Workflow Model Analysis And Flexibility Research Based On Artifact Dependent Relationships

With the development of information technology,enterprises are more likely to run business based on the information platform.Workflow Management System accelerates the speed of making profit,so it has become one of the most important parts in enterprises.The changing of business surroundings arouses the changing of business demand,which in turn challenge the traditional workflow management system.The challenge is that workflow management system will not only meet the demand of static workflow model,but also meet the demand of dynamic workflow model,and it will be the trend that workflow management system's characteristic becomes flexibility from rigidity.There are many aspects of the research about flexibility of workflow management system,in which,dynamic change is the essence. Actually the structural change of workflow model,contained in dynamic change, appears more often,so it is significant that doing research about the structural change of workflow model.Workflow Model is the essence of the workflow management system.The structural change is based on some workflow model,because workflow management system runs based on some workflow model.The research about flexibility of workflow model started since the 1990s.SOA and Web Service become more and more popular,which makes workflow management system integrate SOA. ACOM(Artifact-centered Oriental Model) is such a workflow model.But ACOM model has just started doing research about flexibility,so the paper extends ACOM model in the flexibility aspect.The paper proposes a novel model which is called BR-artifact model based on ACOM model.The paper analyses the artifact dependent relationships and the relationships between artifacts and tasks defined by the business rules.The paper shows that artifact instances can reach to final states along life-cycle through tracking key artifact.In the meanwhile,the paper proposes four theorems that structural change on BR-artifact model should keep,necessary and sufficient conditions based on the four theorems,and algorithms.Finally,we design the experiments about BR-artifact model's structural change on YAWL open-source system,including deleting service,adding service,preposing service,paralleling service.The experiments,on both levels of model specification and model case,show that BR-artifact model is flexible.