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The Analysis of Implied Default Point under the Barrier OptionFramework -An Application of Variance Gamma ProcessYang, Chao-chih 02 July 2010 (has links)
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Seitlicher Überholabstand von Radfahrern durch den motorisierten Verkehr – Empirische Analyse mit Hilfe von KameradatenLanger, Ralf 05 January 2017 (has links) (PDF)
Die Sicherheit des Radverkehrs im innerstädtischen Kontext ist ein bedeutsames Thema. Bislang konzentrierte sich die Betrachtung fast immer nur auf das Unfallgeschehen an Knotenpunkten. Der Bereich der freien Strecke hinsichtlich der Gefährdung der Radfahrer durch überholende Fahrzeuge wurde bisher kaum einbezogen und daher wenig erforscht. Die Arbeit widmet sich der Untersuchung von Abständen beim Überholen von Radfahrern durch motorisierte Fahrzeuge. Zu Beginn wird die Hypothese aufgestellt, dass die in der Praxis auftretenden Sicherheitsabstände zwischen Fahrzeugen und Radfahrern geringer sind, als die planerisch und rechtlich vorgegebenen Werte. In einem Feldversuch wurden mit einem eigens entwickelten Messverfahren Daten empirisch erhoben und statistisch ausgewertet. Frühere Forschungsarbeiten und geltende Regelwerke sowie rechtliche Festlegungen dienten anschließend als Grundlage und Vergleichsbasis bei der Einschätzung der empirischen Daten. Diese wurden im Messverfahren durch Videoaufnahmen ermittelt. Dabei zeigte sich, dass die gemessenen Werte im Mittel so gut wie immer unter den rechtlich und planerisch angegebenen Werten lagen. Die Fahrzeugführer neigten zu geringen und teilweise zu gefährlichen Sicherheitsabständen. In der Untersuchung wirkten verschiedenste Einflussfaktoren auf die Messdaten. Es konnte herausgefunden werden, dass beispielsweise das Vorhandensein von Gegenverkehr einen entscheidenden Einfluss auf die Größe des gewählten Abstands hat. / The safety of cycle traffic in urban areas is an important topic. Until now contemplation almost always focused on accident occurances on junctions only. The range of free haul and its danger for cyclists resulting from overtaking vehicles have barely been incorporated and are thus underexplored. This dissertation is dedicated to the observation of safety distances of motorized vehicles, when overtaking cyclists. At the beginning, the assumption is, that the safety margins between vehicles and cyclists, occuring in the field, are smaller than the legitimately predetermined values. With the help of a specially developed measurement method, data was empirical collected and statistically analysed in a field trial. Former researches, valid sets of rules and legal commitments served as a fundament as well as a basis of comparison for the evaluation of empirical data, which was determined by measuring methodes through video footage. It was found that the measured values were almost always below the legally given values and vehicle operators even tended to dangerously reduce their safety margins. During the study, it became obvious that different factors had an effect on the measurement data.
For example the decisive influence of oncoming traffic on the amount of clearance.
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Seitlicher Überholabstand von Radfahrern durch den motorisierten Verkehr – Empirische Analyse mit Hilfe von KameradatenLanger, Ralf 07 March 2016 (has links)
Die Sicherheit des Radverkehrs im innerstädtischen Kontext ist ein bedeutsames Thema. Bislang konzentrierte sich die Betrachtung fast immer nur auf das Unfallgeschehen an Knotenpunkten. Der Bereich der freien Strecke hinsichtlich der Gefährdung der Radfahrer durch überholende Fahrzeuge wurde bisher kaum einbezogen und daher wenig erforscht. Die Arbeit widmet sich der Untersuchung von Abständen beim Überholen von Radfahrern durch motorisierte Fahrzeuge. Zu Beginn wird die Hypothese aufgestellt, dass die in der Praxis auftretenden Sicherheitsabstände zwischen Fahrzeugen und Radfahrern geringer sind, als die planerisch und rechtlich vorgegebenen Werte. In einem Feldversuch wurden mit einem eigens entwickelten Messverfahren Daten empirisch erhoben und statistisch ausgewertet. Frühere Forschungsarbeiten und geltende Regelwerke sowie rechtliche Festlegungen dienten anschließend als Grundlage und Vergleichsbasis bei der Einschätzung der empirischen Daten. Diese wurden im Messverfahren durch Videoaufnahmen ermittelt. Dabei zeigte sich, dass die gemessenen Werte im Mittel so gut wie immer unter den rechtlich und planerisch angegebenen Werten lagen. Die Fahrzeugführer neigten zu geringen und teilweise zu gefährlichen Sicherheitsabständen. In der Untersuchung wirkten verschiedenste Einflussfaktoren auf die Messdaten. Es konnte herausgefunden werden, dass beispielsweise das Vorhandensein von Gegenverkehr einen entscheidenden Einfluss auf die Größe des gewählten Abstands hat. / The safety of cycle traffic in urban areas is an important topic. Until now contemplation almost always focused on accident occurances on junctions only. The range of free haul and its danger for cyclists resulting from overtaking vehicles have barely been incorporated and are thus underexplored. This dissertation is dedicated to the observation of safety distances of motorized vehicles, when overtaking cyclists. At the beginning, the assumption is, that the safety margins between vehicles and cyclists, occuring in the field, are smaller than the legitimately predetermined values. With the help of a specially developed measurement method, data was empirical collected and statistically analysed in a field trial. Former researches, valid sets of rules and legal commitments served as a fundament as well as a basis of comparison for the evaluation of empirical data, which was determined by measuring methodes through video footage. It was found that the measured values were almost always below the legally given values and vehicle operators even tended to dangerously reduce their safety margins. During the study, it became obvious that different factors had an effect on the measurement data.
For example the decisive influence of oncoming traffic on the amount of clearance.
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Effect of antibiotics in goat milk on the manufacture and characteristics of cheeseQuintanilla Vázquez, Paloma Galicia 02 July 2020 (has links)
Tesis por compendio / [ES] Los residuos de antibióticos en la leche constituyen un aspecto de gran importancia para la salud pública y pueden tener un efecto negativo en la industria láctea. Para proteger al consumidor se han establecido los Límites Máximos de Residuos (LMR) para diferentes antibióticos en la leche cruda. Sin embargo, la transferencia de estas sustancias de la leche al queso ha sido poco estudiada y, por lo tanto, se desconoce el impacto de la presencia de antibióticos sobre el proceso de elaboración y la seguridad del queso.
El objetivo de la tesis ha sido evaluar la transferencia de los antibióticos más empleados en el ganado caprino lechero, desde la leche a quesos curados y frescos, así como estudiar el efecto sobre el proceso de fabricación y la calidad de los quesos durante la maduración.
Para alcanzar el objetivo se han realizado elaboraciones de quesos curados (60 días) a partir de leche en presencia de diversos antibióticos (amoxicilina, bencilpenicilina, cloxacilina, eritromicina, ciprofloxacina, enrofloxacina y oxitetraciclina) a niveles admisibles (LMR) y fabricaciones de leche libre de antibiótico como referencia. Los resultados obtenidos sugieren que la mayor parte de los antibióticos en la leche no afectaron al proceso de fabricación del queso. Solamente la eritromicina y oxitetraciclina incrementaron el tiempo requerido en el proceso de elaboración. Respecto a las características del queso evaluadas a diferentes tiempos de maduración (0, 30 y 60 días), las pocas diferencias encontradas se refirieron a la concentración de ácidos grasos libres, el color y las propiedades de textura, pero en su mayoría no fueron detectadas en la evaluación sensorial. Sin embargo, cantidades variables de antibióticos, se transfirieron de la leche al queso (entre 7,4 y 68%). Las quinolonas y oxitetraciclina presentaron las más elevadas tasas de retención, así como persistencia a lo largo de la maduración, con altas concentraciones de quinolonas (enrofloxacina: 148±12 µg/kg; ciprofloxacina: 253±24 µg/kg) y de oxitetraciclina (20±5,7 µg/kg) después de los 60 días de curado.
En el estudio de quesos frescos, se evaluó la presencia de residuos de medicamentos en la leche pasteurizada y en los quesos frescos a partir de leche de cabra con antibióticos (amoxicilina, bencilpenicilina, cloxacilina, neomicina, eritromicina, ciprofloxacina, enrofloxacina y oxitetraciclina) a niveles de seguridad (LMR). Los resultados mostraron que altas cantidades de antibióticos, entre el 71 y el 100% de la concentración inicial en la leche cruda, permanecieron en la leche pasteurizada y que fueron transferidas al queso en gran medida, con porcentajes de retención que oscilaron entre 37,5 y 75%. Con respecto a los márgenes de seguridad de estos productos, se calcularon teniendo en cuenta diferentes grupos de edades (niños, adolescentes y adultos), y los efectos negativos de estos antibióticos sobre la salud. Los resultados indicaron que el mínimo margen de seguridad en la leche pasteurizada lo presentaron la ciprofloxacina, enrofloxacina, y eritromicina para el grupo de niños. En relación al queso fresco, se obtuvo un elevado margen de seguridad para todos los antibióticos y grupos de edad considerados, lo que sugiere que este producto probablemente no tenga efectos negativos en la salud del consumidor.
Es importante enfatizar que concentraciones relativamente altas de antibióticos podrían permanecer en la leche de cabra pasteurizada y productos relacionados, como los quesos frescos y de corta maduración. La presencia de estos antibióticos podría contribuir al desarrollo y propagación de la resistencia a los antimicrobianos que actualmente constituye un grave problema a nivel mundial. Los resultados de este trabajo podrían servir a las autoridades de salud pública para evaluar si los sistemas actuales de control de antibióticos en la leche y los productos lácteos son adecuados o deberían ser revisados. / [CA] Els residus d'antibiòtics en la llet animal constitueixen un aspecte de gran importància per a la salut pública, i poden tindre un efecte negatiu en la indústria làctia. Per a protegir al consumidor s'han establit els Límits Màxims de Residus (LMR) per a diferents medicaments veterinaris en la llet crua. No obstant això, la transferència d'estes substàncies de la llet al formatge ha sigut poc estudiada i, per tant, es desconeix el impacte de la presència de antibiòtics sobre el procés d'elaboració i la seguretat del formatge.
L'objectiu de la tesi ha sigut avaluar la transferència dels antibiòtics més empleats en el bestiar caprí lleter, des de la llet a formatges curats i frescos, així com l'efecte sobre el procés de fabricació i la qualitat dels formatges durant la maduració.
Per a aconseguir l'objectiu s'han realitzat elaboracions de formatges curats (60 dies) a partir de llet en presència de diversos antibiòtics (amoxicilina, bencilpenicilina, cloxacilina, eritromicina, ciprofloxacina, enrofloxacina i oxitetraciclina) a nivells admissibles (LMR) i fabricacions de llet lliure d'antibiòtic (control) com a referència. Els resultats obtinguts suggerixen que la major part dels antibiòtics en la llet no van afectar el procés de fabricació del formatge. Només l'eritromicina i l'oxitetraciclina van incrementar el temps requerit en el procés d'elaboració del formatge. Respecte a les característiques del formatge avaluades a diferents temps de maduració (0, 30 i 60 dies), les poques diferències trobades es van referir a la concentració d'àcids greixos lliures, el color i les propietats de textura, però majoritàriament no van ser detectades en l'avaluació sensorial. No obstant això, quantitats variables d'antibiòtics, es van transferir de la llet al formatge (entre 7,4 i 68%). Les quinolones i l'oxitetraciclina van presentar les més elevades taxes de retenció, així com persistència al llarg de la maduració, amb altes concentracions de quinolones (enrofloxacina: 148±12 µg/kg; ciprofloxacina: 253±24 µg/kg) i d'oxitetraciclina (20±5,7 µg / kg) després dels 60 dies de curació.
En l'estudi de formatges frescos, es va avaluar la presència de residus de medicaments en la llet pasteuritzada i en els formatges frescos a partir de llet de cabra amb antibiòtics (amoxicilina, bencilpenicilina, cloxacilina, neomicina, eritromicina, ciprofloxacina, enrofloxacina i oxitetraciclina) a nivells de seguretat (LMR). Els resultats van mostrar que altes quantitats d'antibiòtics, entre el 71 i el 100% de la concentració inicial en la llet crua, van romandre en la llet pasteuritzada i que van ser transferides al formatge en gran manera, amb percentatges de retenció que van oscil·lar entre 37,5 i 75%. Respecte als marges de seguretat d'estos productes, es van calcular tenint en compte diferent grups d'edats (xiquets, adolescents i adults), i els efectes negatius d'estos antibiòtics sobre la salut. Els resultats van indicar que el mínim marge en la llet pasteuritzada ho van presentar la ciprofloxacina, la enrofloxacina, i l'eritromicina per al grup de xiquets. En relació al formatge fresc, es va obtindre un elevat marge de seguretat per a tots els antibiòtics i grups d'edat considerats, la qual cosa suggereix que este producte probablement no tinga efectes negatius en la salut del consumidor.
És important emfatitzar que concentracions relativament altes d'antibiòtics podrien romandre en la llet de cabra pasteuritzada i productes relacionats, com els formatges frescos i de curta maduració. La presència d'estos antibiòtics podria contribuir al desenrotllament i propagació de la resistència als antimicrobians que actualment constitueix un greu problema a nivell mundial. Els resultats d'este treball podrien servir les autoritats de salut pública per a avaluar si els sistemes actuals de control d'antibiòtics en la llet i els productes lactis són adequats o haurien de ser revisats. / [EN] Antibiotic residues in milk are a great concern for public health, and they have negative implications for the dairy industry. To guarantee the safety of milk and derivates, Maximum Residues Limits (MRL) for different veterinary drugs in raw milk have been established. However, the transfer of these substances from milk to cheese, has been poorly studied and, therefore, the impact of the use of raw milk containing antibiotics on the cheese-making and the cheese safety is thus far unknown.
The aim of this thesis was to evaluate the transfer of the most widely used antibiotics used in dairy goats, from milk to matured and fresh cheese, as well as their effect on the cheese-making process and the quality characteristics of the cheeses during ripening.
To this end, antibiotic-free milk was spiked individually with seven veterinary drugs (amoxicillin, benzylpenicillin, cloxacillin, erythromycin, ciprofloxacin, enrofloxacin and oxytetracycline) and used to make mature Tronchón cheeses, which were analyzed at different ripening times (0, 30, and 60 days) to determine antibiotic residues, pH, chemical composition, proteolytic and lipolytic activities, color, and textural properties. The cheese-making process was unaffected by the presence of most antibiotics in milk. Only erythromycin and oxytetracycline significantly increased the time required for cheese production. Regarding cheese characteristics, the few differences found were related to the free fatty acid concentration, color and textural properties, which remained mostly undetected by the sensory analysis panelists. However, variable amounts of antibiotics, ranging from 7.4 to 68 %, were transferred from milk spiked with antibiotics, to cheese. Oxytetracycline and quinolones presented the highest retention rates as well as persistence along maturation, with high concentrations of quinolones (enrofloxacin: 148±12 µg/kg, ciprofloxacin: 253±24 µg/kg) and oxytetracycline residues (20±5.7 µg/kg) in cheeses after 60 days of ripening.
In the study of fresh cheeses was evaluated the presence of drug residues in pasteurized fluid milk and fresh cheeses obtained from goat milk containing antibiotics (amoxicillin, benzylpenicillin, cloxacillin, neomycin, erythromycin, ciprofloxacin, enrofloxacin and oxytetracycline) at safety levels (MRLs). The safety margin of these dairy products for consumers was also evaluated. Results showed that high amounts of antibiotics, between 71-100% of the initial concentration in raw milk, remained in pasteurized goat milk and were transferred to cheese to a high extent, with retention percentages ranging from 37.5 to 75%. Regarding the safety margin of goat milk products, calculated taking into account different age groups (children, teenagers and adults), and the published negative effects of such antibiotics on consumer health, results indicate that the minimum safety margin of pasteurized milk was obtained for ciprofloxacin, enrofloxacin and erythromycin in the group of children. Regarding fresh cheese, an elevated safety margin was obtained for all antibiotics and age groups considered.
It is important to emphasize that relatively high concentrations of antibiotics could remain in pasteurized fluid goat milk and related products such as fresh cheese and cheeses of a short ripening period. The presence of these antibiotics in dairy products might contribute to the development and spread of antimicrobial resistance, which is considered an important public health concern worldwide. The result of this research could serve the public health authorities to assess if current control systems of antibiotics in milk and dairy products are adequate or have to be revised. / Por último, quiero dar las gracias a la educación pública que permite que la
economía no sea una barrera para la formación y al “Programa de ayudas a la
investigación” (FPI-2014) de la Universitat Politècnica de Valencia, que me concedió
la oportunidad de realizar está investigación durante los 4 años de trabajo. / Quintanilla Vázquez, PG. (2019). Effect of antibiotics in goat milk on the manufacture and characteristics of cheese [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/125701 / TESIS / Compendio
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Nutrição de precisão para frangos de corte / Precision nutricion for broilerUtimi, Natália Barros Petroli 12 August 2016 (has links)
Três experimentos foram realizados no Departamento de Zootecnia da Universidade de São Paulo (USP), na faculdade de Zootecnia e Engenharia de Alimentos (FZEA), em Pirassununga/SP, com o objetivo de avaliar o uso do conceito de nutrição de precisão para frangos de corte e sua viabilidade econômica. No primeiro experimento foram realizadas coletas mensais durante um ano para levantamento de dados sobre a qualidade destes ingredientes. Ao final foi realizado um experimento em esquema fatorial 2 x 4 (duas empresas e quatro estações do ano) totalizando 8 tratamentos com três repetições cada. Foram avaliados Proteína Bruta (PB), matéria seca (MS), umidade (U), perfil de aminoácidos, e fósforo através da tecnologia NIR além da classificação de acordo com a metodologia descrita na Portaria 845 do MAPA. Os resultados demonstram a importância na seleção de fornecedores e que as rações devem ser formuladas de acordo com as diferenças qualitativas que ocorrem entre os meses do ano e entre fornecedores e que em algumas épocas o milho encontra-se abaixo do padrão de qualidade. No segundo foram utilizados 960 pintos de um dia de idade, machos, Cobb-500, distribuídos em um delineamento inteiramente ao acaso em esquema fatorial 2 x 4, 2x4: 2 fontes de milho e farelo de soja (empresa e universidade) e 4 matrizes nutricionais (média anual dos dados colhidos mensalmente na empresa; matriz nutricional praticados pela empresa; matriz nutricional determinadas por Rostagno et al (2011) e matriz nutricional determinada na fábrica de ração no momento de produção das dietas, através da utilização do NIRS), totalizando 8 tratamentos com 10 repetições de 12 animais cada. Foram avaliados o desempenho, rendimento de carcaça e de cortes comerciais e a viabilidade econômica. A origem dos ingredientes influenciou o desempenho das aves e a viabilidade econômica induziu uma diferença no rendimento de carcaça até os 33 dias de idade. O desempenho até 33 dias foi superior nos animais que receberam a matriz nutricional utilizada pela empresa ou com análise prévia dos ingredientes. No terceiro foram utilizados 720 frangos de corte, machos, Cobb 500 distribuídos em um delineamento inteiramente casualizado com esquema fatorial 2x4: 2 fontes de milho e farelo de soja (empresa e universidade) e 4 matrizes nutricionais (média anual dos dados colhidos mensalmente na empresa; matriz nutricional praticados pela empresa; matriz nutricional determinadas por Rostagno et al (2011) e matriz nutricional determinada na fábrica de ração no momento de produção das dietas, através da utilização do NIRS), totalizando 8 tratamentos com 9 repetições de 10 animais cada. Foram avaliados Os resultados para coeficiente de digestibilidade da proteína bruta (CDPB), matéria mineral (CDMM), extrato etéreo (CDEE), cálcio (CDCa) e fósforo (CDP). As variáveis CDPB, CDMM e CDP não apresentaram diferença estatística entre as aves alimentadas com os ingredientes de ambos fornecedores e dentre as diferentes matrizes nutricionais. A origem dos ingredientes influenciou o CDEE e a matriz nutricional da empresa mostrou melhor CDCa. / Three experiments were conducted in the Animal Science Department of the University of São Paulo (USP), the College of Animal Science and Food Engineering (FZEA) in Pirassununga / SP, in order to evaluate the use of precision nutrition concept for chickens cutting and its economic viability. In the first experiment we have been collected monthly for one year for data collection on the quality of ingredients. At the end of an experiment was conducted in factorial 2 x 4 (two companies and four seasons), totaling eight treatments with three repetitions each. They were evaluated crude protein crude protein (CP), ether extract (EE), amino acid profile, calcium and phosphorus by NIR technology beyond classification according to the methodology described in Ordinance 845 MAP. The results demonstrate the importance in the selection of suppliers and rations should be formulated according to the qualitative differences that occur between the months of the year and between suppliers and at times some corn is below the standard of quality. In the second we used 960 chickens a day old, male, Cobb-500, distributed in a completely randomized design in a factorial 2 x 4, 2x4: 2 sources of corn and soybean meal (company and university) and 4 matrices nutritional (annual average of data collected monthly in the company; nutritional matrix practiced by the company; nutritional matrix determined by Rostagno et al (2011) and certain nutritional matrix in the feed factory at the time of production of diets by using NIRS), totaling 8 treatments with 10 repetitions of 12 animals each. In the third we evaluated the performance, carcass yield and commercial cuts and economic viability. The origin of ingredients influenced the performance of birds and the economic viability induced a difference in carcass yield up to 33 days old. The performance up to 33 days was higher in animals receiving nutritional matrix used by the company or with prior analysis of the ingredients. We used 720 broilers, males, Cobb 500 distributed in a completely randomized design with a 2x4 factorial design: 2 sources of corn and soybean meal (company and university) and 4 nutritional matrixes (annual average of data collected monthly in the company, Matrix nutritional practiced by the company; nutritional matrix determined by Rostagno et al (2011) and certain nutritional matrix in the feed factory at the time of production of diets by using NIRS), totalizing 8 treatments with nine replications of 10 animals each. We evaluated the results for crude protein digestibility coefficient (CPDC), mineral matter (CDMM), ethereal extract (EEDC), calcium (CDCA) and phosphorus (CDP). The CDCP variables, CDMM and CDP showed no statistical difference between the birds fed the ingredients of both suppliers and among the different nutritional matrixes. The origin of ingredients influenced the EEDC and nutritional matrix company showed better CDCA.
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Dealing with uncertaintyClausen Mork, Jonas January 2012 (has links)
Uncertainty is, it seems, more or less constantly present in our lives. Even so, grasping the concept philosophically is far from trivial. In this doctoral thesis, uncertainty and its conceptual companion information are studied. Axiomatic analyses are provided and numerical measures suggested. In addition to these basic conceptual analyses, the widespread practice of so-called safety factor use in societal regulation is analyzed along with the interplay between science and policy in European regulation of chemicals and construction. / QC 20120202
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Nutrição de precisão para frangos de corte / Precision nutricion for broilerNatália Barros Petroli Utimi 12 August 2016 (has links)
Três experimentos foram realizados no Departamento de Zootecnia da Universidade de São Paulo (USP), na faculdade de Zootecnia e Engenharia de Alimentos (FZEA), em Pirassununga/SP, com o objetivo de avaliar o uso do conceito de nutrição de precisão para frangos de corte e sua viabilidade econômica. No primeiro experimento foram realizadas coletas mensais durante um ano para levantamento de dados sobre a qualidade destes ingredientes. Ao final foi realizado um experimento em esquema fatorial 2 x 4 (duas empresas e quatro estações do ano) totalizando 8 tratamentos com três repetições cada. Foram avaliados Proteína Bruta (PB), matéria seca (MS), umidade (U), perfil de aminoácidos, e fósforo através da tecnologia NIR além da classificação de acordo com a metodologia descrita na Portaria 845 do MAPA. Os resultados demonstram a importância na seleção de fornecedores e que as rações devem ser formuladas de acordo com as diferenças qualitativas que ocorrem entre os meses do ano e entre fornecedores e que em algumas épocas o milho encontra-se abaixo do padrão de qualidade. No segundo foram utilizados 960 pintos de um dia de idade, machos, Cobb-500, distribuídos em um delineamento inteiramente ao acaso em esquema fatorial 2 x 4, 2x4: 2 fontes de milho e farelo de soja (empresa e universidade) e 4 matrizes nutricionais (média anual dos dados colhidos mensalmente na empresa; matriz nutricional praticados pela empresa; matriz nutricional determinadas por Rostagno et al (2011) e matriz nutricional determinada na fábrica de ração no momento de produção das dietas, através da utilização do NIRS), totalizando 8 tratamentos com 10 repetições de 12 animais cada. Foram avaliados o desempenho, rendimento de carcaça e de cortes comerciais e a viabilidade econômica. A origem dos ingredientes influenciou o desempenho das aves e a viabilidade econômica induziu uma diferença no rendimento de carcaça até os 33 dias de idade. O desempenho até 33 dias foi superior nos animais que receberam a matriz nutricional utilizada pela empresa ou com análise prévia dos ingredientes. No terceiro foram utilizados 720 frangos de corte, machos, Cobb 500 distribuídos em um delineamento inteiramente casualizado com esquema fatorial 2x4: 2 fontes de milho e farelo de soja (empresa e universidade) e 4 matrizes nutricionais (média anual dos dados colhidos mensalmente na empresa; matriz nutricional praticados pela empresa; matriz nutricional determinadas por Rostagno et al (2011) e matriz nutricional determinada na fábrica de ração no momento de produção das dietas, através da utilização do NIRS), totalizando 8 tratamentos com 9 repetições de 10 animais cada. Foram avaliados Os resultados para coeficiente de digestibilidade da proteína bruta (CDPB), matéria mineral (CDMM), extrato etéreo (CDEE), cálcio (CDCa) e fósforo (CDP). As variáveis CDPB, CDMM e CDP não apresentaram diferença estatística entre as aves alimentadas com os ingredientes de ambos fornecedores e dentre as diferentes matrizes nutricionais. A origem dos ingredientes influenciou o CDEE e a matriz nutricional da empresa mostrou melhor CDCa. / Three experiments were conducted in the Animal Science Department of the University of São Paulo (USP), the College of Animal Science and Food Engineering (FZEA) in Pirassununga / SP, in order to evaluate the use of precision nutrition concept for chickens cutting and its economic viability. In the first experiment we have been collected monthly for one year for data collection on the quality of ingredients. At the end of an experiment was conducted in factorial 2 x 4 (two companies and four seasons), totaling eight treatments with three repetitions each. They were evaluated crude protein crude protein (CP), ether extract (EE), amino acid profile, calcium and phosphorus by NIR technology beyond classification according to the methodology described in Ordinance 845 MAP. The results demonstrate the importance in the selection of suppliers and rations should be formulated according to the qualitative differences that occur between the months of the year and between suppliers and at times some corn is below the standard of quality. In the second we used 960 chickens a day old, male, Cobb-500, distributed in a completely randomized design in a factorial 2 x 4, 2x4: 2 sources of corn and soybean meal (company and university) and 4 matrices nutritional (annual average of data collected monthly in the company; nutritional matrix practiced by the company; nutritional matrix determined by Rostagno et al (2011) and certain nutritional matrix in the feed factory at the time of production of diets by using NIRS), totaling 8 treatments with 10 repetitions of 12 animals each. In the third we evaluated the performance, carcass yield and commercial cuts and economic viability. The origin of ingredients influenced the performance of birds and the economic viability induced a difference in carcass yield up to 33 days old. The performance up to 33 days was higher in animals receiving nutritional matrix used by the company or with prior analysis of the ingredients. We used 720 broilers, males, Cobb 500 distributed in a completely randomized design with a 2x4 factorial design: 2 sources of corn and soybean meal (company and university) and 4 nutritional matrixes (annual average of data collected monthly in the company, Matrix nutritional practiced by the company; nutritional matrix determined by Rostagno et al (2011) and certain nutritional matrix in the feed factory at the time of production of diets by using NIRS), totalizing 8 treatments with nine replications of 10 animals each. We evaluated the results for crude protein digestibility coefficient (CPDC), mineral matter (CDMM), ethereal extract (EEDC), calcium (CDCA) and phosphorus (CDP). The CDCP variables, CDMM and CDP showed no statistical difference between the birds fed the ingredients of both suppliers and among the different nutritional matrixes. The origin of ingredients influenced the EEDC and nutritional matrix company showed better CDCA.
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A probabilistic and multi-objective conceptual design methodology for the evaluation of thermal management systems on air-breathing hypersonic vehiclesOrdaz, Irian 18 November 2008 (has links)
This thesis addresses the challenges associated with thermal management systems (TMS) evaluation and selection in the conceptual design of hypersonic, air-breathing vehicles with sustained cruise. The proposed methodology identifies analysis tools and techniques which allow the proper investigation of the design space for various thermal management technologies.
The design space exploration environment and alternative multi-objective decision making technique defined as Pareto-based Joint Probability Decision Making (PJPDM) is based on the approximation of 3-D Pareto frontiers and probabilistic technology effectiveness maps. These are generated through the evaluation of a Pareto Fitness function and Monte Carlo analysis. In contrast to Joint Probability Decision Making (JPDM), the proposed PJPDM technique does not require preemptive knowledge of weighting factors for competing objectives or goal constraints which can introduce bias into the final solution. Preemptive bias in a complex problem can degrade the overall capabilities of the final design. The implementation of PJPDM in this thesis eliminates the need for the numerical optimizer which is required with JPDM in order to improve upon a solution.
In addition, a physics-based formulation is presented for the quantification of TMS safety effectiveness corresponding to debris impact/damage and how it can be applied towards risk mitigation. Lastly, a formulation loosely based on non-preemptive Goal Programming with equal weighted deviations is provided for the resolution of the inverse design space. This key step helps link vehicle capabilities to TMS technology subsystems in a top-down design approach. The methodology provides the designer more knowledge up front to help make proper engineering decisions and assumptions in the conceptual design phase regarding which technologies show greatest promise, and how to guide future technology research.
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Robust Explicit Construction of 3D Configuration Spaces Using Controlled Linear PerturbationTrac, Steven Cy 19 December 2008 (has links)
We present robust explicit construction of 3D configuration spaces using controlled linear perturbation. The input is two planar parts: a fixed set and a moving set, where each set is bounded by circle segments. The configuration space is the three-dimensional space of Euclidean transformation (translations plus rotations) of the moving set relative to the fixed set. The goal of constructing the 3D configuration space is to determine the boundary representation of the free space where the intersection of the moving set and fixed set is empty. To construct the configuration space, we use the controlled linear perturbation algorithm. The controlled linear perturbation algorithm assigns function signs that are correct for a nearly minimal input perturbation. The output of the algorithm is a consistent set of function signs. This approach is algorithm-independent, and the overhead over traditional floating point methods is reasonable. If the fixed and moving sets are computer representations of physical objects, then computing the configuration space greatly aids in many computational geometry problems. The main focus of computing the configuration space is for the path planning problem. We must find if a path exists from the start to the goal, where the fixed set is the obstacle, and the moving set is the object trying to reach the goal.
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Etudes des contre-réactions dans un réacteur à neutrons rapides à caloporteur sodium : impact de la conception et de la neutronique sur les incertitudes / Study of Reactivity Feedbacks in a Sodium-Cooled Fast Reactor : New methodology based on perturbation theory for evaluating neutronic uncertaintiesBouret, Cyrille 13 November 2014 (has links)
Les réacteurs de IVème génération à neutrons rapides offrent la possibilité de valoriser le plutonium produit par le parc actuel des réacteurs à eau légère et de transmuter une part déterminante des déchets ultimes. Actuellement, de nouveaux projets de réacteurs à neutrons rapides sont étudiés dans le monde et doivent satisfaire de nouvelles exigences en termes d’économie des ressources, de réduction des déchets, de compétitivité, de sûreté et de fiabilité. Ainsi, ces nouveaux projets intègrent des innovations qui permettent d’améliorer la sûreté du réacteur (comportement naturel du coeur) en cas d’accident. Dans le cas du prototype ASTRID étudié en France au CEA, ces innovations portent sur le design géométrique du coeur et notamment l’intégration d’une plaque fertile au centre et d’un plenum de sodium en partie supérieure afin d’augmenter les fuites de neutrons en cas de vidange en sodium. Ces designs hétérogènes sont caractérisés par des vidanges en sodium proches de zéro résultant de fortes compensations entre les différentes zones du coeur. L’évaluation des grandeurs neutroniques d’intérêt nécessitent alors des outils de calculs robustes dans le but de traiter rigoureusement le transport des neutrons, et notamment au niveau des interfaces entre milieux. Le premier travail de thèse a donc consisté à améliorer la méthodologie existante permettant d’évaluer au mieux les grandeurs neutroniques d’intérêt. Ces améliorations ont consisté à développer une méthode d’analyse spécifique basée sur la théorie des perturbations et l’utilisation d’un solveur de flux moderne en transport Sn. Ce travail a permis d’une part, de réduire les biais de calcul sur les grandeurs neutroniques d’intérêt par rapport à des méthodes de référence (Monte Carlo) et, d’autre part, d’obtenir des distributions spatiales des effets neutroniques plus précises, et notamment des coefficients locaux de contre-réactions utilisés pour les analyses de transitoires non-protégés caractérisant le niveau « naturel » de « sûreté » du coeur. Par ailleurs, les incertitudes sur ces paramètres neutroniques ont un impact important sur les performances et la sûreté du coeur en termes de marges à prendre lors de la phase de conception. Il est donc important de les maîtriser et de les réduire afin de conserver les gains envisagés par le concept CFV. Ces incertitudes ont pour origines : les données nucléaires (sections efficaces macroscopiques pour une composition du coeur donnée), les données technologiques (données de fabrication et notamment la géométrie, les concentrations atomiques des constituants du coeur et les lois de dilatations thermiques),l’évolution du bilan matière dans le coeur sous irradiation, la thermique du combustible, les biais provenant des solveurs, des schémas de calculs (et de la modélisation) et des méthodes utilisées. Par ailleurs, les incertitudes sur la composition du coeur irradié et la thermique du combustible sont elles-mêmes fortement affectées par celles sur les données nucléaires. La propagation des incertitudes issues des données nucléaires sur les grandeurs neutroniques est donc complexe car faisant intervenir plusieurs sources de corrélation. Cette complexité est en outre accrue si l’on souhaite évaluer la corrélation spatiale des grandeurs neutroniques et des incertitudes associées. Le deuxième objectif de la thèse a donc consisté à mettre en place une méthodologie permettant de propager les incertitudes issues des données nucléaires sur les grandeurs neutroniques. Cette méthodologie se base sur l’évaluation de coefficients locaux de sensibilités permettant de déterminer les corrélations entre les différents paramètres neutroniques. (...) / Fast reactors (FR) can give value to the plutonium produced by the existing light water reactors and allow the transmutation of a significant part of the final nuclear waste. These features offer industrial prospects for this technology and new projects are currently studied in the world such as ASTRID prototype in France. Future FRs will have also to satisfy new requirements in terms of competitiveness, safety and reliability. In this context, the new core concept envisaged for ASTRID incorporate innovative features that improve the safety of the reactor in case of accident. The proposed design achieves a sodium voiding effect close to zero: it includes a fertile plate in the middle of the core and a sodium plenum in the upper part in order to increase the neutron leakage in case of sodium voiding. This heterogeneous design represents a challenge for the calculation tools and methods used so far to evaluate the neutronic parameters in traditional homogeneous cores. These methods have been improved over the thesis to rigorously treat the neutron streaming, especially at the mediums interfaces. These enhancements have consisted in the development of a specific analysis methodology based on perturbation theory and using a modern three dimensional Sn transport solver. This work has allowed on the one hand, to reduce the bias on static neutronic parameters in comparison with Monte Carlo methods, and, on the other hand, to obtain more accurate spatial distributions of neutronic effects including the reactivity feedback coefficients used for transient analysis. The analysis of the core behavior during transients has also allowed estimating the impact of reactivity feedback coefficients assessment improvements. In conjunction with this work, innovative methods based on the evaluation of local sensitivities coefficients have been proposed to assess the uncertainties associated to local reactivity effects. These uncertainties include the correlations between the different local parameters. The propagation during transients with these methods has allowed an estimation of temperature distributions achieved in the core and also to determine the available safety margins before sodium boiling.
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