Lookahead (other)
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Lookahead (other)
Lookahead or Look Ahead may refer to: * A parameter of some combinatorial search algorithms, describing how deeply the graph representing the problem is explored * A parameter of some parsing algorithms; the maximum number of tokens that a parser can use to decide which rule to use * In dynamic range compression, a signal processing design to avoid compromise between slow attack rates that produce smooth-sounding gain changes, and fast attack rates capable of catching transients * Look-ahead (backtracking), a subprocedure that attempts to predict the effects of choosing a branching variable to evaluate or one of its values * Lookahead carry unit, a logical unit in digital circuit design used to decrease calculation time in adder units * Look Ahead, a charitable housing association in London * In regular expressions, an assertion to match characters after the current position Education *''Look Ahead'', 1990s English as a foreign language multimedia classroom project by BBC Engli ...
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Combinatorial Search
{{one source , date=May 2024 In computer science and artificial intelligence, combinatorial search studies search algorithms for solving instances of problems that are believed to be hard in general, by efficiently exploring the usually large solution space of these instances. Combinatorial search algorithms achieve this efficiency by reducing the effective size of the search space or employing heuristics. Some algorithms are guaranteed to find the optimal solution, while others may only return the best solution found in the part of the state space that was explored. Classic combinatorial search problems include solving the eight queens puzzle or evaluating moves in games with a large game tree, such as reversi or chess. A study of computational complexity theory helps to motivate combinatorial search. Combinatorial search algorithms are typically concerned with problems that are NP-hard. Such problems are not believed to be efficiently solvable in general. However, the various ...
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Parsing
Parsing, syntax analysis, or syntactic analysis is a process of analyzing a String (computer science), string of Symbol (formal), symbols, either in natural language, computer languages or data structures, conforming to the rules of a formal grammar by breaking it into parts. The term ''parsing'' comes from Latin ''pars'' (''orationis''), meaning Part of speech, part (of speech). The term has slightly different meanings in different branches of linguistics and computer science. Traditional Sentence (linguistics), sentence parsing is often performed as a method of understanding the exact meaning of a sentence or word, sometimes with the aid of devices such as sentence diagrams. It usually emphasizes the importance of grammatical divisions such as subject (grammar), subject and predicate (grammar), predicate. Within computational linguistics the term is used to refer to the formal analysis by a computer of a sentence or other string of words into its constituents, resulting in a par ...
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Dynamic Range Compression
Dynamic range compression (DRC) or simply compression is an audio signal processing operation that reduces the volume of loud sounds or amplifies quiet sounds, thus reducing or ''compressing'' an audio signal's dynamic range. Compression is commonly used in sound recording and reproduction, broadcasting, sound reinforcement system, live sound reinforcement and some instrument amplifiers. A dedicated electronic hardware unit or audio software that applies compression is called a compressor. In the 2000s, compressors became available as software plugins that run in digital audio workstation software. In recorded and live music, compression parameters may be adjusted to change the way they affect sounds. Compression and limiting are identical in process but different in degree and perceived effect. A limiter is a compressor with a high #Ratio, ratio and, generally, a short #Attack and release, attack time. Compression is used to improve performance and clarity in public address ...
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Look-ahead (backtracking)
In backtracking algorithms, look ahead is the generic term for a subprocedure that attempts to foresee the effects of choosing a branching variable to evaluate one of its values. The two main aims of look-ahead are to choose a variable to evaluate next and to choose the order of values to assign to it. Constraint satisfaction In a general constraint satisfaction problem, every variable can take a value in a domain. A backtracking algorithm therefore iteratively chooses a variable and tests each of its possible values; for each value the algorithm is recursively run. Look ahead is used to check the effects of choosing a given variable to evaluate or to decide the order of values to give to it. Look ahead techniques The simpler technique for evaluating the effect of a specific assignment to a variable is called forward checking. Given the current partial solution and a candidate assignment to evaluate, it checks whether another variable can take a consistent value. In other word ...
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Lookahead Carry Unit
A lookahead carry unit (LCU) is a logical unit in digital circuit In theoretical computer science, a circuit is a model of computation in which input values proceed through a sequence of gates, each of which computes a function. Circuits of this kind provide a generalization of Boolean circuits and a mathematica ... design used to decrease calculation time in adder units and used in conjunction with carry look-ahead adders (CLAs). 4-bit adder A single 4-bit CLA is shown below: 16-bit adder By combining four 4-bit CLAs, a 16-bit adder can be created but additional logic is needed in the form of an LCU. The LCU accepts the group propagate (P_G) and group generate (G_G) from each of the four CLAs. P_G and G_G have the following expressions for each CLA adder: :P_G = P_0 \cdot P_1 \cdot P_2 \cdot P_3 :G_G = G_3 + G_2 \cdot P_3 + G_1 \cdot P_2 \cdot P_3 + G_0 \cdot P_1 \cdot P_2 \cdot P_3 The LCU then generates the carry input for each CLA. Assume that P_i is P_G and G_i is G_G ...
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Look Ahead
Look Ahead is a charitable housing association based in East London which was established in 1973. It was involved in the Rough Sleepers Initiative in the 1990s and originally ran a number of large hostels. The last big hostel closed in 2012 and it now provides smaller more specialist services. In 2017 it had more than 1000 staff and was supporting more than 6500 people with mental health problems, learning disabilities, homelessness and young care leavers. It runs the Tabard Forensic Service, in Tower Hamlets, in partnership with East London NHS Foundation Trust and the London Borough of Tower Hamlets The London Borough of Tower Hamlets is a London boroughs, borough in London, England. Situated on the north bank of the River Thames and immediately east of the City of London, the borough spans much of the traditional East End of London and ..., which provides residential step down support for secure forensic patients. Look Ahead invested £500,000 to refurbish and adapt ...
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Regular Expression
A regular expression (shortened as regex or regexp), sometimes referred to as rational expression, is a sequence of characters that specifies a match pattern in text. Usually such patterns are used by string-searching algorithms for "find" or "find and replace" operations on strings, or for input validation. Regular expression techniques are developed in theoretical computer science and formal language theory. The concept of regular expressions began in the 1950s, when the American mathematician Stephen Cole Kleene formalized the concept of a regular language. They came into common use with Unix text-processing utilities. Different syntaxes for writing regular expressions have existed since the 1980s, one being the POSIX standard and another, widely used, being the Perl syntax. Regular expressions are used in search engines, in search and replace dialogs of word processors and text editors, in text processing utilities such as sed and AWK, and in lexical analysis ...
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Perl Compatible Regular Expressions
Perl Compatible Regular Expressions (PCRE) is a library written in C, which implements a regular expression engine, inspired by the capabilities of the Perl programming language. Philip Hazel started writing PCRE in summer 1997. PCRE's syntax is much more powerful and flexible than either of the POSIX regular expression flavors (BRE, ERE) and than that of many other regular-expression libraries. While PCRE originally aimed at feature-equivalence with Perl, the two implementations are not fully equivalent. During the PCRE 7.x and Perl 5.9.x phase, the two projects coordinated development, with features being ported between them in both directions. In 2015, a fork of PCRE was released with a revised programming interface (API). The original software, now called PCRE1 (the 1.xx–8.xx series), has had bugs mended, but no further development. , it is considered obsolete, and the current 8.45 release is likely to be the last. The new PCRE2 code (the 10.xx series) has had a number ...
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English As A Foreign Language
English as a second or foreign language refers to the use of English by individuals whose native language is different, commonly among students learning to speak and write English. Variably known as English as a foreign language (EFL), English as a second language (ESL), English for speakers of other languages (ESOL), English as an additional language (EAL), or English as a new language (ENL), these terms denote the study of English in environments where it is not the dominant language. Programs such as ESL are designed as academic courses to instruct non-native speakers in English proficiency, encompassing both learning in English-speaking nations and abroad. Teaching methodologies include teaching English as a foreign language (TEFL) in non-English-speaking countries, teaching English as a second language (TESL) in English-speaking nations, and teaching English to speakers of other languages (TESOL) worldwide. These terms, while distinct in scope, are often used interchan ...
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Look Ahead (Pat Boone Album)
''Look Ahead'' is the 38th studio album by Pat Boone, released in 1968 on Dot Records. It became his last album for the label. The album mainly contains covers of country and western A country is a distinct part of the world, such as a state, nation, or other political entity. When referring to a specific polity, the term "country" may refer to a sovereign state, state with limited recognition, constituent country, or d ... songs of the time. Track listing References {{Authority control 1968 albums Pat Boone albums Dot Records albums ...
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Gerald Veasley
Gerald Veasley (born July 28, 1955) is an American jazz bass guitarist. Veasley was born and raised in West Philadelphia, where he played in R&B groups as a teenager. He received a bass guitar for Christmas from his dad when he was 12 years old and his relatives drove him to music lessons. A strong student, Veasley was attending University of Pennsylvania with plans to go to get a Juris Doctor degree, but then his father died. After that, Veasley changed directions following his heart which was to pursue music. His uncle Ira Tucker, lead singer of the gospel quartet The Dixie Hummingbirds, took him under his wing providing him work at the beginning of his career. Veasley also worked in an R&B revue-carnival run by his cousin and his cousin's wife, and from this experience learned what it would be like to be a musician. In the early 80's Grover Washington Jr. asked Veasley to work with him. He then connected with Joe Zawinul from 1988 to 1995, and began releasing his own reco ...
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Danny Tenaglia
Daniel "Danny" Tenaglia (born March 7, 1961) is an Italian American DJ and record producer. Biography Early life Tenaglia left New York in 1985 and started DJing in Miami as a resident at Cheers nightclub, playing classic New York and Chicago house. He returned to New York five years later. At this time, he started to create some remixes, including Right Said Fred's " I'm Too Sexy" (1991), Jamiroquai's " Emergency on Planet Earth" (1993), and Madonna's "Human Nature" (1994). DJ career Tenaglia's first mainstream success was with a remix of the Daou's "Surrender Yourself" (1993). Subsequent to this Tenaglia released three label compilations - ''Mix This Pussy'' (1994) and ''Can Your Pussy Do the Dog?'' (1995) for TRIBAL, and ''Gag Me with a Tune'' (1996) for Maxi. As a producer In 1996, after working for a short time at the New York nightclub Roxy, Tenaglia started a Saturday night residency at Twilo. In 1998, he moved his residency over to NY club Tunnel. In 1998, Tenagli ...
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