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🔗 Late Bronze Age Collapse

🔗 Africa 🔗 Ancient Near East 🔗 Ancient Egypt 🔗 Greece 🔗 Turkey 🔗 Archaeology

The Late Bronze Age collapse was a dark age transition in a large area covering much of Southeast Europe, West Asia and North Africa (comprising the overlapping regions of the Near East, the Eastern Mediterranean and North Africa, with the Balkans, the Aegean, Anatolia, and the Caucasus), which took place from the Late Bronze Age to the emerging Early Iron Age. It was a transition which historians believe was violent, sudden, and culturally disruptive, and involved societal collapse for some civilizations during the 12th century BCE. The palace economy of Mycenaean Greece, the Aegean region and Anatolia that characterized the Late Bronze Age disintegrated, transforming into the small isolated village cultures of the Greek Dark Ages. The Hittite Empire of Anatolia and the Levant collapsed, while states such as the Middle Assyrian Empire in Mesopotamia and the New Kingdom of Egypt survived but were considerably weakened.

Competing and even mutually compatible theories for the ultimate cause of the Late Bronze Age collapse have been made since the 19th century. These include volcanic eruptions, droughts, invasions by the Sea Peoples or migrations of Dorians, economic disruptions due to the rising use of ironworking, and changes in military technology and methods of war that saw the decline of chariot warfare.

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🔗 Peirce Quincuncial Projection

🔗 Geography 🔗 Maps

The Peirce quincuncial projection is a conformal map projection developed by Charles Sanders Peirce in 1879. The projection has the distinctive property that it can be tiled ad infinitum on the plane, with edge-crossings being completely smooth except for four singular points per tile. The projection has seen use in digital photography for portraying 360° views. The description quincuncial refers to the arrangement of four quadrants of the globe around the center hemisphere in an overall square pattern. Typically the projection is oriented such that the north pole lies at the center.

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🔗 Uno – The “Unit” for Dimensionless Quantities

🔗 Measurement

In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they are pure numbers with no associated units of measurement. Commonly used are parts-per-million (ppm, 10−6), parts-per-billion (ppb, 10−9), parts-per-trillion (ppt, 10−12) and parts-per-quadrillion (ppq, 10−15). This notation is not part of the International System of Units (SI) system and its meaning is ambiguous.

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🔗 DCF77

🔗 Germany 🔗 Time 🔗 Radio Stations

DCF77 is a German longwave time signal and standard-frequency radio station. It started service as a standard-frequency station on 1 January 1959. In June 1973 date and time information was added. Its primary and backup transmitter are located at 50°0′56″N 9°00′39″E in Mainflingen, about 25 km south-east of Frankfurt am Main, Germany. The transmitter generates a nominal power of 50 kW, of which about 30 to 35 kW can be radiated via a T-antenna.

DCF77 is controlled by the Physikalisch-Technische Bundesanstalt (PTB), Germany's national physics laboratory and transmits in continuous operation (24 hours). It is operated by Media Broadcast GmbH (previously a subsidiary of Deutsche Telekom AG), on behalf of the PTB. With Media Broadcast GmbH, a temporal transmission availability of at least 99.7% per year or under 26.28 hours of annual downtime has been agreed upon. Most service interruptions are short-term disconnections of under two minutes. Longer lasting transmission service interruptions are generally caused by strong winds, freezing rain or snow-induced T-antenna movement. This manifests itself in electrical detuning of the antenna resonance circuit and hence a measurable phase modulation of the received signal. When the maladjustment is too large, the transmitter is taken out of service temporarily. In the year 2002, almost 99.95% availability, or just over 4.38 hours of downtime, was realized. The timestamp sent is either in Coordinated Universal Time (UTC)+1 or UTC+2 depending on daylight saving time.

The highly accurate 77.5 kHz (approximately 3868.3 m wavelength) carrier signal is generated from local atomic clocks that are linked with the German master clocks at the PTB in Braunschweig. The DCF77 time signal is used for the dissemination of the German national legal time to the public.

Radio clocks and watches have been very popular in Europe since the late 1980s and, in mainland Europe, most of them use the DCF77 signal to set their time automatically. Further industrial time-keeping systems at railway stations, in the field of telecommunication and information technology, and at radio and TV stations are radio-controlled by DCF77 as well as tariff change-over clocks of energy supply companies and clocks in traffic-light facilities.

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  • "DCF77" | 2021-06-30 | 67 Upvotes 37 Comments

🔗 Bob's Game

🔗 Video games

Bob's Game (stylized as "bob's game") was a role-playing video game being developed by independent video game developer Robert Pelloni since 2003/2004. The project is most notable for Pelloni developing the game using open source software development tools and Nintendo's refusal to license him the official SDK as well as Bob's response to that decision.

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🔗 Public Universal Friend

🔗 United States 🔗 Biography 🔗 Women's History 🔗 Christianity 🔗 Gender Studies 🔗 United States/Rhode Island 🔗 Christianity/Religious Society of Friends (Quakers)

The Public Universal Friend (born Jemima Wilkinson; November 29, 1752 – July 1, 1819) was an American preacher born in Cumberland, Rhode Island, to Quaker parents. After suffering a severe illness in 1776, the Friend claimed to have died and been reanimated as a genderless evangelist named the Public Universal Friend, and afterward shunned both birth name and gendered pronouns. In androgynous clothes, the Friend preached throughout the northeastern United States, attracting many followers who became the Society of Universal Friends.

The Public Universal Friend's theology was broadly similar to that of most Quakers. The Friend stressed free will, opposed slavery, and supported sexual abstinence. The most committed members of the Society of Universal Friends were a group of unmarried women who took leading roles in their households and community. In the 1790s, members of the Society acquired land in Western New York where they formed the township of Jerusalem near Penn Yan, New York. The Society of Universal Friends ceased to exist by the 1860s. Many writers have portrayed the Friend as a woman, and either a manipulative fraudster, or a pioneer for women's rights; others have viewed the preacher as transgender or non-binary and a figure in trans history.

🔗 Naumachia

The naumachia (in Latin naumachia, from the Ancient Greek ναυμαχία/naumachía, literally "naval combat") in the Ancient Roman world referred to both the staging of naval battles as mass entertainment, and the basin or building in which this took place.

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🔗 Diderot Effect

🔗 Environment 🔗 Marketing & Advertising 🔗 Anthropology 🔗 Environment/Sustainability

The Diderot effect is a social phenomenon related to consumer goods. It is based on two ideas. The first idea is that goods purchased by consumers will align with their sense of identity, and, as a result, will complement one another. The second idea states that the introduction of a new possession that deviates from the consumer's current complementary goods can result in a process of spiraling consumption. The term was coined by anthropologist and scholar of consumption patterns Grant McCracken in 1988, and is named after the French philosopher Denis Diderot (1713–1784), who first described the effect in an essay.

The term has become common in discussions of sustainable consumption and green consumerism, in regard to the process whereby a purchase or gift creates dissatisfaction with existing possessions and environment, provoking a potentially spiraling pattern of consumption with negative environmental, psychological, and social impacts.

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🔗 List of Military Nuclear Accidents

🔗 Military history 🔗 Disaster management 🔗 Military history/Military science, technology, and theory 🔗 Military history/Weaponry 🔗 Energy

This article lists notable military accidents involving nuclear material. Civilian accidents are listed at List of civilian nuclear accidents. For a general discussion of both civilian and military accidents, see nuclear and radiation accidents. For other lists, see Lists of nuclear disasters and radioactive incidents.

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🔗 Moose: Man Out of Space Easiest

🔗 Spaceflight

MOOSE, originally an acronym for Man Out Of Space Easiest but later changed to the more professional-sounding Manned Orbital Operations Safety Equipment, was a proposed emergency "bail-out" system capable of bringing a single astronaut safely down from Earth orbit to the planet's surface. The design was proposed by General Electric in the early 1960s. The system was quite compact, weighing 200 lb (91 kg) and fitting inside a suitcase-sized container. It consisted of a small twin-nozzle rocket motor sufficient to deorbit the astronaut, a PET film bag 6 ft (1.8 m) long with a flexible 0.25 in (6.4 mm) ablative heat shield on the back, two pressurized canisters to fill it with polyurethane foam, a parachute, radio equipment and a survival kit.

The astronaut would leave the vehicle in a space suit, climb inside the plastic bag, and then fill it with foam. The bag had the shape of a blunt cone, with the astronaut embedded in its base facing the apex of the cone. The rocket pack would protrude from the bag and be used to slow the astronaut's orbital speed enough so that he would reenter Earth's atmosphere, and the foam-filled bag would act as insulation during the subsequent aerobraking. Finally, once the astronaut had descended to 30,000 ft (9.1 km) where the air was sufficiently dense, the parachute would automatically deploy and slow the astronaut's fall to 17 mph (7.6 m/s). The foam heat shield would serve a final role as cushioning when the astronaut touched down and as a flotation device should they land on water. The radio beacon would guide rescuers.

General Electric performed preliminary testing on some of the components of the MOOSE system, including flying samples of heat shield material on a Mercury mission, inflating a foam-filled bag with a human subject embedded inside, and test-dropping dummies and a human subject in MOOSE foam shields short distances. U.S. Air Force Capt. Joe Kittinger's historic freefall from a balloon at 103,000 ft (31,000 m) in August 1960 also helped demonstrate the feasibility of such extreme parachuting. However, the MOOSE system was nonetheless always intended as an extreme emergency measure when no other option for returning an astronaut to Earth existed; falling from orbit protected by nothing more than a spacesuit and a bag of foam was unlikely to ever become a particularly safe—or enticing—maneuver.

Neither NASA nor the U.S. Air Force expressed an interest in the MOOSE system, and so by the end of the 1960s the program had been quietly shelved.

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