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Poly(dimethylsiloxane) (PDMS), is one of the polymers with the lowest surface energy in common use, it possesses good physical and electrical properties, which, along with easy processability makes it suitable for use in a range of different industrial and domestic applications. In this study, the surfaces of two PDMS formulations have been treated with a mild, low pressure, plasma to modify the surface properties. The, normally non-adhesive, PDMS was found to adhere very well to glass substrates after plasma treatment. This study has been carried out to gain a better understanding of the physico-chemical reactions and changes that take place on the surface of plasma treated PDMS by using XPS, ToF-SIMS and AFM to characterise the PDMS surfaces. During this work, a novel approach was successfully developed using an artificial neural network to sort and classify the large number of very similar XPS spectra that resulted from the investigation of plasma treated PDMS. Peak fitting protocols have been devised for complex Cls and Si2p XPS spectra of the model and commercial PDMS, and these results correlate well with the formation of an SiOH component, identified by ToF-SIMS. The SiOH component is the main factor responsible for adhesion between plasma treated PDMS and glass. The level of adhesion achieved between the plasma treated PDMS and glass has been quantified using a modified JKR approach developed for this work, and is shown to be related to the plasma exposure time. The characterisation of the PDMS surfaces, before and after plasma treatment, has led to an understanding of the mechanism of plasma surface modifications and subsequent mechanisms of adhesion between PDMS and glass. Models for such mechanisms are proposed on the basis of spectroscopic and empirical observations.

Never before in human history have so many people lived to be old. Korea like many countries has been experiencing the rapid growth of its elderly population. However in Korea, little research has been undertaken in regard to this group. This thesis aims at contributing to a better knowledge of the elderly in Korea, especially of their quality of life. The thesis examines the relationships between the quality of life determinants and life satisfaction amongst the Korean elderly with special reference to activities. Quality of life determinants include socio-economic status, health, environment, and cultural value which serve as independent variables. Activity, an intervening variable, is disaggregated into three types: group, informal, and leisure. Life satisfaction is conceptualised as a global sense of subjective well-being which does not represent any specific life concern. The field research for the study was carried out in four different areas of Seoul, Korea, selected on the basis of their contrasting residential land value. Data was collected from four different but complementary sources: archival records, 285 representative interviews using a structured questionnaire, 30 in-depth interviews with a sample of individuals over 60 years old, and 4 in-depth interviews with social workers. In this research greater participation in leisure activities amongst the Korean elderly was found to be positively correlated with their increased life satisfaction. The descending order of variables which have relatively significant influence on leisure activities and life satisfaction is cultural value, economic status, health, and environment. However, sociodemographic variables such as age, gender and educational level do not have any significant impact.

E.P. Sanders in his work, Jesus and Judaism, advances a refreshingly new position concerning Jesus' teaching on forgiveness. This dissertation is focused on pointing out why some of Sanders' arguments remain unconvincing and at advancing more convincing theses against his case in the light of a close examination of relevant passages in the synoptic gospels. Chapter 1 consists of several parts: a short introduction on Sanders' academic career, his significant contributions, overall review of Jesus and Judaism, and a critical examination of his five main arguments concerning Jesus' teaching on forgiveness. (1) Jesus does not ask for national repentance. (2) Jesus does not stress the need for repentance. (3) Jesus does not make repentance according to the law which requires restitution and/or sacrifice a condition for joining his band of disciples. (4) The only requirement was to 'follow' him, i.e., to join his band and 'accept' his message. (5) Jesus does not give his message on forgiveness an eschatological thrust like John the Baptist. Chapter 2 comprises a close examination of five passages appearing in three synoptic gospels, which turn out to be authentic sayings of Jesus. Jesus proclaims national repentance: Mark 1:15; Matt 4:17; Mark 8:12; Matt 12:39; Luke 11:29; Matt 12:42-42; Luke 11:31-32. Jesus teaches the need of making restitution to God: Mark 1:40-44; Matt 8:2-4; Luke 5:12-16. Chapter 3 contains investigations of the authenticity of seven passages which appear in Matthew and Luke but not in Mark. Matt 6:12; Luke 11:4; Matt 10:5-15; Luke 10:2-12; Matt 11:16-19; Luke 7:31-35; Matt 23:37-39; Luke 13:34-35; Matt 11:21-23; Luke 10:13-15 attest that Jesus and his disciplines call for national repentance with an eschatological overtone. Matt 5:25-26; Luke 12:57-59; Matt 6:12; Luke 11:4; Matt 18:12-14; Luke 15:4-7 elucidate Jesus' stress on repentance, restitution, reconciliation along with forgiveness.

The present study focuses on developing an efficient and stable unmanned aerial system traffic management (UTM) system that utilizes a data-driven target tracking method and a distributed path planning algorithm for multiple Unmanned Aerial Vehicle (UAV) operations with local dynamic networks, which can provide flexible scalability, enabling autonomous operation of a large number of UAVs in dynamically changing environment. Traditional dynamic motion-based target tracking methods often encounter limitations due to their reliance on a finite number of dynamic motion models. To address this, data-driven target tracking methods were developed based on the statistical model of the Gaussian mixture model (GMM) and deep neural networks of long-short term memory (LSTM) model, to estimate instant and future states of UAV for local path planning problems. The estimation accuracy of the data-driven target tracking methods were analyzed and compared with dynamic model-based target tracking methods. A hybrid dynamic path planning algorithm was proposed, which selectively employs grid-free and -based path search methods depending on the spatio-temporal characteristics of the environments. In static environment, the artificial potential field (APF) method was utilized, while the $A^*$ algorithm was applied in the dynamic state environment. Furthermore, the data-driven target tracking method was integrated with the hybrid path planning algorithm to enhance deconfliction. To ensure smooth trajectories, a minimum snap trajectory method was applied to the planned paths, enabling controller tracking that remains dynamically feasible throughout the entire operation of UAVs. The methods were validated in the Software-in-the-loop (SITL) demonstration with the simple PID controller of the UAVs implemented in the software program.

The first chapter, co-authored with Younghun Shim, studies how the adoption of foreign technology and local spillovers from such adoption contributed to late industrialization in a developing country during the postwar period. Using novel historical firm-level data for South Korea, we provide causal evidence of direct productivity gains to adopters and local productivity spillovers of the adoption. Based on these empirical findings, we develop a dynamic spatial model with firms' technology adoption decisions and local spillovers. The spillovers induce dynamic complementarity in firms' technology adoption decisions. Because of this dynamic complementarity, the model potentially features multiple steady states. Temporary adoption subsidies can have permanent effects by moving an economy to a new transition path that converges to a higher-productivity steady state. We calibrate our model to the microdata and econometric estimates. We evaluate the effects of the South Korean government policy that temporarily provided adoption subsidies to heavy manufacturing firms in the 1970s. Had no adoption subsidies been provided, South Korea would have converged to a less industrialized steady state in which the heavy manufacturing sector’s share of GDP would have been 15 percentage points lower and aggregate welfare would have been 10% lower compared to the steady state with successful industrialization. Thus, temporary subsidies for technology adoption had permanent effects. The second chapter, co-authored with Andrei Levchenko, provides causal evidence on the impact of industrial policy on firms' long-term performance and quantifies industrial policy's long-term welfare effects. Using a natural experiment and unique historical data during the Heavy and Chemical Industry (HCI) Drive in South Korea, we find large and persistent effects of firm-level subsidies on firm size. Subsidized firms are larger than those never subsidized even 30 years after subsidies ended. Motivated by this empirical finding, we build a quantitative heterogeneous firm model that rationalizes these persistent effects through a combination of learning-by-doing (LBD) and financial frictions that hinder firms from internalizing LBD. The model is calibrated to firm-level micro data, and its key parameters are disciplined with the econometric estimates. Counterfactual analysis implies that the industrial policy generated larger benefits than costs. If the industrial policy had not been implemented, South Korea's welfare would have been 21-35% lower, depending on how long-lived are the productivity benefits of LBD. Between 80 and 90% of the total welfare difference comes from the long-term effects of the policy. The third chapter studies the impact of lobbying on resource misallocation and aggregate TFP. I develop a model of heterogeneous firms that can lobby to decrease their output tax/distortion. This lobbying effort can either magnify or mitigate a pre-lobbying level of misallocation depending on whether the more productive firms are initially more distorted. If the more productive firms are burdened by higher pre-lobbying exogenous distortions, they can lobby to overcome these distortions, which increases aggregate total factor productivity (TFP). The TFP influences of lobbying can be affected by international trade as exporters increase their lobbying expenditures due to complementarities between market size and gains from a lower tax post-lobbying. I estimate the model by reduced-form instrumental variables techniques and structurally using firm-level data. I find that lobbying can increase US TFP by 4-7% compared to a counterfactual economy with the same pattern of pre-lobbying distortions, but where lobbying is not allowed.

This dissertation studies the dynamics of exchange rates and their effect on nominal and real macro variables and furthermore on policy choices. The dissertation provides a theoretical framework where a policymaker can choose a path of international policy portfolio of capital controls and exchange rate regimes under financial frictions. The paper presents a novel theoretical approach to explain the coexistence of active use of capital controls and volatile exchange rates, which has become a robust feature in emerging market economies. Building upon the small open economy framework, I create an environment where the policymaker can decide the level of exchange rate regimes -- instead of a binary choice of exchange rate regime, fixed or floating -- in response to external shocks, where capital controls are introduced as a tax on international capital flows. I further assume that regime choice is subject to a financial friction; breaking the peg signals the country's economic instability, which raises the country's risk premium. Under this set-up, the floating exchange rate regime does not welfare-dominate the capital controls any longer because loosening/losing the controls over exchange rates may expose households to additional risk premium. The simulation results show that the coexistence of managed float and capital controls becomes optimal. Furthermore, this additional friction has a multiplying effect, which makes exchange rate stabilization become important to prevent a bigger welfare loss. It also captures that optimal capital controls indirectly manage exchange rate depreciation, which allow policymakers to put less resource to stabilize the exchange rates. Considering the fact that the countries actively intervene in the foreign exchange market, the dissertation re-investigates one of classical puzzles in international economics using a new estimation technique and a modern data categorization methodology. The Purchasing Power Parity puzzle states that even though real exchange rates may converge to parity in the long run, the consensus emerging from an extensive literature appears to be that the rate of mean-reversion is slow, where a half-life mean-reversion is between 3 - 5 years; however, this is much too long to be compatible with arbitrage. This paper first proposes that investigating the periods of de facto floating regime will explain seemingly unrealistic persistence in real exchange rates by presenting lower persistence in real exchange rates than the estimates of previous studies, which include the periods de facto fixed regime in their data set by using de jure regimes. Secondly, previous studies have included the periods when real exchange rates that are within ``the regions of inaction''; because the trend of mean-reversion rates is non-linear, including the periods when real exchange rates are already converged to their means will bias the estimates toward zero, which are translated to the slow mean-reversion in real exchange rate estimates. Therefore, unbiased mean-reversion estimates can be estimated if I investigate the periods when the sample countries are under de facto float regimes and the periods when real exchange rates are statistically far from their means. Studying the data of nineteen goods CPI for eleven countries confirms these propositions. The mean group estimation decreases the half-life by 28.26% (half-life of 23.14 months) compared to fixed-effects estimation. The exchange rates regime dummy decreases the half-life estimate to 19.81 months and the region of inaction dummy decreases the estimates to 15.22 - 20.54 months. Using both dummy variables elicits the results that make the puzzle less puzzling; the half-life estimates are 9.30 - 13.89 months.The dissertation also explores the exchange rate regime-elastic risk premium quantitatively. This paper takes foreign investor's perspective and studies how the trend of risk premium changes when the regime switches in ten emerging market economies through the event study framework. Using a daily data set, the events of de facto regime switching are identified following the comparable methodology used in Calvo and Reinhart (2002), and EMBI+ is used as a proxy for country risk. The results confirm that switching exchange rate regimes from fixed to floating incurs an abrupt increase in average risk premium. EMBI+ rises by 141.11 - 165.48 basis points (0.257 - 0.525 standard deviations) around the events and shows 205.72 - 340.30 basis points of 40-day average difference before and after the events. The abnormal return estimates during the events range from 0.0036 to 0.0075, which imply 8.31 - 225.85% increase in the returns of EMBI+ during the periods of breaking pegs.

In Drosophila, studies of reproductive protein evolution have shown evidence of elevated levels of adaptive evolution compared to the genomic background. Few, however, have studied the molecular evolution of genes involved in the regulation of the germline stem cell (GSC). My dissertation examines the population genetics of a larger class of genes regulating the GSC, and using a comparative genomic approach to test the hypothesis that infection by the endosymbiotic bacteria Wolbachia pipientis is a selective driver causing the rapid evolution at some of the GSC genes. First, following up on previous observations of adaptive evolution of several GSC genes (particularly bam and bgcn) in D. melanogaster and D. simulans, I have studied the population genetics of these genes in D. ananassae because this species also shows evidence of infection by W. pipientis. However, despite what I show to be a comparable W. pipientis infectious history among D. melanogaster, D. simulans, and D. ananassae; neither bam nor bgcn were evolving under positive selection in D. ananassae. Thus, a simple W. pipientis driven rapid evolution at these genes was not supported by my results. Second, I expanded the population genetic analysis of GSC genes to include all genes that show evidence of involvement in D. melanogaster GSC regulation. Results for these were then compared to genes involved in neural stem cell regulation. My results showed that both germline and neural stem cell are enriched for genes with evidence of recent selective sweeps, but not long-term recurrent adaptive evolution, compared to a randomly chosen group of control genes. Further, overall inferences of rates of adaptive fixation for germline and neural stem cells showed levels comparable to most classes of genes for D. melanogaster and D. simulans. Lastly, I have used whole-genome sequencing to gain deeper insight into the evolutionary history of W. pipientis infecting D. ananassae. D. ananassae has unique evidence of the whole genome of W. pipientis integrated into the host nuclear genome. My results showed that the infectious W. pipientis genome has a stable maternally inherited evolutionary history while the integrated W. pipientis genome had become a potentially functionless pseudogenome.

Electrophoretic deposition (EPD) is a method to deposit particles dispersed in a liquid onto a substrate under the force of an applied electric field, and has been applied for depositing phosphors for application in solid state lighting. The objective is to deposit phosphors in a "remote phosphor" configuration for a UV-LED-based light source for improved white light extraction efficiency. It is demonstrated that EPD can be used to deposit red-, green-, blue-, yellow- and orange-emitting phosphors to generate white light using a near UV-emitting LED by either depositing a phosphor blend or sequentially individual phosphor compositions. The phosphor coverage was excellent, demonstrating that EPD is a viable method to produce phosphor layers for the "remote phosphor" white light design. The deposition rates of the individual phosphor films were ̃1-5 [mu]m/min. The blend depositions composed of both three and four phosphor compositions emit white light located on or near the black body locus on the CIE chromaticity diagram. Phosphor films were also prepared by sequential deposition of red/orange and green/ blue compositions, to generate white light. The layered films were flipped over and illuminated in this orientation, which showed approximately the same luminescence characteristics. No change in the reabsorption ratio of green/blue emission by the red/ orange phosphor was found regardless of the deposited order of the layered films. These applications of EPD of phosphor for white solid state lighting are promising and effective due to easy tuning of emissive color by varying the phosphor blend compositions. Although nanoparticles of a variety of materials have been coated by EPD, there have been few direct comparisons of EPD of nano- and micron- sized particles of the same material. Another field of the study was to compare EPD of nano-, nano core/SiO₂ shell and micron-sized (Ba₀.₉₇Eu₀.₀₃)₂SiO₄ phosphor particles for application in a near-UV LED-based light source. EPD from an amyl alcohol bath was able to produce uniform films for all particle sizes, whereas uniform films were produced only of micron-sized particles in an isopropyl alcohol bath. A new equation was developed for predicting the deposited mass, considering the change in concentration of particles in the bath from both settling and deposition, showed good agreement with the experimental values

Vacuum technology is ubiquitous in the high tech industries and scientific endeavors. Since vacuum pumps are critical to operation, semiconductor manufacturers desire reliable operations, ability to schedule downtime, and less costly maintenance services. To better cope with difficult maintenance issues, interests in novel fault diagnosis techniques are growing. This study concerns model based fault diagnosis and isolation (MB-FDI) of dry vacuum pumps in the semiconductor industry. Faults alter normal operation of a vacuum pump resulting in performance deviations, discovered by measurements. Simulations using an appropriate mathematical model with suitably chosen parameters can mimic faulty behavior. This research focuses on the construction of a detailed multi-stage dry vacuum pump model for MB-FDI, and the development of a simple and efficient FDI method to analyze common incipient faults such as particulate deposition and gas leak inside the pump. The pump model features 0-D thermo-fluid dynamics, scalable geometric representations of Roots blower, claw pumps and inter-stage port interfaces, a unified pipe model seamlessly connecting from free molecular to turbulent regimes, sophisticated internal leakage model considering true pump geometry and tribological aspects, and systematic assembly of a multi-stage configuration using single stage pump models. Design of a simple FDI technique for the dry vacuum pump includes staged fault simulations using faulty pump models, parametric study of faulty pump behaviors, and design of a health indicator based on classification. The main research contributions include the developments of an accurate multi-stage dry pump model with many features not found in existing pump models, and the design of a simple MB-FDI technique to detect and isolate the common faults found in dry vacuum pumps. The proposed dry pump model can pave the way for the future development of advanced MB-FDI methods, also performance improvement of existing dry vacuum pumps. The proposed fault classification charts can serve as a quick guideline for vacuum pump manufactures to isolate roots causes from faulty symptoms.

Objective: To examine the association between process quality of inpatient care and risk-adjusted, thirty-day potentially preventable hospital readmission (PPR) rates. Data Sources/Study Setting: This was an observational cross-sectional study of nonfederal acute-care hospitals located in two states California and Florida, discharging Medicare patients with a principal discharge diagnosis of heart failure, acute myocardial infarction, or pneumonia January through December 31, 2007. Data were obtained from the Healthcare Cost and Utilization Project State Inpatient Database of the Agency for Healthcare Research and Quality, Centers for Medicare and Medicaid Services Hospital Compare database, and the American Hospital Association Annual Survey of Hospitals.Study Design: The dependent variable of this study is condition-specific, risk-adjusted, thirty-day potentially preventable hospital readmission (PPR). 3M's PPR software was utilized to determine whether a readmission was potentially preventable. The independent variable of this study is hospital performance for process quality of inpatient care, measured by hospital adherence to recommended processes of care. We used multivariate hierarchical logistic models, clustered by hospitals, to examine the relationship between condition-specific, risk-adjusted, thirty-day PPR rates and process quality of inpatient care, after taking clinical and socio-demographic characteristics of patients and structural and operational characteristics of hospitals into account. Principal Findings: Better performance on the process quality metrics was associated with better patient outcome (i.e., low thirty-day PPR rates) in pneumonia, but not generally in two cardiovascular conditions (i.e., heart failure and acute myocardial infarction). We found no evidence of an interaction between process quality metrics and condition-specific hospital volume with respect to 30-day PPR. Conclusion: Adherence to the process quality metrics currently in use by CMS is associated with risk-adjusted, thirty-day PPR rates for patients with pneumonia, but not with cardiovascular conditions. More evidence-based process quality metrics closely linked to 30-day PPR rates, particularly for cardiovascular conditions, need to be developed.

Cold Rydberg atoms and ultracold plasmas have been studied in the strong-magnetization regime. In this new territory, novel atomic and plasma states---such as guiding-center drift Rydberg attains and strongly magnetized, quasi-neutral, ultracold plasmas---have been created and investigated. The evolution dynamics studies of these exotic diamagnetic forms of matter, made possible by implementing a superconducting magnetic atom trap, revealed rich dynamical features in the systems: The Landau-quantized energy structure has led to entirely different evolutions of the highly excited atoms in laser-excited or drift Rydberg states than in magnetic-field-free cases; and the presence of the strong magnetic field has drastically altered the collisional behavior and expansion dynamics of the plasmas. Furthermore, atom cooling and trapping methodology has been extended in multiple directions. Firstly, laser cooling and magnetic trapping of ground-state atoms has been demonstrated in magnetic; fields exceeding 3 Tesla, representing a 20-fold increase in the field-strength of cold-atom traps. Secondly, the trapping of Rydberg atoms with a lifetime of 80 ms has been achieved. This trapping technique exploits the quasi-free nature of Rydberg electrons, which can be adopted in other forms of Rydberg-atom trapping. Lastly; the trapping of two-component, ultracold plasmas has been demonstrated in a nested Penning-trap configuration. The confinement of quasi-neutral ultracold plasmas allowed us to observe novel effects such as the correlation between the ionic oscillation and the electron energy distribution.

In spite of Ping Chong¡¯s reputation in the American theatre scene, little has been done to explore his artistic works from a fully theorized perspective. In this dissertation, I propose a category of ¡°cultural narrative texts¡± to investigate cultural and historical themes of ¡°culture and the other¡± in Chong¡¯s fascinating ethno-historiographic fables. The poetics and politics of Chong¡¯s narrative texts are the subject of this dissertation. The frames of myth and narratology in their constructive aspects (how the mythic narratives are expressed) provide the poetics part. I adopt the literary approaches of Northrop Frye and Kenneth Burke for their intense studies on image (narrative unit), rhetoric (narrative signification), and emplotment (narrative sequence). In a connective linkage from poetics, the politics part engages the cultural and historical thematics through which I read what is expressed in Chong¡¯s (counter-) myths on people, cultures, and histories. For this complex thematic part, I construe a theoretical bricolage of a broad range of disciplines and methodologies, from psychoanalysis, cognitive science, anthropology, historiography, sociology, to poststructuralism, postcolonialism, and feminism.This dissertation deals with Chong¡¯s ethno-historiographic fables throughout his theatrical career over three decades, examining how his deconstructive myth-making wrestles with the problematic notion of ¡°the other¡± in both local (national) and global aspects. Borrowing Julia Kristeva¡¯s socially informed psychoanalysis, I approach Chong¡¯s concept of ¡°the other¡± as ¡°social abject¡± inhibiting at the margins. I argue that through Chong¡¯s (counter-) myth-making which destabilizes the authority of hegemonic narratives of the incompatible split between the self and the other, multiple voices of the marginalized return, and the monologue of the hegemonic culture is interrupted. In this dissertation, I demonstrate how the performance of Chong¡¯s (counter-) narratives, what I call ¡°voicing back,¡± resist the silence, enabling the marginalized abject to become the subjects of their own desires and histories. This ¡°voicing back¡± in its shared political languages of respect, equality, and justice (toward the others) prepares for the performance of a democracy which is based on the complete modes of speech acts, speaking and listening.

As is the case for DC-DC converters, multi-phase converters require both high-quality power control and high power-density. Although a higher switching frequency not only improves the quality of the converter output but also decreases the size of the converter, it increases switching losses and electromagnetic interference (EMI) noise. Since the soft-switching topologies reduce the switching losses of the converter main switches, the topologies make converters partially independent from the switching frequency. However, the conventional soft-switching topologies have already proposed most of the possible ways to improve converter performance. In addition, the trends of the newly generated power devices reduce the advantages of soft-switching topologies. This critical situation surrounding soft-switching topologies gives research motivations: What features of soft-switching topologies facilitate their practical applications? Given this motivation, the dissertation discusses two aspects = simplifying auxiliary circuits and accounting for the effects of soft-switching operations on the converter control. Engineers working with medium- and high-power multi-phase converters require simplified soft-switching topologies that have the same level of performance as the conventional soft-switching topologies. This demand is the impetus behind one of the research objectives = simplifying the auxiliary circuits of Zero-Voltage-Transition (ZVT) inverters. Simplifying the auxiliary circuits results in both a smaller number of and lower cost for auxiliary components, without any negative impact on performance. This dissertation proposes two major concepts for the simplification - the Single-Switch Single-Leg (S3L) ZVT cell and the Phase-Lock (PL) concept. Throughout an effort to eliminate circulating currents of inductor-coupled (IC) ZVT converters, the S3L ZVT cell is developed. The proposed cell allows a single auxiliary switch to achieve zero-voltage conditions for both the top and bottom main switches, and it achieves the same level of performance as the conventional ZVT cell, as well. This proposal makes IC ZVT topologies more attractive to multi-phase converter applications. Because all of the top main switches generally have identical sequences for zero-voltage turn-on commutations, one auxiliary switch might handle the commutations of all of the top main switches. This possibility introduces the PL concept, which allows the two auxiliary switches to provide a zero-voltage condition for any main switch commutation. In order to compensate for restrictions of this concept, a modified space-vector modulation (SVM) scheme also is introduced. A soft-switching topology changes the duty ratios of the converter, which affects the controllability of the converter. Therefore, this dissertation selects resolution of this issue as one of the research objectives. This dissertation derives the generalized timing equations of ZVT operations, and the generalized equations formulize the effect of ZVT operation on both duty ratios and DC current. Moreover, the effect of SVM schemes is also investigated. An average model of the ZVT converter is developed using both the timing analysis and the investigation of SVM schemes, and small-signal analysis using the average model predicts the steady-state characteristics of the converter.

The overall purpose of this study was to provide information concerning the comparative and competitive abilities of industries and regions within the State and to aid in understanding the changing levels and location of economic activity. Ninety-six counties of Virginia were clustered into eight homogeneous sub-regions by use of clustering analysis and stepwise multiple discriminant analysis. Growth rate differential analysis was performed for each of the eight study sub-regions. Industrial location patterns of the sub-regions of Virginia were examined in terms of location quotients and coefficients of specialization. It was found that the natural resources oriented industries such as agriculture, mining, food production, lumber production, and stone and clay production were highly represented in the rural sub-regions. Manufacturing as a whole was highly represented in the rural industrialized sub-regions; however, the weighted shares of the state total manufacturing employment in these sub-regions were not as great as that of the urban sub-region delineated in the study which showed relatively low representation of manufacturing. There was strong evidence that the manufacturing in the rural sub-regions was in general the rural-oriented manufacturing industries such as food, textile, apparel, stone and clay products, and furniture products. Urban oriented industries such as trade, transportation, contracted construction, services, finance and insurance and government were highly represented in the urbanized subregion. The opposite was true of the rural sub-regions. In the State of Virginia, most of the urban oriented industries were growing faster than the natural resources oriented industries such as agriculture, mining, lumber products, and food products. Unemployment was also declining in terms of percentage change during the 1960-1970 decade. At the sub-regional level, only the urbanized sub-region showed higher than State average growth in both employment and earnings. The other regions showed relative declines in both employment and earnings when compared to the State. Seven of the eight sub-regions of Virginia suffered comparative disadvantages in terms of industrial mixes showing declines in both employment and earnings. The urbanized region benefited from increases in employment and earnings due to both favorable industrial mix and wage structure. Urban oriented industries in general showed comparative abilities in urban areas, while the rural-oriented industries suffered comparative disadvantage in both urban and rural areas. Manufacturing, in general, enjoyed greater comparative abilities in rural areas than in urban areas. Performances of the sub-regions also showed similar trends as the comparative abilities of the regions. All of the sub-regions except the urban sub-region suffered relative declines in their shares of total state employment and earnings. Both rural and urban oriented industries in the urban sub-region showed successful performances, while most of the rural oriented industries suffered competitive disabilities in the rural regions expressed in terms of growth of employment and earnings. The employment projection for the year of 1980 showed that unless the present regional industrial mix for each of the regions is altered, the regional variation in employment growth would be greater during the 1970-1980 decade than in the 1960-1970 decade.