Dynamic process modelling for business engineering and information systems evaluation

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.This research is concerned with the pre-implementation evaluation of investments in Information Systems (IS). IS evaluation is important as organisations need to assess the financial justifiability of business change proposals that include (but usually are not limited to) the introduction of IS applications. More specifically, this research addresses the problem of benefits assessment within IS evaluation. We contend that benefits assessment should not be performed at the level of the IS application, as most extant evaluation methods advocate. Instead, to study the dynamics and the interactions of the IS applications with their surrounding environment, we propose to adopt the business process as the analytic lens of evaluation and to assess the impacts of IS on organisational, rather than on technical, performance indicators. Drawing on these propositions, this research investigates the potential of dynamic process modelling (via discrete-event simulation) as a facilitator of IS evaluation. We argue that, in order to be effective evaluation tools, business process models should be able to explicitly incorporate the effects of IS introduction on business performance, an issue that is found to be under-researched in previous literature. The above findings serve as the central theme for the development of a design theory of IS evaluation by simulation. The theory provides prescriptive elements that refer both to the design products of the evaluation and the design process by which these products can come into reality. The theory draws on a set of kernel theories from the business engineering domain and proposes a set of meta-requirements that should be satisfied by business process models, a meta-design structure that meets these requirements, and a design method that provides guidance in applying the theoretical propositions in practice. The design theory is developed and empirically tested by means of two real-life case studies. The first study is used to complement the findings of a literature review and to drive the development of the design theory's components, while the second study is employed to validate and further enhance the theory's propositions. The research results support the arguments for simulation-assisted IS evaluation and demonstrate the contribution of the design theory to the field

Focus Issue on Legacy Information Systems and Business Process Change:On the Integrated Design and Evaluation of Business Processes and Information Systems

The role of information systems in influencing and enabling organisational design is widely acknowledged. Yet limited attention is paid to the theoretical legitimacy and conceptual basis of IS-enabled organisational change i.e., business engineering. In this paper we review business engineering\u27s reference disciplines critically: process-based organisational design, IS development, and IS evaluation. Findings from a case study of business engineering provide empirical support to the theoretical analysis. Synthesis of the conclusions of the review and the case study lead to a number of propositions and potential avenues for further research into the theoretically attractive and practically important field of aligning the design of organisational structures with the design of Information Systems intended to support them

Simulation for business processes and information systems design

Business Process (BP) literature promotes the value of business processes as essential gearwheels that help organizations to reach their goals. Similarly, many process design approaches claim that Information Technology (IT) is a major enabler of business process, a view also shared by the Information Systems (IS) community. Despite this, BP and IS approaches do not provide clear guidance on how to assess the benefits that a given IS design may bring to the BP prior the IS implementation. Nor is clear indication of which modeling techniques could be used to assess such relationship. This paper uses the insights gained during a UK funded research project, namely ASSESS-IT, that aimed to depict the dynamic relationships between BP and IT to propose an alternative framework to develop BP simulation models that depict the dynamic behavior of the relationships between BP and IS

Understanding the effects of e-business on business processes, a simulation approach

This thesis defines a new approach to the analysis of the effect of e-business on business processes, utilising simulation as evaluation tool. This research was focused on answering five research questions about the suitability of simulation in this context, the role of static modelling and generic business processes, the identification of patterns for e-business activities and how to operationalise these patterns into components in simulation software, as well as how to use these components. Requirements for modelling of e-business processes were identified and documented. Pilot cases studies proved the potential of simulation for studying e-business processes (Feasibility). Generic e-business activities were derived and classified from the literature and case studies in order to fill gaps identified in existent process models. Re-usable simulation components are proposed as a result of the unique combination of simulation and e-activities in order to make simulation modelling of e-business easier. The components were tested in industrial case studies and quasi-experiments with end users for feasibility, usability and usefulness. Results show that the components' approach is feasible, that having re-usable components promotes a better analysis, (usefulness) and that it is easy to build models using the components (usability). The theoretical novelty of this research resides in bringing together three areas of study: ebusiness, simulation and business processes to analyse e-business implementations. The research contributes to the knowledge of components and re-use theory in simulation by proposing a new approach to component development, operationalisation and analysis of the degree of granularity required for these components. From a practical point of view, this research provides companies with an easier and more complete way of analysing e-business processes, breaking the barrier for the use of simulation, speeding up model building of eprocesses and getting a better understanding of the dynamics of e-processes. Future work in the area will include extending the component approach to supply chains and inter-company transactions.This thesis defines a new approach to the analysis of the effect of e-business on business processes, utilising simulation as evaluation tool. This research was focused on answering five research questions about the suitability of simulation in this context, the role of static modelling and generic business processes, the identification of patterns for e-business activities and how to operationalise these patterns into components in simulation software, as well as how to use these components. Requirements for modelling of e-business processes were identified and documented. Pilot cases studies proved the potential of simulation for studying e-business processes (Feasibility). Generic e-business activities were derived and classified from the literature and case studies in order to fill gaps identified in existent process models. Re-usable simulation components are proposed as a result of the unique combination of simulation and e-activities in order to make simulation modelling of e-business easier. The components were tested in industrial case studies and quasi-experiments with end users for feasibility, usability and usefulness. Results show that the components' approach is feasible, that having re-usable components promotes a better analysis, (usefulness) and that it is easy to build models using the components (usability). The theoretical novelty of this research resides in bringing together three areas of study: ebusiness, simulation and business processes to analyse e-business implementations. The research contributes to the knowledge of components and re-use theory in simulation by proposing a new approach to component development, operationalisation and analysis of the degree of granularity required for these components. From a practical point of view, this research provides companies with an easier and more complete way of analysing e-business processes, breaking the barrier for the use of simulation, speeding up model building of eprocesses and getting a better understanding of the dynamics of e-processes. Future work in the area will include extending the component approach to supply chains and inter-company transactions

Copula-based stochastic modelling of evapotranspiration time series conditioned on rainfall as design tool in water resources management

In the last few decades, the frequency and intensity of water-related disasters, also called climate-related disasters, e.g. floods, storms, heat waves and droughts, has gone up considerably at both global and regional scales, causing significant damage to many societies and ecosystems. Understanding the behavior and frequency of these disasters is extremely important, not only for reducing their damages but also for the management of water resources. These disasters can often be characterized by multiple dependent variables and therefore require a flexible multivariate approach for studying such phenomena. In this study, we focus on copulas, which are multivariate functions that describe the dependence structure between stochastic variables, independently of their marginal behaviors. The study aimed at different potential applications of copulas in hydrology, such as a multivariate frequency analysis and a copula-based approach for assessing a rainfall model. And further, a stochastic copula-based evapotranspiration generator was developed. As an application, the potential impacts of climate change on river discharge was investigated partly based the latter generator

Thermal improvement of existing dwellings

This report describes the outcome from a study to determine the impact of energy efficiency measures applied to the Scottish housing stock. Assuming conventional property type classifications, the present performance of the housing stock is quantified using available survey data. Building simulation techniques were then employed to generate a Web-based, decision-support tool for use by policy makers to estimate the impact of deploying energy efficiency measures in different combinations over time. The process of tool formulation is described and an example is given of tool use to identify best-value retrofitting options while taking factors such as future climate change and improved standard of living into account

Stochastic information technology modelling for business processes

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.Business Processes (BP) and Information Technology (IT) are two areas that work very closely in helping organisations to keep or retain competitive advantage. Therefore, design in these areas should consider the advantages provided by, and the limitations that each of these domains imposes on each other. BP design tries to ensure that IT specifications are considered during the design of BP. Similarly, Information Systems (IS) design attempts to capture organisational needs, known as IS functional and Non-Functional Requirements (NFR), in order to meet the organisational goals. Despite this, BP and IT modelling techniques barely depict the way IT may affect BP performance or vice versa. For example, Business Process Simulation (BPS) is one of the modelling techniques that has been increasingly used to support process design. The performance measurements obtained from BPS models, though, are obtained considering only organisational issues, and thus cannot be used to assess the impact that IT may have on process performance. Similarly, IT modelling techniques do not provide IS performance measurements, and hence cannot depict the way IS may improve BP performance. The relationship between BP and IT can be alternatively described in terms of the relationships between BP, IS and Computer Networks (CN). By looking at the parameters that govern these relationships a simulation framework was developed, namely ASSESS-IT, that develops simulation models that provide performance measurements of BP, IS and CN, and thus can reflect the impact that IT (IS and CN) may have on BP performance. This research uses a case study to test the proposed framework (theory testing), to understand the way BP, IS, and CN domains interact (discovery), and to propose alternative theories to solve the problems found (theory building). The experimentation with the ASSESS-IT framework suggests that in order to portray the impact that IT may have on BP, analysts in these domains should first identify those performance specifications that describe how well the IS delivers its functionality (also known as non-functional requirements). It was found that when the IS does not depend on determined response time, the relationships between BP, IS and CN can be assessed using only the relationship between BP and IS. An alternative simulation framework, namely BPISS, is proposed to produce BPS models that provide performance measurements of BP and IS. Thus, BP and IT analysts can investigate the impact that a given IS design may have on BP performance, and identify a better BP and IS solution.CONACYT, Mexic