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101.
We study a discrete dynamical system whose evolution is governed by rules similar to those of Conway's game of Life but also include a stochastic element (parametrized by a temperature). Statistical properties that are examined are density as a function of temperature and entropy (suitably defined). A phase transition and a certain thermodynamic constant of the motion are observed.Lady Davis Visiting Scientist at the Technion 1974–75. 相似文献
102.
Michael Aizenman FranÇois Delyon Bernard Souillard 《Journal of statistical physics》1980,23(3):267-280
We rigorously prove that the probabilityP
n
that the origin of ad-dimensional lattice belongs to a cluster of exactlyn sites satisfiesP
n
> exp(–n
(d–1)/d
) whenever percolation occurs. This holds for the usual (noninteracting) percolation models for any concentrationp > p
c
, as well as for the equilibrium states of lattice spin systems with quite general interactions. Such a lower bound applies also if no percolation occurs, but if it appears in some other phase of the system. 相似文献
103.
104.
C. I. J. M. Stuart 《Foundations of Physics Letters》1991,4(5):479-492
Aprediction puzzle leads to a form ofnecessary realism which forces the rejection of a central tenet of the Copenhagen interpretation. This leads to reconsidering conceptual difficulties related to Bell's locality premise. It is shown that aparadox of elementary probability theory puts new light on Bell's assumption that causality and statistical independence are mutually incompatible.
Nemo dat quod non habet : No one can offer more than he has ability to give; in that spirit, this paper is dedicated to the memory of J.S. Bell. 相似文献
105.
Walter Wyss 《Foundations of Physics Letters》1991,4(3):235-246
Fractional noiseN(t),t 0, is a stochastic process for every , and is defined as the fractional derivative or fractional integral of white noise. For = 1 we recover Brownian motion and for = 1/2 we findf
–1-noise. For 1/2 1, a superposition of fractional noise is related to the fractional diffusion equation. 相似文献
106.
The paper describes the structure of a new space of generalized Wiener functionals,
, called the Wiener algebra, or space of Wiener distributions, and demonstrates its use in the white noise analysis. The concepts of derivatives and integrals for multi-time parameter generalized stochastic process:N
are introduced, and a derivative version of Itô's lemma is proved. The algebraic structure of
and its lattice of subspaces is elaborated, and within this framework a generalized version of the Malliavin calculus is presented. 相似文献
107.
A. Žilinskas 《Journal of Global Optimization》1992,2(2):145-153
A review of statistical models for global optimization is presented. Rationality of the search for a global minimum is formulated axiomatically and the features of the corresponding algorithm are derived from the axioms. Furthermore the results of some applications of the proposed algorithm are presented and the perspectives of the approach are discussed. 相似文献
108.
K. Marti 《Mathematical Methods of Operations Research》1992,36(3):259-294
In engineering and economics often a certain vectorx of inputs or decisions must be chosen, subject to some constraints, such that the expected costs (or loss) arising from the deviation between the outputA() x of a stochastic linear systemxA()x and a desired stochastic target vectorb() are minimal. Hence, one has the following stochastic linear optimization problem minimizeF(x)=Eu(A()x b()) s.t.xD, (1) whereu is a convex loss function on
m
, (A(), b()) is a random (m,n + 1)-matrix, E denotes the expectation operator andD is a convex subset of
n
. Concrete problems of this type are e.g. stochastic linear programs with recourse, error minimization and optimal design problems, acid rain abatement methods, problems in scenario analysis and non-least square regression analysis.Solving (1), the loss functionu should be exactly known. However, in practice mostly there is some uncertainty in assigning appropriate penalty costs to the deviation between the outputA ()x and the targetb(). For finding in this situation solutions hedging against uncertainty a set of so-called efficient points of (1) is defined and a numerical procedure for determining these compromise solutions is derived. Several applications are discussed. 相似文献
109.
We study the Boltzmann-Grad limit in various versions of the two-dimensional HPP cellular automaton. In the completely deterministic case we prove convergence to an evolution that is not of kinetic type, a well-known phenomenon after Uchyiama's paper on the Broadwell gas, whereas the limiting equation becomes of kinetic type in the model with random collisions. The main part of the paper concerns the case where the collisions are deterministic and the randomness comes from inserting, between any two successive HPP updatings,
- stirring updatings, <1 being any fixed positive number and a parameter which tends to 0. The initial measure is a product measure with average occupation numbers of the order of (low-density limit) and varying on distances of the order of –1. The limit as 0 of the system evolved for times of the order of
-1- corresponds to the Boltzmann-Grad limit. We prove propagation of chaos and that the renormalized average occupation numbers (i.e., divided by) converge to the solution of the Broadwell equation. Convergence is proven at all times for which the solution of the Broadwell equation is bounded. 相似文献
110.
Stochastic detection of motor protein-RNA complexes by single-channel current recording. 总被引:1,自引:0,他引:1
Yann Astier Denis E Kainov Hagan Bayley Roman Tuma Stefan Howorka 《Chemphyschem》2007,8(15):2189-2194
A label- and immobilization-free approach to detecting the reversible formation of complexes between nucleic acids and proteins at the single-molecule level is described. The voltage-driven translocation of individual oligoribonucleotides through a nanoscale protein pore is observed by single-channel current recordings. The oligoribonucleotide 5'-C25A(25)-3' gives rise to current blockades with an average duration of approximately 0.5 ms. In the presence of the RNA-binding ATPase P4, a viral packaging motor from bacteriophage phi8, longer events of tens to hundreds of milliseconds are observed. Upon addition of ATP the long events disappear, indicating the dissociation of the P4RNA complex. The frequency of events also depends on the concentration of P4 and the length of the oligoribonucleotide, thereby confirming the specificity of the P4RNA events. This study shows that single-channel current recordings can be used to monitor RNA-protein complex formation, thus opening up a new means to examine the motor activity of RNA- or DNA-processing enzymes. 相似文献