Lai Yuen-hoo. / Thesis submitted in: November 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 100-102). / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.ii / Acknowledgment --- p.iii / List of Figures --- p.iv / Table of Content --- p.vii / Chapter 1. --- Introduction --- p.1 / Chapter 1.1. --- Problem Definition --- p.1 / Chapter 1.2. --- Proposed Solution --- p.2 / Chapter 1.3. --- Thesis Contributions --- p.2 / Chapter 2. --- Modeling Approaches --- p.4 / Chapter 2.1. --- Polygon Modeling --- p.4 / Chapter 2.2. --- Patch Modeling --- p.6 / Chapter 2.3. --- Freehand Sketch-based Modeling --- p.7 / Chapter 2.4. --- Template Based Modeling --- p.8 / Chapter 2.5. --- Curve Interpolation Method --- p.9 / Chapter 3. --- Surface Operations --- p.11 / Chapter 3.1. --- Surface Blending --- p.11 / Chapter 3.2. --- Surface Trimming --- p.13 / Chapter 3.3. --- Boolean Operations --- p.14 / Chapter 4. --- Subdivision Surface --- p.16 / Chapter 4.1. --- Basic Principle --- p.16 / Chapter 4.2. --- Catmull-Clark Surface --- p.17 / Chapter 5. --- Modeling Algorithm Overview --- p.21 / Chapter 6. --- Subdivision Surface Generation --- p.23 / Chapter 6.1. --- Input Curves --- p.23 / Chapter 6.2. --- Surface Sweeping --- p.24 / Chapter 6.3. --- Subdivision Surface Fitting --- p.29 / Chapter 7. --- Surface Blending --- p.32 / Chapter 7.1. --- Introduction --- p.32 / Chapter 7.2. --- Problem Definition --- p.32 / Chapter 7.3. --- Algorithm Overview --- p.36 / Chapter 7.4. --- Blend Region Detection --- p.39 / Chapter 7.4.1. --- Collision Detection --- p.40 / Chapter 7.4.2. --- Result and Analysis --- p.42 / Chapter 7.5. --- "Mesh Refinement, Surface Fitting and Region Removal" --- p.46 / Chapter 7.5.1. --- Mesh Refinement --- p.46 / Chapter 7.5.1.1. --- Adaptive Subdivision --- p.46 / Chapter 7.5.1.2. --- Additional Subdivision Constraint --- p.47 / Chapter 7.5.2. --- Surface Fitting --- p.49 / Chapter 7.5.2.1. --- General Approach --- p.49 / Chapter 7.5.2.2. --- Surface Point Correspondence --- p.50 / Chapter 7.5.2.3. --- Numerical Fitting Method --- p.51 / Chapter 7.5.3. --- Unwanted Region Removal --- p.55 / Chapter 7.5.4. --- Result and Analysis --- p.56 / Chapter 7.6. --- Boundary Smoothing --- p.58 / Chapter 7.6.1. --- General Approach --- p.59 / Chapter 7.6.2. --- Constraint on Deformation Direction of Vertex --- p.61 / Chapter 7.6.3. --- Result and Analysis --- p.63 / Chapter 7.7. --- Blend Curves --- p.65 / Chapter 7.7.1. --- Problem Definition --- p.65 / Chapter 7.7.2. --- Proposed Solution Overview --- p.66 / Chapter 7.7.3. --- Maintenance of Regular Vertex Valence along Blend Curve --- p.67 / Chapter 7.7.3.1. --- Pairing Up Blend Boundary Vertices --- p.70 / Chapter 7.7.4. --- Minimization of Distortion Caused by Extraordinary Vertices --- p.72 / Chapter 7.7.5. --- Blend Vertex Position Optimization Function --- p.74 / Chapter 7.7.5.1. --- Face Normal Expression --- p.74 / Chapter 7.7.5.2. --- Face Normal Difference Energy Function --- p.77 / Chapter 7.7.5.3. --- Midpoint Distance Energy Function --- p.78 / Chapter 7.7.5.4. --- Weighted Least Square Energy Minimization --- p.78 / Chapter 8. --- Implementation --- p.81 / Chapter 8.1. --- Data Structure --- p.81 / Chapter 8.2. --- User Interface --- p.82 / Chapter 9. --- Results --- p.83 / Chapter 9.1. --- Surface Generation --- p.83 / Chapter 9.2. --- Surface Blending --- p.86 / Chapter 9.2.1. --- Ideal Case --- p.86 / Chapter 9.2.2. --- Angle of Insertion --- p.87 / Chapter 9.2.3. --- Surface Feature Near Intersection --- p.88 / Chapter 9.2.4. --- Comparison --- p.89 / Chapter 9.2.5. --- Other Examples --- p.92 / Chapter 9.3. --- Overall Performance --- p.94 / Chapter 9.4. --- Limitations --- p.97 / Chapter 9.4.1. --- Limitation on Generated Shape --- p.97 / Chapter 9.4.2. --- Limitation on Input Surfaces --- p.98 / Chapter 10. --- Conclusion and Future Work --- p.99 / References --- p.100

Graduation date: 1998

Two methods of electro-optically characterizing alternating-current thin-film electroluminescent (ACTFEL) devices are investigated: photo-induced transferred charge (PIQ) and luminescence (PIL), and subthreshold voltage-induced transferred charge (VIQ) techniques. Both techniques provide information related to traps within the phosphor layer. PIQ/PIL experiments monitor the transport of electrons and holes across the phosphor layer which are photo-injected by a UV laser pulse. VIQ experiments monitor the optical reset of traps ionized by bipolar subthreshold voltage pulses. PIQ/PIL experiments are performed on three different SrS ACTFEL devices: ALE-deposited SrS:Ce, sputter-deposited SrS:Cu, and undoped MOCVD-deposited SrS. From the PIQ/PIL experiments, two distinct electron thresholds in the luminescent impurity doped samples at ~0.8 (weak threshold) and ~1.2 MV/cm (strong threshold) are observed. These thresholds are independent of the phosphor thickness, indicating that they arise from a bulk property of the phosphor. The ~0.8 MV/cm weak threshold is attributed to field emission of relatively shallow (~0.6 eV) electron-emitting bulk traps (e.g. cerium or oxygen for SrS:Ce; a sulfur vacancy or oxygen for SrS:Cu). The ~1.2 MV/cm strong threshold is ascribed to the onset of trap-to-band impact ionization. In contrast to electron transport, PIQ/PIL studies reveal no hole transport in SrS doped with luminescent impurities, although hole transport is observed for an undoped SrS ACTFEL device. The lack of hole transport is attributed to the efficiency of hole capture in SrS doped with luminescent impurities. VIQ experiments are performed on the same SrS ACTFEL devices. VIQ trap energy depths are estimated as ~0.1 eV for SrS:Ce; ~0.9 eV for SrS:Cu (with a capture cross-section of ,~10�������cm��), and ~0.6 eV for undoped SrS. Tenative atomic identification of traps responsible for these VIQ trends are: chlorine or a Ce shallow donor state for SrS:Ce, a sulfur vacancy for SrS:Cu, and a sulfur vacancy or an oxygen isoelectronic trap for undoped SrS. / Graduation date: 2000

Graduation date: 1997

Graduation date: 1996

Graduation date: 1998

Graduation date: 1995

Thesis (M.Sc.)--York University, 2008. Graduate Programme in Computer Science. / Typescript. Includes bibliographical references (leaves 95-101). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR38834

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Roberto Cristi, Fotis A. Papoulias. Includes bibliographical references (p. 155). Also available online.

No description available.