仿真技术在通信网可靠性研究中的应用

论文主要对用仿真技术来研究通信网的可靠性的一些基本技术作探讨，就目前通过网可靠性研究和观点和方法作简要归纳，并对运用仿真方法来求出通信网的可靠性测度之一的全网端间业务完成性作了较具体的阐述。     

基于运行统计的通信网可靠性的综合实用评价方法

本文以评价可靠必珠增长平为出发点,提出了一种简单、实用的评价方法,有助于直接了解可靠性的增减变动;并以电话网为例构建了相应的模型,给出了分析结果。     

探讨仿真技术在通信网可靠性研究中的运用

本文主要对用仿真技术来研究通信网的可靠性的一些基本技术作探讨，简要的就目前通信网可靠性研究中的观点和方法作一些归纳，并对运用仿真方法来求出通信网的可靠性测度之一的全网端间业务完成度作了较具体的阐述。     

电力通信网可靠性分析评估方法探究

电网建设及运维工作需要不断提高电力通信网的可靠性。本文分析了当前电力通信网可靠性巩固中存在的问题,并从电网安全运行支撑能力的角度,建立了一种简单实用的通信网可靠性评估模型,并介绍了线路保护业务和光传输网的可靠性评估方法,用于开展电力通信网可靠性的分析评价。     

ATM技术在计算机通信网中的应用

本简要介绍了ATM的信元、原理、协议结构，对ATM和IP技术进行简单对比，最后分别以LANE和DSLAM为例，讨论了ATM在计算机通信网中的应用。     

ATM在移动通信网中的应用

分析了在移动网中ＡＴＭ应用的相关技术及其研究现状，并对基于ＡＴＭ的移动通信网的发展过程作出预测。     

电力通信网可靠性分析评估方法探讨

对于电网而言,其对于通信网的依赖性在不断的增强,在一定程度上对于通信网的安全可靠性提出了越来越高的要求,特别是在电力通信网的规模不断加大和结构日渐复杂的现阶段,其安全生产方面也面临着巨大的挑战,要求高效开展通信网的可靠性分析评估工作.基于此,本文从电力通信网可靠性分析评估工作的现状为着手点,对其分析评估方法进行了深入的探讨.     

RS-RBFNN在电力通信网可靠性评估中的应用

指标体系的建立是通信网可靠性评估工作中的一个重要环节,然而由于指标的不确定性和指标间的复杂关系,使得指标的选取以及合理指标体系的建立都变得非常困难。为了解决指标的选取问题,文章采用粗糙集（Rs）理论中的属性约简与径向基神经网络（RBFNN）相结合的方法对电力通信网可靠性进行仿真评估。该方法通过降低径向基神经网络输入的维数来提高神经网络的训练速度和评估能力。仿真结果验证了该方法在通信网可靠性评估中的有效性与可行性。     

改进物元可拓在航班延误预警中的应用

航班延误预警是典型的多因素问题。为解决该问题,从空管的角度出发,基于容量变化、需求变化两方面选取机场通行能力下降率等6个代表性指标,构建航班延误预警指标构架。对物元可拓模型,使用变权理论确定其指标权重值,用规格化改进和非对称贴进度计算贴进度,得到改进模型。最后对我国危险天气条件下的某空域进行仿真验证,对比原有模型和改进后的模型。评价结果表明了改进后模型的有效性。     

一种随机Petri网性能等价化简与分析方法

随机Petri网模型是系统性能评价的有力工具,但其状态空间随模型规模的增长而指数性增长的问题限制了其对复杂和大规模系统模型的性能数量分析能力.因此,在对模型进行分析之前,先对其进行适当的性能等价化简,是一种更为可行的分析方法.本文首先讨论了一类随机Petri网-基本随机Petri网(ESPN)的性能等价分析方法,这类随机Petri网由顺序、并行、选择和循环等四种基本结构及其组合构成.作者推导出这四种基本结构的性能等价公式,并运用自底向上逐步综合替代的分层分析方法,给出这类随机Petri网模型的性能等价化简分析方法,该方法的复杂性随模型增长而线性增长,有效解决了其性能数量分析问题.然后,讨论了两种非基本结构到基本结构的转换规则,使得复杂的随机Petri网模型也可能转换为ESPN模型,从而使性能等价算法可应用于一般随机Petri网.     

基于随机高级Petri网的ATM网络接纳控制过程模型

本文提出了一个ＡＴＭ网络的接纳控制过程模型，此模型是基于随机高级Ｐｅｔｒｉ网的层次模型方法。在复杂的ＡＴＭ网络的接纳控制过程模型中，使用了从顶向下的模型方法。在模型的性能分析中，则采用了从底向上的分解、压缩的方法。这种方法简化了复杂系统模型的状态空间爆炸问题。     

随机高级Petri网用于计算机网络传输协议的模型与性能评价

本文讨论了具有标记变量的随机高级Ｐｅｔｒｉ网（ＳＨＬＰＮ）以及标识类型，标记变量和等价标记变量的概念，给出了具有等价标记变量可达树构造算法，并证明了等价标记变量可达集与合并状态的马尔可夫链状态空间之间的同构。本文着重描述了ＳＨＬＰＮ在计算机网络传输协议的模型与性能评价中扩，通过这个例子充分显示了这些概念和算法的有效性。     

随机Petri网模型中变迁的串、并联性能等价化简技术

随机Petri网的状态空间爆炸问题的研究始终是Petri网研究的主要问题之一.在随机Petri网模型中,变迁的串、并联是Petri网模型的主要基本形式,对它的化简不仅有助于解决随机Petri网状态空间的爆炸问题,而且也为其他随机Petri网的化简技术提供一个坚实的基础.另外在诸如工作流、多媒体等重要的随机Petri网模型中也存在大量的变迁的串、并联结构,所以对随机Petri网模型变迁的串、并联的化简,特别是能够推导出它的性能等价的数学公式就显得很有必要.本文详细阐述了随机Petri网变迁的串并联的模型化简技术,推导出了变迁的串、并联化简的性能等价公式,并给出一个化简的例子,最后对结果的相关问题进行了分析.     

随机高级Petri网在异构系统中的应用

传统的随机高级Petri网(Stochastic high-level Petri nets,SHLPNs)通过将多个同构子系统压缩成一个子系统,并将具有相同标记分布的多个标识压缩成一个标识(复合标识),从而有效地减小模型规模和状态空间.但该方法仅适用于若干同构子系统组成的系统中,本文将这种方法扩展,通过引入非对称的变迁实施谓词和扩展的复合标识,精确地模型并分析异构系统,同时也保持了SHLPNs在化简模型和状态空间方面的优越性.     

Analytical modeling of Transmission Control Protocol NewReno using Generalized Stochastic Petri Nets

This paper presents a novel analytical model of Transmission Control Protocol (TCP) using a generalized stochastic Petri net (GSPN). Extensive simulation work has been done for the performance evaluation of TCP NewReno protocol. In view of the limitations of the simulation technique, we present an analytical approach using GSPN. A GSPN is a useful mathematical tool that solves continuous time Markov chains for complex systems and evaluates the stationary behavior. In this paper, we analyze the slow‐but‐steady variant of TCP NewReno. The model captures the behavioral aspects of the slow start and the congestion avoidance phase together with the fast retransmit and recovery capabilities of TCP NewReno. Performance metrics such as throughput, goodput, and task completion time of the system are obtained. The effect of variation in the model parameters on the performance is studied. The results are validated using the network simulator, and their accuracy is verified by evaluating the confidence interval. The performance of the proposed model is compared with that of TCP Reno. The performance of the proposed model is also compared with one of the previous models. The numerical illustrations and comparison of the proposed technique with simulation validates the accuracy, efficiency, and competence of the GSPN technique. While GSPN modeling for TCP is investigated in depth for the TCP NewReno and TCP Reno variant in this paper, other protocols could be also analyzed similarly. Copyright © 2013 John Wiley & Sons, Ltd.     

Modeling Mobility Tracking Procedures in PCS Systems Using Stochastic Activity Networks

In this paper the capability of stochastic activity networks (SANs) has been used as a novel approach in the analysis of mobility tracking procedures. To evaluate complex systems such as cellular systems, powerful tools for modeling and analysis are required. SANs have proved to be very flexible and powerful tools in the study of location update (LU) and paging (PG) schemes. SANs can capture, in a simple manner and from the mobility models under study, much more detail than Markov models. Therefore, the analysis of mobility tracking procedures with SANs provides more accuracy than the use of Markov models. This fact is illustrated in the paper by considering the LU and PG schemes proposed in Ref. [12]. Furthermore, our results show a much better performance of these schemes than that predicted by Ref. [12].     

弹载1553B总线网络控制系统Petri网建模与性能分析

鉴于数据传输总线的诸多优点,未来的弹载控制系统采用总线式网络化控制方式成为一个重要的发展方向。在该类系统的设计过程中,必须对各类设计方案进行形式化建模和性能评价。以确定与随机Petri网为理论工具,建立了基于1553B总线的弹载控制系统在非周期性消息和周期性消息同时存在的复杂情况下的形式化模型,并在模型基础上推导出了相关的性能指标公式。通过对指标的分析,为弹载控制网络的设计和优化提供了理论依据。     

A Case Study for the Application of Deterministic and Stochastic Petri Nets in the SoC Communication Domain

This paper presents an approach utilizing deterministic and stochastic Petri nets (DSPN) to analyze on-chip communication. In order to demonstrate the suitability of this approach, the on-chip communication structure of two examples featuring typical system-on-chip (SoC) communication conflicts like competition for common communication resources have been studied. A state-of-the-art heterogeneous digital signal processor (DSP) and a design example with an on-chip bus have been examined. The results show that sufficient modeling accuracy can be achieved with low modeling effort in terms of computation and implementation time. Holger Blume received his Dipl.-Ing. degree in electrical engineering from the University of Dortmund, Germany in 1992. From 1993 to 1998 he worked as a research assistant with the Working group on Circuits and Systems for Information Processing of Prof. Dr. H. Schrŝder in Dortmund. There he finished his PhD on Nonlinear fault tolerant interpolation of intermediate images in 1997. In 1998 he joined the Chair of Electrical Engineering and Computer Systems of Prof. Dr. T. G. Noll at the University of Technology RWTH Aachen as a senior engineer. His main research interests are in the field of heterogeneous reconfigurable Systems on Chip for multimedia applications. Dr. Blume is chairman of the German chapter of the IEEE Solid State Circuits Society. Thorsten von Sydow received the Dipl.-Ing. degree from the University of Technology RWTH Aachen, Germany, in 2002. Since then he is working as a research assistant at the Chair of Electrical Engineering and Computer Systems (Prof. T. G. Noll), University of Technology RWTH Aachen. His current research interests include Design Space Exploration for on-Chip interconnects and fine grain arithmetic oriented eFPGA architectures. Tobias G. Noll received the Ing. (grad.) degree in Electrical Engineering from the Fachhochschule Koblenz, Germany in 1974, the Dipl-Ing. degree in Electrical Engineering from the Technical University of Munich in 1982, and the Dr.-Ing. degree from the Ruhr-University of Bochum in 1989. From 1974 to 1976, he was with the Max-Planck-Institute of Radio Astronomy, Bonn, Germany, beeing active in the development of microwave waveguide and antenna components. Since 1976 he was with the Corporate Research and Development Department of Siemens and since 1987 he headed a group of laboratories concerned with the design of algorithm specific integrated CMOS circuits for high-throughput digital signal processing. In 1992, he joined the Electrical Engineering Faculty of the University of Technology RWTH Aachen, Germany, where he is a Professor, holding the chair of Electrical Engineering and Computer Systems. In addition to teaching, he is involved in research activities on VLSI architectural strategies for high-throughput digital signal processing, circuits concepts, and design methodologies with a focus on low power CMOS and deep submicron issues, as well as on digital signal processing for medicine electronics.     

主体计划的Petri网方法及正确性验证

主体计划的生成问题是多主体系统实现的一个关键问题.为了实现多主体系统中的计划自动生成以及对生成的计划进行验证,以任务有效分解的Petri网模型为基础,提出了计划提取的方法并对相关的正确性运用同步器进行验证.首先,通过对网系统的可达性分析得到所有计划的集合,组成多主体系统的计划库.其次,根据同步网的相关思想,对计划库中的每一个计划的正确性进行了形式化的验证,从而为多主体系统的实现提供了保证.