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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.
91

Bridges of Markov counting processes : reciprocal classes and duality formulas

Conforti, Giovanni, Léonard, Christian, Murr, Rüdiger, Roelly, Sylvie January 2014 (has links)
Processes having the same bridges are said to belong to the same reciprocal class. In this article we analyze reciprocal classes of Markov counting processes by identifying their reciprocal invariants and we characterize them as the set of counting processes satisfying some duality formula.
92

Quantitative NDA Measurements of Advanced Reprocessing Product Materials Containing U, NP, PU, and AM

Goddard, Braden 03 October 2013 (has links)
The ability of inspection agencies and facility operators to measure powders containing several actinides is increasingly necessary as new reprocessing techniques and fuel forms are being developed. These powders are difficult to measure with nondestructive assay (NDA) techniques because neutrons emitted from induced and spontaneous fission of different nuclides are very similar. A neutron multiplicity technique based on first principle methods was developed to measure these powders by exploiting isotope-specific nuclear properties, such as the energy-dependent fission cross sections and the neutron induced fission neutron multiplicity. This technique was tested through extensive simulations using the Monte Carlo N-Particle eXtended (MCNPX) code and by one measurement campaign using the Active Well Coincidence Counter (AWCC) and two measurement campaigns using the Epithermal Neutron Multiplicity Counter (ENMC) with various (α,n) sources and actinide materials. Four potential applications of this first principle technique have been identified: (1) quantitative measurement of uranium, neptunium, plutonium, and americium materials; (2) quantitative measurement of mixed oxide (MOX) materials; (3) quantitative measurement of uranium materials; and (4) weapons verification in arms control agreements. This technique still has several challenges which need to be overcome, the largest of these being the challenge of having high-precision active and passive measurements to produce results with acceptably small uncertainties.
93

Implementing the Schoof-Elkies-Atkin Algorithm with NTL

Kok, Yik Siong 25 April 2013 (has links)
In elliptic curve cryptography, cryptosystems are based on an additive subgroup of an elliptic curve defined over a finite field, and the hardness of the Elliptic Curve Discrete Logarithm Problem is dependent on the order of this subgroup. In particular, we often want to find a subgroup with large prime order. Hence when finding a suitable curve for cryptography, counting the number of points on the curve is an essential step in determining its security. In 1985, René Schoof proposed the first deterministic polynomial-time algorithm for point counting on elliptic curves over finite fields. The algorithm was improved by Noam Elkies and Oliver Atkin, resulting in an algorithm which is sufficiently fast for practical purposes. The enhancements leveraged the arithmetic properties of the l-th classical modular polynomial, where l- is either an Elkies or Atkin prime. As the Match-Sort algorithm relating to Atkin primes runs in exponential time, it is eschewed in common practice. In this thesis, I will discuss my implementation of the Schoof-Elkies-Atkin algorithm in C++, which makes use of the NTL package. The implementation also supports the computation of classical modular polynomials via isogeny volcanoes, based on the methods proposed recently by Bröker, Lauter and Sutherland. Existing complexity analysis of the Schoof-Elkies-Atkin algorithm focuses on its asymptotic performance. As such, there is no estimate of the actual impact of the Match-Sort algorithm on the running time of the Schoof-Elkies-Atkin algorithm for elliptic curves defined over prime fields of cryptographic sizes. I will provide rudimentary estimates for the largest Elkies or Atkin prime used, and discuss the variants of the Schoof-Elkies-Atkin algorithm using their run-time performances. The running times of the SEA variants supports the use Atkin primes for prime fields of sizes up to 256 bits. At this size, the selective use of Atkin primes runs in half the time of the Elkies-only variant on average. This suggests that Atkin primes should be used in point counting on elliptic curves of cryptographic sizes.
94

Deep freezing of concentrated boar semen for intra-uterine insemination /

Saravia, Fernando, January 2004 (has links) (PDF)
Thesis (M. Sc.) Uppsala : Sveriges lantbruksuniv.
95

Medida absoluta da taxa de desintegracao e da probabilidade de emissao gama do sup[42]K

MOREIRA, DENISE S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:44:15Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:24Z (GMT). No. of bitstreams: 1 06884.pdf: 3958157 bytes, checksum: d230858464baf1ab2ee2867cf97407e4 (MD5) / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
96

Descricao, caracteristicas e desempenho de um prototipo de contador de corpo inteiro para uso clinico

KIEFFER, JULIO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:23:41Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:57:36Z (GMT). No. of bitstreams: 1 00617.pdf: 4446323 bytes, checksum: 2472e6b6e02afc6e4ba94b64e17ccf87 (MD5) / Tese (Doutoramento) / IEA/T / Faculdade de Medicina, Universidade de Sao Paulo - FM/USP
97

Mundane self-tracking : calorie counting practices with MyFitnessPal

Didziokaite, Gabija January 2017 (has links)
This thesis investigates self-tracking practices of users of MyFitnessPal calorie counting app. The thesis researches everyday self-trackers users who have started using the app on their own and are not part of any self-tracking community and focuses on the practices of self-tracking. The thesis responds to the literature on self-tracking that has often neglected everyday self-trackers and practices of self-tracking. First, many studies, whether sociological investigations or human-computer interaction research, focus on members of Quantified Self (QS) community (Choe, Lee, Lee, Pratt, & Kientz, 2014; Li, Dey, & Forlizzi, 2010; Neff & Nafus, 2015; Sharon & Zandbergen, 2016). QS is a community of individuals who are interested in learning more about themselves through, oftentimes unusual and complex, self-tracking, which involves modification of existing technologies or even creation of new ones. Thus, focusing on QS members neglects the individual everyday self-trackers, their experiences and practices. Second, existing studies have mainly focused on health or social implications of self-tracking (Lupton, 2012b, 2013d, 2014a, Swan, 2012b, 2013). These include, but are not limited to, potential of self-tracking to assist diagnosis (Wile, Ranawaya, & Kiss, 2014), or behaviour change (Chiauzzi, Rodarte, & Dasmahapatra, 2015), self-tracking increasing surveillance, public pedagogy (Rich & Miah, 2014) and subjection to neoliberal values and promotion of healthism (Lupton, 2012b, 2013a) or leading to monetisation of exercise (Till, 2014). While these studies have yielded important insights, they do not help us to understand what people actually do when they self-track, i.e. what practices self-tracking involves and how people engaged in self-tracking manage them. Guided by the STS approach that highlights the importance of observing the mundane practices and need to focus on technology users, this thesis explores the practices of everyday self-trackers. The exploration of the practices of self-tracking among the everyday self-trackers is based on 31 interviews with early mid-life individuals, who were mainly recruited from gyms and shared their self-tracking experience of using the MyFitnessPal calorie counting app. The analytical chapters answer three questions: What is self-tracking by calorie counting in the everyday like? How is self-tracking by calorie counting done? What are the practices through which self-tracking affects those engaged in it? To answer the first question, I juxtapose self-tracking goals, use and effects as they are represented in the literature on the QS to those of my participants. Doing this reveals that self-tracking in the everyday is perceived and done quite differently than the QS metaphor would allow us to believe. The goals of the participants are mundane (weight loss), they do not use the sophisticated features of the app and are not interested in the historical data, the effects of the app are not life-changing and temporary closely tied to the use of the app. This stands in contrast to QS metaphor where self-tracking is geared towards continuous self-improvement, driven by intricate data analysis and biohacking. To answer the second question, I focus on self-tracking by calorie counting with MyFitnessPal as a dieting practice. I explore how self-tracking affects the daily practices as well as is incorporated in participants lives. The users, thus, aim to find an approach to temporal aspects of tracking and precision that would fit most conveniently with their other daily practices. They manipulate their use of the app to accommodate any meals that are not in their usual dieting routine. This highlights that dieting through self-tracking is not a straightforward data collection and involves practical strategies and negotiations, and can both influence and be influenced by other everyday practices. The third question focuses on quantification, that is the production and communication of numbers (W. N. Espeland & Stevens, 2008, p. 402). Quantification has usually been discussed at institutional levels, in terms of government, science or, in the case of Espeland and Sauder s (W. N. Espeland & Sauder, 2007) seminal work, in terms of academic rankings. I adopt the insights from these studies to make sense of the quantification at the individual level using MyFitnessPal. I draw out two features of individual quantification that distinguish it from institutional one, mainly that quantification is done for oneself only and it relies on self-governance. Further, I outline how quantification affects such decisions as whether to eat, what to eat and how much to eat. Quantification also works as commensuration as participants compared different foods referring to their calorie value. However, unlike in the case of institutional quantification, individual quantification did not have to be accepted unquestionably and often other values of food would be weighted in relation to calories when participants made choices what to eat. Ultimately, this thesis contributes a new perspective on self-tracking as it explores the mundanity of it. It adds fine-grained insights into the everyday practices of self-tracking by adopting a novel analytical angle that centres on practices and by exploring a neglected user group of everyday self-trackers.
98

Composição aditiva e contagem em crianças surdas : intervenção pedagógica com filhos de surdos e de ouvintes

Vargas, Rosane da Conceição January 2011 (has links)
A presente pesquisa investigou a composição aditiva e a contagem com crianças surdas. O estudo se justifica pelo baixo desempenho em matemática que as crianças surdas têm apresentado a partir de testes padronizados de avaliação matemática, indicando que possivelmente as crianças surdas, estão em desvantagens em matemática inicial em relação a seus pares ouvintes. O estudo tem como objetivos: analisar o desenvolvimento da composição aditiva em crianças surdas no contexto brasileiro; identificar se há relação entre contagem, princípios da contagem e desenvolvimento da composição aditiva em crianças surdas; verificar variações do desenvolvimento da composição aditiva em criança surda, filha de surdos, e surda, filha de ouvintes; testar a eficácia de uma proposta de intervenção que trabalha com a composição aditiva e procedimentos de contagem. Consistiu em dois Estudos de Caso exploratório, de análise qualitativa. Fundamenta-se na concepção epistemológica cognitivista de Vergnaud, e volta-se para as aprendizagens da composição aditiva e evolução dos procedimentos e estratégias de contagem. Envolveu duas crianças surdas, sendo uma filha de pais surdos e outra filha de pais ouvintes, selecionadas por teste de habilidade cognitiva, idade, ano escolar, perda auditiva, domínio da LIBRAS. Os alunos selecionados participaram de oito encontros de intervenção individual, ao longo do segundo semestre de 2010, sendo submetidos a pré-teste e dois pós-teste. A pesquisa evidenciou um processo de construção da composição aditiva e evolução dos procedimentos de contagem de forma não linear. Também evidenciou uma relação de desenvolvimento paralela entre composição aditiva e avanços na habilidade de procedimentos de contagem. Não houve diferença significativa das aprendizagens entre a criança filha de surdos e a criança surda filha de ouvintes. A proposta de intervenção, através da comparação do préteste e pós-teste se mostrou eficaz. / This study examined the development of additive composition and counting by a school-aged deaf child of hearing parents. The study is justified by the low Math performance by deaf children in math standardized tests, indicating a possible disadvantage regarding their hearing peers. The aims of the research were: examining the development of additive composition by deaf children in the context of Brazil; verifying whether or not there is any relationship between counting, counting principles, and development of additive composition by deaf children; checking for variations in the development of additive composition by a deaf child of deaf parents and a deaf child of hearing parents; testing for the effectiveness of an intervention that works with additive composition and counting procedures. This was an exploratory qualitative study that consisted in a dual case study. It is based on Vergnaud’s (1990) cognitivist epistemological conception and focuses on learning of additive composition and the evolution of counting procedures and strategies. It involved two deaf children of respectively deaf and hearing parents, selected according to cognitive ability testing, age, school level, hearing loss, and command of Brazilian Sign Language LIBRAS. The students selected attended eight meetings for individual intervention during the second half of 2010, and underwent one pretest and two posttests. As a result, the study showed a process of construction of additive composition and nonlinear development of counting procedures. It also showed a parallel relationship in developing additive composition and progress in counting procedures ability. There was no significant difference between learning in a deaf child of deaf parents and in a deaf child of hearing parents. Therefore, by comparing pretest and posttest, the proposal for intervention proved to be effective.
99

Influência de variáveis climáticas e possibilidade de fraude em parâmetros da IN 62 utilizados pelos programas de pagamento por qualidade de leite

Oliveira, Mônica Costa [UNESP] 24 June 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:51Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-06-24Bitstream added on 2014-06-13T20:04:27Z : No. of bitstreams: 1 oliveira_mc_dr_jabo.pdf: 557837 bytes, checksum: d166a1b1c735091a58dd19500f6fa6d4 (MD5) / Com o Brasil aumentando cada vez mais a produção de leite houve uma preocupação maior com a qualidade do leite e seus derivados. Em 2011 foi implantada a Instrução Normativa 62 (IN 62) em 29 de dezembro de 2011 que revogou a Instrução Normativa 51 (IN 51) de 18 de setembro de 2002. Dentre as alterações, as principais foram sobre os limites de contagem de células somáticas (CCS) e contagem bacteriana total (CBT). Para que os produtores fornecessem um produto com qualidade, as empresas paralelamente ao governo federal implantaram programas de qualidade do leite, que bonificam ou penalizam os produtores pela qualidade do leite produzido. Com isso a presente pesquisa teve como objetivo avaliar amostras de leite colhidas de propriedades da região nordeste do Estado de São Paulo quanto aos parâmetros de composição, contagem de célula somática (CCS) e contagem bacteriana total (CBT), para verificar se as mesmas atenderiam ao estabelecido pela IN 62 e também averiguar a influência das estações do ano sobre tais parâmetros. Foram colhidas 1.716 amostras de leite cru direto dos tanques de expansão de 143 propriedades do Estado de São Paulo durante o ano de 2012 e realizadas as análises dos requisitos. De um total de 1.716 amostras avaliadas o período da primavera apresentou maiores índices de rejeição quanto os padrões para a IN 62 (69%), enquanto que os meses de outono apresentaram maiores números de amostras dentro do padrão (41%). Os resultados demonstraram que houve diferença significativa (P<0,05) entre as estações do ano, para os valores de gordura, proteína, lactose, extrato seco desengordurado, CCS e CBT. No período do outono os valores de gordura, proteína e ESD foram maiores. Em contrapartida os valores da CCS se apresentaram menores, período em que se têm menores índices de chuva... / As Brazil is increasingly producing more and more milk, there was greater concern about the quality of the milk and its derivatives. In 2011 the Normative Instruction 62 (IN 62) changed some articles of the Normative Instruction 51 (IN 51). Among the major changes, were on the somatic cell count (SCC) and total bacterial count (TBC). For producers to provide a quality product, companies alongside the federal government implemented programs for milk quality, which give bonus or penalize producers for the quality of milk produced. The present research, aimed to assess milk samples collected from properties of the northeast of the State of São Paulo for the composition of parameters, somatic cell count (SCC) and total bacterial count (TBC), to verify whether they meet the established by the IN 62 and also investigate the influence of the seasons on such parameters. 1,716 samples of raw milk were collected straight from the expansion tank of 143 properties in the State of São Paulo during the year 2012 and the analysis of such requirements were made. A total of 1,716 samples evaluated in the spring period had the highest rates of rejection as the standards for IN 62 (69%), while in the autumn months had the highest numbers of samples within the standard results (41%). The results showed that there was significant difference (P<0,05) between the seasons, for the values of fat, protein, lactose, defatted dry extract(DDE), SCC and TBC. During the autumn the values of fat, protein and DDE were higher. In contrast the values of SCC performed, for the period in which have lower levels of rain and the lactose did not suffer major changes. As for the payment of the milk the best receiving period was during the autumn months in that the fat and protein levels were high and the SCC lower. The SCC and TBC were the requirements that less fulfilled the... (Complete abstract click electronic access below)
100

Calibracao de um sistema de camara de ionizacao de poco 4'pi'-'gamma' para medidas de atividade de radio-nuclideos

DIAS, M.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:50:38Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T13:58:41Z (GMT). No. of bitstreams: 1 00830.pdf: 1838856 bytes, checksum: 0f6a3f75b210d4e73e342ebf7544cc17 (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP

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