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991.
曲边多角形域上第一类边界积分方程的机械求积算法与分裂外推 总被引:4,自引:0,他引:4
This paper presents mechanical quadrature methods for solving first-kind boundary integral equations on polygonal regions, which possesses high accuracy O(h0^3)and low computing complexities. Moreover, the multivariate asymptotic expansion of the error with hi^3(i = 1,…,d) power is shown. Using the multi-parameter asymptotic expansion, we not only get a high precisioin approximation solution by means of the splitting extrapolation, but also derive a posteriori estimation. 相似文献
992.
993.
本文介绍了应用ICP-动态背景校正法测定催化剂中钯和铂的方法。并分析了几个主要元素的光谱干扰情况。 相似文献
994.
Summary We discuss a SN model with s-matter in the core, compatible with the set of experimental results obtained on SN 1987A by ν-detectors
and gravitational antennas. 相似文献
995.
In Ref. 1, Nocedal and Overton proposed a two-sided projected Hessian updating technique for equality constrained optimization problems. Although local two-step Q-superlinear rate was proved, its global convergence is not assured. In this paper, we suggest a trust-region-type, two-sided, projected quasi-Newton method, which preserves the local two-step superlinear convergence of the original algorithm and also ensures global convergence. The subproblem that we propose is as simple as the one often used when solving unconstrained optimization problems by trust-region strategies and therefore is easy to implement.This research was supported in part by the National Natural Science Foundation of China. 相似文献
996.
Qualitative (game of kind) outcomes of two-target games are analyzed in this paper, under both the zero-sum and nonzero-sum preference ordering of outcomes by the players. The outcome regions of each player are defined from a security standpoint. The secured draw and mutual-kill regions of a player depend explicitly on his preference ordering of outcomes and should be constructed separately for each player, especially in a nonzero-sum game. General guidelines are presented for identifying the secured outcome regions of players in a class of two-target games that satisfy an Isaacs-like condition, in terms of the qualitative solutions of the two underlying single-target pursuit-evasion games. A construction has been proposed for obtaining the qualitative solution of a large class of two-target games. Illustrative examples are included.This work was done while the first author was a Research Associate in the Department of Electrical Engineering at the Indian Institute of Science, Bangalore, and was financially supported by the Council of Scientific and Industrial Research, Delhi, India. 相似文献
997.
We show that for every potential space , there exists an approach region for which the associated maximal function is of weak-type, but the boundedness for the completed region is false, which is in contrast with the nontangential case.
998.
999.
There are many variants of successive quadratic programming (SQP) algorithms. Important issues include: the choice of either line search or trust region strategies; the QP formulation to be used; and how the QP is to be solved. Here, we consider the QP's proposed by Fletcher and Powell and discuss a specialized reduced-gradient procedure for solving them. A computer implementation is described, and the various options are compared on some well-known test problems. Factors influencing robustness and speed are identified. 相似文献
1000.
本文报道开发了一套用于微机的PIXE分析软件包和数据库。作为分析数据处理的第一步,文中主要介绍了解析PIXE谱和定性分析元素的计算机程序,该程序包括PIXE谱中本底的非线性近似,自动寻峰,谱拟合以及元素的双库检索等,并讨论了与程序运行有关的问题。本程序经国际实验室之间的比较,证明准确可靠。 相似文献