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Chung, Wai Fung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 98-100). / Abstracts in English and Chinese. / 摘要 --- p.III / ACKNOWLEDGEMENT --- p.IV / CONTENTS --- p.V / LIST OF FIGURES --- p.VIII / LIST OF TABLES --- p.X / LIST OF TABLES --- p.X / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Motivation --- p.1 / Chapter 1.2 --- Receiver Architecture --- p.3 / Chapter 1.2.1 --- Zero-IF Receivers --- p.4 / Chapter 1.2.2 --- Low-IF Receivers --- p.6 / Chapter 1.2.2.1 --- Hartley Architecture --- p.7 / Chapter 1.2.2.2 --- Weaver Architecture --- p.9 / Chapter 1.3 --- Image-rejection ratio --- p.10 / Chapter 1.4 --- Thesis Organization --- p.12 / Chapter CHAPTER 2 --- FUNDAMENTALS OF OSCILLATOR --- p.13 / Chapter 2.1 --- Basic Oscillator Theory --- p.13 / Chapter 2.2 --- Varactor --- p.15 / Chapter 2.3 --- Inductor --- p.17 / Chapter 2.4 --- Phase noise --- p.22 / Chapter 2.4.1 --- The Leeson ´ةs phase noise expression --- p.24 / Chapter 2.4.2 --- Linear model --- p.25 / Chapter 2.4.3 --- Linear Time-Variant phase noise model --- p.28 / Chapter CHAPTER 3 --- FULLY-INTEGRATED CMOS OSCILLATOR DESIGN --- p.31 / Chapter 3.1 --- Ring oscillator --- p.31 / Chapter 3.2 --- LC oscillator --- p.33 / Chapter 3.2.1 --- LC-tank resonator --- p.34 / Chapter 3.2.2 --- Negative transconductance --- p.36 / Chapter 3.3 --- Generation of quadrature phase signals --- p.39 / Chapter 3.4 --- Quadrature VCO topologies --- p.41 / Chapter 3.4.1 --- Parallel-coupled QVCO --- p.41 / Chapter 3.4.2 --- Series-coupled QVCO --- p.46 / Chapter 3.4.3 --- QVCO with Back-gate Coupling --- p.47 / Chapter 3.4.4 --- QVCO using superharmonic coupling --- p.49 / Chapter 3.5 --- Novel QVCO using back-gate superharmonic coupling --- p.52 / Chapter 3.5.1 --- Tuning range --- p.54 / Chapter 3.5.2 --- Negative gm --- p.55 / Chapter 3.5.3 --- Phase noise calculation --- p.56 / Chapter 3.5.4 --- Coupling coefficient --- p.57 / Chapter 3.5.5 --- Low-voltage and low-power design --- p.59 / Chapter 3.5.6 --- Layout Consideration --- p.61 / Chapter 3.5.6.1 --- Symmetrical Layout and parasitics --- p.61 / Chapter 3.5.6.2 --- Metal width and number of vias --- p.63 / Chapter 3.5.6.3 --- Substrate contact and guard ring --- p.63 / Chapter 3.5.7 --- Simulation Results --- p.65 / Chapter 3.5.7.1 --- Frequency and output power --- p.65 / Chapter 3.5.7.2 --- Quadrature signal generation --- p.67 / Chapter 3.5.7.3 --- Tuning range --- p.67 / Chapter 3.5.7.4 --- Power consumption --- p.68 / Chapter 3.5.7.5 --- Phase noise --- p.69 / Chapter 3.6 --- Polyphase filter and Single-sideband mixer design --- p.70 / Chapter 3.6.1 --- Polyphase filter --- p.72 / Chapter 3.6.2 --- Layout Consideration --- p.74 / Chapter 3.6.3 --- Simulation results --- p.76 / Chapter 3.7 --- Comparison with parallel-coupled QVCO --- p.78 / Chapter CHAPTER 4 --- EXPERIMENTAL RESULTS --- p.80 / Chapter 4.1 --- Test Fixture --- p.82 / Chapter 4.2 --- Measurement set-up --- p.84 / Chapter 4.3 --- Measurement results --- p.86 / Chapter 4.3.1 --- Proposed QVCO using back-gate superharmonic coupling --- p.86 / Chapter 4.3.1.1 --- Output Spectrum --- p.86 / Chapter 4.3.1.2 --- Tuning range --- p.87 / Chapter 4.3.1.3 --- Phase noise --- p.88 / Chapter 4.3.1.4 --- Power consumption --- p.88 / Chapter 4.3.1.5 --- Image-rejection ratio --- p.89 / Chapter 4.3.2 --- Parallel-coupled QVCO --- p.90 / Chapter 4.3.2.1 --- Output spectrum --- p.90 / Chapter 4.3.2.2 --- Power consumption --- p.90 / Chapter 4.3.2.3 --- Tuning range --- p.91 / Chapter 4.3.2.4 --- Phase noise --- p.92 / Chapter 4.3.3 --- Comparison between proposed and parallel-coupled QVCO --- p.93 / Chapter CHAPTER 5 --- CONCLUSIONS --- p.95 / Chapter 5.1 --- Conclusions --- p.95 / Chapter 5.2 --- Future work --- p.97 / REFERENCES --- p.98

The aim of this research was to formulate, characterise and assess the feasibility of a novel drug delivery system known as the in situ gelling matrix (ISGM) where a hydrophilic polymer is suspended in a non-aqueous solvent that converts into a gel when injected subcutaneously or intramuscularly thus giving a controlled release matrix for a drug. Although the concept has been patented with claims that this kind of drug delivery is achievable in theory for a wide variety of candidate substances, actual formulation studies for making a commercially viable product for this technology are completely lacking in practice. The research embodied in this thesis addresses this lack. Initial studies involved conducting a biocompatibility study using the HET-CAM (hens egg test - chorioallantoic membrane) test on a range of possible ingredients for the delivery system. The materials deemed biocompatible were then carried through to a screening process where the physical stability of the hydrophilic polymers in non-aqueous solvents was monitored. It was found that the hydrophilic polymers tested sedimented rapidly in the non-aqueous solvents indicating such a system was not physically stable. Consequently, density-inducing or viscosity-inducing agents were added to the non-aqueous solvents to retard the sedimentation rate. The addition of polycarbophil, a viscosity-inducing agent, clearly increased the viscosity of the system. However, undesirable formation of polycarbophil globules occurred during the manufacturing process, which caused batch-to-batch variations in the viscosity of the continuous phase. Various manufacturing methods were tested before arriving at the optimum procedure to prevent globule formation using a high speed dispersion tool. A final physical sedimentation analysis of candidate continuous phases and hydrophilic polymers was conducted for determining the ideal combination of ingredients to use in the system. These investigations finally led to the adoption of an optimum mix of components consisting of 10% (w/w) hydroxypropyl methylcellulose (HPMC) (the hydrophilic polymer) suspended in a continuous phase of propylene glycol (the non-aqueous solvent) containing 0.67% (w/w) polycarbophil (the viscosity inducing agent). Using this mix of components, the in situ gelling matrix system was then subjected to various characterisation studies including infrared (IR), differential scanning calorimetry (DSC), ultraviolet-visible (UV-Vis) spectrophotometry and redispersion studies. The chemical stability of the hydrophilic polymer and the continuous phase (the non-aqueous solvent and polycarbophil) was monitored and were found to be chemically stable over a 9 month period. The feasibility of the in situ gelling matrix technology as a controlled release device was assessed using the drug propranolol. In vitro drug release studies were conducted using a custom-built dissolution apparatus. The effect of various parameters such as the concentration of the hydrophilic gelling agent on the drug release rate was investigated. Increasing the concentration of the gelling agent in the formulation resulted in a slower rate of release. The drug release data were modelled using the Higuchi relationship and a power law relationship to compare the effects of the various parameters on the release rate Stability studies on the drug in the in situ gelling matrix system were carried out by storing samples in accelerated ageing conditions of 40 C / 75% relative humidity for 4 weeks. During this time, the samples were analysed each week by high performance liquid chromatography (HPLC). These demonstrated that no apparent drug degradation had occurred over the 4-week period. This indicates that the drug propranolol in the in situ gelling matrix system is stable under ambient conditions for at least 4 weeks. The results of this study demonstrated that the in situ gelling matrix technology is potentially viable as a drug delivery system and provide a practical methodology for the commercial development of such systems.

Thesis (M.S. in electrical engineering)--Washington State University, December 2007. / Includes bibliographical references (p. 55-56).

Graduation date: 1995

Thesis (Ph. D.)--University of Washington, 1983. / Vita. Bibliography: leaves [202]-216.

Controlled radical polymerization has proven to be a viableroute to obtain polymers with narrow polydispersities (PDI's)and controlled molecular weights under simple reactionconditions. It also offers control over the chain-]ends of thesynthesized polymer. Atom transfer radical polymerization(ATRP) is the most studied and utilized of these techniques. Inthis study ATRP has been utilized as a tool to obtain differentcomplex macromolecular structures. In order to elaborate a system for which a multitude ofchains can polymerize in a controlled manner and in closeproximity to one another, a multifunctional initiator based onpoly(3-ethyl-3-(hydroxymethyl)oxetane was synthesized. Themacroinitiator was used to initiate ATRP of methyl acrylate(MA). The resulting dendritic-]linear copolymer hybrids hadcontrolled molecular weights and low PDI's. Essentially thesame system was used for the grafting of MA from a solidsubstrate, cellulose. A filter paper was used as cellulosesubstrate and the hydroxyl groups on the cellulose weremodified into bromo-]ester groups, known to initiate ATRP.Subsequent grafting of MA by ATRP on the cellulose made thesurface hydrophobic. The amount of polymer that was attached tothe cellulose could be tailored. In order to control that thesurface polymerization was -eliving-f and hence that thechain-]end functionality was intact, a second layer of ahydrophilic monomer, 2-hydroxyethyl methacrylate, was graftedonto the PMA- grafted cellulose. This dramatically changed thehydrophilicity of the cellulose. Dendronized polymers of generation one, two and three weresynthesized by ATRP of acrylic macromonomers based on2,2-bis(hydroxymethyl)propionic acid. In the macromonomerroute, macromonomers of each generation were polymerized byATRP. The polymerizations resulted in polymers with low PDI's.The kinetics of the reactions were investigated, and thepolymerizations followed first-order kinetics when ethyl2-bromopropionate was used as the initiator. In the-egraft-]onto-f route dendrons were divergently attached to adendronized polymer of generation one, that had been obtainedby ATRP.

Gastrointestinal (GI) transit data were collected using pigs as animal models. Density and size effects of non-disintegrating dosage forms on GI transit were investigated. Total GI transit times range from 2 to 33 days for 22 administrations of these nondisintegrating dosage forms. Pigs are found to not be an appropriate animal model for studying bioavailability or GI transit of non-disintegrating, non-erodible oral release dosage forms. Development of controlled release dosage forms where the mechanism of drug release is diffusion through polymeric membrane formed via film coating utilizing fluid-bed technology requires optimization of several processing and formulation variables. The influence of a processing variable (nozzle orifice opening) and a few formulation variables (individual vs. combination plasticizer, or a water-insoluble additive) on dissolution of a model drug (acetaminophen) spray coated with Aquacoat® were studied. Pharmacodynamic and pharmacokinetic information for a model drug (acetaminophen) and computer simulation were used to develop a dosage form with a 12 hour sustained release for oral administration to children and adults for maximum analgesic and antipyretic effect. Simulated plasma acetaminophen concentration-time curves were similar to observed bioavailability study profiles. In vitro and preliminary in vivo results from an adult human volunteer indicate that sustained therapeutic saliva acetaminophen concentration is possible using the newly developed acetaminophen molded tablet dosage form. The bioavailability of the new, oral controlled release acetaminophen molded tablet relative to a commercially available product (Extra-Strength Tylenol® caplet) was evaluated in 8 healthy, adult volunteers. Multiple doses of these two products were administered in a two-way cross-over design. Bioavailability of the new sustained release molded tablet is comparable to that of the immediate release product. Polymer coated acetaminophen beads were effective in maintaining saliva acetaminophen concentrations of 5 μ/ml over a 12 hour dosing interval. / Graduation date: 1991

Remote-controlled-vehicle Control System is a control system applied between the controller and remote-controlled-vehicle. For casual life is prevailing over recent years, old control systems should be replaced. The goal of this study is introducing a set of design methodology to design Remote-controlled-vehicle Control Systems by applying engineering design methods. At the first, we explored in the Remote-controlled-vehicle Control Systems. In order to clarify the design task, ¡§Objectives Tree¡¨ was applied to clarify six design tasks of need, and to establish the charts of seven design specification of Remote-controlled-vehicle Control Systems. In the concept design stage, we used the ¡§Function Analysis Method¡¨ to analysis and synthesis the function structure of the Remote-controlled-vehicle Control Systems, and we created two types of function structure, and found many working solutions of our concept by applying Creative Techniques. In the following embodiment design stage, we used ¡§Morphological Chart Method¡¨ to find 90 working solutions for type I, 90 solutions for type II, and finally evaluated and selected better ones by processing of ¡§Evaluation Chart¡¨ thrice. We evaluated the solutions of type I and type II, thus we got 22 solutions for each type, and in following, we evaluated all ones totally, got nine solutions in the second time, and got seven better and potential concepts of design in the third time, and drew the diagrams of real object. The result of this study can benefit the creative design and development of Remote-controlled-vehicle Control Systems.