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31.
LW15-252型SF_6断路器存在的问题和对策 总被引:1,自引:1,他引:0
国产SF6断路器已在电力系统中得到了广泛的应用,随着时间的推移,这种断路器存在的问题也逐渐地暴露出来。笔者介绍了LW15-252型SF6断路器在实际运用中存在的问题和采取的对策。 相似文献
32.
The objective of this note is to propose a method for stabilization of structurally fixed modes in expansions of LTI dynamic systems in the scope of overlapping decentralized control design based on the expansion/contraction framework, enabling successful design for a broader class of problems than considered so far. The method is based on a judicious choice of complementary matrices in the expanded space. Numerical examples are provided to illustrate simplicity and efficiency of the proposed approach. 相似文献
33.
A method is considered to solve a conditional optimization problem with a linear-fractional objective function over permutations.
The performance of sub algorithms to solve this problem is evaluated. The practical efficiency of the algorithm is analyzed
by conducting numerical experiments.
__________
Translated from Kibernetika i Sistemnyi Analiz, No. 4, pp. 133–146, July–August 2007. 相似文献
34.
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
35.
Many problems consist in splitting a set of objects into different groups so that each group verifies some properties. In practice, a partitioning is often encoded by an array mapping each object to its group numbering. In fact, the group number of an object does not really matter, and one can simply rename each group to obtain a new encoding. That is what we call the symmetry of the search space in a partitioning problem. This property may be prejudicial for optimization methods such as evolutionary algorithms (EA) which require some diversity during the search. 相似文献
36.
The authors report a meta-analysis of age differences in everyday problem-solving/decision-making effectiveness (EPSE). Effect sizes were calculated to reflect 3 age group comparisons: old versus young, young versus middle-aged, and middle-aged versus old. Findings from the meta-analysis of 28 separate studies with an aggregate of 4,482 participants do not support theories of preserved EPSE in late adulthood. Although significant age differences of moderate magnitude persisted across methodological and theoretical domains, rating criteria (experimenter vs. participant) emerged as a significant moderator of the effect magnitude and direction. In addition, EPSE in older adults was bolstered when problem content was interpersonal and when samples were highly educated. Finally, the current results support the conceptual integration of findings from the everyday problem-solving and everyday decision-making literatures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
37.
This note presents a stabilizing decentralized model predictive control (MPC) algorithm for nonlinear discrete time systems. No information is assumed to be exchanged between local control laws. The stability proof relies on the inclusion of a contractive constraint in the formulation of the MPC problem. 相似文献
38.
The present paper studies a feedback regulation problem that arises in at least two different biological applications. The feedback regulation problem under consideration may be interpreted as an adaptive control problem for tuning bifurcation parameters, and it has not been studied in the control literature. The goal of the paper is to formulate this problem and to present some preliminary results. 相似文献
39.
Garth Isaak 《Information Processing Letters》2004,92(3):107-111
Given a tournament with an acyclic tournament as a feedback arc set we give necessary and sufficient conditions for this feedback arc set to have minimum size. 相似文献
40.