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Tessellation

Tessellation
Ceramic Tiles in Marrakech, forming edge-to-edge, regular and other tessellations A periodic tiling has a repeating pattern. Some special kinds include regular tilings with regular polygonal tiles all of the same shape, and semi-regular tilings with regular tiles of more than one shape and with every corner identically arranged. History[edit] A temple mosaic from the ancient Sumerian city of Uruk IV (3400–3100 BC) showing a tessellation pattern in the tile colours. Tessellations were used by the Sumerians (about 4000 BC) in building wall decorations formed by patterns of clay tiles.[1] Etymology[edit] Overview[edit] Many other types of tessellation are possible under different constraints. Mathematically, tessellations can be extended to spaces other than the Euclidean plane.[12] The Swiss geometer Ludwig Schläfli pioneered this by defining polyschemes, which mathematicians nowadays call polytopes; these are the analogues to polygons and polyhedra in spaces with more dimensions. In art[edit] Related:  nhibui1908

Insectivore Organism which eats insects An insectivore is a carnivorous plant or animal that eats insects.[1] An alternative term is entomophage,[2] which also refers to the human practice of eating insects. The first vertebrate insectivores were amphibians. Although individually small, insects exist in enormous numbers. Examples[edit] Examples of insectivores include different kinds of species of carp, opossum, frogs, lizards (e.g. chameleons, geckos), nightingales, swallows, echidnas,[6] numbats, anteaters, armadillos, aardvarks, pangolins, aardwolfs,[7] bats, and spiders. Insectivorous plants[edit] Insectivorous plants are plants that derive some of their nutrients from trapping and consuming animals or protozoan. Insectivorous plants might consume insects and other animal material trapped adventitiously, though most species to which such food represents an important part of their intake are specifically, often spectacularly, adapted to attract and secure adequate supplies. See also[edit]

Pharyngeal jaw The pharyngeal jaws of the moray eel Pharyngeal jaws are a "second set" of jaws contained within an animal's throat, or pharynx, distinct from the primary or oral jaws. They are believed to have originated as modified gill arches, in much the same way as oral jaws. Cichlids[edit] Moray eels[edit] Most fish species with pharyngeal teeth do not have extendable pharyngeal jaws. Popular culture[edit] References[edit] External links[edit] Moscow–Washington hotline Direct communication system between Russia and the United States The Kremlin in Moscow, Russia (left) and the Pentagon in Arlington County, Virginia, U.S. (right), the two facilities linked by the hotline. The Moscow–Washington hotline (formally known in the United States as the Washington–Moscow Direct Communications Link;[1] Russian: Горячая линия Вашингтон — Москва, tr. Origins[edit] Background[edit] The 1962 Cuban Missile Crisis made the hotline a priority. During the crisis, the United States took nearly twelve hours to receive and decode Nikita Khrushchev's 3,000-word initial settlement message – a dangerously long time. Agreement[edit] The "hotline", as it would come to be known, was established after the signing of a "Memorandum of Understanding Regarding the Establishment of a Direct Communications Line" on June 20, 1963, in Geneva, Switzerland, by representatives of the Soviet Union and the United States.[3] Technical details: United States[edit] The hotline was tested hourly.

Vaporetto Vaporetto on the Canal Grande in Venice. Venice Vaporetto water bus system – water bus and bus stop The vaporetto is a Venetian public waterbus. There are 19 scheduled lines[1] that serve locales within Venice, and travel between Venice and nearby islands, such as Murano, Burano, and Lido. The name, vaporetto, could be translated as "little steamer", and refers to similarly purposed ships in the past that were run by steam. The natives call the vaporetto batèlo or vaporino. Three vaporetti carrying passengers ACTV sells 12-, 24-, 36-, 48- and 72-hour passes as well as single-journey tickets and 7-day passes.[3] The private express company Alilaguna also operates a limited water bus service, to the airport for example, although its boats (including a new one that is a hybrid electric/diesel) are not technically considered to be vaporetti.[4] The first vaporetto appeared in 1881, in competition with gondoliers and hotel boatmen. Notes[edit] External links[edit]

Dewey Decimal Classification Library classification system A library book shelf in Hong Kong classified using the New Classification Scheme for Chinese Libraries, an adaptation of the Dewey Classification Scheme The Dewey Decimal Classification (DDC), colloquially the Dewey Decimal System, is a proprietary library classification system first published in the United States by Melvil Dewey in 1876.[1] Originally described in a four-page pamphlet, it has been expanded to multiple volumes and revised through 23 major editions, the latest printed in 2011. It is also available in an abridged version suitable for smaller libraries. OCLC, a non-profit cooperative that serves libraries, currently maintains the system and licenses online access to WebDewey, a continuously updated version for catalogers. The Decimal Classification introduced the concepts of relative location and relative index which allow new books to be added to a library in their appropriate location based on subject. History[edit] Design[edit] 510 Mathematics

Cheat sheet A cheat sheet (also cheatsheet) or crib sheet is a concise set of notes used for quick reference. A cheat sheet is a physical piece of paper, often filled with equations and/or facts in compressed writing. Students often print cheat sheets in extremely small font, fitting an entire page of notes in the palm of their hands during the exam. Crib sheets are also fully worked solutions for exams or work sheets normally handed out to university staff in order to ease marking (grading). As reference cards[edit] In more general usage, a crib sheet is any short (one- or two-page) reference to terms, commands, or symbols where the user is expected to understand the use of such terms but not necessarily to have memorized all of them. Some academic and technical publishers also publish crib sheets for software packages and technical topics. See also[edit] References[edit] External links[edit] The dictionary definition of cheat sheet at Wiktionary

Sharkcano: Exploring The Relationship Between Underwater Volcanoes And Sharks Back in 2015, a video of hammerheads and silky sharks swimming around in an underwater volcano, in sizzling water temperatures and elevated acidity levels, went viral. Dubbed “sharkcano,” people wondered if there were any places sharks couldn’t survive. (Spoiler alert: there are a few, like Mount Everest and your backyard pool.) The sharks (and a sixgill stingray!) were first found inside the volcano caldera by Brennan Phillips five years ago following the eruption of submarine volcano Kavachi, which has built itself above sea level at least nine times since 1950. Located in the Solomon Islands (south of Gatokae and Vangunu islands), it is known as one of the most active underwater volcanoes in the Pacific Ocean even though it has rarely been observed. More than 70 percent of all volcanic eruptions occur underwater but researchers know very little when it comes to understanding underwater volcano behavior.

What is stream sniping? Here's what you need to know about the livestream exploitation tactic in gaming, and how to prevent it Outside broadcasting Remote production of television or radio programmes Presenters and camera operator of Sky Sports F1 on an outside broadcast in 2014 Outside broadcasting (OB) is the electronic field production (EFP) of television or radio programmes (typically to cover television news and sports television events) from a mobile remote broadcast television studio. Professional video camera and microphone signals come into the production truck for processing, recording and possibly transmission. Some outside broadcasts use a mobile production control room (PCR) inside a production truck. History[edit] Outside radio broadcasts have been taking place since the early 1920s[1] and television ones since the late 1920s.[2] The first large-scale outside broadcast was the televising of the Coronation of George VI and Elizabeth in May 1937, done by the BBC's first Outside Broadcast truck, MCR 1 (short for Mobile Control Room).[3] In December 1963 instant replays were used for the first time. New technology[edit]

Press pass A press pass (alternatively referred to as a press card or a journalist pass) grants some type of special privilege to journalists. Some cards have recognized legal status; others merely indicate that the bearer is a practicing journalist. The nature of the benefits is determined by the type of issuing agency, of which there are three major categories: news organizations, law-enforcement agencies, and event organizers (usually for a specific single affair like a corporate press conference). Each type of card grants different authorizations, thus it is often necessary or desirable for reporters to hold multiple press passes simultaneously.[1] Law-enforcement cards[edit] Police-issued passes do not grant access to government press conferences or any other such privileges: they are only recognized by emergency response personnel, and only valid within the jurisdiction of the issuing agencies.[2] Parking permits[edit] Event-specific[edit] Open events[edit] Closed events[edit] Fake cards[edit]

Garment bag Some models of garment bags may have a strap for holding them on the shoulder and quite often, some type of handle. They come in different shapes and sizes depending on the length of the clothes that should contain (jackets, coats, dresses, etc...). There is a type of garment bag , with two handles, that can be folded by the middle for easy carrying it with one hand. Garment bags protect clothing from dust, dirt and smells. They help to keep clothes in good condition whether traveling or hanging in wardrobe. Dangers[edit] Garment bags made of thin plastic are a risk to children who might play with them due to risk of death by asphyxiation.[2] See also[edit] References[edit] Digital hoarding Excessive acquisition of digital material Cluttered computer desktop, a common example of digital hoarding. Digital hoarding (also known as e-hoarding, datahording or cyberhoarding) is excessive acquisition and reluctance to delete electronic material no longer valuable to the user.[1] The behavior includes the mass storage of digital artifacts and the retention of unnecessary or irrelevant electronic data. The term is increasingly common in pop culture, used to describe the habitual characteristics of compulsive hoarding, but in cyberspace. As with physical space in which excess items are described as "clutter" or "junk", excess digital media is often referred to as "digital clutter".[2][3][4] As a medical condition[edit] Related concepts[edit] Digital clutter is the term often used to describe the resulting (digital) artifacts of digital hoarding, but it should not be understood as exclusively the result of hoarding. Virtual spaces[edit] Causes[edit] Repercussions[edit] In the media[edit]

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