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41.
A parallel inexact Newton method with a line search is proposed for two-stage quadratic stochastic programs with recourse. A lattice rule is used for the numerical evaluation of multi-dimensional integrals, and a parallel iterative method is used to solve the quadratic programming subproblems. Although the objective only has a locally Lipschitz gradient, global convergence and local superlinear convergence of the method are established. Furthermore, the method provides an error estimate which does not require much extra computation. The performance of the method is illustrated on a CM5 parallel computer.This work was supported by the Australian Research Council and the numerical experiments were done on the Sydney Regional Centre for Parallel Computing CM5. 相似文献
42.
43.
Hossam A. Zaki 《Computational Optimization and Applications》1995,4(1):23-45
State-of-the-art computational results have shown that the shortest augmenting path (SAP) methods are more efficient than other primal-dual and primal-simplex based methods for solving the linear assignment problem on uniprocessor computers. There is, however, some controversy concerning their merits when compared with Bertsekas' auction algorithm on multiprocessor computers. In this study we investigate the performance of these competing methods on the Alliant FX/8. For each method, theoretical motivation, sources of parallelism and computational results are presented. 相似文献
44.
The method of demodulation with two parallel matched fiber Bragg gratings( FBGs)system is introduced to enlarge the range of strain that can be detected by the FBG sensor system. 相似文献
45.
46.
Wengu Chen Yixin Lai 《分析论及其应用》2006,22(2):195-200
Let μ be a Borel measure on Rd which may be non doubling. The only condition that μ must satisfy is μ(Q) ≤ col(Q)n for any cube Q () Rd with sides parallel to the coordinate axes and for some fixed n with 0 < n ≤ d. The purpose of this paper is to obtain a boundedness property of fractional integrals in Hardy spaces H1 (μ). 相似文献
47.
In hardware design, it is necessary to simulate the anticipated behavior of the integrated circuit before it is actually cast in silicon. As simulation procedures are long due to the great number of tests to be performed, optimization of the simulation code is of prime importance. This paper describes two mathematical models for the minimization of the memory access times for a cycle-based simulator.An integrated circuit being viewed as a directed acyclic graph, the problem consists in building a graph order on the vertices, compatible with the relation order induced by the graph, in order to minimize a cost function that represents the memory access time. For both proposed cost functions, we show that the corresponding problems are NP-complete. However, we show that the special cases where the graphs are in-trees or out-trees can be solved in polynomial time. 相似文献
48.
In this short communication, we have evaluated the effect of thermal velocity of the plasma particles on the energy of resonantly
interacting energetic electrons with the propagating whistler mode waves as a function of wave frequency and L-value for the
normal and disturbed magnetospheric conditions. During the disturbed conditions when the magnetosphere is depleted in electron
density, the resonance energy of the electron enhances by an order of magnitude at higher latitudes, whereas the effect is
small at low latitudes. An attempt is made to explain the enhanced wave activity observed during magnetic storm periods. 相似文献
49.
切变模量和转动惯量实验的改进 总被引:2,自引:1,他引:1
设计了一种基于垂直轴定理的新型吊钩,对切变模量和转动惯量实验进行了改进,使之成为既可测定金属丝切变模量和环、柱等刚体的转动惯量,又可验证反映转动惯量重要性质的平行轴定理及垂直轴定理的多功能实验仪. 相似文献
50.