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Numerical Approach of Network Problems in Optimal Mass Transportation
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作者 Lamine Ndiaye Babacar Mbaye Ndiaye +1 位作者 Pierre Mendy Diaraf Seck 《Applied Mathematics》 2012年第5期457-466,共10页
In this paper, we focus on the theoretical and numerical aspects of network problems. For an illustration, we consider the urban traffic problems. And our effort is concentrated on the numerical questions to locate th... In this paper, we focus on the theoretical and numerical aspects of network problems. For an illustration, we consider the urban traffic problems. And our effort is concentrated on the numerical questions to locate the optimal network in a given domain (for example a town). Mainly, our aim is to find the network so as the distance between the population position and the network is minimized. Another problem that we are interested is to give an numerical approach of the Monge and Kantorovitch problems. In the literature, many formulations (see for example [1-4]) have not yet practical applications which deal with the permutation of points. Let us mention interesting numerical works due to E. Oudet begun since at least in 2002. He used genetic algorithms to identify optimal network (see [5]). In this paper we introduce a new reformulation of the problem by introducing permutations . And some examples, based on realistic scenarios, are solved. 展开更多
关键词 OPTIMAL MASS TRANSPORTATION network URBAN TRAFFIC Monge-Kantorovich problem Global Optimization
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Artificial Neural Networks Approach for Solving Stokes Problem 被引量:5
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作者 Modjtaba Baymani Asghar Kerayechian Sohrab Effati 《Applied Mathematics》 2010年第4期288-292,共5页
In this paper a new method based on neural network has been developed for obtaining the solution of the Stokes problem. We transform the mixed Stokes problem into three independent Poisson problems which by solving th... In this paper a new method based on neural network has been developed for obtaining the solution of the Stokes problem. We transform the mixed Stokes problem into three independent Poisson problems which by solving them the solution of the Stokes problem is obtained. The results obtained by this method, has been compared with the existing numerical method and with the exact solution of the problem. It can be observed that the current new approximation has higher accuracy. The number of model parameters required is less than conventional methods. The proposed new method is illustrated by an example. 展开更多
关键词 Artificial Neural networks STOKES problem POISSON Equation PARTIAL Differential EQUATIONS
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The Necessities and Problems of Multimedia and Network Teaching in Vocational College English Teaching
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作者 朱祥 《海外英语》 2011年第4X期90-91,共2页
With the development of social economy,the multimedia and network teaching is more and more important in college English teaching,especially in vocational college.It can not only help students to give full play to the... With the development of social economy,the multimedia and network teaching is more and more important in college English teaching,especially in vocational college.It can not only help students to give full play to their collective consciousness and make our English course be full of vitality,but also make the amount of information in class redoubled.For the multimedia and network teaching,there're some problems in English teaching.So the multimedia and network teaching has both necessities and problems. 展开更多
关键词 MULTIMEDIA and network technology ENGLISH TEACHING VOCATIONAL COLLEGE necessities problemS
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On the Problems of Computer Network Maintenance and Security 被引量:1
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作者 张保峰 《电子世界》 2018年第7期103-103,105,共2页
伴随我国计算机网络事业的快速发展,我们的生活已与网络紧密相联,但随着数据网络的传播,安全问题也开始出现。网络安全所涉及到的知识面较广,其中与网络安全存在着重要关联的就是计算机网络维护工作的质量。为此,本文就通过计算机... 伴随我国计算机网络事业的快速发展,我们的生活已与网络紧密相联,但随着数据网络的传播,安全问题也开始出现。网络安全所涉及到的知识面较广,其中与网络安全存在着重要关联的就是计算机网络维护工作的质量。为此,本文就通过计算机网络维护保障网络安全的具体策略展开了进一步探讨,希望能为行业发展提供一定参考。 展开更多
关键词 计算机网络 维护 安全问题 策略
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Cognitive Radio Ad-Hoc Networks: Some New Results on Multi-Channel Hidden Terminal Problem 被引量:1
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作者 Palaniandavar Venkateswaran Srishti Shaw +1 位作者 Sandhya Pattanayak Rabindranath Nandi 《Communications and Network》 2012年第4期342-348,共7页
Recently the Cognitive Radio (CR), in particular the CR Ad-Hoc Network (CRAHN) technology appears as a burgeoning area in wireless communication that enables utilization of limited network resources in more efficient ... Recently the Cognitive Radio (CR), in particular the CR Ad-Hoc Network (CRAHN) technology appears as a burgeoning area in wireless communication that enables utilization of limited network resources in more efficient and intelligent way;studies indicate that opportunistic utilization of the available radio frequency spectrum, without interfering the licensed primary user (PU) could be made. This paper presents some simulation based performance of the Multi-Channel Hidden Terminal (MCHT) problem on CRAHNs;new observations on the effect of the number of channels on certain PU-activity metrics, e.g., delay and throughput, are described. 展开更多
关键词 COGNITIVE AD-HOC networks MCHT problem WIRELESS Communication NS-2
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Wavelet network solution for the inverse kinematics problem in robotic manipulator 被引量:5
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作者 CHEN Hua CHEN Wei-shan XIE Tao 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期525-529,共5页
Wavelet network, a class of neural network consisting of wavelets, is proposed to solve the inverse kinematics problem in robotic manipulator. A wavelet network suitable for dealing with multi-input and multi-output s... Wavelet network, a class of neural network consisting of wavelets, is proposed to solve the inverse kinematics problem in robotic manipulator. A wavelet network suitable for dealing with multi-input and multi-output system is constructed. The network is optimized by reducing the number of wavelets handling large dimension problem according to the sample data. The algorithms for sparseness analysis of input data and fitting wavelets to the output data with orthogonal method are introduced. Then Levenberg-Marquardt algorithm is used to train the network. Simulation results showed that this method is capable of solving the inverse kinematics problem for PUMA560. 展开更多
关键词 小波网络 机器人 机械手 逆运动学问题
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APPLICATION OF ARTIFICIAL NEURAL NETWORK TO INVERSE PROBLEMS OF ESTIMATING INNER ETCH OF ELASTOPLASTIC PIPE UNDER PRESSURE
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作者 Guan, BT Shen, CW +1 位作者 Xiao, JS Cai, YS 《Acta Mechanica Solida Sinica》 SCIE EI 1996年第1期88-93,共6页
To determine a variation of pipe's inner geometric shape as due to etch, the three-layered feedforward artificial neural network is used in the inverse analysis through observing the elastoplastic strains of the o... To determine a variation of pipe's inner geometric shape as due to etch, the three-layered feedforward artificial neural network is used in the inverse analysis through observing the elastoplastic strains of the outer wall under the working inner pressure. Because of different kinds of inner wail radii and eccentricity. several groups of strains calculated with computational mechanics are used for the network to do learning. Numerical calculation demonstrates that this method is effective and the estimated inner wall geometric parameters have high precision. 展开更多
关键词 artificial neural network inverse problem ELASTOPLASTIC finite element
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NETWORK ANALYSIS OF EIGENVALUE PROBLEM FOR MULTILAYER DIELECTRIC WAVEGUIDE CONSISTING OF ARBITRARY NUMBER OF LAYERS
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作者 徐善驾 《Journal of Electronics(China)》 1989年第1期50-58,共9页
In this paper,the eigenvalue problem of a multilayer dielectric waveguide consisting of arbitrarynumber of layers is solved by the microwave network method.A general program with the function of com-puter graphics has... In this paper,the eigenvalue problem of a multilayer dielectric waveguide consisting of arbitrarynumber of layers is solved by the microwave network method.A general program with the function of com-puter graphics has been developed for analyzing the dispersion characteristics and the electromagnetic fielddistributions of an N layer dielectric waveguide.As an example of practical applications,the procedure ofmode conversion and mode separation in dielectric branching waveguides is vividly demonstrated throughanalyzing the field distributions of asymmetric multilayer dielectric structures and the general rules of modeconversion are discussed. 展开更多
关键词 MULTILAYER dielectric WAVEGUIDE EIGENVALUE problem network analysis
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A Water Line Network Failure Application of Network Design Problems
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作者 Hiroaki Mohri Jun-ichi Takeshita 《Journal of Mathematics and System Science》 2015年第12期493-500,共8页
关键词 网络故障 供水管道 设计问题 应用 线路 组合优化问题 紧急情况 程序实现
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Chaotic Neural Network Technique for "0-1" Programming Problems 被引量:1
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作者 王秀宏 乔清理 王正欧 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2003年第4期99-105,共7页
0-1 programming is a special case of the integer programming, which is commonly encountered in many optimization problems. Neural network and its general energy function are presented for 0-1 optimization problem. The... 0-1 programming is a special case of the integer programming, which is commonly encountered in many optimization problems. Neural network and its general energy function are presented for 0-1 optimization problem. Then, the 0-1 optimization problems are solved by a neural network model with transient chaotic dynamics (TCNN). Numerical simulations of two typical 0-1 optimization problems show that TCNN can overcome HNN's main drawbacks that it suffers from the local minimum and can search for the global optimal solutions in to solveing 0-1 optimization problems. 展开更多
关键词 neural network chaotic dynamics 0-1 optimization problem.
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Assessment of a Proposed Software Design for the Solution of Multi-Phase Mechanics Problems on Networked Laptops
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作者 Richard Harris Thomas Impelluso 《Intelligent Information Management》 2010年第7期391-397,共7页
This paper presents the design of a computational software system that enables solutions of multi-phase and multi-scale problems in mechanics. It demonstrated how mechanicians can design “process-driven” software sy... This paper presents the design of a computational software system that enables solutions of multi-phase and multi-scale problems in mechanics. It demonstrated how mechanicians can design “process-driven” software systems directly, and that such efforts are more suitable in solving multi-phase or multi-scale problems, rather than utilizing the “data-driven” approaches of legacy network systems. Specifically, this paper demonstrates how this approach can be used to solve problems in flexible dynamics. Then it suggests a view of mechanics algorithms as ‘state equilibrium’ enforcers residing as servers, rather than as computer programs that solve field equations. It puts forth the need for identical input/output files to ensure widespread deployment on laptops. Then it presents an assessment of the laptop platform. A software system such as the one presented here can also be used to supply virtual environments, animations and entertainment/education software with physics. 展开更多
关键词 SOFTWARE Design MULTI-PHASE MECHANICS problemS networkED LAPTOPS
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Unsupervised neural network model optimized with evolutionary computations for solving variants of nonlinear MHD Jeffery-Hamel problem 被引量:1
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作者 M.A.Z.RAJA R.SAMAR +1 位作者 T.HAROON S.M.SHAH 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第12期1611-1638,共28页
A heuristic technique is developed for a nonlinear magnetohydrodynamics (MHD) Jeffery-Hamel problem with the help of the feed-forward artificial neural net- work (ANN) optimized with the genetic algorithm (GA) a... A heuristic technique is developed for a nonlinear magnetohydrodynamics (MHD) Jeffery-Hamel problem with the help of the feed-forward artificial neural net- work (ANN) optimized with the genetic algorithm (GA) and the sequential quadratic programming (SQP) method. The twodimensional (2D) MHD Jeffery-Hamel problem is transformed into a higher order boundary value problem (BVP) of ordinary differential equations (ODEs). The mathematical model of the transformed BVP is formulated with the ANN in an unsupervised manner. The training of the weights of the ANN is carried out with the evolutionary calculation based on the GA hybridized with the SQP method for the rapid local convergence. The proposed scheme is evaluated on the variants of the Jeffery-Hamel flow by varying the Reynold number, the Hartmann number, and the an- gles of the walls. A large number of simulations are performed with an extensive analysis to validate the accuracy, convergence, and effectiveness of the scheme. The comparison of the standard numerical solution and the analytic solution establishes the correctness of the proposed designed methodologies. 展开更多
关键词 Jeffery-Hamel problem neural network genetic algorithm (GA) nonlinear ordinary differential equation (ODE) hybrid technique sequential quadratic programming
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The Budget Constrained Multi-product Newsboy Problem with Reactive Production:A Problem from Entrepreneurial Network Construction
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作者 LI WEN-JIN PANG YAN-NI 《Communications in Mathematical Research》 CSCD 2012年第2期97-107,共11页
This paper develops an extended newsboy model and presents a formula- tion for this model. This new model has solved the budget contained multi-product newsboy problem with the reactive production. This model can be u... This paper develops an extended newsboy model and presents a formula- tion for this model. This new model has solved the budget contained multi-product newsboy problem with the reactive production. This model can be used to describe the status of entrepreneurial network construction. We use the Lagrange multiplier procedure to deal with our problem, but it is too complicated to get the exact solu-tion. So we introduce the homotopy method to deal with it. We give the flow chart to describe how to get the solution via the homotopy method. We also illustrate our model in both the classical procedure and the homotopy method. Comparing the two methods, we can see that the homotopy method is more exact and efficient. 展开更多
关键词 newsboy problem entrepreneurial network construction multi-product budget constrained reactive production homotopy method
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Analysis on the Current Situation and Problems of Network Construction for Overseas Chinese Affairs Service
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作者 WEN Qiuhua 《International English Education Research》 2016年第2期37-39,共3页
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Using Heuristics to the Controller Placement Problem in Software-Defined Multihop Wireless Networking
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作者 Afsane Zahmatkesh Chung-Horng Lung 《Communications and Network》 2020年第4期199-219,共21页
Solving the controller placement problem (CPP) in an SDN architecture with multiple controllers has a significant impact on control overhead in the network, especially in multihop wireless networks (MWNs). The generat... Solving the controller placement problem (CPP) in an SDN architecture with multiple controllers has a significant impact on control overhead in the network, especially in multihop wireless networks (MWNs). The generated control overhead consists of controller-device and inter-controller communications to discover the network topology, exchange configurations, and set up and modify flow tables in the control plane. However, due to the high complexity of the proposed optimization model to the CPP, heuristic algorithms have been reported to find near-optimal solutions faster for large-scale wired networks. In this paper, the objective is to extend those existing heuristic algorithms to solve a proposed optimization model to the CPP in software-<span>defined multihop wireless networking</span><span> (SDMWN).</span>Our results demonstrate that using ranking degrees assigned to the possible controller placements, including the average distance to other devices as a degree or the connectivity degree of each placement, the extended heuristic algorithms are able to achieve the optimal solution in small-scale networks in terms of the generated control overhead and the number of controllers selected in the network. As a result, using extended heuristic algorithms, the average number of hops among devices and their assigned controllers as well as among controllers will be reduced. Moreover, these algorithms are able tolower<span "=""> </span>the control overhead in large-scale networks and select fewer controllers compared to an extended algorithm that solves the CPP in SDMWN based on a randomly selected controller placement approach. 展开更多
关键词 Software-defined Multihop Wireless networking (SDMWN) Controller Placement problem (CPP) Control Overhead Heuristic Algorithms
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Solution of Inverse Problem on Distributed Generation Using Complex-Valued Network Inversion
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作者 Takehiko Ogawa Kyosuke Nakamura 《Journal of Mechanics Engineering and Automation》 2011年第6期436-444,共9页
关键词 分布式发电系统 复数神经网络 逆问题 反演 扩展网络 观测数据 能源植物 能源领域
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A Study of Optimum Switching Problem for Production Systems Considering Efficiency, Delivery Time and Green Evaluation
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作者 Jing Sun Mingjuan Zhao +1 位作者 Akihiro Yano Hisashi Yamamoto 《Journal of Computer and Communications》 2023年第2期158-171,共14页
This paper aims to derive the optimal switching strategy for production system considering efficiency, delivery time and green evaluation. Nowadays more and more manufacturing and logistics systems not only pursue bet... This paper aims to derive the optimal switching strategy for production system considering efficiency, delivery time and green evaluation. Nowadays more and more manufacturing and logistics systems not only pursue better work efficiency, but also focus on green energy evaluation issues. Cost reduction and shortening of delivery time are always important management issues in pursuit of efficiency and optimization of the entire production system because of global production competition. In a market situation where customer needs change in various ways, in particular, due to inadequate quality, changes in the local environment, natural disasters and so on. Therefore, prompt planning of management measures such as switching work processes and changing production methods has become an important issue. On the other hand, since the Paris Agreement came into effect, the construction of an environment-friendly production system has been required as an approach to environmental problems such as global warming. In this paper, we propose an optimum switching model of production systems considering efficiency, delivery time and green evaluation using a green evaluation index (GEC: Green Energy Coefficient). We also discuss the optimal switching strategy by numerical observation. 展开更多
关键词 Green Evaluation Sustainable Production Optimal Switching problem Production networks Decarbonization Manufacture Management
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RECURRENT NEURAL NETWORK MODEL BASED ON PROJECTIVE OPERATOR AND ITS APPLICATION TO OPTIMIZATION PROBLEMS
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作者 马儒宁 陈天平 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第4期543-554,共12页
The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed con... The recurrent neural network (RNN) model based on projective operator was studied. Different from the former study, the value region of projective operator in the neural network in this paper is a general closed convex subset of n-dimensional Euclidean space and it is not a compact convex set in general, that is, the value region of projective operator is probably unbounded. It was proved that the network has a global solution and its solution trajectory converges to some equilibrium set whenever objective function satisfies some conditions. After that, the model was applied to continuously differentiable optimization and nonlinear or implicit complementarity problems. In addition, simulation experiments confirm the efficiency of the RNN. 展开更多
关键词 recurrent neural network model projective operator global convergence OPTIMIZATION complementarity problems
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Components Assignment Problem for Multi-Source Multi-Sink Flow Networks with Reliability and Budget Constraints
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作者 Noha Nasr Elden Moatamad Hassan Mohamed Abd El-Aziz 《Journal of Computer and Communications》 2022年第6期99-111,共13页
System reliability optimization problem of multi-source multi-sink flow network is defined by searching the optimal components that maximize the reliability and minimize the total assignment cost. Therefore, a genetic... System reliability optimization problem of multi-source multi-sink flow network is defined by searching the optimal components that maximize the reliability and minimize the total assignment cost. Therefore, a genetic-based approach is proposed to solve the components assignment problem under budget constraint. The mathematical model of the optimization problem is presented and solved by the proposed genetic-based approach. The proposed approach is based on determining the optimal set of lower boundary points that maximize the system reliability such that the total assignment cost does not exceed the specified budget. Finally, to evaluate our approach, we applied it to various network examples with different numbers of available components;two-source two-sink network and three-source two-sink network. 展开更多
关键词 Multi-Source Multi-Sink Stochastic-Flow networks System Reliability Optimization Components Assignment problem
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Tackling Key Technological Problems and Advancing 5G Technology Application in Railway
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作者 ZHOU Li ZHENG Mingda 《Chinese Railways》 2023年第1期3-12,共10页
The paper summarizes the development of mobile communication of domestic and foreign railways,and proposes the priorities for tackling key technological problems of railway 5G private network according to the technica... The paper summarizes the development of mobile communication of domestic and foreign railways,and proposes the priorities for tackling key technological problems of railway 5G private network according to the technical routes of railway next-generation mobile communication determined by China State Railway Group Co.,Ltd.From the aspects of work objectives,principles,technical routes and innovative working methods,the paper elaborates the ideas of railway 5G scientific and technological research,puts forward the contents and plans of scientific and technological research on railway 5G private network,systematically organizes the achievements in the scientific and technological research stage of railway 5G private network,and sets forth the key contents of next-step scientific and technological research. 展开更多
关键词 railway mobile communication system railway 5G private network tackling key problems in science and technology on 5G private network
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