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🔗 Commons-based peer production

🔗 Economics 🔗 Sociology

Commons-based peer production (CBPP) is a term coined by Harvard Law School professor Yochai Benkler. It describes a model of socio-economic production in which large numbers of people work cooperatively; usually over the Internet. Commons-based projects generally have less rigid hierarchical structures than those under more traditional business models. Often—but not always—commons-based projects are designed without a need for financial compensation for contributors. For example, sharing of STL (file format) design files for objects freely on the internet enables anyone with a 3-D printer to digitally replicate the object saving the prosumer significant money.

The term is often used interchangeably with the term social production.

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🔗 Lowest temperature recorded on Earth

🔗 Physics 🔗 Antarctica

The lowest natural temperature ever directly recorded at ground level on Earth is −89.2 °C (−128.6 °F; 184.0 K) at the Soviet Vostok Station in Antarctica on 21 July 1983 by ground measurements.

On 10 August 2010, satellite observations showed a surface temperature of −93.2 °C (−135.8 °F; 180.0 K) at 81.8°S 59.3°E / -81.8; 59.3, along a ridge between Dome Argus and Dome Fuji, at 3,900 m (12,800 ft) elevation. The result was reported at the 46th annual meeting of the American Geophysical Union in San Francisco in December 2013; it is a provisional figure, and may be subject to revision. The value is not listed as the record lowest temperature as it was measured by remote sensing from satellite and not by ground-based thermometers, unlike the 1983 record. The temperature announced reflects that of the ice surface, while the Vostok readings measured the air above the ice, and so the two are not directly comparable. More recent work shows many locations in the high Antarctic where surface temperatures drop to approximately −98 °C (−144 °F; 175 K). Due to the very strong temperature gradient near the surface, these imply near-surface air temperature minima of approximately −94 °C (−137 °F; 179 K).

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🔗 Peter Naur has died

🔗 Biography 🔗 Computer science 🔗 Biography/science and academia 🔗 Denmark

Peter Naur (25 October 1928 – 3 January 2016) was a Danish computer science pioneer and Turing award winner. His last name is the "N" in the BNF notation (Backus–Naur form), used in the description of the syntax for most programming languages. He contributed to the creation of the ALGOL 60 programming language.

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🔗 Band-e Kaisar – “Caesar's dam”‎‎

🔗 Iran 🔗 Classical Greece and Rome 🔗 Dams 🔗 Bridges and Tunnels

The Band-e Kaisar (Persian: بند قیصر, "Caesar's dam"‎), Pol-e Kaisar ("Caesar's bridge"), Bridge of Valerian or Shadirwan was an ancient arch bridge in Shushtar, Iran, and the first in the country to combine it with a dam. Built by the Sassanids, using Roman prisoners of war as workforce, in the 3rd century AD on Sassanid order, it was also the most eastern example of Roman bridge design and Roman dam, lying deep in Persian territory. Its dual-purpose design exerted a profound influence on Iranian civil engineering and was instrumental in developing Sassanid water management techniques.

The approximately 500 m long overflow dam over the Karun, Iran's most effluent river, was the core structure of the Shushtar Historical Hydraulic System (سازه‌های آبی شوشتر) from which the city derived its agricultural productivity, and which has been designated by the UNESCO as Iran's 10th World Heritage Site in 2009. The arched superstructure carried across the important road between Pasargadae and the Sassanid capital Ctesiphon. Many times repaired in the Islamic period, the dam bridge remained in use until the late 19th century.

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🔗 NAR 2: Serbian Assembly Language

NAR 2 (Serbian Nastavni Računar 2, en. Educational Computer 2) is a theoretical model of a 32-bit word computer created by Faculty of Mathematics of University of Belgrade professor Nedeljko Parezanović as an enhancement to its predecessor, NAR 1. It was used for Assembly language and Computer architecture courses. The word "nar" means Pomegranate in Serbian. Many NAR 2 simulators have been created — for instance, one was named "Šljiva" (en. plum) as that fruit grows in Serbia, while "nar" does not.

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🔗 Tennis for Two was an electronic game developed in 1958 on an analog computer

🔗 Video games 🔗 Tennis

Tennis for Two (also known as Computer Tennis) is a sports video game, which simulates a game of tennis, and was one of the first games developed in the early history of video games. American physicist William Higinbotham designed the game in 1958 for display at the Brookhaven National Laboratory's annual public exhibition after learning that the government research institution's Donner Model 30 analog computer could simulate trajectories with wind resistance. He designed the game, displayed on an oscilloscope and played with two custom aluminum controllers, in a few hours, after which he and technician Robert V. Dvorak built it over three weeks. The game's visuals show a representation of a tennis court viewed from the side, and players adjust the angle of their shots with a knob on their controller and try to hit the ball over the net by pressing a button.

The game was very popular during the three-day exhibition, with players lining up to see the game, especially high school students. It was shown again the following year with a larger oscilloscope screen and a more complicated design that could simulate different gravity levels. It was then dismantled and largely forgotten until the late 1970s when Higinbotham testified in court about the game during lawsuits between Magnavox and Ralph H. Baer over video game patents. Since then, it has been celebrated as one of the earliest video games, and Brookhaven has made recreations of the original device. Under some definitions Tennis for Two is considered the first video game, as while it did not include any technological innovations over prior games, it was the first computer game to be created purely as an entertainment product rather than for academic research or commercial technology promotion.

🔗 Lumpers and Splitters

🔗 Science 🔗 Tree of Life

Lumpers and splitters are opposing factions in any discipline that has to place individual examples into rigorously defined categories. The lumper–splitter problem occurs when there is the desire to create classifications and assign examples to them, for example schools of literature, biological taxa and so on. A "lumper" is an individual who takes a gestalt view of a definition, and assigns examples broadly, assuming that differences are not as important as signature similarities. A "splitter" is an individual who takes precise definitions, and creates new categories to classify samples that differ in key ways.

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🔗 The Anamorphic Skull in Holbein's “The Ambassadors”

🔗 London 🔗 Visual arts

The Ambassadors (1533) is a painting by Hans Holbein the Younger. Also known as Jean de Dinteville and Georges de Selve, it was created in the Tudor period, in the same year Elizabeth I was born. As well as being a double portrait, the painting contains a still life of several meticulously rendered objects, the meaning of which is the cause of much debate. It also incorporates a much-cited example of anamorphosis in painting. It is part of the collection at the National Gallery in London.

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🔗 SNAP-10A was an experimental nuclear reactor launched into space in 1965

🔗 Spaceflight

SNAP-10A (Systems for Nuclear, Auxiliary Power, aka Snapshot for Space Nuclear Auxiliary Power Shot, also known as OPS 4682, COSPAR 1965-027A) was a US experimental nuclear powered satellite launched into space in 1965 as part of the SNAPSHOT program. The test marked the world's first operation of a nuclear reactor in orbit, and also the first operation of an ion thruster system in orbit. It is the only fission reactor power system launched into space by the United States. The reactor stopped working after just 43 days due to a non-nuclear electrical component failure. The Systems Nuclear Auxiliary Power Program (SNAP) reactor was specifically developed for satellite use in the 1950s and early 1960s under the supervision of the U.S. Atomic Energy Commission.

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🔗 Music Macro Language

🔗 Video games 🔗 Computing 🔗 Electronic music

Music Macro Language (MML) is a music description language used in sequencing music on computer and video game systems.