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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.
121

Atributos físicos e fisiológicos de sementes de aveia preta / Physical and physiological attributes of oat black seeds

Carbonera, Roberto 19 August 2016 (has links)
Forage crops practice an important role in animal production in southern Brazil. Among the species, oat stands out due to its higher crop area in winter, occupying an area of 3.8 million hectares in the state of Rio Grande do Sul. For their proper planting and establishment, seeds are produced which must contain high standards of quality, which is measured by analytical laboratories. Given this, the present study aimed to evaluate the physical and physiological attributes of oat seeds, associating quality seeds to the production profile and the possible effects caused by meteorological factors. Was also designed to identify the variables that correlate with the percentage of pure seed and seedling emergence, identify the presence of multicollinearity, the most important variables in relation to the main dependent variable, percentage of normal seedlings, and group the samples for their degrees of similarity. 2,910 samples were assessed, 2,229 seed analysis derived from the seed production process, 357 analyzes for own use of seeds and 324 analyzes tetrazolium analyzed by the laboratory of the UNIJUÍ Agronomy Course seeds, following the methodology described in the rules seed analysis. The results were submitted to analysis of descriptive statistics, the dispersion of the data, the Pearson linear correlation coefficients were estimated, the diagnosis of multicollinearity, the direct and indirect effects through path analysis and grouping between samples. The seeds produced according to the national seed and seedling system showed excellent levels of physical and physiological quality in the years 2006 to 2010. Between 2011- 2014, 14 and 14.5% of the seeds have been compromised by the presence of other seed species cultivated and tolerated harmful, respectively. The proper use of seeds showed wide variability with 18.1 and 31.7% of samples below the standard for germination in the years 2006 to 2010 and 2011-2014, respectively, while the samples analyzed by the tetrazolium test showed disapproval levels 19.4 and 12.5%, respectively. It is noteworthy that the seed quality is related to the years with levels of rainfall and temperatures appropriate to the vegetative development, physiological maturity and harvest. The variable normal seedlings showed the highest correlation, a negative sign with dead seeds. Abnormal seedlings variables and dead seeds showed the highest direct effects on germination percentage, negative sign and cluster analysis revealed the existence of three similarity groups of seeds produced according to the national system of seed plants and four groups in seed own use. / As plantas forrageiras desempenham importante papel na produção animal na Região Sul do Brasil. Dentre as espécies, a aveia preta se destaca por apresentar maior área de cultivo no inverno, ocupando uma área de 3,8 milhões de hectares no Estado do Rio Grande do Sul. Para a sua adequada semeadura e estabelecimento, são produzidas sementes que devem conter elevados padrões de qualidade, que é aferida por laboratórios de análise. Frente a isso, a presente pesquisa teve como objetivos avaliar os atributos físicos e fisiológicos de sementes de aveia preta, associar a qualidade de sementes ao perfil de produção e aos possíveis efeitos provocados por fatores meteorológicos. Visou, ainda, identificar as variáveis que se correlacionam com a porcentagem de sementes puras e a emergência de plântulas, identificar a presença de multicolinearidade, as variáveis mais importantes em relação à variável dependente principal, porcentagem de plântulas normais, e agrupar a amostras por seus graus de parecença. Foram avaliadas 2.910 amostras, sendo 2.229 análises de sementes oriundas do processo de produção de sementes, 357 análises de sementes de uso próprio e 324 análises de tetrazólio analisadas pelo laboratório de análise de sementes do Curso de Agronomia da UNIJUÍ, seguindo a metodologia descrita nas regras de análise de sementes. Os resultados foram submetidos às análises de estatísticas descritivas, à dispersão dos dados, foram estimados os coeficientes de correlação linear de Pearson, o diagnóstico de multicolinearidade, os efeitos diretos e indiretos através da análise de trilha e o agrupamento entre as amostras. As sementes produzidas segundo o sistema nacional de sementes e mudas apresentaram excelentes níveis de qualidade física e fisiológica nos anos de 2006 a 2010. Entre os anos de 2011 a 2014, 14 e 14,5% das sementes foram comprometidas pelas presenças de outras sementes de espécies cultivadas e de nocivas toleradas, respectivamente. As sementes de uso próprio apresentaram ampla variabilidade com 18,1 e 31,7% de amostras abaixo dos padrão para germinação nos anos de 2006 a 2010 e 2011 a 2014, respectivamente, enquanto que as amostras analisadas pelo teste de tetrazólio apresentaram níveis de reprovação de 19,4 e 12,5 %, respectivamente. Destaca-se que a qualidade fisiológica das sementes está relacionada aos anos com níveis de precipitações e temperaturas adequadas ao desenvolvimento vegetativo, maturidade fisiológica e colheita. A variável plântulas normais apresentou maior correlação, de sinal negativo, com sementes mortas. As variáveis plântulas anormais e sementes mortas apresentaram os maiores efeitos diretos sobre porcentagem de germinação, de sinal negativo e a análise de agrupamento revelou a existência de três grupos de parecença em sementes produzidas segundo o sistema nacional de sementes mudas e de quatro grupos em sementes de uso próprio.
122

Measuring Functional Purity In C# : Developing and implementing a technique for measuring functional purity in C#

Melker, Österberg January 2021 (has links)
Functional purity is a fundamental part of the functional programming paradigm. A function is functionally pure if it is side-effect free and deterministic. Pure functions provide many benefits compared to impure ones, including guaranteed thread-safety as well as easier testing, debugging and maintenance. But how can functional purity be measured? This thesis develops a method for statically measuring the level of functional purity in any given C# program. It also investigates problems with determining purity in object-oriented languages, with a focus on C#. Moreover, a prototype of the method is implemented in order to evaluate the method using a benchmark consisting of 11 open source repositories that use C#'s [Pure] attribute. The [Pure] attribute can be placed in front of a method declaration to indicate that it is side-effect free. Due to a number of limitations to the implementation as well as to [Pure]'s definition of functional purity, which excludes determinism, the results of the evaluation appear relatively poor. After normalizing the implementation's classification distribution for each repository, its classification of pure functions has a precision of 65% and recall 17%, and its classification of impure functions has 54% precision and 69% recall. Nevertheless, the prototype still shows the potential of the full analysis method. A complete implementation of the analysis method could potentially yield a fully working system for measuring any C# program's level of functional purity.
123

Development of Raman and Thomson scattering diagnostics for study of energy transfer in nonequilibrium, molecular plasmas

Lee, Wonchul 07 August 2003 (has links)
No description available.
124

On-line dynamic optimization and control strategy for improving the performance of batch reactors

Mujtaba, Iqbal, Arpornwichanop, A., Kittisupakorn, P. January 2005 (has links)
No / Since batch reactors are generally applied to produce a wide variety of specialty products, there is a great deal of interest to enhance batch operation to achieve high quality and purity product while minimizing the conversion of undesired by-product. The use of process optimization in the control of batch reactors presents a useful tool for operating batch reactors efficiently and optimally. In this work, we develop an approach, based on an on-line dynamic optimization strategy, to modify optimal temperature set point profile for batch reactors. Two different optimization problems concerning batch operation: maximization of product concentration and minimization of batch time, are formulated and solved using a sequential optimization approach. An Extended Kalman Filter (EKF) is incorporated into the proposed approach in order to update current states from their delayed measurement and to estimate unmeasurable state variables. A nonlinear model-based controller: generic model control algorithm (GMC) is applied to drive the temperature of the batch reactor to follow the desired profile. A batch reactor with complex exothermic reaction scheme is used to demonstrate the effectiveness of the proposed approach. The simulation results indicate that with the proposed strategy, large improvement in batch reactor performance, in term of the amount of a desired product and batch operation time, can be achieved compared to the method where the optimal temperature set point is pre-determined.
125

Between honor and shame :|bmartyrdom in 2 Maccabees 6-7 within the socio-cultural arena

Hefer, Barend Joachim January 2012 (has links)
The study, “Between honor and shame: Martyrdom in 2 Maccabees 6-7 within the socio-cultural arena”, presents a look at how the community viewed martyrdom in 2 Maccabees 6:18-7:42 from the perspective of honor and shame. The chief objective is to determine whether or not the community supported or challenged the notion of the martyrs’ death being either honorable or shameful. In order to reach a satisfactory conclusion to this objective, this study set as goals the identification of key themes which shed light upon the views of the community in regard to the martyrs, as well as the investigation of the community’s understanding of honor and shame found in 2 Maccabees 6:18-7:42. This study incorporates a contextual analytical method comprising of an analysis of sociocultural vocabulary, an analysis of the socio-cultural vocabulary within the Greek text of 2 Maccabees 6:18-7:42 and a synthesis of the analysis of both the socio-cultural and the Greek context. As criteria for the study of the socio-cultural context the aspects of sacred-profane, pure-impure, the patron-client relationship and the relationship between individual and group(s) are implemented. Core-findings of this study may be divided into two main categories: evidence in defence of an honorable conduct during death, and evidence in defence of the dishonorable manner of death. Evidence in defence of honorable conduct during death, are: • The martyrs remain completely loyal and devoted to God (their Chief-Patron), His laws and • the customs of the forefathers. • They are portrayed as being bodily whole. • They safeguard their set-apartness. • They remain pure – especially in the ritualistic sense. • As individuals belonging to the collected identity of various groups, the martyrs prove themselves loyal and honorable. Evidence in defence for the dishonorable manner in which the martyrs die, are: • Torture was deemed disgraceful by the community and would therefore degrade honor. • Mutilation went into the very fabric of the wholeness of the body by destroying the bodily unity, thereby disqualifying a person to come into the realm of the sacred. • Certain members of the community would regard the martyrs’ rejection of the lesser patrons’ favor as disrespectful and therefore as dishonorable conduct. Despite this evidence, it is still found that the community could remain undecided on how to judge the martyrs and martyrdom. Therefore, it is proposed, and successfully implemented, that an emotional argument might be the key to tipping the scale toward viewing the martyrs and martyrdom as honorable. It must therefore be concluded that the community would have indeed challenged the notion of martyrdom being honorable, for torture and mutilations in themselves, were regarded as being disgraceful. Yet the community would have been persuaded to accept the honor of the martyrs because of their honorable conduct and the emotional appeal made by the author of Maccabees. / Thesis (MA (Greek))--North-West University, Potchefstroom Campus, 2013.
126

Simulation et optimisation de procédés d'adsorption modulée en pression : formulation et résolution à l'aide de l'optimisation dynamique hybride / Simulation and optimisation of process swing adsorption processes : a hybrid dynamic optimisation approach

Ayoub, Shahid 26 March 2010 (has links)
Dans ce travail, une approche d’optimisation dynamique hybride est développée et utilisée pour simuler et optimiser les procédés d’adsorption modulée en pression (PSA). Elle est principalement basée sur la formulation hybride du modèle du procédé et sur l’utilisation de la méthode du système adjoint.Le problème de simulation qui consiste à déterminer le régime stationnaire cyclique (CSS) est formulé comme un problème d’optimisation où le critère de performance est défini par la condition de CSS, les variables de décision sont données par les valeurs initiales des variables d’état, et les contraintes par le modèle hybride du procédé avec les conditions aux limites associées. En optimisation, le vecteur des variables de décision contient, en plus des valeurs initiales de l’état, les paramètres de dimensionnement et de fonctionnement. La condition de CSS devient, dans ce cas, une contrainte à satisfaire par chaque solution optimale. Plusieurs modèles de procédés, allant du plus simple au plus compliqué, sont ´étudiés.Il s’agit notamment de procédés isothermes et non isothermes avec et sans états gelés. Les critères de performance considérés sont la pureté, la récupération et l´énergie. Les résultats obtenus aussi bien au niveau des performances des procédés considérés que de la robustesse de l’algorithme d’optimisation mis en œuvre, sont tout `a fait intéressants et montrent le grand potentiel de l’approche développée pour le dimensionnement et le fonctionnement optimaux des procédés PSA / The objective of the work was to develop a hybrid dynamic optimisation approach for simulation and optimisation of pressure swing adsorption (PSA) processes. It is mainly based on the hybrid formulation of the process model and on the use of adjoint system method. The simulation problem which consists in determining the cyclic steady state (CSS) is formulated as an optimisation problem where the CSS condition is considered as the performance index, initial values of state variables as decision variables and process model along with associated conditions as constraints. In optimisation, the decision vector consists of design and operation parameters in addition to the initials values of state variables whereas the CSS condition is considered in this case as a constraint to be satisfied for each optimal solution. Several process models with a varied degree of complexity have been studied. These models are isothermal and non isothermal with and without frozen states. The performance index considered are purity, recovery and energy. The results obtained are interesting vis-a-vis the performance of the processes considered as well as the robustness of the optimisation algorithm and show the great potential of the approach developed for the optimal design and operation of PSA processes
127

An algebraic p-adic L-function for ordinary families / Une fonction L p-adique algébrique pour les familles ordinaires

Saha, Jyoti Prakash 11 June 2014 (has links)
Dans cette thèse, nous construisons des fonctions L p-adique algébriques pour les familles de représentations galoisiennes attachées aux familles p-adique analytiques de représentations automorphes en utilisant le formalisme des complexes de Selmer. Ce résultat est obtenu principalement en effectuant une modification des complexes de Selmer pour s’assurer que nous traitons avec des complexes parfaits et démontrer un théorème de contrôle pour les facteurs d'Euler locaux aux places en dehors de p. Le théoréme de contrôle pour les facteurs d'Euler locaux est obtenu par l’étude de la variation de la monodromie sous spécialisations purs des familles p-adiques de représentations galoisiennes restreintes aux groupes de décomposition en dehors de p. Cela nous permet de démontrer un théorème de contrôle pour les fonctions algébriques p-adique que nous construisons pour les familles de Hida de formes paraboliques ordinaires et les représentations automorphes ordinaires pour les groupes unitaires définies. Pour les familles de Hida de formes paraboliques ordinaires, nous construisons un fonction L p-adique algébrique de deux variables et formulons une conjecture la reliant à la fonction L p-adique analytique construite par Emerton, Pollack et Weston. En utilisant des résultats de Kato, Skinner et Urban, nous montrons cette conjecture dans certains cas particuliers. / In this thesis, we construct algebraic p-adic L-functions for families of Galois representations attached to p-adic analytic families of automorphic representations using the formalism of Selmer complexes. This is achieved mainly through making a modification of the Selmer complex to ensure that we deal with perfect complexes and proving a control theorem for the local Euler factors at places not lying above p. The control theorem for local Euler factors is obtained by studying the variation of monodromy under pure specializations of p-adic families of Galois representations restricted to decomposition groups at places of residue characteristic different from p. This allows us to prove a control theorem for the algebraic p-adic L-functions that we construct for Hida families of ordinary cusp forms and ordinary automorphic representations for definite unitary groups. For the Hida family of ordinary cusp forms, we construct a two-variable algebraic p-adic L-function and formulate a conjecture relating it with the analytic p-adic L-function constructed by Emerton, Pollack and Weston. Using results due to Kato, Skinner and Urban, we prove this conjecture in some special cases.
128

Pureté des fibres de Springer affines pour GL_4 / Purity of affine Springer fiber for GL_4

Chen, Zongbin 05 December 2011 (has links)
La thèse consiste de deux parties. Dans la première partie, on montre la pureté des fibres de Springer affines pour $\gl_{4}$ dans le cas non-ramifié. Plus précisément, on construit une famille de pavages non standard en espaces affines de la grassmannienne affine, qui induisent des pavages en espaces affines de la fibre de Springer affine. Dans la deuxième partie, on introduit une notion de $\xi$-stabilité sur la grassmannienne affine $\xx$ pour le groupe $\gl_{d}$, et on calcule le polynôme de Poincaré du quotient $\xx^{\xi}/T$ de la partie $\xi$-stable $\xxs$ par le tore maximal $T$ par une processus analogue de la réduction de Harder-Narasimhan. / This thesis consists of two parts. In the first part, we prove the purity of affine Springer fibers for $\gl_{4}$ in the unramified case. More precisely, we have constructed a family of non standard affine pavings for the affine grassmannian, which induce an affine paving for the affine Springer fiber. In the second part, we introduce a notion of $\xi$-stability on the affine grassmannian $\xx$ for the group $G=\gl_{d}$, and we calculate the Poincaré polynomial of the quotient $\xx^{\xi}/T$ of the stable part $\xxs$ by the maximal torus $T$ by a process analogue to the Harder-Narasimhan reduction.
129

Test of Decay Rate Parameter Variation due to Antineutrino Interactions

Shih-Chieh Liu (5929988) 16 January 2019 (has links)
High precision measurements of a weak interaction decay were conducted to search for possible variation of the decay rate parameter caused by an antineutrino flux. The experiment searched for variation of the <sup>54</sup>Mn electron capture decay rate parameter to a level of precision of 1 part in ∼10<sup>5</sup> by comparing the difference between the decay rate in the presence of an antineutrino flux ∼3×10<sup>12</sup> cm<sup>-2</sup>sec<sup>-1</sup> and no flux measurements. The experiment is located 6.5 meters from the reactor core of the High Flux Isotope Reactor (HFIR) in Oak Ridge National Laboratory. A measurement to this level of precision requires a detailed understanding of both systematic and statistical errors. Otherwise, systematic errors in the measurement may mimic fundamental interactions. <div><br></div><div>The gamma spectrum has been collected from the electron capture decay of <sup>54</sup>Mn. What differs in this experiment compared to previous experiments are, (1) a strong, uniform, highly controlled, and repeatable source of antineutrino flux, using a reactor, nearly 50 times higher than the solar neutrino flux on the Earth, (2) the variation of the antineutrino flux from HFIR is 600 times higher than the variation in the solar neutrino flux on the Earth, (3) the extensive use of neutron and gamma-ray shielding around the detectors, (4) a controlled environment for the detector including a fixed temperature, a nitrogen atmosphere, and stable power supplies, (5) the use of precision High Purity Germanium (HPGe) detectors and finally, (6) accurate time stamping of all experimental runs. By using accurate detector energy calibrations, electronic dead time corrections, background corrections, and pile-up corrections, the measured variation in the <sup>54</sup>Mn decay rate parameter is found to be δλ/λ=(0.034±1.38)×10<sup>-5</sup>. This measurement in the presence of the HFIR flux is equivalent to a cross-section of σ=(0.097±1.24)×10<sup>-25 </sup>cm<sup>2</sup>. These results are consistent with no measurable decay rate parameter variation due to an antineutrino flux, yielding a 68% confidence level upper limit sensitivity in δλ/λ <= 1.43×10<sup>-5</sup> or σ<=1.34×10<sup>-25 </sup>cm<sup>2</sup> in cross-section. The cross-section upper limit obtained in this null or no observable effect experiment is ∼10<sup>4</sup> times more sensitive than past experiments reporting positive results in <sup>54</sup>Mn.</div>
130

Medida do espectro de energia dos nêutrons no núcleo do Reator IPEN/MB-01 / Measurements of the neutron energy spectra in the core of IPEN/MB-01 reactor

Martins, Fernando Prat Gonçalves 24 November 2006 (has links)
Este trabalho apresenta a medida do espectro de energia dos nêutrons no núcleo do Reator IPEN/MB-01. Para tal, foram inseridos detectores de ativação na forma de diminutas folhas metálicas no núcleo do reator, na região moderadora, utilizando um dispositivo articulado que permite que as folhas fiquem posicionadas na posição central do núcleo do reator, garantindo que todas as folhas sejam irradiadas na mesma posição. Os detectores de ativação foram selecionados de forma a cobrir grande parte do espectro de energia dos nêutrons no Reator, para tanto foram utilizadas folhas de Au197, Mg24, Ti48, In115, Sc45 entre outras. Após a irradiação os detectores de ativação foram submetidos a espectrometria gama num sistema de contagem de Germânio hiper-puro, o que possibilitou a obtenção da atividade de saturação por núcleo alvo, um dos principais dados de entrada do código computacional de desdobramento de espectro unfolding SANDBP, que através de um processo iterativo, ajusta o espectro que melhor se adequa ao conjunto de dados de entrada do código, composto principalmente pelas taxas de reação por núcleo alvo obtidas experimentalmente e um espectro inicial de entrada, neste caso obtido à nível celular pelo código Hammer-Technion para a célula representativa do núcleo do Reator, fornecendo assim a solução do espectro. / This work presents the neutron spectrum measurements in the Reactor IPEN/MB- 01 using very thin activation detectors in the metallic form, in reactor core, in moderator region. An articulated device allows that the foils are inserted in the central position of reactor core, ensuring that all the foils are irradiated in the same position. The activation detectors of different materials such Au197, Mg24, Ti48, In115, Sc45 and others, were selected to cover a large range of neutron spectrum. After the irradiation, the activation detectors were submitted to a spectrometry gamma by using a system of counting with high purity Germanium, to obtain the saturation activity per target nuclide. The saturation activity is one of the main data of input of unfolding code SANDBP, that through an iterative adjustment, modify the spectrum that better agree with the dataset of code input, composition mainly for measure reaction rate per target nuclide and a initial input spectrum, calculated for Hammer-Technion code, supplying a solution spectrum.

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