STATE SPACE TREE METHOD AND EXACT DECOMPOSITION ALGORITHM FOR FINDING NETWORK OVERALL RELIABILITY

First,the state space tree method for finding communication network overall re-liability is presented.It directly generates one disjoint tree multilevel polynomial of a networkgraph.Its advantages are smaller computational effort(its computing time complexity is O(en_l),where e is the number of edges and n_l is the number of leaves)and shorter resulting expression.Second,based on it an exact decomposition algorithm for finding communication network overallreliability is presented by applying the hypergraph theory.If we use it to carry out the m-timedecomposition of a network graph,the communication network scale which can be analyzed by acomputer can be extended to m-fold.     

OBDD-based network reliability calculation

An efficient method for evaluating the terminal-pair reliability based on an edge expansion tree and using an OBDD (ordered binary decision diagram) is presented. The effectiveness of the algorithm is demonstrated on the larger benchmarks collected in previous work. One notable case of the experimental results for a 2×20 lattice network is that the number of nodes in the OBDD is linearly proportional to the number of stages. This is significantly superior to previous algorithms which are based on the sum of disjoint products and has exponential complexity     

Hypermedia and network reliability

A simple algorithm utilizing the factoring theorem and other elementary network reductions is available to determine network reliability in a number of different forms. This paper describes a computer-based implementation of such an algorithm housed in a hypermedia environment. The environment can provide for both the formulation and the solution of reliability problems. In our treatment the user draws the network interactively on the computer screen and clicks an on-screen button to perform the reliability analysis. This provides an alternative to manual calculations that become tedious or impossible with networks which are neither series-parallel nor extremely small.     

Sequential evaluation of terminal pair reliability in a reliability network

For a non-series-parallel reliability network, the terminal pair reliability is evaluated sequentially and the model is extended to consider the possibility of improving the reliability of a link by a parallel duplication.     

Inflection points for network reliability

Given a finite, undirected graph G (possibly with multiple edges), we assume that the vertices are operational, but the edges are each independently operational with probability p. The (all-terminal) reliability, \(\operatorname{Rel}(G,p)\) , of G is the probability that the spanning subgraph of operational edges is connected. It has been conjectured that reliability functions have at most one point of inflection in (0,1). We show that the all-terminal reliability of almost every simple graph of order n has a point of inflection, and there are indeed infinite families of graphs (both simple and otherwise) with more than one point of inflection.     

多媒体网络可靠性分析系统实现

基于MDI的视频质量分析模型,设计并实现了多媒体网络可靠性分析系统。首先,基于RTP/RTCP协议,实现了多媒体网络视频的实时远程传输及播放。然后,将多媒体网络的视频主观评价方法与客观评价方法相结合,提出了一种综合可靠性评价方法,相较于目前的网络可靠性分析方法,综合可靠性评价方法更加全面、可信。最后,通过实验给出了可靠性分析系统的结果。     

通信网可靠性综合评估

影响通信网的可靠性因素很多。在考虑多个测度指标的情况下,通信网可靠性评估是多指标的综合评价,提出了三种综合评估方法。其中基于神经网络的综合评判较好地解决了综合评价指标中各指标的权数确定又尽可能地排除了人为因素的影响这一难题。     

刍议计算机网络的可靠性提高措施

本文主要简单的介绍了计算机网络可靠性的相关内容,通过对影响计算机网络可靠性的因素进行分析,来探讨提高计算机网络可靠性的有效措施,以保障计算机网络的安全性。据此,有利于充分发挥计算机网络的功能,确保计算机网络的正常运行,降低计算机网络的安全风险,使其具有稳定性,提升我国计算机网络市场的竞争能力,从而推动我国计算机网络的可持续发展,为计算机网络的可靠性提供重要的保障。     

OBDD-based evaluation of k-terminal network reliability

An efficient approach to determining the reliability of an undirected k-terminal network based on 2-terminal reliability functions is presented. First, a feasible set of (k-1) terminal-pairs is chosen, and the 2-terminal reliability functions of the (k-1) terminal-pairs are generated based on the edge expansion diagram using an OBDD (ordered binary decision diagram). Then the k-terminal reliability function can be efficiently constructed by combining these (k-1) reliability expressions with the Boolean and operation. Because building 2-terminal reliability functions and reducing redundant computations by merging reliability functions can be done very efficiently, the proposed approaches are much faster than those which directly expand the entire network or directly factor the k-terminal networks. The effectiveness of this approach is demonstrated by performing experiments on several large benchmark networks. An example of appreciable improvement is that the evaluation of the reliability of a source-terminal 3/spl times/10 all-terminal network took only 2.4 seconds on a SPARC 20 workstation. This is much faster than previous factoring-algorithms.     

基于决策树的软件可靠性模型选择

软件可靠性建模是软件可靠性评估的主要方法之一。现在还没有一个可适用于所有软件项目的通用模型,所以可靠性模型的选择已成为一个重要的研究方向。决策树是数据挖掘的一种算法。文中首先介绍数据挖掘与软件可靠性模型选择的结合应用概念,然后重点分析决策树的生成算法。最后以一组数据仿真决策树生成过程,并验证此方法的可行性和准确性。     

无线传感器网络可靠性建模方法

无线传感器网络部署设计的基础就是可靠性,因此,对无线传感器网络可靠性研究已经成为全世界在这个领域中研究的一个重点内容。无线传感器网络可靠性研究的一个有效方法就是建立数学模型。为了能够更好地进行无线传感器网络可靠性的建模,本文先介绍了无线传感器网络结构和节点模型,然后主要对无线传感器网络可靠性建模方法进行分析,提出了K-可靠性模型,并对无线传感器网络系统设计时参考依据进行简单说明。经过实践证明,无线传感器网络的可靠性完全能够通过K-可靠性模型进行测量。     

Bounding algorithms for two-terminal network reliability

Determining the exact reliability of a complex network involves extremely large amount of computation. Consequently, it is appropriate to discuss method for approximating network reliability. This paper develops methods for obtaining upper and lower bounds for two-terminal network reliability. Construction of different layers for a network is used to develop an algorithm to compute an upper bound for the reliability of a network. The nodes of this network are completely reliable and arcs fail statistically independently with known probabilities. A simple approach, to obtain a lower bound for the reliability of the network is also presented. Examples illustrate the use of the algorithms and show that the proposed bounds fare better than the well-known Esary and Proschan bounds.     

现代电力通信网可靠性研究

电力通信网可靠性在电力系统安全稳定运行中起着至关重要的作用。通过从网络自身和网络运行2个方面对电力通信网可靠性影响因素、评价指标等内容做了分析,归纳出了可靠度、平均故障间隔时间、平均修复时间和生存性4个可靠性参数并分别给出了计算公式。最后,探讨了电力通信网的可靠性研究方法,为今后电力通信网的发展研究奠定了一定的基础。     

Fuzzy logic based network reliability evaluation

A method for evaluation of the reliability of a network and its nodes is suggested reflecting the customers' requirements and needs stated in linguistic form. The method uses the fuzzy logic to formulate criteria for reliability evaluation and grading on a percentage scale. An illustrative example is included.     

Software reliability of programs with network structure

The aim of this paper is to present the reliability expression of programs/packages with general network structure, which is not sequential, branch or parallel in logic flow of the concerned algorithm. The reliability expression for logic flow (R_L) of an example program of a general network structure (whose segments are listed in Appendix 1) is discussed and thereby overall reliability expression for the entire program which can be built in several different ways is derived. Such evaluations help increase the probability of programs having complex structure to be executed without errors on the computer system. The problem is obviously of great interest to programmers/system analysts while designing the flow system, debugging or testing the program.     

空间通信中的网络可靠性分析

为研究空间通信网络的可靠性,首先介绍了空间通信环境特点及通信网络的可靠性理论基础,然后讨论了通信网络的可靠性评价指标,包括抗毁性、生存性、有效性及其计算方法。由于网络可靠性评估涉及的因素较多且相互影响,采用建立网络可靠性模型方法以研究网络部件失效及修复的情况,应用概率分析方法得到系统可靠性的数学模型,并给出了系统可靠性与节点和链路可靠性的关系,可供空间网设计参考。     

电信通信网可靠性的安全维护应用

随着我国经济的不断发展,我国电信行业发展的也越来越快.其中光纤通信技术在电信行业中也发挥着越来越重要的作用.由于光纤通信技术拥有传输快、容量大等优点,极大地满足了人们的日常通讯需求,所以人们对其的使用越来越普遍.本文详细介绍了电信光纤技术的主要功能,并结合真实的使用情况,对电信光纤未来的发展方向进行了说明,使我们能够深入了解电信光纤技术的发展.     

A new algorithm for network system reliability

In this paper, a new algorithm for reliability quantitative analysis of a network system is presented. It is well known that enumeration of the set of minimal paths for a specified node pair in network is much simpler than enumerating the set of minimal cut-sets. We have also presented a concept-half dual network, which converts the problem enumerating the cut-sets into one of enumeration of the path-sets. With the help of SHARP operation [8] we develop a recursive algorithm for calculating the reliability of a network system, which transforms the network into some subnetworks step by step, which are more simple than the former one. Finally we give a method of approximate calculating.