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Information theory

Information theory
Overview[edit] The main concepts of information theory can be grasped by considering the most widespread means of human communication: language. Two important aspects of a concise language are as follows: First, the most common words (e.g., "a", "the", "I") should be shorter than less common words (e.g., "roundabout", "generation", "mediocre"), so that sentences will not be too long. Such a tradeoff in word length is analogous to data compression and is the essential aspect of source coding. Second, if part of a sentence is unheard or misheard due to noise — e.g., a passing car — the listener should still be able to glean the meaning of the underlying message. Note that these concerns have nothing to do with the importance of messages. Information theory is generally considered to have been founded in 1948 by Claude Shannon in his seminal work, "A Mathematical Theory of Communication". Historical background[edit] With it came the ideas of Quantities of information[edit] Entropy[edit] . that Related:  i have questions and needs

The Traditional Four-Step Method | Bean Institute Dry beans are an incredibly nutritious, versatile and inexpensive ingredient. The cost of one ½ cup serving of dry beans is about one-third the cost of canned beans. Cooking with dry beans is easy and rewarding, but to cook with dry beans versus canned beans you need to follow four simple steps. For best results, follow these tips! Keep cooking water at a gentle simmer to prevent split skins.Since beans expand as they cook, add warm water periodically during the cooking process to keep the beans covered.Stir beans occasionally throughout the cooking process to prevent sticking.You can “bite test” beans for tenderness.

Cybernetics Cybernetics is a transdisciplinary[1] approach for exploring regulatory systems, their structures, constraints, and possibilities. Cybernetics is relevant to the study of systems, such as mechanical, physical, biological, cognitive, and social systems. Cybernetics is applicable when a system being analyzed incorporates a closed signaling loop; that is, where action by the system generates some change in its environment and that change is reflected in that system in some manner (feedback) that triggers a system change, originally referred to as a "circular causal" relationship. Concepts studied by cyberneticists (or, as some prefer, cyberneticians) include, but are not limited to: learning, cognition, adaptation, social control, emergence, communication, efficiency, efficacy, and connectivity. Norbert Wiener defined cybernetics in 1948 as "the scientific study of control and communication in the animal and the machine Definitions[edit] Other notable definitions include: Etymology[edit] W.

Doron Swade - Computing History Doron Swade An academic who masterminded an 18-year project to recreate a 19th Century computer, a dedicated nurse and an 84-year old volunteer are among Kingstonians rewarded in the UK 2009 New Year's Honours List. Dr Doron Swade, 64, is a leading academic in computer history and a world renowned expert on the work of English mathematician Charles Babbage and has been awarded an MBE for services to the history of computing. Dr Swade, a former curator at the London Science Museum, said: “I am hugely flattered and very, very grateful. “I've always said honours and acknowledgements are the result of good work and I just try to do good work.” Dr Swade masterminded a project to build a working replica of one of Babbage’s ‘calculating engines’ from the original 19th century plans and negotiated the acquisition of rare computers including a Russian Cold War supercomputer and the last working totalisator in the country for the National Computer Collection. Dr. Doron has curated many exhibitions.

Harlan County War The Harlan County War, or Bloody Harlan, was a series of coal mining-related skirmishes, executions, bombings, and strikes (both attempted and realized) that took place in Harlan County, Kentucky during the 1930s. The incidents involved coal miners and union organizers on one side, and coal firms and law enforcement officials on the other.[1] The question at hand: the rights of Harlan County coal miners to organize their workplaces and better their wages and working conditions. It was a nearly decade-long conflict, lasting from 1931 to 1939. Before its conclusion, an indeterminate number of miners, deputies, and bosses would be killed, state and federal troops would occupy the county more than half a dozen times, two acclaimed folk singers would emerge, union membership would oscillate wildly, and workers in the nation's most anti-labor coal county would ultimately be represented by a union. History[edit] "Sheriff J.H. Impact[edit] See also[edit] References[edit] External links[edit]

Decision theory Normative and descriptive decision theory[edit] Since people usually do not behave in ways consistent with axiomatic rules, often their own, leading to violations of optimality, there is a related area of study, called a positive or descriptive discipline, attempting to describe what people will actually do. Since the normative, optimal decision often creates hypotheses for testing against actual behaviour, the two fields are closely linked. Furthermore it is possible to relax the assumptions of perfect information, rationality and so forth in various ways, and produce a series of different prescriptions or predictions about behaviour, allowing for further tests of the kind of decision-making that occurs in practice. In recent decades, there has been increasing interest in what is sometimes called 'behavioral decision theory' and this has contributed to a re-evaluation of what rational decision-making requires.[1] What kinds of decisions need a theory? Choice under uncertainty[edit]

The sounds of English and the International Phonetic Alphabet © Tomasz P. Szynalski, Antimoon.com This chart contains all the sounds (phonemes) used in the English language. For each sound, it gives: The symbol from the International Phonetic Alphabet (IPA), as used in phonetic transcriptions in modern dictionaries for English learners — that is, in A. To print the chart, use the printable PDF version. Does this chart list all the sounds that you can hear in British and American English? No. For example, this page does not list the regular t (heard in this pronunciation of letter) and the flap t (heard in this one) with separate symbols. So this page actually lists phonemes (groups of sounds), not individual sounds. Take the phoneme p in the above chart. Typing the phonetic symbols You won’t find phonetic symbols on your computer’s keyboard. You can use my free IPA phonetic keyboard at ipa.typeit.org. You can also use the ASCII Phonetic Alphabet, which represents IPA symbols with “normal” characters that you can type on your keyboard.

Castor and Pollux Castor[a] and Pollux[b] (or in Greek, Polydeuces[c]) were twin half-brothers in Greek and Roman mythology, known together as the Dioscuri.[d] Birth and functions[edit] Castor depicted on a calyx krater of c. 460–450 BC, holding a horse's reins and spears and wearing a pilos-style helmet Castor and Pollux are sometimes both mortal, sometimes both divine. One consistent point is that if only one of them is immortal, it is Pollux. The Dioscuri were regarded as helpers of humankind and held to be patrons of travellers and of sailors in particular, who invoked them to seek favourable winds.[3] Their role as horsemen and boxers also led to them being regarded as the patrons of athletes and athletic contests.[4] They characteristically intervened at the moment of crisis, aiding those who honoured or trusted them.[5] Classical sources[edit] Pair of Roman statuettes (3rd century AD) depicting the Dioscuri as horsemen, with their characteristic skullcaps (Metropolitan Museum of Art) Mythology[edit]

Cray-1 Cray-1 with internals exposed at EPFL The Cray-1 was a supercomputer designed, manufactured and marketed by Cray Research. The first Cray-1 system was installed at Los Alamos National Laboratory in 1976 and it went on to become one of the best known and most successful supercomputers in history. History[edit] Jim Thornton, formerly Cray's engineering partner on earlier designs, had started a more radical project known as the CDC STAR-100. As a result, Cray left CDC and started a new company HQ only yards from the CDC lab. In 1975 the 80 MHz Cray-1 was announced. The 80 MFLOPS Cray-1 was succeeded in 1982 by the 800 MFLOPS Cray X-MP, the first Cray multi-processing computer. Background[edit] Typical scientific workloads consist of reading in large data sets, transforming them in some way and then writing them back out again. Vector machines[edit] In the STAR, new instructions essentially wrote the loops for the user. The real savings are not so obvious. Cray's approach[edit] Cray-1S[edit]

Theory of everything A theory of everything (ToE) or final theory, ultimate theory, or master theory is a hypothetical single, all-encompassing, coherent theoretical framework of physics that fully explains and links together all physical aspects of the universe.[1]:6 Finding a ToE is one of the major unsolved problems in physics. Over the past few centuries, two theoretical frameworks have been developed that, as a whole, most closely resemble a ToE. The two theories upon which all modern physics rests are general relativity (GR) and quantum field theory (QFT). GR is a theoretical framework that only focuses on the force of gravity for understanding the universe in regions of both large-scale and high-mass: stars, galaxies, clusters of galaxies, etc. Through years of research, physicists have experimentally confirmed with tremendous accuracy virtually every prediction made by these two theories when in their appropriate domains of applicability. Historical antecedents[edit] Modern physics[edit] [edit]

Single Convention on Narcotic Drugs 1961 international treaty regulating narcotic drugs The Single Convention on Narcotic Drugs, 1961 (Single Convention, 1961 Convention, or C61) is an international treaty that controls activities (cultivation, production, supply, trade, transport) of specific narcotic drugs and lays down a system of regulations (licenses, measures for treatment, research, etc.) for their medical and scientific uses; it also establishes the International Narcotics Control Board. The Single Convention was adopted in 1961[1] and amended in 1972.[2] As of 2022, the Single Convention as amended has been ratified by 186 countries.[3] The convention has since been supplemented by the 1971 Convention on Psychotropic Substances, which controls LSD, MDMA, and other psychoactive pharmaceuticals, and the 1988 United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances. Ratification[edit] History[edit] Provisions[edit] Purposes[edit] Medical and scientific purposes[edit] Schedules[edit]

Codognet states, "Information theory can be thought of as a sort of simplified or idealized semiotics: a ciphering/deciphering algorithm represents the interpretation process used to decode some signifier (encoded information) into some computable signified (meaningful information) to be fed to a subsequent processing step. This process, like semiosis itself, is, of course unlimted." by arlene Mar 24

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