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🔗 XJACK PC Card Ethernet Connector

🔗 Computing

In laptop computing, the XJACK is a type of extendable connector or antenna for a type II PC card, designed by the Megahertz subsidiary of 3Com. When not in use, the XJACK retracts into the PC card for storage.

The XJACK was originally used in modem and network cards, to attach a standard RJ11 or 8P8C plug directly to the PC card. They do not require a separate dongle, which could be lost or misplaced, and do not need to be removed from the laptop when travelling. An alternative approach is to use larger type III cards with a regular modular connector socket, but this approach requires more space.

Wi-Fi PC cards for accessing wireless networks have an external portion containing the antenna for improved reception (as compared with inside the laptop), but this portion of the card may be accidentally damaged while moving the laptop. 3Com manufactured wireless cards with retractable antenna portions, also under the XJACK name. Other companies have since manufactured wireless cards with retractable antennas.

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🔗 Iron Gall Ink

🔗 Visual arts

Iron gall ink (also known as common ink, standard ink, oak gall ink or iron gall nut ink) is a purple-black or brown-black ink made from iron salts and tannic acids from vegetable sources. It was the standard ink formulation used in Europe for the 1400-year period between the 5th and 19th centuries, remained in widespread use well into the 20th century, and is still sold today.

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🔗 Floral formula

🔗 Plants

A floral formula is a notation for representing the structure of particular types of flowers. Such notations use numbers, letters and various symbols to convey significant information in a compact form. They may represent the floral form of a particular species, or may be generalized to characterize higher taxa, usually giving ranges of numbers of organs. Floral formulae are one of the two ways of describing flower structure developed during the 19th century, the other being floral diagrams. The format of floral formulae differs according to the tastes of particular authors and periods, yet they tend to convey the same information.

A floral formula is often used along with a floral diagram.

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🔗 A game theory behind the dark forest strategy?

🔗 China 🔗 Novels 🔗 Novels/Science fiction 🔗 Science Fiction

The Dark Forest (Chinese: 黑暗森林) is a 2008 science fiction novel by the Chinese writer Liu Cixin. It is the sequel to the Hugo Award-winning novel The Three-Body Problem in the trilogy titled Remembrance of Earth's Past, but Chinese readers generally refer to the series by the title of the first novel. The English version, translated by Joel Martinsen, was published in 2015. The novel is about the dark forest hypothesis (which was named after the novel), a possible solution to the Fermi paradox, though similar theories have been described as early as 1983.

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🔗 Pizza in North Korea

🔗 Korea 🔗 Food and drink 🔗 Korea/North Korea

North Korea has several restaurants serving pizza. Most people in the country cannot afford pizza, and it is mostly available for the elite. Pyongyang has five restaurants that serve pizza, including Pizza Restaurant on Kwangbok Street and Italy Pizza on Mirae Scientists Street. Kim Jong Il hired Italian chefs to train North Koreans in pizza making and introduced it to the country.

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🔗 Hofstede's Cultural Dimensions Theory

🔗 Psychology 🔗 Sociology 🔗 Media

Hofstede's cultural dimensions theory is a framework for cross-cultural psychology, developed by Geert Hofstede. It shows the effects of a society's culture on the values of its members, and how these values relate to behavior, using a structure derived from factor analysis.

Hofstede developed his original model as a result of using factor analysis to examine the results of a worldwide survey of employee values by IBM between 1967 and 1973. It has been refined since. The original theory proposed four dimensions along which cultural values could be analyzed: individualism-collectivism; uncertainty avoidance; power distance (strength of social hierarchy) and masculinity-femininity (task-orientation versus person-orientation). The Hofstede Cultural Dimensions factor analysis is based on extensive cultural preferences research conducted by Gert Jan Hofstede and his research teams. Hofstede based his research on national cultural preferences rather than individual cultural preferences. Hofstede included six key aspects of national culture country comparison scales, including: the power distance index (PDI), individualism vs. collectivism (IDV), motivation towards achievement and success (MAS, formerly masculinity versus femininity), uncertainty avoidance index (UAI), long term orientation versus short term normative orientation (LTO), and indulgence versus restraint (IVR). The PDI describes the degree to which authority is accepted and followed. The IDV measures the extent to which people look out for each other as a team or look out for themselves as an individual. MAS represents specific values that a society values. The UAI describes to what extent nations avoid the unknown. LTO expresses how societies either prioritize traditions or seek for the modern in their dealings with the present and the future. The IVR index is a comparison between a country's willingness to wait for long-term benefits by holding off on instant gratification, or preferences to no restraints on enjoying life at the present.

Independent research in Hong Kong led Hofstede to add a fifth dimension, long-term orientation, to cover aspects of values not discussed in the original paradigm. In 2010, Hofstede added a sixth dimension, indulgence versus self-restraint. Hofstede's work established a major research tradition in cross-cultural psychology and has also been drawn upon by researchers and consultants in many fields relating to international business and communication. The theory has been widely used in several fields as a paradigm for research, particularly in cross-cultural psychology, international management, and cross-cultural communication. It continues to be a major resource in cross-cultural fields.

🔗 Slide rule: One of the simplest forms of analog computer

🔗 Technology 🔗 Computing 🔗 Mathematics

A slide rule is a hand-operated mechanical calculator consisting of slidable rulers for evaluating mathematical operations such as multiplication, division, exponents, roots, logarithms, and trigonometry. It is one of the simplest analog computers.

Slide rules exist in a diverse range of styles and generally appear in a linear, circular or cylindrical form. Slide rules manufactured for specialized fields such as aviation or finance typically feature additional scales that aid in specialized calculations particular to those fields. The slide rule is closely related to nomograms used for application-specific computations. Though similar in name and appearance to a standard ruler, the slide rule is not meant to be used for measuring length or drawing straight lines. Nor is it designed for addition or subtraction, which is usually performed using other methods, like using an abacus. Maximum accuracy for standard linear slide rules is about three decimal significant digits, while scientific notation is used to keep track of the order of magnitude of results.

English mathematician and clergyman Reverend William Oughtred and others developed the slide rule in the 17th century based on the emerging work on logarithms by John Napier. It made calculations faster and less error-prone than evaluating on paper. Before the advent of the scientific pocket calculator, it was the most commonly used calculation tool in science and engineering. The slide rule's ease of use, ready availability, and low cost caused its use to continue to grow through the 1950s and 1960s, even as desktop electronic computers were gradually introduced. But after the handheld scientific calculator was introduced in 1972 and became inexpensive in the mid-1970s, slide rules became largely obsolete, so most suppliers departed the business.

In the United States, the slide rule is colloquially called a slipstick.

🔗 Microtome

🔗 Biology 🔗 Neuroscience 🔗 Physiology 🔗 Science

A microtome (from the Greek mikros, meaning "small", and temnein, meaning "to cut") is a cutting tool used to produce extremely thin slices of material known as sections, with the process being termed microsectioning. Important in science, microtomes are used in microscopy for the preparation of samples for observation under transmitted light or electron radiation.

Microtomes use steel, glass or diamond blades depending upon the specimen being sliced and the desired thickness of the sections being cut. Steel blades are used to prepare histological sections of animal or plant tissues for light microscopy. Glass knives are used to slice sections for light microscopy and to slice very thin sections for electron microscopy. Industrial grade diamond knives are used to slice hard materials such as bone, teeth and tough plant matter for both light microscopy and for electron microscopy. Gem-quality diamond knives are also used for slicing thin sections for electron microscopy.

Microtomy is a method for the preparation of thin sections for materials such as bones, minerals and teeth, and an alternative to electropolishing and ion milling. Microtome sections can be made thin enough to section a human hair across its breadth, with section thickness between 50 nm and 100 μm.

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🔗 Lady Tasting Tea

🔗 Mathematics 🔗 Statistics

In the design of experiments in statistics, the lady tasting tea is a randomized experiment devised by Ronald Fisher and reported in his book The Design of Experiments (1935). The experiment is the original exposition of Fisher's notion of a null hypothesis, which is "never proved or established, but is possibly disproved, in the course of experimentation".

The example is loosely based on an event in Fisher's life. The woman in question, phycologist Muriel Bristol, claimed to be able to tell whether the tea or the milk was added first to a cup. Her future husband, William Roach, suggested that Fisher give her eight cups, four of each variety, in random order. One could then ask what the probability was for her getting the specific number of cups she identified correct (in fact all eight), but just by chance.

Fisher's description is less than 10 pages in length and is notable for its simplicity and completeness regarding terminology, calculations and design of the experiment. The test used was Fisher's exact test.

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🔗 Sokoban

🔗 Video games

Sokoban (倉庫番, Sōko-ban, lit.'warehouse keeper') is a puzzle video game in which the player pushes boxes around in a warehouse, trying to get them to storage locations. The game was designed in 1981 by Hiroyuki Imabayashi, and first released in December 1982 for the PC-80, PC-88, and FM-7 computers.

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