Process architecture

About: Process architecture is a research topic. Over the lifetime, 4876 publications have been published within this topic receiving 104171 citations.

An augmented Petri Net approach for error recovery in manufacturing systems control

Abstract: The construction of error recovery Petri subnets and similar representations have received considerable attention in the literature. Previous work has presented a multi-agent system representing various levels of control in a reconfigurable architecture. Agents pertaining to production, mediation, and error recovery within such an architecture were considered. Our focus here is on the workstation level of a hierarchy where the workstation has the capability for recovery from physical errors. The implications of error recovery tasks from the perspective of control are also discussed. The approach is based on integrating Petri subnet models within a general Petri Net model for a manufacturing system environment. In essence, the error recovery plan consists of a trajectory (Petri subnet) having the detailed recovery steps that are then incorporated into the workstation control logic. The logic is based on a Timed Petri Net model of the total production system. The Petri subset models consist of a sequence of steps required to reinstate the system back to a normal state. Once generated, the recovery subnet is incorporated into the Petri Net model of the original expected (error-free) model. Petri Net augmentations pertaining to various issues are discussed in detail throughout the paper. Issues include the implication of generated error recovery trajectories in the production activities, linking of production activity Net and the error recovery subnet, potential deadlocks, the role of resources, and part handling.

Solving coverability problems of petri nets by partial deduction

Abstract: In recent work it has been shown that infinite state model checking can be performed by a combination of partial deduction of logic programs and abstract interpretation. This paper focuses on one particular class of problem--coverability for (infinite state) Petri nets--and shows how existing techniques and tools for declarative programs can be successfully applied. In particular, we show that a restricted form of partial deduction is already powerful enough to decide all coverability properties of Petri Nets. We also prove that two particular instances of partial deduction exactly compute the Karp-Miller tree as well as Finkel's minimal coverability set. We thus establish an interesting link between algorithms for Petri nets and logic program specialisation.

Supervisory Control of Petri Nets with Language Specifications

Abstract: In this chapter we discuss how Petri nets can be used in the framework of supervisory control theory. A discrete event system is defined in such a theory as a language generator: this motivates the need to start the chapter with a short but self-contained introduction to Petri net languages. We consider the monolithic supervisory design that requires to construct the concurrent composition of the plant with the specification, to check this structure for controllability and nonblockingness, and eventually to refine it. We show how Petri nets can be used within this approach and show that while the procedure can always be applied to bounded nets, in the case of unbounded Petri nets it may not be possible to obtain a Petri net supervisor.

An integrated software development methodology based on hierarchical colored Petri Nets

Abstract: This paper presents a new integrated software development methodology that uses SADT diagrams, Hierarchical CP-nets, Standard ML, and automatic mechanisms for translating SADT diagrams into Hierarchical CP-nets and for converting Hierarchical CP-nets into Standard ML executable code. A case study describes the development of a software application called the Debt Manager's Assistant, which implements a non-FIFO strategy for electronic funds transfer. This application was built for the Marine Midland Bank of New York and Societe Generale. During application development, the requirements analysis and system specification were done with the aid of the Structured Analysis and Design Technique. The system design and verification used Hierarchical Colored Petri Nets and the implementation was supported with the automatic production of executable Standard Meta Language code.