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51.
A. Hansen M.H. Jensen K. Sneppen G. Zocchi 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,6(1):157-161
We present a statistical mechanics treatment of the stability of globular proteins which takes explicitly into account the
coupling between the protein and water degrees of freedom. This allows us to describe both the cold and the warm unfolding,
thus qualitatively reproducing the known thermodynamics of proteins.
Received: 19 March 1998 / Revised and Accepted: 25 May 1998 相似文献
52.
Perfect information two-person zero-sum markov games with imprecise transition probabilities 总被引:1,自引:0,他引:1
Hyeong Soo Chang 《Mathematical Methods of Operations Research》2006,64(2):335-351
Based on an extension of the controlled Markov set-chain model by Kurano et al. (in J Appl Prob 35:293–302, 1998) into competitive two-player game setting, we provide a model of perfect information two-person zero-sum Markov games with imprecise transition probabilities. We define an equilibrium value for the games formulated with the model in terms of a partial order and then establish the existence of an equilibrium policy pair that achieves the equilibrium value. We further analyze finite-approximation error bounds obtained from a value iteration-type algorithm and discuss some applications of the model. 相似文献
53.
本文第一部分主要把扭曲的方法运用到模上,从而得到扭曲模.作为特例,我们构造了H M的Smaush模和量子模.当K是有限维Hopf代数,证明K* M是一个右D(K)-Hopf模,因此得到了一个基本同构定理.第二部分主要把斜余配对双代数进行推广,得到了斜余配对Hopf模,并且给出判断斜余配对Hopf模的一个充要条件. 相似文献
54.
This paper newly designs the recursive least-squares (RLS) fixed-lag smoother and filter using the covariance information in linear continuous-time stochastic systems. It is assumed that the signal is observed with additive white observation noise and the signal is uncorrelated with the observation noise. The estimators require the covariance information of the signal and the variance of the observation noise. The auto-covariance function of the signal is expressed in the semi-degenerate kernel form. 相似文献
55.
LB膜中螺吡喃材料的光学性质研究 总被引:1,自引:0,他引:1
利用LB技术制备螺吡喃有序分子膜,研究了气液界面上螺吡喃材料在不同成份和不同pH值亚相时的成膜行为,着重研究了螺吡喃在LB膜这个特殊介质环境中不同于溶液的光致变色机理和光学性质 相似文献
56.
Quadratically constrained minimum cross-entropy analysis 总被引:3,自引:0,他引:3
Quadratically constrained minimum cross-entropy problem has recently been studied by Zhang and Brockett through an elaborately constructed dual. In this paper, we take a geometric programming approach to analyze this problem. Unlike Zhang and Brockett, we separate the probability constraint from general quadratic constraints and use two simple geometric inequalities to derive its dual problem. Furthermore, by using the dual perturbation method, we directly prove the strong duality theorem and derive a dual-to-primal conversion formula. As a by-product, the perturbation proof gives us insights to develop a computation procedure that avoids dual non-differentiability and allows us to use a general purpose optimizer to find an-optimal solution for the quadratically constrained minimum cross-entropy analysis. 相似文献
57.
为了探讨有机化合物的分子结构与理化性质的关系,作者在以前的工作基础上,基于一阶分子连通性拓扑指数构建了一个信息拓扑指数.将拓扑指数与取代脂环烃系列分子的气态标准生成热、气态标准熵、气态标准生成自由能、沸点、临界温度、临界压力、临界体积、汽化热、密度、热容及表面张力等十一种热力学性质及物理化学性质相关联,用一个通用公式对各类性质进行概括,然后用已有的实验数据与拓扑指数进行回归分析,得到一系列计算各性质的经验公式.回归结果发现,分子的理化性质与拓扑指数有较好的相关性,有5类性质的复相关系数大于0.99.用经验公式对各类性质进行重新计算,其结果与实验值比较符合,用实验值对计算值作图,发现各数据点紧靠对角线,说明误差较小.残差分布呈正态分布. 相似文献
58.
This is a sequel to Part I of A Subjective Bayesian Approach to the Theory of Queues. The focus here is on inference and a use of Shannon's measure of information for assessing the amount of information conveyed by the various types of data from queues. The notation and terminology used here is established in Part I. 相似文献
59.
Let G be a simple graph with adjacency matrix A(G) and (G,x) the permanental polynomial of G. Let G × H denotes the Cartesian product of graphs G and H. Inspired by Kleins idea to compute the permanent of some matrices (Mol. Phy. 31 (3) (1976) 811–823), in this paper in terms of some orientation of graphs we study the permanental polynomial of a type of graphs. Here are some of our main results.1.If G is a bipartite graph containing no subgraph which is an even subdivision of K
2,3, then G has an orientation G
e such that (G,x) = det (xI-A(G
e
)), where A(G
e
) denotes the skew adjacency matrix of G
e.2.Let G be a 2-connected outerplanar bipartite graph with n vertices. Then there exists a 2-connected outerplanar bipartite graph
with 2n+2 vertices such that (G,x) is a factor of
.3.Let T be an arbitrary tree with n vertices. Then
, where
1
,
2
, ...,
n are the eigenvalues of T. 相似文献
60.
The nickel(1) complex, Ni(teta)+, formed by cathodic reduction of the corresponding nickel(11) complex, reacts rapidly with alkyl bromides to form an unstable intermediate containing a nickelcarbon bond. When the electrolysis medium also contains an activated olefin an insertion reaction occurs. The new metalcarbon bond is cleaved by further reduction and overall the reduction of Ni(teta)2+ in the presence of RBr and CH2CHY leads to high yiels of RCH2CH2Y. 相似文献