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🔗 France 🔗 Middle Ages 🔗 Middle Ages/History

The Bal des Ardents (Ball of the Burning Men) or Bal des Sauvages (Ball of the Wild Men) was a masquerade ball held on 28 January 1393 in Paris at which Charles VI of France performed in a dance with five members of the French nobility. Four of the dancers were killed in a fire caused by a torch brought in by a spectator, Charles's brother Louis I, Duke of Orléans. Charles and another of the dancers survived. The ball was one of a number of events intended to entertain the young king, who the previous summer had suffered an attack of insanity. The event undermined confidence in Charles's capacity to rule; Parisians considered it proof of courtly decadence and threatened to rebel against the more powerful members of the nobility. The public's outrage forced the king and his brother Orléans, whom a contemporary chronicler accused of attempted regicide and sorcery, to offer penance for the event.

Charles's wife, Isabeau of Bavaria, held the ball to honor the remarriage of a lady-in-waiting. Scholars believe the dance performed at the ball had elements of traditional charivari, with the dancers disguised as wild men, mythical beings often associated with demonology, that were commonly represented in medieval Europe and documented in revels of Tudor England. The event was chronicled by contemporary writers such as the Monk of St Denis and Jean Froissart, and illustrated in a number of 15th-century illuminated manuscripts by painters such as the Master of Anthony of Burgundy. The incident later provided inspiration for Edgar Allan Poe's short story Hop-Frog.

🔗 Role-playing games

GNS theory is an informal field of study developed by Ron Edwards which attempts to create a unified theory of how role-playing games work. Focused on player behavior, in GNS theory participants in role-playing games organize their interactions around three categories of engagement: Gamism, Narrativism and Simulation.

The theory focuses on player interaction rather than statistics, encompassing game design beyond role-playing games. Analysis centers on how player behavior fits the above parameters of engagement and how these preferences shape the content and direction of a game. GNS theory is used by game designers to dissect the elements which attract players to certain types of games.

🔗 Novels

The 480 is a political fiction novel by Eugene Burdick (1964).

The plot evolves around the political turmoil after John F. Kennedy assassination in 1963. In the novel, a fictitious charismatic character, John Thatch, an engineer, is seeking nomination for the Republican Party candidate at 1964 presidential elections. He is described as being contaminated with the "political virus". A handful of political professionals are promoting his nomination, in confrontation with the Party establishment. There exist apparent parallels between Thatch and Henry Cabot Lodge, Jr., a write-in hero at New Hampshire primary.

The novel criticizes the socio-political effects on society at large from the use of computers to run massive simulations, which predict the public reaction to certain (proposed) political moves before implementing them. Such simulations make it easy to manipulate the public consciousness.

The "480" in the title denotes the number of groups (by party affiliation, socioeconomic status, location, origin, etc.) that the computer simulation uses to classify the American electorate. The full list of these is reproduced in the Appendix, claimed by the author to be the true list used by the Simulmatics Corporation (real name) in Senator John F. Kennedy's Presidential campaign in 1960. The cover features an IBM 5081 punched card.

The Simulmatics Corporation was created by MIT Professor Ithiel de Sola Pool, who provided a non-fiction backup to "The 480" in "Candidates, Issues, and Strategies: A Computer Simulation of the 1960 Presidential Election," MIT Press, 1964 (with co-authors Robert P. Abelson and Samuel L. Popkin). They built their model from 130,000 archived interviews in Gallup and Roper polls over a ten-year period. Based on its output, they advised Kennedy that he would benefit from a strong civil rights stand and that he had nothing to lose, and much to gain, by attacking religious bigotry and dealing frankly with his Catholicism.

The 480 has been cited as prefiguring the effect of modern social media and data gathering on politics.

🔗 Mathematics 🔗 Physics

The Fresnel integrals S(x) and C(x) are two transcendental functions named after Augustin-Jean Fresnel that are used in optics and are closely related to the error function (erf). They arise in the description of near-field Fresnel diffraction phenomena and are defined through the following integral representations:

The simultaneous parametric plot of S(x) and C(x) is the Euler spiral (also known as the Cornu spiral or clothoid).

🔗 France 🔗 Military history 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Brands 🔗 Military history/French military history 🔗 Military history/Military land vehicles 🔗 Military history/Italian military history 🔗 Military history/European military history

The Vespa 150 TAP was an anti-tank scooter made in the 1950s from a Vespa scooter for use with French paratroops (troupes aéroportées, TAP). Introduced in 1956 and updated in 1959, the scooter was produced by Ateliers de Construction de Motocycles et Automobiles (ACMA), the licensed assembler of Vespas in France at the time. Modifications from the civilian Vespa included a reinforced frame and a 75 mm (3.0 in) recoilless rifle mounted to the scooter.

The 150 TAPs mounted a M20 75 mm recoilless rifle, a U.S.-made light anti-armour weapon. It was very light in comparison to a standard 75 mm (3.0 in) cannon but was still able to penetrate 100 mm (3.9 in) of armour with its HEAT warhead. The recoil was counteracted by venting propellant gases out the rear of the weapon which eliminated the need for a mechanical recoil system or heavy mount.

The scooters would be parachute-dropped in pairs, accompanied by a two-man team. The gun was carried on one scooter, while the ammunition was loaded on the other. Due to the lack of any kind of aiming devices the recoilless rifle was never designed to be fired from the scooter; the gun was mounted on a M1917 Browning machine gun tripod, which was also carried by the scooter, before being fired. However, in an emergency it could be fired while in the frame, and while the scooter was moving.

The "Bazooka Vespa" was relatively cheap: Vespas cost roughly US$500 at the time, and the M20s were plentiful. 600 of them were produced, between 1956 and 1959. It had a cart, and also came with two cans of fuel.

The scooter themselves were original civilian produced VB1T models, 150 cc capacity engine. The engine was two stroke, top speed of 60 km/h (37 mph), enough speed to ram any vehicles if needed in an emergency, or move the user from the drop site to the area where the paratrooper was needed.

🔗 Economics

Baumol's cost disease (or the Baumol effect) is the rise of salaries in jobs that have experienced no or low increase of labor productivity, in response to rising salaries in other jobs that have experienced higher labor productivity growth. This pattern seemingly goes against the theory in classical economics in which real wage growth is closely tied to labor productivity changes. The phenomenon was described by William J. Baumol and William G. Bowen in the 1960s.

The rise of wages in jobs without productivity gains is from the requirement to compete for employees with jobs that have experienced gains and so can naturally pay higher salaries, just as classical economics predicts. For instance, if the retail sector pays its managers 19th-century-style salaries, the managers may decide to quit to get a job at an automobile factory, where salaries are higher because of high labor productivity. Thus, managers' salaries are increased not by labor productivity increases in the retail sector but by productivity and corresponding wage increases in other industries.

🔗 Philosophy 🔗 Skepticism 🔗 Philosophy/Logic 🔗 Psychology 🔗 Cognitive science

A cognitive bias is a systematic pattern of deviation from norm or rationality in judgment. Individuals create their own "subjective reality" from their perception of the input. An individual's construction of reality, not the objective input, may dictate their behavior in the world. Thus, cognitive biases may sometimes lead to perceptual distortion, inaccurate judgment, illogical interpretation, or what is broadly called irrationality.

Some cognitive biases are presumably adaptive. Cognitive biases may lead to more effective actions in a given context. Furthermore, allowing cognitive biases enables faster decisions which can be desirable when timeliness is more valuable than accuracy, as illustrated in heuristics. Other cognitive biases are a "by-product" of human processing limitations, resulting from a lack of appropriate mental mechanisms (bounded rationality), impact of individual's constitution and biological state (see embodied cognition), or simply from a limited capacity for information processing.

A continually evolving list of cognitive biases has been identified over the last six decades of research on human judgment and decision-making in cognitive science, social psychology, and behavioral economics. Daniel Kahneman and Tversky (1996) argue that cognitive biases have efficient practical implications for areas including clinical judgment, entrepreneurship, finance, and management.

🔗 California 🔗 California/San Francisco Bay Area 🔗 Crime

On April 16, 2013, a sophisticated assault was carried out on Pacific Gas and Electric Company's Metcalf Transmission Substation in Coyote, California, near the border of San Jose. The attack, in which gunmen fired on 17 electrical transformers, resulted in more than $15 million worth of equipment damage, but it had little impact on the station's electrical power supply.

🔗 Environment 🔗 Energy

Pumped-storage hydroelectricity (PSH), or pumped hydroelectric energy storage (PHES), is a type of hydroelectric energy storage used by electric power systems for load balancing. The method stores energy in the form of gravitational potential energy of water, pumped from a lower elevation reservoir to a higher elevation. Low-cost surplus off-peak electric power is typically used to run the pumps. During periods of high electrical demand, the stored water is released through turbines to produce electric power.

Pumped-storage hydroelectricity allows energy from intermittent sources (such as solar, wind) and other renewables, or excess electricity from continuous base-load sources (such as coal or nuclear) to be saved for periods of higher demand. The reservoirs used with pumped storage can be quite small when contrasted with the lakes of conventional hydroelectric plants of similar power capacity, and generating periods are often less than half a day.

The round-trip efficiency of PSH generally varies between 70%–80%. Although the losses of the pumping process make the plant a net consumer of energy overall, the system increases revenue by selling more electricity during periods of peak demand, when electricity prices are highest. If the upper lake collects significant rainfall or is fed by a river then the plant may be a net energy producer in the manner of a traditional hydroelectric plant.

Pumped storage is by far the largest-capacity form of grid energy storage available, and, as of 2020, PSH accounts for around 95% of all active storage installations worldwide, with a total installed throughput capacity of over 181 GW and a total installed storage capacity of over 1.6 TWh.

The main requirement for PSH is hilly country. The global greenfield pumped hydro atlas lists more than 600,000 potential sites around the world, which is about 100 times more than needed to support 100% renewable electricity. Most are closed-loop systems away from rivers. Areas of natural beauty and new dams on rivers can be avoided because of the very large number of potential sites. Some projects utilise existing reservoirs (dubbed "bluefield") such as the 350 Gigawatt-hour Snowy 2.0 scheme under construction in Australia. Some recently proposed projects propose to take advantage of "brownfield" locations such as disused mines such as the Kidston project under construction in Australia.

Water requirements for PSH are small: about 1 gigalitre of initial fill water per gigawatt-hour of storage. This water is recycled uphill and back downhill between the two reservoirs for many decades, but evaporation losses (beyond what rainfall and any inflow from local waterways provide) must be replaced. Land requirements are also small: about 10 hectares per gigawatt-hour of storage, which is much smaller than the land occupied by the solar and windfarms that the storage might support. Closed loop (off-river) pumped hydro storage has the smallest carbon emissions per unit of storage of all candidates for large-scale energy storage.

🔗 Paranormal 🔗 Scientology

Xenu (), also called Xemu, was, according to Scientology founder L. Ron Hubbard, the dictator of the "Galactic Confederacy" who brought billions of his people to Earth (then known as "Teegeeack") in DC-8-like spacecraft 75 million years ago, stacked them around volcanoes, and killed them with hydrogen bombs. Official Scientology scriptures hold that the thetans (immortal spirits) of these aliens adhere to humans, causing spiritual harm.

These events are known within Scientology as "Incident II", and the traumatic memories associated with them as "The Wall of Fire" or "R6 implant". The narrative of Xenu is part of Scientologist teachings about extraterrestrial civilizations and alien interventions in earthly events, collectively described as "space opera" by Hubbard. Hubbard detailed the story in Operating Thetan level III (OT III) in 1967, warning that the "R6 implant" (past trauma) was "calculated to kill (by pneumonia, etc.) anyone who attempts to solve it".

Within the Church of Scientology, the Xenu story is part of the church's secret "Advanced Technology", considered a sacred and esoteric teaching, which is normally only revealed to members who have completed a lengthy sequence of courses costing large amounts of money. The church avoids mention of Xenu in public statements and has gone to considerable effort to maintain the story's confidentiality, including legal action on the grounds of copyright and trade secrecy. Officials of the Church of Scientology widely deny or try to hide the Xenu story. Despite this, much material on Xenu has leaked to the public via court documents and copies of Hubbard's notes that have been distributed through the Internet. In commentary on the impact of the Xenu text, academic scholars have discussed and analyzed the writings by Hubbard and their place within Scientology within the contexts of science fiction, UFO religions, Gnosticism and creation myths.