The totem pole PFC suffers from the Mosfet body diode reverse recovery issue which limits this topology adopted in the CCM high power condition. As the ultra-fast IGBT which is capable of providing 100 kHz switching frequency is available in the market, it is possible to apply the totem pole PFC in CCM high power condition. The thesis provides a method by implementing the ultra-fast IGBT and SiC diode to replace the MOSFET in this topology. To verify the method, a universal CCM totem pole PFC is designed and tested. The design adopts the ADP1048 programmable digital PFC controller by adding external logic gate for totem-pole PFC. ADP1048 greatly simplifies the design process and satisfies the design requirements. The experiment results verify that the totem-pole PFC can be applied into CCM high power condition by using the method. The DC output voltage is well regulated. The power factor is higher than 0.98 when the load is above 400W. The measured efficiency can achieve up to 96.8% at low line and 98.2% at high line condition with switching frequency 80 kHz. / Master of Science

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A análise descrita nesta dissertação tem como objetivo a medida da seção de choque difrativa d&#963;/d|t| à energia no sistema do centro de massa de &#8730;s = 8 TeV. Os eventos usados para obter a seção de choque difrativa foram selecionados para processos de difração simples com um próton espalhado na região frontal e na região cinemática de 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, usando os dados em comum obtidos em 2012 dos detectores CMS e TOTEM, o qual permite ter uma perspectiva mais detalhada do processo difrativo, devido à aceitação completa que oferece a combinação dos detectores. Os dados foram corrigidos devido à aceitação e eficiência do detector. A partir de uma parametrização exponencial da forma Ae ^Bt, o valor da inclinação do processo em que o próton espalhado é detectado em ambas as direções positiva da CMS é de B= -6,403 1,241 GeV- . / The goal of the analysis presented in this dissertation is the measurement of the diffractive cross section d&#963;/d|t| at center of mass energy of &#8730;s = 8 TeV. The events were selected for single diffractive processes with one scattering proton in the forward region and the kinematic region of 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, using the data collected during 2012 by both the CMS and TOTEM detectors, whose joint acceptance allows a more detailed perspective of the diffractive processes. The data were corrected for the effects of detector acceptance and efficiency. Since the exponential parametrization Ae ^Bt was fit to data, the value obtained for the slope for a precess when the scattering proton is detected in both positive or negative regions of CMS is of B= -6,403 1,241 GeV- .

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Trajetória do grupo de literatura Totem, que se formou na cidade mineira de Cataguases e, no período dos anos de 1960 a 80, projetou sua obra no seu estado, atingiu muitas regiões do país e chegou ao exterior, por meio da edição de jornais, cartões-poemas, revistas e livros, bem como através de volumosa correspondência. Sua contribuição, principalmente na área da poesia experimental e da abertura para outros grupos, procurou sempre a pesquisa e a reformulação da linguagem poética. Buscou-se aqui o registro da experiência de uma equipe de jovens poetas, da qual participou o autor desta dissertação, e que, a partir de uma cidade do interior de Minas Gerais, conseguiu se situar bem no meio desse caldeirão de idéias que teve início na década de 60. / The trajectory of Totem literature group, formed in Cataguases, a small town located in Minas Gerais, Brazil. From the 1960s to the 1980s, Totem circulated its work in this State, reached a lot of parts of the country and abroad, through newspapers issues, poem-cards, magazines and books, as well as a great amount of correspondence. Its contribution, specially in the area of experimental poetry and the opening of other groups, Totem was always focused in poetry language reformulation and research. This paper aimed to record the experience of a group of young poets to which the author of this thesis belonged, describing how from that small town in Minas Gerais that group succeeded in including itself among the other groups and ideas of the early 1960s.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Trajetória do grupo de literatura Totem, que se formou na cidade mineira de Cataguases e, no período dos anos de 1960 a 80, projetou sua obra no seu estado, atingiu muitas regiões do país e chegou ao exterior, por meio da edição de jornais, cartões-poemas, revistas e livros, bem como através de volumosa correspondência. Sua contribuição, principalmente na área da poesia experimental e da abertura para outros grupos, procurou sempre a pesquisa e a reformulação da linguagem poética. Buscou-se aqui o registro da experiência de uma equipe de jovens poetas, da qual participou o autor desta dissertação, e que, a partir de uma cidade do interior de Minas Gerais, conseguiu se situar bem no meio desse caldeirão de idéias que teve início na década de 60. / The trajectory of Totem literature group, formed in Cataguases, a small town located in Minas Gerais, Brazil. From the 1960s to the 1980s, Totem circulated its work in this State, reached a lot of parts of the country and abroad, through newspapers issues, poem-cards, magazines and books, as well as a great amount of correspondence. Its contribution, specially in the area of experimental poetry and the opening of other groups, Totem was always focused in poetry language reformulation and research. This paper aimed to record the experience of a group of young poets to which the author of this thesis belonged, describing how from that small town in Minas Gerais that group succeeded in including itself among the other groups and ideas of the early 1960s.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A análise descrita nesta dissertação tem como objetivo a medida da seção de choque difrativa d&#963;/d|t| à energia no sistema do centro de massa de &#8730;s = 8 TeV. Os eventos usados para obter a seção de choque difrativa foram selecionados para processos de difração simples com um próton espalhado na região frontal e na região cinemática de 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, usando os dados em comum obtidos em 2012 dos detectores CMS e TOTEM, o qual permite ter uma perspectiva mais detalhada do processo difrativo, devido à aceitação completa que oferece a combinação dos detectores. Os dados foram corrigidos devido à aceitação e eficiência do detector. A partir de uma parametrização exponencial da forma Ae ^Bt, o valor da inclinação do processo em que o próton espalhado é detectado em ambas as direções positiva da CMS é de B= -6,403 1,241 GeV- . / The goal of the analysis presented in this dissertation is the measurement of the diffractive cross section d&#963;/d|t| at center of mass energy of &#8730;s = 8 TeV. The events were selected for single diffractive processes with one scattering proton in the forward region and the kinematic region of 0,03 <|t| < 1,0 GeV e 0,03 < &#958; < 0.1, using the data collected during 2012 by both the CMS and TOTEM detectors, whose joint acceptance allows a more detailed perspective of the diffractive processes. The data were corrected for the effects of detector acceptance and efficiency. Since the exponential parametrization Ae ^Bt was fit to data, the value obtained for the slope for a precess when the scattering proton is detected in both positive or negative regions of CMS is of B= -6,403 1,241 GeV- .

Hierdie verhandeling bied ʼn vergelykende ondersoek na ʼn aantal sogenaamde totemistiese aspekte in geselekteerde kunswerke van twee kunstenaars, Walter Battiss (1906-1982) en José Bedia (geb. 1959). Hierdie kunstenaars maak albei gebruik van ʼn benadering wat as primitivisties getipeer kan word. Die klem berus op hul soeke na unieke visuele tale deur die inkorporering van visuele en inhoudelike invloede uit primitiewe kunstradisies. Die ondersoek geskied aan die hand van ʼn metodologiese ontleding en interpretasie van Battiss se Symbols of life (1967) en José Bedia se Aquel lugar del fin del mundo (1999). Die ontledingsmetode is saamgestel vanuit ‘n besinning oor primitivisme en totemisme as teoretiese begronding en is op so ‘n wyse gerig om die hibridiese figure, oftewel teriantrope, in die onderskeie werke as totems te interpretasie met die doel om meer insig te bekom met betrekking tot die aard van hierdie figure asook die funksies waarvoor hierdie figure deur die kunstenaars gebruik is. Die gevolgtrekkings wat deur die ontleding en interpretasie van die geselekteerde kunswerke in hierdie studie gemaak word, behels dat die “lees” van die hibridiese figure in die onderskeie kunswerke as totems daarop dui dat alhoewel die aard en funksies van hierdie figure van mekaar verskil, daar wel noemenswaardige ooreenkomste is. Wat die aard van die hibridiese figure in Symbols of life (1967) betref, is hierdie figure geïdentifiseer as ‘n spesie van onbekende saamgestelde karakters waarvan die voorstellings gesamentlik ‘n bepaalde groep mense impliseer, naamlik die Boesmans, en dat die uitbeelding van hierdie figure mitiese en spirituele aspekte oproep van die Boesmans se wêreldbeskouings. Daarenteen is die hibridiese figuur in Bedia se Aquel lugar del fin del mundo (1999) geïdentifiseer as ‘n Cimarron wat as ‘n apikale totem op twee ontologiese vlakke figureer. Dit behels dat die uitbeelding van die Cimarron ‘n spesifieke wese voorstel wat beide ‘n groep mense oproep, naamlik lede van Sentraal-Amerikaanse Kreoolse kulture, en dat dit ook ‘n spesifieke individu oproep, naamlik Bedia self. Met betrekking tot die funksies wat die hibridiese figure in die geselekteerde kunswerke vervul, plaas Battiss doelbewus die aanskouer in kontak met ‘n onbekende mitiese andersheid wat as katalisator die aanskouer konfronteer met aspekte rakende die menslike kondisie. In teenstelling hiermee, betrek Bedia met die uitbeelding van die Cimarron ‘n spesifieke en hoogs gelade konteks wat bepaalde emosionele reaksies by die aanskouer kan ontlok. Die interpretasie van die hibridiese figure in die geselekteerde kunswerke as totems dui in beide gevalle daarop dat die kunstenaars deur hul onderskeie kunswerke van die die aanskouer vereis om epistemologiese en ontologiese besinnings te maak oor wat dit beteken om mens te wees, veral in ‘n eietydse omgewing, en noop verder van die aanskouer om te reflekteer oor waarheen die menslike kondisie ontwikkel met inagname ook van wat in die proses verlore mag gaan. Hierdie verhandeling behels ʼn interdissiplinêre studie waarin die klem op die kunsgeskiedenis berus, en waarin ter wille van die interpretasie van totems, ook gefokus word op die antropologiese studies rakende totemisme. / MA (History of Art), North-West University, Potchefstroom Campus, 2015

Hierdie verhandeling bied ʼn vergelykende ondersoek na ʼn aantal sogenaamde totemistiese aspekte in geselekteerde kunswerke van twee kunstenaars, Walter Battiss (1906-1982) en José Bedia (geb. 1959). Hierdie kunstenaars maak albei gebruik van ʼn benadering wat as primitivisties getipeer kan word. Die klem berus op hul soeke na unieke visuele tale deur die inkorporering van visuele en inhoudelike invloede uit primitiewe kunstradisies. Die ondersoek geskied aan die hand van ʼn metodologiese ontleding en interpretasie van Battiss se Symbols of life (1967) en José Bedia se Aquel lugar del fin del mundo (1999). Die ontledingsmetode is saamgestel vanuit ‘n besinning oor primitivisme en totemisme as teoretiese begronding en is op so ‘n wyse gerig om die hibridiese figure, oftewel teriantrope, in die onderskeie werke as totems te interpretasie met die doel om meer insig te bekom met betrekking tot die aard van hierdie figure asook die funksies waarvoor hierdie figure deur die kunstenaars gebruik is. Die gevolgtrekkings wat deur die ontleding en interpretasie van die geselekteerde kunswerke in hierdie studie gemaak word, behels dat die “lees” van die hibridiese figure in die onderskeie kunswerke as totems daarop dui dat alhoewel die aard en funksies van hierdie figure van mekaar verskil, daar wel noemenswaardige ooreenkomste is. Wat die aard van die hibridiese figure in Symbols of life (1967) betref, is hierdie figure geïdentifiseer as ‘n spesie van onbekende saamgestelde karakters waarvan die voorstellings gesamentlik ‘n bepaalde groep mense impliseer, naamlik die Boesmans, en dat die uitbeelding van hierdie figure mitiese en spirituele aspekte oproep van die Boesmans se wêreldbeskouings. Daarenteen is die hibridiese figuur in Bedia se Aquel lugar del fin del mundo (1999) geïdentifiseer as ‘n Cimarron wat as ‘n apikale totem op twee ontologiese vlakke figureer. Dit behels dat die uitbeelding van die Cimarron ‘n spesifieke wese voorstel wat beide ‘n groep mense oproep, naamlik lede van Sentraal-Amerikaanse Kreoolse kulture, en dat dit ook ‘n spesifieke individu oproep, naamlik Bedia self. Met betrekking tot die funksies wat die hibridiese figure in die geselekteerde kunswerke vervul, plaas Battiss doelbewus die aanskouer in kontak met ‘n onbekende mitiese andersheid wat as katalisator die aanskouer konfronteer met aspekte rakende die menslike kondisie. In teenstelling hiermee, betrek Bedia met die uitbeelding van die Cimarron ‘n spesifieke en hoogs gelade konteks wat bepaalde emosionele reaksies by die aanskouer kan ontlok. Die interpretasie van die hibridiese figure in die geselekteerde kunswerke as totems dui in beide gevalle daarop dat die kunstenaars deur hul onderskeie kunswerke van die die aanskouer vereis om epistemologiese en ontologiese besinnings te maak oor wat dit beteken om mens te wees, veral in ‘n eietydse omgewing, en noop verder van die aanskouer om te reflekteer oor waarheen die menslike kondisie ontwikkel met inagname ook van wat in die proses verlore mag gaan. Hierdie verhandeling behels ʼn interdissiplinêre studie waarin die klem op die kunsgeskiedenis berus, en waarin ter wille van die interpretasie van totems, ook gefokus word op die antropologiese studies rakende totemisme. / MA (History of Art), North-West University, Potchefstroom Campus, 2015

The education system in South Africa encourages the use of indigenous languages through policies that require full participation of teachers and elders. This case study explored the perceptions of teachers and elders of the use of folktale storysinging when teaching Setswana to young learners in the selected four provincial rural schools and villages. The aim was to investigate what folktale story songs they know and how they use them to communicate cultural customs and traditions embedded in them for young children’s future actualisation. The framework of the study was based on structuralism, functional-linguistic and ethnography of communication theories. A qualitative approach was undertaken in the form of group interviews, observations, field notes and documentation, including photo-voice. These instruments were analysed and grouped in themes and subthemes. The study assumed that teachers are professionals and are able to present Setswana folktale story lessons. The findings revealed that teachers, though being passionate and willing, were challenged by the folktale story books containing songs that they could not sing and contained grammatical errors as well as English words and sentences. They called on the parents (elders) with their totem understanding, for assistance, as the government seemed to be failing them through the implementation of language policies. However, it was found that elders sing folktale story songs to young children and even have the opportunity to give performances at the gatherings at the chief’s kraal but they did not regard themselves to be acknowledged by the teachers as responsible to give assistance to them. In the complex linguistic context in South Africa, speakers of a minority language need to understand that language and culture can be retained and transmitted but this understanding needs commitment from the speakers; in this case Setswana. / Tsamaiso ya thuto mo Aferika Borwa e rotloetsa tiriso ya dipuo tsa bantsho tsa setso ka go latela melaotheo e e gwetlhang barutabana le bagolo go tsaya karolo. Dipatlisiso tse di begwang mo, di tsenelela sebopego se barutabana le bagolo ba dirisang molodi-dinaaneng go ruta bana ba bannye Setswana mo dikolong tse dipotlana le metse-magaeng e e mabapi go tswa mo dikgaolopusong tse nne. Maikaelelomagolo ke go lekola gore ke melodi efe ya dinaane e ba e itseng le gore ba e dirisa jang go goroseng molaetsa wa ngwao ya setso o o leng mo dinaaneng, go ruta bana ba bannye gore ba tshele ka tsona fa ba gola. Tshekatsheko e, e theilwe godimo ga diteori tsa molebokagego, molebobodirisego le molebo wa setso wa tlhaeletsano. Leano la go kokoanya kitso ya go dira dipatlisiso le go fitlhela batsayakarolo go ntsha maikutlo a bona, e nnile ka mokgwa wa dipuisano ka setlhopha, go lebelela, go kwala le go buisa dikwalwa. Didiriswa tse tsa dipatlisiso, di dirisitswe go sekaseka kitso e e tswang go batsayakarolo, moo go neng ga runya dikarolo le dikarolwana tsa melaetsa maleba le kgang e ya go batlisisa ka ga molodi-naaneng. Tshekasheko e e dirilwe ka kgopolo ya gore barutabana ke bomaitseanape mo tirong ya bona, ba kgona le go ruta molodi wa dinaane tsa Setswana. Tshenolo ya dipatlisiso e supile gore le fa barutabana ba rata e bile ba na le tlhoafalo mo tirong ya bona, ba ne ba sitiswa ke dibuka tse ba di dirisang go ruta dinaane ka di ne di na le dipina tse ba sa kgoneng go di opela, gape di ne di na le diphoso tsa mokwalo le tiriso ya mafoko a sekgowa. Ka la ntlheng, go tsweletse gore bagolo bona ba opelela bana dipina tsa dinaane e bile ba kgona go bona tšhono ya go di tsweletsa mo dikopanong kwa kgosing. Le gale, ba ne ba bona gore barutabana ga ba lemoge mosola wa bona wa go ka tsaya karolo mo go ruteng bana dipina tsa dinaane. Fela jaaka go na le dipuo tse di farologaneng mo Aferika Borwa, bengdipuo-potlana ba tshwanetse go tlhaloganya loleme lwaabo gore ba kgone go somarela setso sa bona le go fetisetsa loleme loo tshikatshikeng. Foo go batlega itapiso go tswa go bengpuo ya Setswana mo kgannyeng e. / Thesis (PhD)--University of Pretoria, 2016. / EU DHET / Early Childhood Education / PhD / Unrestricted

Le grand collisionneur d'hadrons (LHC) a commencé les opérations de faisceau de protons le 10 septembre 2008. Respectant le programme prévu pour les prochaines années, le LHC devrait démontrer ou réfuter l'existence du boson de Higgs de façon réaliste d'ici 2014. Après cette date il est raisonnable de prévoir l'amélioration de la luminosité de la machine pour explorer en détail la physique des événements rares.<br />Le présent travail de thèse propose différentes idées pour augmenter la luminosité des expériences ATLAS et CMS, les deux principales expériences du programme scientifique du LHC. Une idée pour l'amélioration de l'acceptance de l'expérience TOTEM est aussi présentée. <br />L'ensemble des aimants qui réalisent la focalisation finale du faisceau avant la collision ont été pris en considération pour augmenter la luminosité dans les zones expérimentales. Les nouvelles configurations ont été étudiées en utilisant des méthodes d'optique des accélérateurs et de dynamique des faisceaux. L'intégration des solutions a été aussi explorée en analysant les énergies déposées dans les différents éléments et les tolérances des alignements. <br />Un nouveau schéma optique pour augmenter l'acceptance de l'expérience TOTEM utilisant les cristaux de silicium est aussi présenté. Les résultats attendus sont comparés avec les résultats actuels.<br />Les études ont été menées en utilisant des méthodes analytiques pour les considérations générales et des méthodes numériques pour l'optimisation des paramètres.<br />Les résultats présentés dans cette thèse ont été publiés et présentés dans différentes conférences et workshops internationaux.

The proton, one of the basic constituents of atoms, was discovered around 1920. Its structure has been intensively studied since that time mainly with the help of proton- proton collision experiments. Main progress has started when corresponding experiments at the world's first hadron collider ISR at CERN which ran from 1971 to 1984 were performed. The understanding of the structure and interactions of this subatomic particle protons has been, however, rather incomplete. Only some very general models have been available especially in the case of higher collision energies when very different kinds of collisions have existed. Some very simplifying assumptions of unclear physical meaning have been then involved in models concerning elastic processes. The influence of these assumptions on physical interpretation has started to be studied and some progress has been made when the eikonal model has been proposed, i.e., the dependence of elastic collisions on corresponding impact parameter values has been taken into account from the beginning. However, even if some new results have been obtained many unanswered questions have remained. For example, the collision process has been denoted generally as probabilistic but corresponding probabilities have not been sufficiently defined and determined. The given thesis contains,...