1







The Hong Kong University of Science and Technology
Department of Computer Science

PhD Thesis Proposal Defence

"Temporal & Speed Up Aspects in Workflow Management Systems"

By

Miss Eleana Kafeza

Abstract

The need for explicit time management in workflow environments has been recently identified. Introducing time management in WFMSs has two aspects a) allowing the specification and support of advanced temporal constraints and b) allowing the acceleration (speed-up) of already executing workflow instances.

Recently it has been argued that advanced workflow applications (e.g. health care, GIS, cross-organisational applications) are time constrained but existing approaches focus on incorporating quantitative temporal constraints and do not consider qualitative aspects. In this thesis we incorporate a subset of interval algebra in workflow specification, we develop a consistency-checking mechanism that verifies the consistency of the specification and we examine different scheduling mechanisms based on different application requirements.

The second aspect of time management arises in the context of e-commerce workflow applications. With the rapid development of the electronic marketplace, companies have to adjust to a global, highly competitive and dynamic environment. Hence, it is critical for WFMSs to be capable of providing scheduling policies that allow accelerating e-commerce applications according to "on-line" speed-up requests. In this thesis, we formulate the problem of speeding-up without acquiring any additional resources in a multi-agent environment, where each agent is responsible for speeding-up local tasks residing in its input queue. We model the concept of speed-up, and of activity speed-up dependencies i.e. dependencies that arise due to speed-up requests. We examine the applicability of our model when agents can delegate sub-activities to other agents. We present a cost model for satisfying speed-up requests by calculating the resultant slow-down to other concurrently executing activity instances. We describe algorithms, that consistently and efficiently speed-up activities. We evaluate our results through simulation.

		Date:				Monday, 25 September 2000

		Time:				2:30p.m.-4:30p.m.
	
		Venue:				Room 3408
						Lifts 17-18

		Chairman:			Dr. Chi-Keung Tang

		Committee Members:		Dr. Kamalakar Karlapalem (Supervisor)
						Prof. Dik-Lun Lee
						Prof. Frederick Lochovsky
						Dr. Jogesh Muppala


**** ALL are Welcome ****
??