检索结果-南通市图书馆

Chih-chen Wang: the social responsibility of scientists

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

National Science Review 2021年第4期8卷 195-200页

作者： chao gu the Department of History of Science Technology and Medicine Peking University

Chih-chen Wang is a distinguished biochemist and molecular biologist, and an Academician of the Chinese Academy of Sciences (CAS).From 2008 to 2013, she was a vice chairperson of the National Committee of the Chinese People’s Political Consultative Conference(CPPCC). As a young researcher, Wang participated in research on insulin. Since the 1990s, she has been focusing on the study of protein folding, and has initiated a new research area of isomerase and molecular chaperones in China.

关键词：

A Dwindling Filter Line Search Algorithm for Nonlinear Equality Constrained Optimization

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2015年第3期28卷 623-637页

作者： gu chao ZHU Detong School of Mathematics and Informatics Shanghai Lixin University of Commerce Department of Mathematics Shanghai Normal University

This paper proposes a dwindling filter line search algorithm for nonlinear equality constrained optimization. A dwindling filter, which is a modification of the traditional filter, is employed in the algorithm. The envelope of the dwindling filter becomes thinner and thinner as the step size approaches zero. This new algorithm has more flexibility for the acceptance of the trial step and requires less computational costs compared with traditional filter algorithm. The global and local convergence of the proposed algorithm are given under some reasonable conditions. The numerical experiments are reported to show the effectiveness of the dwindling filter algorithm.

关键词： Convergence dwindling filter line search nonlinear optimization secant update.

A NONMONOTONE LINE SEARCH FILTER METHOD WITH REDUCED HESSIAN UPDATING FOR NONLINEAR OPTIMIZATION

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2013年第4期26卷 534-555页

作者： gu chao ZHU Detong School of Mathematics and Informatics Shanghai Lixin University of Commerce Business College Shanghai Normal University

This paper proposes a nonmonotone line search filter method with reduced Hessian updating for solving nonlinear equality constrained *** order to deal with large scale problems,a reduced Hessian matrix is approximated by BFGS *** new method assures global convergence without using a merit *** Lagrangian function in the filter and nonmonotone scheme,the authors prove that the method can overcome Maratos effect without using second order correction step so that the locally superlinear convergence is *** primary numerical experiments are reported to show effectiveness of the proposed algorithm.

关键词： Convergence filter method lagrangian function line search maratos effect nomnono- tone.

A Dwindling Filter Algorithm with a Modified Subproblem for Nonlinear Inequality Constrained Optimization

在线全文

学校读者我要写书评

暂无评论

Chinese Annals of Mathematics,Series B 2014年第2期35卷 209-224页

作者： chao gu Detong ZHU School of Mathematics and Information Shanghai Lixin University of Commerce Department of Mathematics Shanghai Normal University

The authors propose a dwindling filter algorithm with Zhou's modified subproblem for nonlinear inequality constrained *** feasibility restoration phase,which is always used in the traditional filter method,is not *** mild conditions,global convergence and local superlinear convergence rates are *** results demonstrate that the new algorithm is effective.

关键词： Modified subproblem Dwindling filter Feasibility restoration phase Convergence Constrained optimization

Interference aware routing for mobile ad hoc networks based on node's sending and receiving capabilities

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2013年第4期20卷 73-79,111页

作者： gu chao ZHU Qi Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and Telecommunications Key Lab on Wideband Wireless Communications and Sensor Network Technology of Ministry of Education Nanjing University of Posts and Telecommunications

How to efficiently build routes among nodes is increasing important for mobile ad hoc networks （MANETs）. This paper puts forward an interference aware routing protocol called Interference aware cross layer routing protocol （IA-CLR） for MANETs based on the IEEE 802.11 medium access layer （MAC）. By defining the node＇s sending and receiving capabilities, IA-CLR can indicate the interference strength of the link in a real and comprehensive way. Further more, in order to choose the route with minimum bottleneck link interference, a new routing metric is proposed by combining the MAC layer and the network layer for cross layer design. Simulation results show that IA-CLR can significantly improve the performances of network such as the average end-to-end delay, the packets loss ratio and the throughput.

关键词： ad hoc networks routing protocol routing design interference aware

Global and Local Convergence of a New Affine Scaling Trust Region Algorithm for Linearly Constrained Optimization

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2016年第10期32卷 1203-1213页

作者： chao gu De Tong ZHU School of Mathematics and Information Shanghai LiXin University of Commerce Department of Mathematics Shanghai Normal University

Chen and Zhang [Sci. China, Set. A, 45, 1390-1397 （2002）] introduced an affine scaling trust region algorithm for linearly constrained optimization and analyzed its global convergence. In this paper, we derive a new affine scaling trust region algorithm with dwindling filter for linearly constrained optimization. Different from Chen and Zhang＇s work, the trial points generated by the new algorithm axe accepted if they improve the objective function or improve the first order necessary optimality conditions. Under mild conditions, we discuss both the global and local convergence of the new algorithm. Preliminary numerical results are reported.

关键词： Linearly constrained optimization affine scaling trust region dwindling filter~ conver-gence

Investigation of the structural, electronic and mechanical properties of CaO–SiO_(2) compound particles in steel based on density functional theory

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 744-755页

作者： chao gu Ziyu Lyu Qin Hu Yanping Bao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China

CaO–SiO_(2)compounds compromise one of the most common series of oxide particles in liquid steels, which could significantly affect the service performance of the steels as crack initiation sites. However, the structural, electronic, and mechanical properties of the compounds in CaO–SiO_(2)system are still not fully clarified due to the difficulties in the experiments. In this study, a thorough investigation of these properties of CaO–SiO_(2)compound particles in steels was conducted based on first-principles density functional theory. Corresponding phases were determined by thermodynamic calculation, including gamma dicalcium silicate(γ-C2S), alpha-prime(L) dicalcium silicate(αL′-C2S), alpha-prime(H) dicalcium silicate(αH′-C2S), alpha dicalcium silicate(α-C2S), rankinite(C3S2), hatrurite(C3S), wollastonite(CS), and pseudowollastonite(Ps-CS). The results showed that the calculated crystal structures of the eight phases agree well with the experimental results. All the eight phases are stable according to the calculated formation energies, and γ-C2S is the most stable. O atom contributes the most to the reactivity of these phases. The Young’s modulus of the eight phases is in the range of 100.63–132.04 GPa. Poisson’s ratio is in the range of0.249–0.281. This study provided further understanding concerning the CaO–SiO_(2)compound particles in steels and fulfilled the corresponding property database, paving the way for inclusion engineering and design in terms of fracture-resistant steels.

关键词： CaO–SiO_(2) density functional theory structural property electronic property mechanical property

The third type DC flow in pulse tube cryocooler

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2009年第12期52卷 3491-3496页

作者： ZHOU Yuan gu chao CAI HuiKun Key Laboratory of Cryogenics Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Graduate University of Chinese Academy of Sciences Beijing 100049China

New phenomena discovered in the experimental research of the ultra-high frequency pulse tube cryocooler were *** cause of the new phenomena was analyzed and the third type DC flow was discovered in the pulse tube *** third type DC flow not only deteriorated cooling capacity but also led to temperature instability of the pulse tube *** the fluid network theory and the simple regenerator model,the root of the third type DC flow was concisely investigated in theory. The asymmetric resistance of oscillating flow in pulse tube cryocooler was the key mechanism of the third type DC *** suppression methods were briefly discussed.

关键词： pulse tube cryocooler DC flow fluid network theory flow resistance

A FILTER SECANT METHOD WITH NONMONOTONE LINE SEARCH FOR EQUALITY CONSTRAINED OPTIMIZATION

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science & Complexity 2010年第4期23卷 846-860页

作者： chao gu Detong ZHU School of Mathematics and Informatics Shanghai LiXin University of Commerce Shanghai 201620 China Business College Shanghai Normal University Shanghai 200234 China

This paper proposes a filter secant method with nonmonotone line search for non-linearequality constrained *** Hessian of the Lagrangian is approximated using the BFGSsecant *** new method has more flexibility for the acceptance of the trial step and requires lesscomputational costs compared with the monotone *** global and local convergence of the proposedmethod are given under some reasonable ***,two-step Q-superlinear convergence rateis established by introducing second order correction *** numerical experiments are reported toshow the effectiveness of the proposed algorithm.

关键词： Convergence filter method line search nonmonotone secant update