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261.
组成系统哈密顿量的一组算子对易关系封闭,构成一个李代数.这组算子的统计平均值随时间的演化满足一个封闭的一阶线性微分方程组.讨论了有关物理量的统计平均值随时间的变化关系. 相似文献
262.
本文给出了累积和控制图(CUSUM)监测稳定过程均值漂移的平均运行长度(ARL)的区间估计,并采用数字模拟的方法对CUSUM,GLR,GEWMA以及RFCuscore四种控制图监测稳定过程均值漂移的效果进行比较,结果显示CUSUM效果最好. 相似文献
263.
Games with frequency-dependent stage payoffs (FD-games), are infinitely repeated non-cooperative games played at discrete moments in time called stages. The stage payoffs depend on the action pair actually chosen, and on the relative frequencies with which all actions were chosen before.
We assume that players wish to maximize their expected (limiting) average rewards over the entire time-horizon. We prove an analogy to, as well as an extension of the (perfect) Folk Theorem. Each pair of rewards in the convex hull of all individually-rational jointly-convergent pure-strategy rewards can be supported by an equilibrium. Moreover, each pair of rewards in same set giving each player strictly more than the threat-point-reward, can be supported by a subgame-perfect equilibrium. Under a pair of jointly-convergent strategies, the relative frequency of each action pair converges in the long run.
Received: March 2002/Revised: January 2003 相似文献
264.
Hyeong Soo Chang 《Journal of Mathematical Analysis and Applications》2003,286(2):636-651
We consider an approximation scheme for solving Markov decision processes (MDPs) with countable state space, finite action space, and bounded rewards that uses an approximate solution of a fixed finite-horizon sub-MDP of a given infinite-horizon MDP to create a stationary policy, which we call “approximate receding horizon control.” We first analyze the performance of the approximate receding horizon control for infinite-horizon average reward under an ergodicity assumption, which also generalizes the result obtained by White (J. Oper. Res. Soc. 33 (1982) 253-259). We then study two examples of the approximate receding horizon control via lower bounds to the exact solution to the sub-MDP. The first control policy is based on a finite-horizon approximation of Howard's policy improvement of a single policy and the second policy is based on a generalization of the single policy improvement for multiple policies. Along the study, we also provide a simple alternative proof on the policy improvement for countable state space. We finally discuss practical implementations of these schemes via simulation. 相似文献
265.
266.
Minvydas Ragulskis Rimas Maskeliunas Liutauras Ragulskis Vytautas Turla 《Optics and Lasers in Engineering》2005,43(9):3640
Geometric moiré fringe formation method is a classical well-established experimental technique with numerous practical applications. This paper proposes the application of time-average geometric moiré analysis for the determination of dynamic displacements of the lithographic press rubber roller. This optical measurement technique is a natural extension of double-exposure geometric moiré for the identification of dynamic displacements of vibrating elastic structures. Experimental investigations prove the validity and effective practical applicability of the method. 相似文献
267.
??A single distribution-free (nonparametric) Phase II exponentially weighted moving average (EWMA) chart based on the Cucconi statistic, referred to as the EWMA-Cucconi (EC) chart, is considered here for simultaneously monitoring shifts in the unknown location and scale parameters of a univariate continuous process. A comparison with some other existing nonparametric EWMA charts is presented in terms of the average, the standard deviation and some
percentiles of the run length distribution. Numerical results based on Monte Carlo analysis show that the EC chart provides quite a satisfactory performance. The effect of the Phase I (reference) sample size on the IC performance of the EC chart is studied in detail. The application of the EC chart is illustrated by two real data examples. 相似文献
268.
A. Yu. Khrennikov 《Theoretical and Mathematical Physics》2007,152(2):1111-1121
We show that in contrast to a rather common opinion, quantum mechanics can be represented as an approximation of classical
statistical mechanics. We consider an approximation based on the ordinary Taylor expansion of physical variables. The quantum
contribution is given by the second-order term. To escape technical difficulties related to the infinite dimensionality of
the phase space for quantum mechanics, we consider finite-dimensional quantum mechanics. On one hand, this is a simple example
with high pedagogical value. On the other hand, quantum information operates in a finite-dimensional state space. Therefore,
our investigation can be considered a construction of a classical statistical model for quantum information.
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 2, pp. 278–291, August, 2007. 相似文献
269.
A new quintic equation of state (EOS) for pure substances and mixtures is proposed. The equation is based on critical parameters and one saturation point. The proposed Q5EOS is a generalisation of many cubic equations of state. Equation Q5 has five parameters, four of which are temperature-independent. The temperature-dependent parameter a is expressed by a relation based on a simple power function. Parameters defining this function can be calculated from saturation data, Boyle temperature and supercritical data. 相似文献
270.
Performance Optimization of Phase-Shifting Interferometry Using Data Average on Wide Range Roughness Measurement 总被引:1,自引:0,他引:1
Min-Sik Jo 《Optical Review》2004,11(1):55-59
Performance optimization of phase-shifting interferometry was investigated using data average on wide range roughness measurement. The interferometry performance was strongly affected by data average and an optimal data averaging condition of minimal measurement error was found. The high limit roughness level which makes the data average available for the interferometry performance optimization providing a reproducible and smallest roughness was determined to be about 5 _A rms roughness. Therefore, the optimal interferometry performance absolutely required data average for finer surfaces than about 5 _A rms roughness. On the other hand, the optimal interferometry performance for surfaces rougher than about 10 _A rms required little data average. The reliability of the optimal performance of phaseshifting interferometry was checked. 相似文献