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This book offers a new Modular Petri Net as a solution to the vast Petri net models. It presents some approaches centering around modules (known as “Petri modules”). The goal of this book is to introduce a methodology in which Petri nets are moved to a new level. In this new level, large Petri net models are made of Petri modules, which are independent and run on different computers. This book also contains the literature study on modular Petri nets and definitions for the newer Petri modules. Also, algorithms for extracting Petri modules, and algorithms for connecting Petri modules, and applications are given in this book. Besides, the ideas and algorithms given in this book are implemented in the software General-purpose Petri Net Simulator (GPenSIM). Hence, with the use of this book the readers/users would be able to know that real-life discrete event systems could be modeled, analyzed, and performance-optimized with GPenSIM.

This book deals with the problem of finding suitable languages that can represent specific classes of Petri nets, the most studied and widely accepted model for distributed systems. Hence, the contribution of this book amounts to the alphabetization of some classes of distributed systems. The book also suggests the need for a generalization of Turing computability theory.It is important for graduate students and researchers engaged with the concurrent semantics of distributed communicating systems. The author assumes some prior knowledge of formal languages and theoretical computer science.

This book presents for the first time a methodology that combines the power of a modelling formalism such as colored petri nets with the flexibility of a discrete event program such as SIMIO. Industrial practitioners have seen the growth of simulation as a methodology for tacking problems in which variability is the common denominator. Practically all industrial systems, from manufacturing to aviation are considered stochastic systems. Different modelling techniques have been developed as well as mathematical techniques for formalizing the cause-effect relationships in industrial and complex systems. The methodology in this book illustrates how complexity in modelling can be tackled by the use of coloured petri nets, while at the same time the variability present in systems is integrated in a robust fashion. The book can be used as a concise guide for developing robust models, which are able to efficiently simulate the cause-effect relationships present in complex industrial systemswithout losing the simulation power of discrete-event simulation. In addition SIMIO's capabilities allows integration of features that are becoming more and more important for the success of projects such as animation, virtual reality, and geographical information systems (GIS).

The master thesis of Susanne Göbel generates the deep understanding of the Mobile Ambient (MA) calculus that is necessary to use it as a modeling language. Instead of calculus terms a much more convenient representation via MA trees naturally maps to the application area of networks where processes pass hierarchical protection domains like firewalls. The work analyses MA's function principles and derives a translation into Safe Petri nets. It extends to arbitrary MA processes but finiteness of the net and therefore decidability of reachability is only guaranteed for bounded processes. The construction is polynomial in process size and bounds so that reachability analysis is only PSPACE-complete.

Auf dem Gebiet der Petri-Netze und Vektoradditionssysteme sind viele Entscheidungsfragen ungeklärt, die Uli Schlachter in seiner Masterarbeit motiviert haben, Spiele auf sogenannten Spielstrukturen mit einer ähnlichen Semantik zu untersuchen. Hierbei handelt es sich um eine Art von Zwei-Spieler-Spielen auf einem gerichteten Graphen. Der Autor erarbeitet verschiedene Gewinnbedingungen und zeigt ihre Entscheidbarkeit. Die Arbeit beleuchtet diese Themen spieltheoretisch, bietet aber auch eine exemplarische Anwendung verschiedener Aspekte der Spieltheorie.

Petri nets are a formal and theoretically rich model for the modelling and analysis of systems. A subclass of Petri nets, augmented marked graphs possess a structure that is especially desirable for the modelling and analysis of systems with concurrent processes and shared resources.This monograph consists of three parts: Part I provides the conceptual background for readers who have no prior knowledge on Petri nets; Part II elaborates the theory of augmented marked graphs; finally, Part III discusses the application to system integration. The book is suitable as a first self-contained volume on augmented marked graphs, and will be useful to both researchers and practitioners in the fields of Petri nets and system integration.

This book presents a coherent description of the theoretical and practical aspects of Coloured Petri Nets (CP-nets or CPN). It shows how CP-nets have been de­ veloped - from being a promising theoretical model to being a full-fledged lan­ guage for the design, specification, simulation, validation and implementation of large software systems (and other systems in which human beings and/or com­ puters communicate by means of some more or less formal rules). The book contains the formal definition of CP-nets and the mathematical theory behind their analysis methods. However, it has been the intention to write the book in such a way that it also becomes attractive to readers who are more interested in applications than the underlying mathematics. This means that a large part of the book is written in a style which is closer to an engineering textbook (or a users'manual) than it is to a typical textbook in theoretical computer science. The book consists of three separate volumes. The first volume defines the net model (i. e., hierarchical CP-nets) and the basic concepts (e. g., the different behavioural properties such as deadlocks, fair­ ness and home markings). It gives a detailed presentation of many small exam­ ples and a brief overview of some industrial applications. It introduces the for­ mal analysis methods. Finally, it contains a description of a set of CPN tools which support the practical use of CP-nets.

With their intuitive graphical approach and expressive analysis techniques, Petri nets are suitable for a wide range of applications and teaching scenarios, and they have gained wide acceptance as a modeling technique in areas such as software design and control engineering. The core theoretical principles have been studied for many decades and there is now a comprehensive research literature that complements the extensive implementation experience.In this book the author presents a clear, thorough introduction to the essentials of Petri nets. He explains the core modeling techniques and analysis methods and he illustrates their usefulness with examples and case studies. Part I describes how to use Petri nets for modeling; all concepts are explained with the help of examples, starting with a generic, powerful model which is also intuitive and realistic. Part II covers the essential analysis methods that are specific to Petri nets, introducing techniques used to formulate keyproperties of system nets and algorithms for proving their validity. Part III presents case studies, each introducing new concepts, properties and analysis techniques required for very different modeling tasks. The author offers different paths among the chapters and sections: the elementary strand for readers who wish to study only elementary nets; the modeling strand for those who wish to study the modeling but not the analysis of systems; and finally the elementary models of the modeling strand for those interested in technically simple, but challenging examples and case studies.The author achieves an excellent balance between consistency, comprehensibility and correctness in a book of distinctive design. Among its characteristics, formal arguments are reduced to a minimum in the main text with many of the theoretical formalisms moved to an appendix, the explanations are supported throughout with fully integrated graphical illustrations, and each chapter ends with exercises and recommendations for further reading.The book is suitable for students of computer science and related subjects such as engineering, and for a broad range of researchers and practitioners.

High-level Petri nets are now widely used in both theoretical analysis and practical modelling of concurrent systems. The main reason for the success of this class of net models is that they make it possible to obtain much more succinct and manageable de­ scriptions than can be obtained by means of low-level Petri nets-while, on the other hand, they still offer a wide range of analysis methods and tools. The step from low-level nets to high-level nets can be compared to the step from assembly languages to modem programming languages with an elaborated type concept. In low-level nets there is only one kind of token and this means that the state of a place is described by an integer (and in many cases even by a boolean value). In high-level nets each token can carry complex information which, e. g., may describe the entire state of a process or a data base. Today most practical applications of Petri nets use one of the different kinds of high-level nets. A considerable body of knowledge exists about high-level Petri nets­ this includes theoretical foundations, analysis methods and many applications. Unfortunately, the papers on high-level Petri nets have been scattered throughout various journals and collections. As a result, much of this knowledge is not readily available to people who may be interested in using high-level nets.

Coloured Petri Nets (CPN) is a graphical language for modelling and validating concurrent and distributed systems, and other systems in which concurrency plays a major role. The development of such systems is particularly challenging because of inherent intricacies like possible nondeterminism and the immense number of possible execution sequences. In this textbook Jensen and Kristensen introduce the constructs of the CPN modelling language and present the related analysis methods in detail. They also provide a comprehensive road map for the practical use of CPN by showcasing selected industrial case studies that illustrate the practical use of CPN modelling and validation for design, specification, simulation, verification and implementation in various application domains. Their presentation primarily aims at readers interested in the practical use of CPN. Thus all concepts and constructs are first informally introduced through examples and then followed by formal definitions (which may be skipped). The book is ideally suitable for a one-semester course at an advanced undergraduate or graduate level, and through its strong application examples can also serve for self-study. An accompanying website offers additional material such as slides, exercises and project proposals. Book website: http://www.cs.au.dk/CPnets/cpnbook/

Petri nets do not designate a single modeling formalism. In fact, newcomers to the field confess sometimes to be a little puzzled by the diversity of formalisms that are recognized under this'umbrella'. Disregarding some extensions to the theoretical modeling capabilities, and looking at the level of abstraction of the formalisms, Condition/Event, Elementary, Place/Transition, Predicate/Transition, Colored, Object Oriented... net systems are frequently encountered in the literature. On the other side, provided with appropriate interpretative extensions, Controled Net Systems, Marking Diagrams (the Petri net generalization of State Diagrams), or the many-many variants in which time can be explicitly incorporated -Time(d), Deterministic, (Generalized) Stochastic, Fuzzy...- are defined. This represents another way to define practical formalisms that can be obtained by the'cro- product'of the two mentioned dimensions. Thus Petri nets constitute a modeling paradigm, understandable in a broad sense as'the total pattern of perceiving, conceptualising, acting, validating and valuing associated with a particular image of reality that prevails in a science or a branch of science'(Thomas S. Kuhn).

Formal methods for the specification and verification of hardware and software systems are becoming more and more important as systems increase in size and complexity. The aim of the book is to illustrate progress in formal methods, based on Petri net formalisms. It contains a collection of examples arising from different fields, such as flexible manufacturing, telecommunication and workflow management systems.The book covers the main phases in the life cycle of design and implementation of a system, i.e., specification, model checking techniques for verification, analysis of properties, code generation, and execution of models. These techniques and their tool support are discussed in detail including practical issues. Amongst others, fundamental concepts such as composition, abstraction, and reusability of models, model verification, and verification of properties are systematically introduced.