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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:3
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作者 丁协平 《应用数学和力学》 EI CSCD 北大核心 2004年第6期563-571,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 集值映象组 非空交定理 广义矢量平衡问题组 乘积G凸空间
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A CLASS OF NONLOCAL BOUNDARY VALUE PROBLEMS OF NONLINEAR ELLIPTIC SYSTEMS IN UNBOUNDED DOMAINS 被引量:64
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作者 莫嘉琪 欧阳成 《Acta Mathematica Scientia》 SCIE CSCD 2001年第1期93-97,共5页
The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems ar... The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems are studied. 展开更多
关键词 elliptic system boundary value problem comparison theorem
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Analysis of problems in urban green space system planning in China 被引量:16
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作者 WANG Xiao-Jun 《Journal of Forestry Research》 SCIE EI CAS CSCD 2009年第1期79-82,共4页
This paper discusses the major problems in urban green space system (UGSS) planning at both general and special planning levels in China. At general planning level, the problems of the UGSS are mainly from the ignor... This paper discusses the major problems in urban green space system (UGSS) planning at both general and special planning levels in China. At general planning level, the problems of the UGSS are mainly from the ignorance in the characteristics of urban nature spaces and the limitation factors of the urban planning system. Great importance is attached to the green spaces in the built area of city, but the green spaces in surrounding areas of the city is unnoticed. Furthermore, because the area of UGSS planning is strictly limited by the administrative zoning, the green space system loses its integrity and rationality in spatial patterns. The schedules of urban development planning mismatched the paces and progresses of the ecological restoration cycles. At special plan level, the problem of the UGSS in China is that the green spaces quantity was over emphasized but the rationality of their layouts is neglected.. Meanwhile, the requirement of the spatial structures and the green spaces layouts to balance between the urban development and the natural ecological environments is often ignored. With regard to the layouts in the UGSS planning practices, the existing problems are the compromising to the existing land-uses, the 'filling in' approach to plan green spaces and an over-emphasis on the layout patterns. 展开更多
关键词 Urban Green Space system (UGSS) PLANNING problemS quantity layout
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GLOBALLY SMOOTH SOLUTIONS TO CAUCHY PROBLEM OF A QUASILINEAR HYPERBOLIC SYSTEM ARISING IN BIOLOGY 被引量:2
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作者 郑永树 《Acta Mathematica Scientia》 SCIE CSCD 2001年第4期460-468,共9页
This article considers Cauchy problem u(t) - (uv)(x) = 0, v(t) - u(x) = 0, u(x, 0) = u(0) (x) > 0, v(x, 0) = v(0)(x). A necessary and sufficient condition in guaranteeing that Cauchy problem admits a global C-1-sol... This article considers Cauchy problem u(t) - (uv)(x) = 0, v(t) - u(x) = 0, u(x, 0) = u(0) (x) > 0, v(x, 0) = v(0)(x). A necessary and sufficient condition in guaranteeing that Cauchy problem admits a global C-1-solution on t greater than or equal to 0 is obtained. 展开更多
关键词 nonlinear hyperbolic system Cauchy problem global C-1-solution
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Problems of Rural Food Safety and Strategies of Constructing Supervision System 被引量:7
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作者 XIAO Yue-qiang 《Asian Agricultural Research》 2011年第7期54-57,79,共5页
This paper expounds the practical necessity of constructing diversified rural food safety supervision system as follows: it is the necessary requirements of guaranteeing people's health and life safety; it is an i... This paper expounds the practical necessity of constructing diversified rural food safety supervision system as follows: it is the necessary requirements of guaranteeing people's health and life safety; it is an important component of governmental function of social management and the logical extension of administrative responsibilities; it is the basis of maintaining order of rural society and constructing harmonious society. The main problems existing in the supervision of rural food safety are analyzed as follows: first, the legislative work of rural food safety lags behind to some extent; second, the supervision of governmental departments on rural food safety is insufficient; third, the industrial supervision mechanism of rural food security is not perfect; fourth, the role of rural social organizations in supervising food safety is limited; fifth, the farmers' awareness of food safety supervision is not strong. Based on these problems, the targeted strategies of constructing diversified rural food safety supervision system are put forward as follows: accelerate the legislation of rural food safety, and ensure that there are laws to go by; give play to the dominant role of government, and strengthen administrative supervision on rural food safety; perfect industrial convention of rural food safety, and improve industrial supervision mechanism; actively support the fostering of social organizations, and give play to the role of supervision of organizations; cultivate correct concept of rights and obligations of farmers, and form awareness of food safety supervision. 展开更多
关键词 Rural food safety SUPERVISION Main problems system construction China
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Eigenvalue Problem of Doubly Stochastic Hamiltonian Systems with Boundary Conditions 被引量:1
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作者 HAN YUE-CAI MA YONG 《Communications in Mathematical Research》 CSCD 2009年第1期30-36,共7页
In this paper, we investigate the eigenvalue problem of forward-backward doubly stochastic dii^erential equations with boundary value conditions. We show that this problem can be represented as an eigenvalue problem o... In this paper, we investigate the eigenvalue problem of forward-backward doubly stochastic dii^erential equations with boundary value conditions. We show that this problem can be represented as an eigenvalue problem of a bounded continuous compact operator. Hence using the famous Hilbert-Schmidt spectrum theory, we can characterize the eigenvalues exactly. 展开更多
关键词 doubly stochastic Hamiltonian system eigenvalue problem spectrum theory
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A Comparative Study of Genetic Algorithm Parameters for the Inverse Problem-based Fault Diagnosis of Liquid Rocket Propulsion Systems 被引量:1
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作者 Erfu Yang Hongjun Xiang +1 位作者 Dongbing Gu Zhenpeng Zhang 《International Journal of Automation and computing》 EI 2007年第3期255-261,共7页
Fault diagnosis of liquid rocket propulsion systems (LRPSs) is a very important issue in space launch activities particularly when manned space missions are accompanied, since the safety and reliability can be signi... Fault diagnosis of liquid rocket propulsion systems (LRPSs) is a very important issue in space launch activities particularly when manned space missions are accompanied, since the safety and reliability can be significantly enhanced by exploiting an efficient fault diagnosis system. Currently, inverse problem-based diagnosis has attracted a great deal of research attention in fault diagnosis domain. This methodology provides a new strategy to model-based fault diagnosis for monitoring the health of propulsion systems. To solve the inverse problems arising from the fault diagnosis of LRPSs, GAs have been adopted in recent years as the first and effective choice of available numerical optimization tools. However, the GA has many control parameters to be chosen in advance and there still lack sound theoretical tools to analyze the effects of these parameters on diagnostic performance analytically. In this paper a comparative study of the influence of GA parameters on diagnostic results is conducted by performing a series of numerical experiments. The objective of this study is to investigate the contribution of individual algorithm parameter to final diagnostic result and provide reasonable estimates for choosing GA parameters in the inverse problem-based fault diagnosis of LRPSs. Some constructive remarks are made in conclusion and will be helpful for the implementation of GA to the fault diagnosis practice of LRPSs in the future. 展开更多
关键词 Liquid rocket propulsion systems inverse problem fault diagnosis genetic algorithm comparative study.
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Achievements and Problems of Reform of Investment Management System for Shanghai Pilot Free Trade Zone 被引量:1
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作者 Chengrong PAN 《Asian Agricultural Research》 2014年第11期30-33,共4页
The establishment of Shanghai Pilot Free Trade Zone provides many possibilities for China's economic construction. This paper made a comparative analysis on investment management system of Shanghai Pilot Free Trad... The establishment of Shanghai Pilot Free Trade Zone provides many possibilities for China's economic construction. This paper made a comparative analysis on investment management system of Shanghai Pilot Free Trade Zone and traditional investment management system,discussed achievements and problems of reform of investment management system of Shanghai Pilot Free Trade Zone,and finally came up with pertinent policy recommendations. 展开更多
关键词 SHANGHAI PILOT Free TRADE Zone INVESTMENT manageme
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The Analysis of the Problems and Solutions about the Application of ERP System in Apparel Enterprise
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作者 闫琳 陈素英 《科技信息》 2012年第11期64-65,共2页
This paper surveys the situation of the application of apparel enterprise ERP system and analyzes the problems appeared in the process of ERP system implementation.Then it puts forward the corresponding solutions to i... This paper surveys the situation of the application of apparel enterprise ERP system and analyzes the problems appeared in the process of ERP system implementation.Then it puts forward the corresponding solutions to improve the success rate of using ERP. 展开更多
关键词 服装行业 服装设计 纺织服装 ERP
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Boundary value problems for two types of degenerate elliptic systems in R^4 被引量:3
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作者 WANG Li-ping WEN Guo-chun 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2016年第4期469-480,共12页
Firstly, the Riemann boundary value problem for a kind of degenerate elliptic sys- tem of the first order equations in R4 is proposed. Then, with the help of the one-to-one correspondence between the theory of Cliffor... Firstly, the Riemann boundary value problem for a kind of degenerate elliptic sys- tem of the first order equations in R4 is proposed. Then, with the help of the one-to-one correspondence between the theory of Clifford valued generalized regular functions and that of the degenerate elliptic system's solution, the boundary value problem as stated above is trans- formed into a boundary value problem related to the generalized regular functions in Clifford analysis. Moreover, the solution of the Riemann boundary value problem for the degenerate elliptic system is explicitly described by using a kind of singular integral operator. Finally, the conditions for the existence of solutions of the oblique derivative problem for another kind of degenerate elliptic system of the first order equations in R4 are derived. 展开更多
关键词 Clifford analysis generalized regular function degenerate elliptic system Riemann boundaryvalue problem oblique derivative problem.
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The Similar Structures and Control Problems of Complex Systems 被引量:1
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作者 张嗣瀛 《系统仿真学报》 CAS CSCD 2002年第11期1455-1457,共3页
In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between t... In this paper, the naturally evolving complex systems, such as biotic and social ones, are considered. Focusing on their structures, a feature is noteworthy, i.e., the similarity in structures. The relations between the functions and behaviors of these systems and their similar structures will be studied. Owing to the management of social systems and the course of evolution of biotic systems may be regarded as control processes, the researches will be within the scope of control problems. Moreover, since it is difficult to model for biotic and social systems, it will start with the control problems of complex systems, possessing similar structures, in engineering. The obtained results show that for either linear or nonlinear systems and for a lot of control problems similar structures lead to a series of simplifications. In general, the original system may be decomposed into reduced amount of subsystems with lower dimensions and simpler structures. By virtue of such subsystems, the control problems of original system can be solved more simply. At last, it turns round to observe the biotic and social systems and some analyses are given. 展开更多
关键词 复杂系统 相似结构 可控制性
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A Multi-stage Heuristic Algorithm for Matching Problem in the Modified Miniload Automated Storage and Retrieval System of E-commerce 被引量:2
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作者 WANG Wenrui WU Yaohua WU Yingying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第3期641-648,共8页
E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can't fulfill the storage and picking d... E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can't fulfill the storage and picking demands of e-commerce sufficiently. In this paper, a modified miniload automated storage/retrieval system is designed to fit these new characteristics of e-commerce in logistics. Meanwhile, a matching problem, concerning with the improvement of picking efficiency in new system, is studied in this paper. The problem is how to reduce the travelling distance of totes between aisles and picking stations. A multi-stage heuristic algorithm is proposed based on statement and model of this problem. The main idea of this algorithm is, with some heuristic strategies based on similarity coefficients, minimizing the transportations of items which can not arrive in the destination picking stations just through direct conveyors. The experimental results based on the cases generated by computers show that the average reduced rate of indirect transport times can reach 14.36% with the application of multi-stage heuristic algorithm. For the cases from a real e-commerce distribution center, the order processing time can be reduced from 11.20 h to 10.06 h with the help of the modified system and the proposed algorithm. In summary, this research proposed a modified system and a multi-stage heuristic algorithm that can reduce the travelling distance of totes effectively and improve the whole performance of e-commerce distribution center. 展开更多
关键词 e-commerce modified miniload automated storage/retrieval system matching problem multi-stage heuristic algorithm
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Consensus problems of multi-agent systems with noise perturbation 被引量:2
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作者 孙永征 阮炯 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4137-4141,共5页
In this paper, by using the stability theory of stochastic differential equations, the average-consensus problem with noise perturbation is investigated. It is analytically proved that the consensus could be achieved ... In this paper, by using the stability theory of stochastic differential equations, the average-consensus problem with noise perturbation is investigated. It is analytically proved that the consensus could be achieved with a probability of one. Furthermore, numerical examples are taken to illustrate the effectiveness of the theoretical result. 展开更多
关键词 consensus problems multi-agent systems white noise
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The Existence and Uniqueness of Solutions to Systems of Second-order Ordinary Differential Equations Boundary Value Problem in Absract Space 被引量:2
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作者 武力兵 孙涛 何希勤 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第4期573-577,共5页
In this paper, it is discussed by using cone and upper and lower solutions mono- tone iterative theory of mixed monotone operator that the bounary value problem is more generalized style to system of equations in the ... In this paper, it is discussed by using cone and upper and lower solutions mono- tone iterative theory of mixed monotone operator that the bounary value problem is more generalized style to system of equations in the form of -u = f(t, u, v) -v = g(t, u, v) u(0) = u(1) = 0 v(0) = v(1) = 0 in abstract space. Moreover, it is obtained unique solutions for system of equations and error estimations between approximation iteration sequence and exact solution under more simpler conditions. Therefore, some new results which extend and improve the related known works in the literatures are obtained. 展开更多
关键词 systems of equations bounary value problem CONE approximation solution
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THE STABILITY OF STATIONARY SOLUTION FOR OUTFLOW PROBLEM ON THE NAVIER-STOKES-POISSON SYSTEM 被引量:3
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作者 蒋咪娜 赖素华 +1 位作者 尹海燕 朱长江 《Acta Mathematica Scientia》 SCIE CSCD 2016年第4期1098-1116,共19页
In this article, we are concerned with the stability of stationary solution for outflow problem on the Navier-Stokes-Poisson system. We obtain the unique existence and the asymptotic stability of stationary solution. ... In this article, we are concerned with the stability of stationary solution for outflow problem on the Navier-Stokes-Poisson system. We obtain the unique existence and the asymptotic stability of stationary solution. Moreover, the convergence rate of solution towards stationary solution is obtained. Precisely, if an initial perturbation decays with the algebraic or the exponential rate in space, the solution converges to the corresponding stationary solution as time tends to infinity with the algebraic or the exponential rate in time. The proof is based on the weighted energy method by taking into account the effect of the self-consistent electric field on the viscous compressible fluid. 展开更多
关键词 Navier-Stokes-Poisson system stationary solution outflow problem convergence rate weighted energy method
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THE NONLINEAR BOUNDARY VALUE PROBLEM FOR A CLASS OF INTEGRO-DIFFERENTIAL SYSTEM 被引量:1
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作者 Rongrong Tang 《Analysis in Theory and Applications》 2006年第3期254-261,共8页
In this paper, using the theory of differential inequalities, we study the nonlinear boundary value problem for a class of integro-differential system. Under appropriate assumptions, the existence of solution is prove... In this paper, using the theory of differential inequalities, we study the nonlinear boundary value problem for a class of integro-differential system. Under appropriate assumptions, the existence of solution is proved and the uniformly valid asymptotic expansions for arbitrary n-th order approximation and the estimation of remainder term are obtained simply and conveniently. 展开更多
关键词 integro-differential system nonlinear boundary value problem differential inequality
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L^p-L^q decay estimates of solutions to Cauchy problems of thermoviscoelastic systems 被引量:1
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作者 YANG Lin HUANG Li-hong KUANG Feng-lian 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期473-482,共10页
L^p- L^q decay estimate of solution to Cauchy problem of a linear thermoviscoelastic system is studied. By using a diagonalization argument of frequency analysis, the coupled system will be decoupled micrologically. T... L^p- L^q decay estimate of solution to Cauchy problem of a linear thermoviscoelastic system is studied. By using a diagonalization argument of frequency analysis, the coupled system will be decoupled micrologically. Then with the help of the information of characteristic roots for the coefficient matrix of the system, L^p- L^q decay estimate of parabolic type of solution to the Cauchy problem is obtained. 展开更多
关键词 L^p- L^q decay estimate Cauchy problem thermoviscoelastic system
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SZEBEHELY'S PROBLEM FOR NONHOLONOMICSYSTEMS WITH A GIVEN FIRST INTEGRAL
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作者 朱海平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1998年第9期843-849,共7页
An inverse problem for nonholonomic systems is studiedin. The equations of motion of nonholonomic systems are given. and the Szebehely's problem for a mechanical system with homogeneous nonholonomic cons... An inverse problem for nonholonomic systems is studiedin. The equations of motion of nonholonomic systems are given. and the Szebehely's problem for a mechanical system with homogeneous nonholonomic constraints is considered, and the generulnonholonomic systems with a given first integral are studied. 展开更多
关键词 analytical mechanics nonholonomic system inverse problem
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A NEW STATIC MECHANICS MODEL TO SOLVE CONTACT PROBLEMS IN MECHANICAL SYSTEMS
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作者 陆志华 叶庆泰 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第11期1314-1322,共9页
The coupling of the local contact problems between the components and the deformation of the components in the mechanical system were discovered.A series of coordinate systems have been founded to describe the mechani... The coupling of the local contact problems between the components and the deformation of the components in the mechanical system were discovered.A series of coordinate systems have been founded to describe the mechanical system with the contact problems.The method of isolating the boundary of contact body from others has been used to describe the constraint between the contacting points.A more generalized static mechanics model of the mechanical system with the contact problems has been founded through the principle of virtual work.As an application,the model was used to study the multi_teeth engagement problems in the inner meshed planet gear systems.The stress distribution of contact gears was got.A test has verified that the static contact model and the computational method are right. 展开更多
关键词 mechanical system contact problem planet gear drive
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EXTENDED SYSTEM, BIFURCATION PROBLEM AND HIGH ORDER SINGULARITIES
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作者 胡国庆 李开泰 《Acta Mathematica Scientia》 SCIE CSCD 1995年第1期65-73,共9页
In this paper, we consider two extended systems. When using them for the two parameter bifurcation problems, the simple bifurcation point with regard to lambda on turn into the simple turning point with. regard to mu.... In this paper, we consider two extended systems. When using them for the two parameter bifurcation problems, the simple bifurcation point with regard to lambda on turn into the simple turning point with. regard to mu. Simple high orde bifurcation point is first studied without using the symmetry condition. 展开更多
关键词 2-PARAMETER NONLINEAR problemS EXTENDED systemS BIFURCATION problem SIMPLE TURNING POINT SIMPLE HIGH ORDER BIFURCATION POINT
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