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61.
In this paper, we propose and analyze an SQP-type method for solving linearly constrained convex minimization problems where the objective functions are too complex to be evaluated exactly. Some basic results for global convergence and local superlinear convergence are obtained according to the properties of the approximation sequence. We illustrate the applicability of our approach by proposing a new method for solving two-stage stochastic programs with fixed recourse. 相似文献
62.
CdZnTe核探测器的蒙特卡罗模拟的初步研究 总被引:6,自引:0,他引:6
以CdZnTe核探测器的工作原理为依据,探测器内反应的随机性和反应产生的电子空穴对数目的统计规律为物理模型,应用Visual C + + 自行编制了蒙特卡罗模拟软件.模拟了γ射线在CdZnTe探测器中的响应能谱,并将模拟结果与实际器件的测试结果进行了比较讨论.模拟能谱与实际测得的能谱的主峰符合较好.此外,通过分析57Co源辐照下探测效率与器件厚度的关系,可以推测探测效率达到最大时所对应CdZnTe探测器的理想厚度 相似文献
63.
For any Sturm-Liouville problem with a separable boundary condition and whose leading coefficient function changes sign (exactly once), we first give a geometric characterization of its eigenvalues λn using the eigenvalues of some corresponding problems with a definite leading coefficient function. Consequences of this characterization include simple proofs of the existence of the λn's, their Prüfer angle characterization, and a way for determining their indices from the zeros of their eigenfunctions. Then, interlacing relations among the λn's and the eigenvalues of the corresponding problems are obtained. Using these relations, a simple proof of asymptotic formulas for the λn's is given. 相似文献
64.
Guo Qing LI Zhong Jiao JIA 《中国化学快报》2003,14(1):62-65
Two new ionone derivatives,named rhododendrone and rhododendronside,were isolated from the alcohoilc extract of the aerial parts of Rhododendron przwalskii Maxim.Their structures were elucidated on the basis of spectroscopic analysis. 相似文献
65.
In this paper, a successive supersymmetric rank‐1 decomposition of a real higher‐order supersymmetric tensor is considered. To obtain such a decomposition, we design a greedy method based on iteratively computing the best supersymmetric rank‐1 approximation of the residual tensors. We further show that a supersymmetric canonical decomposition could be obtained when the method is applied to an orthogonally diagonalizable supersymmetric tensor, and in particular, when the order is 2, this method generates the eigenvalue decomposition for symmetric matrices. Details of the algorithm designed and the numerical results are reported in this paper. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
66.
A uniqueness theorem for two distinct non-constant meromorphic functions that share three values of finite weights is proved, which generalizes two previous results by H.X. Yi, and X.M. Li and H.X. Yi. As applications of it, many known results by H.X. Yi and P. Li, etc. could be improved. Furthermore, with the concept of finite-weight sharing, extensions on Osgood-Yang's conjecture and Mues' conjecture, and a generalization of some prevenient results by M. Ozawa and H. Ueda, ect. could be obtained. 相似文献
67.
68.
Wei Gang SU Huai Jie ZHONG 《数学学报(英文版)》2006,22(2):515-522
This paper introduces the concept of the generalized Riesz operators and the concept of the generalized West decomposition of a general operator which generalizes the definition of the West decomposition of Riesz operators, and proves that the following three statements are equivalent on a general Banach space:
(a) Every generalized Riesz operator has the generalized West decomposition;
(b) Every operator makes strong Stampfli theorem true; Every operator has Apostol's compact correction. 相似文献
69.
70.