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Synchronization and linearity: an algebra for discrete event systems
, 2001
"... The first edition of this book was published in 1992 by Wiley (ISBN 0 471 93609 X). Since this book is now out of print, and to answer the request of several colleagues, the authors have decided to make it available freely on the Web, while retaining the copyright, for the benefit of the scientific ..."
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Cited by 363 (11 self)
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The first edition of this book was published in 1992 by Wiley (ISBN 0 471 93609 X). Since this book is now out of print, and to answer the request of several colleagues, the authors have decided to make it available freely on the Web, while retaining the copyright, for the benefit of the scientific community. Copyright Statement This electronic document is in PDF format. One needs Acrobat Reader (available freely for most platforms from the Adobe web site) to benefit from the full interactive machinery: using the package hyperref by Sebastian Rahtz, the table of contents and all LATEX crossreferences are automatically converted into clickable hyperlinks, bookmarks are generated automatically, etc.. So, do not hesitate to click on references to equation or section numbers, on items of thetableofcontents and of the index, etc.. One may freely use and print this document for one’s own purpose or even distribute it freely, but not commercially, provided it is distributed in its entirety and without modifications, including this preface and copyright statement. Any use of thecontents should be acknowledged according to the standard scientific practice. The
Hybrid Petri nets
 European Control Conference Grenoble
, 1991
"... Abstract. Petri nets (PNs) are widely used to model discrete event dynamic systems (computer systems, manufacturing systems, communication systems, etc). Continuous Petri nets (in which the markings are real numbers and the transition firings are continuous) were defined more recently; such a PN ma ..."
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Cited by 125 (0 self)
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Abstract. Petri nets (PNs) are widely used to model discrete event dynamic systems (computer systems, manufacturing systems, communication systems, etc). Continuous Petri nets (in which the markings are real numbers and the transition firings are continuous) were defined more recently; such a PN may model a continuous system or approximate a discrete system. A hybrid Petri net can be obtained if one part is discrete and another part is continuous. This paper is basically a survey of the work of the authors ’ team on hybrid PNs (definition, properties, modeling). In addition, it contains new material such as the definition of extended hybrid PNs and several applications, explanations and comments about the timings in Petri nets, more on the conflict resolution in hybrid PNs, and connection between hybrid PNs and hybrid automata. The paper is illustrated by many examples.
Discreteevent simulation of Fluid Stochastic Petri Nets
 IEEE Transactions on Software Engineering
, 1999
"... The purpose of this paper is to describe a method for simulation of recently introduced fluid stochastic Petri nets. Since such nets result in rather complex set of partial differential equations, numerical solution becomes a formidable task. Because of a mixed, discrete and continuous state space, ..."
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Cited by 36 (6 self)
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The purpose of this paper is to describe a method for simulation of recently introduced fluid stochastic Petri nets. Since such nets result in rather complex set of partial differential equations, numerical solution becomes a formidable task. Because of a mixed, discrete and continuous state space, simulative solution also poses some interesting challenges, which are addressed in the paper. 1
On reachability in autonomous continuous Petri net systems
 24 th International Conference on Application and Theory of Petri Nets (ICATPN 2003). Volume 2679 of Lecture
, 2003
"... Abstract. Fluidification is a common relaxation technique used to deal in a more friendly way with large discrete event dynamic systems. In Petri nets, fluidification leads to continuous Petri nets systems in which the firing amounts are not restricted to be integers. For these systems reachability ..."
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Cited by 13 (3 self)
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Abstract. Fluidification is a common relaxation technique used to deal in a more friendly way with large discrete event dynamic systems. In Petri nets, fluidification leads to continuous Petri nets systems in which the firing amounts are not restricted to be integers. For these systems reachability can be interpreted in several ways. The concepts of reachability and limreachability were considered in [7]. They stand for those markings that can be reached with a finite and an infinite firing sequence respectively. This paper introduces a third concept, the δreachability. A marking is δreachable if the system can get arbitrarily close to it with a finite firing sequence. A full characterization, mainly based on the state equation, is provided for all three concepts for general nets. Under the condition that every transition is fireable at least once, it holds that the state equation does not have spurious solutions if δreachability is considered. Furthermore, the differences among the three concepts are in the border points of the spaces they define. For mutual limreachability and δreachability among markings, i.e., reversibility, a necessary and sufficient condition is provided in terms of liveness. 1
Automatic Compilation of Concurrent Hybrid Factories from Product Assembly Specifications
 In Hybrid Systems: Computation and Control Workshop, Third International Workshop
, 2000
"... . We address the problem of designing a distributed, hybrid factory given a description of an assembly process and a palette of controllers for basic assembly operations. In particular, we present a method that, starting with a product assembly graph (PAG), allows us to "compile " a fa ..."
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Cited by 9 (6 self)
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. We address the problem of designing a distributed, hybrid factory given a description of an assembly process and a palette of controllers for basic assembly operations. In particular, we present a method that, starting with a product assembly graph (PAG), allows us to "compile " a factory description, consisting of a geometry and a hybrid, dynamical system representing the motions of robots on that geometry. This method is based on a formalism, which we have described in previous work, that allows us to manage the details of low level, continuous control of robot actuation and high level, logical control of various couplings of robot behaviors. The factory description is intended to be an aid in the design of an actual factory, if not directly implementable itself. 1 Introduction Large distributed networks of robots and computers form the basis of modern manufacturing systems. These systems should be rapidly reconfigurable, to adjust to design changes in the products they...
Continuization of Timed Petri Nets: From Performance Evaluation to Observation and Control
 In Proc. of the 26th Int. Conf. On Application and Theory of Petri Nets and Other Models of Concurrency
, 2005
"... Abstract. State explosion is a fundamental problem in the analysis and synthesis of discrete event systems. Continuous Petri nets can be seen as a relaxation of discrete models allowing more efficient (in some cases polynomial time) analysis and synthesis algorithms. Nevertheless computational costs ..."
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Cited by 6 (2 self)
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Abstract. State explosion is a fundamental problem in the analysis and synthesis of discrete event systems. Continuous Petri nets can be seen as a relaxation of discrete models allowing more efficient (in some cases polynomial time) analysis and synthesis algorithms. Nevertheless computational costs can be reduced at the expense of the analyzability of some properties. Even more, some net systems do not allow any kind of continuization. The present work first considers these aspects and some of the alternative formalisms usable for continuous relaxations of discrete systems. Particular emphasis is done later on the presentation of some results concerning performance evaluation, parametric design and marking (i.e., state) observation and control. Even if a significant amount of results are available today for continuous net systems, many essential issues are still not solved. A list of some of these are given in the introduction as an invitation to work on them. 1
A Case for PoManifolds in Chase After a Good Topological Model for Concurrency
, 2002
"... It has repeatedly been argued that the semicubical complexes , which derive directly from the higherdimensional automata, are as general a model for concurrency as one may ever need. In fact, most (but not all) classical examples of interacting concurrent processes have an adequate semicubical ..."
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Cited by 3 (0 self)
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It has repeatedly been argued that the semicubical complexes , which derive directly from the higherdimensional automata, are as general a model for concurrency as one may ever need. In fact, most (but not all) classical examples of interacting concurrent processes have an adequate semicubical description. I believe this is only due to the fact that most classical examples are built around the notion of discrete event, or action, which makes the transition from the example's idea to higherdimensional automata, to semicubical complexes, very natural. But it is not dicult to provide realistic examples of concurrency not based on such discrete events, which leads to local pospaces with no \cubi cation". Although the concept of local pospace is very general and admits many pathologies, the examples of concurrency I have in mind are wellbehaved and not a pathology at all, so the generality of the local pospaces is for them a large overkill. Still, they do not t into the semicubical strait jacket. This report puts forward the notion of pomanifold, a subcategory of the local pospaces slightly bigger than the semicubical complexes. A pomanifold is locally homeomorphic to a block, which is an extremely nice global pospace. The local homeomorphisms satisfy a simple consistency condition. This means the pomanifolds are \locally nice" even though they may be too smooth to admit a cubi cation.
Modeling and simulation of a hybrid system through Pr/Tr PNDAE model
 In Proceeding of ADPM98, 131137
, 1998
"... Abstract This paper deals with the modeling and simulation of a gas storage unit. The model is based on a combination of Petri nets and differential algebraic equations. The interaction between the Pr/Tr Petri nets and the equations is formally defined by means of enabling and junction functions wh ..."
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Cited by 3 (0 self)
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Abstract This paper deals with the modeling and simulation of a gas storage unit. The model is based on a combination of Petri nets and differential algebraic equations. The interaction between the Pr/Tr Petri nets and the equations is formally defined by means of enabling and junction functions which are attached to the Pr/Tr Petri net transitions. After introducing the modeling technique and illustrating it on the gas storage unit, a simulation algorithm is described.
Generalized Automata and their Net Representations
, 2001
"... We consider two generalizations of the duality between transition systems and Petri nets. In the first, transitions are replaced by paths, that is partial functions from a fixed set \Delta to states. This allows to model continuous and/or hybrid systems when \Delta represents durations. ..."
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Cited by 2 (1 self)
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We consider two generalizations of the duality between transition systems and Petri nets. In the first, transitions are replaced by paths, that is partial functions from a fixed set \Delta to states. This allows to model continuous and/or hybrid systems when \Delta represents durations.
Design Of Embedded Control Systems Using Hybrid Petri Nets
 Wegrzyn (Eds.): “Design of Embedded Control Systems”,. ISBN 0387236309
, 2001
"... . The paper describes the challenges of modeling embedded hybrid control systems at a higher abstraction level. It discusses the problems of modeling such systems and suggests the use of hybrid Petri nets. Modeling an exemplary embedded control system with a special hybrid Petri net class using an o ..."
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. The paper describes the challenges of modeling embedded hybrid control systems at a higher abstraction level. It discusses the problems of modeling such systems and suggests the use of hybrid Petri nets. Modeling an exemplary embedded control system with a special hybrid Petri net class using an objectoriented modeling and simulation tool shows the potential of hybrid Petri nets. Key Words. Embedded Control Systems, Hybrid Petri Nets 1.