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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.
181

Doping im Hochleistungssport : eine ökonomische Analyse /

Pirnat, Jochen. January 2008 (has links)
Zugl.: Innsbruck, Universiẗat, Dipl.-Arb., 2005.
182

No limiar do humano : doping e performance esportiva em perspectiva antropológica

Silbermann, Marcos January 2014 (has links)
Esta dissertação tem como objeto as controvérsias instauradas a partir doping e o combate contra a sua utilização. Com o limite continuamente demarcado entre doping e antidoping, entre o lícito e o ilícito do esporte, os próprios limites do corpo, da natureza e do humano são traçados. Nesta direção desenvolver uma abordagem que descreva os coletivos sociotécnicos articulados a partir e através deste permanente conflito entre doping e antidoping é a via de entrada para uma melhor compreensão das relações entre esporte e tecnologia na atualidade. Seja, na performance atlética, que passa a ser compreendida como uma realidade intrinsecamente heterogênea a partir dos diversos artefatos sociotécnicos, conceituais e materiais envolvidos em sua constituição. Como nos contra investimentos realizados pelas instituições esportivas com o intuito de coibir e detectar as práticas de doping. No intuito de apreender como estas relações complexas produzem diversos dispositivos técnicos e conceituais que atuam nas intersecções entre o esporte profissional e a tecnociência, constituindo novas práticas e saberes sobre o corpo do atleta. Por fim, tensionando o anthropos como figura conceitual, tanto eticamente, questionando o que sabemos e compreendemos como humano, como disciplinarmente, explicitando os limites metodológicos da análise antropológica, quando se estabelece como um empreendimento disciplinar, que visa à compreensão do humano. / This dissertation has as its object the controversies brought from doping and combating its use. With the continuously demarcated boundary between doping and anti-doping, between licit and illicit in sport, the limits of the body nature and the human are traced. In this direction the dissertation develops an approach that describes the pleadings from sociotechnical collectives and through this ongoing conflict between doping and antidoping is the entry pathway to a better understanding of the relationship between sport and technology nowadays. An athletic performance shall be understood as a reality intrinsically heterogeneous composed through the socio-technical relations, conceptual and material involved in its constitution , as in the investments made by the sports institutions in order to curb and detect doping practices. In order to grasp how these complex relationships produce various technical and conceptual devices that operate at the intersections between professional sport and technoscience, building new practices and knowledge about the athlete's body. Finally, tensing the anthropos as a conceptual figure, both ethically questioning what we know and understand as human as disciplinary, highlighting the methodological limits of anthropological analysis, when it happens as disciplinary project, which aims at understanding the Human.
183

Antidopingová praxe v řízení ruského sportu / Russian Sport Management Anti-doping Practice

Ornstová, Kateřina January 2018 (has links)
Title: Russian Sport Management Anti-doping Practice Objectives: I would like to point up how is practical antidoping working in Russia in sport. Sanction which were imposition to Russia in sports world and approach Russia sports mentality. I the end found out public opinions about this problem. Methods: Document analysis, internet questionair, interview. Results: I am combinating results from my work with explanation how is antidoping politics working in Russia and on the world. The results containing Russia sanctions and opinions of respondents to doping problemations. Keywords: Sport, Doping, Anti-doping Convention, Sports legislation, IOC.
184

No limiar do humano : doping e performance esportiva em perspectiva antropológica

Silbermann, Marcos January 2014 (has links)
Esta dissertação tem como objeto as controvérsias instauradas a partir doping e o combate contra a sua utilização. Com o limite continuamente demarcado entre doping e antidoping, entre o lícito e o ilícito do esporte, os próprios limites do corpo, da natureza e do humano são traçados. Nesta direção desenvolver uma abordagem que descreva os coletivos sociotécnicos articulados a partir e através deste permanente conflito entre doping e antidoping é a via de entrada para uma melhor compreensão das relações entre esporte e tecnologia na atualidade. Seja, na performance atlética, que passa a ser compreendida como uma realidade intrinsecamente heterogênea a partir dos diversos artefatos sociotécnicos, conceituais e materiais envolvidos em sua constituição. Como nos contra investimentos realizados pelas instituições esportivas com o intuito de coibir e detectar as práticas de doping. No intuito de apreender como estas relações complexas produzem diversos dispositivos técnicos e conceituais que atuam nas intersecções entre o esporte profissional e a tecnociência, constituindo novas práticas e saberes sobre o corpo do atleta. Por fim, tensionando o anthropos como figura conceitual, tanto eticamente, questionando o que sabemos e compreendemos como humano, como disciplinarmente, explicitando os limites metodológicos da análise antropológica, quando se estabelece como um empreendimento disciplinar, que visa à compreensão do humano. / This dissertation has as its object the controversies brought from doping and combating its use. With the continuously demarcated boundary between doping and anti-doping, between licit and illicit in sport, the limits of the body nature and the human are traced. In this direction the dissertation develops an approach that describes the pleadings from sociotechnical collectives and through this ongoing conflict between doping and antidoping is the entry pathway to a better understanding of the relationship between sport and technology nowadays. An athletic performance shall be understood as a reality intrinsically heterogeneous composed through the socio-technical relations, conceptual and material involved in its constitution , as in the investments made by the sports institutions in order to curb and detect doping practices. In order to grasp how these complex relationships produce various technical and conceptual devices that operate at the intersections between professional sport and technoscience, building new practices and knowledge about the athlete's body. Finally, tensing the anthropos as a conceptual figure, both ethically questioning what we know and understand as human as disciplinary, highlighting the methodological limits of anthropological analysis, when it happens as disciplinary project, which aims at understanding the Human.
185

No limiar do humano : doping e performance esportiva em perspectiva antropológica

Silbermann, Marcos January 2014 (has links)
Esta dissertação tem como objeto as controvérsias instauradas a partir doping e o combate contra a sua utilização. Com o limite continuamente demarcado entre doping e antidoping, entre o lícito e o ilícito do esporte, os próprios limites do corpo, da natureza e do humano são traçados. Nesta direção desenvolver uma abordagem que descreva os coletivos sociotécnicos articulados a partir e através deste permanente conflito entre doping e antidoping é a via de entrada para uma melhor compreensão das relações entre esporte e tecnologia na atualidade. Seja, na performance atlética, que passa a ser compreendida como uma realidade intrinsecamente heterogênea a partir dos diversos artefatos sociotécnicos, conceituais e materiais envolvidos em sua constituição. Como nos contra investimentos realizados pelas instituições esportivas com o intuito de coibir e detectar as práticas de doping. No intuito de apreender como estas relações complexas produzem diversos dispositivos técnicos e conceituais que atuam nas intersecções entre o esporte profissional e a tecnociência, constituindo novas práticas e saberes sobre o corpo do atleta. Por fim, tensionando o anthropos como figura conceitual, tanto eticamente, questionando o que sabemos e compreendemos como humano, como disciplinarmente, explicitando os limites metodológicos da análise antropológica, quando se estabelece como um empreendimento disciplinar, que visa à compreensão do humano. / This dissertation has as its object the controversies brought from doping and combating its use. With the continuously demarcated boundary between doping and anti-doping, between licit and illicit in sport, the limits of the body nature and the human are traced. In this direction the dissertation develops an approach that describes the pleadings from sociotechnical collectives and through this ongoing conflict between doping and antidoping is the entry pathway to a better understanding of the relationship between sport and technology nowadays. An athletic performance shall be understood as a reality intrinsically heterogeneous composed through the socio-technical relations, conceptual and material involved in its constitution , as in the investments made by the sports institutions in order to curb and detect doping practices. In order to grasp how these complex relationships produce various technical and conceptual devices that operate at the intersections between professional sport and technoscience, building new practices and knowledge about the athlete's body. Finally, tensing the anthropos as a conceptual figure, both ethically questioning what we know and understand as human as disciplinary, highlighting the methodological limits of anthropological analysis, when it happens as disciplinary project, which aims at understanding the Human.
186

Teoria do Confinamento de Buracos em Heteroestruturas Semicondutoras do Tipo Delta-doping / Hole confinement theory of delta-doping semiconductor heterostructures

Guilherme Matos Sipahi 10 September 1997 (has links)
Poços e super-redes delta-doping tipo são sistemas semicondutores de interesse considerável tanto para a pesquisa básica como para aplicações em dispositivos. Neste trabalho desenvolvemos um novo método para o cálculo de potenciais e estruturas de bandas deste tipo de sistemas. O método baseia-se na expansão em ondas planas da equação da massa efetiva multibandas, usa matrizes de energia cinética de qualquer tamanho e leva em conta o potencial de troca e correlação de uma maneira mais rigorosa do que em trabalhos anteriores. São calculados perfis de potencial e estrutura de minibandas e subbandas bem como a posição do nível de Fermi de uma série de poços isolados e super-redes delta-doping tipo p. São estudadas também as diferenças entre super-redes delta-doping tipo p e tipo n. A partir deste método foi desenvolvido ainda um procedimento de cálculo de espectros de fotoluminescência dos poços estudados. Este procedimento baseia-se nas forças de oscilador das transições entre os buracos confinados no interior do poço e os elétrons livres da banda de condução. Ele é utilizado para calcular funções envelope, integrais de superposição e espectros de transições diretas e indiretas. Por fim, comparamos espectros calculados teoricamente com resultados experimentais extraídos da literatura. / p-type ro-doping quantum wells and superlattices are semiconductor systems of considerable interest for basic research and device applications. In this work, a method for calculating potentials and band structures of such systems is developed. The method relies on a plane wave expansion of the multiband effective mass equation, uses kinetic energy matrices of any size, and takes exchange correlation into account in a more rigorous way than this was done before. The method is used to calculate potential profiles, subband and miniband structures as well as Fermi level positions for a series of p-type delta-doping quantum wells and superlattices. The differences between n- and p-type delta-doping structures are studied. In addition to this we developed a procedure within this method to ca1culate photoluminescence (PL) spectra of the wells studied. It depends on the oscillator strength between the holes inside the wells and the free electrons on the conduction band. We use this procedure to calculate envelope functions, overlap integrals and direct and indirect transitions spectra. Finally, we compare our theoretical calculations of PL spectra with experimental results extracted from the literature.
187

[en] CARBON DOPING IN INAIAS EPITAXIAL LAYERS / [pt] DOPAGEM CARBONO EM CAMADAS EPITAXIAIS DE INALAS

MARIO LUIS PIRES GONCALVES RIBEIRO 24 May 2002 (has links)
[pt] É reconhecido o potencial de usar carbono como um dopante tipo p em InAlAs devido a obtenção de elevados níveis de dopagem [1,2]. Entretanto, níveis elevados de dopagem só são alcançados em baixas temperaturas de crescimento (Tg inferiores a 600°C). Nessas temperaturas, as camadas crescidas apresentam qualidade ótica inferior quando comparadas com camadas crescidas em temperaturas mais altas, o que é prejudicial para dispositivos de optoeletrônica. Neste trabalho, é apresentada uma investigação sistemática das propriedades de transporte e óticas em camadas de InAlAs dopadas com carbono para diferentes temperaturas de crescimento. É observado que quanto mais baixa for a Tg maior será a incorporação de carbono e maior a atividade elétrica. Este resultado indica que o carbono é incorporado de diversas maneiras, bem como um aceitador raso. O carbono também pode ser incorporado como um doador raso, pois é um dopante anfotérico. Entretanto, este fato, não é suficiente para explicar os resultados de transporte. A diferença entre a concentração Hall e a concentração CV indica a incorporação de doadores profundos. Provavelmente, o carbono participa na formação desses doadores profundos, uma vez que a concentração de doador profundo varia linearmente com a densidade atômica de carbono, determinada pela técnica SIMS. Por outro lado, centros não radiativos são mais facilmente incorporados em baixas Tg e a eficiência da fotoluminescência é reduzida. Essa degradação da fotoluminescência é independente da concentração de carbono, consequentemente, pode-se concluir que essa redução na eficiência da fotoluminescência não está associada à presença de doadores profundos. Com a finalidade de obter um incremento na atividade elétrica do carbono e melhoria na qualidade ótica das camadas, as amostras foram submetidas a tratamentos térmicos. Os tratamentos térmicos aumentaram a concentração de buracos mas não influenciaram na densidade de doadores profundos ou na qualidade ótica das camadas. Para a utilização de InAlAs dopado com carbono em dispositivos, deve-se obter simultaneamente uma boa qualidade ótica e elevada atividade elétrica das camadas.Então, deve-se identificar o doador profundo, que está associado ao carbono, com o objetivo de reduzí-lo ou eliminá-lo e consequentemente, obter um incremento na atividade elétrica das camadas. Desta forma as camadas podem ser crescidas a temperaturas mais altas adequadas para uma emissão de fotoluminescência eficiente. Cálculos teóricos são apresentados de modo a ajudar essa identificação. Outra possibilidade é usar diferentes fontes de arsina em que as moléculas se dissociem em temperaturas mais baixas. / [en] The potential of using carbon as a p-type dopant for InAlAs has already been recognized due to the achievable high hole concentration [1,2]. However, high doping levels are reached only for low growth teperatures (Tg below 600°C). These temperatures produce layers with poor optical quality as compared to those grown at higher temperatures, which can be detrimental for optoeletronic device. In this work we present crystal, transport and optical properties of such layers grown at different temperatures. We find that the lower Tg, the more efficient the carbon incorporation and its electrical activity are. This result indicates that carbon is incorporated in forms different from a shallow acceptor, as well. Carbon can also be incorporated as a shallow donor since it is an amphoteric dopant. However, this alone does not explain the transport results. The difference between the net free charge density determined from capacitance measurements indicates that a deep donor is also incorporated. Carbon most likely participates in the deep donor formation since the inferred deep donor concentration varies linearly with the carbon atomic density measured by SIMS. On the other hand, non- radiative deep levels are more efficiently incorporated as Tg is reduced degrading the photoluminescence characteristics. Such degration is independent of the carbon doping. Therefore, one concludes that the decrease in the photoluminescence efficiency cannot be related to the presence of the deep donor mentioned in the previous paragraph. To further probe the carbon electrical activity and its effect on the optical properties of the layers, the samples have been subjected to a heat-treatment. Annealing the samples increases the hole concentration, but neither affects the deep donor density nor improves the layers optical quality. In order to use carbon doped InAlAs in devices which simultaneously require good optical quality and high electrical activity of the layers, one should identify the deep donor involving carbon in order to try to reduce its concentration or even eliminate it, consequently improving the electrical activity of the layers. In such a way the layers can be grown at higher temperatures, adequate for an efficient photoluminescence emission. Theoretical calculations are being carried out to help with such identification. Another possibility is to use other arsine sources which crack at lower temperatures.
188

Characterization of the equine metabolites of LGD-4033 in urine using UHPLC-MS(/MS) for doping control purposes

Liora, Jackson January 2017 (has links)
The aim of this project was to study and characterize the metabolitesof LGD-4033 in equine urine, with the final aim of using the results indoping controls in equestrian sports. Urine samples had been taken atdifferent points in time from three horses that had received thesubstance intravenously. The samples were both directly analysed usinga so called dilute-and-shoot approach and were also prepared with amixed mode anion exchange solid phase extraction. All analysis weredone with UHPLC-ESI-MS(/MS) in negative mode. A total of eightmetabolites were found, which were all combinations of phase Ihydroxylation and/or phase II glucuronidation. Of these a total of four(one that is both monohydroxylated and glucuronidated, one that isdihydroxylated, as well as two glucuronidated metabolites) would besuitable for doping control.
189

Heteroatom-Doped Chemical Vapor Deposition Carbon Ultramicroelectrodes

Sanwick, Alexis 01 May 2020 (has links)
Metal nanoparticles have been a primary focus in areas of catalysis and electrocatalysis applications as a result of their large surface area-to-volume ratios. While there is an increased interest in understanding the properties and behaviors of metal nanoparticles, they can become expensive over time. Recent research has incorporated the idea of using heteroatom-doped materials as a cheaper catalytic alternative to metal nanoparticles. In this study nitrogen-doping and phosphorous-doping techniques were applied to chemical vapor-deposited carbon ultramicroelectrodes in order to study the electrocatalytic properties toward the oxygen reduction reaction and the enhanced affinity for the deposition of gold nanoparticles onto the electrodes.
190

Influence of Carrier Freeze-Out on SiC Schottky Junction Admittance

Los, Andrei 12 May 2001 (has links)
Silicon carbide is a very promising semiconductor material for high-power, highrequency, and high-temperature applications. SiC distinguishes from traditional narrow bandgap semiconductors, such as silicon, in that common doping impurities in SiC have activation energies larger than the thermal energy kT even at room temperature. This causes incomplete ionization of such impurities, which leads to strong temperature and frequency dependence of the semiconductor junction differential admittance and, if carrier freeze-out effects are not taken into account, errors in doping profiles calculated from capacitance-voltage data. Approaches commonly used to study the influence of incomplete impurity ionization on the junction admittance are based on the truncated space charge approximation and/or the small-signal approximation. The former leads to impurity ionization time constant and occupation number errors, while the latter fails if the measurement ac signal amplitude is larger than kT/q. In this work, a new reverse bias Schottky junction admittance model valid for the general case of an arbitrary temperature, measurement signal frequency and amplitude, and doping occupation number and time constant distributions is developed. Results of junction admittance calculations using the developed model are compared with the results of traditional models. Based on the general model, a new method of admittance spectroscopy data analysis is created and used to determine impurity parameters more accurately than allowed by traditional approaches. Incomplete impurity ionization is investigated for the case of nitrogen donors and aluminum and boron acceptors in 4H- and 6H-SiC. It is shown that the degree of carrier freeze-out is significant in heavily N-doped 6H-SiC and in Al- and B-doped SiC. Frequency dispersion of the junction admittance is shown to be significant at room temperature in N- and B-doped SiC. Junction capacitance calculations as a function of applied dc bias show that calculated doping profiles deviate from the actual impurity concentration profiles if the impurity ionization time constant is comparable with the ac signal period. This is the case for N- and B-doped SiC with certain values of the impurity activation energy and capture cross-section. Validity of the new model and its predictions are successfully tested on experimental admittance data for N- and B-doped SiC Schottky diodes.

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