This dissertation explores the use of the efficiency performance measurement paradigm (EM), in terms of its concepts and applications, as an ex-ante mechanism to evaluate enterprise performance and inform enterprise design. The design of an enterprise is driven by decisions that include, but not limit to, which strategies to implement, how to allocate resources, how to shift operating patterns, and how to boost coordination among enterprises, among others. Up to date, EM has been mainly used as a descriptive mechanism, but the fundamental reason for measuring performance in an ex-post fashion, i.e., how well an enterprise does, is also valid in the context of design decisions, i.e., ex-ante evaluation. The contrast between the ex-post and ex-ante use of EM relates to the measurement purpose, i.e., why to measure. Ex-post measurement focuses on evaluating 'what happened' (non-disruptive) while ex-ante measurement emphasizes in informing design decisions exploring changes in current settings (more disruptive). Within this context and to achieve the purpose above, this dissertation is supported by theoretical insights and complemented with three empirical studies. The theoretical insights relate to facts that support, connect to, and challenge (i.e., facilitate or impede) the ex-ante use of EM for enterprise evaluation and informing enterprise design. Those insights are based on the efficiency performance measurement, organizational design and enterprise systems engineering literature. Meanwhile, the three empirical studies situate the application of EM as an ex-ante mechanism to inform evacuation management, bank branch management, and power plants. The theoretical and empirical results indicate that EM is well suited for both evaluating enterprise performance and informing design decisions. The main contribution of this dissertation to enterprise stakeholders is that EM can be not only used to answer how well the enterprise did, but also how well it could do if certain design decisions are taken. / Ph. D.

This research explores the effect of proposed management policies and related structures on the dynamics of value streams, particularly under demand instability. It relies on methods from the systems thinking and modeling literature and was designed to fulfill three main objectives. Objective 1: Provide insight into the causes of problematic behavior in traditional value streams. Objective 2: Identify modes of demand behavior suitable for pull-based systems operation. Objective 3: Propose and test alternative value stream management policies and structures. The achievement of objectives 1 and 3 required the fulfillment of both a hypothetical and a real case. The hypothetical case was designed to describe the problem and improvement alternatives in generic terms, whereas the real case served to contextualize the main generic modeling elements in a real world situation, thus serving as an illustrative example. The research approach was one based on system dynamics modeling and simulation methodologies that reflect the scientific method. Three alternative policies were created and tested. Policy 1: a decision rule for altering the number of kanbans in circulation at the protective decoupling inventory during production cycles. Policy 2: a decision rule for defining the amount of demand to include in value stream schedules. Policy 3: a decision rule for setting a purposefully unbalanced downstream production capacity. The results suggest a benefit from the combined use of Policies 2 and 3 in the face of sudden demand peaks. Policy 1 is expected to provide minor benefits but also significantly increase the risk of upstream instability and therefore its use is not recommended. This study provides a causality perspective of the structure of value streams, and gives enterprise engineers new insights into the state-of-the-art in value stream design. / Ph. D.

This thesis explores the potential to unify three emerging disciplines: enterprise engineering, enterprise architecture and enterprise ontology. The current fragmentation that exists in literature on enterprise alignment and design constrains the development and growth of the emerging disciplines. Enterprises need to use a multi-disciplinary approach when they continuously align, design and re-design the enterprise. Although enterprises need to be aligned internally (across various enterprise facets), as well as externally (with the environment), most alignment approaches still focus on business-IT alignment, i.e. aligning the business operations with the information and communication technologies and systems of the enterprise. This study focuses on a popular business-IT alignment approach,called the foundation for execution approach, and its associated artefact, called the operating model. The study acknowledges the theoretical contribution of the operating model to establish the required level of business process integration and standardisation at an enterprise in delivering goods and services to customers. Highlighting the practical problems in selecting an operating model for an enterprise, and more specifically the practical problems of identifying process reuse potential at an enterprise, a thesis statement is formulated: The operating model concept, as part of a business-IT alignment approach, can be enhanced with a process reuse identification framework, when a business-IT alignment contextualisation is used. The study is divided into two research questions. The first research question addresses the current fragmentation that exists in the literature, which impairs reuse of the existing business-IT alignment knowledge base. An inductive literature review develops the Business-IT Alignment Model to provide a common contextualisation for current business-IT alignment approaches. The second research question addresses the practical problems of the operating model regarding the identification of process reuse potential at an enterprise. Applying the newly developed Business-IT Alignment Model as a contextualisation instrument, the study demonstrates the use of design research in developing the Process Reuse Identification Framework. The conclusion after the investigation of the two research questions is that the thesis statement was confirmed, i.e. the operating model concept, as part of a business-IT alignment approach, can be enhanced with a process reuse identification framework, when a business-IT contextualisation is used. / Thesis (PhD)--University of Pretoria, 2013. / Industrial and Systems Engineering / Unrestricted