基于HCPN的复杂BPMN协作模型数据流建模与验证

为了保证复杂BPMN协作模型的正确性,不仅要涵盖多实例和子进程等复杂元素,还要在检测控制流错误的同时检测数据流错误。但业务流程建模标注(BPMN 2.0)缺乏形式化语义的描述,这对模型正确性的验证造成了阻碍。因此,给出了一种具有弧权重的层次化着色Petri网(HCPN)的定义,它既可以对数据流进行形式化表示,又可以对多实例和子进程结构进行建模。进一步提出了从BPMN协作模型到HCPN模型的形式化映射方法。然后基于HCPN模型的弧权重给出了缺失、丢失和冗余3种数据流错误的定义,并提出了对应的检测算法。最后,设计了一个自动化建模与验证的框架,通过一个案例研究说明了该方法的有效性。

基于FCPN的离散制造系统质量风险分析评估研究

针对离散制造系统随机性、多样性以及复杂性的特点,高效、准确地识别系统质量风险因素并进行质量风险量化评估是制定相应质量控制活动、提高产品质量的关键。为此,首先构建模糊着色Petri网的产品质量风险评估模型。然后,确定模糊推理规则,并通过现场获取的置信度经验值进行模糊推理,计算得出中间库所和终止库所的置信度。最后,以汽车顶盖冲压工艺过程为例进行分析,验证了该模型的合理性,并且可推广应用到其他同类离散制造过程。

基于Colored Petri 网的工作流建模及应用

对传统Petri网在描述工作流模型时,组成模型的元素数量过多、无法体现数据流以及无法管理多个工作流实例等缺陷,将有色Petri网(Colored Petri net,CPN)理论的分析方法引入到工作流网(Workflow-net,WF-net),实现二者有机结合,提出了一种新型扩展工作流网CPWF-net(Workflow-net based on Colored Petri net),给出了严格的定义、使能机制和触发机制,全面分析了CPWF-net的特性,并就其实际应用进行了初步探究。

一种基于赋时Colored Petri网的工作流模型

工作流管理技术是 2 0世纪 90年代初新兴起的软件技术 ,其实现的关键在于工作流概念模型的建立。论文选择赋时ColoredPetri网 (TimedColoredPetriNet)作为工作流建模的主要工具 ,为了实现用Petri网来建立工作流模型 ,对 petri网做了适当的扩展以适应模型管理。最后通过 1个案例进一步阐述了基于Petri网的工作流建模技术。

Modeling Method of Automotive Body CAN/LIN Nets Application Protocol Based on Object-oriented Colored Petri Net

Recently automotive nets are adopted to solve increasing problems in automotive electronic systems.Technologies of automotive local area network from CAN and LIN can solve the problems of the increasing of wire bunch weight and lack in module installation space.However,the multilayer automotive nets software becomes more and more complex,and the development expense is difficult to predict and to keep in check.In this paper,the modeling method of hierarchical automotive nets and the substitution operation based on object-oriented colored Petri net(OOCPN) are proposed.The OOCPN model which analyzes the software structure and validates the collision mechanism of CAN/LIN bus can speed the automobile system development.First,the subsystems are divided and modeled by object-oriented Petri net(OOPN).According to the sets of message sharing relations,the message ports among them are set and the communication gate transitions are defined.Second,the OOPN model is substituted step by step until the inner objects in the automotive body control modules(BCM) are indivisible and colored by colored Petri net(CPN).And the color subsets mark the node messages for the collision mechanism.Third,the OOCPN model of the automotive body CAN/LIN nets is assembled,which keeps the message sets and the system can be expanded.The proposed model is used to analyze features of information sharing among the objects,and it is also used to describe each subsystem real-time behavior of processing messages and implemental device controllers operating,and puts forward a reasonable software framework for the automotive body control subsystem.The research can help to design the communication model in the automotive body system effectively and provide a convenient and rapid way for developing the logical hierarchy software.

MODELING RADIO RESOURCE MANAGEMENT IN COGNITIVE RADIO SYSTEM BASED ON OFDMA USING COLORED PETRI NET

Cognitive Radio(CR) system based on Orthogonal Frequency Division Multiple Access(OFDMA),such as Wireless Regional Area Networks(WRAN) and Worldwide Interoperability for Microwave Access(WiMAX),often attempt to improve performance via dynamic radio resource management,which is characterized as concurrent processing of different traffic and nondeterministic system capacity.It is essential to design and evaluate such complex system using proper modeling and analysis tools.In the previous work,most of the communication systems were modeled as Markov Chain(MC) and Stochastic Petri Nets(SPN),which have the explicit limitation in evaluating adaptive OFDMA CR system with wide area traffic.In this paper,we develop an executable top-down hier-archical Colored Petri Net(CPN) model for adaptive OFDMA CR system,and analyze its performance using CPN tools.The results demonstrate that the CPN can model different radio resource manage-ment algorithms in CR Systems,and the CPN tools require less computational effort than Markov model using Matlab,with its flexibility and adaptability to the traffics which arrival interval and processing time are not exponentially distributed.

A colored Petri net-based model for web service composition

In this paper, a model based colored Petri net （CPN） to provide semantic support for web service composition is proposed, and the reliability and maintainability of composite services are improved. The composite constructs in the model are sequence, concurrent, choice, loop and replace. The web service is formally defined by a CPN. A closed composing algebra is defined to obtain a framework which enables declarative composition of web services. Availability, confidentiality, and integrity of composite service are analyzed within the framework of the model based CPN.

A Parametric Colored Petri Net Model of a Switched Network

A parametric Colored Petri net model of the switched Ethernet network with the tree-like topology is developed. The model’s structure is the same for any given network and contains fixed number of nodes. The tree-like topology of a definite network is given as the marking of dedicated places. The model represents a network containing workstations, servers, switches, and provides the evaluation of the network response time. Besides topology, the parameters of the model are performances of hardware and software used within the network. Performance evaluation for the network of the railway dispatcher center is implemented. Topics of the steady-stable condition and the optimal choice of hardware are discussed.

MODELING MULTI-TRAFFIC ADMISSION CONTROL IN OFDMA SYSTEM USING COLORED PETRI NET

Call Admission Control (CAC) is one of the key traffic management mechanisms that must be deployed in order to meet the strict requirements for dependability imposed on the services provided by modern wireless networks. In this paper, we develop an executable top-down hierarchical Colored Petri Net (CPN) model for multi-traffic CAC in Orthogonal Frequency Division Multiple Access (OFDMA) system. By theoretic analysis and CPN simulation, it is demonstrated that the CPN model is isomorphic to Markov Chain (MC) assuming that each data stream follows Poisson distribution and the corresponding arrival time interval is an exponential random variable, and it breaks through MC's explicit limitation, which includes MC's memoryless property and proneness to state space explosion in evaluating CAC process. Moreover, we present four CAC schemes based on CPN model taking into account call-level and packet-level Quality of Service (QoS). The simulation results show that CPN offers significant advantages over MC in modeling CAC strategies and evaluating their performance with less computational complexity in addition to its flexibility and adaptability to different scenarios.

Using Stochastic Colored Petri nets for Designing Multi-Purpose Plants

Designing of a multi-purpose plant as one of the well-known manufacturing systems is more challenging than other manufacturing systems. This paper applies a stochastic colored Petri net (CPN) to design and analyze multi-purpose plants. A simple approach is proposed to determine the utilization of shared resources and to reduce the equipment’s idle times. Three scenarios are presented to describe the proposed model. Generally, according to desire of a decision maker, different scenarios can be considered in the model to achieve to the expected design or plant configuration. The main characteristics of the proposed model are flexibility, the easiness of practical application and the simulation of the model in an easy way.

PBB Efficiency Evaluation via Colored Petri Net Models

Basic components of Provider Backbone Bridge (PBB) network models were constructed: PBB interior switch, PBB edge switch—with the dynamic filling up of address tables. The modeling of PBB networks was implemented. The results of simulation reveal definite imperfections of PBB technology caused by the broad-casting and sensitivity to the ageing time of the address tables’ records, which complicates the guaranteeing of a given QoS. The preliminary comparison confirms definite advantages of E6 addressing before PBB.

基于GSCPN的硬件木马攻击建模与安全性分析

针对硬件木马(hardware trojan,HT)的研究主要集中在HT设计和防御的具体策略,缺乏面向HT攻击的系统安全性量化评估模型的问题,提出了基于广义随机着色petri网(generalized stochastic coloring petri net,GSCPN)的HT攻击和安全评估模型。基于单个基本单元的HT攻击行为和状态之间的时序关系,构建了单个基本单元的HT攻击GSCPN模型,根据系统工作状态下基本单元的通信依赖关系,给出了构建系统HT攻击GSCPN模型的通用方法。求解了与GSCPN模型同构的马尔可夫链的解析解,以及采用蒙特卡罗模拟方法的仿真解,二者的误差仅为0.00183,验证了所提方法建模的准确性。通过案例分析了不同场景下系统的安全性,实验结果表明,木马攻击强度、木马恢复时间和任务执行时间均对安全性有不同程度的影响。

基于CPN的车载网络无证书匿名认证和密钥协商方案研究

为了解决现有车载网络的认证方案中普遍存在密钥托管带来的缺陷,以及没有考虑计算受限电子控制单元(ECU)轻量级部署和安全快速认证的问题,首先,针对计算不受限的ECU网络,提出了一种无双线性配对的轻量级无证书匿名认证和密钥协商方案,该方案通过椭圆曲线密码体制安全构建认证密钥对,通过哈希函数和异或等轻量级方法实现匿名认证和密钥协商。然后,针对计算受限的ECU网络,提出了一种无证书批量验证方案来降低认证成本。最后,提出了一种基于有色Petri网(CPN)和Dolev-Yao攻击者模型的安全验证方法,对整体方案进行形式化安全性评估。安全评估和性能分析表明,所提方案能有效抵抗重放、伪装、篡改、已知密钥、已知特定会话临时信息攻击等多种不同类型的攻击,在保证多重安全属性的同时有较小的计算与通信成本。

基于CPN的敏捷开发业务流程建模方法

着色petri网(Colored Petri Net,CPN)建模面对大型系统时的复杂性可能会随着系统规模的增大而显著增加,通常需要较多的时间和资源。敏捷开发的方法可以通过迭代和增量的方式,将大型系统分解为多个小模块,从简化模型出发逐步增加复杂性,降低模型的复杂性,提高建模和开发的效率和质量。将CPN建模与敏捷开发相结合,可以提供更强大的建模能力和更高效的开发过程。本文以旅游出行租车系统为例,采用CPN的敏捷开发方法建立模型,并对其进行讨论和改进,为需求管理建模提供了一种具有灵活性、并发性、可视化、协作性和适应性等优势的思路。

USING COLORED-TIMED PETRI NET FOR THE SOLUTION OF DEADLOCK IN A FLEXIBLE ASSEMBLY SYSTEM

A colored timed Petri net(CTPN)modeling technique is developed for flexible assembly system(FAS) In particular,one section is devoted to the deadlock nodel based on the Petri net The rule of the deadlock error recovery is given Through the analysis of the behavioral properties of the FAS with the deadlock recovery model,the deadlock problem would be solved in the system.

Hierarchical Colored Timed Petri Nets for Maintenance Process Modeling of Civil Aircraft

Civil aircraft maintenance process simulation model is an effective method for analyzing the maintainability of a civil aircraft. First, we present the Hierarchical Colored Timed Petri Nets for maintenance process modeling of civil aircraft. Then, we expound a general method of civil aircraft maintenance activities, determine the maintenance level for decomposition, and propose the methods of describing logic of relations between the maintenance activities based on Petri Net. Finally, a time Colored Petri multi-level network modeling and simulation procedures and steps are given with the maintenance example of the landing gear burst tire of a certain type of aircraft. The feasibility of the method is proved by the example.

Web Service Automatic Composition Model Based on Colored Petri Nets

As the capability of an individual Web service is limited, it’s necessary to create new functionalities with existing Web services. Web services composition is the ability to create a new value-added service by incorporating some existing web services together. A model based colored Petri net (CPN) to provide semantic support for web service composition is proposed. The basic composite constructs in the model are sequence, concurrent, choice and loop. A closed composing algebra is defined to obtain a framework which enables declarative composition of web services. Finally modeling composite processes of Web services based on CPN is applied to a case of naval vessel command and control system.

带有时间戳的着色逻辑Petri网

针对扩展着色逻辑Petri网存在的表达能力弱以及适用范围窄的问题,提出了一个新的Petri网模型,即带有时间戳的着色逻辑Petri网。首先,将颜色进行实例化以及将变量用于构建有向边上的表达式使得模型能够传递复杂的数据流。其次,引入全局时间以及令牌的时间戳等概念为变迁使能规则增加时间上的约束,使得模型能够用于模拟实时系统。再次,定义库所约束函数并为变迁使能规则增加输出库所上的约束,使得模型能够适用于存储资源有限的场景。接着,提出基于逻辑变迁输入输出矩阵的匹配法,降低逻辑输入变迁的使能判定计算开销并简化逻辑输出变迁的使能判定计算过程。然后,重新定义适用于三类变迁的使能判定条件以及适用于三类库所的标记更新方法,解决原有模型语义在新模型中不适用的问题。最后,通过实例说明新的Petri网模型具有更强的表达能力和适用范围,它能够适用于传递复杂数据流、存储资源有限、实时的且包含批处理选择结构的系统。

Modeling and Simulation of Textile Supply Chain through Colored Petri Nets

The purpose of this paper is to describe the business process modeling and simulation of a textile supply chain using Colored Petri nets. Our model takes into account both the source process and delivery logistics that exist between any two members of supply chain;moreover, we model other activities performed by the company such as manufacturing clothing. The model has been built to acquire a better understanding about the behavior of a textile company in the fulfillment of requests from costumers. The model has been built using CPN Tools. This model was built with modules for activities of the supply chain textile, e.g. receiving orders of customers, determination of production plan, procurement raw material, transportation of raw material, production and delivering products to customers. This modularized model offers some advantages to represent complex supply chains according to their structure and requirements. Thus, we can add modules easily depending on the necessary activities.

Interrelation of Languages of Colored Petri Nets and Some Traditional Languages

The article studies the interrelation of Languages of Colored Petri Nets and Traditional formal languages. The author constructed the graph of Colored Petri Net, which generates L* Context-free language. This language may not be modeled using standard Petri Nets [1]. The Venn graph and diagram that the author modified [1], show the interrelation between languages of Colored Petri Nets and some Traditional languages. Thus the class of languages of Colored Petri Nets is supposed to include an entire class of Context-free languages.