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🔗 France 🔗 Economics 🔗 Cooperatives 🔗 Basque 🔗 Spain

The Mondragon Corporation is a corporation and federation of worker cooperatives based in the Basque region of Spain. It was founded in the town of Mondragon in 1956 by graduates of a local technical college. Its first product was paraffin heaters. It is the tenth-largest Spanish company in terms of asset turnover and the leading business group in the Basque Country. At the end of 2014, it employed 74,117 people in 257 companies and organizations in four areas of activity: finance, industry, retail and knowledge. By 2015, 74,335 people were employed. Mondragon cooperatives operate in accordance with the Statement on the Co-operative Identity maintained by the International Co-operative Alliance.

🔗 Computing 🔗 Classical Greece and Rome 🔗 Greece 🔗 Astronomy 🔗 History of Science 🔗 Alternative Views 🔗 Time

The Antikythera mechanism (, ) is an ancient hand powered Greek analogue computer which has also been described as the first example of such device used to predict astronomical positions and eclipses for calendar and astrological purposes decades in advance. It could also be used to track the four-year cycle of athletic games which was similar to an Olympiad, the cycle of the ancient Olympic Games.

This artefact was retrieved from the sea in 1901, and identified on 17 May 1902 as containing a gear by archaeologist Valerios Stais, among wreckage retrieved from a shipwreck off the coast of the Greek island Antikythera. The instrument is believed to have been designed and constructed by Greek scientists and has been variously dated to about 87 BC, or between 150 and 100 BC, or to 205 BC, or to within a generation before the shipwreck, which has been dated to approximately 70–60 BC.

The device, housed in the remains of a 34 cm × 18 cm × 9 cm (13.4 in × 7.1 in × 3.5 in) wooden box, was found as one lump, later separated into three main fragments which are now divided into 82 separate fragments after conservation efforts. Four of these fragments contain gears, while inscriptions are found on many others. The largest gear is approximately 14 centimetres (5.5 in) in diameter and originally had 223 teeth.

It is a complex clockwork mechanism composed of at least 30 meshing bronze gears. A team led by Mike Edmunds and Tony Freeth at Cardiff University used modern computer x-ray tomography and high resolution surface scanning to image inside fragments of the crust-encased mechanism and read the faintest inscriptions that once covered the outer casing of the machine.

Detailed imaging of the mechanism suggests that it had 37 gear wheels enabling it to follow the movements of the Moon and the Sun through the zodiac, to predict eclipses and even to model the irregular orbit of the Moon, where the Moon's velocity is higher in its perigee than in its apogee. This motion was studied in the 2nd century BC by astronomer Hipparchus of Rhodes, and it is speculated that he may have been consulted in the machine's construction.

The knowledge of this technology was lost at some point in antiquity. Similar technological works later appeared in the medieval Byzantine and Islamic worlds, but works with similar complexity did not appear again until the development of mechanical astronomical clocks in Europe in the fourteenth century. All known fragments of the Antikythera mechanism are now kept at the National Archaeological Museum in Athens, along with a number of artistic reconstructions and replicas of the mechanism to demonstrate how it may have looked and worked.

🔗 Military history 🔗 Military history/North American military history 🔗 Military history/United States military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry

The demon core was a spherical 6.2-kilogram (14 lb) subcritical mass of plutonium 89 millimetres (3.5 in) in diameter, that was involved in two criticality accidents, on August 21, 1945 and May 21, 1946. The core was intended for use in a third nuclear weapon, but remained in use for testing after Japan's surrender. It was designed with a small safety margin to ensure a successful explosion of the bomb. The device briefly went supercritical when it was accidentally placed in supercritical configurations during two separate experiments intended to guarantee the core was indeed close to the critical point. The incidents happened at the Los Alamos Laboratory in 1945 and 1946, both resulting in the acute radiation poisoning and subsequent deaths of scientists: Harry Daghlian and Louis Slotin. After these incidents the spherical plutonium core was referred to as the "demon core".

🔗 Maps

In cartography, a trap street is a fictitious entry in the form of a misrepresented street on a map, often outside the area the map nominally covers, for the purpose of "trapping" potential copyright violators of the map who, if caught, would be unable to explain the inclusion of the "trap street" on their map as innocent. On maps that are not of streets, other "copyright trap" features (such as nonexistent towns, or mountains with the wrong elevations) may be inserted or altered for the same purpose.

Trap streets are often nonexistent streets; but sometimes, rather than actually depicting a street where none exists, a map will misrepresent the nature of a street in a fashion that can still be used to detect copyright violators but is less likely to interfere with navigation. For instance, a map might add nonexistent bends to a street, or depict a major street as a narrow lane, without changing its location or its connections to other streets.

Trap streets are rarely acknowledged by publishers. One known case is a popular driver's atlas for the city of Athens, Greece, which has a warning inside its front cover that potential copyright violators should beware of trap streets.

🔗 Fungi 🔗 Weather 🔗 Weather/Weather

Hair ice, also known as ice wool or frost beard, is a type of ice that forms on dead wood and takes the shape of fine, silky hair. It is somewhat uncommon, and has been reported mostly at latitudes between 45–55 °N in broadleaf forests. The meteorologist and discoverer of continental drift, Alfred Wegener, described hair ice on wet dead wood in 1918, assuming some specific fungi as the catalyst, a theory mostly confirmed by Gerhart Wagner and Christian Mätzler in 2005. In 2015, the fungus Exidiopsis effusa was identified as key to the formation of hair ice.

🔗 Organizations 🔗 Engineering

The Iron Ring is a ring worn by many Canadian-trained engineers, as a symbol and reminder of the obligations and ethics associated with their profession. The ring is presented to engineering graduates in a private ceremony known as the Ritual of the Calling of an Engineer. The concept of the ritual and its Iron Rings originated from H. E. T. Haultain in 1922, with assistance from Rudyard Kipling, who crafted the ritual at Haultain's request.

🔗 Color

Pantone 448 C, also referred to as "the ugliest colour in the world", is a colour in the Pantone colour system. Described as a "drab dark brown", it was selected in 2016 as the colour for plain tobacco and cigarette packaging in Australia, after market researchers determined that it was the least attractive colour. The Australian Department of Health initially referred to the colour as "olive green", but the name was changed after concerns were expressed by the Australian Olive Association.

Since 2016, the same colour has also been used for plain cigarette packaging in France, the United Kingdom, Israel, Norway, New Zealand, Slovenia, Saudi Arabia, and Turkey.

The colour has also been widely but erroneously reported as being known as "opaque couché"; in fact this is simply French for "layered opaque", in reference to being used on coated paper. The confusion appears to have arisen because "PANTONE opaque couché" is the French name of a swatch library (palette) used in Adobe Illustrator containing this colour and intended for printing in solid ink colours on coated paper; in English this library is known as "PANTONE solid coated".

🔗 Mathematics 🔗 Maps

The coastline paradox is the counterintuitive observation that the coastline of a landmass does not have a well-defined length. This results from the fractal curve-like properties of coastlines, i.e., the fact that a coastline typically has a fractal dimension (which in fact makes the notion of length inapplicable). The first recorded observation of this phenomenon was by Lewis Fry Richardson and it was expanded upon by Benoit Mandelbrot.

The measured length of the coastline depends on the method used to measure it and the degree of cartographic generalization. Since a landmass has features at all scales, from hundreds of kilometers in size to tiny fractions of a millimeter and below, there is no obvious size of the smallest feature that should be taken into consideration when measuring, and hence no single well-defined perimeter to the landmass. Various approximations exist when specific assumptions are made about minimum feature size.

The problem is fundamentally different from the measurement of other, simpler edges. It is possible, for example, to accurately measure the length of a straight, idealized metal bar by using a measurement device to determine that the length is less than a certain amount and greater than another amount—that is, to measure it within a certain degree of uncertainty. The more accurate the measurement device, the closer results will be to the true length of the edge. When measuring a coastline, however, the closer measurement does not result in an increase in accuracy—the measurement only increases in length; unlike with the metal bar, there is no way to obtain a maximum value for the length of the coastline.

In three-dimensional space, the coastline paradox is readily extended to the concept of fractal surfaces whereby the area of a surface varies, depending on the measurement resolution.

🔗 Games

Nomic is a game created in 1982 by philosopher Peter Suber in which the rules of the game include mechanisms for the players to change those rules, usually beginning through a system of democratic voting.

Nomic is a game in which changing the rules is a move. In that respect it differs from almost every other game. The primary activity of Nomic is proposing changes in the rules, debating the wisdom of changing them in that way, voting on the changes, deciding what can and cannot be done afterwards, and doing it. Even this core of the game, of course, can be changed.

The initial ruleset was designed by Peter Suber, and first published in Douglas Hofstadter's column Metamagical Themas in Scientific American in June 1982. The column discussed Suber's then-upcoming book, The Paradox of Self-Amendment, which was published some years later. Nomic now refers to many games, all based on the initial ruleset.

The game is in some ways modeled on modern government systems. It demonstrates that in any system where rule changes are possible, a situation may arise in which the resulting laws are contradictory or insufficient to determine what is in fact legal. Because the game models (and exposes conceptual questions about) a legal system and the problems of legal interpretation, it is named after νόμος (nomos), Greek for "law".

While the victory condition in Suber's initial ruleset is the accumulation of 100 points by the roll of dice, he once said that "this rule is deliberately boring so that players will quickly amend it to please themselves". Players can change the rules to such a degree that points can become irrelevant in favor of a true currency, or make victory an unimportant concern. Any rule in the game, including the rules specifying the criteria for winning and even the rule that rules must be obeyed, can be changed. Any loophole in the ruleset, however, may allow the first player to discover it the chance to pull a "scam" and modify the rules to win the game. Complicating this process is the fact that Suber's initial ruleset allows for the appointment of judges to preside over issues of rule interpretation.

🔗 Australia 🔗 Australia/Western Australia 🔗 Australia/Australian biota 🔗 Spiders

Number 16 (c. 1974 – 2016), also known as #16, was a wild female trapdoor spider (Gaius villosus, family Idiopidae) that lived in North Bungulla Reserve near Tammin, Western Australia. She lived an estimated 43 years and became the longest-lived spider on record, beating a 28-year-old tarantula who previously held the title. When Number 16 finally died in 2016, it was not of old age but from a parasitic wasp sting.