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Energy spectra for decaying 2D turbulence in a bounded domain 总被引:1,自引:0,他引:1
We use results derived in the framework of the replica approach to study the liquid-glass thermodynamic transition. The main results are derived without using replicas and applied to the study of the Lennard-Jones binary mixture introduced by Kob and Andersen. We find that there is a phase transition due to the entropy crisis. We compute both analytically and numerically the value of the phase transition point T(K) and the specific heat in the low temperature phase. 相似文献
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H. C. P. Berbee C. G. E. Boender A. H. G. Rinnooy Ran C. L. Scheffer R. L. Smith J. Telgen 《Mathematical Programming》1987,37(2):184-207
Two probabilistic hit-and-run algorithms are presented to detect nonredundant constraints in a full dimensional system of
linear inequalities. The algorithms proceed by generating a random sequence of interior points whose limiting distribution
is uniform, and by searching for a nonredundant constraint in the direction of a random vector from each point in the sequence.
In the hypersphere directions algorithm the direction vector is drawn from a uniform distribution on a hypersphere. In the
computationally superior coordinate directions algorithm a search is carried out along one of the coordinate vectors. The
algorithms are terminated through the use of a Bayesian stopping rule. Computational experience with the algorithms and the
stopping rule will be reported. 相似文献
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C. G. E. Boender A. H. G. Rinnooy Kan G. T. Timmer L. Stougie 《Mathematical Programming》1982,22(1):125-140
A stochastic method for global optimization is described and evaluated. The method involves a combination of sampling, clustering and local search, and terminates with a range of confidence intervals on the value of the global optimum. Computational results on standard test functions are included as well. 相似文献
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PC. M. Gubbens G. J. Boender A. M. van der Kraan K. H. J. Buschow 《Hyperfine Interactions》1992,68(1-4):329-332
DyFe12?xMx (M=Si,Ti,Cr) were studied with57Fe and161Dy Mössbauer spectroscopy. The deduced coupling constants JRFe of these compounds are about equal. It is found that Si is substituting one particular Fe-site, while Cr is substituting Fe randomly. In DyFe10Si2 two Fe-sites favour a c-axis anisotropy, while the third one favours the basal plane. 相似文献
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A pulse scheme for phase sensitive detection of two-dimensional (2D) homonuclear correlation magic angle spinning (MAS) NMR spectra is proposed. This scheme combines the time proportional phase increment phase cycling scheme and the time reversal 2D MAS experiment. This approach enables the direct detection of purely absorptive 2D MAS spectra, containing cross peaks that connect only diagonal peaks of dipolar correlated spins. 相似文献
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Suppose a sequential sample is taken from an unknown discrete probability distribution on an unknown range of integers, in an effort to sample its maximum. A crucial issue is an appropriate stopping rude determining when to terminate the sampling process. We approach this problem from a Bayesian perspective, and derive stopping rules that minimize loss functions which assign a loss to the sample size and to the deviation between the maximum in the sample and the true (unknown) maximum. We will show that our rules offer an extremely simple approximate solution to the well-known problem to terminate the Multistart method for continuous global optimization. 相似文献
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By far the most efficient methods for global optimization are based on starting a local optimization routine from an appropriate
subset of uniformly distributed starting points. As the number of local optima is frequently unknown in advance, it is a crucial
problem when to stop the sequence of sampling and searching. By viewing a set of observed minima as a sample from a generalized
multinomial distribution whose cells correspond to the local optima of the objective function, we obtain the posterior distribution
of the number of local optima and of the relative size of their regions of attraction. This information is used to construct
sequential Bayesian stopping rules which find the optimal trade off between reliability and computational effort. 相似文献
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