Capacity pooling in production systems, in the form of production capacity or inventory pooling, has been extensively studied in the literature. While production capacity pooling has been proven to be beneficial, the impact of inventory pooling has been less significant. These results cannot be easily extended to repairable systems due to fundamental differences between repairable and production systems. For one thing, in repairable systems, the demand rate is a function of the number of operational machines, whereas it is exogenous and constant in production systems. In this Thesis, to serve different fleets of machines possibly at different locations, we study whether repair shop pooling is more cost effective than having dedicated on-site repair shops for each fleet. In the first model, we consider transportation delays and related costs, which have been traditionally ignored in the literature. We include on-site spare-part inventories that operate according to a continuous-review base-stock policy. Our numerical findings indicate that when transportation costs are reasonable, repair shop pooling is a better alternative. Next, we model a pooled repair shop that fixes failed components from different k-out-of-n:G systems. We permit a shared spare parts inventory serving all systems and/or reserved spare parts inventories for each system; we call this a hybrid model. The destination for a repaired component can be chosen either on a first-come-first-served basis or by following a static priority rule. Our findings show that both hybrid policies are more cost effective than having separate repair shops and inventories for each system. We propose implementing the multilevel rationing (MR) policy in systems with shared inventory. The MR policy prioritizes classes, and stops serving a class from inventory if the inventory level is below the inventory threshold identified for that class. When there is no inventory, the repaired component is sent to the highest priority class among those with down machines. To approximate the cost of the MR policy, we study an M/G/1//N queueing system serving multiple classes of customers with an unreliable server. Our numerical findings indicate that the MR policy performs as well as the epsilon-optimal policy and outperforms the hybrid policies.

Much study is required on how human behaviour affects resource consumption. Not only are Human Factors Engineers well equipped to study how to shape human behaviour, but contributors to conservation literature have asked for their involvement in the domain of energy conservation. This study took a novel, systematic, human-factors approach to providing feedback on energy consumption by testing the effects of providing three levels of feedback on conservation performance. The results showed that providing physical, functional, and task-based information aided performance more than physical information alone, but no more than providing physical and functional information together. More research is required to determine if physical and task information alone could achieve the same result, if study results would differ when two opposing task goals were given, and if the varying levels of feedback have a greater effect on novices.

In response to growing concerns over the susceptibility of water distribution systems to contamination, this thesis presents the design and evaluation of an ecological display for an intelligent water monitoring system. Work Domain Analysis and Control Task Analysis were used to uncover the information requirements of the display. The work domain model in this thesis is one of a limited number of such models to include a representation of the automation. The resulting ecological display was evaluated in a comparative usability study against an alternative display based on a competitor’s product. Nine certified water operators participated. The displays were compared across three categories of usability measures: effectiveness, efficiency, and satisfaction. No significant differences were observed. The results, however, helped identify design changes for the display. The implications for the design of intelligent automation displays, and the challenge of designing displays in parallel with early development of automation systems, are discussed.

In 2008 Ontario implemented a screening program for colorectal cancer, which drew attention to the increasing demand for colonoscopies in the province. This trend and the forecasted demand of the new screening program created a need to increase capacity in hospital endoscopy suites. This thesis addresses this need by investigating throughput gains from scheduling according to physician specific procedure durations in endoscopy suites. This is accomplished through the development of a scheduler and a generic discrete event simulation. Case study results show that physician specific scheduling can increase throughput in the endoscopy suite while reducing undertime and only slightly increasing overtime. They further indicate the trade off between a 1:2 and 1:1 physician to room ratio, finding that while a 1:1 ratio increases throughput by 33% over a 1:2 ratio, physicians are 1.5 times more productive under a 1:2 ratio.

A margin account is a type of brokerage account that allows investors to buy and sell financial securities using credit. The account’s margin requirement is the amount of collateral required, from the investor, to cover the funds or securities extended by the broker to the investor. In Canada, the primary driver of an account’s margin requirement is the account’s Capital Charge [CC] which is calculated using a set of regulatory rules. The regulations are degenerate in that hundreds of valid CCs often exist for a single account. This work outlines a linear optimization model for selecting the minimal CC out of the set of valid CCs for a given margin account. The method proposed is consistent with all of the regulatory requirements and is guaranteed optimal in most cases. Relative to existing methods, the new method produced an average CC reduction of approximately 2% and displayed qualitatively better run-times.

Despite years of research in residential energy conservation, means of inducing conservation behaviour through feedback are not well understood. In this thesis I take a novel approach to feedback design by addressing temporal inconsistencies that may hinder individuals from forming an intention to conserve. To help understand conservation compliance strategies, I proposed a visual framework to categorize interventions. I present two design heuristics that were inspired by temporal construal theory (Liberman & Trope, 2003). They were the impetus for the design of three feedback display prototypes, which were examined. Due to methodological limitations, significant improvements to compliance were not found. However, evidence suggests that comparative feedback may have supported reasoning about conservation rather than supporting conservation compliance directly. Future work includes refinement of feedback displays to avoid direct comparisons, exploring the use of nature imagery, and the study of a possible interaction between environmental values and comparative feedback on compliance.

Real options analysis has been recommended to identify and quantify opportunities where managerial flexibility can influence worth. However, real options models in the literature have become increasingly sophisticated, and managers have cited their reluctance to use such models due to their level of complexity and lack of transparency. Presented in this thesis is a real options model that can be easily incorporated into the current project selection methodology of a firm; the model uses managerial cash flow estimates to price real options on tangible investment opportunities in a financially consistent manner. Next, to demonstrate the application of real options analysis in practice, five real options models, including the proposed model, are applied to value a medical device project. The models all price the real option differently, due to the differences in their underlying assumptions, but they all yield the same investment conclusion: the medical device project has value.

This work focuses on the presentation of a methodology for the development and verification of expressive ontologies. Motivated by experiences with the development of first-order logic ontologies, we call attention to the inadequacies of existing development methodologies for expressive ontologies. We attempt to incorporate pragmatic considerations inspired by our experiences while maintaining the rigorous definition and verification of requirements necessary for the development of expressive ontologies. We leverage automated reasoning tools to enable semiautomatic verification of requirements, and to assist other aspects of development where possible. In addition, we discuss the related issue of ontology quality, and formulate a set of requirements for MACLEOD - a proposed development tool that would support our lifecycle.

Linear assets are among the largest and most important engineered systems; their reliability is of the utmost importance. This thesis presents an overview of the reliability estimation methods used for the various types of linear assets, both observation- and statistically-based. While observation-based reliability monitoring and estimation methods are necessarily particular to a certain type of asset, statistically-based methods developed for one type can potentially inform those used for another. Therefore, this thesis looks to point out commonalities in the methods for the statistical evaluation of the reliability of various types of linear assets, develop and extend reliability models and methods with this knowledge, and suggest how maintenance strategies may be improved. To help illustrate and test the models described in this paper a case study was conducted with a utility operator; this thesis shows the modelling results from the study, and demonstrates the model’s use in a maintenance decision model.

This thesis investigates the effect of a feedback-reward system on speeding and tailgating behaviours. Data utilized in this study were collected from 37 participants through a field trial commissioned by Transport Canada. In this trial, a feedback-reward system was investigated, which provided feedback and rewards to the drivers based on speed limit compliance and safe headway maintenance. The trial consisted of three phases: baseline, intervention, and post-intervention. During the intervention phase, real-time feedback was provided on an in-vehicle display. Participants also accumulated reward points and could view related information on a website. Results indicate that the intervention resulted in a significant increase in speed limit compliance, and this positive effect, although dampened, was still apparent after system removal. Similarly, results on headway compliance rate indicate a positive intervention effect, however, this effect did not sustain after system removal. These findings have implications for developing better aids to improve driving behaviour.