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71.
72.
The error of solution of Cauchy problems for systems of ordinary differential equations is estimated in the case where the
input data are approximate. It is shown how to prepare a program for computing the right-hand sides of the system automatically
and simultaneously. Diagrams are presented to illustrate the efficiency of parallelization.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 175–182, March–April 2007. 相似文献
73.
74.
Shu‐Li Sun Jing Ma Nan Lv 《International Journal of Adaptive Control and Signal Processing》2008,22(10):932-948
Based on the optimal fusion estimation algorithm weighted by scalars in the linear minimum variance sense, a distributed optimal fusion Kalman filter weighted by scalars is presented for discrete‐time stochastic singular systems with multiple sensors and correlated noises. A cross‐covariance matrix of filtering errors between any two sensors is derived. When the noise statistical information is unknown, a distributed identification approach is presented based on correlation functions and the weighted average method. Further, a distributed self‐tuning fusion filter is given, which includes two stage fusions where the first‐stage fusion is used to identify the noise covariance and the second‐stage fusion is used to obtain the fusion state filter. A simulation verifies the effectiveness of the proposed algorithm. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
75.
岩电实验饱和度模型在探明储量中的应用 总被引:5,自引:2,他引:3
合油饱和度是评价砂岩油气层最主要的参数。确定合油饱和度的方法较多,确定储层原始合油饱和度的方法主要有直接法和间接法,直接法是指应用密闭取心或油基泥浆取心井获得的资料,通过实验室分析直接获得原始合油饱和度的方法;间接法是指应用测井曲线、毛管压力曲线、类比等资料间接获得原始含油饱和度。阿尔奇公式是测井定量解释饱和度的理论基础。在实验室条件下,通过作模拟地层条件下的岩电实验,取得地层的真电阻率,对深侧向视电阻率进行厚度校正,建立正确的饱和度解释模型,使岩电实验所建立的饱和度模型在探明储量中得到了广泛的应用。 相似文献
76.
A task-switching paradigm with a 2:1 mapping between cues and tasks was used to separate cue-switching processes (indexed through pure cue-switch costs) from actual task-switching processes (indexed through additional costs in case of cue and task changes). A large portion of total switch costs was due to cue changes (Experiments 1 and 2), and cue-switch costs but not task-switch costs were sensitive to effects of practice (Experiment 1) and preparation (Experiment 2). In contrast, task-switch costs were particularly sensitive to response-priming effects (Experiments 1 and 2) and task-set inhibition (Experiment 3). Results suggest two processing stages relevant during task-set selection: cue-driven retrieval of task rules from long-term memory and the automatic application of rules to a particular stimulus situation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
In this paper the response of nonlinear systems driven by parametric Poissonian white noise is examined.As is well known, the response sample function or the response statistics of a system driven by external white noise processes is completely defined. Starting from the system driven by external white noise processes, when an invertible nonlinear transformation is applied, the transformed system in the new state variable is driven by a parametric type excitation. So this latter artificial system may be used as a tool to find out the proper solution to solve systems driven by parametric white noises. In fact, solving this new system, being the nonlinear transformation invertible, we must pass from the solution of the artificial system (driven by parametric noise) to that of the original one (driven by external noise, that is known). Moreover, introducing this invertible nonlinear transformation into the Itô’s rule for the original system driven by external input, one can derive the Itô’s rule for systems driven by a parametric type excitation, directly. In this latter case one can see how natural is the presence of the Wong–Zakai correction term or the presence of the hierarchy of correction terms in the case of normal and Poissonian white noise, respectively. Direct transformation on the Fokker–Planck and on the Kolmogorov–Feller equation for the case of parametric input are found. 相似文献
78.
79.
The results are given of numerical solution of the Boltzmann equation in a binomial approximation in view of elastic and inelastic electron collisions in Xe+CH4 mixtures and in pure methane. The electron energy distribution functions obtained are used to calculate the electron transport coefficients for E/N values of up to several Townsends, i.e., the drift velocity, mobility, average and characteristic energies, diffusion coefficient. The results of calculation for pure methane fit the available experimental data. A similarity rule is found for the electron transport coefficients in a Xe+CH4 mixture with different concentrations of methane molecules, which enables one to determine the values of transport coefficients in a mixture with a minor (less than 30 percents) methane content. 相似文献
80.