Reserch On Time Management Algorithms In Workflow Systems

Lack of support for time management has been identified as one of the most significant shortages of today's workflow management systems, and also a serious limitation in applying workflow technologies to complex enterprises. Doing researches on workflow time management is important to enriching the theory of workflow modeling, to enhancing the flexibility and practicality of workflow management software systems, to guarantying workflow plans to be efficiently executed, and to making enterprises more competitive. Consistency verification for workflow temporal constraints and scheduling for temporal constraint workflows have been deeply researched in this paper.The main contributions of the paper are listed as follows.(1) Based on the basic theory of temporal constraint networks, two operations,"partially join"and"split", have been presented and deeply analyzed. Operating theory of temporal constraint networks has been extended to fit for reasoning in workflow temporal constraints.(2) Based on the TCN operations—"partially join"and"split", a TCN-based verification algorithm—WFTCCV has been presented for verifying the consistency of workflow temporal constraints, in which a workflow with several instance types is considered as a whole, to make up the shortage in traditional methods.(3) A TCN-based scheduling algorithm—TCWFS has been presented for making optimized plans for activity executions in temporal constraint workflows, in which the current executing states of activities have been considered completely, to make up the shortage in relative researches.