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Title Modelling and Analysis of Business Workflows
Author Rasmussen, Thorbjørn Kamlarczyk
Supervisor Probst, Christian W. (Language-Based Technology, Department of Informatics and Mathematical Modeling, Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark)
Institution Technical University of Denmark, DTU, DK-2800 Kgs. Lyngby, Denmark
Thesis level Master's thesis
Year 2011
Abstract This thesis deals with the modelling and analysis aspects of business workfl ows. By a work ow is meant the structured organisation of work in order to produce some standardised service. There exists many different formalisms for modelling workfl ows. One of the most commonly used formalisms is (some extended version of) Petri net. The computational complexity of analysing a Petri net model is for many analyses very high. Work flows modelled by completely unrestricted Petri nets are therefore never used in practise, but Petri nets with restrictions like free-choice Petri nets are to model work flows in practise. There is thus always a trade-of between the expressive power of a modelling formalism and the computational complexity involved in analysing the expressed models. Since modelling and analysing workfl ows is a huge topic that have been studied for many decades, this thesis does not deal with all aspects work ow modelling and analysis. This thesis is focused on modelling the control-fl ow aspects of work flows using rewrite transition systems that are weaker than Petri nets. In particular, much of the thesis deals with modelling workflows using multiset automata and push-down automata. Perhaps not very surprisingly, modelling work flows using push-down automata turns out to be very inefficient for work flows with a substantial amount of concurrency. Using multiset automata to model workfl ows turns out to be problematic whenever there is a need for synchronisation of subprocesses. This thesis thus demonstrates why it is not very advisable to use push-down automata or multiset automata to model all types of workflows. But, since push-down automata, multiset automata, and Petri net are all rewrite transition systems, one can easily use a mixture of the formalisms to model different parts of a large work ow more efficiently than if one only uses Petri net. This thesis thus proposes a way of designing work flows in which push-down automata, multiset automata, and Petri net are mixed such that the formalism that leads to the fastest analyses for a given subprocess of a larger work ow is chosen.
Imprint Technical University of Denmark (DTU) : Kgs. Lyngby, Denmark
Series IMM-M.Sc.-2011-19
Original PDF ep11_19_net.pdf (0.58 MB)
Admin Creation date: 2011-04-04    Update date: 2011-04-04    Source: dtu    ID: 275886    Original MXD