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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.
11

Modelagem matemática da eficiência de utilização da energia e da proteína dietéticas pelo pacu (Piaractus mesopotamicus Holmberg, 1887) / Mathematical modelling of the utilization efficiency of dietary energy and dietary protein by pacu (Piaractus mesopotamicus Holmberg, 1887)

Aguilar, Fredy Armando Aguilar 03 March 2016 (has links)
Sistemas intensivos de produção de peixes demandam o uso de dietas completas e manejo alimentar e nutricional precisos. O principal objetivo da nutrição dos peixes é melhorar a eficiência da utilização da energia e dos nutrientes da ração. Alta eficiência, na realidade, significa maior retenção de nutrientes e energia, i.e., maior crescimento, com menor descarga de nutrientes nos corpos d\'água. O objetivo deste trabalho foi estudar a eficiência de utilização da energia e a proteína da ração para o pacu, Piaractus mesopotamicus. Em um primeiro ensaio foram caracterizadas as propriedades físicoquímicas e os coeficientes de digestibilidade aparente da proteína e da energia de 28 amostras de rações para peixes onívoros comercializadas na região de Piracicaba, estado de São Paulo. Os dados obtidos foram utilizados no ajuste de modelos de regressão linear múltipla para predizer os conteúdos de energia digestível (ED) e proteína digestível (PD) das rações comerciais para a espécie. Uum segundo grupo de ensaios foi dedicado ao estudo da eficiência metabólica da utilização da energia e da proteína. Utilizando-se a técnica de respirometria de fluxo intermitente, foi quantificada a taxa metabólica padrão em peixes de diferente tamanho (17 g - 1050 g) em cinco temperaturas (19, 23, 26, 29 e 33°C). O coeficiente oxi-calórico para oxidação de gordura (13,72 J mg-1 O2) foi utilizado para converter os dados de consumo de oxigênio em taxas de produção de calor. O coeficiente alométrico da produção de calor em jejum foi próximo a 0,8, valor usual para outras espécies de peixes. A partir da aplicação do método fatorial de análise foram estimadas as exigências de energia digestível e proteína digestível para mantença e para o crescimento do pacu e o efeito do nível de lipídeos dietéticos (alto - AL, ou baixo - BL) sobre as exigências nutricionais. O nível de lipídeos da ração não influenciou a estimativa de exigência de energia para mantença (26,57 kJ de ED kg-0,8 dia-1 e 0,076 g de PD kg-0,7 dia-1). A exigência de energia digestível para crescimento (kJ de ED por kJ de energia retida) foi maior para a ração BL (1,387) do que para a ração AL (1,285). A exigência em proteína digestível (g de PD por g de proteína depositada) foi maior para peixes alimentados com a ração BL do que com a ração AL (1,7015 vs. 1,583). / Intensive fish farming systems entail the use of complete feeds and accurate feeding and nutrition management. The main objective of fish feeding and nutrition practices is the efficient use of feed energy and nutrients. High efficiency actually means increased retention of nutrients and energy, i.e., improved growth ratio and reduced discharge of nutrients in the water. This work aimed at studying the efficiency of use of feed energy and protein of pacu, Piaractus mesopotamicus. A first trial characterized physicochemical properties and apparent digestibility coefficients of protein and energy of 28 commercial, omnivorous fish feeds sampled in the region of Piracicaba, state of São Paulo. The data were used to set multiple linear regression models predicting the digestible energy (DE) and digestible protein (DP) contents of commercial, sampled feeds. A second group of trials studied the metabolic efficiency of use of energy and protein. The intermittent flow respirometry technique was used to quantify the standard metabolic rate of different fish size classes (17 g - 1050 g) at five temperatures (19, 23, 26, 29 and 33 ° C). The coefficient for oxy-caloric fat oxidation (13.72 J mg-1 O2) was used to convert the oxygen consumption data to heat production ratios. The allometric coefficient of heat production in fasting condition was 0.8, a typical value for other fish species. Digestible energy and digestible protein requirements for maintenance and growth and effects of dietary lipids (high - AL, or low - BL) contents on nutritional requirements of pacu were then studied with the aid of factorial analysis method. Dietary lipid contents did not affect energy requirements for maintenance (26.57 kJ DE kg-0.8 day-1 and 0.076 g DP kg-0.7 day-1). The digestible energy requirement for growth (kJ of ED per kJ of energy retained) was higher for BL feeds (1.387) than for AL feeds (1.285). The requirements of digestible protein (g DP per g of deposited protein) was higher for the BL than for the AL feed (1.7015 vs. 1.583).
12

Probabilistic Seismic Hazard Assessment Of Ilgaz - Abant Segments Of North Anatolian Fault Using Improved Seismic Source Models

Levendoglu, Mert 01 February 2013 (has links) (PDF)
Bolu-Ilgaz region was damaged by several large earthquakes in the last century and the structural damage was substantial especially after the 1944 and 1999 earthquakes. The objective of this study is to build the seismic source characterization model for the rupture zone of 1944 Bolu-Gerede earthquake and perform probabilistic seismic hazard assessment (PSHA) in the region. One of the major improvements over the previous PSHA practices accomplished in this study is the development of advanced seismic source models in terms of source geometry and reoccurrence relations. Geometry of the linear fault segments are determined and incorporated with the help of available fault maps. Composite magnitude distribution model is used to properly represent the characteristic behavior of NAF without an additional background zone. Fault segments, rupture sources, rupture scenarios and fault rupture models are determined using the WG-2003 terminology. The Turkey-Adjusted NGAW1 (G&uuml / lerce et al., 2013) prediction models are employed for the first time on NAF system. The results of the study is presented in terms of hazard curves, deaggregation of the hazard and uniform hazard spectrum for four main locations in the region to provide basis for evaluation of the seismic design of special structures in the area. Hazard maps of the region for rock site conditions and for the proposed site characterization model are provided to allow the user perform site-specific hazard assessment for local site conditions and develop site-specific design spectrum. The results of the study will be useful to manage the future seismic hazard in the region.
13

Probabilistic Seismic Hazard Assessment Of Eastern Marmara And Evaluation Of Turkish Earthquake Code Requirements

Ocak, Recai Soner 01 November 2011 (has links) (PDF)
The primary objective of this study is to evaluate the seismic hazard in the Eastern Marmara Region using improved seismic source models and enhanced ground motion prediction models by probabilistic approach. Geometry of the fault zones (length, width, dip angle, segmentation points etc.) is determined by the help of available fault maps and traced source lines on the satellite images. State of the art rupture model proposed by USGS Working Group in 2002 is applied to the source system. Composite reoccurrence model is used for all seismic sources in the region to represent the characteristic behavior of North Anatolian Fault. New and improved global ground motion models (NGA models) are used to model the ground motion variability for this study. Previous studies, in general, used regional models or older ground motion prediction models which were updated by their developers during the NGA project. New NGA models were improved in terms of additional prediction parameters (such as depth of the source, basin effects, site dependent standard deviations, etc.), statistical approach, and very well constrained global database. The use of NGA models reduced the epistemic uncertainty in the total hazard incorporated by regional or older models using smaller datasets. The results of the study is presented in terms of hazard curves, deaggregation of the hazard and uniform hazard spectrum for six main locations in the region (Adapazari, Duzce, Golcuk, Izmit, Iznik, and Sapanca City Centers) to provide basis for seismic design of special structures in the area. Hazard maps of the region for rock site conditions at the accepted levels of risk by Turkish Earthquake Code (TEC-2007) are provided to allow the user perform site-specific hazard assessment for local site conditions and develop site-specific design spectrum. Comparison of TEC-2007 design spectrum with the uniform hazard spectrum developed for selected locations is also presented for future reference.
14

Producing in-house pureed food in long-term care

Ilhamto, Nila 11 January 2013 (has links)
There is limited knowledge on provisions used to ensure swallowing safety, nutritional adequacy and sensory acceptability of pureed foods in long-term care homes (LTCHs). The overall aim for this research was to expand knowledge of pureed food production in LTCHs, to study the impact of varying ingredients and preparation on sensory and nutrition and to model perceived oral textures in pureed food. Qualitative interviews with dietary staff (n=53) in 25 LTCHs showed a variety of challenges and practices in production, affecting overall quality. Pureed turkey varying in added liquid, meat muscle and seasoning method and pureed carrots varying in thickener type were evaluated by a descriptive sensory panel (n=10). Results indicate that small formulation changes can have a significant impact on the nutrition and sensory properties of pureed food. Instrumental tests using a viscometer, line-spread test and texture analyzer showed different strengths in predicting variation in orally-perceived textures. / Funding for this project has been provided by Agriculture and Agri-Food Canada through the Canadian Agricultural Adaptation Program (CAAP). In Ontario, this program is delivered by the Agricultural Adaptation Council (AAC).
15

Determinação do gasto energético de pacientes com doença pulmonar obstrutiva crônica : comparação entre dois métodos de avaliação

Muttoni, Sandra Maria Pazzini January 2010 (has links)
Introdução: O gasto energético (GE) dos indivíduos pode ser determinado por diversos métodos, dentre os quais estão a calorimetria indireta (CI) e as equações de predição. Objetivo: Comparar o gasto energético de pacientes com doença pulmonar obstrutiva crônica (DPOC) medido através da CI com o estimado pela equação de Harris-Benedict (HB). Métodos: Estudo transversal incluindo 30 indivíduos com diagnóstico médico de DPOC, segundo critérios GOLD, atendidos no Centro de Reabilitação Pulmonar do Pavilhão Pereira Filho e do ambulatório de Pneumologia, ambos do Complexo Hospitalar Santa Casa de Porto Alegre, no período de fevereiro à setembro de 2010. O gasto energético foi mensurado pela CI usando monitor específico, assim como predito pela equação de HB. Os participantes também foram submetidos à avaliação antropométrica, através dos parâmetros de peso, altura, índice de massa corporal (IMC), dobra cutânea tricipital (DCT), circunferência do braço (CB) e circunferência muscular do braço (CMB), além de aplicação da avaliação nutricional subjetiva global (ANSG), bem como verificação do consumo alimentar. Os valores encontrados foram analisados através do teste t de Student, do teste qui-quadrado de McNemar e pelo método de Bland-Altman, e expressos pela média ± desvio-padrão, com nível de significância estatística p 0,05. Resultados: Do total de 30 portadores de DPOC, 70% eram do sexo masculino com idades de 62,5 ± 11,5 anos e IMC médio de 24,2 ± 4,2kg/m². O gasto energético em repouso (GER) medido pela CI foi de 1.568 ± 234,8kcal e o estimado pela equação de HB foi de 1.312 ± 120,5kcal, com diferença estatisticamente significativa entre os dois métodos (p<0,001). Quanto ao gasto energético total (GET), o valor medido pela CI foi de 2.038 ± 305,23kcal e o predito pela equação de HB foi de 2.047 ± 188kcal, sem apresentar diferença estatística significativa (p=0,853) e demonstrando uma concordância de 96,7% entre os dois métodos. Relativo ao diagnóstico nutricional, ao considerarmos apenas o IMC, 3,3% dos participantes apresentavam desnutrição, 63,3% eutrofia, 23,3% sobrepeso e 10% obesidade enquanto que pelo agrupamento de parâmetros (IMC, DCT, CB, CMB e ANSG), 53,3% dos pacientes apresentaram desnutrição, 33,3% eutrofia, 10% sobrepeso e 3,3% obesidade. Conclusão: O GER foi subestimado pela equação de HB, não apresentando boa concordância com o medido pela CI. Quanto ao GET, os resultados foram significativamente semelhantes demonstrando boa concordância entre os dois métodos. Em relação ao estado nutricional, talvez o IMC não seja suficiente para avaliar a real condição de pacientes com DPOC. / Introduction: The energy expenditure (EE) of individuals can be determined by various methods, among which are the indirect calorimetry (IC) and the prediction equations. Objective: To compare the energy expenditure of patients with chronic obstructive pulmonary disease (COPD) measured by the IC estimate by the Harris-Benedict equation (HB). Methods: Cross sectional study including 30 individuals diagnosed with COPD according to GOLD criteria, seen in the Pulmonary Rehabilitation Center of the Pereira Filho and outpatient pulmonology, both of Santa Casa Hospital Complex of Porto Alegre in the period from February to September 2010. Energy expenditure was measured by IC using a specific monitor, as predicted by the HB equation. Participants also underwent anthropometric assessment, through the parameters of weight, height, body mass index (BMI), triceps skinfold thickness (TSF), mid-arm circumference (MAC) and mid-arm muscle circumference (MAMC), and application subjective global nutritional assessment (SGA) and to determine food consumption. The values were analyzed using the Student t test, chi-square, McNemar and the Bland-Altman and expressed as mean + standart deviation, with statistical significance level p 0.05. Results: Of 30 patients with COPD, 70% were male, aged 62.5 ± 11.5 years and average BMI of 24.2 ± 4.2kg/m². The resting energy expenditure (REE) measured by IC was 1568 ± 234.8kcal and estimated by the HB equation was 1312 ± 120.5kcal, with a statistically significant difference between the two methods (p<0.001). As for the total energy expenditure (TEE), the value measured by ICwo methods (p <0.001). As for the total energy expenditure (TEE), the value measured by IC was 2038 ± 305.23kcal and foretold the HB equation was 2047 ± 188kcal, no statistical significant difference (p=0.853) and showed a concordance of 96,7% between the two methods. Concerning the nutritional diagnosis, we consider only the BMI, 3.3% of participants had malnutrition, 63.3% were eutrophic, 23.3% overweight and 10% were obese while the grouping of parameters (BMI, TSF, CB, CMB and SGA), 53.3% of patients suffered from malnutrion, 33.3% were eutrophic, 10% overweight and 3.3% obese. Conclusion: REE was underestimated by the HB equation, not a good agreement with that measured by IC. As for the GET, the results were significantly similar showing good agreement between the two methods. In relation to nutritional status, BMI may not be sufficient to evaluate the actual condition of patients with COPD.
16

Determinação do gasto energético de pacientes com doença pulmonar obstrutiva crônica : comparação entre dois métodos de avaliação

Muttoni, Sandra Maria Pazzini January 2010 (has links)
Introdução: O gasto energético (GE) dos indivíduos pode ser determinado por diversos métodos, dentre os quais estão a calorimetria indireta (CI) e as equações de predição. Objetivo: Comparar o gasto energético de pacientes com doença pulmonar obstrutiva crônica (DPOC) medido através da CI com o estimado pela equação de Harris-Benedict (HB). Métodos: Estudo transversal incluindo 30 indivíduos com diagnóstico médico de DPOC, segundo critérios GOLD, atendidos no Centro de Reabilitação Pulmonar do Pavilhão Pereira Filho e do ambulatório de Pneumologia, ambos do Complexo Hospitalar Santa Casa de Porto Alegre, no período de fevereiro à setembro de 2010. O gasto energético foi mensurado pela CI usando monitor específico, assim como predito pela equação de HB. Os participantes também foram submetidos à avaliação antropométrica, através dos parâmetros de peso, altura, índice de massa corporal (IMC), dobra cutânea tricipital (DCT), circunferência do braço (CB) e circunferência muscular do braço (CMB), além de aplicação da avaliação nutricional subjetiva global (ANSG), bem como verificação do consumo alimentar. Os valores encontrados foram analisados através do teste t de Student, do teste qui-quadrado de McNemar e pelo método de Bland-Altman, e expressos pela média ± desvio-padrão, com nível de significância estatística p 0,05. Resultados: Do total de 30 portadores de DPOC, 70% eram do sexo masculino com idades de 62,5 ± 11,5 anos e IMC médio de 24,2 ± 4,2kg/m². O gasto energético em repouso (GER) medido pela CI foi de 1.568 ± 234,8kcal e o estimado pela equação de HB foi de 1.312 ± 120,5kcal, com diferença estatisticamente significativa entre os dois métodos (p<0,001). Quanto ao gasto energético total (GET), o valor medido pela CI foi de 2.038 ± 305,23kcal e o predito pela equação de HB foi de 2.047 ± 188kcal, sem apresentar diferença estatística significativa (p=0,853) e demonstrando uma concordância de 96,7% entre os dois métodos. Relativo ao diagnóstico nutricional, ao considerarmos apenas o IMC, 3,3% dos participantes apresentavam desnutrição, 63,3% eutrofia, 23,3% sobrepeso e 10% obesidade enquanto que pelo agrupamento de parâmetros (IMC, DCT, CB, CMB e ANSG), 53,3% dos pacientes apresentaram desnutrição, 33,3% eutrofia, 10% sobrepeso e 3,3% obesidade. Conclusão: O GER foi subestimado pela equação de HB, não apresentando boa concordância com o medido pela CI. Quanto ao GET, os resultados foram significativamente semelhantes demonstrando boa concordância entre os dois métodos. Em relação ao estado nutricional, talvez o IMC não seja suficiente para avaliar a real condição de pacientes com DPOC. / Introduction: The energy expenditure (EE) of individuals can be determined by various methods, among which are the indirect calorimetry (IC) and the prediction equations. Objective: To compare the energy expenditure of patients with chronic obstructive pulmonary disease (COPD) measured by the IC estimate by the Harris-Benedict equation (HB). Methods: Cross sectional study including 30 individuals diagnosed with COPD according to GOLD criteria, seen in the Pulmonary Rehabilitation Center of the Pereira Filho and outpatient pulmonology, both of Santa Casa Hospital Complex of Porto Alegre in the period from February to September 2010. Energy expenditure was measured by IC using a specific monitor, as predicted by the HB equation. Participants also underwent anthropometric assessment, through the parameters of weight, height, body mass index (BMI), triceps skinfold thickness (TSF), mid-arm circumference (MAC) and mid-arm muscle circumference (MAMC), and application subjective global nutritional assessment (SGA) and to determine food consumption. The values were analyzed using the Student t test, chi-square, McNemar and the Bland-Altman and expressed as mean + standart deviation, with statistical significance level p 0.05. Results: Of 30 patients with COPD, 70% were male, aged 62.5 ± 11.5 years and average BMI of 24.2 ± 4.2kg/m². The resting energy expenditure (REE) measured by IC was 1568 ± 234.8kcal and estimated by the HB equation was 1312 ± 120.5kcal, with a statistically significant difference between the two methods (p<0.001). As for the total energy expenditure (TEE), the value measured by ICwo methods (p <0.001). As for the total energy expenditure (TEE), the value measured by IC was 2038 ± 305.23kcal and foretold the HB equation was 2047 ± 188kcal, no statistical significant difference (p=0.853) and showed a concordance of 96,7% between the two methods. Concerning the nutritional diagnosis, we consider only the BMI, 3.3% of participants had malnutrition, 63.3% were eutrophic, 23.3% overweight and 10% were obese while the grouping of parameters (BMI, TSF, CB, CMB and SGA), 53.3% of patients suffered from malnutrion, 33.3% were eutrophic, 10% overweight and 3.3% obese. Conclusion: REE was underestimated by the HB equation, not a good agreement with that measured by IC. As for the GET, the results were significantly similar showing good agreement between the two methods. In relation to nutritional status, BMI may not be sufficient to evaluate the actual condition of patients with COPD.
17

Determinação do gasto energético de pacientes com doença pulmonar obstrutiva crônica : comparação entre dois métodos de avaliação

Muttoni, Sandra Maria Pazzini January 2010 (has links)
Introdução: O gasto energético (GE) dos indivíduos pode ser determinado por diversos métodos, dentre os quais estão a calorimetria indireta (CI) e as equações de predição. Objetivo: Comparar o gasto energético de pacientes com doença pulmonar obstrutiva crônica (DPOC) medido através da CI com o estimado pela equação de Harris-Benedict (HB). Métodos: Estudo transversal incluindo 30 indivíduos com diagnóstico médico de DPOC, segundo critérios GOLD, atendidos no Centro de Reabilitação Pulmonar do Pavilhão Pereira Filho e do ambulatório de Pneumologia, ambos do Complexo Hospitalar Santa Casa de Porto Alegre, no período de fevereiro à setembro de 2010. O gasto energético foi mensurado pela CI usando monitor específico, assim como predito pela equação de HB. Os participantes também foram submetidos à avaliação antropométrica, através dos parâmetros de peso, altura, índice de massa corporal (IMC), dobra cutânea tricipital (DCT), circunferência do braço (CB) e circunferência muscular do braço (CMB), além de aplicação da avaliação nutricional subjetiva global (ANSG), bem como verificação do consumo alimentar. Os valores encontrados foram analisados através do teste t de Student, do teste qui-quadrado de McNemar e pelo método de Bland-Altman, e expressos pela média ± desvio-padrão, com nível de significância estatística p 0,05. Resultados: Do total de 30 portadores de DPOC, 70% eram do sexo masculino com idades de 62,5 ± 11,5 anos e IMC médio de 24,2 ± 4,2kg/m². O gasto energético em repouso (GER) medido pela CI foi de 1.568 ± 234,8kcal e o estimado pela equação de HB foi de 1.312 ± 120,5kcal, com diferença estatisticamente significativa entre os dois métodos (p<0,001). Quanto ao gasto energético total (GET), o valor medido pela CI foi de 2.038 ± 305,23kcal e o predito pela equação de HB foi de 2.047 ± 188kcal, sem apresentar diferença estatística significativa (p=0,853) e demonstrando uma concordância de 96,7% entre os dois métodos. Relativo ao diagnóstico nutricional, ao considerarmos apenas o IMC, 3,3% dos participantes apresentavam desnutrição, 63,3% eutrofia, 23,3% sobrepeso e 10% obesidade enquanto que pelo agrupamento de parâmetros (IMC, DCT, CB, CMB e ANSG), 53,3% dos pacientes apresentaram desnutrição, 33,3% eutrofia, 10% sobrepeso e 3,3% obesidade. Conclusão: O GER foi subestimado pela equação de HB, não apresentando boa concordância com o medido pela CI. Quanto ao GET, os resultados foram significativamente semelhantes demonstrando boa concordância entre os dois métodos. Em relação ao estado nutricional, talvez o IMC não seja suficiente para avaliar a real condição de pacientes com DPOC. / Introduction: The energy expenditure (EE) of individuals can be determined by various methods, among which are the indirect calorimetry (IC) and the prediction equations. Objective: To compare the energy expenditure of patients with chronic obstructive pulmonary disease (COPD) measured by the IC estimate by the Harris-Benedict equation (HB). Methods: Cross sectional study including 30 individuals diagnosed with COPD according to GOLD criteria, seen in the Pulmonary Rehabilitation Center of the Pereira Filho and outpatient pulmonology, both of Santa Casa Hospital Complex of Porto Alegre in the period from February to September 2010. Energy expenditure was measured by IC using a specific monitor, as predicted by the HB equation. Participants also underwent anthropometric assessment, through the parameters of weight, height, body mass index (BMI), triceps skinfold thickness (TSF), mid-arm circumference (MAC) and mid-arm muscle circumference (MAMC), and application subjective global nutritional assessment (SGA) and to determine food consumption. The values were analyzed using the Student t test, chi-square, McNemar and the Bland-Altman and expressed as mean + standart deviation, with statistical significance level p 0.05. Results: Of 30 patients with COPD, 70% were male, aged 62.5 ± 11.5 years and average BMI of 24.2 ± 4.2kg/m². The resting energy expenditure (REE) measured by IC was 1568 ± 234.8kcal and estimated by the HB equation was 1312 ± 120.5kcal, with a statistically significant difference between the two methods (p<0.001). As for the total energy expenditure (TEE), the value measured by ICwo methods (p <0.001). As for the total energy expenditure (TEE), the value measured by IC was 2038 ± 305.23kcal and foretold the HB equation was 2047 ± 188kcal, no statistical significant difference (p=0.853) and showed a concordance of 96,7% between the two methods. Concerning the nutritional diagnosis, we consider only the BMI, 3.3% of participants had malnutrition, 63.3% were eutrophic, 23.3% overweight and 10% were obese while the grouping of parameters (BMI, TSF, CB, CMB and SGA), 53.3% of patients suffered from malnutrion, 33.3% were eutrophic, 10% overweight and 3.3% obese. Conclusion: REE was underestimated by the HB equation, not a good agreement with that measured by IC. As for the GET, the results were significantly similar showing good agreement between the two methods. In relation to nutritional status, BMI may not be sufficient to evaluate the actual condition of patients with COPD.
18

Modelagem matemática da eficiência de utilização da energia e da proteína dietéticas pelo pacu (Piaractus mesopotamicus Holmberg, 1887) / Mathematical modelling of the utilization efficiency of dietary energy and dietary protein by pacu (Piaractus mesopotamicus Holmberg, 1887)

Fredy Armando Aguilar Aguilar 03 March 2016 (has links)
Sistemas intensivos de produção de peixes demandam o uso de dietas completas e manejo alimentar e nutricional precisos. O principal objetivo da nutrição dos peixes é melhorar a eficiência da utilização da energia e dos nutrientes da ração. Alta eficiência, na realidade, significa maior retenção de nutrientes e energia, i.e., maior crescimento, com menor descarga de nutrientes nos corpos d\'água. O objetivo deste trabalho foi estudar a eficiência de utilização da energia e a proteína da ração para o pacu, Piaractus mesopotamicus. Em um primeiro ensaio foram caracterizadas as propriedades físicoquímicas e os coeficientes de digestibilidade aparente da proteína e da energia de 28 amostras de rações para peixes onívoros comercializadas na região de Piracicaba, estado de São Paulo. Os dados obtidos foram utilizados no ajuste de modelos de regressão linear múltipla para predizer os conteúdos de energia digestível (ED) e proteína digestível (PD) das rações comerciais para a espécie. Uum segundo grupo de ensaios foi dedicado ao estudo da eficiência metabólica da utilização da energia e da proteína. Utilizando-se a técnica de respirometria de fluxo intermitente, foi quantificada a taxa metabólica padrão em peixes de diferente tamanho (17 g - 1050 g) em cinco temperaturas (19, 23, 26, 29 e 33°C). O coeficiente oxi-calórico para oxidação de gordura (13,72 J mg-1 O2) foi utilizado para converter os dados de consumo de oxigênio em taxas de produção de calor. O coeficiente alométrico da produção de calor em jejum foi próximo a 0,8, valor usual para outras espécies de peixes. A partir da aplicação do método fatorial de análise foram estimadas as exigências de energia digestível e proteína digestível para mantença e para o crescimento do pacu e o efeito do nível de lipídeos dietéticos (alto - AL, ou baixo - BL) sobre as exigências nutricionais. O nível de lipídeos da ração não influenciou a estimativa de exigência de energia para mantença (26,57 kJ de ED kg-0,8 dia-1 e 0,076 g de PD kg-0,7 dia-1). A exigência de energia digestível para crescimento (kJ de ED por kJ de energia retida) foi maior para a ração BL (1,387) do que para a ração AL (1,285). A exigência em proteína digestível (g de PD por g de proteína depositada) foi maior para peixes alimentados com a ração BL do que com a ração AL (1,7015 vs. 1,583). / Intensive fish farming systems entail the use of complete feeds and accurate feeding and nutrition management. The main objective of fish feeding and nutrition practices is the efficient use of feed energy and nutrients. High efficiency actually means increased retention of nutrients and energy, i.e., improved growth ratio and reduced discharge of nutrients in the water. This work aimed at studying the efficiency of use of feed energy and protein of pacu, Piaractus mesopotamicus. A first trial characterized physicochemical properties and apparent digestibility coefficients of protein and energy of 28 commercial, omnivorous fish feeds sampled in the region of Piracicaba, state of São Paulo. The data were used to set multiple linear regression models predicting the digestible energy (DE) and digestible protein (DP) contents of commercial, sampled feeds. A second group of trials studied the metabolic efficiency of use of energy and protein. The intermittent flow respirometry technique was used to quantify the standard metabolic rate of different fish size classes (17 g - 1050 g) at five temperatures (19, 23, 26, 29 and 33 ° C). The coefficient for oxy-caloric fat oxidation (13.72 J mg-1 O2) was used to convert the oxygen consumption data to heat production ratios. The allometric coefficient of heat production in fasting condition was 0.8, a typical value for other fish species. Digestible energy and digestible protein requirements for maintenance and growth and effects of dietary lipids (high - AL, or low - BL) contents on nutritional requirements of pacu were then studied with the aid of factorial analysis method. Dietary lipid contents did not affect energy requirements for maintenance (26.57 kJ DE kg-0.8 day-1 and 0.076 g DP kg-0.7 day-1). The digestible energy requirement for growth (kJ of ED per kJ of energy retained) was higher for BL feeds (1.387) than for AL feeds (1.285). The requirements of digestible protein (g DP per g of deposited protein) was higher for the BL than for the AL feed (1.7015 vs. 1.583).
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évaluation du risque sismique par approches neuronales / a framework for seismic risk assessment based on artificial neural networks

Wang, Zhiyi 27 November 2018 (has links)
L'étude probabiliste de sûreté (EPS) parasismique est l'une des méthodologies les plus utiliséespour évaluer et assurer la performance des infrastructures critiques, telles que les centrales nucléaires,sous excitations sismiques. La thèse discute sur les aspects suivants: (i) Construction de méta-modèlesavec les réseaux de neurones pour construire les relations entre les intensités sismiques et les paramètresde demande des structures, afin d'accélérer l'analyse de fragilité. L'incertitude liée à la substitution desmodèles des éléments finis par les réseaux de neurones est étudiée. (ii) Proposition d'une méthodologiebayésienne avec réseaux de neurones adaptatifs, afin de prendre en compte les différentes sourcesd'information, y compris les résultats des simulations numériques, les valeurs de référence fournies dansla littérature et les évaluations post-sismiques, dans le calcul de courbes de fragilité. (iii) Calcul des loisd'atténuation avec les réseaux de neurones. Les incertitudes épistémiques des paramètres d'entrée de loisd'atténuation, tels que la magnitude et la vitesse moyenne des ondes de cisaillement de trente mètres, sontprises en compte dans la méthodologie développée. (iv) Calcul du taux de défaillance annuel en combinantles résultats des analyses de fragilité et de l'aléa sismique. Les courbes de fragilité sont déterminées parle réseau de neurones adaptatif, tandis que les courbes d'aléa sont obtenues à partir des lois d'atténuationconstruites avec les réseaux de neurones. Les méthodologies proposées sont appliquées à plusieurs casindustriels, tels que le benchmark KARISMA et le modèle SMART. / Seismic probabilistic risk assessment (SPRA) is one of the most widely used methodologiesto assess and to ensure the performance of critical infrastructures, such as nuclear power plants (NPPs),faced with earthquake events. SPRA adopts a probabilistic approach to estimate the frequency ofoccurrence of severe consequences of NPPs under seismic conditions. The thesis provides discussionson the following aspects: (i) Construction of meta-models with ANNs to build the relations betweenseismic IMs and engineering demand parameters of the structures, for the purpose of accelerating thefragility analysis. The uncertainty related to the substitution of FEMs models by ANNs is investigated.(ii) Proposal of a Bayesian-based framework with adaptive ANNs, to take into account different sourcesof information, including numerical simulation results, reference values provided in the literature anddamage data obtained from post-earthquake observations, in the fragility analysis. (iii) Computation ofGMPEs with ANNs. The epistemic uncertainties of the GMPE input parameters, such as the magnitudeand the averaged thirty-meter shear wave velocity, are taken into account in the developed methodology.(iv) Calculation of the annual failure rate by combining results from the fragility and hazard analyses.The fragility curves are determined by the adaptive ANN, whereas the hazard curves are obtained fromthe GMPEs calibrated with ANNs. The proposed methodologies are applied to various industrial casestudies, such as the KARISMA benchmark and the SMART model.
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Prochaine generation paneuropéennes équations de prédiction de mouvements de terrains pour les paramêtres de ingénierie / Next generation pan-european ground-motion prediction equations for engineering parameters

Sandikkaya, Mustafa Abdullah 11 April 2014 (has links)
Cette étude présente tout d'abord la récente banque de données fort mouvement pan-européen qui est mis à jour et la version étendue de bases de données paneuropéennes précédentes. Les métadonnées relatives est soigneusement compilé et réévalué. La base de données est conforme aux normes élevées pour être des ressources de la communauté paneuropéenne de génie parasismique. Ensuite, une étude empirique non linéaire place amplification modèle, fonction de la moyenne en fonction du temps de la plus haute 30m profil de vitesse des ondes de cisaillement et l'accélération maximale du sol sur le roc, est développé. L'objectif principal de tirer un tel modèle est de l'utiliser dans les équations de prédiction des mouvements du sol (GMPEs). Par ailleurs, l'évaluation des facteurs de site dans les codes de conception parasismique montre qu'il est également applicable dans les facteurs de sites informatiques. À cette fin, une autre méthodologie qui prend en compte les résultats de l'analyse de l'aléa sismique probabiliste et déterministe modèles de site est proposé. Cette étude génère GMPEs de réponse élastique ordonnées spectrales horizontale et verticale d'amortissement de 5%. Plutôt que d'équations directs pour le mouvement vertical, afin d'obtenir spectre du danger horizontale et verticale cohérente, compatible GMPE de rapport vertical à horizontal est préférable. Modèles de mise à l'échelle d'amortissement supplémentaires pour modifier les spectres horizontaux et verticaux d'autres ratios d'amortissement sont proposées. / This study firstly presents the recent pan-European strong-motion databank that is updated and extended version of previous pan-European databases. The pertaining metadata is carefully compiled and reappraised. The database meets high standards for being resource of pan-European earthquake engineering community. Then, an empirical nonlinear site amplification model, function of time-based average of uppermost 30m shear wave velocity profile and peak ground acceleration on rock, is developed. The primary aim of deriving such a model is to use it in ground motion prediction equations (GMPEs). Besides, the evaluation of site factors in the seismic design codes shows that it is also applicable in computing site factors. To this end, an alternative methodology that considers the results of probabilistic seismic hazard analysis and deterministic site models is proposed. Finally, this study generates GMPEs for horizontal and vertical elastic response spectral ordinates for different damping values between 1% to 50%. Rather than direct equations for vertical motion, to obtain consistent horizontal and vertical hazard spectrum, compatible vertical-to-horizontal ratio GMPE is preferred. Additional damping scaling models to modify horizontal and vertical spectra at other damping ratios are proposed

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