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排序方式: 共有275条查询结果,搜索用时 125 毫秒
71.
该文给出了一个求解非线性系统的信赖域方法.主要思想是通过引入松弛变量,将问题等价地转化为带非负约束的最优化问题.作者利用有效集策略,在每次迭代中只需求解一个低维的信赖域子问题,该信赖域子问题是通过截断共轭梯度法来近似求解的.在较弱的条件下,获得了一个更一般的收敛性结果. 相似文献
72.
Changyu Ren 《Journal of Mathematical Analysis and Applications》2008,339(2):1362-1373
For a class of elliptic Hessian operators raised by Caffarelli-Nirenberg-Spruck, the corresponding parabolic Monge-Ampère equation was studied, the existence and uniqueness of the admissible solution to the first initial-boundary value problem for the equation were established, which extended a result of Ivochkina-Ladyzhenskaya. 相似文献
73.
Lu Changyu 《东北数学》1994,(3)
ANecessaryandSufficientConditionforAdmissibilityofNonnegativeQuadraticEstimatorLuChangyu(鹿长余)(DepartmentofMathematics,Northea... 相似文献
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LI Qihu LI Shuqiu SUN Changyu YU Huabing 《声学学报:英文版》2007,26(3):193-197
The interference characteristics of towed platform noise resulted from propeller and towed body for active/passive towed array is analyzed. It is shown that, in shallow water environment, the direct wave and bottom/sea surface reflected wave will seriously affect the performance of sonar system. The formula for calculating the direction of arrival (DOA) of interference in terms of various parameters, such as array depth, length of tow cable, is derived. The effect of interference noise for the detection performance of sonar system is described. The results of system simulation provide the method for reducing the effect of these kind of interferences. 相似文献
78.
WANG Changyu YANG Xiaoqi & YANG Xinmin Institute oi Operations Research Qufu Normal University Qufu China Department of Applied Mathematics Dalian University of Technology Dalian China Department of Applied Mathematics The Hong Kong Polytechnic University Hong Kong China Department of Mathematics Chongqing Normal University Chongqing China 《中国科学A辑(英文版)》2005,48(2):261-276
In this paper, we study optimal value functions of generalized semi-infinite min-max programming problems on a noncompact set. Directional derivatives and subd-ifferential characterizations of optimal value functions are given. Using these properties, we establish first order optimality conditions for unconstrained generalized semi-infinite programming problems. 相似文献
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Ke Wang Changyu Tang Ping Zhao Hong Yang Qin Zhang Rongni Du Qiang Fu 《Macromolecular rapid communications》2007,28(11):1257-1264
A novel experimental technique to follow the crystallization processes of poly(propylene)/MWCNT composites that experience a steady shear deformation using dynamic melt rheometry is described. The effects of heterogeneous nucleation, temperature, and preshear on the crystallization behaviors were determined. A quantitative evaluation of crystallization kinetics difference between quiescent and preshear conditions could be achieved. By combining rheology with POM, we demonstrate that two different crystallization processes account for the shear‐enhanced crystallization at low and high temperatures, respectively.