Simulation and Formal Analysis of Workflow Models

Behavioral models capture operational principles of real-world or designed systems. Formally, each behavioral model defines the state space of a system, i.e., its states and the principles of state transitions. Such a model is the basis for analysis of the system's properties. In practice, state spaces of systems are immense, which results in huge computational complexity for their analysis. Behavioral models are typically described as executable graphs, whose execution semantics encodes a state space. The structure theory of behavioral models studies the relations between the structure of a model and the properties of its state space.

Proceedings of the 2005 OOPSLA workshop on Eclipse technology eXchange - eclipse '05, 2005

Application and Theory of Petri Nets 1997, 1997

… of Concurrency to …, 2006

This paper presents Yasper, a tool for modeling, analyzing and simulating workflow systems, based on Petri nets. Yasper puts Petri net modeling in the hands of business analysts and software architecture designers. They can specify systems in familiar terms (XOR choice, workflow, cases, roles, processing time and cost), and can directly run manual and automatic simulations on the resulting models to analyze correctness and performance. Yasper was designed to cooperate with other tools, such as Petri net analyzers, and off-the-shelf software for data (color) handling and forms handling.

Appropriate definition, analysis, checking and improvement of business process models are indispensable before their deployment within workflow management systems. In this paper, we focus on business process model verification that insures business process structural correctness. Our proposal consist in a new hybrid algorithm of workflow graph structural validation combining graph reduction and traversal mechanisms. Our algorithm will be discussed and compared to existing workflow structural checking approaches. Our Algorithm has been implemented within our prototype WorklowChecker that we present through this demonstration paper as follows: section 2 describes detailed WorkowChecker design architecture, section 3 develops Touré-Baïna workflow verification algorithm and section 4 presents a demonstration example on which we base our tool demonstration. More theoretical aspects of WorkowChecker are to be found in [1].

Technological and Economic Development of Economy, 2012

Modeling of Business processes is essential in many areas. Workflows represent the Business processes. It is possible to identify potential problems while performing verification of workflows. One of the objectives of the verification is to assure reachability. This includes analysis of the deadlock and tempo blocking freeness properties. The paper presents verification approach based on using an adjacency matrix. Spreadsheets are used as a verification tool. The approach is illustrated by the examples which justify the importance of verification in workflow processes.

Conference on Advanced Information Systems Engineering, 2003

We describe a new approach to worko w analysis, which combines a rich graph representation of worko w schemes with simple (i.e., stratied), yet powerful DATALOG rules to express complex properties and constraints on execu- tions. Both the graph representation and the DATALOG rules are mapped into a unique program in DATALOGev!, that is a recent extension of DATALOG for

OOER'95: Object-Oriented and Entity …, 1995

Abstract. Workflow management is emerging as a challenging area for databases, stressing database technology beyond its current capabilities. Workflow management systems need to be more integrated with data management technology, in particular as it concerns the ...

2008

Graph transformation has recently become more and more popular as a general visual language to formally state the dynamic semantics of the designed models. Using this technique, we present a highly understandable yet precise approach to formally model the behavioral semantics of UML 2.0 Activity diagrams. Automated formal verification and analysis of UML Activities is the main advantage of our approach. In our proposal, AGG toolset is used to design Activities, then using our previous approach to model checking graph transformation systems, designers can verify and analyze designed Activity diagrams. One of the main application areas of the Activities is workflow modeling; hence to illustrate our approach, we use our proposed semantics for modeling and verification of workflows.

Journal of Software Engineering and Applications

Workflow-based systems are typically said to lead to better use of staff and better management and productivity. The first phase in building a workflow-based system is capturing the real-world process in a conceptual representation suit-able for the following phases of formalization and implementation. The specification may be in text or diagram form or written in a formal language. This paper proposes a flow-based diagrammatic methodology as a tool for workflow specification. The expressiveness of the method is appraised though its ability to capture a workflow-based application. Here we show that the proposed conceptual diagrams are able to express situations arising in practice as an alternative to tools currently used in workflow systems. This is demonstrated by using the proposed methodology to partial build demo systems for two government agencies.

This paper describes a case study involving interference between application activities and reconfiguration activities in an office workflow. We state the requirements on a system implementing the workflow and its reconfiguration, and describe the system's design in BPMN. We then use a number of computational formalisms of different kinds, including VDM and an asynchronous pi-calculus, to model the design and verify whether or not it will meet the requirements. In the process, we evaluate the formalisms for their suitability for the modelling and analysis of dynamic reconfiguration of dependable systems. We include in the evaluation, two process algebras we have been developing, namely, Webpi and CCSdp. Finally, we give an implementation of the system in BPEL.

We propose Concurrent T ransaction Logic (CTR) as the language for specifying, analyzing, and scheduling of work ows. We show that both local and global properties of work ows can be naturally represented as CTR formulas and reasoning can be done with the use of the proof theory and the semantics of this logic. We describe a transformation that leads to an e cient algorithm for scheduling work ows in the presence of global temporal constraints, which leads to decision procedures for dealing with several safety related properties such as whether every valid execution of the work ow satises a particular property or whether a work ow execution is consistent with some given global constraints on the ordering of events in a work ow. We also provide tight complexity results on the running times of these algorithms.

2004

Workflow technology has become a standard solution to managing increasingly complex business processes. Successful business process management depends on effective workflow modeling tools. Recently, researchers have developed a variety of workflow models, focusing mainly on the control and coordination of tasks, i.e. the control flow perspective. However, most of these workflow models found in the literature have paid little attention to the data flow perspective. In this paper, we investigate the data flow issues and propose a data flow modeling approach in the context of business process management. Our research objective is to develop a data flow modeling tool that supports data flow verification in workflow systems. Our contributions include also the classification of data flow operations and data flow anomalies.

A workflow is a collection of coordinated activities designed to carry out a well-defined complex process, such as trip planning, student registration, or a business process in a large enterprise. An activity in a workflow might be performed by a human, a device, or a program. Workflow management systems (or WfMS ) provide a framework for capturing the interaction among the activities in a workflow and are recognized as a new paradigm for integrating disparate systems, including legacy systems. A large workflow system might involve many disparate activities that are coordinated in complex ways and are subject to many constraints. Thus, modeling such systems and ensuring that they perform according to the specifications is not an easy task. To be able to analyze the properties of workflows, the latter must be specified using a formalism with well-defined semantics. The popular formalisms in this area are the various logics, Petri Nets [1,35], Event-Condition-Action rules , and State Charts . In this chapter we survey and compare a number of logic-based formalisms that were proposed in the literature.

Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 2006

The dynamic nature of incident command systems and their requirement for high flexibility raise a challenge to the research and implementation of workflows. The significance of applying formal approaches to the modeling and analysis of workflows has been well recognized and several such approaches have been proposed. However, these approaches require users to master considerable knowledge of the particular formalisms, which impacts their application on a larger scale. To address these challenges, we developed an intuitive, yet formal approach to workflow modeling, enactment and validation. In this paper, we further develop a set of theorems to support dynamic modeling, modification and on-the-fly verification of the workflows. A prototype has been implemented to demonstrate the feasibility of the theoretical approach.