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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Moloi ga a na mmala (a witch has no colour) : a socio-religious study of witchcraft accusations in the Northern Province of South Africa

Kgatla, Selaelo Thias 11 1900 (has links)
Witchcraft discourse in South Africa has increasingly permeated all social structures, thereby becoming a real threat to the process of reconstruction and development. The neglect of witchcraft accusations and their resultant consequences can cause the country to lose all it gained as a result of the liberation struggle. In this study I examine the historical developments of witchcraft accusations around the world in general, and in South Africa in particular as well as the threats they pose to society. I analyse five broad areas: 1) The inborn h tendency to scapegoat; jealousy; and the role religion plays in the escalation of these problems; 2) The African world-view and its consequences on interpersonal relationships; 3) Colonial and missionary attempts to suppress the African world-view; 4) Ways and means of containing the conflicts arising from the witchcraft problem; and 5) Summary of findings. The research was occasioned by the untold suffering victims of witchcraft accusations have to undergo in the three Northern Provinces of South Africa. Because of the cruelty and misery such accusations cause the poor people of these rural provinces urgent attention is needed to contain them, especially since such accusations have not diminished despite all governmental efforts to curtail them. At the centre of witchcraft accusations there are stress, hatred, vindictiveness, and aspirations to become famous. The fear that one may be victimised by either being accused of witchcraft or being bewitched is very real even today. The relevance of the study is apparent when one considers the feelings of helplessness that paralyses the opponent of this carnage, such as government and the churches. A number of resources should thus be employed to counter would be put into it. This threat which is aggravated by the abject poverty prevalent in the rural communities of the three Provinces. The prevailing conditions of abject poverty play a definite role in the creation, promotion and escalation of the scourge. Policy makers should therefore have clear grasp of the extent to which poverty has influence on society in any effort to contain witchcraft accusations. I conclude the study by ~ecommending transformational paths to the Government, NonGovernmental Organisations and other Community Leaders to follow in attending to improve the lot of the poor. This is done by highlighting ten findings that emerged during the study. The findings were the result of analyses of archival records, literature and case studies on witchcraft accusations. Because the subject of witchcraft is so wide and emotive I have employed several sociological and anthropological theories to cover as wide a field as possible. The incorporation of so many theoretical approaches into the study presents on interpretive and analytical explanation of the causes, effects and containment of witchcraft accusations. The overall conclusion is encapsulated by the title of the study Moloi ga a na mmala (A witch has no colour). A witch remains unidentifiable, but witch-hunters and sniffers know how to identify their witches. Although the process remains paradoxical, it is practised on a daily basis. / Religious Studies and Arabic / D.Litt. et Phil. (Religious Studies)
402

Beitrag zum dielektrischen Verhalten des Öl-Papier-Isoliersystems unter Gleich- und Mischspannungsbelastung

Gabler, Tobias 23 November 2021 (has links)
Stromrichtertransformatoren der Hochspannungsgleichstromübertragung bilden das Bindeglied zwischen Gleichspannungs- und Drehstromsystem. Um den ausfallsicheren Betrieb über die gesamte Lebensdauer zu gewährleisten, muss deren Öl-Papier-Isoliersystem entsprechend dimensioniert werden. Eine optimale Dimensionierung setzt ein detailliertes Verständnis über die Beanspruchung des Isoliersystems sowie deren zuverlässige Modellierung sowohl unter Betriebsspannung als auch bei den überlagerten, transienten Überspannungen voraus. Im Rahmen dieser Arbeit wird daher das dielektrische Verhalten des Öl-Papier-Isoliersystems in Anlehnung an dielektrische Prüfungen sowohl unter Gleichspannungsbelastung als auch einer zusammengesetzten Spannungsbelastung aus einer Gleich- und einer Blitzstoßspannung (einer sog. Mischspannungsbelastung) untersucht. Der Vergleich von numerischen Berechnungen auf Grundlage eines ladungsträgerbasierten Ansatzes nach Poisson-Nernst-Planck (PNP) mit Durchschlagexperimenten gibt dabei Aufschluss über die Beanspruchung des Öl-Papier-Isoliersystems. Weiterhin wird gezeigt, dass der in den etablierten, resistiv-kapazitiven Berechnungsmodellen vernachlässigte Ladungsträgereinfluss in Bezug auf die Beanspruchung des Isoliersystems unzureichende Ergebnisse zur Folge hat und demnach zwingend zu berücksichtigen ist. Die an realitätsnahen, Öl-Papier-isolierten Anordnungen erzielten Ergebnisse zeigen nicht nur den Einfluss der an Grenzflächen oder im Papier akkumulierten Ladungsträger auf die Beanspruchung des Isoliersystems. Ebenso werden die Annahmen des ladungsträgerbasierten Ansatzes und die Berechnungsergebnisse des PNP-Modells qualitativ bestätigt. Infolge der Ladungsakkumulation im Papier tritt die höchste Beanspruchung im Ölspalt und nicht im Papier auf. Öl-Papier-isolierte Anordnungen werden somit geringer beansprucht, als eine Strömungsfeldberechnung vermuten lässt. Dies widerspricht den Annahmen der etablierten Berechnungsmodelle und wird im Weiteren durch Polaritätseffekte an homogenen, aber unsymmetrischen, papierisolierten Elektrodenanordnungen oder durch den nachweisbaren Einfluss des Ölvolumens im Prüfgefäß auf die Beanspruchung einer Anordnung verdeutlicht. Unter Mischspannungsbelastung wird weiterhin gezeigt, dass eine Überlagerung der Gleichspannung und damit auch der Polaritätswechsel keine höhere Beanspruchung des Isoliersystems im Vergleich zur reinen Gleichspannungsbelastung zur Folge hat. Die etablierten, resistiv-kapazitiven Modelle ließen jedoch den Polaritätswechsel als kritischste Beanspruchung vermuten. Somit wird nicht nur die Anwendbarkeit der ladungsträgerbasierten PNP-Modellierung an Öl-Papier-Isolieranordnungen qualitativ verifiziert. Ebenso wird demonstriert, dass die stark vereinfachten Annahmen der etablierten Berechnungsmodelle die Beanspruchungen unter Gleich- und der untersuchten Mischspannungsbelastung nicht abbilden können. Der Einsatz klassischer Strömungsfeldberechnungen zur Nachbildung der Beanspruchung des Öl-Papier-Isoliersystems unter Gleichspannungsbelastung entspricht damit nicht mehr dem Stand der Forschung. / Converter transformers of HVDC transmission systems connect HVDC and HVAC systems. To ensure a reliable operation during the entire lifetime, their oil-paper-insulation system must be designed appropriately. An optimized dielectric design demands a fundamental understanding of the dielectric stresses as well as a reliable modeling of the insulation system both under operating voltages and under superimposed, transient overvoltages. Hence, in this work the dielectric behavior of the oil-paper-insulation system is investigated. Based on dielectric tests the investigations are performed under DC voltage stress and a composite voltage stress of a DC voltage in stationary conditions superimposed by a lightning impulse voltage. The comparison of numerical calculations using a charge-carrier-based approach according to Poisson-Nernst-Planck (PNP) with breakdown experiments clarifies the dielectric stress of the oil-paper-insulation system. Furthermore, the comparison with results determined by the established, resistive-capacitive calculation models shows that it is mandatory to take the influence of the charge carrier accumulation into account. The presented results, which were obtained at oil-paper-insulated arrangements which represent the dielectic stress of real arrangements, show the influence of the charge carriers accumulating at interfaces or in the paper insulationon on the dielectric stress. The results confirm the calculations and the assumptions according to the charge-carrier-based model as well. Due to the charge carrier accumulation, the highest dielectric stress occurs in the mineral oil and not in the paper insulation. In contrast, the findings obtained assuming an ohmic conductivity would results in a higher dielectric stress of the oil-paperinsulated arrangements. Furthermore, polarity effects in homogeneous but asymmetrical, paper-insulated electrode arrangements or the influence of the surrounding oil in the test vessel demonstrate the effects of the charge carriers. Under composite voltage stresses it is also shown, that the applied superimposed voltage as well as the fast polarity reversal does not lead to a higher dielectric stress of the arrangements compared to the pure DC voltage stress. Commonly used calculation models would determine higher stresses due to the fast polarity reversal instead. Consequently, the applicability of the charge-carrier-based PNP calculation model is verified qualitatively in the presented investigations. Furthermore, it is demonstrated that the simplified assumptions of the commonly used calculation models cannot simulate the dielectric stresses under DC voltage stress and under the investigated superimposed voltage stresses. Hence, the determination of the dielectric stresses of oil-paper-insulation systems under DC voltage stress according to the commonly used calculation models assuming an ohmic conductivity does not correspond to the current state of research.
403

Mateřská školka v Brně / Nursery school, Brno

Sedláček, Jan January 2014 (has links)
The subject of this work is the solution of a new building of nursery school in the village of Ivanovice. It is a cellarless, two-storey building for 40 childern. The floor plan is „L“ shaped with orientation of the classes to the south and west which provide enough rate (amount) of insolation which support good mood and development of the childern. The object is situated in medium sloping land mainly in the area of familly and residential houses. The main entrance to the building is situated on the south from where si access road to the object too. Comfort parking is provided by ten parking places, one is determined for disabled people. The lighting and ventilation of all rooms is provided by windows. Roofing is solved using of wooden truss in combination with single casing roof.
404

Zum Entladungsprozess der Spitze-Spitze-Elektrodenanordnung bei standardisierter und oszillierender Blitzspannung

Gürlek, Akif 02 March 2021 (has links)
Diese Dissertation widmet sich der Erfassung, Identifikation und Beschreibung von Entladungsprozessen, die an Überschlägen bei Blitzspannung auftreten. Es wird ein Messsystem entwickelt, welches die elektrischen und optischen Parameter der Entladungsprozesse an der Spitze-Spitze-Elektrodenanordnung bei standardisierter und oszillierender Blitzspannung mit hoher Empfindlichkeit und Synchronisationsgenauigkeit aufzeichnet. Mithilfe der Strommessungen und der fotografischen Aufzeichnungen von Entladungen können drei Phasen des Durchschlagprozesses identifiziert werden: In der Reihenfolge ihres Auftretens handelt es sich um die Streamerphase, die Kanalübergangsphase und die Kanalbildungsphase. Diese Phasen werden für die standardisierte und oszillierende Blitzspannung aufgezeigt, wobei Gemeinsamkeiten und Unterschiede herausgestellt werden. Anhand von statistischen Beschreibungen des Durchschlagverhaltens und des Entladungsverhaltens werden daraufhin Abhängigkeiten in den Entladungsprozessen abgeleitet. / This thesis is dedicated to the acquisition, identification and description of discharge processes, which occur under lightning impulse voltage. A measuring system has been developed that records the electrical and optical parameters of the discharge processes with a high sensitivity and synchronization accuracy on a rod-rod electrode arrangement under standardised and oscillated lightning impulse voltage. With the current measurements and the photographic records of discharges, three phases of the breakdown process can be identified. In order of their occurrence these are the streamer phase, the channel transition phase and the channel formation phase. These phases are shown for the standardised and oscillated lightning impulse voltage, whereby similarities and differences are presented in detail. Using statistical descriptions of the breakdown and the discharge behaviour, dependencies in the discharge process will be derived.
405

電気鉄道き電システムの雷対策に向けた実測およびシミュレーション技術に関する一研究 / デンキ テツドウ キデン システム ノ カミナリ タイサク ニ ムケタ ジッソク オヨビ シミュレーション ギジュツ ニカンスル イチケンキュウ

田中 弘毅, Hiroki Tanaka 22 March 2017 (has links)
電気鉄道の安全安定輸送を確保するため,雷害防止が求められている。本論文では,電気鉄道設備の雷サージ特性実測を行い,接地インピーダンス特性を雷サージの視点から検討した。さらに,電力系統解析技術を応用して鉄道特有機器の回路解析モデルを開発し,その精度を実測で確認し,鉄道設備雷電流侵入時の応答を実測および計算結果より明らかにした。これらの成果は,電気鉄道の設計・保守・解析に十分に生かすことが可能である。 / Lightning protection is required to ensure safe and stable electric railway transportation. In this thesis, the lightning surge characteristics of the facilities in electric railway systems were measured. The characteristic of earthing impedance was also investigated from the viewpoint of lightning surge. In addition, some numerical models of railway specific apparatuses for circuit analysis method were developed by applying simulation technology for power system and confirmed their accuracies by actual measurements. The responses to lightning currents invaded into the facilities were clarified by the measured and calculated results. These results can be fully utilized in the design, maintenance and analysis of electric railway systems. / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
406

Cinema ao vivo e experiências audiovisuais em tempo real / -

Molina Júnior, Jair Sanches 15 September 2017 (has links)
Refletir sobre as experiências com imagens e sons em tempo real é pensar em uma ampla gama de possibilidades e experiências pela humanidade, desde os tempos mais remotos. Pelo fato dessas experiências audiovisuais em tempo real serem numerosas no tempo e no espaço, e já amplamente citada em diferentes estudos, esta apresentação tem por objetivo realizar um recorte mais restrito às experiências audiovisuais em tempo real no campo cinematográfico contemporâneo: uma arte, meio e processo em expansão que culmina na existência de um fenômeno semiótico, realizado principalmente através de modos experimentais com a presença do(s) autor(es) concebendo a experiência audiovisual, conjuntamente ao aparato tecnológico e ao público, todos participantes da criação e exibição da obra audiovisual no mesmo tempo em que ela ocorre, em transmissão direta para a tela de cinema, monitores, telas digitais ou espaços arquitetônicos. Com base em obras audiovisuais realizadas entre 2007 a 2017 desenvolveremos uma reflexão e análise das poéticas e técnicas das experiências audiovisuais em tempo real, de maneira a compreender com um olhar mais atento as possibilidades criativas e contribuir com a reflexão sobre estes formatos do audiovisual contemporâneo, cujos meios e processos estão em contínua expansão de suas fronteiras. Em estética do cinema, esta pesquisa segue em continuidade aos estudos e práticas do cinema experimental e em sua vértice ao cinema expandido. / Reflecting about real-time imagery and sounds experiences is thinking about a wide range of possibilities and experiences for humanity, from the earliest times. Because the real-time audiovisual experiences are numerous in time and space, and already widely quoted in different studies, this presentation aims to make a more restricted cut-off to real-time audiovisual experiences in the contemporary cinematographic field: an art, medium and an expanding process that culminates in the existence of a semiotic phenomenon, performed mainly through experimental modes with the presence of the author(s) directing the audiovisual experience in real-time, together with the technological apparatus, the cast, and the public, all participants in the creation and exhibition of the audiovisual work at the same time as it occurs, in direct transmission to the cinema screen, monitors, digital screens or architectural spaces. Based on audiovisual works carried out between 2007 and 2017 we will develop a reflection and analysis of the poetics and techniques of audiovisual experiences in real-time, in order to understand with a closer look the creatives possibilities in live cinema and contribute with reflection on these forms of the contemporary audiovisual, whose means and processes are in continuous expansion of its borders. In aesthetics of the cinema, this research follows in continuity to the studies and practices of the experimental cinema, and in its vertex to the expanded cinema.
407

Cinema ao vivo e experiências audiovisuais em tempo real / -

Jair Sanches Molina Júnior 15 September 2017 (has links)
Refletir sobre as experiências com imagens e sons em tempo real é pensar em uma ampla gama de possibilidades e experiências pela humanidade, desde os tempos mais remotos. Pelo fato dessas experiências audiovisuais em tempo real serem numerosas no tempo e no espaço, e já amplamente citada em diferentes estudos, esta apresentação tem por objetivo realizar um recorte mais restrito às experiências audiovisuais em tempo real no campo cinematográfico contemporâneo: uma arte, meio e processo em expansão que culmina na existência de um fenômeno semiótico, realizado principalmente através de modos experimentais com a presença do(s) autor(es) concebendo a experiência audiovisual, conjuntamente ao aparato tecnológico e ao público, todos participantes da criação e exibição da obra audiovisual no mesmo tempo em que ela ocorre, em transmissão direta para a tela de cinema, monitores, telas digitais ou espaços arquitetônicos. Com base em obras audiovisuais realizadas entre 2007 a 2017 desenvolveremos uma reflexão e análise das poéticas e técnicas das experiências audiovisuais em tempo real, de maneira a compreender com um olhar mais atento as possibilidades criativas e contribuir com a reflexão sobre estes formatos do audiovisual contemporâneo, cujos meios e processos estão em contínua expansão de suas fronteiras. Em estética do cinema, esta pesquisa segue em continuidade aos estudos e práticas do cinema experimental e em sua vértice ao cinema expandido. / Reflecting about real-time imagery and sounds experiences is thinking about a wide range of possibilities and experiences for humanity, from the earliest times. Because the real-time audiovisual experiences are numerous in time and space, and already widely quoted in different studies, this presentation aims to make a more restricted cut-off to real-time audiovisual experiences in the contemporary cinematographic field: an art, medium and an expanding process that culminates in the existence of a semiotic phenomenon, performed mainly through experimental modes with the presence of the author(s) directing the audiovisual experience in real-time, together with the technological apparatus, the cast, and the public, all participants in the creation and exhibition of the audiovisual work at the same time as it occurs, in direct transmission to the cinema screen, monitors, digital screens or architectural spaces. Based on audiovisual works carried out between 2007 and 2017 we will develop a reflection and analysis of the poetics and techniques of audiovisual experiences in real-time, in order to understand with a closer look the creatives possibilities in live cinema and contribute with reflection on these forms of the contemporary audiovisual, whose means and processes are in continuous expansion of its borders. In aesthetics of the cinema, this research follows in continuity to the studies and practices of the experimental cinema, and in its vertex to the expanded cinema.

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