by Au Pat Nien. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 86-88). / Chapter 1 --- Introduction --- p.1 / Chapter 2 --- Valuations --- p.4 / Chapter 2.1 --- Preliminaries --- p.4 / Chapter 2.2 --- Complete Fields --- p.6 / Chapter 2.3 --- Unramified Extension of Complete Field --- p.10 / Chapter 2.4 --- Local Fields --- p.12 / Chapter 3 --- Ramification Groups and Hasse-Herbrand Function --- p.16 / Chapter 3.1 --- Ramification Groups --- p.16 / Chapter 3.2 --- "The Quotients Gi/Gi+1, i ≥ 0" --- p.17 / Chapter 3.3 --- The Hasse-Herbrand function --- p.19 / Chapter 4 --- The Norm Map --- p.21 / Chapter 4.1 --- Lemmas --- p.21 / Chapter 4.2 --- The Norm Map on the Residue Field of a Totally Ramified Extension of Prime Degree --- p.22 / Chapter 4.3 --- Extension of the Perfect Residue Field in a Totally Ramified Extension --- p.26 / Chapter 4.4 --- The Norm Map on Finite Separable Extension of Knr with K Perfect --- p.28 / Chapter 5 --- Cohomology of Finite Groups --- p.30 / Chapter 5.1 --- Preliminaries --- p.30 / Chapter 5.2 --- Mappings of Cohomology Groups --- p.32 / Chapter 5.2.1 --- Restriction and Inflation --- p.32 / Chapter 5.2.2 --- Corestriction --- p.34 / Chapter 5.3 --- Cup Product --- p.34 / Chapter 5.4 --- Cohomology Groups of Low Dimensions --- p.35 / Chapter 5.5 --- Some Results of Group Cohomology --- p.43 / Chapter 6 --- The Brauer Group of a Field --- p.57 / Chapter 7 --- The Norm Residue Map --- p.60 / Chapter 7.1 --- Determination of the Brauer Group of a Local Field --- p.60 / Chapter 7.2 --- Canonical Class --- p.62 / Chapter 7.3 --- The Reciprocity Law --- p.64 / Chapter 8 --- The Local Symbol --- p.74 / Chapter 8.1 --- Definition --- p.74 / Chapter 8.2 --- The Hilbert Symbol --- p.74 / Chapter 8.3 --- The Differential of the Formal Power Series --- p.76 / Chapter 8.4 --- The Artin-Schreier Symbol --- p.78 / Chapter 9 --- Characterization of a Norm Group --- p.81 / Bibliography

Luk Suet Ching (Weety). / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 100-114). / Questionaire also in Chinese. / ACKNOWLEDGMENTS --- p.i / ABSTRACT --- p.ii / TABLES OF CONTENTS --- p.iv / LIST OF TABLES --- p.vi / CHAPTER / Chapter 1. --- INTRODUCTION / Chapter 2. --- LITERATURE REVIEW --- p.6 / The definition and characteristics of distance education --- p.6 / Five groups of distance education programme --- p.8 / The advantages of distance education --- p.10 / The two characteristics of distance education --- p.10 / The flexibility in study of distance education --- p.13 / Adult education --- p.15 / The disadvantages of distance education --- p.16 / Dropout rates --- p.16 / The cognitive style --- p.21 / Field-dependent/field-independent cognitive style --- p.22 / The body adjustment test --- p.23 / The rod and frame test (RFT) --- p.23 / The Group Embedded Figures Test and Embedded Figures Test --- p.24 / Field-dependence/field-independence and academic achievement --- p.26 / The characteristics of field-dependence/field-independence --- p.26 / Cognitive style and academic achievement --- p.28 / Learning approaches associated with field- dependence/field-independence --- p.31 / Instructional package --- p.31 / non-contiguous communication --- p.32 / Learning approaches associated with adult students --- p.34 / Intrinsic factors --- p.35 / The acquirement of field-dependent/field-independent cognitive style --- p.35 / Extrinsic factors (interest to be self-directed) --- p.36 / Motivation --- p.36 / Commitment --- p.37 / Learning approach associated with Asian students --- p.38 / Conclusion --- p.39 / Chapter 3 --- RESEARCH METHODOLOGY / Research questions --- p.41 / Hypothesis --- p.42 / Population and sample --- p.44 / Instruments --- p.45 / Cognitive style --- p.45 / Academic achievement --- p.49 / Data collection procedures --- p.49 / GEFT --- p.49 / Academic achievement --- p.50 / Pilot study --- p.51 / Data analysis --- p.52 / Level of measurement --- p.53 / Sample size --- p.54 / Normal distribution --- p.55 / Ethical considerations --- p.57 / Chapter 4. --- RESULTS / The first hypothesis --- p.59 / The field-dependent cognitive style (GEFT) and the academic achievement scores --- p.60 / The second hypothesis --- p.65 / The field-dependent cognitive style (GEFT) and the academic achievement scores --- p.66 / The third hypothesis --- p.71 / The GEFT scores --- p.72 / The fourth hypothesis --- p.75 / Summary --- p.79 / Chapter 5. --- DISCUSSION / Relationship between academic achievement and field- independence --- p.83 / To change the impersonal learning environment of distance education --- p.86 / Level of field-dependent cognitive style in students over time --- p.87 / LIMITATIONS --- p.89 / IMPLICATIONS --- p.94 / RECOMMENDATIONS --- p.95 / The impersonal style of study --- p.95 / Instructional package --- p.96 / Supporting services --- p.96 / Study groups --- p.97 / CONCLUSION --- p.98 / REFERENCES --- p.100 / APPENDICES --- p.115 / Chapter I. --- The cover letter / Chapter II. --- The instructions for the GEFT

Fung Yun Ming. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 134-140). / Abstracts in English and Chinese. / Abstract --- p.I / Acknowledgement --- p.III / Contents --- p.IV / List of Figure captions --- p.VIII / List of Table captions --- p.XIII / Chapter Chapter 1 --- Introduction --- p.1 / Chapter Chapter 2 --- Theory and Applications / Chapter 2.1 --- Principle of field emission / Chapter 2.1.1 --- The Fowler-Nordheim Theory --- p.3 / Chapter 2.1.2 --- Field emission from metals --- p.6 / Chapter 2.1.3 --- Field emission from semiconductors --- p.8 / Chapter 2.1.3.1 --- Advantages and limitations of silicon --- p.9 / Chapter 2.1.4 --- Application of the Fowler-Nordheim theory --- p.10 / Chapter 2.1.5 --- Factors influencing field emission efficiency --- p.11 / Chapter 2.2 --- Applications --- p.11 / Chapter 2.2.1 --- Operation of a Field Emission Displays --- p.11 / Chapter 2.2.2 --- Basic structure of a Field Emission Displays --- p.13 / Chapter 2.2.3 --- Parameters relevant to applications --- p.15 / Chapter 2.3 --- The fabrication processes --- p.17 / Chapter 2.3.1 --- The anisotropic wet etching method --- p.18 / Chapter 2.3.2 --- The isotropic wet etching method --- p.19 / Chapter 2.3.3 --- Field emission from coating materials --- p.20 / Chapter 2.3.3.1 --- Coating enhancement --- p.20 / Chapter 2.3.3.2 --- Diamond and diamond-like films --- p.21 / Chapter 2.3.3.3 --- Metallic coatings --- p.22 / Chapter 2.3.3.4 --- Porous silicon coatings --- p.22 / Chapter 2.3.3.5 --- Silicon carbide coatings --- p.22 / Chapter 2.3.4 --- Fabrication of field emitters with gate --- p.23 / Chapter Chapter 3 --- Sample Preparation and Characterization Methods / Chapter 3.1 --- Sample preparation --- p.25 / Chapter 3.2 --- The fabrication process / Chapter 3.2.1 --- Isotropic etching of silicon / Chapter 3.2.1.1 --- The anodization process --- p.25 / Chapter 3.2.1.2 --- Porous silicon formation --- p.26 / Chapter 3.2.2 --- Anistropic etching of silicon --- p.27 / Chapter 3.2.3 --- The sputtering system --- p.28 / Chapter 3.2.4 --- The MEVVA Ion Source Implanter --- p.30 / Chapter 3.3 --- Characterization Methods / Chapter 3.3.1 --- Atomic Force Microscopy (AFM) --- p.32 / Chapter 3.3.2 --- Scanning Electron Microscopy (SEM) --- p.34 / Chapter 3.3.3 --- Field emission measurement / Chapter 3.3.3.1 --- Vacuum requirements --- p.35 / Chapter 3.3.3.2 --- Testing system / Chapter 3.3.3.3 --- Fluctuation of field emission --- p.38 / Chapter Chapter 4 --- Fabrication of Silicon Tips and their field emission charateristics / Chapter 4.1 --- The anodization etching process / Chapter 4.1.1 --- Introduction --- p.40 / Chapter 4.1.2 --- Experimental details --- p.42 / Chapter 4.1.3 --- Results and Discussions / Chapter 4.1.3.1 --- N type (100) sample --- p.45 / Chapter 4.1.3.2 --- Ntype(lll) sample --- p.60 / Chapter 4.1.3.3 --- Fluctuations of the emission current --- p.64 / Chapter 4.1.3.4 --- The effect of Concentration of HF solution on First Step Anodization --- p.68 / Chapter 4.1.3.5 --- The effect of the Concentration of HF solution on Second Step Anodization --- p.70 / Chapter 4.1.3.6 --- Gated silicon field emitter --- p.70 / Chapter 4.1.4 --- Conclusions --- p.73 / Chapter 4.2 --- Anisotropic texturing process / Chapter 4.2.1 --- Introduction --- p.74 / Chapter 4.2.2 --- Experimental details --- p.76 / Chapter 4.2.3 --- Results and Discussions --- p.78 / Chapter 4.2.4 --- Conclusion --- p.92 / Chapter 4.3 --- Formation of Porous Silicon Layer on silicon / Chapter 4.3.1 --- Introduction --- p.93 / Chapter 4.3.2 --- Experimental details --- p.94 / Chapter 4.3.3 --- Results and Discussions --- p.95 / Chapter 4.3.4 --- Conclusion --- p.100 / Chapter 4.4 --- Chapter Summary --- p.101 / Chapter Chapter 5 --- Improvement in the field emission characteristics of the silicon tips upon coating with low work function materials / Chapter 5.1 --- Amorphous carbon coating / Chapter 5.1.1 --- Introduction --- p.102 / Chapter 5.1.2 --- Experimental details --- p.103 / Chapter 5.1.3 --- Results and Discussions --- p.104 / Chapter 5.1.4 --- Conclusion --- p.118 / Chapter 5.2 --- Silicon carbide coated Silicon emitter by MEWA / Chapter 5.2.1 --- Introduction --- p.119 / Chapter 5.2.2 --- Experimental details --- p.120 / Chapter 5.2.3 --- Results and Discussions --- p.121 / Chapter 5.2.4 --- Conclusion --- p.125 / Chapter 5.3 --- Chapter Summary --- p.126 / Chapter Chapter 6 --- Conclusions --- p.127 / Reference --- p.134 / List of publications --- p.140

Since the seminal discovery of conductive polymers four decades ago, organic electronics has grown from an exploratory field to an industry offering novel consumer products. Research has led to the synthesis of new organic molecules and polymers and their applications: organic field-effect transistors (OFETs), organic light-emitting diodes, and organic photovoltaics. The goal for research as well as for industry is producing low-cost, flexible, and, ultimately, sustainable, electronics. Although on the rise, organic electronics faces several challenges: air instability, reliability, and scaling, to name a few. And despite that organic devices and larger systems have been demonstrated, there remains a gap in understanding underlying mechanisms behind light absorption, photoconduction, charge transport and conduction in them. The primary purpose of this thesis is to use a relatively under utilized technique, photocurrent microscopy (PCM), to directly probe charge carriers in pentacene and 6,13-Bis(triisopropylsilylethynyl) (TIPS) pentacene FETs to learn about charge injection and transport. The latter part of the thesis focuses on the use of thiols to modify electrode properties to both increase charge injection efficiency and to provide passivation to low-work function metal electrodes. It is demonstrated for the first time experimentally by directly probing the OFET channel that top-contact geometry OFETs suffer minimally from a charge injection barrier, and that trap filling and altering of trap density-of-states in the channel is directly observable with PCM. PCM was used to investigate grains and grain boundaries in TIPS-pentacene devices. By varying gate bias, it was shown that the PCM maps of grains are not simply a result of varying absorption on the surface of the film; rather, it is an artefact of charge transport between grains and grain boundaries. Through this study, PCM was shown to be a useful, large-area scanning technique, for observing transport in devices with large (on the order of 50 $\mu$m) grains. This is particularly relevant as solution-proccessable films are likely to dominate the flexible electronics industry. The thiol portion of this thesis compares the impact of two distinct thiols on bottom-contact pentacene FETs: perfluorodecanethiol (PFDT) and pentafluorobenzenethiol (PFBT). Using X-ray photoelectron spectroscopy to measure metal oxidation, it was determined that short aromatic thiols are poor choices for low work-function metal passivation. In addition, both passivation and charge injection enhancement can be achieved with long fluorinated alkanethiols. However, there is a trade-off between passivation and on-current. The enhancement of on-current in thiol-treated Cu-electrode pentacene devices is most likely not morphology related, due to the fact that PFDT was found to be in a standing-up orientation on the metal surface. Additionally, it was demonstrated that although highly electronegative atoms such as fluorine can beneficially modify metal work function, too many fluorine atoms in thiols can lead to too high a work function and a large mismatch between the pentacene highest-occupied-molecular-level and metal work function.

Orientador: Denis Dalmazi / Banca: Marcelo Hott / Banca: Nathan Jacob Berkovits / Resumo: Nesta disserta,ão obtemos modelos duais de rank superior para partículas de spin-0, spin-1 e spin-2 em D-dimensões utilizando a técnica da ação mestra. Como introdução obtemos um modelo simples para uma partícula de spin-0 utilizando um campo vetorial o qual servirá de paradigma para os capítulos posteriores. Verificamos o conteúdo físico obtido através de suas equações de movimento, propriedades analíticas do propagador e do algoritmo de Dirac-Bergman para sistemas vinculados. No caso de partículas de spin-1, fazemos um acoplamento mínimo na ação mestra tanto com o campo gravitacional quanto com o campo eletromagnético o que resulta, curiosamente, no aparecimento de termos não mínimos nas ações descendentes / Abstract: In this master thesis we obtain dual models of the higher rank type for particles of spin-0, spin-1 and spin-2 in D-dimensions by using the master action technique. As an introduction we obtain a simple model for a spin-0 particle by using a vectorial field which serve as paradigm for the next chapters. We verify the particle content of the models through the analysis of the equations of motion, analytical properties of the propagator and we count the degrees of freedom by using the Dirac-Bergman algorithm for constrained systems. In the case of spin-1 particles, we do a minimal coupling in the master action first with the gravitational field and secondly with the electromagnetic field which result, curiously, in the appearance of non minimal couplings terms in the descendent actions / Mestre

A confiabilidade do produto é um dos principais atributos da sua qualidade, porém a melhoria contínua desta confiabilidade é um objetivo inalcançável para as empresas, principalmente após o processo de globalização, no qual as empresas locais não têm como competidores apenas as empresas regionais ou nacionais, mas também as outras empresas mundiais. Outro fator importante, para o estabelecimento da confiabilidade, é o cliente que têm aumentado as suas exigências num processo contínuo, em que os aspectos de conformidade às especificações do projeto estão se tornando critério de compra. Este trabalho, através de um estudo de caso, apresenta a análise de um processo de atendimento a itens não conformes e propõe melhorias neste processo, visando agilizar a solução de problemas de campo. Para isso será avaliada a confiabilidade da empresa, desde a comunicação do cliente, passando pelo revendedor e da própria empresa, até a metodologia utilizada para a análise das falhas de campo dos produtos existentes. Os registros e informações da área de suporte e serviços, serão fundamentais para a introdução de melhorias para o procedimento atualmente em uso pela empresa. / The reliability of a product is one of the main attributes of its quality, however continuous improvement of its reliability is a never-ending journey for companies, especially those with global processes, as they must complete with other regional, national and global companies. Another important factor in determining the reliability of a product is the understanding of the critical customer requirements. Due to market globalization, consumers now have access to a greater variety of products and are better able to make comparisons between similar items. This ability drives consumers to constantly change or refine their critical requirements that ultimately influence their purchasing decisions. This case study presents an analysis of a process for monitoring product non-conformances and proposes process improvements aimed at speeding up the solution to field problems. To do this, company reliability will be analyzed in terms of the path of communication of product problems from the customer to the dealer, the dealer to the factory and from the factory to the methodology used to analyze field failures. Information from the product support and services area will be fundamental to the introduction of improvements to the current field failure processes.

Vast numbers of historical field recordings are currently being digitised and disseminated online; but what are these field recordings-and how do they resonate today? This thesis addresses these questions by listening to the digitisation of recordings made for a number of ethnographic projects that took place in Britain in the early 1950s. Each project shared a set of logics and practices I call national phonography. Recording technologies were invested with the ability to sound and salvage the nation, but this first involved deciding what the nation was, and what it was supposed to sound like. National phonography was an institutional and technological network; behind the encounter between recordist and recorded lies a complex and variegated mess of cultural politics, microphones, mediality, sonic aesthetics, energy policies, commercial interests, and music formats. The thesis is structured around a series of historical case studies. The first study traces the emergence of Britain's field recording moment, connecting it to the waning of empire, and focusing on sonic aspects of the 1951 Festival of Britain and the recording policies of national and international folk music organisations. The second study listens to the founding of a sound archive at the University of Edinburgh, also in 1951, asking how sound was used in constructing Scotland as an object of study, stockpiling the nation through the technologies and ideologies of preservation. The third study tracks how the BBC used fieldwork - particularly through its Folk Music and Dialect Recording Scheme (1952-57) - as part of an effort to secure the aural border. The fourth study tells the story of The Columbia World Library of Folk and Primitive Music, produced by Alan Lomax while based in Britain and released in 1955. Here, recordings were presented in fragments as nations were written onto long-playing records, and the project is discussed as a museum of voice. The final chapter shifts perspective to the online circulation of these field recordings. It asks what an online sound archive is, hearing how recordings compress multiple agencies which continue to unfold on playback, and exploring the archival silences built into sonic productions of nations. Finally, online archives are considered as heritage sites, raising questions about whose nation is produced by national phonography. This thesis brings together perspectives from sound studies and ethnomusicology; and contributes to conversations on the history of ethnomusicology in Europe, the politics of technology, ontologies of sound archives, and theories of recorded sound and musical nationalisms.

Yu, Xiaojiang. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2008. / Includes bibliographical references. / Abstracts in English and Chinese. / ABSTRACT (ENGLISH) --- p.I / ABSTRACT (CHINESE) --- p.III / ACKNOWLEDGEMENTS --- p.IV / TABLE OF CONTENTS --- p.V / Chapter 1. --- Overview of organic thin-film transistors (OTFTs) --- p.1 / Chapter 1.1 --- Introduction to OTFTs --- p.1 / Chapter 1.2 --- Basic mechanism of OTFTs --- p.4 / Chapter 1.3 --- Applications of OTFTs --- p.6 / Chapter 1.3.1 --- Driving of circuits for electronic papers and LCD --- p.6 / Chapter 1.3.2 --- Light-emitting OTFTs --- p.8 / Chapter 1.3.3 --- Sensing --- p.9 / Chapter 1.4 --- Several key issues --- p.9 / Chapter 1.4.1 --- Mobilities of OTFTs --- p.9 / Chapter 1.4.2 --- Performance of bottom-contact OTFTs --- p.10 / Chapter 1.4.3 --- Stability of OTFTs --- p.11 / Chapter 1.4.4 --- Performance of n-type organic semiconductors --- p.13 / Chapter 1.5 --- Why to study metallophthalocyanine-based OTFTs --- p.14 / Chapter 1.6 --- Objective of this thesis --- p.17 / References --- p.17 / Chapter 2. --- Experimental details for fabrication and characterization of OTFTs --- p.22 / Chapter 2.1 --- Purification of organic semiconductors --- p.22 / Chapter 2.2 --- Preparation of the gate dielectrics for OTFTs --- p.24 / Chapter 2.3 --- Deposition of organic thin films and gold source/drain electrodes --- p.26 / Chapter 2.4 --- Process flow for the fabrication of OTFTs --- p.27 / Chapter 2.5 --- Mobility measurement for the organic thin films --- p.28 / Chapter 2.6 --- Characterization of organic thin films --- p.31 / References --- p.31 / Chapter 3. --- Optimizing the growth of VOPc thin films for high-mobility OTFTs --- p.33 / Chapter 3.1 --- Experimental --- p.33 / Chapter 3.2 --- Results and discussion --- p.34 / Chapter 3.2.1 --- Growth of VOPc thin films on Si02 dielectric --- p.34 / Chapter 3.2.2 --- Growth of VOPc thin films on Ta205 and Al203/Si02 dielectrics --- p.41 / Chapter 3.4 --- Conclusion --- p.44 / References --- p.45 / Chapter 4. --- CuPc/CoPc and VOPc/CoPc p-type/p-type heterostructure OTFTs --- p.46 / Chapter 4.1 --- CuPc/CoPc OTFTs in sandwich configuration --- p.47 / Chapter 4.1.1 --- Experimental --- p.47 / Chapter 4.1.2 --- Results and discussion --- p.48 / Chapter 4.1.3 --- Conclusion --- p.57 / Chapter 4.2 --- VOPc/CoPc OTFTs --- p.57 / Chapter 4.2.1 --- Experimental --- p.57 / Chapter 4.2.2 --- Results and discussion --- p.58 / Chapter 4.2.3 --- Conclusion --- p.63 / References --- p.64 / Chapter 5. --- VOPc/F16CuPc p-type/n-type heterostructure OTFTs --- p.66 / Chapter 5.1 --- Unipolar VOPc/F16CuPc OTFTs --- p.67 / Chapter 5.1.1 --- Experimental --- p.67 / Chapter 5.1.2 --- Results and discussion --- p.69 / Chapter 5.1.3 --- Conclusion --- p.73 / Chapter 5.2 --- VOPc/F16CuPc heterostructure for bottom-contact OTFTs --- p.74 / Chapter 5.2.1 --- Experimental --- p.74 / Chapter 5.2.2 --- Results and discussion --- p.74 / Chapter 5.2.3 --- Conclusion --- p.77 / References --- p.77 / Chapter 6. --- Summary and future work --- p.80 / Summary --- p.80 / Future work --- p.81 / References --- p.83 / Appendix A: Capacitance-voltage (C-V) fitting for ITO/organic junction/AI devices --- p.85 / Appendix B: Can electric-filed influence the growth of organic thin films? --- p.89 / Appendix C: Micro-Raman study on organic thin films --- p.93 / Appendix D: Publications which contributed to this thesis --- p.97

Typescript. / Digitized by Kansas Correctional Industries

Typescript. / Digitized by Kansas Correctional Industries