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🔗 Lists 🔗 Martial arts 🔗 Sumo

Kimarite (決まり手, "Deciding technique") are winning techniques in a sumo bout. For each bout in a Grand Sumo tournament (or honbasho), a sumo referee, or gyōji, will decide and announce the type of kimarite used by the winner. It is possible (although rare) for the judges to modify this decision later. Records of the kimarite are kept and statistical information on the preferred techniques of different wrestlers can be deduced easily. For example, a pie chart of the kimarite used by each sekitori in the past year can be found on the Japan Sumo Association webpage.

Since 2001, the Japan Sumo Association recognizes 82 types of kimarite (and 5 winning non-techniques), but only about a dozen are used regularly. For example, yorikiri, oshidashi and hatakikomi are frequent methods used to win bouts. In addition to kimarite, a bout can end in a disqualification if either wrestler makes a foul (禁手, kinjite), such as striking with a closed fist.

The following is a full list of kimarite. Literal translations of the Japanese are also given.

🔗 Computing 🔗 Denmark 🔗 Food and drink 🔗 Beer

Free Beer, originally known as Vores øl - An open source beer (Danish for: Our Beer), is the first brand of beer with an "open"/"free" brand and recipe. The recipe and trademark elements are published under the Creative Commons CC BY-SA license.

The beer was created in 2004 by students at the IT University in Copenhagen together with artist collective Superflex, to illustrate how concepts of the FOSS movement might be applied outside the digital world. The "Free Beer" concept illustrates also the connection between the long tradition of freely sharing cooking recipes with the FOSS movement, which tries to establish this sharing tradition also for the "recipes" of software, the source code. The "Free beer" concept received an overall positive reception from international press and media for the political message, was presented on many exhibitions and conferences, and inspired many breweries in adopting the concept.

🔗 Spaceflight

A porkchop plot (also pork-chop plot) is a chart that shows contours of equal characteristic energy (C₃) against combinations of launch date and arrival date for a particular interplanetary flight.

By examining the results of the porkchop plot, engineers can determine when launch opportunities exist (a launch window) that is compatible with the capabilities of a particular spacecraft. A given contour, called a porkchop curve, represents constant C₃, and the center of the porkchop the optimal minimum C₃. The orbital elements of the solution, where the fixed values are the departure date, the arrival date, and the length of the flight, were first solved mathematically in 1761 by Johann Heinrich Lambert, and the equation is generally known as Lambert's problem (or theorem).

🔗 Computing 🔗 Computer science

Note G was a computer algorithm written by Ada Lovelace, and was designed to calculate Bernoulli numbers using the hypothetical analytical engine. Note G is generally agreed to be the first algorithm specifically for a computer, and Lovelace is considered as the first computer programmer as a result. The algorithm was the last note in a series labelled A to G, which she employed as visual aids to accompany her English translation of Luigi Menabrea's 1842 French transcription of Charles Babbage's lecture on the analytical engine at the University of Turin, "Notions sur la machine analytique de Charles Babbage" ("Elements of Charles Babbage’s Analytical Machine"). Lovelace's Note G was never tested, as the engine was never built. Her notes, along with her translation, were published in 1843.

In the modern era, thanks to more readily available computing equipment and programming resources, Lovelace's algorithm has since been tested, after being "translated" into modern programming languages. These tests have independently concluded that there was a bug in the script, due to a minor typographical error, rendering the algorithm in its original state unusable.

🔗 Computing

A long-running debate in computer science known as the Protocol Wars occurred from the 1970s to the 1990s when engineers, organizations and nations became polarized over the issue of which communication protocol would result in the best and most robust computer networks. This culminated in the Internet–OSI Standards War in the late 1980s and early 1990s, which was ultimately "won" by the Internet protocol suite ("TCP/IP") by the mid-1990s and has since resulted in most other protocols disappearing.

The pioneers of packet switching technology built computer networks to research data communications in the early 1970s. As public data networks emerged in the mid to late 1970s, the debate about interface standards was described as a "battle for access standards". An international collaboration between several national postal, telegraph and telephone ("PTT") providers and commercial operators developed the X.25 standard in 1976, which was adopted on public networks providing global coverage. Several proprietary standards also emerged, most notably IBM's Systems Network Architecture.

The United States Department of Defense developed and tested TCP/IP during the 1970s in collaboration with universities and researchers in the United States, United Kingdom and France. IPv4 was released in 1981 and the DoD made it standard for all military computer networking. By 1984, an international reference model known as the OSI model had been agreed on, with which TCP/IP was not compatible. Many governments in Europe – particularly France, West Germany, the United Kingdom and the European Economic Community – and also the United States Department of Commerce mandated compliance with the OSI model and the US Department of Defense planned to transition away from TCP/IP to OSI.

Meanwhile, the development of a complete Internet protocol suite by 1989, and partnerships with the telecommunication and computer industry to incorporate TCP/IP software into various operating systems laid the foundation for the widespread adoption of TCP/IP as a comprehensive protocol suite. While OSI developed its networking standards in the late 1980s, TCP/IP came into widespread use on multi-vendor networks for internetworking and as the core component of the emerging Internet.

🔗 Computing

Reservoir computing is a framework for computation that may be viewed as an extension of neural networks. Typically an input signal is fed into a fixed (random) dynamical system called a reservoir and the dynamics of the reservoir map the input to a higher dimension. Then a simple readout mechanism is trained to read the state of the reservoir and map it to the desired output. The main benefit is that training is performed only at the readout stage and the reservoir is fixed. Liquid-state machines and echo state networks are two major types of reservoir computing. One important feature of this system is that it can use the computational power of naturally available systems which is different from the neural networks and it reduces the computational cost.

🔗 Music theory 🔗 Tunings, Temperaments, and Scales

In music theory, the circle of fifths (or circle of fourths) is the relationship among the 12 tones of the chromatic scale, their corresponding key signatures, and the associated major and minor keys. More specifically, it is a geometrical representation of relationships among the 12 pitch classes of the chromatic scale in pitch class space.

🔗 Physics

In quantum field theory, the Casimir effect and the Casimir–Polder force are physical forces arising from a quantized field. They are named after the Dutch physicist Hendrik Casimir who predicted them in 1948.

The Casimir effect can be understood by the idea that the presence of conducting metals and dielectrics alters the vacuum expectation value of the energy of the second quantized electromagnetic field. Since the value of this energy depends on the shapes and positions of the conductors and dielectrics, the Casimir effect manifests itself as a force between such objects.

Any medium supporting oscillations has an analogue of the Casimir effect. For example, beads on a string as well as plates submerged in turbulent water or gas illustrate the Casimir force.

In modern theoretical physics, the Casimir effect plays an important role in the chiral bag model of the nucleon; in applied physics it is significant in some aspects of emerging microtechnologies and nanotechnologies.

🔗 Environment 🔗 Meteorology 🔗 Astronomy 🔗 Middle Ages 🔗 Middle Ages/History 🔗 Geology 🔗 Glaciers 🔗 Solar System

The 774–775 carbon-14 spike is an observed increase of 1.2% in the concentration of carbon-14 isotope in tree rings dated to 774 or 775, which is about 20 times as high as the normal background rate of variation. It was discovered during a study of Japanese cedar trees, with the year of occurrence determined through dendrochronology. A surge in beryllium isotope ¹⁰
Be, detected in Antarctic ice cores, has also been associated with the 774–775 event. It is known as the Miyake event or the Charlemagne event and it produced the largest and most rapid rise in carbon-14 ever recorded.

The event appears to have been global, with the same carbon-14 signal found in tree rings from Germany, Russia, the United States, Finland and New Zealand.

The signal exhibits a sharp increase of around 1.2% followed by a slow decline (see Figure 1), which is typical for an instant production of carbon-14 in the atmosphere, indicating that the event was short in duration. The globally averaged production of carbon-14 for this event is calculated as Q = 1.3×10⁸ ± 0.2×10⁸ atoms/cm².

🔗 Computer science 🔗 Systems 🔗 Systems/Scientific modeling

Jackson structured programming (JSP) is a method for structured programming developed by British software consultant Michael A. Jackson and described in his 1975 book Principles of Program Design. The technique of JSP is to analyze the data structures of the files that a program must read as input and produce as output, and then produce a program design based on those data structures, so that the program control structure handles those data structures in a natural and intuitive way.

JSP describes structures (of both data and programs) using three basic structures – sequence, iteration, and selection (or alternatives). These structures are diagrammed as (in effect) a visual representation of a regular expression.