Object-centric process models and the design of flexible processes

Mainstream business process modelling techniques promote a design paradigm wherein the activities to be performed within a case, together with their usual execution order, form the backbone of a process model, on top of which other aspects are anchored. This paradigm, while eective in standardised and production-oriented domains, shows some limitations when confronted with processes where case-by-case variations and exceptions are the norm. In this thesis we develop the idea that the eective design of exible process models calls for an alternative modelling paradigm, one in which process models are modularised along key business objects, rather than along activity decompositions. The research follows a design science method, starting from the formulation of a research problem expressed in terms of requirements, and culminating in a set of artifacts that have been devised to satisfy these requirements. The main contributions of the thesis are: (i) a meta-model for object-centric process modelling incorporating constructs for capturing exible processes; (ii) a transformation from this meta-model to an existing activity-centric process modelling language, namely YAWL, showing the relation between object-centric and activity-centric process modelling approaches; and (iii) a Coloured Petri Net that captures the semantics of the proposed meta-model. The meta-model has been evaluated using a framework consisting of a set of work ow patterns. Moreover, the meta-model has been embodied in a modelling tool that has been used to capture two industrial scenarios

A preliminary formalism for variable coupling in agile systems

It is generally the case that corporate information systems consist of heterogeneous software subsystems that interact using many various processes and protocols. Applications that execute within such subsystems tend to be designed in isolation with little or no thought given to the requirements for future interaction. To provide bridges between these heterogeneous subsystems, one-off "hacked" solutions are usually introduced which rely upon maintenance of the status quo for all aspects of the execution environment and are thus inherently "brittle". Such a situation is inappropriate for large-scale and highly decentralised system deployments. In order to make such systems more robust and exhibit scalable performance characteristics, it is preferable to construct them with the ability to react to changes in the environment that they operate within. This research seeks to provide a method of how to engender "agility" into system components to improve their ability to deal with unpredictable environments. Our approach is to view systems and components from an interactive perspective and provide a middleware mechanism that enables a "variable" degree of coupling between system components. To achieve this we introduce three high-level "dimensions" of coupling, namely mediation, adaptation and crystallisation. Each dimension is characterised by the location of behaviour required for interaction and patterns of behaviour movement. The coordination characteristics of these dimensions of coupling are specified to establish a separation of coordination and application functionalities in endogenous distributed systems. The outcomes of this research project are: a definition for the dimensions of coupling that have been identified, a protocol to perform transitions between dimensions and a preliminary framework for the development of more agile applications

Object-centric process models and the design of flexible processes

Mainstream business process modelling techniques promote a design paradigm wherein the activities to be performed within a case, together with their usual execution order, form the backbone of a process model, on top of which other aspects are anchored. This paradigm, while eective in standardised and production-oriented domains, shows some limitations when confronted with processes where case-by-case variations and exceptions are the norm. In this thesis we develop the idea that the eective design of \ud exible process models calls for an alternative modelling paradigm, one in which process models are modularised along key business objects, rather than along activity decompositions. The research follows a design science method, starting from the formulation of a research problem expressed in terms of requirements, and culminating in a set of artifacts that have been devised to satisfy these requirements. The main contributions of the thesis are: (i) a meta-model for object-centric process modelling incorporating constructs for capturing \ud exible processes; (ii) a transformation from this meta-model to an existing activity-centric process modelling language, namely YAWL, showing the relation between object-centric and activity-centric process modelling approaches; and (iii) a Coloured Petri Net that captures the semantics of the proposed meta-model. The meta-model has been evaluated using a framework consisting of a set of work\ud ow patterns. Moreover, the meta-model has been embodied in a modelling tool that has been used to capture two industrial scenarios