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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.
151

Memória e história em Espinosa, uma física dos corpos / Memory and History in Spinoza, a physics of bodies

Cátia Cristina Benevenuto de Almeida 06 July 2018 (has links)
Esta pesquisa destina-se à interpretação de memória e história à luz do movimento dos corpos; desse movimento que se estende à intercorporeidade constituem-se os registros ou o que chamamos de marcas corporais, que são as impressões que o corpo retém através de suas relações com os outros corpos. Nossa perspectiva de leitura pretende afastar a base temporal da memória e história para fundamentá-la sob o universo corpóreo. Esse estudo nos permitirá a retomada de dois termos que, a nosso ver, são primordiais para os desdobramentos e afirmação da tese: os vestigia corporis que são justamente as marcas corporais de que estamos falando. Em verdade, os vestigia são, mais uma vez, uma preciosa fonte de investigação e reflexão. Em nossa pesquisa de mestrado eles serviram para pensarmos a superstição; um corpo marcado pelo preconceito e devaneios da imaginação; um corpo marcado pela servidão. Propomos agora que essas mesmas impressões corporais sejam voltadas para pensarmos a Memória, seus usos, coletivo e político, e a História. Essas impressões, portanto, serão nosso principal material. O nosso percurso inicial será apresentar o corpo e os meandros de suas relações, para isso, o recurso à física espinosana, ela nos assegurará que a teoria das marcas fundamente a memória, pois esses registros fixados aos corpos estão submetidos às suas próprias leis. Em função destas marcas é que podemos rememorar, acessar o passado. O recurso às marcas também permitirá que retiremos do tempo o estatuto de guardião absoluto do passado e, portanto, da história. Com isso, poderemos afirmar que a Memória espinosana é também a História, ou seja, são uma e mesma coisa, sobretudo porque se constituem por uma FÍSICA dos corpos. / This research is intended for the interpretation of memory and history in light of the movement of bodies; of this movement of bodies are the registers or what we call body marks, which are the impressions that the body retains through its relations with other body (s). This perspective of reading removes the temporal basis of memory and history, taking them to the bases of the corporeal universe. For this study, we return to two terms that, in our view, are the key to most of our developments throughout the text, as well as within Spinoza\'s philosophy: vestigia corporis. Indeed, these terms are once again a precious source of inquiry and reflection. In our master\'s research the vestigia corporis, which are these marks or bodily impressions, which we have mentioned above, have served to think superstition; a marked body, immersed in prejudices and enveloped by the misunderstandings of the imagination, therefore an easy target to be carried away by the webs of this achievement of the human mind which is superstition. We now propose that these same bodily impressions be turned to thinking of Memory, its uses, collective and political, and History. Our initial course will be to present the body and the intricacies of its relations, for this, the use of the Spinozas physics, it assures us that the theory of marks bases the memory, because they are records fixed to the bodies and submitted their laws; in function of these records is that we can recall, access the past. We need \'material\' so that the memory recognizes itself as such; and where else could this material of recognition and recollection of data be, if not in the human body? In so doing, we will withdraw from time the status of absolute guardian of the past and hence of history. With this, we will affirm that the Spinozas Memory is also History. We can say them, Memory and History in Spinoza are one and the same, above all, because they are constituted by a PHYSICS of bodies.
152

Um estudo sobre a implementação do cálculo diferencial e integral no ensino médio / A study about the implementation of the differential and integral calculus in high school

Jaime Alves de Oliveira Júnior 08 May 2015 (has links)
O objetivo deste trabalho de dissertação foi estudar a importância da implementação do Cálculo Diferencial e Integral no ensino médio. Também houve o interesse em analisar a importância no método utilizado para essa implementação. Especificamente, nos preocupamos em tentar beneficiar os alunos do ensino médio de uma maneira geral, ou seja, os alunos que pretendem continuar seus estudos em nível superior em áreas exatas ou não. Motivados por isto, foi feito um estudo de caso em que se ministrou essa disciplina para dois grupos de alunos do ensino médio (grupos 1 e 2). Para um grupo (grupo 1) a disciplina foi apresentada de maneira mais intuitiva, com muitos exemplos (algébricos ou ligados ao nosso cotidiano) e não muito formal e para o outro grupo (grupo 2) a disciplina foi apresentada de forma mais tradicional e próxima ao abordado no ensino superior. Ao final do nosso estudo verificamos que os dois grupos foram beneficiados, pois tiveram a oportunidade de enriquecer seus conhecimentos através do estudo de uma disciplina muito importante nas áreas de ciências exatas e aplicadas. No entanto, como esperávamos, conseguimos atingir nosso objetivo de maneira mais satisfatória com o grupo 1, pois percebemos que este grupo sempre mostrou mais interesse e, consequentemente, mais facilidade em aprender e aplicar o conhecimento adquirido. Dessa forma concluímos que é possível inserir o Cálculo Diferencial e Integral no ensino médio e que métodos similares ao que utilizamos com o grupo 1 poderão contribuir para qualidade do ensino da matemática no ensino médio, já que oferecem para os alunos um conhecimento mais rico e abrangente da matemática. / The objective of this dissertation was to study the importance of implementing the Differential and Integral Calculus in high school. There has also been interest in analyzing the importance of the method used for its implementation. Specifically, we are concerned in trying to benefit high school students in general, that is, students who intend to continue their studies at a higher level in exact areas or not. Motivated by this, a case study in which they gave this discipline for two high school students groups was made (groups 1 and 2). For a group (group 1) the subject was presented in a more intuitive way, with many examples (algebraic or connected to our everyday) and not too formal and the other group (group 2) the discipline was presented in a more traditional and closely addressed to higher education. At the end of our study we found that both groups benefited, as had the opportunity to enrich their knowledge through the study of a very important discipline in the exact sciences and applied sciences. However, as we expected, we achieved our goal of more satisfactorily with the group 1 because we realize that this group has always shown more interest and, therefore, easier to learn and apply the knowledge gained. Thus we concluded that you can enter the Differential and Integral Calculus in high school and that similar methods to that used with the group 1 may contribute to quality of mathematics teaching in high school, as they provide for students a richer knowledge and embracing of mathematics.
153

Contribuições de trajetórias complexas ao propagador semiclássico para estados coerentes / Contributions of complex trajectories to semiclassical propagator for coherent states

Barreto, Wendell Pereira, 1987- 01 July 2014 (has links)
Orientador: Marcus Aloizio Martinez de Aguiar / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-24T22:36:15Z (GMT). No. of bitstreams: 1 Barreto_WendellPereira_M.pdf: 1811207 bytes, checksum: 0f8c73a79029cd1792710999b0f258a0 (MD5) Previous issue date: 2014 / Resumo: A evolução temporal de estados quânticos é estudada do ponto de vista semiclássico usando o propagador na representação de estados coerentes. No limite semiclássico o propagador pode ser calculado em termos de soluções complexas das equações de Hamilton que devem satisfazer condições de contorno apropriadas. No entanto, nem todas as soluções podem ser utilizadas no cálculo do propagador. Certas trajetórias, denominadas não contribuintes devem ser descartadas, pois dão contribuições incorretas ao propagador. Aqui, exploramos a questão das trajetórias não contribuintes, que é um dos problemas mais sérios na aplicação sistemática das expressões semiclássicas envolvendo órbitas complexas. Para isso consideramos uma classe de problemas unidimensionais não-lineares onde as soluções clássicas e quânticas poder ser obtidas analiticamente. Dessa forma, o propagador semiclássico pode ser escrito de forma explícita, o que permite uma análise detalhada da contribuição de cada trajetória. Definimos então um critério mais preciso para a exclusão de soluções espúrias e, enfim, melhorar o cálculo semiclássico. O sistema foco neste estudo foi o oscilador harmônico ao quadrado, cuja dinâmica tem solução analítica e está presente em problemas de óptica não linear / Abstract: The time evolution of quantum states is studied in the semiclassical limit using the semiclassical propagator in the coherent-state representation. In the semiclassical limit the quantum propagator can be calculated with complex solutions of Hamilton's equations satisfying appropriate boundary conditions. However, not all these solutions can be used in the expression for the propagator. Some trajectories, called non contributing trajectories, give incorrect contributions to the propagator and should be excluded. In this work the issue of non-contributing trajectories, which is one of the most serious problems in the systematic application of semiclassical expression involving complex orbits, is studied. We explore a class of nonlinear one-dimensional problems for which classical and quantum solutions can be analytically obtained. For these problems, the semiclassical propagator can be written explicitty allowing a detailed analisys of the contribution of each trajectory. In this work we will focus on the ''squared harmonic oscillator'', it can be solved analytically and it is present in problems of nonlinear optics / Mestrado / Física / Mestre em Física
154

Tracer pour traverser ? : enquête sur les origines et les fondements de la frontière politique / Drawing a border to cross it? : an investigation into the political border origins and foundations

Esnouf, Jérôme 16 November 2015 (has links)
Assimilées à des fronts arbitraires, les frontières politiques sont devenues à notre époque le signe et le modèle de la limite brutale et injuste. A ne plus vouloir distinguer les groupes humains nous continuons pourtant à les séparer, mais différemment et selon des formes renouvelées du rapport de domination. En supprimant la dimension politique des frontières, ainsi, nous les démultiplions tout en créant des murs et des barrières aux proportions inédites. Notre travail tâche de comprendre comment bien séparer afin de pouvoir mieux unifier. Cela implique de poser certaines questions préalables. Y a-t-il un sens universel et initial au traçage de toute limite dans le sol ? Par quel type d’évolution les limites traditionnelles devinrent-elles des frontières modernes ? Qu’est-ce qu’une frontière au sens pleinement démocratique du terme ? Une frontière n’est pas une limite, car leur légitimité respective n’a pas la même source : une limite se fonde sur une transcendance, tandis que la frontière est auto-référentielle. La raison formelle, en Occident, aura fini par s’imposer à la nature et à la divinité. Il s’agit alors de comprendre le passage historique de l’une à l’autre en suivant les rapports successifs des hommes au symbole, au territoire et au pouvoir. Plus profondément encore, les diverses manières de clore la communauté sociale engagèrent à chaque fois, jusqu’aux prémisses théoriques contemporaines du cosmopolitisme politique, une compréhension renouvelée de son ouverture possible vers les formes diverses de la liberté. Enquêter sur les fondements et les origines de toute séparation politique, en ce sens, revient à retrouver sur le plan historique et normatif à la fois les traces de l’universel concret, celui qui ouvre par la clôture et dont l’idéal est rendu sensible par sa matérialisation dans l’espace. / Considered as arbitrary lines, political borders are today the sign and the model for a brutal and unfair limit. While refusing to distinguish between human groups, we however continue to separate them but on a different manner and according to renewed forms of domination. By suppressing the political dimension of borders, we in fact increase them while creating unprecedented walls and barriers. Our study intends to understand how separating well allows for a better unification. This raises some questions beforehand. Is there a universal and initial meaning to the drawing of any limit on land? Which type of evolution do traditional limits undergo in order to turn into modern borders? What is a border in the fully democratic sense of the term? A border is not a limit because their respective legitimacy does not have the same origin: a limit is based on transcendence whereas a border is self-referential. In the West, formal reason has definitely imposed itself on nature and on the divine. It is then necessary to understand the historical switch from one to the other while studying the successive relations of men to symbol, land and power. On a deeper level, the different ways of containing a social community has always led to a renewed understanding of its possible opening to various forms of freedom, and this up to the theoretical contemporary premises of political cosmopolitanism. Inquiring on the foundations and the origins of any political separation in that sense comes down to track, on an historical and normative level, signs of the concrete universal, the one that opens by closing, and whose ideal is made real by its materialization in space.
155

Effects of dietary energy level and intake of corn by-product based diets on newly received growing cattle

Spore, Tyler J. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Dale A. Blasi / Four pen studies and one digestibility trial were conducted to evaluate the effects of energy level and intake of corn by-product based diets on newly received growing cattle. In Exp.1 there were four diets where one was offered for ad libitum intake and formulated to supply 0.99 Mcal NEg/kg DM (0.99/100) and the other three treatments were fed at 95, 90, and 85% of the ad libitum treatment and to supply 1.10 (1.10/95), 1.21 (1.21/90), and 1.32 Mcal NEg/kg DM (1.32/85), respectively. ADG was unaffected by treatment (P = 0.32). However, G:F increased linearly with increasing energy and decreasing intake level (P < 0.01). In Exp. 2, a digestibility trial was conducted to study diets from Exp. 1. Ruminal propionate linearly increased with increasing dietary energy and decreasing intake (P < 0.01). Total tract DM digestibility increased linearly with increasing energy and decreasing intake (P < 0.01), whereas passage rate decreased (P < 0.01). Experiment 3 validated results from Exp. 1 feeding the 1.10/95 treatment at 2.40% of BW daily and the 1.32/85 treatment at 2.2% of BW daily and studied a DNA-immunostimulant (Zelnate, Bayer Animal Health, Shawnee Mission, KS). Zelnate had no effect on parameters measured. ADG was not different between energy treatments (P = 0.75), but efficiency was greater for the 1.32/85 treatment (P = 0.03). Experiment 4 was designed to observe effects of the 1.32 Mcal NEg/kg DM diet fed at four intake levels of 1.9, 2.2, 2.5, and 2.8 % of BW daily. ADG increased linearly with increasing intake (P < 0.01), however G:F was not affected (P = 0.98). In Exp. 5 a factorial design was employed to evaluate the effects of two by-products; wet corn gluten feed and wet distiller’s grains plus solubles, and two levels of corn processing; whole corn or dry-rolled corn. Final ADG and G:F were not affected by by-product, corn processing, or their interaction (P > 0.30). Additionally, animals and diets from Exp. 1 were used to study effects on antibody production, acute phase protein response, stress, and immunocompetency of healthy and morbid cattle. Diet had no effect on the parameters measured (P > 0.10). A quadratic response to time (P < 0.01) was detected for haptoglobin, titers for bovine viral diarrhea type 1 (BVD-1), and infectious bovine rhinotracheitis (IBR). Haptoglobin was highest on d 14, and close to baseline levels by d 27. Titer levels for BVD-1 and IBR were higher on d 14, and significantly higher on d 27. Titers for bovine viral diarrhea type 2 (BVD- II) responded linearly (P < 0.05) to time with the highest levels on d 27. Haptoglobin was elevated in morbid animals compared to healthy pen mates (P < 0.05). Titer levels for BVD-I and IBR were higher in healthy animals (P < 0.01). Fecal cortisol was higher on arrival than on d 14 (P < 0.05). In summary, high-energy limit-fed diets based on corn by-products do not affect health and are more efficient than when roughage-based growing diets are fed.
156

Investigations into the Shear Strength Reduction method using distinct element models

Fournier, Mathew 11 1900 (has links)
This thesis reports a detailed investigation into the use of the Shear Strength Reduction (SSR) method to determine factor of safety values in discontinuum models using the Universal Distinct Element Code. The SSR method depends on the definition of failure within the model and two different criteria were compared: the numerical unbalanced force definition and a more qualitative displacement-monitoring based method. A parametric study was first undertaken, using a simple homogeneous rock slope, with three different joint networks representing common kinematic states. Lessons learned from this study were then applied to a more complex case history used for validation of the SSR method. The discontinuum models allow for the failure surface to propagate based on constitutive models that better idealize the rockmass than simpler methods such as limit equilibrium (e.g. either method of slices or wedge solutions) and even numerical continuum models (e.g. finite difference, finite element). Joints are explicitly modelled and can exert a range of influences on the SSR result. Simple elasto-plastic models are used for both the intact rock and joint properties. Strain-softening models are also discussed with respect to the SSR method. The results presented highlight several important relationships to consider related to both numerical procedures and numerical input parameters. The case history was modelled similar to how a typical forward analysis would be undertaken: i.e. simple models with complexities added incrementally. The results for this case generally depict a rotational failure mode with a reduced factor of safety due to the presence of joints within the rockmass when compared to a traditional limit equilibrium analysis. Some models with large persistence of steeply dipping joints were able to capture the actual failure surface. Softening models were employed in order to mimic the generation and propagation of joints through the rockmass in a continuum; however, only discontinuum models using explicitly defined joints in the model were able to capture the correct failure surface. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
157

On the Boltzmann equation, quantitative studies and hydrodynamical limits

Briant, Marc January 2014 (has links)
The present thesis deals with the mathematical treatment of kinetic theory and focuses more precisely on the Boltzmann equation. We investigate several properties of the solutions to the latter equation: their positivity and their hydrodynamical limits for instance. We also study the local Cauchy problem for a quantic version of the Boltzmann equation.
158

Path Properties of Rare Events

Collingwood, Jesse January 2015 (has links)
Simulation of rare events can be costly with respect to time and computational resources. For certain processes it may be more efficient to begin at the rare event and simulate a kind of reversal of the process. This approach is particularly well suited to reversible Markov processes, but holds much more generally. This more general result is formulated precisely in the language of stationary point processes, proven, and applied to some examples. An interesting question is whether this technique can be applied to Markov processes which are substochastic, i.e. processes which may die if a graveyard state is ever reached. First, some of the theory of substochastic processes is developed; in particular a slightly surprising result about the rate of convergence of the distribution pi(n) at time n of the process conditioned to stay alive to the quasi-stationary distribution, or Yaglom limit, is proved. This result is then verified with some illustrative examples. Next, it is demonstrated with an explicit example that on infinite state spaces the reversal approach to analyzing both the rate of convergence to the Yaglom limit and the likely path of rare events can fail due to transience.
159

On Resampling Schemes for Uniform Polytopes

Qi, Weinan January 2017 (has links)
The convex hull of a sample is used to approximate the support of the underlying distribution. This approximation has many practical implications in real life. For example, approximating the boundary of a finite set is used by many authors in environmental studies and medical research. To approximate the functionals of convex hulls, asymptotic theory plays a crucial role. Unfortunately, the asymptotic results are mostly very complicated. To address this complication, we suggest a consistent bootstrapping scheme for certain cases. Our resampling technique is used for both semi-parametric and non-parametric cases. Let X1,X2,...,Xn be a sequence of i.i.d. random points uniformly distributed on an unknown convex set. Our bootstrapping scheme relies on resampling uniformly from the convex hull of X1,X2,...,Xn. In this thesis, we study the asymptotic consistency of certain functionals of convex hulls. In particular, we apply our bootstrapping technique to the Hausdorff distance between the actual convex set and its estimator. We also provide a conjecture for the application of our bootstrapping scheme to Gaussian polytopes. Moreover, some other relevant consistency results for the regular bootstrap are developed.
160

Systémy pojištění depozit ve vybraných zemích / Deposit insurance systems in various countries

Lexa, Radek January 2007 (has links)
Práce se zabývá významem ochrany vkladů v bankovním sektoru, věnuje se jednotlivým atributům systémů pojištění vkladů, dává informace o vývoji v ČR a rovněž o integračních tendencích v Evropě i ve světě, dále obsahuje popis vybraných systémů ve světě - srovnání a hodnocení podle některých atributů. Práce také hodnotí různé aspekty kvalitního systému pojištění - jeho efektivnost, spravedlnost a problematiku morálního hazardu. Obsahuje také vymezení síly fondů a jejich role při stabilizaci finančního systému.

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