of this term, see Pseudorandom number generator In theoretical computer science , a pseudorandomgenerator PRG is a deterministic algorithm deterministic procedure that produces a pseudorandom distribution ... sup , where s n , is a pseudorandomgenerator against F sub n sub with bias if for every f in F sub ... the seed length and the quantity n s is called the stretch of the pseudorandomgenerator. Functions from the class F sub n sub are sometimes called adversaries . A pseudorandomgenerator against a family of adversaries F F sub n sub with bias n is a collection of pseudorandom generators G sub n sub 0, 1 sup s n sup 0, 1 sup n sup , where G sub n sub is a pseudorandomgenerator against ... , and one is interested in desigining a pseudorandomgenerator that is computable in the same or some closely related model. Pseudorandom generators in cryptography In cryptography , the class F usually ... is equivalent to the existence of one way function s see Pseudorandomgenerator theorem . Applications ... of key length. Key length can be significantly reduced using a pseudorandomgenerator if perfect security ... pseudorandomgenerator against F whose seed length is as short as possible. The deterministic ... generator and averaging the outputs produced by the algorithm as the pseudorandomgenerator ... s n is an arbitrary polynomial, the seed length of the pseudorandomgenerator is O log n and its bias is . In 1991, Noam Nisan and Avi Wigderson provided a candidate pseudorandomgenerator with these properties ... is a pseudorandomgenerator assuming that there exists a computational problem decision ... bit output, and one is interested in designing pseudorandom generators that are computable by a polynomial time algorithm and whose bias is negligible in the circuit size. These pseudorandom generators are sometimes called cryptographically secure pseudorandom generators CSPRGs . It is not known if cryptographic pseudorandom generators exist. Their existence would imply that P NP . However, the existence ... more details
In computational complexity theory and cryptography , the existence of pseudorandomgenerator s is related to the existence of one way function s through a number of theorems, collectively referred to as the pseudorandomgenerator theorem . Introduction Pseudorandomness A distribution is considered pseudorandom ... . Pseudorandom generators A function G sub l sub 0,1 sup l sup 0,1 sup m sup , where l m is a pseudorandomgenerator if G sub l sub can be computed in time polynomial in l G sub l sub x is pseudorandom, when x is uniformly random. One additional pseudorandom bit implies polynomially more pseudorandom bits It can be shown that if there is a pseudorandomgenerator G sub l sub 0,1 sup l sup 0,1 sup l 1 sup , i.e. a generator that adds only one pseudorandom bit, then for any m poly l , there is a pseudorandomgenerator G sub l sub 0,1 sup l sup 0,1 sup m sup ... and used as the seed to the first instance of G sub l sub , which is known to be a pseudorandomgenerator ... is not a pseudorandomgenerator, which is a contradiciton to the hypothesis. Q.E.D. Now, let s illustrate ... see references for detailed proofs. PRG &rarr OWF Consider a pseudorandomgenerator G sub l sub ... contradicts our assumption of G sub l sub being a pseudorandomgenerator. Q.E.D. OWF &rarr PRG For this case we prove a weaker version of the theorem One way permutation pseudorandomgenerator A one way permutation is a one way function that is also a permutation of the input bits. A pseudorandomgenerator ... by contradiction. Assume that G sub l sub is not a pseudorandomgenerator that is, there exists circuit ... 864, 1984. J. Hastad, R. Impagliazzo, L.A. Levin and M. Luby. A PseudorandomGenerator from any One ... D sub n sub is pseudorandom if for any polynomial size circuit C , and any inversely polynomial ... of the output. Repeating this process for m times yields an output of m pseudorandom bits. It can be shown that such G sub l sub , that consists of m instances of G sub l sub , is indeed a pseudorandom ... more details
Citation style date September 2009 A pseudorandom number generator PRNG , also known as a deterministic random bit generator DRBG , ref http csrc.nist.gov publications nistpubs 800 57 sp800 57 Part1 revised2 ... to truly random can be generated using hardware random number generator s, pseudorandom numbers .... Most pseudorandomgenerator algorithms produce sequences which are uniform distribution discrete uniformly ... Pseudorandom Number Generator Category Pseudorandom number generators cs Gener tor pseudon hodn ch ... are linear congruential generator s, Lagged Fibonacci generator s, linear feedback shift register ... feedback shift registers. Recent instances of pseudorandom algorithms include Blum Blum Shub , Fortuna ... periods of exactly 2 sup var n var sup 1. Linear congruential generator s have periods that can be calculated ... the random number generator of choice for statistical simulations and generative modeling. SFMT, SIMD ... Cryptographically secure pseudorandom number generators Main Cryptographically secure pseudorandom number generator A PRNG suitable for cryptography cryptographic applications is called a cryptographically ... only negligible function negligible advantage cryptography advantage in distinguishing the generator ... any given sub sequence, any previous or future values in the sequence, nor any inner state of the generator ... from an inner state of the generator, any previous numbers in the sequence or any previous inner generator states. For cryptographic applications, only generators meeting the K3 or K4 standard are acceptable ... Rayleigh and Poisson distribution Poisson . See also Portal Mathematics List of pseudorandom number generators Mersenne twister Monte Carlo method Multiply with carry Pseudorandom binary sequence Quasi random Random number generator Random number generator attack Randomized algorithm Randomness ... Generator Library . A free BSD licenses BSD license state of the art C pseudo random number generator ... src prng A collection of algorithms for generating pseudorandom numbers as a library of C functions ... more details
A cryptographically secure pseudo random number generator CSPRNG is a pseudo random number generator PRNG with properties that make it suitable for use in cryptography . Many aspects of cryptography require random numbers, for example Key generation Cryptographic nonce Nonces One time pad s salt cryptography ... be a hardware random number generator or perhaps unpredictable system processes &mdash though ... 50 . Andrew Yao proved in 1982 that a generator passing the next bit test will pass all other polynomial ... when available and, strictly speaking, are not pure pseudorandom number generators, as their output ... cipher s work by generating a pseudorandom stream of bits that are combined almost always XOR cipher XOR ed with the plaintext running the cipher on a counter will return a new pseudorandom stream ... about chap5.pdf Chapter 5 Pseudorandom Bits and Sequences PDF ref Each time a random number is required ... for Random and Pseudorandom Number Generators , http csrc.nist.gov publications nistpubs 800 22 rev1 ... pseudo random number generator PRNG . http blogs.msdn.com michael howard archive 2005 01 14 353379.aspx ... Random Number Generator , Daniel R. L. Brown and Kristian Gjosteen, IACR ePrint 2007 048. To appear in CRYPTO 2007. http eprint.iacr.org 2006 190 Cryptanalysis of the Dual Elliptic Curve PseudorandomGenerator , Berry Schoenmakers and Andrey Sidorenko, IACR ePrint 2006 190. http eprint.iacr.org 2006 321 Efficient Pseudorandom Generators Based on the DDH Assumption , Reza Rezaeian Farashahi and Berry ... of the Linux Random Number Generator , Zvi Gutterman and Benny Pinkas and Tzachy Reinman. http hg8lhs.ham.hu linuxbsd crypto4o.tar.gz An implementation of a cryptographically safe shrinking pseudorandom number generator. Interlang crypto navbox DEFAULTSORT Cryptographically Secure Pseudorandom Number Generator Categories Category Cryptographic algorithms Category Pseudorandom number generators Category Cryptographically secure pseudorandom number generators Category Cryptographic primitives ... more details
Pseudorandom number generator n sequence pseudorandomness white noise References references cdma ...In cryptography , pseudorandom noise PRN is a Signalling telecommunication signal similar to noise physics noise which satisfies one or more of the standard tests for statistical randomness . Although it seems to lack any definite pattern , pseudorandom noise consists of a deterministic sequence of Pulse signal processing pulses that will repeat itself after its period. ref FS1037C MS188 ref In cryptography cryptographic device s, the pseudorandom noise pattern is determined by a key cryptography key and the repetition period can be very long, even millions of years. Pseudorandom noise is used in some synthesizer electronic musical instruments , either by itself or as an input to subtractive synthesis , and in many white noise machine s. In spread spectrum systems, the receiver correlation correlates a locally generated signal with the received signal information theory signal . Such spread spectrum systems require a set of one or more codes or sequences such that Like random noise, the local sequence has a very low correlation with any other sequence in the set, or with the same sequence at a significantly different time offset, or with narrowband interference, or with thermal noise. Unlike random noise, it must be easy to generate exactly the same sequence at both the transmitter and the receiver, so the receiver s locally generated sequence has a very high correlation with the transmitted sequence. In a direct sequence spread spectrum system, each bit in the pseudorandom binary sequence is known as a chip and the inverse of its period as chip rate . Compare bit rate and baud . In a frequency hopping spread spectrum sequence, each value in the pseudorandom sequence is known as a channel number and the inverse of its period as the hop rate . FCC Part 15 mandates at least 50 different channels and at least a 2.5 Hz hop rate for narrowband frequency hopping systems. PN ... more details
wiktionarypar generatorGenerator may refer to Electrical generator Engine generator , an electrical generator, but with its own engine. Generator mathematics , any of several closely related usages in mathematics. Computing Generator computer science , a specialized routine that acts like an iterator A program which produces a Stream computing stream of data Pseudorandom number generator , producer of a sequence of random or nearly random numbers Prime number generator , a producer of the ordered sequence of prime number s A zero generator, the pseudo device dev zero outputs a never ending stream of zero valued bytes Code generation Code generator , a program which creates source code as its output anything that creates source code automatically in generative programming Natural language generation Natural language generator , a program that produces human language from a machine representation Generator matrix , a matrix whose rows can generate all the elements of a linear code Random test generator , used in functional verification of microprocessor microprocessors . Music Generator song Generator song , a song by The Foo Fighters Generator The Holloways song Generator The Holloways song , a song by The Holloways Generator Bad Religion album Generator Bad Religion album , an album by punk band Bad Religion, and its opening track Generator Aborym album Generator Aborym album The Generators , a punk rock band formed in Los Angeles in 1997 by members of the defunct Warner Bros. band Schleprock Kix band , an American glam metal band also known as the Generators Popular culture A Generator in the anime Generator Gawl is a metal organic hybrid organism with far greater powers than that of a human. See also Generate disambiguation Ginerator disambig cs Gener tor fr G n rateur it Generatore hu Gener tor egy rtelm s t lap nl Generator nn Generator pl Generator pt Generator ru sk Gener tor sv Generator olika betydelser ta uk ... more details
In cryptography , the term pseudorandom permutation , abbreviated PRP , refers to a function that cannot be distinguished from a random permutation that is, a permutation selected at random with uniform probability, from the family of all permutations on the function s domain with practical effort. A pseudorandom permutation family is a collection of pseudorandom permutations, where a specific permutation may be chosen using a key. The idealized abstraction of a block cipher is a truly random permutation. If a distinguishing algorithm exists that achieves significant advantage cryptography advantage with less effort than specified by the block cipher s security parameter this usually means the effort required should be about the same as a brute force search through the cipher s key space , then the cipher is considered broken at least in a certificational sense, even if such a break doesn t immediately lead to a practical security failure. See also Block cipher pseudorandom permutation families operating on fixed size blocks of bits Format Preserving Encryption pseudorandom permutation families operating on arbitrary finite sets Pseudorandom function Permutation box References cite book author Mihir Bellare , Phillip Rogaway date 2005 09 20 title Introduction to Modern Cryptography url http www cse.ucsd.edu mihir cse207 classnotes.html chapter Chapter 3 Pseudorandom functions accessdate 2007 09 30 crypto stub Category Theory of cryptography ... more details
Orphan date February 2009 A pseudorandom encoder is an electro mechanical device used for measuring distance and finding position. It is different from the conventional absolute and incremental encoder in its disk pattern, which gives it aspects of the other two designs. The disk of a pseudorandom encoder has an evenly spaced notch design just as an incremental encoder to measure distance. A second track of code is used to find the position just like an absolute encoder however, an absolute encoder tells position from reading from multiple parallel tracks while a pseudorandom encoder uses one single track. This aspect allows pseudorandom rotary encoders to have smaller diameters and larger through holes. To know its position, the encoder must first move a certain distance to read the code. This distance is generally small, about 1 2 degrees for rotary encoders and 1 mm for linear encoders, though this idiosyncrasy does hinder its usefulness in some applications such as trackball track balls since position is not immediately known when the system starts. ref cite web url http www.virtualabsolute.com VAoverview.htm title A New Kind of Encoder virtualabsolute.com ref See also Rotary encoder References reflist Category Dimensional instruments ... more details
Let math U U n n in mathbb N math be a uniform ensemble and math X X n n in mathbb N math be an distribution ensemble ensemble . The ensemble math X math is called pseudorandom if math X math and math U math are Computationally indistinguishable indistinguishable in polynomial time . References Goldreich, Oded 2001 . Foundations of Cryptography Volume 1, Basic Tools . Cambridge University Press. ISBN 0 521 79172 3. Fragments available at the http www.wisdom.weizmann.ac.il oded frag.html author s web site . Category Algorithmic information theory Category Pseudorandomness Category Cryptography crypto stub ... more details
In cryptography , a pseudorandom function family , abbreviated PRF , is a collection of efficiently computable Function computer science functions which emulate a random oracle in the following way no efficient algorithm can distinguish with significant Advantage cryptography advantage between a function chosen randomly from the PRF family and a random oracle a function whose outputs are fixed completely at random . Pseudorandom functions are vital tools in the construction of cryptographic primitive s, especially secure encryption encryption schemes . Pseudorandom functions are not to be confused with pseudorandom number generatorpseudorandom generators PRGs . The guarantee of a PRG is that a single output appears random if the input was chosen at random. On the other hand, the guarantee of a PRF is that all its outputs appear random, regardless of how the corresponding inputs were chosen, as long as the function was drawn at random from the PRF family. A pseudorandom function family can be constructed from any pseudorandomgenerator, using, for example, the construction given by Goldreich, Shafi Goldwasser Goldwasser , and Micali. ref Oded Goldreich , Shafi Goldwasser , Silvio Micali 1986 How to Construct Random Functions , Journal of the ACM , vol.33, no.4, p.792 807. doi 10.1145 6490.6503 http theory.lcs.mit.edu cis pubs shafi 1986 jacm.pdf preprint http www.math.weizmann.ac.il oded ggm.html web page and preprint ref See also Pseudorandom permutation References references Category Theory of cryptography Category Cryptographic primitives Category Pseudorandomness he ... more details
A binary sequence BS is a sequence of math N math bits, math a j math for math j 0,1,...,N 1 math , i.e. math m math ones and math N m math zeros. A BS is pseudorandomness pseudo random PRBS if its autocorrelation function math C v sum j 0 N 1 a ja j v math has only two values math C v begin cases m, mbox if v equiv 0 mbox mod N mc, mbox otherwise end cases math where math c frac m 1 N 1 math is called the duty cycle of the PRBS. A PRBS is random in a sense that the value of an math a j math element is independent of the values of any of the other elements, similar to real random sequences. It is pseudo because it is deterministic and after math N math elements it starts to repeat itself, unlike real random sequences, such as sequences generated by radioactive decay or by white noise. The PRBS is more general than the n sequence , which is a special pseudo random binary sequence of n bits generated as the output of a linear shift register. An n sequence always has a 1 2 duty cycle and its number of elements math N 2 k 1 math . PRBS s are used in telecommunication , encryption , simulation , correlation technique and time of flight spectroscopy . Practical implementation Pseudorandom binary sequences can be generated using linear feedback shift register s. ref Paul H. Bardell, William H. McAnney, and Jacob Savir, Built In Test for VLSI Pseudorandom Techniques , John Wiley & Sons, New York, 1987. ref See also Pseudorandom number generator Gold code Complementary sequences Bit Error Rate Test References reflist External links http www.scriptwell.net correlation.htm Refimprove date January 2008 Category Pseudorandomness Category Binary sequences de Pseudo random bit stream pl PRBS ru ... more details
orphan date February 2010 In theoretical computer science a pseudorandomgenerator for low degree polynomials is an efficiently computable function whose output is indistinguishable from the uniform distribution by evaluation of low degree polynomials in the following sense. Definition A pseudorandomgenerator math G mathbb F s rightarrow mathbb F n math for polynomials of degree math d math over a Finite field F is an efficient procedure that stretches math s n math field elements into math n math field elements and fools any polynomial of degree d in n variables over F For every such polynomial p, the Total variation Total variation distance in probability theory statistical distance between the distributions math p U n math , for uniform math U n math in math mathbb F n math , and math p G U s math , for uniform math U s math in math mathbb F s math , is at most a small math epsilon math . Construction The case of linear polynomials is solved by Epsilon Biased Sample Spaces small bias spaces which give constructions with seed length math s O log n log 1 epsilon math this is optimal up to constant factors . Following the sequence of papers http www.ccs.neu.edu home viola papers gen.pdf , http shachar.lovett.googlepages.com prg poly.pdf it was established in http www.ccs.neu.edu home viola papers d.pdf that a sum of math d math small bias spaces fools degree math d math polynomials. This gives a construction with seed length math s O log n 2 d log 1 epsilon math . References http www.ccs.neu.edu home viola papers gen.pdf The paper proposed taking a sum of independent small bias spaces for fooling low degree polynomials . http shachar.lovett.googlepages.com prg poly.pdf The paper gave the first unconditional result showing that sum of math 2 d math small bias spaces fools low degree polynomials . http www.ccs.neu.edu home viola papers d.pdf The paper shows that sum of math d math small bias spaces fools low degree polynomials . Category Pseudorandomness ... more details
generator Generalized inversive congruential pseudorandom numbers Notes Reflist refs ref name ... f a 1 math and math f a 5 math . There are other attacks that would be very bad for a Pseudorandom Number Generator the user expects to get random numbers from the output, so of course the stream should ..., g by math mathcal I mathcal G n math , instance generator, and the random choice of the function ... math mathbf D a math be the Inversive congruential generator discrepancy of the set math f a x ... and Pseudorandomness year 1998 edition first publisher Springer isbn 978 3540647669 Category Pseudorandom ... more details
Unreferenced date January 2009 In cryptography , the shrinking generator is a form of pseudorandom number generator intended to be used in a stream cipher . It was published in Crypto 1993 by Don Coppersmith , Hugo Krawczyk , and Yishay Mansour . The shrinking generator uses two linear feedback shift register s. One, called the A sequence, generates output bits, while the other, called the S sequence, controls their output. Both A and S are clocked if the S bit is 1, then the A bit is output if the S bit is 0, the A bit is discarded, nothing is output, and we clock the registers again. This has the disadvantage that the generator s output rate varies irregularly, and in a way that hints at the state of S this problem can be overcome by buffering the output. Despite this simplicity, the shrinking generator has remained remarkably resistant to cryptanalysis there are currently no known attacks better than exhaustive search when the feedback polynomials are secret. An interesting variant is the self shrinking generator . An implementation of a shrinking generator in Python This example uses two Galois LFRSs to produce the output pseudorandom bitstream. The python code can be used to encrypt and decrypt a file or any bytestream. source lang python usr bin python import sys Crypto4o functions start here class glfsr def init self, polynom, initial value self.polynom polynom 1 self.data initial value tmp polynom self.mask 1 while tmp 0 if tmp & self.mask 0 tmp tmp self.mask if tmp 0 break self.mask self.mask 1 def next state self self.data self.data 1 retval 0 if self.data & self.mask 0 retval 1 self.data self.data self.polynom return retval class sprng def init self, polynom d, init value d, polynom c, init value c self.glfsr d glfsr polynom d, init value d self.glfsr c glfsr ... pseudorandom number generator. DEFAULTSORT Shrinking Generator Category Stream ciphers Category Pseudorandom ... cipher FISH , an insecure stream cipher based on the shrinking generator principle External links http ... more details
In mathematics , the term infinitesimal generator may refer to an element of the Lie algebra associated to a Lie group the Infinitesimal generator stochastic processes infinitesimal generator of a stochastic processes stochastic process the C0 semigroup Infinitesimal generator infinitesimal generator of a strongly continuous semigroup . disambig ... more details
Merge Icemaker date December 2009 This article is about the machine or system which can produce the water ice. File tube ice machine 1.jpg thumb right alt Tube ice machine alt text 20T day tube ice machine Definition of ice generator The ice generator is the broader name for both ice machine and ice making system. It is also called ice machine, ice maker and ice making system. It was firstly invented by Florida physician John Gorrie on July 14, 1850. ref http www.wired.com science discoveries news 2008 07 dayintech 0714 America s first public demonstrated ice generator By Randy Alfred www.wired.com ref It can be classified into commercial ice generator and home ice generator by its usage. Normally, commercial ice generator can produce more than 18 kg of ice per day, also divided into several categories by the shapes of ice it s making. Generally, commercial ice generators are flake ice generator, block ice generator, tube ice tube ice generator , plate ice generator, cube ice generator, shell ice generator, nugget ice generator and snow generator. Home ice generator also can be divided into different types among cube ice generator, nugget ice generator, and shell ice generator. File Focusun TypeT Evaperator.jpg thumb left alt Focusun TypeT evaporator alt text TypeT Evaporator Ice generator mechanism According to the invention of ice generator , ice generator comprises an ice generating device and an ice dispensing device. The ice generating device comprises a dish filled with water, and a number of evaporating appendixes, which are immersed in the water inside the dish, and to exchange heat with Freon circuits from outside to form ice on them. The ice dispensing device comprises a mechanism for rotating the dish into a position in which to pour out the water and allow the ice detached from the appendixes to drop freely beneath the dish and an ice guide mechanism for guiding the ice to drop through the outlet from the appendixes. ref http www.sumobrain.com patents wi ... more details
A steam generator is a device used to boil water to create steam. It may refer to Boiler steam generator , a closed vessel in which water is heated under pressure Steam generator nuclear power , a heat exchanger in a pressurized water nuclear reactor Steam generator railroad , a device used in trains to provide heat to passenger cars Disambig ja no Dampgenerator andre betydninger ... more details
Orphan date October 2008 The summation generator , created in 1985, by Rainer Rueppel, was a cryptography and security front runner in the late 1980s. It operates by taking the output of two LFSR s through an adder with carry. The operation s strength is that it is nonlinear . However, through the early 1990s various attacks against the summation generator eventually led to its fall to a correlation attack. In 1995 Klapper and Goresky were able to determine the summation generator s sequence in only 2 sup 19 sup bits. An improved summation generator with 2 bit memory was then proposed by cryptographers Lee and Moon. In the new generator scheme an extra bit of memory is added to the nonlinear combining Function mathematics function . The objective in the modification was to make the summation generator immune to correlation attack . An attack against the improved summation generator was reported by Mex Perera and Shepherd in 2002 by exploting linear relations. Besides, in June 2005 an algebraic attack was developed. Using this attack a PC can calculate the initial state of the summation generator within 3 minutes even with 256 bit LFSR s References R. A. Rueppel, Correlation immunity and the Summation Generator, Advances in Cryptography EUROCRYPT 85 proceedings, Berlin Springer Verlag, 1986, pp. 260 272. W.Meier and O. Staffelbach, Correlation properties of Combiners with Memory in Stream Ciphers, Advances in Cryptography EUROCRYPT 90 proceedings, Berlin Springer Verlag, 1991, pp. 204 213. Bruce Schneir, Applied Cryptography, pg. 364, Summation Generator Mex Perera, J. C. and Shepherd, S. J. 2002. Cryptanalysis of a summation generator with 2 bit memory . Signal Process. 82, 12 Dec. 2002 , 2025 2028. An algebraic attack on the improved summation generator with 2 bit memory Information Processing Letters, Volume 93 , Issue 1, January 2005 Pages 43 46 ISSN 0020 0190 External ... Generator http ciphersbyritter.com RES COMBCORR.HTM The story of combiner correlation http ... more details
Infobox Album See Wikipedia WikiProject Albums Name Harmonic Generator Type EP Artist The Datsuns Cover Harmonic Generator cover Datsuns .gif Genre Rock Producer The Datsuns Last album The Datsuns br 2002 This album Harmonic Generator Next album Outta Sight, Outta Mind br 2004 Harmonic Generator is a Japanese six track Extended play EP by New Zealand rock band The Datsuns . It contains radio sessions of three songs and live studio recordings of a further three see below for track listing . It also contains the music video for Harmonic Generator as an enhanced multimedia track. It is named after the guitar distortion pedal used on the track the Prunes & Custard Harmonic Generator Intermodulator manufactured by Crowther Audio. Track listing Harmonic Generator live Sittin Pretty live Fink for the man live Little Bruise O Woe is Me Freeze Sucker Harmonic Generator Enhanced track Category The Datsuns albums ... more details
unreferenced date January 2011 A shunt generator is a method of generating electricity in which field winding and Armature electrical engineering armature winding are connected in parallel, and in which the armature supplies both the load current and the field current. A Direct current or DC shunt generator is a type of shunt generator that requires a DC field current. A shunt generator can be parallel or in series to the armature. There are four types of shunt generators short shunt, long shunt, series, or parallel. Shunt wound In this field winding is connected in parallel with the armature conductors and have the full voltage of the generator applied across them.The field coils consist of many turns of small wire. They are connected in parallel with the load. In other words, they are connected across the output voltage of the armature. Current in the field windings of a shunt wound generator is independent of the load current currents in parallel branches are independent of each other . Since field current, and therefore field strength, is not affected by load current, the output voltage remains more nearly constant than does the output voltage of the series wound generator. In actual use, the output voltage in a dc shunt wound generator varies inversely as load current varies. The output voltage decreases as load current increases because the voltage drop across the armature resistance increases E IR . In a series wound generator, output voltage varies directly with load current. In the shunt wound generator, output voltage varies inversely with load current. A combination of the two types can overcome the disadvantages of both. This combination of windings is called the compound wound dc generator. Category Electric motors engineering stub ... more details
Unreferenced date November 2010 image FEMA 40330 Photograph by Ashley Andujar taken on 03 26 2009 in Puerto Rico.jpg thumb right Standby generators A standby generator is a back up electrical system that operates automatically. Within seconds of a utility Power outage outage an automatic transfer switch senses the power loss, commands the generator to start and then transfers the electrical load to the Electrical generator generator . The standby generator begins supplying power to the Electrical network circuits . After utility power returns, the automatic transfer switch transfers the electrical load back to the utility and signals the standby generator to shut off. It then returns to standby mode where it awaits the next outage. To ensure a proper response to an outage, a standby generator runs weekly self tests. Most units run on diesel fuel diesel , natural gas or propane liquid propane gas . Automatic standby generator systems may be required by building code s for critical safety systems such as elevators in high rise buildings, fire protection systems, standby lighting, or medical and life support equipment. Residential standby generators are increasingly common and can provide backup power to HVAC systems, security systems and will help ensure that the contents of the refrigerator stay cold. References reflist External links http www.popularmechanics.com science 4281042 Popular Mechanics How to Buy the Right Backup Generator for Your Disaster & Budget Category Power station technology ... more details
About the Foo Fighters song the Holloways song Generator The Holloways song the Bad Religion song Generator Bad Religion album Unreferenced date December 2009 Infobox Single Name Generator Cover foo fighters generator.png Artist Foo Fighters from Album There Is Nothing Left to Lose Released March 6, 2000 Europe br April 24, 2000 Australia Format Compact Disc CD Recorded 1999 Genre Alternative rock Length 3 49 Label Roswell, RCA Records Producer Last single Stacked Actors br 2000 This single Generator br 2000 Next single Breakout Foo Fighters song Breakout br 2000 Generator is a Foo Fighters band Foo Fighters song, released as a single in 2000 in Australia only and also released as a limited edition single of 20,000 copies only in Europe. It is also available on their third album There Is Nothing Left to Lose . The song is particularly unique among the band s work because of Dave Grohl s implementation of the talk box in parts of the song. The usage of the device was partly inspired by Grohl s admiration of Peter Frampton and Joe Walsh , both of whom helped popularize it in the 1970s. Dave Grohl has said that the song reminds him of his arrest on the Gold Coast, Australia. No video was filmed for the single. Instead a live performance of the song in Australia was overdubbed with the studio ... features the song Generator at the beginning on the video. Track listing Australian CD The EP also contains an enhanced CD portion. Generator Learn to Fly Live 24 January 2000 Sydney, Australia ... exclusive documentary footage and photos. Generator Ain t It the Life Live Acoustic Version Floaty ... . 7 inch Generator Fraternity Music video The music video for Generator is a performance at The Chapel ... ARIA Charts Australian Singles Chart align center 31 Foo Fighters DEFAULTSORT Generator Song Category ... written by Dave Grohl Category English language songs es Generator canci n pl Generator singel pt Generator can o fi Generator ... more details
File NagoldAggregat.jpg thumb 300px right MAN diesel engine and generator, now on outdoor museum display Mergefrom Diesel generator discuss Talk Engine generator Merge proposal date January 2009 An engine generator is the combination of an electrical generator and an engine prime mover locomotive prime ... generator set or a gen set . In many contexts, the engine is taken for granted and the combined unit is simply called a generator . Components In addition to the engine and generator, engine generators generally include a fuel supply, a constant engine speed regulator governor and a generator volt ... and connect it to the generator. Types Engine generators are available in a wide range of power ratings ... engine . The generator volt voltage volts , frequency Hz and electric power power watts ratings are selected ... a few portable three phase generator models available in the US. Most of the portable units ... that use a ballast. Mid size stationary engine generator The mid size stationary engine generator ... rpm or another divisor of 3600. Diesel engine generator sets operated at their peak efficiency point ..., with lower efficiency at part load. gallery Image Hand generator.jpg Hand driven electric generator ... Engine generator for a radio station Dubendorf museum of the military aviation . The generator worked ... Side view of a large Perkins diesel generator, manufactured by FG Wilson Engineering Ltd. This is a 100 Volt ampere kVA set. Image Generator control panel.jpg Control panel on 100 kVA Aggreko generator set Image BronsV8.jpg Emergency power Electrical generatorgenerator in a drinking water pumping station. Brons engine with Heemaf generator. Image ElectricalGeneratorGasoline.JPG Another generator, powered by fossil fuels and used at a construction site. Image Generator.jpg An engine generator. Image Portable electrical generator angle.jpg Image of a common engine generator gallery ... a redundant system is required or no generator is on site. To make the hookup faster and safer ... more details
of a modern steam turbine generator In electricity generation , an electric generator is a device .... A generator forces electrons in the windings to flow through the external electrical circuit . It is somewhat ... , in the power generating hall of a hydroelectric station Image Generator 20071117.jpg thumb right Early Ganz Generator in Zwevegem , West Flanders , Belgium Historical developments Before the connection between magnetism and electricity was discovered, electrostatic generator s were invented that used ... de Graaff generator are examples of these machines that have survived. Jedlik s dynamo main Jedlik ... thumb left Faraday disk, the first electric generator. The horseshoe shaped magnet A created a magnetic ... electromagnetic generator, called the Faraday disk , a type of homopolar generator , using a copper ... subsequent generator designs. Dynamo main Dynamo Image High Current Copper Brush Commutated Dynamo.jpg ... 284110 The dynamo was the first electrical generator capable of delivering power for industry. The dynamo ... generator . When used to feed an Grid electricity electric power grid , an alternator must always operate .... A DC generator can operate at any speed within mechanical limits but always outputs a direct current ... singly fed generator , the doubly fed electric machine doubly fed generator , or the brushless wound rotor doubly fed electric machine brushless wound rotor doubly fed generator , do not incorporate ... of any generator can be optimized with electronic control but only the doubly fed electric machine doubly fed generator s or the brushless wound rotor doubly fed electric machine brushless wound rotor doubly fed generator incorporate electronic control with power ratings that are substantially less than the power output of the generator under control, which by itself offer cost, reliability and efficiency benefits. MHD generator main MHD generator A magnetohydrodynamic generator directly extracts ... machinery. MHD generators were originally developed because the output of a plasma MHD generator ... more details
A signal generator , also known variously as function generator , pitch generator , arbitrary waveform generator , digital pattern generator or frequency generator is an Electronics electronic device that generates ... LSG 15 signal generator.jpg thumb 350px Leader Instruments LSG 15 signal generator main Function generator A function generator is a device which produces simple repetitive waveform s. Such devices ... generator s AWGs . If the oscillator operates above the audio frequency range 20 kHz , the generator ... main Arbitrary waveform generator Arbitrary waveform generators , or AWG s, are sophisticated .... Special purpose signal generators File Tone generator and wire tracker 0a.jpg thumb right A pitch generator and a probe for locating a specific pair of wires amongst many, for example in a punch ... designed for specific applications. Pitch generators and audio generators A pitch generator is a type of signal generator optimized for use in sound reproduction audio and acoustics applications ... card to generate signals only within the aural band. Video signal generators main Video signal generator A video signal generator is a device which outputs predetermined video and or television waveforms .... Regardless of the specific type, the output of a video generator will generally contain synchronization ... a full featured vector signal generator with very high modulation bandwidth. Example applications ... receiver adjacent channel rejection. See also A N URM 25D Signal Generator , Cold War era hardware ... Waveform Generator Guidebook BK Function Generator and AWG Guidebook.pdf Function Generator & Arbitrary Waveform Generator Guidebook http www.radio electronics.com info t and m generators rf signal generator specs specifications.php Understanding signal generator specifications http www.ztecinstruments.com waveform generator fundamentals Waveform Generator Fundamentals http www.ztecinstruments.com ... generator available online. Electrical and electronic measuring equipment Category Laboratory equipment ... more details
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