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Full-Text Articles in Engineering
Phonon-Energy-Coupling-Enhancement Effect And Its Applications, Pang-Leen Ong
Phonon-Energy-Coupling-Enhancement Effect And Its Applications, Pang-Leen Ong
University of Kentucky Doctoral Dissertations
Silicon Oxide/Oxynitride (SiO2/SiON) has been the mainstream material used for gate dielectric for MOS transistors for the past 30 years. The aggressive scaling of the feature size of MOS transistor has limited the ability of SiO2/SiON to work effectively as the gate dielectric to modulate the conduction of current of MOS transistors due to excess leakage current dominated by direct quantum tunneling. Due to this constraint, alternative gate dielectric/high-k is being employed to reduce the leakage current in order to maintain the rate of scaling of MOS transistors. However, the cost involved in the implementation of …
Modular Fast Direct Analysis Using Non-Radiating Local-Global Solution Modes, Xin Xu
Modular Fast Direct Analysis Using Non-Radiating Local-Global Solution Modes, Xin Xu
University of Kentucky Doctoral Dissertations
This dissertation proposes a modular fast direct (MFD) analysis method for a class of problems involving a large fixed platform region and a smaller, variable design region. A modular solution algorithm is obtained by first decomposing the problem geometry into platform and design regions. The two regions are effectively detached from one another using basic equivalence concepts. Equivalence principles allow the total system model to be constructed in terms of independent interaction modules associated with the platform and design regions. These modules include interactions with the equivalent surface that bounds the design region. This dissertation discusses how to analyze (fill …
Role Of Dipoles In The Bulk Phosphor Layer In The Electroluminance Mechanisms Of A.C. Thin Film Electroluminescent Display Devices, Praveen Kumar Sivakumar
Role Of Dipoles In The Bulk Phosphor Layer In The Electroluminance Mechanisms Of A.C. Thin Film Electroluminescent Display Devices, Praveen Kumar Sivakumar
University of Kentucky Doctoral Dissertations
The purpose of this dissertation is to advance the understanding of SrS-based a. c. thin film electroluminescent (ACTFEL) devices. The role of traps in the bulk phosphor layer in the light emission mechanism from ACTFEL devices is studied, characterized and modeled.
Experiments were performed to observe the response of the ACTFEL devices to tailored voltage excitations. A physical model was developed to describe the optoelectronic processes taking place in the phosphor; analytical equations were written and numerically simulated to plot the flux and luminance responses of the device to similarly tailored voltage excitations.
The voltage excitation parameters such as amplitude, …
Dual Bypass Gas Metal Arc Welding Process And Control, Xiaopei Liu
Dual Bypass Gas Metal Arc Welding Process And Control, Xiaopei Liu
University of Kentucky Doctoral Dissertations
GMAW (Gas Metal Arc Welding) is one of the most important arc welding processes being adopted in modern manufacturing industry due to its advantages in productivity, energy efficiency and automation. By monitoring and improving some of the important properties of GMAW such as production rate, metal transfer and base metal heat input, researchers could bring the process efficiency and stability to a new level. In recent years, some innovative modifications of GMAW such as Twins, Tandem and laser-MIG hybrid welding have been adopted into many industrial applications for better productivity.
In this dissertation, a novel GMAW called DB-GMAW (Dual Bypass …