借助Petri网进行流程审计

信息的使用者往往关注保存在介质上的信息而忽视处理信息的程序。由于保存在介质上的信息有多个操作入口,即使处理信息的程序真实地反映了组织的业务流程,也难保证信息使用者所获得的信息是正确的,也就是说对于访问数据的程序,存在外部干扰。引入数据库中的审计表功能,协助信息系统审计人员识别信息系统中数据的形成是否遵循了既定的业务流程。由于Petri网是描述流程的有力工具,对于复杂的业务流程,引入Petri网对流程进行审计是必要的。     

A generalized fuzzy Petri net model

The paper proposes a new model of Petri nets based on the use of logic based neurons. In contrast to the existing generalizations, this approach is aimed at neural-type modeling of the entire concept with a full exploitation of the learning capabilities of the processing units being used there. The places and transitions of the net are represented by OR and AND-type and DOMINANCE neurons, respectively. A correspondence between this model and the previous two-valued counterpart is also revealed. The learning aspects associated with the nets are investigated     

Canonical prefixes of Petri net unfoldings

In this paper, we develop a general technique for truncating Petri net unfoldings, parameterized according to the level of information about the original unfolding one wants to preserve. Moreover, we propose a new notion of completeness of a truncated unfolding. A key aspect of our approach is an algorithm-independent notion of cut-off events, used to truncate a Petri net unfolding. Such a notion is based on a cutting context and results in the unique canonical prefix of the unfolding. Canonical prefixes are complete in the new, stronger sense, and we provide necessary and sufficient conditions for its finiteness, as well as upper bounds on its size in certain cases. A surprising result is that after suitable generalization, the standard unfolding algorithm presented in [8], and the parallel unfolding algorithm proposed in [12], despite being non-deterministic, generate the canonical prefix. This gives an alternative correctness proof for the former algorithm, and a new (much simpler) proof for the latter one.Received: 29 April 2003, Published online: 2 September 2003     

微分Petri网的稳定性分析

针对混合系统的特点,建立其微分Petri网（DPN）的模型．首先,给出一类DPN的稳定性概念和稳定性引理;然后通过引入两类函数,利用关联矩阵的信息对DPN的稳定性进行具体分析,进而构造新的复合能量函数,得到DPN的稳定性定理;最后通过仿真例子说明定理的有效性．     

面向对象Petri网建模技术综述

阐述了面向对象技术和Petri网的结合方式,提出了面向对象Petri网的建模过程,给出其详细的建模步骤和流程图,讨论了面向对象Petri网的动态特性分析方法,分析和总结了OOPN,OOCPN、OOAPN以及OOTPN的研究现状和各自建模的利弊,最后对面向对象Petri网的相关技术和发展趋势进行了综述与展望.     

基于Petri网的哲学思考

近年来,Petri网以其优秀的描述异步并发的能力以及简单、清晰的图形表示方法获得了长足的发展.同时,Petri网技术和其它技术的完美结合使其在应用领域如鱼得水.哲学高度深刻分析了Petri网之所以获得成功的思想渊源,通过诠释Petri网思想与哲学思想的诸多相通之处,帮助大家以一种全新的视角重新认识和理解Petri网.     

The Petri Net Kernel An infrastructure for building Petri net tools

The Petri Net Kernel is an infrastructure for building Petri net tools. It relieves the programmer of a Petri net tool from implementing standard operations on Petri nets and a graphical user interface. In this paper, we discuss the motivation, the concepts, and the implementation of the Petri Net Kernel. Published online: 25 July 2001     

A comparison of two Petri net types

In this article we pick up a problem stated in [1], namely the question whether PNlog-nets allow to solve synchronization problems not solvable by ordinary Petri nets under certain simulation rules. We show that a slight and reasonable strengthening of the simulation rules defined in [1] enables us to answer the raised question in the positive. As will be pointed out in the introduction, with this result we “partially” solve the original problem.     

密码协议验证中的Petri网方法

如何验证密码协议的安全性是一个复杂的问题,只有形式化的验证方法才能证明密码协议的绝对正确.利用Petri网给出了一种用于密码协议验证的形式化方法.在合理假设的基础上,区分合法用户与攻击者在执行协议时的前提条件,列出执行协议后的结果,在此基础上建立了攻击者的Petri网模型.最后,用这种方法对NSPK协议进行了验证,证明了最初的NSPK协议中存在一个安全问题,而改进的NSPK协议则消除了这个问题.证明了这种方法的有效性.     

基于Petri net的故障诊断理论研究

首先将故障概率的概念引入基于Petrinet的故障诊断方法中．针对Place和Transition．提出了P概率和T概率的概念;然后给出了它们的定义和计算定理;最后．在P概率和丁概率的基础上．对故障树分析（FTA）中“重要度”的概念略加调整,并将其引入所提出的故障诊断方法中．为Place和Transition定义了“重要度”．同时给出了计算方法．     

On the rationality of Petri net languages

We give a new interpretation of rationality for Petri net languages improving the result of Valk and Vidal (1977).     

基于Petri网的工作流模型的研究

介绍了一般Petri网及工作流网的基本定义,在基本的工作流网系统定义的基础上,引入面向对象技术及分层技术,提出了一种面向对象的工作流网的模型,以提高模型的可读性和重用性,实现流程的分层建模,降低建模复杂度.通过一个具体实例阐述了如何建立扩展工作流网模型,并通过简化技术和可达树分析方法,验证了模型的活性.     

Counting Petri net markings from reduction equations

International Journal on Software Tools for Technology Transfer - We propose a method to count the number of reachable markings of a Petri net without having to enumerate these first. The method...     

A Petri net model for probabilistic logic

In this article we investigate the use of Petri nets for the representation of possible worlds in probabilistic logic. We propose a method to generate possible worlds based upon the reachability tree of the Petri net model. The number of columns in the matrix of possible worlds grows exponentially with the problem size. Nilsson [Proceedings of 1976 National Computer Conference and Readings in Artificial Intelligence, Morgan Kaufmann, Los Altos, CA, 1981, pp. 192-199] suggested a method to generate only those columns of the possible world matrix that are likely to be important for the solution. We provide Petri net models for the method suggested by Nilsson and show that they lead to intuitive and simple computational methods. © 1996 John Wiley & Sons, Inc.     

基于着色Petri网的工作流模型研究

针对传统Petri网建模方法的不足,研究了通过资源结构建模的工作流建模方法.在着色Petri网的基础上提出资源/任务网(R/T-net),并给出基于R/T-net的工作流建模过程.R/T模型能够有效地实现产品数据结构和过程结构的统一,资源流对任务流的控制以及模型的仿真.     

Using Petri net graphs express boolean functions

Both the combination and sequential switching function, also called switching circuits, can be represented by the binary code with Boolean algebra and Finite State Machine （FSM）. The basic elements of Petri net graph, such as place nodes, transition nodes, arcs, and tokens are used to frame the OR, NOT, and NOR logic function. Furthermore, to illustrate AND, and NAND switching function using the foregoing switching function, which is implemented by the Petri net graph. The main purpose of the paper is to prove ours hypothesis that the most logic function can be represented by the Petri net graph. Ultimately, our assumptions are complemented trustily.     

Deterministic weak-and-marked Petri net languages are regular

The intersection of the class of deterministic weak and the class of deterministic marked Petri net languages is the class of regular languages. We prove this result using a lemma that characterizes regular deterministic Petri net languages