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With fast moving markets and increasingly global competition, companies now recognise that every aspect of a product, through its development and beyond, must be considered when making design decisions. Design for X tools are a popular way of doing this, providing information on how design choices affect subsequent lifephases or important virtues of the product. However, each DfX tool imposes a preference structure on the designers by giving precedence to a single virtue or lifephase, and offering no way of reconciling trade-offs with others. This thesis demonstrates that decision analysis - a technique for evaluating alternatives against conflicting objectives - can resolve this problem by incorporating DfX information in design decisions without imposing a preference structure. As many DfX techniques are available, attention is restricted to the context of integrated product and process design, where design decisions include the implications of manufacturing. Eight characteristics are proposed, taken from concurrent engineering principles and decision analysis, for successful integrated product and process design decisions. A relationship is shown to exist between DfX and decision analysis, and this relationship is embodied as a methodology for decision-making in integrated product and process design. Three Design Experiments and two Case Studies demonstrate that this methodology is feasible, and exhibits the desired characteristics in practice. Further work is necessary to determine whether these findings generalise to other DfX and whether this is an appropriate method of combination. Then future DfX tools could be developed based on decision analysis principles that can analyse designs systematically against multiple virtues and lifephases. By demonstrating the relationship between Design for X and decision analysis, and showing that it can be used in practice, this thesis provides the first step along this path.

The fertiliser industry is a significant contributor to the Indonesian economy. Given the need to distribute its products to customers on the 17,000 islands making up the Indonesian archipelago, capacity and availability of ports is a major factor in managing fertiliser product lifecycles and the supply networks. Fluctuations in the availability of infrastructure influence levels of risk in the supply networks. Supply network resilience is important to maintain the performance of the Indonesian fertiliser industry. Currently, decision makers in the Indonesian fertiliser industry use risk assessment reports to assess resilience. Discussions with Indonesian fertiliser industry managers highlighted a second, port management, report that is used to evaluate the availability of infrastructure. An opportunity was identified to use both reports in assessing resilience. This thesis is based on the premise that the risk assessment report can be used as an information resource for resilience assessment. A theoretical framework, based on a synthesis of literature and interviews with industry practitioners, is proposed. Results from interviews concluded that the supply network is a system consisting of social and technical factors. Thus, the approach needed to include both factors. Secondary data collected from risk assessment reports and primary data from brainstorming with key people in the industry were used to validate the approach. The theoretical framework was used to inform the construction of a conceptual model that was populated with data from a real-world case study. A simulation model was then built to translate the conceptual model into a practical application. The simulation model was used to investigate the results of the resilience assessment in different scenarios and predict levels of risk. Early feedback from Indonesian fertiliser industry practitioners indicated that the model could be valuable in the assessment of resilience. This research provides a new approach for managers to predict the level of risk in supply networks. Since the Indonesian fertiliser industry is owned and governed by the Indonesian state, the approach could be used by policy makers as a prototype to assess the current condition of the supply network in Indonesian industries and the output could be used to underpin the planning of supply networks in the future. For academia, the approach provides a new theoretical framework for research on supply network resilience and presents a real example of how agent-based modelling might be used as a tool to support the assessment of resilience.