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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.
391

[pt] ESTRATÉGIAS DE APROXIMAÇÕES ANALÍTICAS HIERÁRQUICAS DE PROBLEMAS NÃO LINEARES: MÉTODOS DE PERTURBAÇÃO / [en] STRATEGIES OF HIERARCHICAL ANALYTICAL APPROXIMATIONS OF NON-LINEAR PROBLEMS: PERTURBATION METHODS

MARIANA GOMES DIAS DOS SANTOS 29 April 2019 (has links)
[pt] Problemas dinâmicos governados por problemas de valor inicial (PVI) não lineares, em geral, despertam grande interesse da comunidade científica. O conhecimento da solução desses PVI facilita o entendimento das características dinâmicas do problema. Porém, infelizmente, muitos dos PVI de interesse não têm solução conhecida. Nesse caso, uma alternativa é o cálculo de aproximações para a solução. Métodos numéricos e analíticos são eficientes nessa tarefa e podem fornecer aproximações com a precisão desejada. Os métodos numéricos foram muito desenvolvidos nos últimos anos e amplamente aplicados em problemas de diversas áreas da engenharia. Pacotes computacionais de fácil utilização foram criados e hoje fazem parte dos mais tradicionais programas de simulação numérica. Entretanto, as aproximações numéricas têm uma desvantagem em relação às aproximações analíticas. Elas não permitem o entendimento de como a solução depende dos parâmetros do problema. Visto isso, esta dissertação foca na análise e implementação de técnicas analíticas denominadas métodos de perturbação. Foram estudados os métodos de Lindstedt-Poincaré e de múltiplas escalas de tempo. As metodologias foram aplicadas em um PVI envolvendo a equação de Duffing não amortecida. Programas em álgebra simbólica foram desenvolvidos com objetivo de calcular aproximações analíticas hierárquicas para a solução desse problema. Foi feita uma análise paramétrica, ou seja, estudo de como as condições iniciais e os valores de parâmetros influem nas aproximações. Além disso, as aproximações analíticas obtidas foram comparadas com aproximações numéricas calculadas através do método do Runge- Kutta. O método de múltiplas escalas de tempo também foi aplicado em um PVI que representa a dinâmica de um sistema massa-mola-amortecedor com atrito seco. Devido ao atrito, a resposta do sistema pode ser caracterizada em duas fases alternadas, a fase de stick e a fase de slip, compondo um fenômeno chamado stick-slip. Verificou-se que as aproximações obtidas para resposta do sistema pelo método de múltiplas escalas de tempo têm boa acurácia na representação da dinâmica do stick-slip. / [en] Dynamical problems governed by non-linear initial value problems (IVP), in general, are of great interest of the scientific community. The knowledge of the solution of these IVPs facilitates the understanding of the dynamic characteristics of the problem. However, unfortunately, many of the IVPs of interest does not present a known solution. In this case, an alternative is to calculate approximations for the solution. Numerical and analytical methods are efficient in this assignment and can provide approximations with the desired precision. Numerical methods have been developed over the last years and have been widely applied to dynamical problems in various engineering areas. Computational packages, easy to use, were created and today are part of the most traditional numerical simulation programs. However, numerical approximations have a disadvantage in relation to analytical approaches. They do not allow the understanding of how the solution depends on the problem parameters. Given this, this dissertation focuses on the analysis and implementation of analytical techniques called perturbation methods. The Lindstedt-Poincaré method and multiple time scales method were studied. The methodologies were applied in an IVP involving the non-damped Duffing equation. Symbolic algebra programs were developed with the purpose of calculating hierarchical analytical approximations to the solution of this problem. A parametric analysis was performed, in other words, a study of how the approximations are influenced by initial conditions and parameter values. In addition, the analytical approximations obtained were compared with numerical approximations calculated using the Runge-Kutta method. The multiple scales method was also applied in a IVP that represents the dynamics of a mass-spring-damper oscillator with dry friction. Due to friction, the system response can be characterized in two alternating phases, the stick phase and the slip phase, composing a phenomenon called stick-slip. It was verified that the approximations obtained for system response by the multiple scales method represent the stick-slip dynamics with good accuracy.
392

[pt] DINÂMICA DE UMA COLUNA ROTATIVA ESBELTA SUJEITA À AÇÃO DE STICK-SLIP EM DUAS REGIÕES DISTINTAS / [en] DYNAMICS OF A SLENDER ROTATING COLUMN SUBJECT TO THE STICK-SLIP ACTION IN TWO DISTINCT REGIONS

ADRIANO DOMENY DOS SANTOS 04 May 2016 (has links)
[pt] Este trabalho apresenta um estudo do comportamento dinâmico de uma bancada de testes representativa do sistema real de perfuração, composta por um motor CC acoplado a um sistema físico torcional, sujeita a fontes de atrito que induzem um regime de stick-slip no sistema em duas regiões distintas. O estudo incluiu a identificação de parâmetros da bancada de testes por meio de uma série de ensaios experimentais; e a caracterização do atrito, por meio do levantamento experimental da curva do coeficiente de atrito, em função da velocidade angular dos rotores principais. O intuito inicial foi a obtenção de um modelo numérico que fosse o mais simples possível e que representasse bem a bancada de testes. Uma vez obtido o modelo numérico, prosseguiu-se com uma série de simulações que permitissem uma caracterização indireta do regime de atrito ao qual estivessem submetidos os rotores principais, partindo-se apenas de medições de parâmetros no motor. Esse estudo é de grande relevância para a compreensão qualitativa da dinâmica do sistema real de perfuração, uma vez que ainda hoje não há técnicas totalmente confiáveis para caracterização do comportamento da coluna no fundo do poço a partir de dados da superfície somente. / [en] This paper presents a study of the dynamic behavior of a representative test bench of a real rotary drilling system, comprising a DC motor coupled to a very exible torsional system subjected to sources of friction which can induce self-excitation into two distinct regions of the system. The study includes the identification of parameter settings from the test bench by means of a series of experimental tests and characterization of friction, by obtaining the experimental curve of the friction coefficient as a function of the angular speed of the main rotor. The initial aim was to obtain a numerical model as simple as possible, capable of representing the test bench. Once obtained the numerical model, a series of numerical simulations were done, which allow an indirect characterization of the friction condition to which main rotors were subjected, starting only with the parameters measured at the drive. This study is of great importance for a qualitative understanding of the dynamics of the real drilling system, since today there is no fully reliable techniques to characterize the behavior of the column in the deep from surface data only.
393

Особенности выражения категории пространства в романе Джека Керуака «В дороге» : магистерская диссертация / The expression' features of space category in Jack Kerouac's novel «On the Road»

Ефремова, А. С., Efremova, A. S. January 2024 (has links)
Исследование посвящено особенностям выражения категорий пространства в романе Джека Керуака «В дороге» и их передаче в русских переводах. Актуальность работы обусловлена растущим интересом к исследованиям в области художественного перевода и недостаточной изученностью текстов переводов романа Дж. Керуака «В дороге», в частности, категории пространства. В первой главе рассматривается проблема определения текста в научных исследованиях, выделяются разновидности феномена текстовых категорий и особенности категории пространства, рассматривается специфика художественного перевода. Во второй главе рассматривается история создания романа «On the Road», проводится анализ приемов перевода категории пространства в переводах романа Дж. Керуака. В заключении подводятся итоги исследования. В работе выявляются механизмов передачи пространственных сигналов при художественном переводе. Выявлено, что В. Коган и М. Немцов при передаче категории пространства прибегают к приему калькирования. Однако были выявлены и расхождения в частоте использования тех или иных приемов перевода. Наряду с количественными результатами в ходе анализа удалось обнаружить индивидуально-авторские особенности перевода романа Джека Керуака, а также наиболее частотные приемы перевода категории пространства. / The research is devoted to the peculiarities of space categories' the expression in Jack Kerouac's novel On the Road and their transfer in Russian translations. The relevance of the work is due to the growing interest in research in the field of literary translation and the lack of knowledge of the texts of translations of the novel by J. Kerouac's "On the Road", in particular, the category of space. In the first chapter, the problem of defining text in scientific research is considered, the varieties of the phenomenon of text categories and the features of the category of space are highlighted, the specifics of literary translation are considered. The second chapter examines the history of the creation of the novel "On the Road", analyzes the techniques of translating the category of space in the translations of the novel by J. Kerouac. In conclusion, the results of the study are summarized. The work reveals the transmission's mechanisms of spatial signals in artistic translation. It is revealed that V. Kogan and M. Nemtsov resort to calculus when transferring the category of space. However, there were also discrepancies in the frequency of use of certain translation techniques. Along with the quantitative results, the analysis revealed the individual author's translation features of Jack Kerouac's novel, as well as the most frequent methods of translating the category of space.
394

Aspects du franco-roumanisme culturel et linguistique à la lumière des documents juridico-administratifs des pays roumains (1828-1848)

Cibian, Aura-Celestina 25 February 2012 (has links)
À commencer avec les premiers contacts présentés dans le Chapitre 1, jusqu'à l'essor des relations franco-roumaines, nous avons restitué par cette thèse une image sur la manière dans laquelle a été bâtie et développée l'histoire commune des deux peuples, de sorte que nous pouvons parler finalement du franco - roumanisme en tant que phénomène d'ampleur. Le document sur lequel se basent nos études est la première édition du Règlement Organique, rédigé en alphabet cyrillique, mais la variante qui nous a été très utile est la variante bilingue, roumaine - française, préservée dans les Annales Parlementaires de la Roumanie, 1890. Elle a été une source très riche d'exploitation lexicale, stylistique, morphosyntaxique et de la traduction, aspects abordés dans le Chapitre 3. Celui-ci, nous l'avons structuré en deux parties : théorique, comprenant les principes de deux grands noms de la stylistique, Charles Bally, représentant suisse et Tudor Vianu, représentant roumain et des théoriciens de la traduction parmi lesquels : Georges Mounin, Marianne Lederer, John Catford, Henri Meschonnic, Algirdas-Julien Greimas, Eugene Nida, etc. et pratique, avec des analyses contrastives franco-roumaines, sur des exemples de la variante roumaine – le texte source et la variante française – le texte cible. A la fin de notre thèse, dans le Chapitre 4., nous avons exposé quelques aspects du franco - roumanisme actuel et de la variante actuelle de la Constitution roumaine, variante bilingue qui reflète très bien le saut considérable du XIXe siècle à l'époque actuelle. / Starting with the first contacts mentioned in Chapter 1., to the flourishing of French-Romanian relationships, we have offered through this thesis an image of how has been built and developed the common history of two peoples, so that we can speak afterward of the significant French-Romanian phenomenon. The document that constitutes the basis of our studies is the first edition of the Romanian Constitutional Texts, written in Cyrillic Alphabet, but the version that has been very useful to us is the bilingual French-Romanian version preserved in the 1890 Romanian Parliamentary Annuaries. This has been a very rich source for our lexical, stylistic, morphological, syntactical and translation analysis, aspects presented in Chapter 3. We have structured it into two sections: a theoretical one, having in center two important names in stylistics, Swiss and Romanian representatives, Charles Bally and Tudor Vianu and different translation theoreticians such as: Georges Mounin, Marianne Lederer, John Catford, Henri Meschonnic, Algirdas-Julien Greimas, Eugene Nida, etc.; the second part is a practical one, with contrastive French-Romanian analysis of the two texts: the Romanian text (the source-text) and the French text (the target-text). At the end of our thesis, in Chapter 4, we have detailed some aspects of the nowadays version of the Romanian Constitutional Texts, bilingual version reflecting very well the significant progressive steps taken from the 19th century until now.
395

The induction of novice teachers in community junior secondary schools in Gaborone, Botswana

Dube, Wilhelminah S 30 November 2008 (has links)
This study focuses on the induction of novice teachers in Community Junior Secondary Schools (CJSS) in Gaborone, Botswana. The point of departure is that induction is an important factor that is essential to the success of every beginner teacher. It is the responsibility of the school management to provide comprehensive induction programmes that will support beginner teachers and retain them in the teaching profession. This problem was investigated by means of a literature study and an empirical investigation using a qualitative approach. A small sample of beginner teachers in six selected schools in Gaborone formed the sample for this study. Findings indicated that the extent to which novice teachers are given professional guidance and support in schools is not enough. It is recommended that induction programmes receive more priority in schools since the first year of teaching is the most important determiner in the teaching career of an individual. / Education management / M.Ed. (Education Management)
396

An investigation into factors relating to the reading habits of Indian secondary school pupils in the Phoenix area

Raghunandan, Urmilla 02 1900 (has links)
This research is concerned with an investigation into the factors relating to the reading habits of Indian secondary school pupils in the Phoenix area. It is important to acknowledge that among our youth there are both avid and reluctant readers during and after the period of formal education. It is the group of reluctant readers that has to be lured by the magic of reading. There is a remarkable variation in the reading habits of pupils from the same school. A self-designed questionnaire was administered to 544 boys and girls from standards 6, 7, 8, 9, and 10. The descriptive data available were then analysed and interpreted. The study revealed that the amount of time spent on reading and the number of books read (which together determined reading habits) by pupils was influenced by such factors as home, school, social environment, socioeconomic status, the influence of other media and the personal aspect / Psychology of Education / M. Ed. (Psychology of Education)
397

The South African death sentence under a new constitution

Krautkrämer, Robert Paul Rudolf 06 1900 (has links)
Although s 9 of the new Constitution 1 guarantees the right to life, there is no express provision which abolishes the death sentence. Whereas in the past the death sentence could only be avoided by the exercise of judicial discretion or political and public pressure, its imposition will now have to be entirely re-evaluated. Not only are all the laws of the country subject to the new Constitution, 2 but so too a Constitutional Court will be operational which will have the power to test the constitutionality of any such laws. By looking at the standards and relevant issues which are considered to define the constitutionality of the death sentence internationally, reviewing current application of the death sentence in South Africa, drawing comparisons, and by studying the problems unique to the South African situation, it will be the aim of this dissertation to determine how the death sentence will fare under a Constitutional Court. / Criminal & Procedural Law / LL. M.
398

Invloed van stres op die akademiese prestasie van die volwassene-leerder : 'n orto-andragogiese studie / The influence of stress on the academic performance of the adult learner : an ortho-andragogic study

Lotz, Jan Willem 09 1900 (has links)
Summaries in Afrikaans and English / Text in Afrikaans / Stress is a complex and multi-dimensional phenomenon of which topical significance is given at present. The aim of this study was to focus on the influence of stress on academic performance of the young student. First, a comprehensive study of the literature was undertaken in order to arrive at an understanding of the foregoing. An overview of the nature, etiology and manifestation of stress, as well as how it is coped with, is offered. Special attention was devoted to factors that cause the young student to experience distress. In addition the way in which the personal actualisation of the young student occurs, was researched. From the research it appeared that owing to, among other things, the experiencing of distress and inadequate personal actualisation, some young students are in a situation involving need, which requires urgent and essential ortho-andragogic guidance. Consequently, the ortho-andragogic responsibility of rendering aid within the context of tertiary training was addressed. Lastly, an empirical investigation of the correlation between distress and particularised academically oriented issues was launched. Based on the findings and conclusions arrived at during the course of the study and investigations, recommendations have been made for future research. / Stres is 'n komplekse en veelvlakkige fenomeen wat in die huidige tydsgewrig van aktuele belang beskou word. Die doel van die studie is om die fokus te laat val op die invloed van stres op die akademiese prestasie van die jeugdige student. Ten einde tot begrip van die voorgaande te kom, is daar in eerste instansie 'n omvattende literatuurstudie onderneem. 'n Oorsig is gebied ten opsigte van die aard, etiologie, manifestering en bantering van stres. In die besonder is gelet op faktore wat aanleiding tot distresbelewing by die jeugdige student gee. Benewens die voorgaande, is die wyse waarop die persoonsvoltrekking van die jeugdige student geskied, nagevors. Uit die navorsing het dit geblyk dat sommige jeugdige studente vanwee onder meer distresbelewing en ontoereikende persoonsvoltrekking, in 'n noodsituasie verkeer, wat orto-andragogiese begeleiding noodsaaklik maak. Gevolglik is 'n blik op die orto-andragogiese aanspreeklikheid vir hulpverlening binne tersiere opleidingsverband gewerp. In laaste instansie is 'n empiriese ondersoek na die korrelasie tussen stres en verbesonderde akademiesgeorienteerde aangeleenthede geloods. Na aanleiding van die bevindinge en gevolgtrekkings waartoe daar in die loop van die studie en ondersoek gekom is, ls aanbevelings vir toekomstige navorsing gedoen. / Teacher Education / D. Ed. (Orthopedagogics)
399

De l’espace de jeu au temps du joueur : une épistémologie engagée du jeu en général, et du jeu vidéo en particulier

Bonmati-Mullins, Charlotte 10 1900 (has links)
Pour respecter les droits d’auteur, la version électronique de ce mémoire a été dépouillée de certains documents visuels et audio-visuels. La version intégrale du mémoire a été déposée au Service de la gestion des documents et des archives de l'Université de Montréal. / La constitution du jeu en objet de science et l’institutionnalisation du jeu vidéo font en sorte d’évincer l’essence, et donc le sens du sujet qu’elles entendent définir. L’objet jeu et l’espace de la représentation ludique ont pris le pas sur l’expérience du jouer. Le phénomène jeu reste un objet subjectif: en définissant l’objet, on minimise cette dimension subjective et ses variables expérientielles, et tout particulièrement le temps et le mouvement. En s’appuyant sur des théories pluridisciplinaires telles que la phénoménologie, la sémiologie et la linguistique cognitive, ce mémoire cherche à réhabiliter le temps, le joueur et l’expérience vécue du jouer. Le premier chapitre examine l’ambiguïté du mot jeu, qui renvoie à la fois à l’objet jeu et à l’activité jouer, et interroge la primauté du game sur le play au sein des études du jeu. Le deuxième chapitre questionne la conception dualiste du jeu, telle que véhiculée par le modèle du cercle magique, qui oppose le jeu au réel. Le chapitre trois propose la métaphore conceptuelle du temps suspendu dans l’espace afin d’expliquer d’une part, le rôle structurant de l’espace dans le processus cognitif, et d’autre part la surenchère spatiale des discours vidéoludiques. Finalement, il s’agit de tenir et de maintenir l’équilibre dynamique entre la structure du game et l’expérience du play, et de souligner l’importance de l’unité espace-temps. / The game constitution as an object of science and the institutionalization of the video game oust the essence, and therefore the meaning of the subject they intend to define. The game itself and its playful representation took precedence over the experience of the player. The game phenomenon remains a subjective object: when defining the object, this subjective dimension and its experiential variables are subjectively minimized, especially time and movement. Based on multidisciplinary theories such as phenomenology, semiotics and cognitive linguistics, this paper seeks to rehabilitate the time, the player and the experience of playing. The first chapter examines the ambiguity of the word game, which refers to both the object and the game playing activity, and questions the primacy of game over play in the game studies. The second chapter questions the dualistic conception of game, as conveyed by the magic circle model, which opposes gaming to reality. Chapter three provides the conceptual metaphor of time suspended in space to explain firstly, the structuring role of space in the cognitive process, and also the spatial outbid of the video game discourse. Finally, it is about holding and maintaining the dynamic balance between the gaming structure and the experience of playing, and stress the importance of space-time unity.
400

Un nouveau souffle pour la Biennale de Montréal? Une analyse comparée avec les grandes biennales internationales d'art contemporain

Chouinard, Clara 08 1900 (has links)
Depuis les années 1980-1990, au moment où on assiste, dans le monde de l’art contemporain globalisé, à une prolifération des biennales internationales d’art contemporain, le climat de compétition s’intensifie et l’univers des biennales se phénoménalise et s’homogénéise. Ce mémoire a pour but d’historiciser et de définir les biennales sous leur nature phénoménale afin d’identifier, parmi leur hétérogénéité, un dénominateur commun sous lequel il est possible de comparer ces institutions artistiques en toute légitimité. Le projet étudie ce point de comparaison défini selon les trois critères d’autoévaluation des biennales identifiés dans cette recherche : la globalisation, l’industrie culturelle et touristique, ainsi que l’événementiel et le spectaculaire. Ce mémoire présente comme étude de cas la Biennale de Montréal et son récent renouvèlement. Il fait le point sur la controverse y étant reliée à travers une analyse comparée de la nouvelle Biennale de Montréal et les grandes biennales internationales. / Since the 1980s and 1990s, back when Contemporary Art Biennials were quickly spreading in the Global Artworld, the climate of competition has been intensifying. The world of biennials is becoming more homogenous and more of a phenomenon each year. The current study’s purpose is to historicize and define the biennials according to their phenomenal nature in order to go beyond their heterogeneity and find a common denominator which would allow the comparison of such artistic institutions in a legitimate way. The project will study this point of comparison according to three areas of self-assessment identified for this purpose: globalization, the cultural and touristic industries as well as the entertainment industry. The case study for this research is Montreal’s biennial and its recent renewal. It will explore the controversy related to the subject by analysing and comparing the new Montreal Biennial to the great international biennials.

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