Le but de ce projet, en collaboration avec Héma-Québec, était de développer une méthode point de service (POC) pour la quantification des immunoglobulines A (IgA) dans un petit volume de plasma humain. Les IgA jouent un rôle important au niveau de notre système immunitaire, surtout au niveau des bio fluides sur les muqueuses comme la salive. On peut les retrouver normalement dans le plasma à des concentrations plus grandes que 2000 ng/mL pour la majorité des gens. Dans le cas d’une personne immunosupprimée, une concentration plus basse que 500 ng/mL est observée. La déficience en IgA est souvent associée à des maladies auto-immunes comme la maladie de Crohn. Ces individus peuvent éprouver un choc anaphylactique à la suite d’une transfusion de sang, ce qui nous motive à utiliser la résonance des plasmons de surface (SPR) sur place à des collectes de sang et dans les milieux hospitaliers. Pour réaliser ce capteur d’immunodéficience en IgA, un anticorps primaire spécifique aux IgA fut lié à un peptide formant une monocouche auto-assemblée sur une surface d’or du capteur SPR. Un deuxième anticorps a été utilisé pour quantifier spécifiquement cet analyte dans une matrice humaine complexe. Plusieurs étapes ont été optimisées pour obtenir une limite de détection basse, soit l’étape d’immobilisation de l’anticorps de capture, le type d’anticorps, le pH pour l’immobilisation, la détection secondaire, la validation dans différentes matrices biologiques, parmi d’autres. Le capteur a été validé avec quelques échantillons cliniques et la réponse SPR fut comparée avec ELISA. Ainsi, nous anticipons que cette méthode pourrait être utile à des collectes de sang pour assurer les réserves de sang déficient en IgA. / The goal of this project, in collaboration with Héma-Québec, was to develop a point-ofcare (POC) method to quantify immunoglobulin A (IgA) in a small volume of human plasma. Immunoglobulin A play an important role in immunity, specifically in biofluids on mucosaes like saliva. It can generally be found in plasma at concentrations higher than 2000 ng/mL for most people. In the case of an immunosuppressed individual, a concentration under 500 ng/mL is observed. IgA-deficiency is often associated with autoimmune diseases, such as Crohn’s disease. These individuals may experience an anaphylactic shock following a blood transfusion, which motivated us to use surface plasmon resonance (SPR) on site at blood drives and in a hospital setting. SPR quantifies the interactions between biomolecules. It is a complementary technique to ELISA that can test more rapidly individuals susceptible of being IgA-deficient in a hospital setting or at blood drives. To develop an IgA SPR sensor, a specific capture antibody to IgA was bound to a peptide monolayer on the gold surface. A second antibody was used to specifically quantify IgA in a complex matrix. Multiple steps were optimized to achieve the low detection limits required for IgA detection, such as the capture antibody immobilisation step, type of antibody, pH of immobilisation buffer, secondary detection, validation in different biological matrices, among others. The SPR sensor was validated with a few clinical samples, and compared to ELISA, to demonstrate the potential. As such, we envision that this rapid method may be used at blood drives to ensure sufficient reserves of IgA-deficient blood.

Power electronics applications in high power are normally large, expensive, spatially distributed systems. These systems are typically complex and have multiple functions. Due to these properties, the control algorithm and its implementation are challenging, and a different approach is needed to avoid customized solutions to every application while still having reliable sensor measurements and converter communication and control. This thesis proposes a synchronous digital control architecture that allows for the communication and control of devices via a fiber optic communication ring using digital technology. The proposed control architecture is a multidisciplinary approach consisting of concepts from several areas of electrical engineering. A review of the state of the art is presented in Chapter 2 in the areas of power electronics, fieldbus control networks, and digital design. A universal controller is proposed as a solution to the hardware independent control of these converters. Chapter 3 discusses how the controller was specified, designed, implemented, and tested. The power level specific hardware is implemented in modules referred to as hardware managers. A design for a hardware manager was previously implemented and tested. Based on these results and experiences, an improved hardware manager is specified in Chapter 4. A fault tolerant communication protocol is specified in Chapter 5. This protocol is an improvement on a previous version of the protocol, adding benefits of improved synchronization, multimaster support, fault tolerant structure with support for hot-swapping, live insertion and removals, a variable ring structure, and a new network based clock concept for greater flexibility and control. Chapter 6 provides a system demonstration, verifying the components work in configurations involving combinations of controllers and hardware managers to form applications. Chapter 7 is the conclusion. VHDL code is included for the controller, the hardware manager, and the protocol. Schematics and manufacturing specifications are included for the controller. / Master of Science

This dissertation investigates the correlation between semiotic theory and the way that gendered subjectivity is represented in contemporary South African art. The phenomenon of signification is central to the semiotic theories of the Bulgarian semiotician and psychoanalyst Julia Kristeva. Semiotics can be described as the science of the sign that considers the way in which artists express their personal experience in art making. In this investigation I refer mainly to women's artworks, although the concept of gendered subjectivity in the work of male artists is also discussed. This particular research investigates the symbolic relations of culture in gender terms, that explores the apparent contradictions of subjectivity inherent in capitalist patriarchal society. / Art History, Visual Arts & Music / M.A. (Visual Arts)

<p>У тези су предложена два унапређена алгоритма управљања<br />асинхроним мотором у условима када је број сензора који се користи у<br />погону минималан. Број сензора који се користи у повратној спрези<br />управљачког алгоритма сведен је на само један струјни сензор који<br />мери струју једносмерног међукола погонског инвертора. Предложене<br />методе елиминишу карактеристично изобличење реконструисаних<br />фазних струја и постижу бољи квалитет и перформансе управљања у<br />односу на конвенционалну методу. Сва аналитичка разматрања у тези<br />су праћена одговарајућим експерименталним резултатима, који<br />потврђују ефикасност предложених метода управљања.</p> / <p>U tezi su predložena dva unapređena algoritma upravljanja<br />asinhronim motorom u uslovima kada je broj senzora koji se koristi u<br />pogonu minimalan. Broj senzora koji se koristi u povratnoj sprezi<br />upravljačkog algoritma sveden je na samo jedan strujni senzor koji<br />meri struju jednosmernog međukola pogonskog invertora. Predložene<br />metode eliminišu karakteristično izobličenje rekonstruisanih<br />faznih struja i postižu bolji kvalitet i performanse upravljanja u<br />odnosu na konvencionalnu metodu. Sva analitička razmatranja u tezi<br />su praćena odgovarajućim eksperimentalnim rezultatima, koji<br />potvrđuju efikasnost predloženih metoda upravljanja.</p> / <p>This thesis proposes two improved and robust induction motor drive control<br />methods, in the case when there is a minimal number of sensors for<br />providing feedback signals. Number of used sensors is reduced to only one<br />current sensor measuring the inverter dc-link current. Proposed methods<br />cancels offset jitter-like waveform distortion present in the reconstructed<br />motor phase currents, and achieves higher quality and drive performance<br />regard to conventional current reconstruction mechanism. Effectivness of the<br />proposed methods are verified on developed HIL (hardware-in-the-loop)<br />platform and laboratory induction motor drive prototype.</p>

Dans cette thèse, nous nous proposons d’investiguer les signaux expérimentaux provenant des transmissions par courroie, afin d’envisager par exemple le diagnostic de la tension. N’étant pas issu du domaine de la Mécanique, nous présentons donc une bibliographie exhaustive et thématique sur la théorie et l’expérimentation dans les systèmes transmissions par courroie. Le résumé de ce travail a permis de choisir une approche de modélisation mécanique correspondant au mieux aux conditions réelles de fonctionnement de notre système. Elle inclut les variations temporelles dans la vitesse de rotation du moteur qui entraîne la transmission entière et des changements dans la tension de la courroie. Malheureusement, nous n’avons pas réussi à implémenter numériquement les équations de simulation. Néanmoins, les conclusions que nous en tirons nous aident par la suite à mieux comprendre et interpréter les résultats expérimentaux obtenus, après application de l’ensemble des procédures de Traitement du signal. Notre panoplie d’outils de traitements numériques est tirée d’une longue analyse comparative des différents algorithmes de Traitement du Signal existants, dédiés à la surveillance, au diagnostic et au pronostic des défaillances observées sur les roulements et les engrenages. Nous les avons réadaptés pour convenir à l'étude des paramètres variables (tension, charge et/ou vitesse) qui peuvent apparaître dans les transmissions par courroie. Le principal intérêt de notre travail est le développement d’une procédure automatisée et efficace, permettant un suivi fiable des défaillances, dans les domaines d’analyses : modale, traditionnelle (temporelle, fréquentielle, spectrale), synchrone, temps-fréquence et surtout « cyclostationnaire » . Dans ce dernier domaine, avec des méthodes d’extraction de sources à partir d’un signal préalablement rééchantillonné, nous étudions spécifiquement les composantes périodique et aléatoire. Chaque type de défaut (variations au niveau de la tension, la charge et/ou la vitesse) a une signature que nous cherchons à distinguer avec des indicateurs de condition(temporels, fréquentiels et spectraux). Nous essayons de comparer les résultats expérimentaux à la théorie sur les transmissions par courroie. Grâce aux méthodes et algorithmes développés dans ce travail de thèse, nous apportons une contribution permettant de traiter un certain nombre de problèmes inhérents aux transmissions par courroies, à partir de leurs signaux expérimentaux acquis sur des accéléromètres, des jauges de contraintes et des codeurs optiques / In this PHD, we investigate experimental signals recorded from belt drives with a diagnosis aim of belt tension. Our research works present an exhaustive and thematic bibliography on theory and experimentation in belt drive to complete our insufficient knowledges in mechanical domain. We choosed a theoritical approach nearest real conditions of our belt drives bench. We included time fluctuaction in drive shaft speed and blet changes. Unfortunately, we could not resolve motion equations because existence of numerical limits. All conclusions will be used to understand and interprate experimental results after our signal processing numerical procedures. Our tools panel of numerical process comes from a comparative analysis extracted in several scientific documents and differents algorithms. They dedicate to surveillance, diagnosis and pronostic oriented toward bear and gear defaults. A adaptation in our belt case is necessary with variables parameters (tension, load and/or speed) affecting our case. In our automatic approach, we study several faults in analysis domains : modal, traditionnal (time, frequency, spectrum), synchronous, time-frequency and « cyclostationary » . In this last domain, we extract both comopnent (discret and random), after an previous resmapling operation applying to raw collected signal. Each falut type has a specific signature to discriminate with pertinent condition indications (time, frequency and spectrum domains). All results are discussed at the end of this PHD document. Our developped methods and algorithms are a contribution to process belt drives problems, from exprerimental signals recording with acceleromertes, constraint gauges and optical coders

Multilevel inverter technology has emerged recently as a very important alternative in the area of high-power medium-voltage energy control. Voltage operation above semiconductor device limits, lower common mode voltages, near sinusoidal outputs together with small dv/dt’s, are some of the characteristics that have made this power converters popular for industry and modern research. However, the existing solutions suffer from some inherent drawbacks like common mode voltage problem, DC-link capacitor voltage fluctuation etc. Cascaded multi-level inverter with open-end winding induction motor structure promises significant improvements for high power medium-voltage applications. This dissertation investigates such cascaded multi-level inverters for open-end winding induction motor drive with reduced switch count. Similar to the conventional two-level inverters, other multi-level inverters with PWM control generate alternating common mode voltage (CMV). The alternating common mode voltage coupled through the parasitic capacitors in the machine and results in excessive bearing current and shaft voltage. The unwanted shaft voltage may cross the limit of insulation breakdown voltage and cause motor failure. This alternating common mode voltage adds to the total leakage current through ground conductor and acts as a source of conducted EMI which can interfere with other electronic equipments around. As the number of level increase in the inverter, different voltage levels are made available by using DC-link capacitor banks, instead of using different isolated power supplies. The intermediate-circuit capacitor voltages which are not directly supplied by the power sources are inherently unstable and require a suitable control method for converter operation, preferably without influence on the load power factor. Apart from normal operation, the sudden fault conditions may occur in the system and it is necessary to implement the control strategy considering this condition also. A five-level inverter topology with cascaded power circuit structure is proposed in this dissertation with the strategy to eliminate the common mode voltage and also to maintain the balance in the DC-link capacitor voltages. The proposed scheme is based on a dual five-level inverter for open-end winding induction motor. The principle achievement of this work is the reduction of power circuit complexity in the five-level inverter compared to a previously proposed five-level inverter structure for open-end winding IM drive with common mode voltage elimination. The reduction in the number of power switching devices is achieved by sharing the two two-level inverters for both the inverter structures. The resultant inverter structure can produce a nine-level voltage vector structure with the presence of alternating common mode voltage. The inverter structure is formed by cascading conventional two-level inverters together with NPC three-level inverters. Thus it offers modular and simpler power bus structure. As the power circuit is realised by cascading conventional two-level and NPC three-level inverters the number of power diodes requirements also reduced compared to the conventional NPC five-level inverters. The present proposed structure is implemented for the open-end winding induction motor and the power circuit offers more number of switching state redundancies compared to any conventional five-level inverter. The inverter structure required half the DC-link voltage compared to the DC-link voltage required for the conventional five-level inverter structure for induction motor drive and this reduces the voltage stress on the individual power devices. The common mode voltage is eliminated by selecting only the switching states which do not generate any common mode voltage in pole voltages hence there will be no common mode voltage at the motor phase also. The technique of using the switching state selection for the common mode voltage elimination, cancels out the requirement of the filter for the same purpose. As the inverter output is achieved without the presence of common mode voltage, the dual inverter can be fed from the common DC-link sources, without generating any zero sequence current. Hence the proposed dual five-level inverter structure requires only four isolated DC supplies. The multi-level inverters supplied by single power supply, have inherent unbalance in the DC-link capacitor voltages. This unbalance in the DC-link capacitor voltages causes lower order harmonics at the inverter output, resulting in torque pulsation and increased voltage stress on the power switching devices. A five-level inverter with reduced power circuit complexity is proposed to achieve the dual task of eliminating common mode voltage and DC-link capacitor voltage balancing. The method includes the analysis of current through the DC-link capacitors, depending on the switching state selections. The conditions to maintain all the four DC-link capacitor voltages are analysed. In an ideal condition when there is no fault in the power circuit the balance in the capacitor voltages can be maintained by selecting switching states in consecutive intervals, which have opposite effect on the capacitor voltages. This is called the open loop control of DC-link capacitor voltage balancing, since the capacitor voltages are not sensed during the selection of the switching states. The switching states with zero common mode voltages are selected for the purpose of keeping the capacitor voltages in balanced condition during no fault condition. The use of any extra hardware is avoided. The proposed open loop control of DC-link capacitor voltage balancing is capable of keeping the DC-link capacitor voltages equal in the entire modulation region irrespective of the load powerfactor. The problem with the proposed open loop control strategy is that, it can not take any corrective action if there is any initial unbalance in the capacitor voltages or if any unbalance occurs in the capacitor voltages during operation of the circuit,. To get the corrective action in the capacitor voltages due occurrence of any fault in the circuit, the strategy is further improved and a closed loop control strategy for the DC-link capacitor voltages is established. All the possible fault conditions in the four capacitors are identified and the available switching states are effectively used for the corrective action in each fault condition. The strategy is implemented such a way that the voltage balancing can be achieved without affecting the output fundamental voltage. The proposed five-level inverter structure presented in this thesis is based on a previous work, where a five-level inverter structure is proposed for the open-end winding induction motor. In that previous work 48 switches are used for the realization of the power circuit. It is observed that all the available switching states in this previous work are not used for any of the performance requirement of CMV elimination or DC-link voltage balancing. So, in this proposed work, the power circuit is optimized by reducing some of the switches, keeping the performance of the inverter same as the power circuit proposed in the previous work. The five-level inverter proposed in this thesis used 36 switches and the number of switching states is also reduced. But, the available switching states are sufficient for the CMV elimination and DC-link capacitor voltage balancing. The advantage of the modular circuit structure of this proposed five-level inverter is further investigated and the inverter structure is modified to a seven-level inverter structure for the open end winding induction motor. The proposed power circuit of the seven-level inverter uses only 48 switches, which is less compared to any seven-level inverter structure for the open end winding induction motor with common mode voltage elimination. The power circuit is reduced by sharing four two-level inverters to both the individual seven-level inverters in both the sides of the of the open end winding induction motor. The cascaded structure eliminates the necessity of the power diodes as required by the conventional NPC multilevel inverters. The proposed seven-level inverter is capable of producing a thirteen-level voltage vector hexagonal structure with the presence of common mode voltage. The common mode voltage elimination is achieved by selecting only the switching states with zero common mode voltage from both the inverters and the combined inverter structure produce a seven-level voltage vector structure with zero common mode voltage. The switching frequency is also reduced for the seven-level inverter compared to the proposed five-level inverter. The advantage of this kind of power circuit structure is that the number of power diode requirement is same in both five-level and seven-level inverters. Since there is no common mode voltage in the output voltages, the dual seven-level inverter structure can be implemented with the common DC-link voltage sources for both the sides. Six isolated power supplies are sufficient for both the seven-level inverters. The available switching states in this proposed seven-level inverter are further analysed to implement the open loop and closed loop capacitor voltage balancing and this allow the power circuit to run with only three isolated DC supplies. All the proposed work presented in this thesis are initially simulated in SIMULINK toolbox and then implemented in a form of laboratory prototype. A 2.5KW open end winding induction motor is used for the implementation of these proposed works. But all these work general in nature and can be implemented for high power drive applications with proper device ratings.

Text in English with abstracts in English, Afrikaans and isiZulu / There has been considerable debate amongst feminist scholars as to whether the normalization of cosmetic surgery positively impacts women, empowers women by promoting agency and choice (Gimlin 2002, Kuczynski 2006), or oppresses women by propagating patriarchal ideologies that confine women’s bodies and consequently inhibit their voice (Blum 2003, Blood 2005, Heinricy 2006, Clarke and Griffin 2007, Tait, 2007). Rather than entering this debate my argument proceeds from a premise that the normalization of cosmetic surgery is a form of implicit and exclusive violence. Using a selection of post‐structuralist, feminist, and psychoanalytic theories, I analyze the manner in which this form of violence confines women’s bodies and structures the psyche. Using Jacques Lacan, Judith Butler, and Michel Foucault’s argument on pastoral power, I deconstruct the formation of the normalized self, the conscience, and the act of confession as it translates in the context of the cosmetic surgical body itself. Furthermore, I highlight liberal feminism’s role in this form of oppression. In so doing, I theoretically show the continual and effective functioning of pastoral power in the context of an individualization technique that oppresses women in the second decade of the twenty‐first century. I argue that the normalization of cosmetic surgery provokes a silencing of woman’s voices, an exploitation and oppression of the individual’s psyche, and an invalidation of the living body by a less visible, less explicit, mode of incarceration that is concealed by an aesthetic and moral veil. It is in this context that I present a counter discourse to the oppression that underlies the normalizing discourses promoted by the cosmetic surgical industry, a destabilization of patriarchal norms embedded within cosmetic surgical discourses, and a theoretical reconstruction that involves an inscription of what I refer to as an authentic feminist voice in contemporary consumer culture – a mode of intimate unconscious insurgence. I advocate a return to Julia Kristeva’s theory and the intimate revolt promoted by her ethical approach. Furthermore, I present a voice that demonstrates an intimate revolt – a voice that challenges patriarchal norms and is not exclusively confined by the mechanisms of normalization that shape the twenty‐first century woman with emphasis on the cosmetic surgical industry and its superincumbent discourses – the South African poet Antjie Krog. It is Krog’s skillfully structured poetic texts that facilitate my theoretical reconstruction. Applying Kristeva’s theory on semanalysis, I theoretically show that Krog’s work fabricates an excess to the confines of the law of the Father and the mechanisms of normalization itself. In addition, I present an “originary attachment” as an adaption of Kristeva’s argument on the chora and my proposal of an “originary ideal” challenges Kristeva’s emphasis on phonetic grams in the context of that which underlies the realm of the paternal metaphor. Using Louise Viljoen’s analysis of Krog’s work and Bridget Garnham’s research on emerging designer cosmetic surgical discourses as support, I then present Krog’s poetic texts as a counter discourse to the “moral” cosmetic surgical discourses that exploit the ageing individual in the second decade of the twenty‐first century. In addition, applying Kristeva’s theory on paragrams to Krog’s poetic text(s), I present a destabilization of the patriarchal norms implicit within cosmetic surgical discourses. Furthermore, I extend Kristeva’s theory on the principle of negativity to present a re‐translation of the act‐of‐confession in Krog’s poetic text(s), an extension of Foucault’s pastoral power and Butler’s argument on the exclusivity of normalization, and a reclamation of her ageing body in Verweersrkrif/Body Bereft (Krog 2006). / Feministiese geleerdes voer al geruime tyd 'n warm debat oor die kwessie of die normalisering van kosmetiese chirurgie vroue positief beïnvloed, vroue bemagtig deurdat dit volmag en keuse vir hulle in die hand werk (Gimlin 2002; Kuczynski 2006), of vroue onderdruk deurdat dit patriargale ideologieë voorstaan wat die vroueliggaam inperk en gevolglik die vrou inhibeer om haar stem te laat hoor (Blood 2005; Blum 2005; Clarke en Griffin 2007; Heinricy 2006; Tait 2007). In plaas daarvan om by hierdie debat betrokke te raak, gaan ek van die veronderstelling uit dat die normalisering van kosmetiese chirurgie 'n vorm van implisiete en eksklusiewe geweld is. Aan die hand van post-strukturalistiese, feministiese en psigoanalitiese teorieë ontleed ek die manier waarop hierdie vorm van geweld vroue se liggaam onderwerp en hul psige vorm. Ek dekonstrueer die vorming van die genormaliseerde self, die bewussyn en die daad van belydenis, soos dit in die konteks oorgebring word, aan die hand van Jacques Lacan, Judith Butler en Michel Foucault se beskouings van herderlike oftewel pastorale mag. Hierbenewens onderstreep ek die rol wat liberale feminisme in hierdie vorm van onderwerping speel. Sodoende demonstreer ek teoreties hoe die voortdurende en effektiewe funksionering van pastorale mag in die konteks van ’n individualiseringstegniek vroue in die tweede dekade van die een-en-twintigste eeu onderdruk. Ek maak die aanname dat die normalisering van kosmetiese chirurgie daartoe bydra dat vroue die swye opgelê word, die individu se psige uitgebuit en onderdruk word en die lewende liggaam ontkragtig word deur middel van ’n inkerkering wat minder sigbaar en minder eksplisiet is en agter ’n estetiese en morele sluier verdoesel word. In hierdie konteks bied ek ’n teendiskoers aan vir die onderwerping wat onderliggend is aan die normaliseringsdiskoerse wat die kosmetiesechirurgiebedryf ondersteun, en ek bepleit dat die patriargale norme wat in diskoerse oor kosmetiese chirurgie vassit, gedestabiliseer word. Ek demonstreer verder ’n teoretiese rekonstruksie wat ’n inskripsie insluit van wat ek ’n geloofwaardige feministiese stem in die eietydse verbruikerskultuur noem – ’n modus van intieme, onbewuste opstandigheid. Ek bepleit 'n terugkeer na Julia Kristeva se teorie en die intieme oproer wat deur haar etiese benadering voorgestaan word. Afgesien hiervan stel ek ’n stem voor wat ’n intieme opstand demonstreer – ’n stem wat patriargale norme uitdaag en nie uitsluitlik onderdruk word deur die normaliseringsmeganismes wat vorm gee aan die vrou van die een-entwintigste eeu nie, waar die klem op die kosmetiesechirurgiebedryf en die boliggende diskoerse daarvan val – Antjie Krog, Suid-Afrikaanse digter. Dit is juis Krog se kunstig gestruktureerde digterlike tekste wat my teoretiese rekonstruksie fasiliteer. Aan die hand van Kristeva se teorie oor semanalise toon ek teoreties dat Krog se werk ’n ruimte daarstel wat "uitstyg" bo die grense wat die wet van die Vader en die normaliseringsmeganismes stel. Hierbenewens stel ek ’n "originêre gehegtheid" as aanpassing van Kristeva se beskouing van die chora voor, en my voorstel van ’n "originêre ideaal" daag Kristeva se opvating oor paragramme uit in die konteks van dit wat ten grondslag lê aan die gebied van die paternalistiese metafoor. Op grond van Louise Viljoen se ontleding van Krog se werk en Bridget Garnham se navorsing oor opkomende diskoerse oor ontwerpers- kosmetiese chirurgie bied ek Krog se digterlike tekste aan as ’n teendiskoers vir die "morele" diskoerse oor kosmetiese chirurgie wat die verouderende individu in die tweede dekade van die een-en-twintigste eeu uitbuit. Daarby, deur Kristeva se teorie oor paragramme op Krog se digterlike teks(te) toe te pas, demonstreer ek 'n destabilisering van die patriargale norme wat implisiet in diskoerse oor kosmetiese chirurgie teenwoordig is. Hierbenewens brei ek Kristeva se teorie oor die negatiwiteitsbeginsel uit deur middel van ’n heroorsetting van die belydenisdaad in Krog se digwerk(e), ’n uitbreiding van Foucault se pastorale mag en Butler se opvatting oor die eksklusiwiteit van normalisering, en ’n opeising van Krog se verouderende liggaam in Verweerskrif/Body Bereft (Krog 2006). / Sekubekhona izingxoxo-mpikiswano eziningi kwizifundiswa zama-feminist ukuthi ngabe ukwenza isurgery yohlinzo olungajulile ukuzishintsha ukubukeka ngokwemvelo (cosmetic plastic surgery) kunomphumela omuhle yini kwabesimame, ngabe kuhlinzeka ngamandla kwabesimame ngokuphakamisela phezulu ukuthi umuntu azenzele akufunayo kanye nokuzikhethela (Grimlin 2002, Kuczynski 2006) noma kuyinto ecindezela abesimame ngokuqhubela phambili indlela nama-idiyoloji abekwa ngabesilisa ukuthi imizimba yabesimame kumele ibukeke kanjani, kanti lokhu kucindezela izwi labesimame (Blum 2003, Blood 2005, Heinricy 2006, Clarke and Griffin 2007, Tait, 2007). Kunokuthi iphuzu nami ngingenele kule ngxoxo-mpikiswano, elami iphuzu lona liqhubeka ukusukela kwisimo sokuthi ukwamukela uhlujzo olungajulile lokuzitshintsha ukubukeka kwabesimame (cosmetic surgery) kuyindlela yodlame olungaqondile ngqo kanye nolukhipha inyumbazane abesimame. Ngokusebenzisa amathiyori epost-structuralist, awe-feminist kanye nawepsychoanalytical, ngihlaziya indlela le nhlobo yalolu dlame ecindezela ngayo imizimba yabesimame kanye nokuhlela indlela okumele bacabange nokuzibona ngayo. Ngokusebenzisa iphuzu likaJacques Lacan, Judith Buttle kanye noMichel Foucault lamandla okukhokhela ngokomoya, ngiqhaqha indlela okubumbeka ngayo isithombe sokuzibona, unembeza kanye nomoya wokuhlambulula ngokuzidalula (confession) lapho kubhekwa izinto ngaphansi kwesimo somzimba wokuhlinzwa okungajulile ukuzishintsha ukubukeka ngokwakho. Nangaphezu kwalokho, ngigqamisa indima ye-liberal feminism ngokwayo kule nhlobo yencindezelo. Ngokwenza lokho, ngikhombisa ngokwethiyori ukuqhubeka nokusebenza kwamandla esikhokhelo ngokomoya ngaphansi kwethekniki yokuzazi komuntu eyedwa okucindezela abesimame kwiminyaka elishumi yesibili, yesenshuri yamashumi amabili nanye . Ngiqhubela phambili iphuzu lokuthi ukwenziwa kohlinzo olungajulile lokuzishintsha ukubukeka kuqala umoya wokucindezela izwi labesimame, ukuxhashazwa kwabo, kanye nendlela umuntu azibona ngayo ngokwengqondo, kanye nokucindezela umzimba ophilayo ngezindlela ezingazibonakalisi obala, ezifihlekile, indlela yokubopha efihlwa yindlela yokubukeka kanye nokwembozwa umoya. Kungaphansi kwalesi simo lapho ngethula khona i-discourse yencindezelo eyenza ukuthi imboni yohlinzo olungajulile ukuzishintsha ukubukeka kwabesimame kube yinto ephakanyiswayo nokubonwa iyinhle, ukuphazamiseka kwama-norm endlela yengcindezi yabesilisa, ngaphansi kwama-discourse okuhlinzwa okungajulile ukushintsha ukubukeka, kanye nokwakha ithiyori ebandakanya ukubona izinto ngendlela ethize, engikuchaza njengezwi okuyilo elifanele le-feminism, kwisimo sosiko esiphila ngaphansi kwaso samanje - okuyindlela abantu abazibuka ngayo ezingqondweni ngendlela engekho obala. Ngigcizelela ukubuyela kwithiyori kaKristeva, kanye nokuthi abantu babhoke indlobana ngezindlela eziphansi, okuyinto ayiphakamisayo yenkambiso yokwazi okulungile nokungalunganga (ethical approach). Naphezu kwalokho, ngiveza izwi elibonisa ukubhoka indlobana kwabesimame ngendlela engekho sobala - izwi elifaka inselele kuma-norm okubhozomelwa ngumqondo wokulawula kwabesilisa, kanti futhi leli zwi aligcinanga nje kuphela umumo wabesimame ngendlela ejwayelekile njengowesimame wesenshuri yamashumi amabili-nanye ngokugcizelela kwimboni yohlinzo olungajulile lokuzishintsha ukubukeka, kanye nendlela lokhu okuyisihibe ngayo – ngokusho kukasonkondlo waseNingizimu Afrika, u-Antjie Krog. Imibhalo yezinkondlo zikaKrog ezinobungcweti yiyo eyenze ukwakha kwami kabusha ithiyori. Ngokusebenzisa ithiyori kaKristeva ye-semanalysis, ngibonisa ngokwethiyori ukuthi umsebenzi kaKrog uqambe okweqele ngaleya kwizihibe zomthetho kubaba kanye nezindlela zokwenza izinto zibukeke ngendlela evamile noma zingavamile. Nangaphezu kwalokho, ngifakela i-"originary attachment" njengokwenza ukuthi kube kwesinye isimo, iphuzu likaKristeva ku-chora kanti isiphakamiso sami se-"originary ideal" sifaka inselele kusigcizelelo sikaKristeva ngamagremu efonethiki ngaphansi kwesimo esigcizelela umfanekiso ngasohlangothini lobaba. Ngokusebenzisa ukuhlaziya kukaLouise Viljoen kumsebenzi kaKrog kanye nocwaningo lukaBridget Garnham ngokuvela kwama-discourse ohlinzo olungajulile ukuzishintsha ukubukeka njengesisekelo, ngase ngethula imibhalo yezinkondlo zikaKrog njenge-discourse yokuphikisa ama-discourse e-"moral" yama-discourse ohlinzo olungajulile lokuzishintsha ukubukeka, elixhaphaza abantu abagugayo ngeminyaka eyishumi yesibili kwisenshuri yamashumi amabili-nanye. Naphezu kwalokho, ngisebenzise ithiyori kaKristeva kumapharagramu kwimibhalo yezinkondlo zikaKrog, ngaphazamisa imibono yokuphatha kwabesilisa equkethwe kuma-discourse ohlinzo ulungajulile ukuzishintsha ukubukeka. Ukuqhubekela phambili, nginwebe ithiyori kaKristeva ngesimiso se-negativity ukwethula ukuhumusha kabusha umoya wokuzihlambulula ngokuzidalula otholakala kwizinkondlozikaKrog, ukuwukunweba amandla umbono kaFaucault wamandla okuthi abantu bazibone ngenye indlela kanye nephuzu likaButler wlkuthi into engavamile engaphandle ibonwe njengento efanele, kanye nokwamukela umzimba ogugayo kwinkondlo ye- Verweerskrif/Body Bereft (Krog 2006). / English Studies / D. Litt. et Phil.(Theory of Literature)

This dissertation investigates the correlation between semiotic theory and the way that gendered subjectivity is represented in contemporary South African art. The phenomenon of signification is central to the semiotic theories of the Bulgarian semiotician and psychoanalyst Julia Kristeva. Semiotics can be described as the science of the sign that considers the way in which artists express their personal experience in art making. In this investigation I refer mainly to women's artworks, although the concept of gendered subjectivity in the work of male artists is also discussed. This particular research investigates the symbolic relations of culture in gender terms, that explores the apparent contradictions of subjectivity inherent in capitalist patriarchal society. / Art History, Visual Arts and Music / M.A. (Visual Arts)

Resumo: Este trabalho apresenta uma nova proposta para sistema de refrigeração com controle dinâmico de temperatura, operando com estrutura de compressor aberto, acionado por motor de indução trifásico com velocidade variável, e estágio de entrada retificador com correção ativa do fator de potência. O estágio de entrada é composto por um retificador Boost monofásico com elevado fator de potência, com duas células entrelaçadas, operando no modo de condução crítica, empregando técnica de comutação não dissipativa e controlado por dispositivo FPGA, associado a um estágio de saída inversor de dois níveis convencional trifásico à IGBT, o qual é controlado por um Processador Digital de Sinais (DSP - Digital Signal Processor). A técnica de comutação não dissipativa para o estágio de entrada é baseada em células ZCS (Zero-current-switching). As principais características do retificador incluem a redução da ondulação da corrente de entrada, redução da ondulação da tensão de saída retificada, utilização de componentes com reduzidos esforços, reduzido volume do filtro de entrada para Interferências Eletromagnéticas (EMI - Electromagnetic Interference), elevado Fator de Potência (FP) e reduzida Distorção Harmônica Total (DHT) da corrente de entrada, atendendo os limites da norma IEC61000-3-2. O controle digital para o estágio de saída inversor foi desenvolvido usando duas diferentes técnicas, incluindo a técnica convencional controle escalar Volts/Hertz (V/Hz) e o controle Vetorial com Orientação pelo Fluxo do estator, com o propósito de verificar a aplicabilidade e a performance dos controles digitais propostos, para o controle contínuo da temperatura, aplicados a um protótipo de sistema de refrigeração. / Abstract: This work presents a new proposal for refrigeration systems with dynamic control of temperature, working with structure of open compressor, driving a three-phase induction motor with variable speed, and input rectifier with active power factor correction. The proposed system is composed of a single-phase high-power-factor boost rectifier, with two cells in interleaved connection, operating in critical conduction mode, and employing a softswitching technique, controlled by a Field Programmable Gate Array (FPGA), associated with a conventional three-phase IGBT bridge inverter (VSI - Voltage Source Inverter), controlled by a Digital Signal Processor (DSP). The soft-switching technique for the input stage is based on zero-current-switching (ZCS) cells. The rectifier’s features include reduction in input current ripple, reduction in output voltage ripple, use of low stress devices, low volume for the EMI input filter, high input power factor (PF), and low total harmonic distortion (THD) in the input current, in compliance with the IEC61000-3-2 standards. The digital controller for the output stage inverter has been developed using two different techniques, the conventional Voltage-Frequency control (scalar V/Hz control), and a simplified stator oriented vector control, in order to verify the feasibility and performance of the proposed digital controls, for continuous temperature control, applied at a refrigerator prototype. / Orientador: Carlos Alberto Canesin / Coorientador: Flávio Alessandro Serrão Gonçalves / Banca: Fabio Toshiaki Wakabayashi / Banca: João Onofre Pereira Pinto / Mestre

The aim of this thesis is a complex design of the spotting press with a nominal force of 500 kN, which is intended for mating of the both halves of pressing tool for the automotive industry. The press ram is fitted with a hydraulic mechanism which allows the upper clamping board to be tilted in range of 0° -180° and removed from the working space of the press along a profile track. The lower clamping board is a part of moving bolster, which is equipped with a mechanism for lifting and centring. The concept of motion screws is used to drive the ram. Motion screws are mounted in a multiple-part frame and driven by servomotors. The thesis contains background research of the issue, solutions of the main design nodes of the press including calculations, detailed 3D model of the device and partial drawing documentation.