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221.
In this paper we propose a smoothing Newton-type algorithm for the problem of minimizing a convex quadratic function subject to finitely many convex quadratic inequality constraints. The algorithm is shown to converge globally and possess stronger local superlinear convergence. Preliminary numerical results are also reported. Mathematics Subject Classification (1991): 90C33, 65K10 This author’s work was also partially supported by the Scientific Research Foundation of Tianjin University for the Returned Overseas Chinese Scholars and the Scientific Research Foundation of Liu Hui Center for Applied Mathematics, Nankai University-Tianjin University.  相似文献   
222.
By smoothing a perturbed minimum function, we propose in this paper a new smoothing function. The existence and continuity of a smooth path for solving the nonlinear complementarity problem (NCP) with a P 0 function are discussed. We investigate the boundedness of the iteration sequence generated by noninterior continuation/smoothing methods under the assumption that the solution set of the NCP is nonempty and bounded. Based on the new smoothing function, we present a predictor-corrector smoothing Newton algorithm for solving the NCP with a P 0 function, which is shown to be globally linearly and locally superlinearly convergent under suitable assumptions. Some preliminary computational results are reported.  相似文献   
223.
马昌凤  梁国平 《数学杂志》2004,24(4):399-402
提出了求解混合互补问题的一个光滑逼近算法,并在一定条件下证明了该算法的全局收敛性.  相似文献   
224.
江秀娟  周申蕾  林尊琪  朱俭 《物理学报》2006,55(9):4595-4601
用数值方法研究了激光驱动器系统中使用光谱色散平滑单元后光束的衍射特性.模拟结果表明,光谱色散会使光束衍射光斑变大,近场空间强度均匀性改善,而远场光斑内部存在光强接近于均匀分布的区域.进一步分析了光谱色散平滑单元中相位调制器的调制深度、调制频率及光栅色散系数等主要元件参数对光束传输特性的影响,发现在一定情况下光斑内部会出现较强的强度调制. 关键词: 光谱色散平滑 光束衍射 近场 远场  相似文献   
225.
光学零件高效加工生产线建成后,工艺人员应解决的关键问题就是生产线内部各道工序之间的匹配。本文较系统地讨论了从铣磨、精磨到抛光各道工序之间在光圈、光学粗糙度、加工余量诸方面的匹配关系。这三个方面既互相独立、又互相影响。每道工序都要同时满足这三方面的要求,才能保证高效线的稳定、高产  相似文献   
226.
Underwriting the risk of rare disorders in long-term insurance often relies on rates of onset estimated from quite small epidemiological studies. These estimates can have considerable sampling uncertainty and any function based upon them, such as a premium rate, is also an estimate subject to uncertainty. This is particularly relevant in the case of genetic disorders, because the acceptable use of genetic information may depend on establishing its reliability as a measure of risk. The sampling distribution of a premium rate is hard to estimate without access to the original data, which is rarely possible. From two studies of adult polycystic kidney disease (APKD) we obtain, not the original data, but the cases and exposures used for Kaplan-Meier estimates of the survival probability. We use three resampling methods with these data, namely: (a) the standard bootstrap; (b) the weird bootstrap; and (c) simulation of censored random lifetimes. Rates of onset were obtained from each simulated sample using kernel-smoothed Nelson-Aalen estimates, hence critical illness insurance premium rates for a mutation carrier or a member of an affected family. From 10,000 such samples we estimate the sampling distributions of the premium rates, finding considerable uncertainty. Very careful consideration should be given before using small-sample epidemiological data to deal with insurance problems.  相似文献   
227.
泛代数的型扩张   总被引:1,自引:1,他引:0  
引入了泛代数型扩张的概念,对涉及型扩张的几个重要问题,尤其是两类特殊的型扩张作了讨论,就型扩张集、有关的基数函数及积代数的型扩张研究分别得到了重要结果。  相似文献   
228.
SuppressionofInterferenceSpecklesintheUniformLineFocusSystemofSegmentedWedgeArrayUsingPhase-disturbedPlate¥LIUZhongyong;ZHENG...  相似文献   
229.
This paper is concerned with the parametric investigation on the structural dynamic response of moving fuel‐storage tanks with baffles. Since the structural dynamic behaviour is strongly coupled with interior liquid motion, the design of a fuel‐storage tank securing the structural stability becomes the appropriate suppression of the flow motion, which is in turn related to the baffle design. In order to numerically investigate the parametric dynamic characteristics of moving tanks, we employ the arbitrary Lagrangian–Eulerian (ALE) finite element method that is widely being used to deal with the problems with free surface, moving boundary, large deformation and interface contact. Following the theoretical and numerical formulations of fluid‐structure interaction problems, we present parametric numerical results of a cylindrical fuel‐storage tank moving with uniform vertical acceleration, with respect to the baffle number and location, and the inner‐hole diameter. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
230.
一种解决不等式约束优化问题的光滑牛顿法   总被引:2,自引:0,他引:2  
本通过引入松弛变量和Fischer函数把带有不等式约束优化问题的K-T条件转化为一个等价的非线性系统,并引入一参数μ,从而提出了一种新的光滑牛顿法。在适当的条件下,证明了算法的全局收敛性,并提供了数值结果。  相似文献   
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