Fault-tolerant expansion of system area networks in multiprocessor computer systems

A method for constructing a fault-tolerant system area network in the form of a flat network consisting of several copies of the original network is proposed. The flat network is constructed according to the theory of incomplete balanced block designs.     

Application of the majority connectedness carrier for computing the reliability of complex systems

A computational method for probability of majority connectedness of the two-pole network of a random graph is stated when the union of circuits is used as a connectedness carrier of node-poles. Formal rules for calculations of this type illustrated by the corresponding examples are given.     

On the solution of the traveling salesman problem once again

The procedure is suggested for the construction of Hamiltonian cycles optimized along the length in weighted graphs by the method of the stagewise isolation and lengthening of the linear portions of paths of the minimized length. The procedure makes it possible to process both nonoriented and oriented graphs, i.e., to solve symmetric and nonsymmetric problems of the traveling salesman. At each stage of the procedure (starting from the first stage), the subgraphs of the initial (original) graph of the problem are processed, the complexity of which decreases in the transitions from stage to stage. The isolation and the lengthening of linear portions of the paths are the simplest operations for the detection of vertices of degree 2 with the possible removal of some edges (arcs) of a subgraph. These characteristics of the procedure (the stagewise decrease of the complexity of the processable subgraphs and the exceptional simplicity of operations for the isolation and lengthening of the linear portions of paths) permits us to hope for a high effectiveness of the use of the procedure for the solution of the traveling salesman problems of large dimensions.     

Routing control in IP-networks with the variable performance criterion

For routing control in backbone IP-networks, we propose to part the control time interval into two segments and to use different performance criteria on them. It is assumed that distribution of flows is realized at the first step by the Dijkstra algorithm which is included in OSPF and is used in Sisco routers. The minimax criterion is proposed at the second step; it is realized in the robust algorithm of data incoming flows distribution adjustment. The object of the adjustment algorithm is to prevent or lower the probability of networks congestion. Characteristics of the proposed algorithm are studied. Efficiency of the adjustment algorithm application for network controlling is demonstrated by the Monte Carlo method. Speed characteristics of the proposed algorithm are compared with some optimal algorithms.     

Enhanced-robustness Dijkstra algorithm for control of routing in the IP-networks

A modified Dijkstra algorithm which is an efficient tool for allocation of the input data flows in the backbone IP-networks using the OSPF protocol was proposed. The purpose of modification was to improve the algorithm robustness to the overloads in the data networks. Numerous experimental comparisons of the performance of the proposed algorithm and the linear programming-based algorithm of robust load correction and allocation in the IP-networks demonstrated that the proposed algorithm is highly efficient.     

Investigation and application of Laplace spectra of orgraphs with the ring structure

The Laplace matrix is a square matrix L = (? _ij ) ∈ ? ^n×n in which all nondiagonal elements are nonpositive and all row sums are equal to zero. Each Laplace matrix corresponds to a weighted orgraph with positive arc weights. The problem of reality of Laplace matrix spectrum for orgraphs of a special type consisting of two “counter” Hamiltonian cycles in one of which one or two arcs are removed is studied. Characteristic polynomials of Laplace matrices of these orgraphs are expressed through polynomials Z _n (x) that can be obtained from Chebyshev second-kind polynomials P _2n (y) by the substitution of y ² = x. The obtained results relate to properties of the product of Chebyshev second-kind polynomials. A direct method for computing the spectrum of Laplace circuit matrix is given. The obtained results can be used for computing the number of spanning trees in orgraphs of the studied type. One of the possible practical applications of these results is the investigation of topology and development of new Internet protocols.     

Topological optimization of the large-scale data transmission networks

Consideration was given to the design of the topological structure of the doubly connected large-scale networks by the cost criterion and constraints on the diameter. An exact combinatorial algorithm to solve the problem and a parallel algorithm to carry out calculations on the multiprocessor data-flow computer system were proposed. Parallelization was shown to provide a substantial gain in the time of computations in the optimal topological structure of the large-scale networks.     

Organization of self-diagnosis of the discrete multicomponent systems a structure like bipartite quasicomplete graphs

Organization of an efficient self-diagnosis of the multicomponent computer and communication systems of diverse structures always attracted attention of the researchers and engineers. A method to solve these problems is presented in the paper by way of the example of a system whose structure is modeled by a uniform ordinary bipartite graph of diameter d = 3, any degree s > 1, and any number n of vertices, where n = s(s ? 1) + 1. The method requires checking of (s ? 1)³ graph loops of length eight each, which is smaller than the number s ²(s ? 1) + s of checks of single graph edges.     

工作流管理系统的流程柔性动态变更研究

为解决工作流管理系统中流程柔性演进变化问题,结合业务模型生命周期和业务流程模型变更管理的特点,提出了一个支持业务流程动态更新模型和业务流程实例动态迁移算法。在该算法中引入区域划分法,在迁移之前进行相关数据一致性检查和影响区域比较,通过该算法实现流程实例动态调整,以适应新的变种。最后基于该算法和一工作流管理系统平台,通过一个案例来演示业务流程动态更新的过程。     

一种灌装过程计算机动态仿真系统的开发

简要剖析了液态化学品灌装工艺流程及其灌装原理,应用物料平衡、气体状态方程和过程技术数据,通过微分方程法和动态补偿法等方法建立灌装过程动态仿真数学模型.基于单机智能控制(intelligent process control,IPC)仿真模式,应用自控组态软件Centrey Star,研究了过程的动态仿真实现方法,确定了仿真系统的总体结构组成、总体技术方案与原理,开发了仿真系统的图形用户操作界面,完成了仿真工艺流程图、各类仿真命令按钮及其显示画面、以及流程中各类可操作部件及其参数调整仿真操作画面的设计与命令语言编程,用Visual C++(VC++)开发了模型运算软件,生成了DLL库函数,与图形用户界面集成,研制了一套完备的动态仿真系统,实现了灌装工艺过程的全面动态仿真.最后系统地进行了灌装过程的原理性仿真试验,获得了满意的仿真结果,优化了灌装过程工艺运行条件.     

On the polynomial dynamic system approach to software development

1IntroductionReactivesystemsareregardedessentialintheareaofcomputerscience[1].Quiteafewapproacheshavebeenproposedtodevelopreactivesystems,includingthestatemateapproach[2],thetemporal-logicapproach[3],thesynchronousapproach[4],amongoth-ers[5,6].Usually,thepropertiesofthereactivesoftwareunderdevelopmentarecheckedaposteriori(aftersoftwaredesignorevensoftwareimplementation)usingpropertyveri-ficationand/orsimulationtechniquessuchasthetemporal-logicapproach[7]andtheSmoochesapproach[5].However,thisi…     

引领自动化领域发展潮流 带动智能产业不断升级变革

<正>在2010中国国际工业博览会上,本刊记者有幸见到了携最新技术和理念参会的研华自动化事业群产品部经理阮北山先生和中国区产品项目经理蔡勤女士,见到北山先生的感觉就像研华产品一样可靠、可信赖。蔡勤女士的果敢干练也给     

浅谈自动化技术在电力系统的应用和发展趋势

自动化技术在电力系统中的应用极大地保障了电网运行的稳定性、安全性和经济性,提高了电网运行的效率,保证了电能质量,对电力系统的发展有着深远的影响。介绍了电力系统自动化的基本内容和其重要性,分析了自动化技术在电力系统中的发展趋势。     

Mutual fund competition in the presence of dynamic flows

This paper analyzes competition between mutual funds in a multiple funds version of the model of Hugonnier and Kaniel (2010). We characterize the set of equilibria for this portfolio management game and show that there exists a unique Pareto optimal equilibrium. The main result of this paper shows that the funds cannot differentiate themselves through portfolio choice in the sense that they should offer the same risk/return tradeoff in equilibrium. This result brings theoretical support to the findings of recent empirical studies on the importance of media coverage and marketing in the mutual funds industry.     

Computer consultants' views of user participation in the system development process

The form of user participation adopted in any system development process is commonly argued to be an important determinant of its outcome. This study investigated computer consultants' experiences and views of different forms of user participation in the system development process. Thirty-four consultants from 14 Swedish companies of three different sizes filled out a questionnaire (response rate 47%). The results indicated that the consultants viewed both external factors and their own roles as guiding the degree of user participation. The consultants reported that reference groups, seminars/meetings and user testing were common forms of user participation in projects introducing existing programs into organizations and that seminars/meetings, users in project groups and reference groups, were the most common user participation forms in projects developing new programs for an organization. In both contexts, user testing was reported to be most common in the operation/administration phase of the project. The majority of consultants considered union participation to be fairly unimportant. Further, it was found that questionnaires were seldom used for data collection in projects. Finally, the consultants did not appear to categorize development projects by the type of user participation employed in the projects.     

ADI在数据采集系统领域的新技术与发展趋势

<正>数据采集系统是对传感器或所需测量或处理信号进行采集、数字化、存储、分析和显示的一个完整信号处理链路。图1是一个典型的数据采集系统。     

Multi agent architecture for dynamic incremental process planning in the flexible manufacturing system

Due to rapid changes of markets and pressures of competitions, industries are adopting their production ways to support diversity of customer’s needs and increase of new product developments. This paper deals with development of an agent-based architecture of dynamic systems for process planning in the manufacturing systems. In consideration of alternative manufacturing processes and machine tools, the process plans and the schedules of the manufacturing resources are generated incrementally and dynamically. A previously proposed negotiation protocol is customized and improved to generate suitable process plans for the target products real-timely and dynamically, based on the alternative manufacturing processes. The alternative manufacturing processes are presented by the process plan networks and the suitable process plans are searched and generated to cope with both the dynamic status and disturbances of the manufacturing systems. We initiatively combine the heuristic search algorithms of the process plan networks with the negotiation protocols, in order to generate suitable process plans.     

A model of the software development process

This paper presents a model of the programming process. The model has four parts. A resources model specifies how many useful man-months of design effort are available from project team members after subtracting the time required for learning and team communications. A system design model specifies how many man-months of effort are required to derive program module specifications, as a function of the number of team members, program size, and number of modules. A coding model specifies how many man-months of effort are required for coding, as a function of team, module, and program size. Finally, a checkout model specifies how many man-months are required for checkout as a function of program size, error detection and correction rates, and a design-complete factor. The model as a whole predicts that programmer productivity will decrease as project team size is increased and that project duration will first decrease and then increase as team size is increased. It also shows that productivity and project duration vary enormously as a function of project management factors, even when project complexity and programming staff competence are held constant.