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High step-down dc/dc converters are widely adopted in a variety of areas such as industrial, automotive, and telecommunication. The 48 V power delivery system becomes increasingly popular for powering high-current and low-voltage chips. The Series-Capacitor Buck (SCB) converter doubles the duty ratio and equalizes the current between the two phases. Hard switching has hindered efforts to reduce volume via increased switching frequency, although a monolithically integrated SCB converter has boosted current density. A Series-Resonator Buck (SRB) converter is realized by adding a resonant tank in series with the series capacitor Cs. All switches turn on at zero-voltage (ZVOn), and the low-side switches turn off at zero-current (ZCOff). The design of the SRB converter includes characterizing the design variables' impacts on the converter performances and designing low-loss resonant components as the series resonator. The Series-Resonator Buck converter belongs to the class of quasi-resonant converters. Its resonant frequency is higher than the switching frequency, and its waveforms are quasi-sinusoidal. This work develops a steady-state model of the SRB converter to calculate voltage gain, component peak voltages, and resonant inductor peak current. Each switching cycle is modeled based on the concept of generalized state-space averaging. The soft-switching condition of the high-side switches is derived. The ZVS condition depends on the normalized control variable and the load condition. The gain equation models the load-dependent characteristic and the peak gain boundary. The theoretical peak voltage gain of the SRB converter is smaller than the maximum gain of the SCB converter. A smaller normalized load condition results in a larger peak voltage gain of the SRB converter. The large-signal model of the SRB converter characterizes the low-frequency behavior of the low-pass filters with the series capacitor and the high-frequency behavior of the resonant elements. A design recommendation of t_off f_r<0.5 is suggested to avoid the oscillation between the series capacitor Cs and the output inductors Lo. In other words, the off-duration of the low-side switches is less than half of 1/fr, and therefore the negative damping effect from the parallel resonant tank to the vCs response is reduced. The transfer functions of the SRB converter are presented and compared with those of the SCB converter. The series resonator brings in an extra damping effect to the response of output capacitor voltage. The understanding of the analytical relationships among the resonant tank energy, voltage gain, and component stresses was utilized to guide the converter design of the converter's parameters. A normalized load condition at √2 minimizes the stresses of the series resonator by balancing the peak energy in the resonant elements Lr and Cr. The f_s variation with voltage gain M is less than 10%. The non-resonant components C_s, L_oa, and L_ob are designed according to the specified switching ripples. The ac winding loss complicates the winding design of a resonant inductor. This work replaces the rectangular window with a rhombic window to reduce the eddy current loss caused by the fringing effect. The window ratio k_y is added as a design variable. The impacts of the design variables on the inductance, core loss, and winding loss are discussed. The air-gap length l_g is designed to control the inductance. A larger k_y design results in a short inductor length l_c and a smaller winding loss. The disadvantages include a smaller energy density design and a larger core loss due to the smaller cross-sectional area. In the design example presented in the thesis, the presence of the rhombic shape increases the gap-to-winding distance by two times, and also reduces the y-component of the magnetic field by a factor of two. The total inductor loss is reduced by 56% compared to a conventional design with a rectangular winding window while keeping the same inductance and the same inductor volume. This dissertation implements a resonator, replacing the series capacitor, in an SCB converter. The resultant SRB converter shows a 30% reduction in loss and a 50% increase in power density. The root cause of the divergence issue is identified by modeling the negative damping effect caused by resonant elements. The presented transient design guideline clears the barriers to closed-loop regulation and commercialization of the SRB converter. This work also reshapes winding windows from rectangle to rhombus which is a low-cost change that reduces magnetic loss by half. The theoretical analysis and design procedures are demonstrated in a 200 W prototype with 7% peak efficiency increase compared to the commonly used 30 W commercial SCB product. / Doctor of Philosophy / High step-down dc/dc converters are widely adopted in a variety of areas such as industrial, automotive, and telecommunication areas. The 48 V power delivery system becomes increasingly popular for powering high-current and low-voltage chips. The Series-Capacitor Buck (SCB) converter doubles the duty ratio and equalizes the current between the two phases. Hard switching has hindered efforts to reduce volume via increased switching frequency although a monolithically integrated SCB converter has boosted current density. A Series-Resonator Buck (SRB) converter is realized by adding a resonant tank in series with the series capacitor Cs. All switches turn on at zero-voltage (ZVOn), and the low-side switches turn off at zero-current (ZCOff). The challenges to designing the SRB converter include characterizing the design variables' impacts on the converter performances and designing low-loss resonant components as the series resonator. The resultant SRB converter shows a 30% reduction in loss and a 50% increase in power density. The root cause of the divergence issue is identified by modeling the negative damping effect caused by the resonant elements. The presented transient design guideline clears the barriers of closed-loop regulation and commercialization of the SRB converter. This work also reshapes winding windows from rectangle to rhombus, which is a low-cost change that reduces magnetic loss by half. The theoretical analysis and design procedures are demonstrated in a 200 W prototype with 7% peak efficiency increase compared to the commonly used 30 W commercial SCB product.

In this work, fluorous metal organic framework 1 (FMOF-1) and its isomorphic structures are investigated for both sensing and filtration applications. In chapter 2 both FMOF-1 and its acetone derivative, aFMOF-1, are shown to exhibit an unusual photoluminescent behavior by having a "turn-on" emission when exposed to vacuum. This baroluminescence occurs at different rates depending on specific gas, allowing FMOF-1 and aFMOF-1 to not only act as vacuum gauges, but also potentially act as sensors for gas identification. Chapter 3 focuses on chemical sensing properties (chemosensing) of the newly discovered second methanol derivative of FMOF-1, mFMOF-2. mFMOF-2 has been shown to be air and water stable, however exposure to volatile organic compounds (VOCs) will cause quenching or shifts in emission. Finally, chapter 4 investigates the ability of combining MOFs with more traditional sorbents to investigate the possibility of a hybrid material that takes advantage of both materials. MOFs have long been investigated for their filtration properties, however the high cost of synthesis of MOFs compared to the cost-efficient common filters hamstrings their real-world implementations. Combining a small percentage of FMOF-1 with activated carbon is seen to improve the filtration efficiency and to increase the hydrophobic properties. This hybrid filtration material avoids the problems associated with the cost of synthetic filtration materials since only 0.1% mass additive is shown to yield significantly improved results.

The Eudaimonic turn: Well-being in Literary Studies (2013), a study by Pawelski et al, sheds light on a recent turn in literary studies. The eudaimonic approach entails that texts are examined with the help of a hermeneutic of affirmation rather than the sceptical, suspicious methods of the deconstruction and post-structuralism. Pawelski et al’s text is drawn upon in this study because it corresponds to the way in which Marlene van Niekerk utilises themes such as relationships, friendship and loss in Die sneeuslaper (2009). The eudaimonic turn focusses on the way in which complex interpersonal connections are able to add to an individual’s well-being through positive as well as negative processes. Die sneeuslaper is mainly a reflection on what it means to be an author. However, it also raises important questions about the nature of being. The four short stories provide different perspectives on friendship, on how friendship can sometimes be problematic and even a nuisance, but also how relations with others repeatedly prove to be beneficial to a person’s well-being. In my study, the relational theme of friendship in Die sneeuslaper is studied from a eudaimonic point of view. Kaja Silverman’s text, Flesh of my Flesh (2009), is referred to in order to shed light on the term relationality. The relational themes of finitude (or mortality) and interpersonal connection are clearly present in Van Niekerk’s text. Although the death of a beloved friend causes trauma in Die sneeuslaper, the trauma proves to have positive effects in the form of posttraumatic growth, comfort and acceptance as time goes by. Comfort is also construed through the creation and appreciation of a work of art like Die sneeuslaper. Cognitive narratology is referenced to show how Marlene van Niekerk overthrows and plays with fixed ideas regarding relationality and friendship, causing the reader to converse with the text. Views on friendship held by thinkers such as Aristotle, Montaigne, Lacan, Kierkegaard and Derrida are referenced to give Van Niekerk’s use of the theme in Die sneeuslaper a certain context. This context represents the fixed frames of thinking generally applicable with regard to friendship. When a reader is willing to critically interpret these as well as personal frames of reference, it provides him or her the opportunity to contemplate reality from new perspectives. In Die sneeuslaper the reader is continually challenged to question existing frames of reference by means of never ending methods (resembling a Möbius-strip) and strange notions. This study concludes with the notion that it is necessary for artists (like the writers in Die sneeuslaper) to reflect differently on reality, so that readers may be inspired to also view reality in a different light. This will result in a broader view of reality, which in turn will have a more defining influence on personal well-being. / MA (Afrikaans and Dutch), North-West University, Potchefstroom Campus, 2014

The Eudaimonic turn: Well-being in Literary Studies (2013), a study by Pawelski et al, sheds light on a recent turn in literary studies. The eudaimonic approach entails that texts are examined with the help of a hermeneutic of affirmation rather than the sceptical, suspicious methods of the deconstruction and post-structuralism. Pawelski et al’s text is drawn upon in this study because it corresponds to the way in which Marlene van Niekerk utilises themes such as relationships, friendship and loss in Die sneeuslaper (2009). The eudaimonic turn focusses on the way in which complex interpersonal connections are able to add to an individual’s well-being through positive as well as negative processes. Die sneeuslaper is mainly a reflection on what it means to be an author. However, it also raises important questions about the nature of being. The four short stories provide different perspectives on friendship, on how friendship can sometimes be problematic and even a nuisance, but also how relations with others repeatedly prove to be beneficial to a person’s well-being. In my study, the relational theme of friendship in Die sneeuslaper is studied from a eudaimonic point of view. Kaja Silverman’s text, Flesh of my Flesh (2009), is referred to in order to shed light on the term relationality. The relational themes of finitude (or mortality) and interpersonal connection are clearly present in Van Niekerk’s text. Although the death of a beloved friend causes trauma in Die sneeuslaper, the trauma proves to have positive effects in the form of posttraumatic growth, comfort and acceptance as time goes by. Comfort is also construed through the creation and appreciation of a work of art like Die sneeuslaper. Cognitive narratology is referenced to show how Marlene van Niekerk overthrows and plays with fixed ideas regarding relationality and friendship, causing the reader to converse with the text. Views on friendship held by thinkers such as Aristotle, Montaigne, Lacan, Kierkegaard and Derrida are referenced to give Van Niekerk’s use of the theme in Die sneeuslaper a certain context. This context represents the fixed frames of thinking generally applicable with regard to friendship. When a reader is willing to critically interpret these as well as personal frames of reference, it provides him or her the opportunity to contemplate reality from new perspectives. In Die sneeuslaper the reader is continually challenged to question existing frames of reference by means of never ending methods (resembling a Möbius-strip) and strange notions. This study concludes with the notion that it is necessary for artists (like the writers in Die sneeuslaper) to reflect differently on reality, so that readers may be inspired to also view reality in a different light. This will result in a broader view of reality, which in turn will have a more defining influence on personal well-being. / MA (Afrikaans and Dutch), North-West University, Potchefstroom Campus, 2014

Turn-taking is a fundamental process that governs social interaction. When humans interact, they naturally take initiative and relinquish control to each other using verbal and nonverbal behavior in a coordinated manner. In contrast, existing approaches for controlling a robot's social behavior do not explicitly model turn-taking, resulting in interaction breakdowns that confuse or frustrate the human and detract from the dyad's cooperative goals. They also lack generality, relying on scripted behavior control that must be designed for each new domain. This thesis seeks to enable robots to cooperate fluently with humans by automatically controlling the timing of multimodal turn-taking. Based on our empirical studies of interaction phenomena, we develop a computational turn-taking model that accounts for multimodal information flow and resource usage in interaction. This model is implemented within a novel behavior generation architecture called CADENCE, the Control Architecture for the Dynamics of Embodied Natural Coordination and Engagement, that controls a robot's speech, gesture, gaze, and manipulation. CADENCE controls turn-taking using a timed Petri net (TPN) representation that integrates resource exchange, interruptible modality execution, and modeling of the human user. We demonstrate progressive developments of CADENCE through multiple domains of autonomous interaction encompassing situated dialogue and collaborative manipulation. We also iteratively evaluate improvements in the system using quantitative metrics of task success, fluency, and balance of control.

理性概念所具備的統一性特徵在傳統的形上學背景之下表現為一種普遍的統一學說，然而這樣的論點在當代受到很大的挑戰，當代思想中很多都表現為一種多元主義的立場，對於理性統一性的論點多有批判。於是乎一場一與多之間的哲學辯論就此展開。哈伯馬斯對於理性統一性有其獨特的見解，重新考慮在多元之中理性統一性的可能性。基本上哈伯馬斯採取跳脫形上學立場，不在一與多兩者間的對立為任何一方進行辯護，而是提出一種新的見解，由後形上學的立場來談在多元中理性統一性的可能性。 哈伯馬斯認為現今存在著兩類針鋒相對的觀點，一種是有鑑於當代形上學統一性的喪失而努力回歸前康德時代的形上學，另一種則是以被壓制的多元性向統一性思想提出抗議。為了要釐清其中有關一與多之間的對立與關聯，哈伯馬斯對於傳統以來一與多之間的論點提出了個人的見解，同時也對當代反對統一性的相關論點做討論，進而提出自己的看法以求一條新的解決之道，試著調和一與多之間的對立性。本論文將透過對後形上學思想趨勢的討論，說明哈伯馬斯重建理性概念的進路及其對不同立場的學者所抱持的態度。

東柏林圍牆倒塌，金磚四國崛起，使得第三世界國家的經濟能力大幅提升，對能源及石化產品的需求也日益增加，促使全球對石化產業之投資大幅暴增且投資規模也較前期更大。為能加速獲利，業主經常要求統包工程公司能縮短1/3之工期。因此，統包工程公司需不斷研發及創新，並使用有別於傳統模式之作業方法，才可達成此縮短工期之目標。 近年由於電腦軟硬體進步神速及網際網路之普及化，提供了一個資訊交換的新環境。許多跨國作業、同步工程之應用系統紛紛被提出，但仍無法有效解決當前之問題，反而形成許多自動化孤島之資訊作業。 本研究主要目的在於探討如何利用先進資訊科技技術與國際共通的資訊標準規範，建立製程工廠統包工程所需之「建廠資訊生命週期管理」系統，將重要資訊予以電子化、結構化及標準化。透過電腦網路通訊及資料庫技術，使建廠過程能提供優良資訊品質，供參與建廠人員能透過此透明化之系統，使資訊得以整合與共享，確保資訊品質之完整、正確及一致性。 建廠工程之作業有許多不同的階段，本研究擬針對「建廠資訊生命週期管理」系統提出完整之規劃架構，但因本系統相當龐大，無法於短時間內完成全部之系統雛型，故，本著「Think Big, Start Small, Scale Fast」之理念，本研究將先對產製最多資訊之設計階段先行建立系統雛型，作為示範性之先導開發工作。本研究所獲得之主要結論如下: 一、 導入標準資訊規範是正確途徑 二、 為縮短建廠時間，需建立資訊整合與共享環境 三、 要提升統包工程公司之競爭力，需建立全球化作業平台 四、 要提升資訊品質需將文件中心轉變為資訊中心 關鍵字: 資訊生命週期管理、製程工廠、統包工程、圖形交換標準 建廠資訊交換標準、建廠工程活動、資訊品質、標準資訊規範 / The 3rd world economy has been largely improved resulting from the collapse of the Eastern Berlin wall and the rise of the Brics. Since then, the investment in the petroleum/chemical industries is increased triggered from a strong demand of the energy and petroleum/ chemical products. To expedite the profit return, the clients will usually request the turnkey project company to condense the plant’s engineering time to at least 1/3 of the original scheduled. Therefore, the turnkey project company needs to continuously engage in its R&D and create an innovation method different from the traditional one to fulfill with clients’ expectation. Owing to the rapid progress of the hardwares and softwares together with the popularity of the internet, it provids a new environment for the information exchange. Although numerous applications for global operation and concurrent had been announced, it still couldn’t resolve the existing problems, instead, it caused another problem and leads the information to the Islands of automation. The purpose of this study is to find out how to utilize the advanced information technology and worldwide standadized information specification to establish a 「Plant Information Lifecycle Management-PILM」system for the Process Plant. It is the hope that through the aforesaid system, user can transform their important information into a electronic、structured and standadized formular. In addition, by using the Internet communation and database technology, it can help the user to integrate and share information through this transparent system and ensure the completeness、correctness and consistency of the information quality. There are many phases in the plant engineering operation. Although this study is striving to provide a complete designing framework for the system of 「Plant Information Lifecycle Management」, however ,it is definitely impossible to complete the whole system prototype for this huge system during such a short period. Therefore, this study will focus only on the “Design Phase” based on the core principle “Think Big, Start Small and Scale Fast”. Most of the information will be emerged during the Design Phase, so that, a system prototype for this phase will be designed as an initiative development model. The major conclusions for this study are as follows: 1. The international standards should be adopted by the Turnkey project company. 2. To reduce the plant engineering time, an integral and share environment (the PILM system) should be built. 3. To enhance the competitiveness of the Turnkey project company, a global application platform (i.e. The PILM system) needs to be established. 4. To lift the information quality, the document centric needs to be transformed to data centric. Keyword: ISO 10303, STEP, ISO 15926, Plant Information Lifecycle Management , UML, EPC(Engineering/Procurement/Construction), Turn-Key

Unter dem Begriff des Poststrukturalismus wird eine disparate, auf den Axiomen des Strukturalismus aufbauende und diese zugleich überwindende Strömung verstanden, die sowohl innerhalb der Sozial- und Kulturwissenschaften als auch in interdisziplinär organisierten Feldern wie den Gender Studies von großer Tragweite ist. Geteilt wird die Auffassung, dass kulturelle Phänomene allgemein sprachlich strukturiert sind. Seine Tendenz, unter die Oberfläche vermeintlich stabiler, monolithischer Strukturen zu schauen, qualifiziert den Poststrukturalismus für eine Anwendung auf genderwissenschaftliche Kategorien wie Weiblichkeit und Männlichkeit, deren Bedeutung nicht aus sich selbst erwächst, sondern die als Signifikate innerhalb eines (phallokratischen) Systems zu denken sind.

Dans ce mémoire, je présente mes études sur une stratégie efficace développée pour la synthèse de cétones homoallyliques substituées à partir de l’addition en cascade de réactifs de Grignard vinyliques substitués sur des α-amino esters catalysée par des sels de cuivre. L’utilisation de ces cétones homoallyliques a permis d’obtenir des mimes peptidiques comprenant un isostère de type hydroxyéthylène du lien amide. L’étape clé de cette stratégie repose sur la synthèse de cétones homoallyliques substituées intermédiaires à partir de la réaction d’additions en cascade catalysée au cuivre, de bromure de β,β-diméthylevinyle magnésium sur des analogues d’esters de la phénylalanine et de la sérine. Les cétones homoallyliques résultantes sont réduites sélectivement en alcool, la liaison double est clivée oxydativement et l’acide carboxylique résultant est couplé à un acide aminé. Afin d’évaluer l’effet qu’ont le remplacement du lien amide central dans un coude β par un hydroxyéthylène et de la présence d’un gem diméthyle sur la chaîne carbonée sur la conformation tridimensionnelle adoptée par les tripeptides générés, des analyses à l’état solide par diffraction aux rayons X, des analyses en solution par la spectroscopie RMN et des expériences de type NOESY ont été réalisées. Ces études ont permis de définir un nouveau type de coude β. La présence de pont hydrogène intramoléculaire et l’effet de restriction de conformation induit par le gem diméthyle, généralement appelé effet Thorpe-Ingold, favorisent la formation d’un coude β. / In this thesis, I discuss my studies toward the synthesis of substituted homoallylic ketones from the copper-catalyzed cascade addition of substitued vinyl Grignard reagents to carboxylic esters. The homoallylic ketones were used to provide different peptidomimetics containing a hydroxyethylene isostere instead of an amide bond. The methyl ester of phenylalanine and serine derivatives were reacted in copper-catalyzed cascade additions of substitued vinylmagnesium bromide to provide substitued homoallylic ketone intermediates. Selective reduction of the ketone to an alcohol, oxidative cleavage of the double bond, followed by peptide coupling with amino acid lead to the desired peptidomimic. The influence of changing the central amide bond for a hydroxyethylene isostere in a β-turn and the effect of a gem dimethyl group on the backbone conformation adopted by the newly synthesized tripeptides, were studied by X-ray diffraction and solution NMR spectroscopy using NOESY experiments. From these studies, it was revealed that the iso-butyric acid hydroxyethylene isomer induced a β-turn-like conformation, and may serve as a novel scaffold for peptide mimicry.