Cleanup date July 2009 The pumpinglemma for contextfreelanguages , also known as the Yehoshua Bar Hillel Bar Hillel lemma , is a lemma mathematics lemma that gives a property shared by all contextfree language s. Formal statement If a language L is contextfree, then there exists some integer p 1 ... integer n 0. Informal statement and explanation The pumpinglemma for contextfreelanguages called just the pumpinglemma from now on describes a property that all contextfreelanguages are guaranteed ... 94728 X Section 1.4 Nonregular Languages, pp. 77&ndash 83. Section 2.3 Non contextfreeLanguages, pp. 115&ndash 119. DEFAULTSORT PumpingLemma For ContextFreeLanguages Category Formal languages ... p , where p is a constant called the pumping length that varies between contextfreelanguages. Say s is a string of length at least p that is in the language. The pumpinglemma states that s can be split ... the string . This process of pumping up additional copies of v and y is what gives the pumpinglemma its name. Note that finite language s which are regular and hence contextfree obey the pumpinglemma ... the pumpinglemma in a proof by contradiction . First, assume that math L math is contextfree. By the pumping ... freelanguages. See also Pumpinglemma for regular languages Formal languages References cite journal ... for contextfreelanguages can be used to show that certain languages are not contextfree. For example ... free must be false. While the pumpinglemma is often a useful tool to prove that a given language is not contextfree, it does not give a complete characterization of the contextfreelanguages. If a language does not satisfy the condition given by the pumpinglemma, we have established that it is not contextfree. On the other hand, there are languages that are not contextfree, but still satisfy ... of this length the pumpinglemma is not violated. The pumpinglemma is often used to prove that a given language is non contextfree by showing that for each p , we can find some string s of length at least ... more details
Pumpinglemma for contextfreelanguages Formal languages Ogden s lemma Notes references References ...In the theory of formal language s, the pumpingLemma mathematics lemma for regular languages describes ... and explanation The pumpinglemma describes an essential property of regular languages. It says that for any ... a string that is still in L . This process of repetition is known as pumping . Moreover, the pumpinglemma guarantees that the length of xy will be at most p , imposing a limit on the ways in which w may be split. Note that finite languages satisfy the pumpinglemma trivially by having p equal to the maximum string length in L plus one. Use of lemma The pumpinglemma is often used to prove that a particular ... version of pumpinglemma for regular languages If a language L is regular, then there exists ... number of times to produce a new word which also lies within the same language. The pumpinglemma .... It is one of a few pumpinglemma s, each with a similar purpose. Formal statement Let L be a regular ... is a formal expression of the PumpingLemma. math begin array l forall L subseteq Sigma quad mbox regular ... in the pumpinglemma. For example the language L a sup n sup b sup n sup n &ge 0 over the alphabet &Sigma a , b can be shown to be non regular as follows. Let w , x , y , z , p , and i be as used in the Pumpinglemma for regular languages Formal statement formal statement for the pumpinglemma above. Let w in L be given by w a sup p sup b sup p sup . By the pumpinglemma, there must be some decomposition ... parentheses, and so they cannot be balanced. Proof of the pumpinglemma For every regular language ... that neither the original nor the general version of the pumpinglemma give a Necessary and sufficient ... regular languages. If the lemma does not hold for a language L , then L is not regular. If the lemma ... Category Lemmas de PumpingLemma Regul re Sprachen hr Svojstvo napuhavanja za regularne jezike it Pumping ... at least p p is called the pumping length can be written as w xyz i.e., w can be divided into three ... more details
In the theory of formal language s in computability theory , a pumpinglemma or pumping argument states that, for a particular language to be a member of a language class, any sufficiently long string in the language contains a section, or sections, that can be removed, or repeated any number of times, with the resulting string remaining in that language. The proofs of these lemmas typically require counting argument s such as the pigeonhole principle . The two most important examples are the pumpinglemma for regular languages and the pumpinglemma for contextfreelanguages . Ogden s lemma is a second, stronger pumpinglemma for contextfree language s. These lemma mathematics lemma s can be used to determine if a particular language is not in a given language class. However, they cannot be used to determine if a language is in a given class, since satisfying the pumpinglemma is a necessary and sufficient necessary , but not sufficient, condition for class membership. References cite book author Michael Sipser year 1997 title Introduction to the Theory of Computation publisher PWS Publishing isbn 0 534 94728 X Section 1.4 Nonregular Languages, pp. 77&ndash 83. Section 2.3 Non contextfreeLanguages, pp. 115&ndash 119. cite book author Thomas A. Sudkamp year 2006 title Languages and Machines, Third edition publisher Adison Wesley isbn 0 321 32221 5 Chapter 6 Properties of Regular Languages pp. 205 210 Category Formal languages Category Lemmas bs Osobina napuhavanja cs Lemma o vkl d n de PumpingLemma es Lema del bombeo fr Lemme de l toile ko hr Svojstvo napuhavanja it Pumpinglemma nl Pompstelling ja pt Lema do bombeamento ro Lema de pompare ru sr uk zh ... more details
Contextfree may refer to Concepts contextfree grammar deterministic contextfree grammar stochastic contextfree grammar weighted contextfree grammar contextfree language Software ContextFree , a computer language for contextfree grammars disambig ... more details
is not contextfree, one may employ the pumpinglemma for contextfreelanguages . References cite book author Seymour Ginsburg title The Mathematical Theory of ContextFreeLanguages year 1966 publisher ... B a m b n c n mid m,n geq 0 math , which are both contextfree. Their intersection is math A cap B a n b n c n mid n geq 0 math , which can be shown to be non contextfree by the pumpinglemma for contextfreelanguages . Contextfreelanguages are also not closed under complementation, as for any ... symbol and math x math means pop action. center Contextfreelanguages have many applications in programming ... by contextfree grammars. Closure properties Contextfreelanguages are closure mathematics closed under the following operations. That is, if L and P are contextfreelanguages, the following languages are contextfree as well the union set theory union math L cup P math of L and P the reversal of L ... of L the language math vu uv in L math Contextfreelanguages are not closed under complement complexity ... difference . However, if L is a contextfree language and D is a regular language then both their intersection math L cap D math and their difference math L setminus D math are contextfreelanguages. Nonclosure under intersection and complement The contextfreelanguages are not closed under ... problems are decidable for arbitrary contextfreelanguages is math L A emptyset math ... of contextfreelanguages The reverse of a contextfree language is contextfree, but the complement ... mlv.fr berstel Articles 1997CFLPDA.pdf ContextFreeLanguages and Push Down Automata , in G. Rozenberg ...In formal language theory , a contextfree language is a formal language language generated by some contextfree grammar . The set of all contextfreelanguages is identical to the set of languages accepted by pushdown automaton pushdown automata . Examples An archetypical contextfree language is math ... The following problems are Undecidable language undecidable for arbitrary contextfree grammar s A and B ... more details
regular according to the PumpingLemma for regular languages . The special character stands ... contextfree language. However, there are certain languages that can only be generated by ambiguous grammars such languages are called inherently ambiguous. Normal forms Every contextfree grammar ... languages and contextfreelanguages year 1982 last Pullum first Geoffrey K. coauthors Gerald Gazdar ... 91 101. Section 4.1.2 Decidable problems concerning contextfreelanguages, pp. 156 159. Section ...In formal language theory , a contextfree grammar CFG is a formal grammar in which every Production ... language language s generated by contextfree grammars are known as the contextfree language s. Contextfree grammars are important in linguistics for describing the structure of sentences ... grammar to refer to contextfree grammars. In computer science , a popular notation for context ... such cases can be explained in an alternative way that doesn t assume overlap. A contextfree grammar ... of the contextfree grammar, but the basic recursive structure of sentences, the way in which ... by nouns and verbs, is described exactly. The formalism of contextfree grammars was developed ... s generative grammar framework, the syntax of natural language was described by a contextfree ... Generalized Phrase Structure Grammar Gazdar et al. 1985 , contextfree grammars were taken to be the mechanism ..., as a consequence, also featured a contextfree grammar to describe the resulting Algol syntax. This became ... language design committee. The block structure aspect that contextfree grammars capture is so fundamental to grammar that the terms syntax and grammar are often identified with contextfree grammar ... to be part of the semantics of the language. Contextfree grammars are simple enough to allow ... only with more restrictive subsets of contextfree grammars. Formal definitions A contextfree ... Rightarrow u 2 cdots Rightarrow u k Rightarrow v math Contextfree language The language of a grammar ... more details
. The deterministic contextfreelanguages are exactly those recognized by some LR grammar ref ... contextfreelanguages can be recognized by a deterministic Turing machine in polynomial ...A deterministic contextfree language is a formal language which is defined by a deterministic contextfree grammar . ref cite book last John Hopcroft Hopcroft first John coauthors Jeffrey Ullman title Introduction to automata theory, languages, and computation year 1979 publisher Addison Wesley page 233 ref The set of deterministic contextfreelanguages is called DCFL ref CZoo Class DCFL D dcfl ref and is identical to the set of languages accepted by a deterministic pushdown automaton . The set of deterministic contextfreelanguages are a proper subset of the set of contextfree language s that possess an unambiguous contextfree grammar . For example, the language of even length palindrome s on the alphabet of 0 and 1 has the simple, unambiguous grammar S 0S0 1S1 , but it cannot be parser parsed by a deterministic push down automaton. ref cite book last John Hopcroft Hopcroft first John coauthors Rajeev Motwani & Jeffrey Ullman title Introduction to automata theory, languages, and computation 2nd edition year 2001 publisher Addison Wesley pages 249 253 ref The languages of this class have practical importance in computer science. The complexity of the program and execution of a deterministic pushdown automaton is vastly less than that of a nondeterministic one. In the naive implementation ... known algorithm to test membership in any contextfree language is CYK algorithm Extensions Valiant s algorithm , taking O n sup 2.378 sup time, whereas membership in a deterministic contextfree language ... pushdown language s Greibach s theorem proves that it is undecidable whether a given contextfree language is deterministic References references Formal languages and grammars Category Formal languages ... to automata theory, languages, and computation 2nd edition year 2001 publisher Addison Wesley ... more details
In formal grammar theory, the deterministic contextfree grammars DCFGs are a proper subset of the contextfree grammars . The deterministic contextfree grammars are those a deterministic pushdown automaton can recognize. A DCFG is the finite set of rules defining the set of well formed expressions in some deterministic contextfree language . History In the 1960s, theoretic research in computer science on regular expressions and finite automata led to the discovery that contextfree grammars are equivalent to pushdown automata . These grammars were thought to capture the syntax of computer programming languages. The first computer programming languages were under development at the time see History of programming languages and writing compilers was difficult. But using contextfree grammars to help automate the parsing part of the compiler simplified the task. Deterministic contextfree grammars were particularly useful because they could be parsed sequentially, which was a requirement due to computer memory constraints. ref cite book editors A Salomaa & D Wood & S Yu title A Half Century of Automata Theory year 2001 publisher World Scientific Publishing Co. Pte. Ltd pages 38 39 ref Uses LALR parsers, which use a subset of DCFGs, have practical value as program code validators. Given the formal rules of a DCFG, these parsers efficiently ensure a program can be generated from those rules. In fact, this syntax validation is one of the operations a compiler performs. need to state the two restrictions for determinism, can t figure out how to express it simply Limitations Since DCFGs are a proper subset of CFGs, they are of less descriptive power than some CFGs. See also Deterministic parsing LR parser LL parser References references Formal languages and grammars Category Formal languages hr Deterministi ka kontekstno neovisna gramatika sr zh ... more details
A weighted contextfree grammar WCFG is a contextfree grammar where each production has a numeric weight associated with it. The weight of a parse tree in a WCFG is the weight of the rule used to produce the top node, plus the weights of its children. A special case of WCFGs are stochastic contextfree grammar s, where the weights are logarithm s of probability probabilities . An extended version of the CYK algorithm can be used to find the lightest least weight derivation of a string given some WCFG. comp sci theory stub Category Formal languages hr Te inska kontekstno neovisna gramatika ja ru ... more details
than the class of LCFRSs as a whole. References references Formal languages and grammars DEFAULTSORT Generalized ContextFree Grammar Category Formal languages Category Grammar frameworks ...Generalized Contextfree Grammar GCFG is a grammar formalism that expands on contextfree grammars by adding potentially non contextfree composition functions to rewrite rules. ref name weir1988 Weir, David H. 1988. Characterizing mildly context sensitive grammar formalisms. Dissertation, U Penn. ref Head grammar and its weak equivalents is an instance of such a GCFG which is known to be especially adept at handling a wide variety of non CF properties of natural language. Description A GCFG consists of two components a set of composition functions that combine string tuples, and a set of rewrite rules. The composition functions all have the form math f langle x 1, ..., x m rangle, langle y 1, ..., y n rangle, ... gamma math , where math gamma math is either a single string tuple, or some use of a potentially different composition function which reduces to a string tuple. Rewrite rules look like math X to f Y, Z, ... math , where math Y math , math Z math , ... are string tuples or non terminal symbols. The rewrite semantics of GCFGs is fairly straight forward. An occurrence of a non terminal symbol is rewritten using rewrite rules as in a contextfree grammar, eventually yielding just compositions composition functions applied to string tuples or other compositions . The composition functions are then applied, reducing successively reducing the tuples to a single tuple. Example A simple translation of a contextfree grammar into a GCFG can be performed in the following fashion. Given the grammar in 1 , which generates the palindrome language math ww R w in a, b math , where ... rangle, langle a rangle math math langle abbbba rangle math Linear Contextfree Rewriting Systems LCFRSs ... and regular is called a Linear Contextfree Rewriting System LCFRS , a subset of the GCFGs with strictly ... more details
Synchronous contextfree grammars SynCFG or SCFG not to be confused with Stochastic contextfree grammar stochastic CFGs constitute a formal model of natural language syntax , developed in the area of statistical machine translation MT . The theory of SynCFGs borrows from syntax directed transduction and syntax based machine translation , modeling the reordering of clauses that occurs when translating a sentence by correspondences between phrase structure rules in the source and target languages. Performance of SCFG based MT systems has been found comparable with, or even better than, state of the art phrase based machine translation systems. ref name Chiang cite journal last1 Chiang first1 David year 2007 title Hierarchical phrase based translation journal Computational Linguistics journal Computational Linguistics volume 33 number 2 pages 201 228 ref Several algorithms exist to perform translation using SynCFGs. ref cite conference last1 Venugopal first1 Ashish last2 Zollmann first2 Andreas last3 Vogel first3 Stephan year 2007 title An efficient two pass approach to Synchronous CFG driven statistical MT booktitle Proc. NAACL HLT pages 500 507 ref Formalism Rules in a SynCFG are superficially similar to CFG rules, except that they specify the structure of two phrases at the same time one in the source language the language being translated and one in the target language. Numeric indices indicate correspondences between non terminals in both constituent trees. Chiang ref name Chiang gives the Chinese English example math X to math yu math X 1 math you math X 2 math , have math X 2 math with math X 1 math Software http cdec decoder.org cdec , MT decoding package that supports SynCFGs References references Category Formal languages Category Machine translation Category Natural language parsing Category Statistical natural language processing ... more details
processing Contextfree grammars were originally conceived in an attempt to model natural languages ...Weasel date June 2010 A stochastic contextfree grammar SCFG also probabilistic contextfree grammar , PCFG is a contextfree grammar in which each production is augmented with a probability. The probability of a derivation parse is then the product of the probabilities of the productions used in that derivation thus some derivations are more consistent with the stochastic grammar than others. SCFGs extend contextfree grammars in the same way that hidden Markov model s extend regular grammar s. SCFGs have application in areas as diverse as Natural language processing to the study of RNA molecules. SCFGs are a specialized form of weighted contextfree grammar s. Techniques A variant of the CYK algorithm finds the Viterbi algorithm Viterbi parse of a sequence for a given SCFG. The Viterbi parse is the most likely derivation parse of the sequence by the given SCFG. The Inside and Outside algorithms are analogues of the Forward algorithm and Backward algorithm , and can be used to compute the total probability of all derivations that are consistent with a given sequence, based on some SCFG. This is equivalent to the probability of the SCFG generating the sequence, and is intuitively a measure of how consistent the sequence is with the given grammar. The Inside outside algorithm Inside Outside algorithms can also be used to compute the probabilities that a given production will be used ... and thereby their performance. Citation needed date June 2010 RNA Contextfree grammars are adept at modeling ... of this base pairing can be represented in a contextfree grammar the major exception being pseudoknot ... Rfam Database DEFAULTSORT Stochastic ContextFree Grammar Category Bioinformatics Category Formal languages Category Natural language parsing Category Statistical natural language processing Category ... it was claimed that grammars for natural languages governed by deterministic rules could not be learned ... more details
wiktionary pumpingPumping can refer to The operation of a pump , for moving a liquid from one location to another The use of a breast pump or milking machine for extraction of milk Gastric lavage The process of cleaning the contents of the stomach Pumping oil well , injecting chemicals into a wellbore Pumping computer systems , the number of times data is transmitted per clock cycle Pump skateboarding , a process by which longboard skateboarders accelerate without pushing off of the ground Pumpinglemma in the theory of formal languages An artifact of audio dynamic range compression Optical pumping , a process in which light is used to raise electrons from a lower energy level in an atom or molecule to a higher one Weight training pumping iron building muscle by exercising with weights Sexual intercourse Pumping My Heart , a song by Patti Smith Group See also Pump disambig es Bombeo de Pumpen ... more details
, split, etc. . DEFAULTSORT Context Category Page description languages Category Free TeX software de ... ConTeXt is free software the program code i.e. anything not under the code doc code subtree is distributed ... center 500px ConTeXt document See also Portal Free software LaTeX TeX References Reflist 2 External ...Distinguish ConTEXT Infobox software name ConTeXt logo Image ConTeXt Unofficial Logo.svg The Unofficial ConTeXt logo contextgarden.net logo 200px author Mainly Hans Hagen and http www.pragma ade.com Pragma ... of ConTeXt at contextgarden ref ref http foundry.supelec.fr frs ?group id 14 List of releases of ConTeXt ref ref http foundry.supelec.fr gf project contextrev frs ConTeXt files in Supelec ref operating ... Share Alike 3.0 ref http www.pragma ade.com general manuals mreadme.pdf Readme First license of ConTeXt code and documentation ref website http wiki.contextgarden.net contextgarden ConTeXt is a general ... and automated capabilities of ConTeXt are extensive, including interfaces for handling microtypography ... it easy to create new layouts and styles without learning the low level TeX macro language. ConTeXt .... ConTeXt from the ground up is a typography and typesetting system meant to provide users easy and consistent ... at the same time, ConTeXt s unified design avoids the package clashes that can happen with LaTeX. ref http www.tex.ac.uk cgi bin texfaq2html?label context FAQ of the UK TeX Archive ref ref name whatiscontextwiki http wiki.contextgarden.net What is ConTeXt What is ConTeXt page at contextgarden ref ConTeXt ..., and Italian and support for output in many languages including western European, eastern European ... As its native drawing engine, ConTeXt integrates a superset of MetaPost called MetaFun ref name whatiscontextwiki ... and ornaments. Metafun can also be used with stand alone MetaPost. ConTeXt also supports the use of other ... generic pgf pgfmanual.pdf PGF TikZ official manual. Version 2.0 . Section 9.1.3 Using the ConTeXt Format . p. 88 ref and PSTricks. ref name list modules http wiki.contextgarden.net Modules List of ConTeXt ... more details
are supported for searching and replacing. ConTEXT is available in many languages. On 7 September 2007 the creator of ConTEXT announced he wanted to sell the project including the full source, copyrights, website and domain. ref http www.contexteditor.org ConTEXT Freeware Text Editor Home Bot generated title ref In December 2007 it was announced that the complete project was bought and ConTEXT Project was set up as a company. In March 2009 the decision was made to make ConTEXT open source ...Infobox Software name ConTEXT logo Image ConTEXT Logo.png screenshot Image ConTEXT 0.98.3.png 250px caption ConTEXT v0.98.6 developer ConTEXT Project released ? frequently updated yes Release version update? Don t edit this page, just click on the version number programming language Delphi programming language Delphi operating system Microsoft Windows language english german genre Text editor license New BSD License website http www.contexteditor.org www.contexteditor.org distinguish ConTeXtConTEXT is a text editor for Microsoft Windows that can open and edit very large files, while requiring only modest amounts of RAM and hard drive space to run. It has built in Syntax highlighting syntax highlighters for C programming language C C , Delphi programming language Delphi Pascal programming language Pascal , FORTRAN , 80x86 assembler, Java programming language Java , JavaScript , Visual Basic , Perl Common Gateway Interface CGI , HTML , SQL , Python programming language Python , PHP , Tcl Tk , and its own syntax highlighter definition language. Other features are code templates and the ability to work with several document windows using the Multiple Document Interface . ConTEXT can integrate ... www.contexteditor.org Freeware Text Editor http www.contexteditor.org downloads ConTEXT Downloads Windows software stub Category Windows text editors Category Windows only freeware fr ConTEXT it ConTEXT hu ConTEXT nl ConTEXT pl ConTEXT fi ConTEXT ... more details
Wiktionary Wikipedia Books ContextContext may refer to Context language use , the relevant constraints of the communicative situation that influence language use, language variation, and discourse Archaeological context , an event in time which has been preserved in the archaeological record Operational context , a temporarily defined environment of cooperation Computing Context computing , the virtual environment required to suspend a running software program Context menu , a menu in a graphical user interface that appears upon user interaction ConTeXt , a macro package for the TeX typesetting system ConTEXT , a text editor for Microsoft Windows Other Opaque context Trama mycology context or flesh , the mass of non hymenial tissues that composes the mass of a fungal fruiting body See also lookfrom intitle Contextual disambiguation Contextualization disambiguation Locality disambiguation State disambiguation disambig de Kontext es Contexto fr Contexte nl Context simple Context sk Kontext ... more details
Lemma may refer to wiktionary Lemma mathematics , a proven statement used as a stepping stone toward the proof of another statement Lemma linguistics , the canonical form of a word Headword , in lexicons Lemma logic , which is simultaneously a premise for a contention above it and a contention for premises below it Lemma botany , one of the specialised bracts enclosing a floret in a grass inflorescence Shadowing lemma , a fictional animal in Terry Pratchett s Discworld series In the Ethiopian language, Amharic , lemma is a past tense meaning became green , developed , flourished . It is also a proper noun masculine in gender as there are people whose name is Lemma . In Ethiopia and in Oromigna , Lemma lema is the number two 2 . Misspellings Analemma , the curve traced out by the sun over the course of a year, and the phenomenon may be used as a clock or calendar Morris Iemma Note spelling with a capital i , former premier of the Australian state of New South Wales disambig cs Lemma da Lemma de Lemma el fr Lemme io Lemo id Lemma it Lemma lb Lemma nl Lemma simple Lemma ... more details
In the theory of formal language s, Ogden s lemma provides an extension of flexibility over the pumpinglemma for contextfree language s. Ogden s lemma states that if a language L is contextfree, then there exists some number p 0 where p may or may not be a pumping length such that for any string w of length at least p in L and every way of marking p or more of the positions in w , w can be written as w uvxyz with strings u , v , x , y , and z , such that x has at least one marked position, either u and v both have marked positions or y and z both have marked positions, vxy has at most p marked positions, and uv sup i sup xy sup i sup z is in L for every i &ge 0. Ogden s lemma can be used to show that certain languages are not contextfree, in cases where the pumpinglemma for contextfreelanguages is not sufficient. An example is the language a sup i sup b sup j sup c sup k sup d sup l sup i 0 or j k l . It is also useful to prove the Ambiguous grammar Inherently ambiguous languages inherent ambiguity of some languages. Observe that when every position is marked, this lemma is equivalent to the pumpinglemma for contextfreelanguages. See also Pumpinglemma for contextfreelanguagesPumpinglemma for regular languages References cite journal author Ogden, W. title A helpful result for proving inherent ambiguity journal Mathematical Systems Theory volume 2 year 1968 pages 191 194 doi 10.1007 BF01694004 issue 3 cite book author Hopcroft, Motwani and Ullman year 1979 title Automata Theory, Languages, and Computation publisher Addison Wesley isbn 8178083477 Category Formal languages Category Lemmas de Ogdens Lemma fr Lemme d Ogden hr Ogdenova lema it Lemma di Ogden ja pl Lemat Ogdena ru zh ... more details
Unreferenced date July 2007 Sewage pumping is normally done by a submersible pump . This became popular in the early 1960 s, when a guide rail system was developed to lift the submersible pump out of the pump station for repair, and ended the dirty and sometimes dangerous task of sending people into the sewage or wet pit. Growth of the submersible pump for sewage pumping since has been dramatic, as an increasing number of specifiers and developers learned of their advantages. Three classes of submersible pumps exist Smaller submersible pumps, used in domestic and light commercial applications, normally handle up to 55mm spherical solids and range from 0.75kW to 2.2kW. Larger submersible pumps, handle 65mm and larger solids and normally have a minimum of 80mm discharge. They are generally used in municipal and industrial applications for pumping sewage and all types of industrial wastewater. Submersible chopper pumps , which are used to handle larger concentrations of solids and or tougher solids that conventional sewage pumps cannot handle. Chopper pumps are generally used in municipal and industrial wastewater applications and provide clog free operation by maceration sewage macerating those solids that might clog other types of submersible pumps. Submersible pumps are normally used in a packaged pump station where drainage by gravity is not possible. Vertical type sewage pumps have also been used for many years. They have the motor above the floor so work on the motor can be done without entering the sewage pit. See also Sewage treatment Pumping station Packaged pump station Submersible pump Chopper pumps Literature D. Weismann, T. Gutzeit Kommunale Abwasserpumpwerke. 2nd edition, VULKAN Verlag, Germany 2006, ISBN 978 3 8027 2843 3 D. Weismann, M. Lohse Sulfid Praxishandbuch der Abwassertechnik Geruch, Gefahr, Korrosion verhindern und Kosten beherrschen 1st edition, VULKAN Verlag, Germany 2007, ISBN 978 3 8027 2845 7 DEFAULTSORT Sewage Pumping Category Sewerage infrastructure ... more details
unreferenced date March 2011 Solute pumping is a form of active transport through a cell membrane Solute pumping allows a molecule that cannot regularly cross the lipid bilayer to enter the Cell biology cell by way of a protein channel , however solute pumping requires Adenosine triphosphate ATP to change the shape of the protein channel to allow the molecule to pass through, therefore it is a form of active transport . Category Membrane biology ... more details
Context sensitive is an adjective meaning depending on context or depending on circumstances . It may refer to Context sensitive grammar Context sensitive language Context sensitive help Context sensitive user interface in computing disambig ... more details
Image Gemaal van sasse.jpg thumb 300px Pumping station Van Sasse in Grave Netherlands Grave , the Netherlands. Image Gemaal van sasse interieur.jpg thumb 200px Pumping station Van Sasse in Grave Netherlands Grave , the Netherlands. Pumping stations are facilities including pump s and equipment for pumping ... sites. A pumping station is, by definition, an integral part of a pumped storage hydroelectricity installation. Canal water supply In countries with canal systems, pumping stations are also frequent ... source is available, a pumping station can be used to maintain the water level. An excellent example of a canal pumping station is the Claverton Pumping Station on the Kennet and Avon Canal in southern ... ref Where no external water supply is available, back pumping systems may be employed. Water is extracted ... Image MetariePumpingStation6RiverSide.jpg thumb 200px New Orleans , United States Metairie Pumping Station, also known as Pumping Station 6, building, constructed in 1899, near Metairie Road and the head ..., and in the United Kingdom they built pumping stations with water pump s, powered by steam ... of sedimentary mud that created the land initially. Elsewhere, pumping stations are used ... in Drainage in New Orleans New Orleans , for example . Package pumping station In more recent times, a package pumping station provides an efficient and economic way of installing a drainage system. They are suitable for mechanical building services collection and pumping of liquids like surface water, wastewater or sewage from areas where drainage by gravity is not possible. A package pumping station ... with civil work and site labour. Sewerage systems Pumping stations in sewage collection systems, also ... usually a treatment plant. By this method, pumping stations are used to move waste to higher ... of the pumping station, a backup in the sewer system can occur, leading to a sanitary sewer overflow the discharge of raw sewage into the environment. Sewage pumping stations are typically designed so ... more details
globalize USA date August 2010 Traffic pumping , also known as access stimulation , ref name gblog10 cite web url http googlepublicpolicy.blogspot.com 2009 10 sex conference calls and outdated fcc.html title Sex, conference calls, and outdated FCC rules author Richard Whitt publisher Google Inc. work http googlepublicpolicy.blogspot.com Google Public Policy Blog date October 9, 2009 ref is a controversial practice by which some local exchange carrier local exchange telephone common carrier carrier s in rural areas of the United States inflate the volume of incoming calls to their networks, and profit ... rates work Seattle Times author Bruce Meyerson date May 7, 2007 ref as of 2010 03 , traffic pumping ... 09 sprint nextel fights traffic pumping schemes title Sprint Nextel fights Traffic Pumping Schemes date ... The Economic Impact of Free Conference Calling Services author Dr. Alan Pearce & Dr. Brian Barrett ... calling plan prices unless regulators address the issue of traffic pumping. However, providers of traffic ... to avoid these costs by blocking their customers from calling the phone numbers of traffic pumping ... to carriers meeting a traffic pumping profile were estimated to cost 95 million annually, representing ... is estimated to be more than 190 million annually. ref name traffic pumping study cite web url http www.connectiv solutions.com connectiv solutions releases traffic pumping study.html title The Impact of Traffic Pumping author Brian Silvestri, Hulya Altinsoy, Chris King and Jovita Sequeira ... with their calling destinations. In order to avoid paying high connection fees to traffic pumping ... urges the FCC to revise outdated carrier compensation rules to end the practice of traffic pumping ... pumping numbers gives it a substantial cost advantage over traditional carriers. ref name attletter ... AT&T agrees with Google that the FCC should act to forbid traffic pumping schemes in the first place ... where rural carriers profit from traffic pumping. Sam Gustin of DailyFinance suggests that there may ... more details
Image Ruby laser pumping cavity assembled and disassembled.JPG thumb 350px A ruby laser head. The photo on the left shows the head unassembled, revealing the pumping cavity, the rod and the flashlamps. The photo on the right shows the head assembled. Laser pumping is the act of energy transfer from an external ... been used, such as Chemical reaction chemical or nuclear reaction s. Optical pumping main Optical pumpingPumping cavities A laser pumped with an arc lamp or a flashlamp is usually pumped through the lateral ... impurity or a glass tube containing a liquid dye, in a condition known as side pumping. To use the lamp ... most of the lamp s energy into the rod or dye cell. Image Various laser pumping cavity cross section shapes.JPG thumb 300px Various laser pumping cavity configurations. In the most common ... pumping, increasing beam quality, however. ref name ReferenceA Another configuration uses a rod ... by Walter Koechner Springer Verlag 1965 Page 193 194 ref Pumping with a single lamp tends to focus ..., shortening lamp life. Flashlamp pumping Image Three xrenon flashtubes and a krypton arc lamp.JPG thumb 300px Laser pumping lamps. The top three are xenon flashlamps while the bottom one is a krypton ... for a faster rise time . ref cite journal title Design and analysis of flashlamp systems for pumping ... York Academy of Sciences ref Dye lasers sometimes use axial pumping, which consists of a hollow, annular .... The dye cell is placed in the middle, providing a more even distribution of pumping light, and more ..., and is best for pumping infrared lasers such as Nd YAG laser Nd YAG and Erbium YAG laser erbium YAG ... toward the visual spectrum, which is better for pumping visible light lasers, such as Ruby ... krypton is often used for pumping neodymium doped laser rods. This is because the spectral lines ... is usually chosen when pumping Nd YAG with krypton, but since all of xenon s spectral lines miss the absorption bands of Nd YAG, when pumping with xenon the continuum emission is used. ref name Walter ... more details
Buccal pumping is a method of respiration physiology respiration in which the animal moves the floor of the mouth in a rhythmic manner that is externally apparent. This method has several stages. These will be described for an animal starting with lungs in a deflated state First, the glottis opening to the lung s is closed, and the nostril s are opened. The floor of the mouth is then depressed lowered , drawing air in. The nostrils are then closed, the glottis opened, and the floor of mouth raised, forcing the air into the lungs for gas exchange. To deflate the lungs, the process is reversed. Gular pumping refers to the same process, but accomplished by expanding and contracting the entire throat to pump air, rather than just relying upon the mouth. This method of ventilation is inefficient, but is nonetheless used by all air breathing amphibian s and gular pumping is utilized to a varying extent by various reptile species ref name gular cite journal doi 10.1126 science.284.5420.1661 last Owerkowicz first Tomasz authorlink coauthors Colleen G. Farmer, James W. Hicks, Elizabeth L. Brainerd title Contribution of Gular Pumping to Lung Ventilation in Monitor Lizards journal Science volume 284 issue 5420 pages 1661 1663 publisher www.sciencemag.org date 4 June 1999 pmid 10356394 ref . Mammal s, in contrast, use the thoracic diaphragm to inflate and deflate the lungs more directly. References references image Buccal pumping.jpg center thumb 800px DEFAULTSORT Buccal Pumping Category Vertebrate anatomy respiratory stub ... more details
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