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Thermoelectric materials are capable of direct conversion of thermal energy to electrical energy and vice versa. Their applications include thermoelectric coolers, generators, as well as sensors. Conventional thermoelectric devices consist of multiple units of p-type and n-type semiconducting elements, in which electrical current and heat flux flow parallel to each other. In contrast, transverse thermoelectric devices could decouple electrical current and heat flux such that they flow perpendicular to each other. Transverse thermoelectricity could be realized in single-phase anisotropic materials or composite materials with engineered anisotropy. Studies have shown that composite transverse thermoelectric materials could provide a better performance than their single-phase counterparts. In this dissertation proposal, two configurations of transverse thermoelectric composites are examined using both analytical and numerical methods. Mathematical models are established to calculate the effective properties of anisotropic thermoelectric composites by analyzing the representative unit cells using the Kirchhoff circuit law (KCL) and the Thevenin’s theorem followed by tensor transformation. Thermoelectric figure of merit (ZT), power factor, as well as cooling performance (maximum cooling temperature ΔTmax) of transverse thermoelectrics are studied. Comparisons between the mathematical models and numerical simulation showed good agreement, while some discrepancies are observed and discussed. Since transverse composite thermoelectrics can decouple the electrical and thermal transports, they can offer new opportunities for device design including thin film sensors and cascading coolers, as well as for performance enhancement such as improved power factors. / Mechanical Engineering

The next generation of power converters not only must meet the characteristics demanded by the load, but also has to meet some specific requirements like limited space and high ambient temperature etc. This needs the power converter to achieve high power density and high temperature operation. It is usually required that the active power devices operate at higher switching frequencies to shrink the passive components volume. The power semiconductor devices for high frequency high density power converter applications have been investigated. Firstly, the methodology is developed to evaluate the power semiconductor devices for high power density applications. The power density figure of merit (PDFOM) for power MOSFET and IGBT are derived from the junction temperature rise, power loss and package points of view. The device matrices are generated for device comparison and selection to show how to use the PDFOM. A calculation example is given to validate the PDFOM. Several semiconductor material figures of merit are also proposed. The wide bandgap materials based power devices benefits for power density are explored compared to the silicon material power devices. Secondly, the high temperature operation characteristics of power semiconductor devices have been presented that benefit the power density. The electrical characteristics and thermal stabilities are tested and analyzed, which include the avalanche breakdown voltage, leakage current variation with junction temperature rise. To study the thermal stability of power device, the closed loop thermal system and stability criteria are developed and analyzed. From the developed thermal stability criterion, the maximum switching frequency can be derived for the converter system design. The developed thermal system analysis approach can be extended to other Si devices or wide bandgap devices. To fully and safely utilize the power devices the junction temperature prediction approach is developed and implemented in the system test, which considers the parasitic components inside the power MOSFET module when the power MOSFET module switches at hundreds of kHz. Also the thermal stability for pulse power application characteristics is studied further to predict how the high junction temperature operation affects the power density improvement. Thirdly, to develop high frequency high power devices for high power high density converter design, the basic approaches are paralleling low current rating power MOSFETs or series low voltage rating IGBTs to achieve high frequency high power output, because power MOSFETs and low voltage IGBTs can operate at high switching frequency and have better thermal handling capability. However the current sharing issues caused by transconductance, threshold voltage and miller capacitance mismatch during conduction and switching transient states may generate higher power losses, which need to be analyzed further. A current sharing control approach from the gate side is developed. The experimental results indicate that the power MOSFETs can be paralleled with proper gate driver design and accordingly the switching losses are reduced to some extent, which is very useful for the switching loss dominated high power density converter design. The gate driving design is also important for the power MOSFET module with parallel dice inside thus increased input capacitance. This results in the higher gate driver power loss when the traditional resistive gate driver is implemented. Therefore the advanced self-power resonant gate driver is investigated and implemented. The low gate driver loss results in the development of the self-power unit that takes the power from the power bus. The overall volume of the gate driver can be minimized thus the power density is improved. Next, power semiconductor device series-connection operation is often used in the high power density converter to meet the high voltage output such as high power density boost converter. The static and dynamic voltage balancing between series-connected IGBTs is achieved using a hybrid approach of an active clamp circuit and an active gate control. A Scalable Power Semiconductor Switch (SPSS) based on series-IGBTs is developed with built-in power supply and a single optical control terminal. An integrated package with a common baseplate is used to achieve a better thermal characteristic. These design features allow the SPSS unit to function as a single optically controlled three-terminal switching device for users. Experimental evaluation of the prototype SPSS shows it fully achieved the design objectives. The SPSS is a useful power switch concept for building high power density, high switching frequency and high voltage functions that are beyond the capability of individual power devices. As conclusions, in this dissertation, the above-mentioned issues and approaches to develop high density power converter from power semiconductor devices standpoint are explored, particularly with regards to high frequency high temperature operation. To realize such power switches the related current sharing, voltage balance and gate driving techniques are developed. The power density potential improvements are investigated based on the real high density power converter design. The power semiconductor devices effects on power density are investigated from the power device figure of merit, high frequency high temperature operation and device parallel operation points of view. / Ph. D.

在探討殊價慾望的規範性意義時，必先瞭解殊價慾望在規範意義上的爭議，而欲瞭解其爭議所在，則首先需從殊價慾望的定義與特性著手。然而困難之處就在於，殊價慾望的定義不僅有失明確，且有因人而異、各陳己見的情況，甚至Musgrave本人亦數度更改對殊價慾望意義的認定。 殊價慾望與殊價財在意義與所具備之特性，眾學者認知上的差異性頗大。主要的差異，一為殊價慾望與殊價財之間觀念的混淆，一為對殊價慾望本身意見之分歧。對於前者，Musgrave在說明殊價慾望與殊價財的意義與特性時，有其清楚的區別。因此，依Musgrave的原意，對殊價慾望的探討才應是較為適切的方向。至於後者，則引發了學者之間對於殊價慾望在傳統規範性公共經濟學中，是否具有規範性意義的爭辯。在消費者主權的光環下，嚴守新古典福利經濟學的學者對其提出嚴厲的批判。 在殊價慾望或殊價財意識型態方面爭論不休之餘，已有多位學者進一步探求殊價財是否亦適用極大化福利之模型分析，並藉由特殊的模型設定推導出殊價財的最適條件，計有一、外部性（效用依存性），二、資訊與學習效果，三、社會的偏好，四、社會計劃者，以及五、福利經濟的事後概念。然而這些學者仍舊以財貨之特殊設定來試圖解釋殊價慾望之規範性的方法，可信度方面不得不有所保留；此外，即使較著重於最適條件的推導，但仍因各位學者對於殊價財特性之認知不一，所特殊設計之模型各異，致使其所得出之殊價財最適條件顯然只能適用其所認知之殊價財，實不足以完整涵蓋殊價慾望的真義。 晚近多有學者以不同角度來解釋殊價慾望。他們已認清除非擺脫新古典個人主義所代表之典範，轉移至另一個典範之內探討，方有釐清殊價慾望的可能。包括從個人偏好的分類出發，提出除了個人的私人偏好外，尚有個人之社會偏好，為一種對於整體經濟社會運行法則的偏好。其次，亦有藉由辯證提供殊價財的制度觀點來證明殊價慾望與殊價財的規範性意義，並且認清了除了消費者主權以外，尚存在如選民主權之其他主權。另外，亦有借重哲學思考，以可能性條件論述殊價慾望的滿足，認為殊價慾望必使得經濟學需納入道德正義的考量，因此必為社會經濟學。並將之應用於歸類並支持政府的一些職責，諸如制度上的設計安排，目的在使得自由市場得以運作，並得以有效率地運作，更可以人性化地運作。然而其中仍有許多不足之處，甚至誤解的情形。 問題的癥結確實在於新古典經濟理論的個人主義並不切合實際。真正的個人主義對於社會人行為的分析，是無法與其身處之社會環境以及複雜的人際關係相分離的。因此為了擺脫不合宜的分析方法，首先必需透過解釋學理論的第一人稱觀點解釋決定的形成與選擇，必基於瞭解個人如何認知。因此第一人稱觀點必成為客觀之主觀論者理論，同時社會科學研究者亦必須投入所欲分析的世界。並在輕「均衡」而重「認知」的理解下，考量第一人稱觀點所重視的動機、利益，與人際關係的交互影響，並捨棄於解釋人類行為並無助益之均衡理論、部分的預測行為，以及細瑣的數學推導。 因此，社會科學係研究「社會問題」，即人與人之間關係的研究，對於同時具備「經濟人」與「社會人」的身份的個人，其私人慾望與社會慾望的分類當依人際關係的有無加以區分。並對個人主觀之偏好輔以「第三者評判」，或某種「公共的正確性準則」。另外亦釐清慾望衡量的原則，以及構成原則與衡量法原則之間的不同之處。最後則詳加分析由消費者主權、私人主權，擴展到個人主權，各個主權原則之間的關係，清楚可知消費者主權實非唯一最重要的主權原則。 如此則殊價慾望之內涵已顯露無疑。其包含了利他的慾望、規範強制的慾望，以及集體狀態的慾望。由是可得本文對於殊價慾望意義之重要結論：係殊價慾望決定了財貨的殊價性，而非財貨提供的特性使其成為殊價財。且殊價慾望必涉及個人的社會慾望，亦絕非外部性所足堪解釋，同時並不因所得分配正義的達成而消滅。對於由政府提供滿足殊價慾望之規範性意義，亦因人際關係愈顯疏離的今日，共同的規範若不經由公權力執行，即合法的強制力，勢必已無法約束利害攸關的人際互動，而得到證實。

International Telemetering Conference Proceedings / October 22-25, 2001 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Automating Telemetry Tracking Systems Operational Readiness Tests is a concept that was introduced at White Sands Missile Range in the early 1980’s. The idea was to determine the condition of a Telemetry Tracking System in a reliable manner in a short time as possible. A series of RF and Servo Tests designed to determine the condition of a Telemetry Tracking System was implemented using HP BASIC. The latest personal computers are faster and have more storage capacity plus the capability to be programmed in higher level languages such as C/C++ and LabView. This technology makes it easier to automate system tests. Many of these tests need to be conducted just prior to supporting a mission. Some tests are required to be performed on mobile systems after moving the system from one location to another, especially if the move was over long distances and rugged terrain. Tests such as G/T are conducted before each mission because it yields accurate information on the Figure of Merit, or, System Sensitivity. Noise Figure Measurements are more difficult to perform to determine the System Sensitivity since modern RF Subsystems have pre-amplifiers with Noise Figures of less than 1.0 dB. The “down-sizing” of personnel increases the possibility of failure in mission support scenarios due to the many critical readiness tests needed to assess the Telemetry Tracking Systems. Also, conventional test methods can be time consuming and are subject to human error. This paper describes four critical tests that have been automated to improve reliability of the test data and decrease the amount of time required to conduct the tests. The “C/C++” language was used to write the automation programs. More tests will be automated later.

published_or_final_version / Social Work and Social Administration / Doctoral / Doctor of Philosophy

Esta dissertação tem como objeto a análise da atuação judicial no âmbito dos processos de recuperação judicial de empresas, regulados pela Lei nº 11.101 de 9 de fevereiro de 2002 (\"LRE\"). No primeiro capítulo, são introduzidas as limitações do trabalho e as principais questões a serem respondidas ao longo do texto. No segundo capítulo, são expostos os panoramas histórico e jurídico da LRE, para que se extraiam os verdadeiros objetivos tutelados pela lei e o diálogo destes objetivos com a atuação do Poder Judiciário. No terceiro capítulo, são propostos três níveis de intervenção judicial no bojo do processo de recuperação, sendo eles: (a) o controle de legalidade estrita, por meio do qual o juiz verificará a observância aos requisitos e vedações impostos pela LRE ao conteúdo do plano de recuperação e à sua votação; (b) o controle de legalidade material ou controle de juridicidade, por meio do qual o juiz avaliará se o conteúdo do plano e sua votação atendem aos princípios gerais orientadores do ordenamento brasileiro; e (c) o juízo de viabilidade, por meio do qual o juiz, usando de critérios objetivos sugeridos pela doutrina, avaliaria o mérito do plano de recuperação judicial para averiguar se, além de atenderem aos critérios de legalidade, as disposições do plano de recuperação atingem os objetivos traçados pela LRE, no sentido de tutela da empresa viável e tutela institucional do crédito. No quarto capítulo, são retomadas as conclusões alcançadas ao final de cada um dos subcapítulos. / This study aims at the analysis of the role played by judges in connection to the proceedings of judicial corporate reorganization established under Federal Law No. 11.101, dated February 9, 2002 (\"LRE\"). In the first chapter, the limitations to this study and the main questions to be answered herein are introduced. In the second chapter, the legal and historical backgrounds of LRE are presented. In the third chapter, we propose three (3) different levels of judicial intervention related to the judicial corporate reorganization procedure: (a) the control of strict legality, by means of which the judge will monitor whether the reorganization plan and the deliberation organized for the plan to be voted are in compliance with the requirements and prohibitions imposed by LRE; (b) the control of substantive legality, through which the judge will assess whether the plan\'s content and its voting meet the general principles that govern Brazilian legal system; and (c) a feasibility judgment, by means of which the judge, using some objective criteria suggested by doctrine, evaluates the merits of the judicial reorganization plan to determine whether, the recovery plan provisions reach the goals set by LRE, in the sense of protection of viable companies and institucional credit.