statistical mechanics or to entropyinformationtheoryinformationtheory , it is possible ... N N k B sum i 1 r x i ln x i n R sum i 1 r x i ln x i , math Relationship to informationtheory The entropy of mixing is also proportional to the Entropyinformationtheory Shannon entropy or compositional uncertainty of informationtheory , which is defined without requiring Stirling s approximation. Claude Elwood Shannon Claude Shannon introduced Informationentropy Formal definitions this expression for use in informationtheory , but similar formulas can be found as far back as the work of Ludwig ... species, even though they are chemically non reacting. The entropy of mixing provides information about ... theory Conditional entropy equivocation conditional probabilities , it turns out that the analytical ... solid as it is for a liquid. The Flory Huggins solution theory provides the entropy of mixing ...In thermodynamics the entropy of mixing is the increase in the total entropy of a compound system, when .... The entropy of mixing is entirely accounted for by the diffusive expansion of each material into a final ... transfer of work or heat, to or from the surroundings also there may be a departure of the entropy ... in entropy of mixing. These energy and entropy variables and their temperature dependences provide valuable information about the properties of the materials. On a molecular level, the entropy of mixing is of interest because it is a macroscopic variable that provides information about molecular properties ... concept of randomness is used for statistical mechanical explanation of the entropy of mixing. Mixing ... volumes , and the entropy of mixing math Delta S mix , math is given by math Delta S mix nR x 1 ... moles of component math i , math may explore the combined volume math V , math , which causes an entropy ..., the increase in entropy is due entirely to the irreversible processes of expansion of the two gases ... change, and the entropy of mixing considered here. For an ideal gas mixture or an ideal solution ... more details
John Scales Avery John Avery , from his recent 2003 book InformationTheory and Evolution , we find ... Cite book last Avery first John title InformationTheory and Evolution publisher World Scientific year ...Research concerning the relationship between the thermodynamics thermodynamic quantity entropy and the evolution ... volume A Letter to American Teachers of History proposing a theory of history based on the second law of thermodynamics and the principle of entropy. ref Adams, Henry. 1986 . History of the United ... feeds on negative entropy, or negentropy as it is sometimes called. Recent writings have utilized ..., 1st Baron Kelvin William Thomson , between his newly developed concept of entropy and life. Building ... which exists in plenty in any body in the form of heat, but a struggle for negative entropy , which ... on the Mechanical Theory of Heat and its Application to the Steam Engine , which was an early thermodynamics ... math S int dQ over tau math where math S math entropy math dQ math equals a differential amount of heat ..., elapsed since the Theory of heat mechanical theory of heat has been freely adopted, whole branches ... first Richard Sears title Treatise on the mechanical theory of heat and its applications to the steam ... s theory of respiration with cycles of digestion and excretion, perspiration, but then contradicts Lavoisier with recent findings, such as internal heat generated by friction, according to the new theory ... to the mechanical theory of heat and goes on to loosely outline how the heart is what he calls a force ... McCulloch1876 Rp p. 270 Negative entropy Later, building on this premise, in the famous 1944 book ... or maintains its entropy by feeding on negative entropy . ref Cite book last Schr dinger ... remarks on his usage of the term negative entropy quote Let me say first, that if I had been catering ..., which states that the entropy of an isolated system tends to increase, it does not in any way conflict or invalidate this law, because the principle that entropy can only increase or remain constant ... more details
Differential entropy also referred to as continuous entropy is a concept in informationtheory that extends the idea of Shannon informationentropyentropy , a measure of average surprisal of a random ..., the resulting notion is called relative entropy in informationtheory math D p m int p x log frac ... also InformationentropyInformationtheory Limiting density of discrete points Self information Kullback ... of InformationTheory New York Wiley, 1991. ISBN 0 471 06259 6 External links planetmath reference id 1915 title Differential entropy Category Entropy and information Category Informationtheory Category .....69f6138K ref including linear ref name Reza cite book title An Introduction to InformationTheory ... that addresses this is the relative informationentropy , also known as the Kullback Leibler divergence ... function pdf Entropy in Nat information nats Maximum Entropy Constraint Support Uniform distribution ... of continuous probability distributions InformationTheory, IEEE Transactions on, 1978. 24 1 p. 120 ... entropy math h X math or math h f math is defined as math h X int mathbb X f x log f x ,dx math . As with its discrete analog, the units of differential entropy depend on the base of the logarithm ... bases. Related concepts such as joint entropy joint , conditional entropy conditional differential entropy, and Kullback Leibler divergence relative entropy are defined in a similar fashion. One must take care in trying to apply properties of discrete entropy to differential entropy, since ... Uniform 0 , 1 2 has negative differential entropy math int 0 frac 1 2 2 log2 ,dx log2 , math . Thus, differential entropy does not share all properties of discrete entropy. Note that the continuous mutual information math I X Y math has the distinction of retaining its fundamental significance as a measure of discrete information since it is actually the limit of the discrete mutual information ... Kraskov coauthors St gbauer, Grassberger year 2004 title Estimating mutual information journal Phys ... more details
Lead missing date June 2011 Measures in informationtheory Many of the formulas in informationtheory ... sign the Kullback Leibler divergence is always non negative due to Gibbs inequality . Entropy as a measure Image Entropy mutual information relative entropy relation diagram.svg thumb 256px ... discrete mathematics discrete random variable s X and Y , somehow representing the informationentropyinformation borne by X and Y , respectively, such that math mu tilde X cap tilde Y 0 math whenever ..., conditional entropy, and bivariate mutual information of discrete random variables are all nonnegative, many basic inequalities in informationtheory among no more than two random variables can be derived ... way as the entropy of a joint distribution, and a multivariate mutual information math I ... the mutual information of a single random variable is defined to be its entropy math I X H X math ... X,Z W,Y . math References Fazlollah M. Reza. An Introduction to InformationTheory . New York McGraw ... Information . Notre Dame EE 80653 InformationTheory Tutorials, Fall 2005. http www.nd.edu jnl ee80653 ... Informationtheory Measure theory Set theory Category Informationtheory Category Measure theory .... These versions can often be generalized using measure theory . For discrete random variables, probability ... requiring only basic discrete mathematics for what can be considered, in a measure theory context, integration ... the formula for the differential entropy of a continuous random variable with probability density ... X,Y with mutual information I X Y . There is an analogy between Claude Elwood Shannon Shannon s basic Quantities of information measures of the informationentropyinformation content of random variables and a measure theory measure over sets. Namely the joint entropy , conditional entropy , and mutual information can be considered as the measure of a union set theory set union , set difference , and intersection set theory set intersection , respectively Reza pp. 106 108 . If we associate ... more details
Cleanup date May 2008 Social entropy is a Macrosociology macrosociological systems theory . It is a measure of the natural decay within a social system . It can refer to the decomposition of social structure or of the disappearance of Distinction social social distinctions . Much of the energy consumed by a social organization is spent to maintain its structure, counteracting social entropy, e.g., through legal institutions, education and even the promotion of television viewing. Anarchy is the maximum state of social entropy. Social Entropy implies the tendency of social networks and society in general to break down over time, moving from cooperation and advancement towards conflict and chaos. Social Entropy and Energy Inputs Modern Western complex societies remain organized by large inputs of energy to mitigate the natural progression of increasing entropy disorder , according to the Second Law of Thermodynamics , a fundamental law of physics. This effectively states that Entropy disorder increases with time. As the system becomes more complex, through access to energy, it becomes more susceptible to changes that may occur if one were to remove this source of energy. Take away the energy inputs largely from fossil fuels and organization corrodes, thus society becomes less cohesive and trends toward anarchy . Energy Return on Energy Invested theories A related economic model is proposed by Thomas Homer Dixon and by Charles Hall in relation to our declining productivity of energy extraction, or Energy Return on Energy Invested or EROEI. This measures the amount of surplus energy ... D. Bailey sociologist Kenneth D. Bailey 1990 . Social EntropyTheory . Albany, New York State University ... in food production again. Entropy in the context of a Micro level The typical progression of time continues to see words appended with marginally altered meanings and or contexts. Entropy is now ... of mind To refer to another person s state of mind as One of entropy or, Entropic is to cite ... more details
In informationtheory , the R nyi entropy , a generalisation of Shannon entropy , is one of a family ... Renyi entropy Category Informationtheory Category Entropy and information bar R nyi Entropie de R nyi ... cite conference author A. R nyi title On measures of information and entropy booktitle Proceedings ... Alfr d R nyi . The R nyi entropy of order math alpha math is defined for math alpha geq 0 math and math ... of . Higher values of , approaching infinity, give a R nyi entropy which is increasingly ... zero, give a R nyi entropy which increasingly weights all possible events more equally, regardless of their probabilities. The intermediate case 1 gives the Shannon entropy , which has special properties ... in ecology and statistics as diversity indices indices of diversity . The R nyi entropy is also important in quantum information , where it can be used as a measure of entanglement . In the Heisenberg XY spin chain model, the R nyi entropy as a function of can be calculated explicitly by virtue ... group . ref cite journal last Its first A. R. coauthors Korepin, V. E. title Generalized entropy ... Its, A.R., Korepin, V.E. title R nyi entropy as a measure of entanglement in quantum spin chain journal ... n log X , , math which is the logarithm of the cardinality of X , sometimes called the Hartley entropy ... H alpha math converges to math H 1 X sum i 1 n p i log p i math which is the Shannon entropy . Collision entropy , sometimes just called R nyi entropy, refers to the case math alpha 2 math , math ... log sup i 1..n p i math and this is called Min entropy , because it is the smallest value of math H ... H infty H 2 2 H infty math . On the other hand the Shannon entropy math H 1 math can be arbitrarily high for a random variable X with fixed min entropy. math H 2 2 H infty math is because math log sum ... of the probabilities. Why &alpha 1 is special The value 1, which gives the Shannon entropy and the Kullback ... x , a , and we acquire new information which only affects the distribution of a , then the distribution ... more details
In quantum mechanics , and especially quantum information processing , the entropy exchange of a quantum operation math phi , math acting on the density matrix math rho Q , math of a system math Q , math is defined as math S rho, phi equiv S Q ,R S rho QR math where math S rho QR , math is the von Neumann entropy of the system math Q , math and a fictitious Purification of quantum state purifying auxiliary system math R , math after they are operated on by math phi , math . Here, math rho QR QR rangle langle QR quad math , math mathrm Tr R rho QR rho Q quad math , and math rho QR phi rho QR quad math . References Nielsen, Michael A. and Isaac L. Chuang 2000 . Quantum Computation and Quantum Information , Cambridge University Press, ISBN 0 521 63503 9 Category Quantum information science Quantum stub ... more details
Unreferenced stub auto yes date December 2009 The entropy of vaporization is the increase in entropy when vaporizing a substance. This is always positive since the EntropyEntropy as a measure of disorder degree of disorder increases in the phase transition transition from an organized crystal line solid or a slightly less organized liquid to the extremely disorganized structure of a gas . It is denoted as S sup s o s sup sub vap sub and normally expressed in Joule J mole unit mol Kelvin K . Entropy of vaporisation is denoted by Sfg. In a phase change , both phases coexist in a equilibrium, so the Gibbs free energy is equal to zero. It follows that the entropy of vaporization is related to the boiling point and the enthalpy of vaporization math Delta H vap T vap times Delta S vap math See also Entropy of fusion Trouton s rule DEFAULTSORT Entropy Of Vaporization Category Thermodynamic entropy Category Thermodynamic properties Chem stub ar de Verdampfungsentropie it Entropia di vaporizzazione ... more details
Orphan date April 2012 Expert subject date April 2012 Entropy is simply defined as the property used to determine the amount of heat not available to do work in a system. This energy is dispelled as wasted heat. Entropy in terms of the Second Law of Thermodynamics is constantly increasing. Entropy can never decrease in a system unless the entropy of the surroundings is increased. The increased entropy must always be less than or equal to the original entropy. That is to say S sub Universe sub S sub System sub S sub Surroundings sub . Entropy and the environment File Carnot heat engine 2.svg 300px thumb right Carnot engine diagram modern where heat flows from a high temperature T sub H sub furnace through the fluid of the working body working substance and into the cold sink T sub C sub , thus forcing the working substance to do mechanical work W on the surroundings, via cycles of contractions and expansions. The Second Law of Thermodynamics may help provide explanation for why there have been increases in Earth s temperatures over the last 250 years, and many professionals are concerned that the entropy increase of the universe is a real threat to the environment. As an engine operates, heat flows from a heat tank of greater temperature to a heat sink of lesser temperature. ref cite book last Moran first Michael title Fundamentals of Engineering Thermodynamics year 2011 publisher John Wiley and Sons, Inc. location Hoboken, NJ pages 235 266 coauthors Howard H. Shapiro, Daisie D. Boettner, Margaret B. Bailey page 242 chapter 5 ref In between these states, the heat flow is turned into useful energy with the help of heat engines. As these engines operate, however, a great deal ... O. Renno title Natural Convection as a Heat Engine A Theory for CAPE journal Journal of Atmospheric ... accessdate 14 April 2012 year 2001 ref With the entropy of the environment constantly increasing, however ..., or there could be the heat death of the universe. Sources Reflist Category Thermodynamic entropy ... more details
Mergeto Entropy statistical thermodynamics date July 2009 In thermodynamics , specifically in statistical mechanics , the Boltzmann entropy is an approximation to the normal Gibbs entropy . The Boltzmann entropy is obtained if one assumes one can treat all the component particles of a thermodynamic system as statistically independent. The probability distribution of the system as a whole then factorises into the product of N separate identical terms, one term for each particle and the Gibbs entropy simplifies to the Boltzmann entropy math S B N k B sum i p i log p i , math where the summation is taken over each possible state in the 6 dimensional phase space of a single particle rather than the 6 N dimensional phase space of the system as a whole . This reflects the original statistical entropy function introduced by Ludwig Boltzmann in 1872 . For the special case of an ideal gas it exactly corresponds to the proper entropy thermodynamic entropy . However, for anything but the most dilute of real gases, it leads to increasingly wrong predictions of entropies and physical behaviours, by ignoring the interactions and correlations between different molecules. Instead one must follow Gibbs, and consider the statistical ensemble ensemble of states of the system as a whole, rather than single particle states. See also EntropyEntropy thermodynamics Boltzmann s entropy formula Gibbs entropy References reflist E.T. Jaynes Jaynes, E. T. 1965 . http bayes.wustl.edu etj articles gibbs.vs.boltzmann.pdf Gibbs vs Boltzmann entropies . American Journal of Physics , 33 , 391 8. External links DEFAULTSORT Boltzmann Entropy thermodynamics stub Category Thermodynamic entropy Category Article Feedback 5 ... more details
used in astrophysical theory of galaxy cluster s. This is what astrophysicists refer to as entropy and has units of keV cm sup 2 sup . This quantity relates to the thermodynamic entropy as math S k B ln Omega S 0 , math where math Omega , math , the density of states in statistical theory, takes on the value of K as defined above. Category Astrophysics Category Entropy ...Unreferenced date December 2008 Orphan date December 2008 In astrophysics , what is referred to as entropy is actually the adiabatic invariant adiabatic constant derived as follows. Using the first law of thermodynamics for a quasistatic process quasi static , infinitesimal process for a hydrostatics hydrostatic system math dQ dU dW. , math For an ideal gas in this special case, the internal energy , U, is only a function of the temperature T therefore the partial derivative of heat capacity with respect to T is identically the same as the full derivative, yielding through some manipulation math dQ C V dT P ,dV. math Further manipulation using the differential version of the ideal gas law , the previous equation, and assuming constant pressure, one finds math dQ C P dT V ,dP. math For an adiabatic process math dQ 0 , math and recalling math gamma frac C P C V , math , one finds math frac V ,dP C P dT P ,dV C V dT math math frac dP P frac dV V gamma. math One can solve this simple differential equation to find math PV gamma text constant K , math This equation is known as an expression for the adiabatic constant, K, also called the adiabat. From the ideal gas equation one also knows math P frac rho k B T mu m H , math where math k B , math is Boltzmann s constant . Substituting this into the above equation along with math V grams rho , math and math gamma 5 3 , math for an ideal monatomic gas one finds math K frac k B T mu m H rho 2 3 , math where math mu , math is the mean molecular weight of the gas or plasma physics plasma and math m H , math is the mass of the Hydrogen atom ... more details
reason, the increase of entropy has begun to accelerate. This effect would cause precarious ecosystems ... the Aleph Prime computers to obtain information on Mordreaux s case, only to discover the records ... Kirk s brain dead body. As Braithewaite begins to put together facts to form a working theory of conspiracy ... managed to regain his sanity, that he realised the entropy effect himself, and began working to undo ... and the acceleration of entropy increase . The strain of so many travels is too much for his .... External links memoryalpha article The Entropy Effect Star Trek publications Star Trek DEFAULTSORT Entropy Effect, The Category Star Trek novels Category Novels by Vonda McIntyre Category ... more details
Unreferenced date December 2009 Infobox Album See Wikipedia WikiProject Albums Name Entropy Type ep Artist Anathallo , Javelins Cover anathallo javelins split.jpg Released 2005 Genre Indie rock Label Potential Getaway Driver Last album Hymns EP br 2004 This album Entropy Split One Sided 12 with Javelins br 2005 Next album Floating World Anathallo album Floating World br 2006 Entropy is a split vinyl record vinyl album by Anathallo and Javelins . Each band has one song featured on the album, released in 2005 on Potential Getaway Driver . There were two pressings made, 300 in translucent green and later another 500 in clear vinyl. Track listing Entropy by Javelins Entropy by Anathallo DEFAULTSORT Entropy Album Category Split EPs Category 2005 EPs 2000s indie rock album stub ... more details
The entropy of activation is one of the two parameters typically obtained from the temperature dependence of a reaction rate, when these data are analysed using the Eyring equation . Symbolized S sup sup , the entropy of activation provides clues about the molecularity of the rate determining step in a reaction, i.e. whether the reactants are bonded to each other, or not. Positive values suggest that entropy increases upon achieving the transition state, which often indicates a Dissociative substitution dissociative mechanism . Negative values for S sup sup indicate that entropy decreases upon achieving the transition state, which often indicates an Associative substitution associative mechanism . Values near zero are difficult to interpret. ref J. H. Espenson Chemical Kinetics and Reaction Mechanism McGraw Hill, 1981, ISBN 0 070019667 2. ref References references Category Chemical kinetics ... more details
Conformational entropy is the entropy associated with the physical arrangement of a polymer chain that assumes a compact or globular protein globular state in solution. The concept is most commonly applied to biological macromolecule s such as protein s and RNA , but can also be used for polysaccharide s and other polymeric organic compound s. To calculate the conformational entropy, the possible conformations assumed by the polymer may first be discretization discretized into a finite number of states, usually characterized by unique combinations of certain structural parameters, each of which has been assigned an energy level. In proteins, backbone dihedral angle s and side chain rotamer s are commonly used as descriptors, and in RNA the base pair ing pattern is used. These characteristics ... mechanics sense of a possible microstate . The conformational entropy associated with a particular .... The entropy of heterogeneous random coil or denaturation biochemistry denatured proteins is significantly ... entropy of the amino acid side chain s in a protein is thought to be a major contributor to the energetic ... Doig Doig AJ, Sternberg MJE. 1995 . Side chain conformational entropy in protein folding. Protein Science 4 2247 51. ref However, a recent study has shown that side chain conformational entropy can ... On Side Chain Conformational Entropy of Proteins. PLoS Comput Biol 2 12 e168. doi 10.1371 journal.pcbi.0020168 ref The conformational entropy of RNA and proteins can be estimated for example, empirical methods to estimate the loss of conformational entropy in a particular side chain on incorporation ... of side chain conformational entropy in protein folding. J Mol Biol 231 3 825 39. ref math S R Sigma ... lowers the conformational entropy of the denatured state and thus increases the energy difference ... 83 1994 . ref References reflist See also Configuration entropy Folding funnel Molten globule Loop entropy Protein folding biochem stub Category Protein structure Category Thermodynamic entropy ... more details
Superherobox image caption character name Entropy alter ego Mr. No One. species Cosmic entities Marvel Comics Cosmic entity publisher Marvel Comics debut creators Peter David br ChrisCross alliances aliases Mr. No One. powers List of comic book superpowers Omnipotence Nigh Omnipotence br br Virtually Unlimited Ability to manipulate, create, or destroy all Matter and Energy at will. br br Omniscience As an abstract concept of the universe . Entropy is a Cosmic entities Marvel Comics Cosmic Entity in the Marvel Comics Marvel Universe Universe who possesses List of comic book superpowers Omnipotence Nigh Omnipotence . A representation of Eternity formed at the beginning of time , whose purpose is to undo, so the cycle of creation and destruction will forever continue. Primarily associated with Genis ... Birth Of EntropyEntropy was created at the beginning of time, possibly when Eternity comics Eternity was formed, Entropy came into being with the seven friendless. Just as all the other friendless have purposes of their own, Entropy s purpose is to destroy, juxtaposed to his father, Eternity, whose purpose entails creation. Entropy and Captain Marvel Entropy and his sister, Epiphany, engineered ... Doon to help him ascertain the cause of his friend s insanity. To prevent Rick from interfering Entropy killed Shinga Doon before he could answer Rick s question. ref Captain Marvel vol 5 2 ref Entropy later meets Genis, revealing he was the son of Eternity comics Eternity . Entropy seeks to destroy ... a paradox resulting in Entropy becoming a new Eternity. The universe is recreated, albeit ... of one of the strongest forces in existence, Entropy has unlimited ability to manipulate space, time, energy and matter on a cosmic scale. Appearance As an abstract concept of the universe, Entropy has no physical form, but Entropy s appearance can vary from lifeform to lifeform, it appears in whatever form that species could perceive him as. References Reflist Marvel Cosmic DEFAULTSORT Entropy ... more details
Unreferenced stub auto yes date December 2009 The entropy of fusion is the increase in entropy when melting a substance. This is almost always positive since the EntropyEntropy as a measure of disorder degree of disorder increases in the phase transition transition from an organized crystal line solid to the disorganized structure of a liquid the only known exception is helium . sfn Atkins Jones 2008 p 236 It is denoted as S sub fus sub and normally expressed in Joule J mole unit mol Kelvin K A natural process such as a phase change will occur when the associated change in the Gibbs free energy is negative. It follows that the entropy of fusion is related to the melting point and the heat of fusion math Delta H fus T fus times Delta S fus math Helium 3 has a negative entropy of fusion at temperatures below 0.3 K. Helium 4 also has a very slightly negative entropy of fusion below 0.8 K. This means that, at appropriate constant pressures, these substances freeze with the addition of heat. sfn Ott Boerio Goates 2000 pp 92 93 Notes Reflist References Citation last Atkins first Peter last2 Jones first2 Loretta year 2008 title Chemical Principles The Quest for Insight edition 4th publisher W. H. Freeman and Company isbn 0 7167 7355 4 page 236 Citation last Ott first J. Bevan last2 Boerio Goates first2 Juliana year 2000 title Chemical Thermodynamics Advanced Applications publisher Academic Press isbn 0 12 530985 6 See also Entropy of vaporization DEFAULTSORT Entropy Of Fusion Category Thermodynamic entropy Category Thermodynamic properties Chem stub ar de Schmelzentropie it Entropia di fusione sv Sm ltentropi ... more details
Infobox album See Wikipedia WikiProject Albums Name Port Entropy Type studio Artist Shugo Tokumaru Cover Released April 21, 2010 Recorded 2009 Genre Indie Pop Length 37 24 Label P Vine Japan Polyvinyl Records Polyvinyl U.S. Producer Shugo Tokumaru No reviews in the infobox, please read Template Infobox album Allmusic Rating 4 5 Allmusic class album id port entropy r2047096 pure url yes link Clash magazine Clash rating 6 10 http www.clashmusic.com reviews shugo tokumaru port entropy link One Thirty BPM 70 http onethirtybpm.com 2010 06 21 album review shugo tokumaru port entropy link Pitchfork Media 6.2 10 http pitchfork.com reviews albums 14792 port entropy link The Skinny magazine The Skinny rating 4 5 http www.theskinny.co.uk article 100774 shugo tokumaru port entropy link sputnikmusic rating 4 5 http www.sputnikmusic.com review 38401 Shugo Tokumaru Port Entropy link Last album Exit Shugo Tokumaru album Exit br 2007 This album Port Entropy br 2010 Port Entropy is the fourth studio album from Japanese multi instrumentalist Shugo Tokumaru . It was released on April 21, 2010 on P Vine Records to generally positive reviews. Track listing Platform 0 44 Tracking Elevator 3 20 Linne 3 51 Lahaha 3 11 Rum Hee 3 46 Laminate 3 59 River Low 2 18 Straw 2 37 Drive thru 3 28 Suisha 3 16 Orange 4 11 Malerina 2 43 External links http www.shugotokumaru.com Shugo Tokumaru http www.polyvinylrecords.com store index.php?id 1553 Port Entropy on Polyvinyl website Category 2010 albums Category Shugo Tokumaru albums Category P Vine Records albums ... more details
Expert subject Cryptography date February 2009 In computing , entropy is the randomness collected by an operating ... or specially provided randomness generators. Entropy in the Linux kernel The Linux kernel generates entropy from Keyboard computing keyboard timings, Mouse computing mouse movements, and Integrated ... Linux kernel patches allowing one to use more entropy sources. ref http www.robot101.net 2005 09 25 missing entropy Robotic Tendencies Missing entropy Bot generated title ref The audio entropyd ... , allows audio data to be used as an entropy source. ref https admin.fedoraproject.org pkgdb packages ... is to use the HAVEGE algorithm through haveged to pool entropy. ref cite web title haveged A simple entropy daemon url http www.issihosts.com haveged accessdate 3 April 2011 ref In some systems, network interrupts can be used as an entropy source as well. ref https linuxlink.timesys.com docs about entropyEntropy and Random Devices LinuxLink by TimeSys Your Embedded Linux Resource Bot generated ... depletes dev random whenever it is being read. ref http www.av8n.com turbid paper turbid.htm High Entropy Randomness Generator Bot generated title ref Entropy in the Hurd kernel A driver ported from the Linux kernel has been made available for the Hurd kernel. ref http ibofobi.dk stuff hurd entropy dev ,u random driver for GNU Hurd ibofobi.dk ref Entropy in Solaris dev random and dev urandom have ... 7d?a view Solaris dev random ref As of Solaris 10, administrators can remove existing entropy ... Entropy in OS 2 There is a software package for OS 2 that allows software processes to retrieve random data. ref http r6.ca RexxEGD Rexx Entropy Gathering Daemon for OS 2 ref Entropy in Windows Microsoft Windows releases newer than 95A feature the CryptoAPI CAPI API that gathers entropy in a similar ... RNG Seed to store a seeded value from all of its entropy sources. ref http www.mail archive.com openssl dev openssl.org msg21829.html Source for entropy on Windows platforms with CryptoAPI installed ... more details
Thermodynamics cTopic Thermodynamic potential Potentials A thermodynamic free entropy is an entropic thermodynamic potential analogous to the thermodynamic free energy free energy . Also known as a Massieu, Planck, or Massieu Planck potentials or functions , or rarely free information. In statistical mechanics, free entropies frequently appear as the logarithm of a Partition function statistical mechanics partition function . In mathematics , free entropy means something quite different it is a generalization of entropy defined in the subject of free probability . A free entropy is generated by a Legendre transform of the entropy. The different potentials correspond to different constraints to which the system may be subjected. Examples see also List of thermodynamic properties The most common examples are class wikitable Name Function Alt. function Natural variables Entropy math S frac 1 T U frac P T V sum i 1 s frac mu i T N i , math align center math U,V, N i , math Massieu potential Helmholtz free entropy math Phi S frac 1 T U math math frac A T math align center math frac 1 T ,V, N i , math Planck potential Gibbs free entropy math Xi Phi frac P T V math math frac G T math align center math frac 1 T , frac P T , N i , math where Col begin Col break math S math is entropy math Phi math is the Massieu potential ref name Planes2000 cite web author Antoni Planes coauthors Eduard Vives date 2000 10 24 publisher Universitat de Barcelona url http www.ecm.ub.es condensed eduard papers massieu node2.html title Entropic variables and Massieu Planck functions accessdate 2007 09 18 ... of the potentials on the natural variables Entropy math S S U,V, N i math By the definition of a total ... Helmholtz free entropy math Phi S frac U T math math Phi frac U T frac P V T sum i 1 s frac mu ... potential Gibbs free entropy math Xi Phi frac P V T math math Xi frac P V T sum i 1 s frac mu i N T frac ... New York isbn 0 471 86256 8 Category Thermodynamic entropy pl Entropia swobodna ... more details
Infobox film name Entropy image Entropy film poster.jpg producer Ashok Amritraj director Phil Joanou writer Phil Joanou starring Stephen Dorff br Judith Godr che br Kelly Macdonald br Lauren Holly br Jon Tenney br Frank Vincent br Paul Guilfoyle br Hector Elizondo br Bray Poor br Kathryn Erbe br Shannon Fiedler br Zach Tyler Eisen credited as Zach Tyler br Jim Gaffigan br Dominic Hawksley cinematography Carolyn Chen editing John Galt distributor Warner Bros. released April 15, 1999 U.S. release runtime 104 min. language English Entropy is a 1999 film directed by Phil Joanou , starring Stephen Dorff and featuring the Irish rock band U2 . The film is largely autobiographical, covering his early film career, his relationships including a very short lived marriage and his pet cat. External links imdb title 0156515 Phil Joanou DEFAULTSORT Entropy Film Category 1999 films indie film stub fr Entropy film ... more details
Loop entropy is the entropy lost upon bringing together two residues of a polymer within a prescribed distance. For a single loop, the entropy varies logarithmically with the number of residues math N math in the loop math Delta S alpha k B ln N , math where math k B math is Boltzmann s constant and math alpha math is a coefficient that depends on the properties of the polymer. This entropy formula corresponds to a power law distribution math P sim N alpha math for the probability of the residues contacting. The loop entropy may also vary with the position of the contacting residues. Residues near the ends of the polymer are more likely to contact quantitatively, have a lower math alpha math than those in the middle i.e., far from the ends , primarily due to excluded volume effects. Wang Uhlenbeck entropy The loop entropy formula becomes more complicated with multiples loops, but may be determined for a Gaussian polymer using a matrix method developed by Wang and Uhlenbeck. Let there be math M math contacts among the residues, which define math M math loops of the polymers. The Wang Uhlenbeck matrix math mathbf W math is an math M times M math symmetric, real matrix whose elements math W ij math equal the number of common residues between loops math i math and math j math . The entropy of making the specified contacts equals math Delta S alpha k B ln det mathbf W math As an example, consider the entropy lost upon making the contacts between residues 26 and 84 and residues 58 and 110 in a polymer cf. ribonuclease A . The first and second loops have lengths 58 84 26 and 52 110 58 , respectively, and they have 26 84 58 residues in common. The corresponding Wang Uhlenbeck matrix is math mathbf W stackrel mathrm def begin bmatrix 58 && 26 26 && 52 end bmatrix math whose determinant is 2340. Taking the logarithm and multiplying by the constants math alpha k B math gives the entropy ... Thermodynamic entropy Category Polymer physics ... more details
Cleanup date February 2008 A work on software engineering by Ivar Jacobson et al. ref Citation first1 Ivar last1 Jacobson first2 Magnus last2 Christerson first3 Patrik last3 Jonsson first4 Gunnar last4 vergaard title Object Oriented Software Engineering A Use Case Driven Approach publisher ACM Press. Addison Wesley year 1992 isbn 0201544350 pages 69 70 ref describes software entropy as follows The second law of thermodynamics , in principle, states that a closed system s randomness disorder cannot be reduced, it can only remain unchanged or increase. A measure of this disorder is entropy . This law also seems plausible for software system s as a system is modified, its disorder, or entropy, always increases. This is known as software entropy Within software development , there are similar theories see Lehman 1985 ref Citation first1 M.M. last1 Lehman first2 L.A. last2 Belady title Program evolution processes of software change publisher Academic Press Professional, Inc., San Diego, CA year 1985 ref , who suggested a number of laws, of which two were, basically, as follows A computer program that is used will be modified When a program is modified, its complexity will increase, provided that one does not actively work against this. end of quote from Jacobson Andrew Hunt and David Thomas use Fixing Broken Windows as a metaphor for avoiding software entropy in software development. ref Citation first1 Andrew last1 Hunt first2 David last2 Thomas title The Pragmatic Programmer publisher Addison Wesley year 1999 isbn 0 201 61622 X Item 4 of 22 tips is Don t Live with Broken Windows . ref The process of code refactoring can result in stepwise reductions in software entropy. See also Software brittleness Software rot References Reflist http www.webopedia.com TERM s software entropy.htm Definition of software entropy on Webopedia Category Software metrics Category Software quality Category Software maintenance hr Softverska entropija ... more details
Unreferenced date December 2009 Residual entropy is small amount of entropy which is present even after a substance is cooled arbitrarily close to absolute zero . It occurs if a material can exist in many different microscopic states when cooled to absolute zero. This can occur if it has many different ground states with exactly the same zero point energy it can also occur if the ground states have slightly different energies, but the system is prevented from finding and settling into the true lowest energy state. It is seen most often in substances which have very weak tendencies to align into their energetic ground state, and or which are cooled quickly. A common example is the case of carbon monoxide , which has a very small Molecular dipole moment dipole moment . As the carbon monoxide crystal is cooled to absolute zero, few of the carbon monoxide molecules have enough time to align themselves ... microstate statistical mechanics microstates , giving a residual entropy of math S Nk ln 2 math , rather than zero. Another example is any amorphous solid glass . These have residual entropy, because ... a macroscopic system. History One of the first examples of residual entropy was pointed out by Linus ... words, entropy. Thus systems that can take multiple configurations at or near absolute zero are said to have residual entropy. Although water ice was the first material for which residual entropy was proposed ... entropy. Geometrical frustration Geometrically frustrated systems in particular often exhibit residual entropy. An important example is spin ice , which is a geometrically frustrated magnetic material ..., thereby producing the same 2 in, 2 out rule as in water ice, and therefore the same residual entropy ... is that the level of residual entropy can be controlled by the application of an external magnetic ... disorder Proton disorder in ice Geometrical frustration DEFAULTSORT Residual Entropy Category Thermodynamic entropy de Nullpunktsentropie it Entropia residua zh classical zh ... more details
In statistics , an approximate entropy ApEn is a technique used to quantify the amount of regularity and the unpredictability of fluctuations over time series data. ref name Pincus1991 cite journal last1 Pinus first1 S. M. last2 Gladstone first2 I. M. last3 Ehrenkranz first3 R. A. title A REGULARITY STATISTIC FOR MEDICAL DATA ANALYSIS journal Journal of Clinical Monitoring and Computing year 1991 volume 7 issue 4 pages 335 345 DOI 10.1007 BF01619355 ref For example, there are two series of data series 1 10,20,10,20,10,20,10,20,10,20,10,20... , which alternates 10 and 20. series 2 10,10,20,10,20,20,20,10,10,20,10,20,20... , which has either a value of 10 or 20, randomly chose, each with probability 1 2. Moment statistics , such as mean and variance , will not distinguish between these two series. Nor will rank order statistics distinguish between these series. Yet series 1 is perfectly regular knowing one term has the value of 20 enables one to predict with certainty that the next term will have the value of 10. Series 2 is randomly valued knowing one term has the value of 20 gives no insight into what value the next term will have. Regularity was originally measured by exact regularity statistics, which has mainly centered around various entropy measures. ref name Pincus1991 ref However, accurate entropy calculation requires vast amounts of data, and the results will be greatly ... entropy as a measure of system complexity journal Proceedings of the National Academy of Sciences ... by modifying an exact regularity statistic, K S entropy . ApEn was initially developed to analyze ... Step 6 math Define approximate entropy math mathrm ApEn math as math mathrm ApEn Phi m r Phi m 1 r ... to determine what quality of true information may be present in the data. Applications ApEn has ... journal last1 Sabeti first1 Malihe title Entropy and complexity measures for EEG signal classification ... using approximate entropy and sample entropy journal American journal of physiology. Heart and circulatory ... more details
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