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A Pre-Selection-Based Ant Colony System for Integrated Resources Scheduling Problem at Marine Container Terminal
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作者 Rong Wang Xinxin Xu +2 位作者 Zijia Wang Fei Ji Nankun Mu 《Computers, Materials & Continua》 SCIE EI 2024年第8期2363-2385,共23页
Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation pe... Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics system.However,the efficiency of resource scheduling significantly influences the operation performance of MCT.To solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm design.Firstly,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated RSP.The new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the objective.Secondly,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection strategy.On the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible solutions.On the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality solution.To evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is conducted.Experimental results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms. 展开更多
关键词 Resource scheduling problem(RSP) ant colony system(ACS) marine container terminal(MCT) pre-selection strategy
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一个基于WEB的跨地域沟通系统—IBM公司的Transllation Problem Report System实例分析
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作者 徐明磊 许一震 《管理工程学报》 CSSCI 2002年第B10期167-170,共4页
跨地域项目管理所遇到的最主要问题是沟通的困难,Web的广泛运用为跨地域项目管理的沟通提供了一种新的渠道。IBM公司的TPRS(Translation Problem Reprt System)便是一个基于Web的旨在提高软件翻译等跨地域项目沟通效果的系统。本文介绍... 跨地域项目管理所遇到的最主要问题是沟通的困难,Web的广泛运用为跨地域项目管理的沟通提供了一种新的渠道。IBM公司的TPRS(Translation Problem Reprt System)便是一个基于Web的旨在提高软件翻译等跨地域项目沟通效果的系统。本文介绍TPRS系统的运用实例,并在此基础上分析了其主要的功能和特点即人员和信息的分组、信息的发布与获取、注册和权限管理、定制手段、问题追踪和电子邮件通知选项,最后剖析了该系统的不足之处,以期对同类型系统的设计有所启发和帮助。 展开更多
关键词 WEB IBM公司 TRANSLATION problem Reprot system 实例分析 项目管理 系统设计 系统类型
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A Class of Nonlocal Boundary Value Problems for Elliptic Systems in Unbounded Domains
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作者 莫嘉琪 张汉林 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期29-33,共5页
A class of nonlocal boundary value probl em s for elliptic systems in the unbounded domains are considered. Under suitable c onditions, the existence of solution and the comparison theorem for the boundary value prob... A class of nonlocal boundary value probl em s for elliptic systems in the unbounded domains are considered. Under suitable c onditions, the existence of solution and the comparison theorem for the boundary value problems are studied. 展开更多
关键词 elliptic system boundary value problem c omparison theorem
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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:17
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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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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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SYSTEM OF GENERALIZED VECTOR QUASI-EQUILIBRIUM PROBLEMS ON PRODUCT FC-SPACES 被引量:5
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2007年第3期522-534,共13页
By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equi... By applying a maximal element theorem on product FC-space due to author, some new equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in FC-spaces. By using these equilibrium existence theorems, some new existence theorems of solutions for the system of generalized vector quasi-equilibrium problems are established in noncompact product FC-spaces. These results improve and generalize some recent results in literature to product FC-spaces without any convexity structure. 展开更多
关键词 Maximal element generalized game equilibrium system of generalized vector quasi-equilibrium problems FC-spaces
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Multi-type ant system algorithm for the time dependent vehicle routing problem with time windows 被引量:14
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作者 DENG Ye ZHU Wanhong +1 位作者 LI Hongwei ZHENG Yonghui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第3期625-638,共14页
The time dependent vehicle routing problem with time windows(TDVRPTW) is considered. A multi-type ant system(MTAS) algorithm hybridized with the ant colony system(ACS)and the max-min ant system(MMAS) algorithm... The time dependent vehicle routing problem with time windows(TDVRPTW) is considered. A multi-type ant system(MTAS) algorithm hybridized with the ant colony system(ACS)and the max-min ant system(MMAS) algorithms is proposed. This combination absorbs the merits of the two algorithms in solutions construction and optimization separately. In order to improve the efficiency of the insertion procedure, a nearest neighbor selection(NNS) mechanism, an insertion local search procedure and a local optimization procedure are specified in detail. And in order to find a balance between good scouting performance and fast convergence rate, an adaptive pheromone updating strategy is proposed in the MTAS. Computational results confirm the MTAS algorithm's good performance with all these strategies on classic vehicle routing problem with time windows(VRPTW) benchmark instances and the TDVRPTW instances, and some better results especially for the number of vehicles and travel times of the best solutions are obtained in comparison with the previous research. 展开更多
关键词 multi-type ant system(MTAS) time dependent vehicle routing problem with time windows(VRPTW) nearest neighbor selection(NNS)
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Layout problem of multi-component systems arising for improving maintainability 被引量:5
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作者 罗旭 杨拥民 +2 位作者 葛哲学 温熙森 官凤娇 《Journal of Central South University》 SCIE EI CAS 2014年第5期1833-1841,共9页
To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainabili... To improve the mainlainability design efficiency and quality, a layout optimization method for maintainability of multi-component systems was proposed. The impact of the component layout design on system maintainability was analyzed, and the layout problem for maintainability was presented. It was formulated as an optimization problem, where maintainability, layout space and distance requirement were formulated as objective functions. A multi-objective particle swarm optimization algorithm, in which the constrained-domination relationship and the update strategy of the global best were simply modified, was then used to obtain Pareto optimal solutions for the maintainability layout design problem. Finally, application in oxygen generation system of a spacecraft was studied in detail to illustrate the effectiveness and usefulness of the proposed method. The results show that the concurrent maintainability design can be carried out during the layout design process by solving the layout optimization problem for maintainability. 展开更多
关键词 MAINTAINABILITY layout problem OPTIMIZATION multi-component system multi-objective particle swarm optimization
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Solving material distribution routing problem in mixed manufacturing systems with a hybrid multi-objective evolutionary algorithm 被引量:7
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作者 高贵兵 张国军 +2 位作者 黄刚 朱海平 顾佩华 《Journal of Central South University》 SCIE EI CAS 2012年第2期433-442,共10页
The material distribution routing problem in the manufacturing system is a complex combinatorial optimization problem and its main task is to deliver materials to the working stations with low cost and high efficiency... The material distribution routing problem in the manufacturing system is a complex combinatorial optimization problem and its main task is to deliver materials to the working stations with low cost and high efficiency. A multi-objective model was presented for the material distribution routing problem in mixed manufacturing systems, and it was solved by a hybrid multi-objective evolutionary algorithm (HMOEA). The characteristics of the HMOEA are as follows: 1) A route pool is employed to preserve the best routes for the population initiation; 2) A specialized best?worst route crossover (BWRC) mode is designed to perform the crossover operators for selecting the best route from Chromosomes 1 to exchange with the worst one in Chromosomes 2, so that the better genes are inherited to the offspring; 3) A route swap mode is used to perform the mutation for improving the convergence speed and preserving the better gene; 4) Local heuristics search methods are applied in this algorithm. Computational study of a practical case shows that the proposed algorithm can decrease the total travel distance by 51.66%, enhance the average vehicle load rate by 37.85%, cut down 15 routes and reduce a deliver vehicle. The convergence speed of HMOEA is faster than that of famous NSGA-II. 展开更多
关键词 material distribution routing problem multi-objective optimization evolutionary algorithm local search
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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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RIEMANN-HILBERT PROBLEMS OF A SIX-COMPONENT MKDV SYSTEM AND ITS SOLITON SOLUTIONS 被引量:3
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作者 Wen-Xiu MA 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期509-523,共15页
Based on a 4 x 4 matrix spectral problem, an AKNS soliton hierarchy with six potentials is generated. Associated with this spectral problem, a kind of Riemann-Hilbert problems is formulated for a six-component system ... Based on a 4 x 4 matrix spectral problem, an AKNS soliton hierarchy with six potentials is generated. Associated with this spectral problem, a kind of Riemann-Hilbert problems is formulated for a six-component system of mKdV equations in the resulting AKNS hierarchy. Soliton solutions to the considered system of coupled mKdV equations are computed, through a reduced Riemann-Hilbert problem where an identity jump matrix is taken. 展开更多
关键词 INTEGRABLE HIERARCHY RIEMANN-HILBERT problem SOLITON solution
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Nonsmooth Equations of K-T Systems for a Constrained Minimax Problem 被引量:5
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作者 Gao Yan School of Management, University of Shanghai for Science and Technology, Shanghai 200093, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第2期31-35,共5页
Using K-T optimality condition of nonsmooth optimization, we establish two equivalent systems of the nonsmooth equations for the constrained minimax problem directly. Then generalized Newton methods are applied to so... Using K-T optimality condition of nonsmooth optimization, we establish two equivalent systems of the nonsmooth equations for the constrained minimax problem directly. Then generalized Newton methods are applied to solve these systems of the nonsmooth equations. Thus a new approach to solving the constrained minimax problem is developed. 展开更多
关键词 OPTIMIZATION Minimax problems Nonsmooth equations Generalized Newton methods.
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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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Fractional Action-Like Variational Problem and Its Noether Symmetries for a Nonholonomic System 被引量:3
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作者 张毅 龙梓轩 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2015年第4期380-389,共10页
For an in-depth study on the symmetric properties for nonholonomic non-conservative mechanical systems,the fractional action-like Noether symmetries and conserved quantities for nonholonomic mechanical systems are stu... For an in-depth study on the symmetric properties for nonholonomic non-conservative mechanical systems,the fractional action-like Noether symmetries and conserved quantities for nonholonomic mechanical systems are studied,based on the fractional action-like approach for dynamics modeling proposed by El-Nabulsi.Firstly,the fractional action-like variational problem is established,and the fractional action-like Lagrange equations of holonomic system and the fractional action-like differential equations of motion with multiplier for nonholonomic system are given;secondly,according to the invariance of fractional action-like Hamilton action under infinitesimal transformations of group,the definitions and criteria of fractional action-like Noether symmetric transformations and quasi-symmetric transformations are put forward;finally,the fractional action-like Noether theorems for both holonomic system and nonholonomic system are established,and the relationship between the fractional action-like Noether symmetry and the conserved quantity is given. 展开更多
关键词 nonholonomic system fractional action-like variational problem symmetric transformation Noether theorem conserved quantity
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Applying memetic algorithm-based clustering to recommender system with high sparsity problem 被引量:2
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作者 MARUNG Ukrit THEERA-UMPON Nipon AUEPHANWIRIYAKUL Sansanee 《Journal of Central South University》 SCIE EI CAS 2014年第9期3541-3550,共10页
A new recommendation method was presented based on memetic algorithm-based clustering. The proposed method was tested on four highly sparse real-world datasets. Its recommendation performance is evaluated and compared... A new recommendation method was presented based on memetic algorithm-based clustering. The proposed method was tested on four highly sparse real-world datasets. Its recommendation performance is evaluated and compared with that of the frequency-based, user-based, item-based, k-means clustering-based, and genetic algorithm-based methods in terms of precision, recall, and F1 score. The results show that the proposed method yields better performance under the new user cold-start problem when each of new active users selects only one or two items into the basket. The average F1 scores on all four datasets are improved by 225.0%, 61.6%, 54.6%, 49.3%, 28.8%, and 6.3% over the frequency-based, user-based, item-based, k-means clustering-based, and two genetic algorithm-based methods, respectively. 展开更多
关键词 memetic algorithm recommender system sparsity problem cold-start problem clustering method
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:4
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作者 DINGXie-ping 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2004年第6期618-626,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 family of set-valued mapping nonempty intersection theorem system of generalized vector equilibrium problem product G-convex space
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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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Existence Theory for Single and Multiple Positive Solutions to Singular Boundary Value Problems for Second-order Differential Systems P-Laplacian 被引量:4
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作者 ZHAO Xia HU Wei-min JIANG Da-qing 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第3期345-354,共10页
In this paper we present some new existence results for singular boundary value problems by Arzela-Ascoli theorem. In particular our nonlinearity may be singular in its dependent variable.
关键词 SINGULAR existence boundary value problem fixed point theorem in cones Arzela-Ascoli theorem
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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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