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Optimal value functions of generalized semi-infinite min-max programming on a noncompact set

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Science China mathematics 2005年第2期48卷 261-276页

作者： WANG Changyu, YANG Xiaoqi & YANG Xinmin Institute oi Operations Research, Qufu Normal university, Qufu 2.3165, China department of applied mathematics,{2., dalian 11602., China department of applied mathematics, The Hong Kong Polytechnic university, Hong Kong, China department of mathematics, Chongqing Normal university, Chongqing 400047, China Institute of 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

In this paper, we study optimal value functions of generalized semi-infinite min-max programming problems on a noncompact set. Directional derivatives and subdifferential characterizations of optimal value functions are given. Using these properties,we establish first order optimality conditions for unconstrained generalized semi-infinite programming problems.

关键词： optimal value function, directional derivative, subdifferential, semi-infinite programming, first order optimality condition.

Analysis on cohesive crack opening displacement considering the strain softening effect

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1, XU Shilang2.& ZHAO Xiqiang3 1. Mechanics department, Shandong university of {2., Zibo 2.5049, China 2. Civil Engineering department, dalian university of technology, dalian 11602., China 3. mathematics department, Ocean university of China, Qingdao 2.6071, China Mechanics department Shandong University of Technology Zibo China Civil Engineering department Dalian University of Technology Dalian China mathematics department Ocean University of China Qingdao China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

A FEW RESULTS ON ARNOLDI'S METHOD AND IOM FOR LARGE NON-HERMITIAN LINEAR SYSTEMS

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Systems Science and Mathematical Sciences 2000年第3期13卷 231-235页

作者： JIA Zhongxiao(department of applied mathematics, dalian university of technology,{2., China) 大连理工大学应用数学系辽宁大连 116024

Arnoldi’s method and the incomplete orthogonalization method (IOM) for large non-Hermitian linear systerns are studied. It is shown that the inverse of a general nonsingular j × j Hessenberg matrir can be updated in O(j2. flops from that of its (j -1) × (j - 1) principal submatrir. The updating recursion of inverses of the Hessenberg matrices does not need any QR or LU decompostion as commonly used in the literature. Some updating recursions of the residual norms and the approximate solutions obtained by these two methods are derived. These results are appealing because they allow one to decide when the methods converge and show one how to compute approximate solutions very cheaply and easily.

关键词： Large non-Hermitian linear system Arnoldi’s method IOM residual approximate solution recursion

Phase Separation and Theta-compositions of PPES/NMP/non-solvent Systems

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Journal of Materials Science & technology 2005年第3期21卷 430-432页

作者： Yi SU and Xigao JIAN department of Polymer Science, dalian university of technology, {2. 116012. China department of Polymer Science Dalian University of Technology Dalian 116012 China

Poly (phthalazinone ether sulfone) (PPES) with 1:1 and 1:3 ratios of bisphenol A (BPA) unit to phthalazinone unit were selected as samples. Polymer precipitation curves for the ternary systems PPES (1:1)/NMP/ non-solvent and PPES (1:3)/NMP/non-solvent were determined by a titration method. Comparison between two sets of data is made. Non-solvents used were H2., ethyl ether (EE), diethylene glycol (DEGC), ethyleneglycol methylether (EGME) and butanone (BO). NMP/non-solvent theta-compositions for PPES (1:1) and PPES (1:3) were also estimated. It was found that the volume ratio of non-solvent to NMP at the property mutation or worsening of PPES membrane is close to the theta-composition.

关键词： Polymer precipitation curve Poly (phthalazinone ether sulfone) Theta-composition

Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer’s disease

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Neural Regeneration Research 2024年第11期19卷 2467-2479页

作者： Yong Tang Jing Wei Xiao-Fang Wang Tao Long Xiaohong Xiang Liqun Qu Xingxia Wang Chonglin Yu Xingli Xiao Xueyuan Hu Jing Zeng Qin Xu Anguo Wu Jianming Wu dalian Qin Xiaogang Zhou Betty Yuen-Kwan Law Dr.Neher’s Biophysics Laboratory for Innovative Drug Discovery State Key Laboratory of Quality Research in Chinese MedicineMacao University of Science and TechnologyMacao Special Administrative RegionChina Sichuan Key Medical Laboratory of New Drug Discovery and Druggability Evaluation Luzhou Key Laboratory of Activity Screening and Druggability Evaluation for Chinese Materia Medica Southwest Medical UniversityLuzhouSichuan ProvinceChina Eye School and Key Laboratory of Sichuan Province Ophthalmopathy Prevention&Cure and Visual Function Protection of Chengdu university of TCM ChengduSichuan ProvinceChina School of Basic Medical Sciences Southwest Medical UniversityLuzhouSichuan ProvinceChina department of Ophthalmology The Affiliated Hospital of Southwest Medical UniversityLuzhouSichuan ProvinceChina department of Neurology The First People’s Hospital of NeijiangNeijiangSichuan ProvinceChina

Amyloid-beta-induced neuronal cell death contributes to cognitive decline in Alzheimer’s *** Reticulatae Semen has diverse beneficial effects on neurodegenerative diseases,including Parkinson’s and Huntington’s diseases,however,the effect of Citri Reticulatae Semen on Alzheimer’s disease remains *** the current study,the anti-apoptotic and autophagic roles of Citri Reticulatae Semen extract on amyloid-beta-induced apoptosis in PC12.cells were first *** Reticulatae Semen extract protected PC12.cells from amyloid-beta-induced apoptosis by attenuating the Bax/Bcl-2.ratio via activation of *** addition,Citri Reticulatae Semen extract was confirmed to bind amyloid-beta as revealed by biolayer interferometry in vitro,and suppress amyloid-beta-induced pathology such as paralysis,in a transgenic Caenorhabditis elegans in vivo ***,genetically defective Caenorhabditis elegans further confirmed that the neuroprotective effect of Citri Reticulatae Semen extract was *** importantly,Citri Reticulatae Semen extract was confirmed to improve cognitive impairment,neuronal injury and amyloid-beta burden in 3×Tg Alzheimer’s disease *** revealed by both in vitro and in vivo models,these results suggest that Citri Reticulatae Semen extract is a potential natural therapeutic agent for Alzheimer’s disease via its neuroprotective autophagic effects.

关键词： Alzheimer’s disease amyloid-beta apoptosis autophagy Caenorhabditis elegans Citri Reticulatae Semen

LEVEL SET METHOD FOR TOPOLOGICAL OPTIMIZATION APPLYING TO STRUCTURE, MECHANISM AND MATERIAL DESIGNS

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 200-209页

作者： Mei Yulin Wang Xiaoming department of Mechanical Engineering,dalian {2. of technology,dalian 11602.,China department of Mechanical Engineering Dalian University of Technology Dalian 116024

Based on a level set model, a topology optimization method has been suggestedrecently. It uses a level set to express the moving structural boundary, which can flexibly handlecomplex topological changes. By combining vector level set models with gradient projectiontechnology, the level set method for topological optimization is extended to a topologicaloptimization problem with multi-constraints, multi-materials and multi-load cases. Meanwhile, anappropriate nonlinear speed, mapping is established in the tangential space of the activeconstraints for a fast convergence. Then the method is applied to structure designs, mechanism andmaterial designs by a number of benchmark examples. Finally, in order to further improvecomputational efficiency and overcome the difficulty that the level set method cannot generate newmaterial interfaces during the optimization process, the topological derivative analysis isincorporated into the level set method for topological optimization, and a topological derivativeand level set algorithm for topological optimization is proposed.

关键词： Level set method Topology optimization Mean curvature flow Materialdesign Mechanism design Topological derivative

Rational Form Solitary Wave Solutions and Doubly Periodic Wave Solutions to (1+1)-Dimensional Dispersive Long Wave Equation

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Communications in Theoretical Physics 2005年第6期43卷 975-982页

作者： WANG Qi CHEN Yong ZHANG Hong-Qing department of applied mathematics, dalian university of technology,{2.. China department of mathematics, Ningbo university, Ningbo 3152.1, China department of Physics, Shanghai Jiao Tong university, Shanghai 2.0030, China department of applied mathematics Dalian University of Technology Dalian 116024 China department of mathematics Ningbo University Ningbo 315211 China department of Physics Shanghai Jiao Tong University Shanghai 200030 China

In this work we devise an algebraic method to uniformly construct rational form solitary wave solutionsand Jacobi and Weierstrass doubly periodic wave solutions of physical interest for nonlinear evolution equations. Withthe aid of symbolic computation, we apply the proposed method to solving the (1+1)-dimensional dispersive long wavethe (1+1)-dmensional dispesive long wavedelliptic donbly periodc wave solutions as special cases.

关键词： elliptic equation rational expansion method rational form solitary wave solutions rational form Jacobi and Weierstrass doubly periodic wave solutions symbolic computation (1+1)-dimensional dispersive long wave equation

Analytical theory of flexural behavior of concrete beam reinforced with textile-combined steel

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Science China(Technological Sciences) 2010年第6期53卷 1700-1710页

作者： XU ShiLang & YIN ShiPing department of Civil Engineering,dalian {2. of technology,dalian 11602.,China department of Civil Engineering Dalian University of Technology Dalian China

Textile-reinforced concrete (TRC) is a new high performance cementitious composite material,which not only has superior corrosion resistance but also can effectively limit the development of concrete cracks and make the crack width and spacing of concrete become ***,due to the brittle feature of fiber materials,the TRC structural member has no distinct failure symptom when it arrives at its ultimate *** the same time,ordinary reinforced concrete (RC) elements have large dead weight and can not efficiently restrict the expansion of the main crack of structures because of the restriction of their special cover *** order to overcome the disadvantages of both the TRC and the RC,a new architecture reinforced with textile-combined steel is proposed in this study,making full use of the advantages of the above two *** cover concrete at the tension zone of an RC element is partially replaced with TRC and thus the steel reinforcements replaced with textiles are *** with the old one,the new structure has less dead weight and has the merits of service safety and good *** flexural development process of the proper beam with this new structure is investigated in this paper and based on the plane section assumption,analytical equations are derived by using nonlinear analysis theory,including the load-carrying capacity at different stages and moment-curvature relationship and mid-span deflection during the entire loading *** between the calculated and the experimental results reveals satisfactory agreement and thus verifies the feasibility of the equations.

关键词： textile-reinforced concrete limiting the crack beam reinforced with textile-combined steel flexural behavior analytical theory

Biological exposure models for oil spill impact analysis

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Journal of Environmental Sciences 2000年第4期12卷 482-485页

作者： XIONG De qi 1, Mark Reed 2. Narve Ekrol 2.(1. department of Marine Environmental Engineering, dalian Maritime {2., dalian 11602., China E mail: deqi@*** 2. department of Environmental Engineering, SINTEF applied Chemistry Institut 大连海事大学辽宁大连 1 1 6 0 2 SINTEF applied Chemistry Institute 挪威 Trondheim 70 3 4

The oil spill impact analysis (OSIA) software system has been developed to supply a tool for comprehensive, quantitative environmental impact assessments resulting from oil spills. In the system, a biological component evaluates potential effects on exposed organisms based on results from a physico chemical fates component, including the extent and characteristics of the surface slick, and dissolved and total concentrations of hydrocarbons in the water column. The component includes a particle based exposure model for migratory adult fish populations, a particle based exposure model for spawning planktonic organisms (eggs and larvae), and an exposure model for wildlife species (sea birds or marine mammals). The exposure model for migratory adult fish populations simulates the migration behaviors of fish populations migrating to or staying in their feeding areas, over wintering areas or spawning areas, and determines the acute effects (mortality) and chronic accumulation (body burdens) from the dissolved contaminant. The exposure model for spawning planktonic organisms simulates the release of eggs and larvae, also as particles, from specific spawning areas during the spawning period, and determines their potential exposure to contaminants in the water or sediment. The exposure model for wild species calculates the exposure to surface oil of wildlife (bird and marine mammal) categories inhabiting the contaminated area. Compared with the earlier models in which all kinds of organisms are assumed evenly and randomly distributed, the updated biological exposure models can more realistically estimate potential effects on marine ecological system from oil spill pollution events.

关键词： oil spill biological exposure acute effects chronic accumulation migration of fish spawning of eggs and larvae habitat