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Evolution of Density-Dependent Cooperation
Bulletin of Mathematical Biology, 2014Cooperation is surprisingly common in life despite of its vulnerability to selfish cheating, i.e. defecting. Defectors do not contribute to common resources but take the advantage of cooperators' investments. Therefore, the emergence and maintenance of cooperation have been considered irrational phenomena.
Seppänen, A., Parvinen, K.
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2006 IEEE Information Theory Workshop, 2006
Density evolution for LDPC codes predicts asymptotic performance and serves as a practical design tool for designing top performing structures [1]. Many papers advocate the use of exit chart methods and other approximations, proclaiming that density evolution is computationally too intensive.
Hui Jin, Tom Richardson 0001
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Density evolution for LDPC codes predicts asymptotic performance and serves as a practical design tool for designing top performing structures [1]. Many papers advocate the use of exit chart methods and other approximations, proclaiming that density evolution is computationally too intensive.
Hui Jin, Tom Richardson 0001
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Density Matrices and Their Time Evolution
Open Systems & Information Dynamics, 2008Already in the case of finite dimensional Hilbert spaces [Formula: see text] the general form of density matrices ρ is not known. The main reason for this lack of knowledge is the nonlinear constraint for these matrices. We propose a representation of density matrices on finite dimensional Hilbert spaces in terms of finitely many independent ...
Erwin Brüning, Francesco Petruccione
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Microstructure evolution in density relaxation by tapping
Physical Review E, 2010The density relaxation phenomenon is modeled using both Monte Carlo and discrete element simulations to investigate the effects of regular taps applied to a vessel having a planar floor filled with monodisperse spheres. Results suggest the existence of a critical tap intensity which produces a maximum bulk solids fraction.
Anthony D, Rosato +4 more
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Evolution of the cosmic density matrix
Physical Review D, 1989The dynamics of a reduced cosmic density matrix for minisuperspace is derived by projecting out inhomogeneous modes. This projection procedure roughly represents the intrinsic loss of information beyond the horizon of the local observer. Even if the wave function of the whole Universe exists, it will be unobservable and therefore should be projected ...
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Evolution of the density parameter in multidimensional cosmology
Physical Review D, 1993Inflation as a dynamical effect of extra dimensions is discussed from the viewpoint of the evolution of the parameters Ω and q in the physical space. By reducing the dynamics of the models FLRW (k=±1)×T D (T D =S 1 ×... ×S 1 ) and FLRW (k=0)×S D , where FLRW denotes Friedmann, Lemaitre, Robertson, and Walker, to two dimensions it is shown that ...
, Szydlowski, , Heller, , Lapeta
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Density Evolution for Expectation Propagation
2007 IEEE International Conference on Acoustics, Speech and Signal Processing - ICASSP '07, 2007Expectation propagation (EP) is a theoretical extension of the belief propagation family of message passing algorithms for statistical inference which allows for efficient handling of models with continuous random variables as well as second or higher order correlation via the use of standard exponential families of probability measures.
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Space density evolution of quasars
Nature, 1978ATTEMPTS to obtain interesting cosmological information from the study of quasars have been thwarted by the apparent large spread in quasar luminosities so that the conventional Hubble plot produces a scatter diagram1. Several authors2–4 have used an absolute magnitude–redshift diagram to provide a standard candle and hence improved the Hubble diagram.
N. J. STEWART, M. R. S. HAWKINS
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On the Conditional Density of a Noise Driven Evolution
ZAMM - Journal of Applied Mathematics and Mechanics / Zeitschrift für Angewandte Mathematik und Mechanik, 1976AbstractThe purpose of this brief note is to establish a method for the determination of the conditional probability density of a linear distributed parameter evolution process driven by Gaussian noisy sources. A semi‐group theoretic inversion of the evolution operator is used. Certain estimates for the confinement probability functional are obtained.
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Host density and the evolution of parasite virulence
Journal of Theoretical Biology, 1989Social and cultural habits of human populations affect the biological evolution of the agents of infectious diseases. Measles and similar diseases have evolved in the Old World and cannot have existed in their present form before the rise of the great river valley civilizations.
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