Stéphane Julia

Real time scheduling of batch systems

Abstract The approach presented in this article is based on the real time simulation of p -time Petri net for the real time scheduling of batch systems. After defining the different kinds of constraints that can exist in a linear hybrid production system, we present the conflict resolution principle used by a token player algorithm at the global coordination level.

Real-time scheduling of batch systems using Petri nets and linear logic

This paper presents an approach to model, design and verify scenarios of real-time systems used in the scheduling and global coordination of batch systems. The initial requirements of a system specified with sequence diagrams are translated into a single p-time Petri net model representing the global behavior of the system. For the Petri net fragments involved in conflicts, symbolic production and consumption dates assigned to tokens are calculated based on the sequent calculus of linear logic. These dates are then used for off-line conflict resolution within a token player algorithm used for scenario verification of real-time specifications and which can be seen as a simulation tool for UML interaction diagrams.

Qualitative analysis of WorkFlow nets using linear logic: Soundness verification

This paper presents a method for the qualitative analysis of WorkFlow nets based on the proof trees of linear logic. The analysis is concerned with the proof of the correctness criterion soundness defined for WorkFlow nets. To prove the soundness property, a proof tree of linear logic is built for each different scenario of the WorkFlow net. Based on this approach, a method is proposed to verify in linear time if the WorkFlow net is sound.

Game modeling using WorkFlow nets

The objective of this article is to present an approach based on WorkFlow net and Linear Logic for the design process of video games. The main idea consists of representing the scenarios existing at a quest level by a particular type of Petri net called WorkFlow net. A kind of qualitative analysis based on the proof trees of linear logic can then be performed in order to prove the correctness of the soundness property which corresponds to a consistent quest from the point of view of the game. An extended version of theWorkFlow nets which allows the inclusion of discrete resources permits representing in a formal way, the different items that the player can find and use during the quests of the game.

Scheduling batch systems using a token player algorithm

The objective of this article is to show how we can use models and methods generally used in the manufacturing area to treat the scheduling problem of batch systems. The approach is based on the representation of the system constraints using a p-time t-timed Petri net model and on a token player algorithm with a backtrack mechanism to find a feasible sequence consistent with the set of constraints.

Deadlock-Freeness Scenarios Detection in Web Service Composition

This paper presents a method for deadlock-freeness scenarios detection in Web services composition. This method considers the Petri nets theory and is based on the analysis of Linear Logic proof trees. To detect the deadlock-freeness scenarios, a Linear Logic proof tree is built for each different scenario of the modules from which the composed system is built. These proof trees are analysed and some candidates to be used in deadlock-freeness scenarios are identified. These candidates are proven by the construction and analysis of a Linear Logic proof tree that considers the local scenarios involved within it. Then, the deadlock-freeness scenarios can be analysed by the organization staff to decide if these scenarios can provide all their necessary business relationships.

Qualitative Analysis of Interorganizational WorkFlow Nets Using Linear Logic: Soundness Verification

This paper presents a method for qualitative analysis of Interorganizational WorkFlow nets based on the proof trees of Linear Logic. This analysis is concerned with the proof of the Soundness correctness criterion defined for Interorganizational WorkFlow nets. To prove the Soundness property, a proof tree of Linear Logic is built for each different scenario of the IOWF-net and for the Local WorkFlow nets from which it is composed. The proposed method permits one to verify Soundness without deciding boundedness that is EXPSPACE-hard and considers the very structure of the net. Furthermore, the proposed approach gives guidance for the adjustment of interorganizational workflow processes that do not satisfy Soundness.

Linear Logic as a Tool for Deadlock-Freeness Scenarios Detection in Interorganizational Workflow Processes

This paper presents a method for deadlock-freeness scenarios detection in interorganizational workflow processes. This method considers the Interorganizational WorkFlow nets theory and is based on the analysis of Linear Logic proof trees. To detect the deadlock-freeness scenarios, a Linear Logic proof tree is built for each different scenario of the Local WorkFlow nets from which the Interorganizational WorkFlow net is composed. These proof trees are analysed and some candidates to be used in deadlock-freeness scenarios are identified. These candidates are proven by the construction and analysis of a Linear Logic proof tree that considers the local scenarios involved within it. Then, the deadlock-freeness scenarios can be analysed by the organizations staff to decide if these scenarios can provide all their necessary business relationships.

Centralized Architecture for Real Time Scheduling of Batch Systems

Abstract The objective of this article is to present a centralized architecture based on a collaboration diagram and on a p-time Petri net model for real time scheduling of production systems. The main idea consists of proposing a software architecture which depends on an object whose purpose is to centralize all the interactions between the different software objects. The internal behaviour of the central object is represented by a p-time Petri net model which shows the global behaviour of the entire system. A specialized inference mechanism called token player is then applied to the p-time Petri net model for the real time scheduling. In particular, for the Petri net fragments involved in conflict situations, symbolic dates assigned to tokens are calculated using a non-conventional (max;+) algebra based on the sequent calculus of Linear Logic. These dates are used to solve conflict situations off-line on an implicit manner in such a way that the resource conflicts can be treated in real time at the central object level. The approach is illustrated through an example of Real Time System used at the global coordination level of a Batch System.

Possibilistic WorkFlow Nets for Dealing with Cancellation Regions in Business Processes

In this paper, an approach based on WorkFlow nets and possibilistic Petri nets is proposed for dealing with the cancellation features in business processes. Routing patterns existing in business processes are modeled by WorkFlow nets. Possibilistic Petri nets with uncertainty in the marking and the transition firing are used to deal with all possible markings when cancellation behaviour is considered. Combining both formalisms, a kind of possibilisticWorkFlow net is obtained. An example of a simplified version of a credit card application process is presented.