Thesis (Ph.D.)--McMaster University, 2004. / Advisor: W. Poehlman. Includes bibliographical references (p. 189-195). Also available online.

Thesis (M.S.)--University of Alabama at Birmingham, 2006. / Description based on contents viewed Jan. 29, 2007; title from title screen. Includes bibliographical references.

Thesis (M.S.)--Ohio University, August, 2004. / Title from PDF t.p. Includes bibliographical references (p. 66-68)

Thesis (M.S.)--Ohio University, June, 2005. / Title from PDF t.p. Includes bibliographical references (p. 86-88)

Thesis (Ph. D.)--Civil and Environmental Engineering, Georgia Institute of Technology, 2007. / Bruce R. Ellingwood, Committee Chair ; Abdul-Hamid Zureick, Committee Member ; James I. Craig, Committee Member ; Reginald DesRoches, Committee Member ; Kenneth M. Will, Committee Member.

M. Phil. / Concrete is worldwide the most commonly used construction material and, although concrete is durable when exposed to aggressive conditions, it requires some maintenance. If this maintenance is neglected for a prolonged period of time, intrinsic and extrinsic factors will cause the concrete to degrade necessitating repair and rehabilitation. The correct diagnosis of the root cause of degradation, proper specification of repair materials and quality execution of the concrete repairs all contribute to the reliability of the repairs. The correct management of the repair process is necessary to ensure reliability in order for the structure to be returned to an acceptable state.

Optical fibre networks play an increasingly prominent role in communications. As networks grow in size and complexity, the probability and impact of failures increase. In this dissertation, different optical network concepts, survivability and resilience methods are considered. Link and Path failures are discussed and Static Path Protection (SPP), Shared Backup Path Protection (SBPP), as well as Path Restoration (PR) are investigated. A Shared Backup Path Protection model and simulation tool is designed and implemented. This implementation is compared with other studies. Dual-link failures are considered under specific network topologies. Shortest Path algorithms are used to reprovision optimal routes for backup protection. Results and conclusions are discussed in detail, giving valuable insight into resilience methods. Availability and protectability are discussed and evaluated as measures of resilience and network survivability. Results vary between compromising little availability and bringing a significant improvement in availability. It is concluded that the implementation of SBPP is a necessity in highly-meshed networks with high availability needs, but doesn’t necessarily provide the best solution for sparsely-connected networks. The additional cost involved in the implementation needs to be considered carefully. / Dissertation (MEng)--University of Pretoria, 2007. / Electrical, Electronic and Computer Engineering / unrestricted

Maintenance models are critical for evaluation of the alternative maintenance policies for modern engineering systems. A poorly selected policy can result in excessive life-cycle costs as well as unnecessary risks for catastrophic failures of the system. Economic dependence refers to the difference between the cost of combining the maintenance of a number of components and the cost of performing the same maintenance actions individually. Maintenance that takes advantage of this difference is often called opportunistic. Large number of components and economic inter-dependence are two pervasive characteristics of modern engineering systems that make the modeling of their maintenance processes particularly challenging. Simulation is able to handle both of these characteristics computationally, but the complexity, especially from the model verification perspective, becomes overwhelming as the number of components increases. This research introduces a new procedure for maintenance models of multi-unit repairable systems with economic dependence among its components and under opportunistic maintenance policies. The procedure is based on the stochastic Petri net with aging tokens modeling framework and it makes use of a component-level model approach to overcome the state explosion of the model combined with a novel order-reduction scheme that effectively combines the impact of other components into a single distribution. The justification for the used scheme is provided, the accuracy is assessed, and applications for the systems of realistic complexity are considered.

M.Phil. / “Failure is one of the unfortunate facts of life”. This is the very first statement in the book by Coetzee (1998). This statement is unfortunately true, leading to the fact that failure is a reality, to be dealt with. Dealing with it in a proactive way will provide warnings of an approaching failure. Dealing with it in a reactive way will go through the “surprising pain” of an unexpected breakdown or downtime. In both cases the source of failure must be known to prevent it from happening again. Root Cause Analysis (RCA) is a structured method of determining the reason (root cause) of a failure. On the other hand, Vibration Analysis is one of the best known methods of condition monitoring and has the capability to indicate a reason for failure, although not necessarily the root cause or causes. The objective of this dissertation is to investigate the possibility to combine the RCA method with Vibration Analysis as forensic science to improve the success of finding root causes and their solutions.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1982. / Includes bibliographical references. / by Xi-Cheng Lou. / M.S.