmidhuber (first proposed in 2003), but is named after Kurt Gödel who inspired the mathematical theories.

The Gödel machine is often discussed when dealing with issues of meta-learning, also known as "learning to learn." Applications include automating human design decisions and transfer of knowledge between multiple related tasks, and may lead to design of more robust and general learning architectures. Though theoretically possible, no full implementation has been created.

The Gödel machine is often compared with Marcus Hutter's AIXItl, another formal specification for an artificial general intelligence. Schmidhuber points out that the Gödel machine could start out by implementing AIXItl as its initial sub-program, and self-modify after it finds proof that another algorithm for its search code will be better.

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🔗 Blue Field Entoptic Phenomenon

🔗 Medicine 🔗 Biology

The blue field entoptic phenomenon is an entoptic phenomenon characterized by the appearance of tiny bright dots (nicknamed blue-sky sprites) moving quickly along undulating pathways in the visual field, especially when looking into bright blue light such as the sky. The dots are short-lived, visible for about one second or less, and traveling short distances along seemingly random, undulating paths. Some of them seem to follow the same path as other dots before them. The dots may appear elongated along the path, like tiny worms. The dots' rate of travel appears to vary in synchrony with the heartbeat: they briefly accelerate at each beat. The dots appear in the central field of view, within 15 degrees from the fixation point. The left and right eye see different, seemingly random, dot patterns; a person viewing through both eyes sees a combination of both left and right visual field disturbances. While seeing the phenomenon, lightly pressing inward on the sides of the eyeballs at the lateral canthus causes the movement to stop being fluid and the dots to move only when the heart beats.

Most people are able to see this phenomenon in the sky, although it is relatively weak in most instances; many will not notice it until asked to pay attention. The dots are highly conspicuous against any monochromatic blue background of a wavelength of around 430 nm in place of the sky. The phenomenon is also known as Scheerer's phenomenon, after the German ophthalmologist Richard Scheerer, who first drew clinical attention to it in 1924.

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🔗 Ulam Spiral

🔗 Mathematics

The Ulam spiral or prime spiral is a graphical depiction of the set of prime numbers, devised by mathematician Stanisław Ulam in 1963 and popularized in Martin Gardner's Mathematical Games column in Scientific American a short time later. It is constructed by writing the positive integers in a square spiral and specially marking the prime numbers.

Ulam and Gardner emphasized the striking appearance in the spiral of prominent diagonal, horizontal, and vertical lines containing large numbers of primes. Both Ulam and Gardner noted that the existence of such prominent lines is not unexpected, as lines in the spiral correspond to quadratic polynomials, and certain such polynomials, such as Euler's prime-generating polynomial x2 − x + 41, are believed to produce a high density of prime numbers. Nevertheless, the Ulam spiral is connected with major unsolved problems in number theory such as Landau's problems. In particular, no quadratic polynomial has ever been proved to generate infinitely many primes, much less to have a high asymptotic density of them, although there is a well-supported conjecture as to what that asymptotic density should be.

In 1932, more than thirty years prior to Ulam's discovery, the herpetologist Laurence Klauber constructed a triangular, non-spiral array containing vertical and diagonal lines exhibiting a similar concentration of prime numbers. Like Ulam, Klauber noted the connection with prime-generating polynomials, such as Euler's.

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🔗 Phoebus Cartel

🔗 Technology 🔗 Business 🔗 Electronics 🔗 Energy 🔗 Home Living

The Phoebus cartel existed to control the manufacture and sale of incandescent light bulbs. They appropriated market territories and fixed the useful life of such bulbs. Corporations based in Europe and America founded the cartel on January 15, 1925 in Geneva. They had intended the cartel to last for thirty years (1925 to 1955). The cartel ceased operations in 1939 owing to the outbreak of World War II. The cartel included manufacturers Osram, General Electric, Associated Electrical Industries, and Philips, among others.

The Phoebus cartel created a notable landmark in the history of the global economy because it engaged in large-scale planned obsolescence to generate repeated sales and maximize profit. It also reduced competition in the light bulb industry for almost fifteen years. Critics accused the cartel of preventing technological advances that would produce longer-lasting light bulbs. Phoebus based itself in Switzerland. The corporation named itself Phœbus S.A. Compagnie Industrielle pour le Développement de l'Éclairage (French for "Phoebus, Inc. Industrial Company for the Development of Lighting").

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🔗 Bus Factor

🔗 Computing 🔗 Business 🔗 Computing/Software

The bus factor is a measurement of the risk resulting from information and capabilities not being shared among team members, derived from the phrase "in case they get hit by a bus." It is also known as the bread truck scenario, lottery factor, truck factor, bus/truck number, or lorry factor.

The concept is similar to the much older idea of key person risk, but considers the consequences of losing key technical experts, versus financial or managerial executives (who are theoretically replaceable at an insurable cost). Personnel must be both key and irreplaceable to contribute to the bus factor; losing a replaceable or non-key person would not result in a bus-factor effect.

The term was first applied to software development, where a team member might create critical components by crafting code that performs well, but which also is unavailable to other team members, such as work that was undocumented, never shared, encrypted, obfuscated, unpublished, or otherwise incomprehensible to others. Thus a key component would be effectively lost as a direct consequence of the absence of that team member, making the member key. If this component was key to the project's advancement, the project would stall.

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