**7. References**


Boucher, T.; Jafari, M.; Meredith, G. Petri net control of an automated manufacturing cell. Computers and Industrial Engineering, Tarry Town, NY, USA, v. 17, n.1, p.459-463, 1989.

104 Petri Nets – Manufacturing and Computer Science

Tiago Facchin and Miguel Afonso Sellitto

*Universidade do Vale do Rio do Sinos - UNISINOS, Brazil* 

concurrently competing process flows.

It was presented and tested a method based on modelling an simulation by Petri Nets and Throughput Diagram for the calculation of two important indicators in manufacturing management: in process inventory and lead time. With the simulation results (provided by the Petri Net model outputs and the throughput diagram) the manufacturing process can be predicted, as well as some modification can be measured and analyzed to optimize the production. As well as save money on alterations that could produce losses in production

AEP- Associação Empresarial de Portugal. Métodos e Tempos: Manual Pedagógico. Leça da

Antunes, J.; Alvarez, R.; Klippel, M.; Bortolotto, P.; Pellegrin, I. Sistemas de Produção. Porto

Askin, R.; Krisht, A. Optimal Operation of Manufacturing Systems with Controlled Workin-Process Levels. International Journal of Production Research, London, v.32, n.7,

Banaszak, Z.; Krogh, B. Deadlock avoidance in flexible manufacturing systems with

Bechte, W. Load-oriented manufacturing control just-in-time production for job shops.

Breithaupt, J.; Land, M.; Nyhuis, P. The workload control concept: theory and practical extensions of Load Oriented Order Release. Production Planning & Control, London,

Bitran, G.; Sarkar, D. Throughput Analysis in Manufacturing Networks. European Journal

Bitran, G.; Morabito, R. Um exame dos modelos de redes de filas abertas aplicados a sistemas de manufatura discretos: Parte I. Gestão & Produção, São Carlos, v. 2, n.2,

Bitran, G.; Morabito, R. Um exame dos modelos de redes de filas abertas aplicados a sistemas de manufatura discretos: Parte II. Gestão & Produção, São Carlos, v. 2, n.3,

Bitran, G.; Dasu, S. A review of open queueing network models of manufacturing systems.

Castrucci, P.; Moraes, C. Engenharia de automação industrial. Rio de Janeiro: LTC, 2001.

IEEE Transactions on Robotics and Automation, v.6, n.6, p.724-734, 1990.

Production Planning & Control, London, v.5, n.3, p.292-307, 1994.

of Operational Research, v.74, n.3, p.448-465, 1994.

Queuing Systems, v.12, n.1-2, p. 95-133, 1992.

processes and often, in the real world, are hard to be perceived.

**6. Final considerations** 

**Author details** 

**7. References** 

Palmeira, 2003.

p.1637-1653, 1994.

Alegre: Bookman, 2007.

v.13, n.7, p. 625-638, 2002.

p.192-219, 1995.

p.297-320, 1995A.


Reisig, W. Elements of distributed algorithms: modeling and analysis with Petri Nets. Berlim: Springer Verlag, 1998.

**Chapter 6** 

© 2012 Yuan, licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

© 2012 Yuan, licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

**Workflow Modelling Based on Synchrony** 

Prof. Carl Adam Petri wrote: "In order to apply net theory with success, a user of net theory can just rely on the fact that every net which he can specify explicitly (draw on paper) can be connected by a short (≤ 4) chain of net morphisms to the physical real word; your net is, in a very precise sense, physically implementable." (Status Report On Net Theory, 1989, a

Why a net is physically implementable? The reason is, every concept in net theory is carefully chosen based on nature laws, and well defined in terms of precise mathematics and logic. For example, the concept of global time does not belong to net theory. Time measured with real numbers exists only in theories like theoretical physics. Logical time does not exist in the real world. For net theory, time is just "clock reading", a measurement of physical changes. Global time is not realistic for systems in which a shared clock is not

On the other hand however, it is easy to find in the literature, that many an author introduces new concepts into his or her Petri net with implementation totally forgotten.

As one of the chapters in this book on Petri nets, implementable concepts and only

We start with the definition of a directed net, which is the most fundamental concept in net

Sections 2 and 3 recall basic definitions of Petri Nets: The concept of directed net deserves a separate section since it is the foundation of the whole net theory. Section 3 is mainly about

Place/Transition-systems, based on which workflow models are to be constructed.

Additional information is available at the end of the chapter

forward for my book Petri Nets in Chinese[1]).

"Timed Petri Net" is just one of such examples.

theory. The next two sections serve to keep this chapter self-reliant.

implementable concepts will be introduced.

This chapter is organized as below:

Chongyi Yuan

**1. Introduction** 

available.

http://dx.doi.org/10.5772/48375

