Thesis (M.S.)--Rutgers University, 2007. / "Graduate Program in Mechanical and Aerospace Engineering." Includes bibliographical references (p. 108-111).

Thesis (Ph.D)--Mechanical Engineering, Georgia Institute of Technology, 2010. / Committee Chair: Samuel Graham; Committee Member: Bernard Kippelen; Committee Member: David McDowell; Committee Member: Sankar Nair; Committee Member: Suresh Sitaraman. Part of the SMARTech Electronic Thesis and Dissertation Collection.

Thesis (M.S.)--Rochester Institute of Technology, 2005. / Typescript. Includes bibliographical references (leaves 119-122).

Thesis (M.Eng.)--Memorial University of Newfoundland, 2003. / Bibliography: leaves 117-123. Also available online.

Thesis (M.Sc.)--York University, 2005. Graduate Programme in Physics and Astronomy. / Typescript. Includes bibliographical references (leaves 110-116). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11860

D.Phil. / The thesis provides an overview on the problem of component obsolescence (electronic and other types of components) in the South African context. By assessing applicable literature as well as feedback and lessons learned from relevant projects, a model for the management of component obsolescence is proposed. The aim of the research is to provide a definition of component obsolescence drivers and to formulate a model for the management of component obsolescence. Guidelines on how these management activities can be optimised in the different life cycle phases of projects in order to reduce applicable obsolescence risks are provided. A costing model to calculate the applicable costs associated with component obsolescence in the South African context is also proposed. In order to implement successful obsolescence management, the following approach is proposed: Ensure that the drivers of component obsolescence supported by a costing model to calculate the applicable obsolescence costs, and the possible impact thereof, is made visible to applicable levels of management; Encourage projects to support a process that is directed at addressing obsolescence risks applicable to that project by introducing obsolescence management as an important part of the Through Life Support (TLS) planning of all long-term projects or complex equipment; Promote an environment where obsolescence management is an integral part of the system engineering process so as to optimise the rapid development processes (especially for electronic components) whilst also keeping support expenditure within acceptable limits; Adequate funding should be allocated to ensure that obsolescence risks and activities can be identified, addressed and monitored cost effectively over the complete life cycle of the product or system from initial design to end of support or phase-out of the system.

M.Phil. / This dissertation provides an overview on the problem of electronic component obsolescence from a military product support perspective. By assessing applicable literature as well as feedback and lessons learned from relevant support projects, a strategy for the management of component obsolescence is proposed. The aim of the research is to provide a definition of component obsolescence drivers and to formulate a strategy for the management of component obsolescence within a military electronic support environment. The strategy will give guidelines on how management activities can be optimised to reduce applicable obsolescence risks and thereby reducing related life cycle costs. In order to implement a successful obsolescence management process (OMP), the following approach is proposed: Ensure that the drivers of component obsolescence and the possible impact there of will be made visible to applicable levels of management. Promote an environment where obsolescence management is an integral part of the system engineering process so as to optimise the rapid electronic development process whilst also keeping support expenditure within acceptable limits. Encourage projects to support a process that is directed at addressing obsolescence risks applicable to that project. Introduce OMP as an important part of the Through Life Support (TLS) planning of projects. Materials management should be encouraged to implement a process where interfacing with suppliers will address obsolescence risks. This typically includes a feedback loop regarding component usage patterns, component end of production notifications, component substitutions and other related component supplier information. Adequate funding must be allocated to ensure that obsolescence risks and activities can be addressed cost effectively over the complete life cycle of the product or system from initial design to end of support.

This investigation addresses the problem of numerically predicting the heat transfer rates between parallel surfaces of the type found in electronic equipment. This has been accomplished through a unique application of the finite-element method for transient or steady-state, two-dimensional mixed convection heat transfer with surface radiation. The approach was specifically geared toward implementation on present engineering workstations. Results are presented for mixed-convection in vertical channels using the full-elliptic form of the Navier-Stokes equations with radiation effects included. The results show that the heat transfer and flow solutions can be significantly affected when not using common approximations and simplifications. / Ph. D.

Stress sensitivity of a 16 - bit D/A converter in a molded plastic DIP has been studied. Device performance was shown to change as a function of package stress. The effects of die position in the package and the presence or absence of die coat on package stress and device performance were determined. Finite element methods were employed for system analysis. Device stress sensitivity was attributed to diffused bit transistors and the mechanism assigned to nonuniformity of stress on the device bit transistors. Die coat (silicone gel) was shown to reduce normal and shear stresses and have little or no effect on X-axial stresses. Lowering the die in the package was shown to increase the X-axial stress uniformity from the die center to edge for die-coated parts and alter the value of shear stresses near the die edge for parts without die coat.

Aerosol particle deposition rates on surfaces inside a clean room are predicted by a model developed to account for particle convection, diffusion and sedimentation. External forces acting on the particle also influence the rate of deposition. Both electrical charge build up on product surfaces and temperature gradients in the air near the product surface are known to effect the rate of deposition. A description of an electrostatic and thermophoretic force on the particle is thus included in the model. The equations governing the particle deposition process and the approach used in obtaining a solution to these equations are both described. A finite element numerical solution is detailed, followed by a description of the electrostatic force models. Finally, predictions of the model are presented with a comparison to data experimentally obtained by other researchers.