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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.
51

Parâmetros genéticos para desempenho em corridas de cavalos puro sangue inglês utilizando procedimentos Bayesiano e Thurstoniano

Gama, Manuela Pires Monteiro da [UNESP] 25 May 2012 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:07Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-05-25Bitstream added on 2014-06-13T19:54:01Z : No. of bitstreams: 1 gama_mpm_me_jabo.pdf: 190063 bytes, checksum: b6fc2664d1583f57dbb78c9f59a29b61 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo desse trabalho foi estimar parâmetros genéticos para o caráter tempo e colocação final em corridas de cavalos Puro Sangue Inglês (PSI) com procedimentos Bayesiano e Thurstoniano, a fim de fornecer subsídios para a seleção de reprodutores e consequente melhoramento genético da raça no Brasil. A partir de dados fornecidos pela empresa Turf Total Ltda foram consideradas 251.754 informações de tempo e 272.277 informações de colocações finais em 34.316 corridas de cavalos PSI ocorridas entre 1992 e 2011 em 6 hipódromos do país, para as distâncias de 1.000, 1.300, 1.600 e 2.000 metros. Os efeitos considerados fixos foram idade, sexo, posição de largada e páreo para as análises de tempo, e sexo, idade, posição de largada, páreo e nível de dificuldade da corrida para as análises de colocações finais. As herdabilidades e correlações genéticas para tempo foram estimadas utilizando inferências bayesianas, ao passo que para as estimativas de herdabilidade de colocação final utilizou-se o modelo Thurstoniano. As estimativas de herdabilidade para tempo em análises unicaraterísticas. foram semelhantes às encontradas na literatura, e variaram entre 0,31 e 0,04 e as repetibilidades encontradas variaram de 0,61 a 0,22, respectivamente com o aumento das distâncias. As estimadas para colocação final variaram de 0,57 a 0,21, apresentando a mesma tendência que as herdabilidades para tempo. As estimativas de herdabilidade para tempo na análise multicaracterística variaram entre 0,34 e 0,15 com repetibilidade entre 0,63 e 0,36. Nessa análise, a seleção para tempo também mostrou-se mais eficiente em distâncias menores, onde as herdabilidades foram maiores. As estimativas de correlações genéticas foram positivas e variaram de 0,47 a 0,97. Conclui-se que, em distâncias mais curtas, a seleção tanto para tempo... / The objective of this study was to estimate genetic paremeters for racing time and final rank in Thoroughbred horses using Bayesian and Thurstonian procedures, in order to provide data that contribute for selection and the consequent genetic improvement of the breed in Brazil. Data were provided by the company Turf Total Ltda. and consisted of 251,754 racing time records and 272,277 final rank records obtained from 34,316 Thoroughbred races (distances of 1,000, 1,300, 1,600 and 2,000 m) that occurred between 1992 and 2011 on six race tracks. Fixed effects included age, sex, post-position and race for the analysis of racing time, and sex, age, post-position, race and level of difficulty for final rank analysis. The heritabilities for racing time and final rank and the genetic correlations between racing times were estimated by Bayesian inference. In addition, a Thurstonian model was used to estimate the heritability for final rank. The heritability estimates for racing time in one-trait analysis were similar to those reported in the literature and ranged from 0.31 to 0.04. Repeatability estimates tended to decrease with increasing race distance (0.61 to 0.22) .The heritabilities estimates for final rank ranged from 0.57 to 0.21 and showed the same trend as the heritabilities for time. The heritability estimates for racing time obtained by multi-trait analysis ranged form 0.34 to 0.15, with repeatabilities of 0.63 to 0.36 at the distances studied. Multi-trait analysis also showed that selection for racing time was more efficient at shorter distances when heritabilities were higher. The genetic correlations were all positive and ranged from 0.47 to 0.97. In conclusion, selection for both racing time and final rank is more efficient at shorter distances... (Complete abstract click electronic access below)
52

Estudo da tecnica de eletrodeposicao na preparacao de amostras para determinacao de U-233 por espectrometria alfa

MERTZIG, WERNER 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:31Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:14Z (GMT). No. of bitstreams: 1 00348.pdf: 1090339 bytes, checksum: 89d8cfffeb0919c6046af1f7251d14ae (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
53

Avaliação do programa paulista de colheita de amostra para análise de alimentos como contribuição da vigilância sanitária no estado de São Paulo /

Silvestre, Fernanda Perussi. January 2006 (has links)
Orientador: José Paschoal Batistuti / Banca: João Bosco Faria / Banca: Alceu Afonso Jordão Júnior / Resumo: Com a intensa produção e circulação de alimentos, os riscos à saúde ocorrem em escala ampliada e as conseqüências do consumo de produtos não conformes com a legislação sanitária, podem afetar a saúde de inúmeros consumidores, a credibilidade nos produtos e nas instituições de controle sanitário, além de provocar enormes prejuízos econômicos. Considerando o exposto, no ano de 1995, o Centro de Vigilância Sanitária juntamente com o Instituto Adolfo Lutz instituíram um Programa de Colheita de Amostras para Análise Fiscal de alimentos no Estado de São Paulo. Desde então, o Programa vem sendo aprimorado a cada ano e em 1998, recebeu o nome de Programa Paulista. Este trabalho teve como objetivo principal verificar as contribuições do Programa para a Saúde Pública Paulista. Para isso, foram utilizados os dados do Programa Paulista 2002 e do Programa Paulista Biênio 2003/2004. Com esse estudo foi possível observar grandes benefícios obtidos para a saúde dos consumidores através desta monitoração de qualidade de alimentos. / Abstract: Because of the intense production and circulation of foods, health risks occur in big scales and the consequences of the consumption of products that are not in conformity with sanitary laws can affect countless people, the credibility in products and institutions of sanitary control, besides bringing enormous economic impairments. Considering the exposed, in 1995, the Sanitary Vigilance Center in association with Adolfo Lutz Institute, created a Program of Food Samples Collection for “Análise Fiscal” in the state of São Paulo. Since then, the Program has been improved every year and in 1998 it was called as “Programa Paulista”. This work had the principal aim of verify the Program contributions for Public Health in the state of São Paulo. Then, the data of “Programa Paulista 2002” and “Programa Paulista 2003/2004” were used. This study allowed to observe big benefits on health consumers through monitoring food quality. / Mestre
54

Estudo da tecnica de eletrodeposicao na preparacao de amostras para determinacao de U-233 por espectrometria alfa

MERTZIG, WERNER 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:32:31Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:09:14Z (GMT). No. of bitstreams: 1 00348.pdf: 1090339 bytes, checksum: 89d8cfffeb0919c6046af1f7251d14ae (MD5) / Dissertacao (Mestrado) / IEA/D / Instituto de Energia Atomica - IEA
55

Development of sample pretreatment methods for complex analytical matrices

Ho, Yee Man 01 January 2013 (has links)
No description available.
56

Comparison of Denominator Degrees of Freedom Approximations for Linear Mixed Models in Small-Sample Simulations

January 2020 (has links)
abstract: Whilst linear mixed models offer a flexible approach to handle data with multiple sources of random variability, the related hypothesis testing for the fixed effects often encounters obstacles when the sample size is small and the underlying distribution for the test statistic is unknown. Consequently, five methods of denominator degrees of freedom approximations (residual, containment, between-within, Satterthwaite, Kenward-Roger) are developed to overcome this problem. This study aims to evaluate the performance of these five methods with a mixed model consisting of random intercept and random slope. Specifically, simulations are conducted to provide insights on the F-statistics, denominator degrees of freedom and p-values each method gives with respect to different settings of the sample structure, the fixed-effect slopes and the missing-data proportion. The simulation results show that the residual method performs the worst in terms of F-statistics and p-values. Also, Satterthwaite and Kenward-Roger methods tend to be more sensitive to the change of designs. The Kenward-Roger method performs the best in terms of F-statistics when the null hypothesis is true. / Dissertation/Thesis / Masters Thesis Statistics 2020
57

Sample Mislabeling Detection and Correction in Bioinformatics Experimental Data

Kho, Soon Jye 24 August 2021 (has links)
No description available.
58

Sample Size Determination in Multivariate Parameters With Applications to Nonuniform Subsampling in Big Data High Dimensional Linear Regression

Wang, Yu 12 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Subsampling is an important method in the analysis of Big Data. Subsample size determination (SSSD) plays a crucial part in extracting information from data and in breaking the challenges resulted from huge data sizes. In this thesis, (1) Sample size determination (SSD) is investigated in multivariate parameters, and sample size formulas are obtained for multivariate normal distribution. (2) Sample size formulas are obtained based on concentration inequalities. (3) Improved bounds for McDiarmid’s inequalities are obtained. (4) The obtained results are applied to nonuniform subsampling in Big Data high dimensional linear regression. (5) Numerical studies are conducted. The sample size formula in univariate normal distribution is a melody in elementary statistics. It appears that its generalization to multivariate normal (or more generally multivariate parameters) hasn’t been caught much attention to the best of our knowledge. In this thesis, we introduce a definition for SSD, and obtain explicit formulas for multivariate normal distribution, in gratifying analogy of the sample size formula in univariate normal. Commonly used concentration inequalities provide exponential rates, and sample sizes based on these inequalities are often loose. Talagrand (1995) provided the missing factor to sharpen these inequalities. We obtained the numeric values of the constants in the missing factor and slightly improved his results. Furthermore, we provided the missing factor in McDiarmid’s inequality. These improved bounds are used to give shrunken sample sizes.
59

Analysis of Inpatient Endometriosis and Associated Factors from the 2016-2020 National Inpatient Sample (NIS)

Rachwal, Brenna 06 June 2023 (has links)
No description available.
60

Addressing sample bias and representativeness at the Kinlock site (22SU526) a freshwater mussel shell ring in the Mississippi Delta

Mitchell, Joseph Alan 11 August 2012 (has links)
Applied zooarchaeology provides baselines which can be used in modern conservation biology to better understand how faunal communities have changed over time. This goal can only be accomplished, however, by first accounting for the multiple biases present within the archaeological record, and how they may affect sample representativeness. Taxonomic analysis was conducted on freshwater mussel shell from the late prehistoric (ca. A.D. 700 - 1200) Kinlock site, Sunflower County, Mississippi. Species-area curves and biodiversity indices demonstrate that random sampling of surface clusters of shell, up to about 4,000 valves, provides an adequate picture of the overall surface assemblage. Comparison of surface and subsurface contexts shows a highly significant difference in species numbers and proportions, indicating a need for multi-context sampling when dealing with archaeological shell deposits.

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