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Toward an Uncertain Modeling of Hypersonic Aerodynamic ForcesJanuary 2017 (has links)
abstract: The focus of this investigation is on the development of a surrogate model of hypersonic aerodynamic forces on structures to reduce the computational effort involved in the determination of the structural response. The application is more precisely focused on uncertain structures. Then, following an uncertainty management strategy, the surrogate may exhibit an error with respect to Computational Fluid Dynamics (CFD) reference data as long as that error does not significantly affect the uncertainty band of the structural response. Moreover, this error will be treated as an epistemic uncertainty introduced in the model thereby generating an uncertain surrogate. Given this second step, the aerodynamic surrogate is limited to those exhibiting simple analytic forms with parameters that can be identified from CFD data.
The first phase of the investigation focuses on the selection of an appropriate form for the surrogate for the 1-dimensional flow over a flat clamped-clamped. Following piston theory, the model search started with purely local models, linear and nonlinear of the local slope. A second set of models was considered that involve also the local displacement, curvature, and integral of displacement and an improvement was observed that can be attributed to a global effect of the pressure distribution. Various ways to involve such a global effect were next investigated eventually leading to a two-level composite model based on the sum of a local component represented as a cubic polynomial of the downwash and a global component represented by an auto-regressive moving average (ARMA) model driven nonlinearly by the local downwash. This composite model is applicable to both steady pressure distributions with the downwash equal to the slope and to unsteady cases with the downwash as partial derivative with time in addition to steady.
The second part of the investigation focused on the introduction of the epistemic uncertainty in the aerodynamic surrogate and it was recognized that it could be achieved by randomizing the coefficients of the local and/or the auto-regressive components of the model. In fact, the combination of the two effects provided an applicable strategy. / Dissertation/Thesis / Masters Thesis Mechanical Engineering 2017
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Evaluation of Testing Methods for Suction-Volume Change of Natural Clay SoilsJanuary 2017 (has links)
abstract: Design and mitigation of infrastructure on expansive soils requires an understanding of unsaturated soil mechanics and consideration of two stress variables (net normal stress and matric suction). Although numerous breakthroughs have allowed geotechnical engineers to study expansive soil response to varying suction-based stress scenarios (i.e. partial wetting), such studies are not practical on typical projects due to the difficulties and duration needed for equilibration associated with the necessary laboratory testing. The current practice encompasses saturated “conventional” soil mechanics testing, with the implementation of numerous empirical correlations and approximations to obtain an estimate of true field response. However, it has been observed that full wetting rarely occurs in the field, leading to an over-conservatism within a given design when partial wetting conditions are ignored. Many researchers have sought to improve ways of estimation of soil heave/shrinkage through intense studies of the suction-based response of reconstituted clay soils. However, the natural behavior of an undisturbed clay soil sample tends to differ significantly from a remolded sample of the same material.
In this study, laboratory techniques for the determination of soil suction were evaluated, a methodology for determination of the in-situ matric suction of a soil specimen was explored, and the mechanical response to changes in matric suction of natural clay specimens were measured. Suction-controlled laboratory oedometer devices were used to impose partial wetting conditions, similar to those experienced in a natural setting. The undisturbed natural soils tested in the study were obtained from Denver, CO and San Antonio, TX.
Key differences between the soil water characteristic curves of the undisturbed specimen test compared to the conventional reconstituted specimen test are highlighted. The Perko et al. (2000) and the PTI (2008) methods for estimating the relationship between volume and changes in matric suction (i.e. suction compression index) were evaluated by comparison to the directly measured values. Lastly, the directly measured partial wetting swell strain was compared to the fully saturated, one-dimensional, oedometer test (ASTM D4546) and the Surrogate Path Method (Singhal, 2010) to evaluate the estimation of partial wetting heave. / Dissertation/Thesis / Masters Thesis Engineering 2017
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Congruência entre grupos biológicos em uma planície de inundação neotropicalVieira, Marisa Cristina Lários 18 December 2014 (has links)
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Previous issue date: 2014-12-18 / CNPq / A análise de congruência em comunidades é utilizada para verificar se grupos biológicos
apresentam padrões de distribuição semelhantes ao longo de um gradiente ambiental.
Quando ocorre congruência entre os grupos, é possível a seleção de um grupo biológico
para monitorar outros, denominado grupo substituto. Nesse contexto, avaliei a congruência
entre sete grupos biológicos, para a seleção de um possível grupo substituto. Avaliei
também a influência dos fatores espacias e ambientais no padrão de congruência entre os
grupos. Os dados foram coletados em um sítio de pesquisa de longa duração no Pantanal
brasileiro nos anos de 2006 e 2007 no período da seca. Os grupos biológicos utilizados
foram: plantas herbáceas, plantas lenhosas, anuros, aves, morcegos, aranhas e pequenos
mamíferos. A congruência entre os grupos foi avaliada utilizando o teste de Mantel, e
aquele que apresentou a maior média de coeficiente de correlação (r) foi considerado o
melhor grupo substituto. Através da partição de variância, avaliei a influência dos fatores
ambientais e espaciais na estruturação da comunidade e sua influência na congruência.
Como variáveis ambientais, utilizei dados da estrutura física do solo (silte e argila),
inundação (duração e amplitude), altitude e estrato da vegetação, e como preditores
espaciais usei mapas de autovetores de Moran. O grupo de plantas lenhosas apresentou a
maior média de coeficiente de correlação, seguido por herbáceas, aranhas, anuros, aves e
pequenos mamíferos. O maior valor de congruência foi encontrado entre herbáceas e
plantas lenhosas, e o menor, entre morcegos e herbáceas. Os preditores ambientais que
mais influenciaram na estrutura da comunidade vegetal foram os ligados à inundação, e
grupos da fauna apresentaram maior influência da vegetação. Deste modo, concluo que o
grupo plantas lenhosas é capaz de representar a diversidade dos demais grupos,
simplificando o monitoramento ambiental. / The congruence analysis in communities is used for check if biological groups show the
same patterns of distribution along an environmental gradient. When occurs congruence
between groups is possible the selection of one biological group for to monitor others, called
surrogate. In this context, I evaluated the congruence between seven biological groups for
selection of one possible group. I also evaluated the influence of spatial and environment
factors in pattern of congruence between of these groups. Datasets was collected in a longterm
research site in the Brazilian Pantanal in 2006 and 2007 during dry season. The
biological groups used were: herbaceous plants, woody plants, frogs, birds, bats, spiders
and small mammals. The congruence between groups was evaluated using Mantel test, and
one who showed the bigger average of correlation coefficient (r) was considered the best
surrogate. Through of partitioning of variation, evaluated the influence of spatial and
environmental factors in community structure and your influence in congruence. How
environmental variables, I used the physical structure data of soil (silt and clay), flood
(duration and amplitude), altitude and stratum of vegetation, and as spatial predictors used
maps eigenvectors Moran. The woody plants group showed the better average of correlation
coefficient, followed for herbaceous, spiders, frogs, birds and small mammals. The higher
value of congruence was found between herbaceous and woody plants, and the lower,
between bats and herbaceous. The environmental predictors that has more influence in the
community structure are linked the flood, and groups of fauna showed higher influence of
vegetation. This way, I conclude that woody plants group is able of represent the biodiversity
of others groups, simplifying the environmental monitoring.
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Quem sai aos seus não degenera? a (des)ordem da gestação de substituiçãoViana, Kelly Ribeiro de Freitas January 2017 (has links)
Trata-se de uma pesquisa qualitativa com base nos Estudos Culturais, em sua vertente pós-estruturalista. O objetivo foi analisar publicações de jornais, livros, sites e revistas que veicularam reportagens sobre Gestação de Substituição, para conhecer os discursos que circularam na mídia sobre a temática. Gestação de Substituição está dentre as técnicas que compõem o conjunto da reprodução assistida que combina a fertilização in vitro com a implantação do embrião (com o material genético de outrem) no útero da mãe substituta. Para tanto, foram analisadas reportagens cujo tema central eram histórias de sujeitos que participaram do processo de Gestação de Substituição. A análise desse corpus foi fundamentada nas ferramentas propostas por Michel Foucault, especialmente de discurso, enunciado e arquivo. Assumindo a mídia como artefato cultural que nos subjetiva e instiga determinados modos de vida, pretendi realizar uma das possíveis leituras dessas reportagens. Da análise emergiram três marcadores: nos Contos de fadas: uma estratégia discursiva midiática, observei que as histórias são contadas respeitando determinados enredos das tradicionais histórias infantis, posicionando os sujeitos participantes da Gestação de Substituição como heróis. Em Mães substitutas: sujeitos forjados pelos discursos midiático, biomédico e moral, as análises apontaram que os pais biológicos admiram tais mulheres por gestar o filho de outrem. No marcador, A família feliz: uma instituição social reorganizada discursivamente, destacou que as mães biológicas podem vivenciar a gestação, uma gravidez possível e o amor materno. Portanto, minha proposta foi (re)pensar e fazer outras e novas perguntas sobre o tema e suscitar reflexões que possam contribuir para a assistência em saúde dos sujeitos envolvidos no processo de Gestação de Substituição. E, neste sentido, procurar fornecer subsídios para que a Enfermagem (re)pense suas práticas para atender as demandas dessas novas famílias. / This is a qualitative research based on Cultural Studies, in its poststructuralist dimension. The objective was to analyze publications of newspapers, books, websites and magazines that have provided reports on Surrogacy to know the speeches that have circulated in the media about the theme. Surrogacy is among the techniques that make up assisted reproduction that combines in vitro fertilization with the implantation of the embryo (with the genetic material of another) in the uterus of the surrogate mother. For that we have analyzed reports whose central theme were stories of subjects who participated in the process of Surrogacy. The analysis of this corpus was based on the tools proposed by Michel Foucault, especially discourse, statement and archive. Assuming the media as a cultural artifact that subjective and instigates certain ways of life, I intended to carry out one of the possible readings of these reports. From the analysis emerged three markers: In Fairy Tales: a media discursive strategy I observed that the stories are told respecting certain scenarios of the traditional children's stories, positioning the subjects participating in the Surrogacy as heroes. In Surrogate mothers: subjects forged by the media, biomedic and moral discourses, the analyses pointed out those biological parents admire such women for gestating the child of another. In the bookmark, The Happy Family: a social institution discursively reorganized, emphasized that biological mothers can experience gestation, a possible pregnancy and maternal love. Therefore, my proposal was to (re)think and make other and new questions on this topic and to raise reflections that could contribute to the health care of the subjects involved in the Surrogacy process. And, in this sense, seek to provide subsidies for Nursing to (re)think their practices to meet the demands of these new families.
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Aplicação de um modelo substituto para otimização estrutural topológica com restrição de tensão e estimativa de erro a posterioriVarella, Guilherme January 2015 (has links)
Este trabalho apresenta uma metodologia de otimização topológica visando reduzir o volume de uma estrutura tridimensional sujeita a restrição de tensão. A análise estrutural é feita através do método dos elementos finitos, as tensões são calculadas nos pontos de integração Gaussiana e suavizadas. Para evitar problemas associados a singularidades na tensão é aplicado o método de relaxação de tensão, que penaliza o tensor constitutivo. A norma-p é utilizada para simular a função máximo, que é utilizada como restrição global de tensão. O estimador de erro de Zienkiewicz e Zhu é usado para calcular o erro da tensão, que é considerado durante o cálculo da norma-p, tornando o processo de otimização mais robusto. Para o processo de otimização é utilizada o método de programação linear sequencial, sendo todas as derivadas calculadas analiticamente. É proposto um critério para remoção de elementos de baixa densidade, que se mostrou eficiente contribuindo para gerar estruturas bem definidas e reduzindo significativamente o tempo computacional. O fenômeno de instabilidade de tabuleiro é contornado com o uso de um filtro linear de densidade. Para reduzir o tempo dispendido no cálculo das derivadas e aumentar o desempenho do processo de otimização é proposto um modelo substituto (surrogate model) que é utilizado em iterações internas na programação linear sequencial. O modelo substituto não reduz o tempo de cálculo de cada iteração, entretanto reduziu consideravelmente o número de avaliações da derivada. O algoritmo proposto foi testado otimizando quatro estruturas, e comparado com variações do método e com outros autores quando possível, comprovando a validade da metodologia empregada. / This work presents a methodology for stress-constrained topology optimization, aiming to minimize material volume. Structural analysis is performed by the finite element method, and stress is computed at the elemental Gaussian integration points, and then smoothed over the mesh. In order to avoid the stress singularity phenomenon a constitutive tensor penalization is employed. A normalized version of the p-norm is used as a global stress measure instead of local stress constraint. A finite element error estimator is considered in the stress constraint calculation. In order to solve the optimization process, Sequential Linear Programming is employed, with all derivatives being calculated analiticaly. A criterion is proposed to remove low density elements, contributing for well-defined structures and reducing significantly the computational time. Checkerboard instability is circumvented with a linear density filter. To reduce the computational time and enhance the performance of the code, a surrogate model is used in inner iterations of the Sequential Linear Programming. The present algorithm was evaluated optimizing four structures, and comparing with variations of the methodolgy and results from other authors, when possible, presenting good results and thus verifying the validity of the procedure.
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Aplicação de um modelo substituto para otimização estrutural topológica com restrição de tensão e estimativa de erro a posterioriVarella, Guilherme January 2015 (has links)
Este trabalho apresenta uma metodologia de otimização topológica visando reduzir o volume de uma estrutura tridimensional sujeita a restrição de tensão. A análise estrutural é feita através do método dos elementos finitos, as tensões são calculadas nos pontos de integração Gaussiana e suavizadas. Para evitar problemas associados a singularidades na tensão é aplicado o método de relaxação de tensão, que penaliza o tensor constitutivo. A norma-p é utilizada para simular a função máximo, que é utilizada como restrição global de tensão. O estimador de erro de Zienkiewicz e Zhu é usado para calcular o erro da tensão, que é considerado durante o cálculo da norma-p, tornando o processo de otimização mais robusto. Para o processo de otimização é utilizada o método de programação linear sequencial, sendo todas as derivadas calculadas analiticamente. É proposto um critério para remoção de elementos de baixa densidade, que se mostrou eficiente contribuindo para gerar estruturas bem definidas e reduzindo significativamente o tempo computacional. O fenômeno de instabilidade de tabuleiro é contornado com o uso de um filtro linear de densidade. Para reduzir o tempo dispendido no cálculo das derivadas e aumentar o desempenho do processo de otimização é proposto um modelo substituto (surrogate model) que é utilizado em iterações internas na programação linear sequencial. O modelo substituto não reduz o tempo de cálculo de cada iteração, entretanto reduziu consideravelmente o número de avaliações da derivada. O algoritmo proposto foi testado otimizando quatro estruturas, e comparado com variações do método e com outros autores quando possível, comprovando a validade da metodologia empregada. / This work presents a methodology for stress-constrained topology optimization, aiming to minimize material volume. Structural analysis is performed by the finite element method, and stress is computed at the elemental Gaussian integration points, and then smoothed over the mesh. In order to avoid the stress singularity phenomenon a constitutive tensor penalization is employed. A normalized version of the p-norm is used as a global stress measure instead of local stress constraint. A finite element error estimator is considered in the stress constraint calculation. In order to solve the optimization process, Sequential Linear Programming is employed, with all derivatives being calculated analiticaly. A criterion is proposed to remove low density elements, contributing for well-defined structures and reducing significantly the computational time. Checkerboard instability is circumvented with a linear density filter. To reduce the computational time and enhance the performance of the code, a surrogate model is used in inner iterations of the Sequential Linear Programming. The present algorithm was evaluated optimizing four structures, and comparing with variations of the methodolgy and results from other authors, when possible, presenting good results and thus verifying the validity of the procedure.
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The development of landscape structures affecting biodiversity in the Hanveden and Tyresta green wedgesAndréen, Sigrid January 2015 (has links)
The green wedges of Stockholm are meant to support a high level of biodiversity as well as cultural and recreational services but evaluating the spatial development of the wedges is difficult because their delineation has changed since they were first used in a regional development plan. This study examines a part of the Hanveden and Tyresta wedges in southern Stockholm, with the goal to use robust ecological theory to evaluate the development of the wedges from 1992 until today with focus on conserving a high level of biodiversity. Using an already existing GIS-based method of identifying connectivity weaknesses in the wedges, more weaknesses were found in 2010 than in 1992 although the total area of the wedges had only declined 3.3%. The shape of the wedges had also changed, with more narrow parts in 2010 than in 1992. To more effectively compare the development of factors in the landscape that are relevant for biodiversity, this study proposes a new method using the common shrew and hazel grouse as surrogate species. The total area loss for the common shrew was 2.96% from 1991 to 2013 and 2.23% for the hazel grouse. Fragmentation increased for both species. A large part of the greenspaces relevant to the surrogate species are covered by the green wedges, meaning that important cultural and recreational values identified by the county council are also present in areas relevant to the surrogate species. Using surrogate species to delineate and monitor the green wedges could enhance the cultural and recreational qualities of the wedges, emphasize the need for connectivity planning, identify ecologically important parts of the greenspaces as well as provide a tool for following up the development of the urban greenspaces of Stockholm. However, formulating goals relevant to biodiversity is important to fully evaluate development and municipal cooperation is needed.
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Právní a etické aspekty asistované reprodukce / Legal and ethical aspects of assisted reproductionSoučková, Anna January 2015 (has links)
This thesis deals with legal and ethical aspects of assisted reproduction. The aim of the thesis is to analyse the current legal regulation of assisted reproduction in the Czech Republic, in comparison with the legal system of selected countries. Further aim is to expose the legal regulation's deficits and suggest possible solutions de lege ferenda, particularly with regard to scientific developments and ethical attitudes of the current society. The thesis is divided into six chapters, including the introduction and conclusion. The introductory chapter outlines the issue of assisted reproduction and denotes individual areas on which the thesis will focus. The first chapter deals with the various methods of assisted reproduction and with the term of infertility from the perspective of medical and historical perspective. The second chapter focuses on the legal regulation of individual areas of assisted reproduction in the Czech Republic. Among others, these areas consist of the constitutional protection of the human embryo, the determination of parenthood, the issue of surrogacy, gamete donation and disposition of embryos. The third chapter deals with a comparison of legal framework in selected states. As a representative of the Anglo-American system was chosen United Kingdom of Great Britain and...
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Benthic macroinvertebrate and bryophyte assemblages in boreal springs: diversity, spatial patterns and conservationIlmonen, J. (Jari) 06 April 2009 (has links)
Abstract
In this thesis, I studied the patterns in the assemblage composition as well as the biogeography and ecology of spring macroinvertebrates and bryophytes in Finland. My main objectives were to assess the importance environmental variables to macroinvertebrate and bryophyte assemblage composition in springs at the level of multiple spatial scales. In addition, I assessed the importance of springs in the boreal mire landscape, and sought the ecological and environmental determinants of a key species in boreal springs. In a large-scale study, I also examined the concordance between macroinvertebrates and bryophytes across boreal ecoregions, and assessed how macroinvertebrate assemblage variation corresponds to terrestrially-based ecoregions.
Locally, spring macroinvertebrate assemblage structure displays high variation between different kinds of mesohabitats within springs, highlighting the importance of careful sampling of all habitat types in spring surveys. Helocrenes and other aquatic-terrestrial ecotone habitats harbour the highest species diversity and most spring-dependent species among spring habitat types. Further, spring-influenced mire patches were shown to have distinct cranefly assemblages in the mire landscape and to harbour higher cranefly diversity than mire types with lower trophic status, emphasising the importance of springs for mire biodiversity. Regionally, a red-listed spring-dependent caddisfly species appeared to be a surrogate for a high spring conservation value, indicating high overall species diversity and the occurrence of additional red-listed species.
On a large geographical scale, intersecting the boreal ecoregions, a pattern of gradual change of benthic macroinvertebrate assemblage composition from south to north was detected, largely corresponding to terrestrially-derived ecoregions. However, the physical attributes of springs also need to be taken into account in bioassessment studies. Macroinvertebrate assemblage variation also correlated with physical habitat-scale variables, but not with changes in water chemistry. In contrast, spring bryophyte assemblages showed a distinct response to variation in water chemistry, but not to variation in physical habitat characteristics. Bryophytes and insect assemblages were concordant with each other on the large geographical scale, although the concordance was rather weak. Because of their different kind of responses to the physical and chemical variables, insects and bryophytes of springs are poor surrogates for each other in boreal springs.
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Farinha de vísceras de aves como fonte proteica alternativa na nutrição do dourado, Salminus brasiliensis (Cuvier, 1816) / Poultry byproduct meal as surrogate protein source in diets for dourado, Salminus brasiliensis (CUVIER, 1816)Renan Antunes Donadelli 04 December 2014 (has links)
Alguns peixes carnívoros, como o salmão e a truta, são produzidos mundialmente com rações nutricionalmente completas contendo elevados níveis de farinha e óleo de peixe em função da excelente qualidade nutricional destes ingredientes. A estagnação dos estoques pesqueiros e a demanda crescente por estes ingredientes fazem com que o custo com alimentação de peixes carnívoros seja cada vez mais elevado. Nutricionistas vêm então buscando substituir a farinha e o óleo de peixe nas dietas comerciais, sem prejudicar o desempenho dos peixes confinados. O dourado, Salminus brasiliensis, é um Characiforme ictiófago neotropical de grande porte que apresenta um grande potencial para a aquicultura: excelente qualidade de carne e boa aceitação do mercado consumidor, refletidos em elevado valor comercial, sendo ainda procurado para a pesca esportiva. Entretanto, os estudos sobre o uso da espécie em piscicultura comercial são ainda rudimentares. Os objetivos deste estudo foram avaliar o desempenho do dourado alimentado com dietas contendo a farinha de vísceras em substituição à farinha de peixe e determinar o nível máximo de substituição da farinha de peixes que permitisse a maximização do lucro. O experimento foi realizado em um sistema de recirculação de água com controle de temperatura (26,78 ± 2,21 ºC), oxigênio dissolvido (6,44 ± 1,03 mg L-1), pH (7,40 ± 0,28) e amônia total (<= 0,25 mg L-1). Juvenis de dourado (12,00 ± 0,58 g) foram distribuídos em 24 caixas de polietileno de 300 L (12 peixes por caixa) em um delineamento inteiramente casualizado (n=4), aclimatados às condições de criação e dietas por 10 dias, submetidos a jejum de 24 horas, pesados, medidos e então alimentados em duas refeições diárias por 66 dias com rações extrudadas, nutricionalmente completas (40% de proteína digestível e 4020 kcal kg-1 de energia digestível), com níveis crescentes de farinha de vísceras de aves (0, 20, 40, 60, 80, 100%) em substituição à fonte dietética de proteína, a farinha de peixe. Ao final do período experimental foi feita a biometria para cálculo das seguintes variáveis de desempenho: peso médio final, ganho de peso médio, taxa de crescimento específico, consumo de ração, taxa alimentar, sobrevivência, índice de conversão alimentar, taxa de eficiência proteica, valor produtivo da proteína, eficiência de retenção de energia e maximização do lucro. Embora as variáveis estudadas não apresentassem diferenças significativas (P>0,05), foi observada a presença de dados influentes ou atípicos, que viciaram os resultados da regressão. Para diminuir a influência destes dados na curva da regressão, foi adotado o método da regressão robusta. A análise de maximização do lucro determinou que o nível ótimo de substituição de farinha de peixe por farinha de vísceras de aves foi de 33,29 %. / Carnivorous fish such as trout and salmon are raised on complete feeds, containing large quantities of fish oil and fishmeal, the best quality feed ingredient there is. The stagnation of natural fish stocks and the increasing demand for such feedstuffs makes the cost of carnivorous fish diets increasingly high. Nutritionists are thus in search of alternative ingredients to replace fishmeal in commercial diets without hampering fish performance. The dourado, Salminus brasiliensis, is a Neotropical, large ichthyophagous Characin, highly regarded for fish farming and sport fishing alike because of its prized flesh, high acceptance and market value. However, studies on the farming and husbandry of dourado are still rudimentary. This study evaluates the performance of dourado fed diets formulated to contain increasing levels of poultry byproduct meal in replacement of fish meal and determining the maximum level of replacement of fishmeal that maximizes profit. Trial was set up in a closed loop system, controlled temperature (26.78 ± 2.21 ºC), dissolved oxygen (6.44 ± 1.03 mg L-1), pH (7.40 ± 0.28), and total ammonia (<= 0.25 mg L-1). Juvenile fish were stocked in 24 tanks (300 L, 12 fish per tank) in a completely randomized design (n=4), acclimatized to system conditions and experimental diets for 10 days, fasted for 24 hours, weighted, measured and then fed twice a day for 66 days with extruded, nutritionally complete diets (40% digestible protein and 4020 kcal kg-1 digestible energy), formulated to contain increasing levels of poultry byproduct meal (0, 20, 40, 60, 80, 100) as surrogate protein source to fish meal. At the end of feeding period, fish were measured and weighted (final average weight ) to allow determining average weight gain, specific growth rate, feed consumption, feed conversion rate, protein efficiency rate, productive value of protein, energy retention rate, survival rate and profit maximization. Performance parameters did not differ (P>0.05), so to decrease the effects of influent data, the robust regression method was used and the profit maximization analysis revealed that replacing 33.29% of dietary fishmeal by poultry byproduct meal maximizes profit in the farming of dourado.
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