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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.
231

Impacto econômico da densidade nutricional e da idade de abate de frangos de corte / Economic impact of nutritional diet and age of broiler chickens

Amanda da Lapa Silva 12 September 2018 (has links)
Um estudo foi realizado com os objetivos de (i) avaliar o desempenho produtivo, característica de rendimento de carcaça e impacto econômicos de frangos de corte; (ii) demonstrar a utilização de modelos de superfície de resposta em um programa não-linear de formulação de ração para otimização do lucro; e (iii) desenvolver uma planilha dinâmica e interativa para determinar a idade de abate de frangos de corte que otimiza o retorno econômico. Para atender esses objetivos, um experimento foi conduzido, no período de 1 a 56 dias, utilizando 1080 pintos de um dia, Ross®, distribuídos em delineamento em blocos casualizados com seis tratamentos de seis repetições de 30 aves cada. Os tratamentos foram arranjados em esquema fatorial com três densidades nutricionais (baixa, moderada ou alta) por sexos (machos ou fêmeas). Os resultados do desempenho produtivo avaliado, mostraram que a alta densidade nutricional promove melhor desempenho produtivo, entretanto, prejudica os resultados econômicos. Para o fator sexo, as fêmeas apresentam piores resultados de desempenho e econômicos em relação aos machos, no entanto, melhoram o rendimento de peito. No segundo estudo, os modelos de superfície de resposta construídos para as variáveis dependentes consumo de ração e peso corporal para cada sexo e fase de criação foram adequados para estimar o desempenho produtivo e a receita líquida. Além disso, o programa não linear de formulação de ração pode ser útil por otimizar respostas nutricionais e econômicas com precisão. O terceiro estudo fornece uma planilha que usa uma abordagem interativa e dinâmica para determinar a idade de abate que otimiza o lucro da produção baseado no cenário econômico. Os usuários podem calcular a idade ótima de mercado e analisar a decisão de lucro máximo usando diferentes combinações de custos, função de crescimento, equação de consumo de ração e peso de mercado aceitável. Assim, a planilha pode ser aplicada como uma ferramenta de gestão em tempo real para auxiliar na tomada de decisões, otimizar a produtividade animal e maximizar o lucro. / An experiment was conducted with the objective of (i) evaluating the productivity, yield functionality and economic impact of broilers; (ii) demonstrate the use of response surface models in a nonlinear feed formulation program for profit optimization; and (iii) develop a dynamic and iterative programming to determine the optimal slaughter age of broilers that optimizes the profit. For these objectives, an experiment was conducted over a period of 1 to 56 days using 1080 one-day-old Ross® chicks were distributed in a randomized block design with six treatments and six repetitions of 30 birds each. The treatments were arranged in a factorial scheme with three nutritional densities (low, moderate or high) by two sexes (males or females). The production results were evaluated, that high nutritional density promotes optimal productive performance, although it hinders the economic results. Regarding the sex factor, the females showed poor results regarding performance and profit when compared to the males. Nevertheless, they exhibited improved breast meat yields. In the second study, the response surface models were constructed can be used to estimate the productive performance, and therefore the net revenue. In addition, the nonlinear programming of feed formulation can be useful by optimizing nutritional and economic responses accurately. It was concluded that the response surface models are efficient in predicting the performance of broilers and allow to formulate diets to maximize profits. The third study, a dynamic and iterative programming was development for to determine the age slaughter for maximum profit. The model calculated net revenue, consumption ration and market weight. These results could represent a valuable reference for use in adjusting the strategy for broiler production and management. Thus, the developed programming can be applied as a real-time management tool, to aid in decision-making, optimize the productivity and maximize profit.
232

Análise de existência de máxima fase estável de lactato em exercício resistido em população jovem e idosa / Maximal lactate steady analysis in resistance exercise in young and older groups

Nuno Manuel Frade de Sousa 27 October 2010 (has links)
A máxima fase estável do lactato (MFEL) é considerada uma intensidade critica em exercício dinâmico e sua intensidade é específica do grupo etário. No entanto, apesar da relação existente entre a intensidade de esforço e os ajustes cardiovasculares, metabólicos e ventilatórios durante o exercício resistido, a MFEL foi muito pouco estudada neste tipo de exercício. O objetivo do estudo foi verificar e comparar a existência de MFEL nos exercícios leg press (LP) e supino reto (SR) em dois grupos: jovens e idosos. Além disso, analisar o comportamento das variáveis ergoespirométricas (VE, VO2 e VCO2), lactacidemia, freqüência cardíaca (FC), pressão arterial (PA) e percepção subjetiva de esforço (PSE) na intensidade da MFEL. Foram avaliados 13 homens jovens (26,1 +/- 2,9 anos) e 11 idosos (68,9 +/- 4,0 anos) saudáveis e com experiência mínima de 6 meses em treinamento resistido, que passaram por teste de 1 repetição máxima (1RM), teste crescente para determinação do limiar anaeróbio (LAn) e mais três sessões para a determinação da MFEL. Todas as sessões foram realizadas no mesmo horário do dia, separadas por 48 a 72 horas de intervalo. O LAn, expresso em %1RM, foi significativamente superior no LP em relação ao SR para os dois grupos estudados (LP: 27,8 +/- 3,6 %1RM nos jovens e 27,9 +/- 5,0% 1RM nos idosos; SR: 24,0 +/- 3,0% 1RM nos jovens e 21,5 +/- 3,1% 1RM nos idosos). Não foram observadas diferenças estatisticamente significativas na intensidade do LAn entre os grupos em cada aparelho. A lactacidemia na intensidade do LAn foi significativamente inferior no LP (1,86 +/- 0,63 mmol/L nos jovens e 1,23 +/- 0,34 mmol/L nos idosos) em relação ao SR (2,08 +/- 0,41 mmol/L nos jovens e 1,91 +/- 0,40 mmol/L nos idosos). A intensidade da MFEL no grupo de jovens foi 29,2 +/- 6,7% 1RM no LP e 21,7 +/- 4,4% 1RM no SR. No grupo e idosos, a MFEL ocorreu a 30,9 +/- 4,9% 1RM no LP e 23,3 +/- 6,6% 1RM no SR. A MFEL ocorre em intensidade significativamente menor no aparelho SR para os dois grupos (p < ou = 0,05), sem diferenças estatisticamente significativas entre os grupos. Não houve diferença significativa entre as intensidades do LAn e da MFEL para os dois grupos nos dois aparelhos. Durante a realização do exercício na MFEL, ocorreu a estabilização dos parâmetros ergoespirométricos, FC, PA e PSE entre a série 9 e série 15. Estes resultados demonstram que é possível determinar MFEL nos exercícios LP e SR para as duas populações estudadas. A MFEL ocorre em intensidades superiores no exercício LP. A intensidade da MFEL, expressa em percentual de 1RM, é semelhante à intensidade do LAn. / The maximal lactate steady state (MLSS) is considered a critical intensity of dynamic exercise and its intensity is specific to the age group. However, despite the relationship between exercise intensity and cardiovascular, metabolic and ventilatory adjustments during resistance exercise, the MLSS was unknown in this type of exercise. The purpose of the study was to verify and to compare if there is a maximal lactate steady state (MLSS) for leg press (LP) and bench press (BP) exercises in two different groups: young and older people. Furthermore, to evaluate the ventilatory responses (VE, VO2 e VCO2, blood lactate concentration (BLC), heart rate (HR), blood pressure and rate of perceived exertion (RPE) to those exercises performed on MLSS intensity. 13 young men (26,1 +/- 2,9 years) and 11 elderly healthy men (68,9 +/- 4,0 years) with a minimal experience of 6 months of resistance training volunteered for the study. Volunteers underwent a 1 repetition maximum test (1RM), an incremental test to determine anaerobic threshold (AT) and three more sessions to determine MLSS. Session were performed on the same time of day and separated by a 48-72 h interval. AT intensity (%1RM) was significantly higher for LP than BP for the two groups studied (LP: 27,8 +/- 3,6% 1RM for young group and 27,9 +/- 5,0% 1RM for elderly; BP: 24,0 +/- 3,0%1RM for young group and 21,5 +/- 3,1%1RM for elderly). There was no significant difference between groups in the AT intensity. BLC on AT was significantly lower for LP (1,86 +/- 0,63 mmol/L for young group and 1,23 +/- 0,34 mmol/L for elderly) than BP (2,08 +/- 0,41 mmol/L for young and 1,91 +/- 0,40 mmol/L for elderly). MLSS intensity for young group was 29,2 +/- 6,7% 1RM in LP and 21,7 +/- 4,4% 1RM in BP. For elderly, MLSS was 30,9 +/- 4,9% 1RM in LP and 23,3 +/- 6,6% 1RM in BP. MLSS intensity was significantly lower in BP for both groups (p < or = 0,05), with no statistical differences between groups. There was no significant difference between AT and MLSS intensities on both groups. During exercise on MLSS, ventilatory parameters, HR, blood pressure and RPE stabilized between set 9 and set 15. These results show that it is possible to identify MLSS on the LP and BP exercises for both populations. MLSS intensity is higher in LP exercise, when compared to BP. MLSS intensity is similar to the AT intensity.
233

Ensaio clínico randomizado de uma intervenção educacional no exercício físico e na qualidade de vida de crianças e adolescentes com fibrose cística

Hommerding, Patrícia Xavier January 2011 (has links)
Objetivos: O exercício físico regular em pacientes com fibrose cística (FC) auxilia no condicionamento aeróbico e diminui a progressão da doença, proporcionando melhor qualidade de vida. O objetivo desse estudo foi avaliar os efeitos de um programa de exercício físico aeróbico baseado na orientação verbal e instrumental na capacidade funcional e na qualidade de vida. Métodos: O Estudo constituiu-se de um ensaio clínico, randomizado, de orientações para o exercício físico realizado em um centro de FC. Os pacientes foram alocados em dois grupos, intervenção e controle, sendo 17 pacientes no grupo intervenção (G1) e 17 para o grupo controle (G2). A coleta de dados ocorreu durante o período de outubro de 2010 a outubro de 2011, e a população em estudo consistiu em crianças e adolescentes com FC e idade entre sete e 20 anos.A intervenção foi um manual de orientações com exercícios físicos aeróbicos e reforço das orientações por meio de contato telefônico a cada duas semanas. Resultados: Foram estudados 34 pacientes com FC, sendo que 20 pacientes (58,8)% eram do sexo masculino. Os grupos eram semelhantes no momento basal, sendo que no G1 seis pacientes (35,2%) referiram praticar exercício físico regularmente, a média de idade foi de 13,40±2,81 anos, do percentual do previsto do volume expiratório forçado no primeiro segundo (VEF1%) foi de 95,53±17,94 % e do consumo de oxigênio de pico relativo a massa corporal (VO2pico) foi de 34,93±9,09 ml/kg-1.min-1 . No G2, quatro pacientes (23,5%) referiram praticar exercício físico regularmente, a média de idade foi de 12,76±3,37 anos, do VEF1 foi de 100,13±21,27 % e do VO2pico foi de 33,21±8,26 ml/kg-1.min. Houve aumento significativo do G1 na prática de exercício físico relatada pelos pacientes após os três meses de intervenção comparado ao G2 (p=0,013). Nas demais variáveis não foram observadas diferenças estatisticamente significativas. Conclusão: Esse estudo demonstrou que a orientação verbal e instrumental para o exercício aeróbico, acoplado com supervisão telefônica teve impacto positivo no relato das crianças e adolescentes quanto a prática do exercício físico regular. Porém, não foram observados melhora nos parâmetros fisiológicos, nem nos domínios do questionário de qualidade de vida. / Objectives: Regular physical activity in patients with cystic fibrosis (CF) improves aerobic conditioning and delays disease progression, which results in better quality of life. This study evaluated the effect on functional capacity and quality of life of an aerobic physical activity program based on verbal and written guidelines. Methods: This randomized clinical trial used guidelines for physical exercise in a CF center. Patients were assigned to two groups: intervention (G1), with 17 patients; and control (G2), also with 17 patients. Data were collected from October 2010 to October 2011, and the study population comprised children and adolescents with CF aged 7 to 20 years. The intervention consisted of handing out a manual with guidelines for aerobic physical exercises and reinforcing recommendations in contacts by phone every two weeks. Results: Thirty-four patients were included in the study, 20 of whom were boys (58.5%). The groups were similar at baseline. In G1, 6 patients (35.2%) reported practicing physical exercises regularly; mean age was 13.40±2.81 years, mean percent predicted forced expiratory flow at one second (FEV1%) was 95.53±17.94% and mean peak oxygen uptake (VO2peak) relative to body mass was 34.93±9.09 ml/kg-1.min-1. In G2, four patients (23.5%) reported practicing physical exercises regularly. Mean age was 12.76±3.37 years, mean FEV1 was 100.13±21.27% and mean VO2peak was 33.21±8.26 ml/kg-1.min. In G1, there was a significant increase of physical exercise practice as reported by patients after three months of intervention when compared with G2 (p=0.013). No statistically significant differences were found for the other variables. Conclusion: Verbal and written guidelines for aerobic exercise, together with supervision over the phone, had a positive impact on the report of regular physical exercise practice by children and adolescents. However, no improvement was found in physiological parameters or domains of the quality of life questionnaire.
234

Applications of Degree Theories to Nonlinear Operator Equations in Banach Spaces

Adhikari, Dhruba R 26 April 2007 (has links)
Let X be a real Banach space and G1, G2 two nonempty, open and bounded subsets of X such that 0 ∈ G2 and G2 ⊂ G1. The problem (∗) T x + Cx = 0 is considered, where T : X ⊃ D(T) → X is an accretive or monotone operator with 0 ∈ D(T) and T(0) = 0, while C : X ⊃ D(C) → X can be, e.g., one of the following types: (a) compact; (b) continuous and bounded with the resolvents of T compact; (c) demicontinuous, bounded and of type (S+) with T positively homogeneous of degree one; (d) quasi-bounded and satisfies a generalized (S+)-condition w.r.t. the operator T, while T is positively homogeneous of degree one. Solutions are sought for the problem (∗) lying in the set D(T + C) ∩ (G1 \ G2). Nontrivial solutions of (∗) exist even when C(0) = 0. The degree theories of Leray and Schauder, Browder, and Skrypnik as well as the degree theory by Kartsatos and Skrypnik for densely defined operators T, C are used. The last three degree theories do not assume any compactness conditions on the operator C. The excision and additivity properties of these degree theories are employed, and the main results are significant extensions or generalizations of previous results by Krasnoselskii, Guo, Ding and Kartsatos involving the relaxation of compactness conditions and/or conditions on the boundedness of the operator T. Moreover, a new degree theory developed by Kartsatos and Skrypnik has been used to prove a similar result for operators of type T + C, where T : X ⊃ D(T) → 2 X∗ is a multi-valued maximal monotone operator, with 0 ∈ D(T) and 0 ∈ T(0), and C : X ⊃ D(C) → X∗ is a densely defined quasi-bounded and finitely continuous operator of type (S˜+). The problem of existence of nonzero solutions for T x + Cx + Gx 3 0 is also considered. Here, T is maximal monotone, C is bounded demicontinuous of type (S+), and G is of class (P). Eigenvalue and invariance of domain results have also been established for the sum L + T + C : G ∩ D(L) → 2 X∗ , where G ⊂ X is open and bounded, L : X ⊃ D(L) → X∗ densely defined linear maximal monotone, T : X → 2X∗ bounded maximal monotone, and C : G → X∗ bounded demicontinuous of type (S+) w. r. t. D(L).
235

De la composition de systèmes temporisés

Bornot, Sébastien 15 December 1998 (has links) (PDF)
La composition des systèmes temporisés est source de nombreux problèmes, notamment de blocage. Nous proposons un cadre de description compositionnelle des systèmes temporisés qui préserve la réactivité temprorelle, à savoir que si le système ne peut réagir, alors le temps peut avancer. Nous effectuons d'abord une étude préliminaire sur la spécification des évolutions temporelles dans les systèmes, débouchant sur la définition de mécanismes de description adéquats. Ceci nous permet de définir une classe de modèles temporisés temporellement réactifs, par construction. Nous définissons sur cette classe des opérateurs de choix et de composition parallèle qui préservent cette propriété. En outre, les opérateurs sont définis de sorte à préserver l'activité dans le sens où si à partir d'un état une action est possible dans un composant, alors une action est possible dans la composition. L'opérateur de composition parallèle respecte également la propriété de progrès maximal grâce à l'utilisation d'opérateurs de choix avec priorités qui favorise les synchronisations. Un cadre général est donné pour exprimer différents modes de synchronisation, parmi lesquels on retiendra AND (synchronisation classique), MAX (synchronisation avec attente) et MIN (interruption). Pour terminer, nous développons une approche algébrique pour une sous-classe des modèles considérés.
236

Détection et suivi d'objets en mouvement dans des scenes complexes, application a la surveillance des conducteurs.

Bugeau, Aurélie 20 December 2007 (has links) (PDF)
De nombreuses applications en vision par ordinateur nécessitent la détection et le suivi des objets en mouvement dans une séquence d'images. La plupart des méthodes existantes ne donnent de bons résultats que pour des séquences avec des fonds peu changeants, ou si le fond et les objets sont rigides. Le but de cette thèse est de détecter et suivre les objets mobiles dans des séquences (telles que des séquences de conducteurs) ayant un fond dynamique, avec de forts changements d'illumination, de faibles contrastes et éventuellement acquises par une caméra mobile. Cette thèse est décomposée en deux parties. Dans la première, une méthode de détection est proposée. Elle repose sur la définition d'une grille de points décrits par leur mouvement et leur photométrie. Ces points sont ensuite regroupés en "clusters en mouvement" avec un algorithme mean shift à noyau variable et une méthode de sélection automatique de la taille des noyaux. La deuxième partie propose une méthode de suivi combinant des distributions de couleur et de mouvement, la prédiction de l'objet et des observations extérieures (pouvant être les clusters en mouvement) dans une fonction d'énergie minimisée par coupe minimale/flot maximal dans un graphe. Les algorithmes de détection et de suivi sont validés sur différentes séquences aux contenus dynamiques complexes.
237

Ideals and Boundaries in Algebras of Holomorphic Functions

Carlsson, Linus January 2006 (has links)
<p>We investigate the spectrum of certain Banach algebras. Properties</p><p>like generators of maximal ideals and generalized Shilov boundaries are studied. In particular we show that if the ∂-equation has solutions in the algebra of bounded functions or continuous functions up to the boundary of a domain D ⊂⊂ C<sup>n</sup> then every maximal ideal over D is generated by the coordinate functions. This implies that the fibres over D in the spectrum are trivial and that the projection on Cn of the n − 1 order generalized Shilov boundary is contained in the boundary of D.</p><p>For a domain D ⊂⊂ C<sup>n</sup> where the boundary of the Nebenhülle coincide</p><p>with the smooth strictly pseudoconvex boundary points of D we show that there always exist points p ∈ D such that D has the Gleason property at p.</p><p>If the boundary of an open set U is smooth we show that there exist points in</p><p>U such that the maximal ideals over those points are generated by the coordinate functions.</p><p>An example is given of a Riemann domain, Ω, spread over C<sup>n</sup> where the fibers over a point p ∈ Ω consist of m > n elements but the maximal ideal over p is generated by n functions.</p>
238

Why is there still so much confusion about VO2 plateau? A re-examination of the work of A.V. Hill

Castle, Richard Vincent 01 June 2011 (has links)
Maximal oxygen uptake (VO2max) is regarded as the gold standard for assessing aerobic fitness. In 1923, Hill et al. proposed that VO2max represents the maximal ability of the body to take in and consume O2 during strenuous exercise. Recently, however, controversy has arisen over the issue of whether a leveling off, or "plateau" in VO2 is necessary to verify attainment of VO2max. Purpose: To compare two different VO2max protocols and determine if both protocols show direct evidence of an upper limit on VO2. Methods: Nine runners (18-35 years old) completed a continuous graded exercise test (CGXT), followed by a discontinuous graded exercise test (DGXT). The CGXT consisted of gradually increasing treadmill running speed to the point of volitional exhaustion; the highest speed attained was labeled the peak treadmill speed. Over the next several days, participants ran at 80%, 90%, 100%, 105%, and 110% of peak treadmill speed for 10 minutes, or until volitional exhaustion was reached. Results: All participants (n=9) achieved a "VO2 ceiling" (or upper limit) on the DGXT, while only 44% (n=4) achieved a "VO2 plateau" on the CGXT. There was no significant difference between the VO2max obtained from a CGXT (57.4 ± 2.6 mL*kg-1min-1) and DGXT (60.0 ± 3.1 mL*kg-1min-1). There was no difference between oxygen uptake measured at 90%, 100%, 105%, and 110% of PTV (p>0.05). However, the highest VO2 recorded at 80% PTV was significantly lower than that recorded at all other velocities (p<0.05). Conclusion: The VO2 ceiling effect on a DGXT is inherently different than the VO2 plateau effect on a CGXT. In this study, a ceiling was always seen on the DGXT, but a plateau was not always seen on the CGXT.
239

Ideals and boundaries in Algebras of Holomorphic functions

Carlsson, Linus January 2006 (has links)
We investigate the spectrum of certain Banach algebras. Properties like generators of maximal ideals and generalized Shilov boundaries are studied. In particular we show that if the ∂-equation has solutions in the algebra of bounded functions or continuous functions up to the boundary of a domain D ⊂⊂ Cn then every maximal ideal over D is generated by the coordinate functions. This implies that the fibres over D in the spectrum are trivial and that the projection on Cn of the n − 1 order generalized Shilov boundary is contained in the boundary of D. For a domain D ⊂⊂ Cn where the boundary of the Nebenhülle coincide with the smooth strictly pseudoconvex boundary points of D we show that there always exist points p ∈ D such that D has the Gleason property at p. If the boundary of an open set U is smooth we show that there exist points in U such that the maximal ideals over those points are generated by the coordinate functions. An example is given of a Riemann domain, Ω, spread over Cn where the fibers over a point p ∈ Ω consist of m &gt; n elements but the maximal ideal over p is generated by n functions.
240

From The Epic To The Novel: A Comparative Study Of Beowulf And Grendel

Dalbak, Emine 01 July 2003 (has links) (PDF)
This thesis compares the Anglo-Saxon epic Beowulf and John Gardner&amp / #8217 / s novel Grendel in terms of their generic relations within a framework of Bakhtin&amp / #8217 / s genre theory. The analysis restricts its theoretical framework to basically two essays by Mikhail M. Bakhtin, namely Epic and Novel and Discourse in the Novel included in Michael Holquist&amp / #8217 / s The Dialogic Imagination: Four Essays by M. M. Bakhtin (1981). This study argues that Beowulf represents a monologic world, which is hierarchically distanced from the present. As Bakhtin puts it, the epic presents an already completed world placed in an absolute past, which demands a pious attitude as it is hierarchically above the reader. Gardner&amp / #8217 / s Grendel, on the other hand, is a retelling of the Beowulf story through the monster&amp / #8217 / s eye in the contemporary world. It suggests a dialogue between the elevated world of the epic hero Beowulf and the novelistic world of Grendel to achieve multiplicity in a truly Bakhtinian sense. For Gardner&amp / #8217 / s version enables the monstrous other, which is Grendel, to raise its voice. By changing the temporal order and narrative perspective, Gardner succeeds in re-writing an epic story in the novelistic zone of maximal proximity to the present. This thesis, however, argues that although Gardner&amp / #8217 / s Grendel displays all the novelistic features, basically multiplicity and contemporaneity, as put forward by Bakhtin, it still celebrates the ideal world of the epic.

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