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991.
男上体运动变形与服装放松量的关系 总被引:2,自引:0,他引:2
对东北地区男青年体型进行了测量 ,建立了东北地区男青年人体模型。并选若干标准人体采用剪切变形法对男上装显著变形部位的变化方向及变化量进行了研究分析 ,得到男上装各主要部位适合人体正常运动所需的服装放松量。 相似文献
992.
随机模糊神经网络及在随机混沌时间序列预测中的应用 总被引:1,自引:0,他引:1
针对随机模糊神经网络(SFNN)的网络结构没有明确的物理含义,仅仅是一种实现随机模糊逻辑系统的计算结构的问题,对其网络结构进行了改进,重新定义了每层的节点原型。改进后每层之间的物理含义明确且节点数目减少,从而计算量有所减少。对于SFNN的参数和结构,可以分别通过参数学习算法和结构学习算法来优化。将SFNN用于随机混沌时间序列预测,仿真结果表明:该系统由于引入了随机的概念,使网络能更有效地防止噪声的干扰,因而更适合于工程应用。 相似文献
993.
We discuss the dissipative dynamics of a classical particle coupled to an infinitely extended heat reservoir. We announce a number of results concerning the ergodic properties of this model. The novelty of our approach is that it extends beyond Markovian dynamics to the case where the Langevin equation is driven by colored noise. Our method works in arbitrary space dimension, and for fully nonlinear systems. 相似文献
994.
The evolution and the steady-state structure of gasdynamic disturbances in a thermodynamically nonequilibrium gas are investigated both analytically and numerically. It is shown that in a medium with negative viscosity steady-state structures different from those in an equilibrium medium can exist. The conditions of existence of stationary shock waves with a discontinuous front and a smooth increase or decrease in the amplitude behind the front, waves with an oscillatory structure, and a stationary self-wave pulse with a power-law trailing front are determined.Translated from Izvestiya Rossiiskoi Academii Nauk, Mekhanika Zhidkosti i Gaza, No. 5, 2004, pp. 181–191. Original Russian Text Copyright © 2004 by Makaryan and Molevich. 相似文献
995.
996.
An aspiration based simulated annealing algorithm for continuousvariables has been proposed. The new algorithm is similar to the one givenby Dekkers and Aarts (1991) except that a kind of memory is introduced intothe procedure with a self-regulatory mechanism. The algorithm has beenapplied to a set of standard global optimization problems and a number ofmore difficult, complex, practical problems and its performance comparedwith that of the algorithm of Dekkers and Aarts (1991). The new algorithmappears to offer a useful alternative to some of the currently availablestochastic algorithms for global optimization. 相似文献
997.
Let Φ′ be the strong dual of a nuclear Fréchet space Φ. In this paper we present regularity properties, weak convergence, and convergence in probability and in mean square of Φ′-valued stochastic evolution equations and convolutions with respect to Φ′-valued cadlag martingales. 相似文献
998.
本文研究了随机需求下随机利润的分布类型,给出了随机需求为连续型随机变量时,随机利润为连续型随机变量的充分必要条件,生动而有趣地回答了本文提出的问题。 相似文献
999.
R. Xu Y.J. Yan O. Kühn 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2002,19(3):293-305
Separating multidimensional problems into that of a relevant system which is coupled to a bath of harmonic oscillators is
a common concept in condensed phase theory. Focusing on the specific problem of intramolecular proton transfer in an isolated
tropolone derivative, we consider the reactive proton moving in the plane of the molecule as the system and the remaining
substrate normal modes as the bath. An all-Cartesian system-plus-substrate Hamiltonian is constructed employing density functional
theory. It is then used to determine the temperature-dependent effective reduced reaction Hamiltonian and the state-to-state
dissipation rates induced via the system-substrate coupling up to the bi-quadratic order. The important substrate modes for the T1-relaxation and the pure T2-dephasing rates, which are either intra- or inter-well in nature, are identified numerically and analyzed physically with
molecular details.
Received 19 November 2001 and Received in final form 19 February 2002 相似文献
1000.
In this paper we are interested in the effect that dependencies in the arrival process to a queue have on queueing properties such as mean queue length and mean waiting time. We start with a review of the well known relations used to compare random variables and random vectors, e.g., stochastic orderings, stochastic increasing convexity, and strong stochastic increasing concavity. These relations and others are used to compare interarrival times in Markov renewal processes first in the case where the interarrival time distributions depend only on the current state in the underlying Markov chain and then in the general case where these interarrivai times depend on both the current state and the next state in that chain. These results are used to study a problem previously considered by Patuwo et al. [14].Then, in order to keep the marginal distributions of the interarrivai times constant, we build a particular transition matrix for the underlying Markov chain depending on a single parameter,p. This Markov renewal process is used in the Patuwo et al. [14] problem so as to investigate the behavior of the mean queue length and mean waiting time on a correlation measure depending only onp. As constructed, the interarrival time distributions do not depend onp so that the effects we find depend only on correlation in the arrival process.As a result of this latter construction, we find that the mean queue length is always larger in the case where correlations are non-zero than they are in the more usual case of renewal arrivals (i.e., where the correlations are zero). The implications of our results are clear. 相似文献