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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.
471

Overvoltages and coupling effects on an ac-dc hybrid transmission system

Verdolin, Rogerio 05 1900 (has links)
Abstract Adding a dc circuit to an existing transmission line is one method of significantly increasing the power transfer capability of a transmission corridor. The resulting hybrid system has significant coupling between the ac and dc circuits, not only because of the proximity of the circuits, but also from the fact that they may share the same sending end or receiving end ac systems. The resultant interaction produces overvoltages on the dc system which can be somewhat higher than for a conventional dc scheme. This thesis investigates the overvoltages on a hybrid ac-dc transmission system and suggests some design considerations which could be taken into account to reduce stresses on certain critical components which result from such an arrangement. Blocking filters consisting of a parallel L-C combination in series with the dc converter were included to limit the flow of fundamental frequency current in the dc line. This thesis also investigates the proper blocking filter configuration to be used as an incorrectly chosen blocking filter can cause resonance overvoltages on the dc line at fundamental frequency. A method of eliminating dc components of the currents in the transformer windings of a dc converter is presented. The method uses the technique of firing angle modulation. It is shown that merely eliminating the fundamental frequency component on the dc side may not remove this dc component. The impact of such control action at one converter on the other converters in the dc transmission system is also presented. It is also shown that the undesirable side effects of such a scheme include increased generation of non-characteristic harmonies on both the ac and dc sides. The study is performed using an electromagnetic transients simulation program and theoretical calculations.
472

The organizing and the balance between profession and profit in the Big Four accounting firms / Organiseringen och balansen mellan profession och vinst inom de Big Four revisionsbyråerna

Hsiung, Sanna January 2013 (has links)
Title: The organizing and the balance between profession and profit in the Big Four accounting firms Introduction: Globalization has lead to a world with increasing similarities and a larger market where only efficient organizations survive why information is important for survival and success. Accounting firms fulfill an important role by securing information and contribute to the prosperity of society through an efficient market. But they differ both from non-PSF and among each other due to the need of managing the balance between profession and profit. The current research on accounting firms is limited and lacking. This thesis contributes to the current research by providing a new perspective to the existing research on accounting firms. Purpose: The purpose of this thesis is to understand how the Big Four accounting firms organize in order to manage the balance between profession and profit. Method: The thesis uses a qualitative research method in which data and information is collected from financial statements and websites that is compiled into multiple case studies on the Big Four accounting firms to give a detailed description of how they organize to manage the balance between profession and profit. Conclusions: The result demonstrates that there are similarities between how the Big Four accounting firms organize to manage the balance between profession and profit. The thesis moreover shows that there are connections between the factors of organizing (goal, environment, strategy and structure latter of which is divided in organizational structure, partnership, knowledge, reward system, informal and formal management processes and responsibility distribution) and the balance between profession and profit which indicates that the Big Four accounting firms considers the balance between profession and profit in the organizing for the survival and success in the market.
473

The perceptions of a group of first year undergraduate Malawian students of the essay writing process

Kalikokha, Chimwemwe January 2008 (has links)
The purpose of this study was to explore the perceptions of the essay writing process of first year undergraduates at Chancellor College (University of Malawi) and to a lesser extent those of the lecturers responsible for teaching academic skills. A mixed methods design, combining qualitative and quantitative techniques, was employed in order to obtain richer data for deeper understanding of the students’ writing process. Two hundred students from the humanities and social science faculties responded to a self-completion questionnaire towards the end of semester one. Based on the students’ responses, an open-ended questionnaire was administered to four full time English for Academic Purposes (EAP) instructors. Findings from this study indicate that most students find it very challenging to obtain sufficient and relevant source text information, paraphrase or summarise information, and use an appropriate academic writing style. As solutions to these challenges, the students suggested the need for timely essay writing instruction, availability of resources for essay writing, increased amount of time spent on essay writing instruction, and discipline specific instruction in essay writing. EAP instructors identified lack of teaching and learning materials, large EAP classes, and students’ negative attitude towards the EAP course, as some of the challenges they encounter when teaching the course. The EAP instructors proposed an increase in the number of staff members, making students aware of the significance of the EAP course at an early stage, and the availability of up to date resources, as some of the ways in which the teaching of the course can be improved. Overall, the findings seem to suggest that difficulties that students encounter during the writing process and teaching challenges that EAP instructors face, have great impact on students’ perception of academic writing as well as their approach to writing tasks. The findings also suggest a lack of dialogue between the students and their lecturers. This is evident in students’ unawareness of the nature of the writing demands of their lecturers and disciplines; students’ desire to have timely essay writing instruction; and the lecturers’ concerns about students’ negative attitude towards the EAP course.
474

Des communautés et des sports au Liban : enjeux des regroupements sportifs et des rencontres intercommunautaires / Communities and sports in Lebanon : stakes in the sports groupings and in the intercommunity meetings

Nseir, Georges 13 January 2012 (has links)
Selon une opinion commune couramment répandue dans les pays occidentaux, le sport institué serait une école d’apprentissage, du sens du collectif, de la solidarité, du partage et des règles de vie : en bref, il socialiserait naturellement les jeunes en les intégrant dans la société. Cette recherche nous a amené à nous intéresser aux formes de socialisation que la société libanaise offre aux « sportifs ». Si le fait de penser le sport d’une part comme apolitique et, d’autre part, comme une passion partagée par l’ensemble de la jeunesse ne date pas d’aujourd’hui, cette question se lit différemment au Liban, pays qui a subi des conflits internes et régionaux depuis plus de 500 ans. Organisé politiquement et socialement en « communautés », le Liban propose ainsi un modèle politique à base religieuse qui imprègne la vie quotidienne des libanais, y compris au sein du monde sportif. Chaque communauté est gouvernée par une autorité spécifique, régie par ses institutions et soumise à une juridiction autonome formée de membres appartenant à la hiérarchie religieuse, à laquelle l’Etat a reconnu la compétence d’appliquer ses lois et coutumes. Mis à l’épreuve du terrain, ce constat est pourtant à relativiser. L’enquête révèle que les clivages communautaires affectent profondément les instances de gestion des fédérations sportives et provoquent une répartition confessionnelle dans les comités de direction. Cependant, dans le sport comme dans d’autres domaines de la vie sociale, la communauté n’est jamais « pure » et l’on observe aussi des coalitions intercommunautaires dans le but de conquérir le pouvoir sportif. Partant d’une approche macrosociologique, la thèse propose d’étudier le regroupement communautaire dans le sport associatif à travers deux monographies de club réalisées à Beyrouth afin d’analyser ces dynamiques confessionnelles: le Ryadi, à dominante confessionnelle musulmane, et son pendant chrétien, le club de la Sagesse. L’analyse sociologique montre à voir deux micro sociétés qui pratiquent « l’entre soi » sportif mais qui, dans le même temps, présentent une ouverture à la rencontre intercommunautaire. / According to a common opinion held in Western countries, the Instituted Sport would be a school of learning, sense of community, solidarity, sharing and rules of life; in short, it will socialize young people by integrating them into society. This research draws our attention to the forms of socialization that Lebanese society offers to “athletes”. If the act of thinking about sport first, as a non-political and, secondly, as a passion shared by all of the youth did not start today, this question reads differently in Lebanon, a country that has suffered from internal and regional conflicts for over 500 years. Politically and socially organized in ‘’community’’, Lebanon offer thereby a faith-based political model that permeates daily life, including the sports world. Each community is governed by a specific authority, ruled by its institutions and submitted to a court composed of independent members from the religious hierarchy, in which the state has recognized the jurisdiction to enforce its laws and customs. Tested in the field, the finding is yet to put into perspective. The survey reveals that the communal cleavages deeply affect the management bodies of sports federations and cause a religious breakdown in the management of committees. However, in sport as in other area of social life, the community is never “pure” and there are also inter-community coalitions in order to gain the sport’s power. Starting from a macro-sociological approach, the thesis propose to study the communal consolidation in the associative sport through two monographs club conducted in Beirut in order to analyze the sectarian dynamic: le Riyadi (Sporting club), a Muslim religious ruling, and for Christians, La Sagesse club. Sociological analysis shows two micro societies that practice sport in “between the self” format, but at the same time, have an opening at the inter-communal stage.
475

Emission d’auxine et de nitrates par les bactéries des turricules de vers de terre : effet sur la croissance et le développement des plantes / Emission of auxin and nitrate by bacteria in the earthworm's casts : effects on plants growth and development

Agapit, Corinne 25 May 2018 (has links)
Les plantes prélèvent des ressources dans leur environnement. Elles sont également exposées à de nombreux signaux, dont des molécules qui modifient profondément leur comportement et leur morphologie. La prédiction des flux de nutriments du sol vers la plante requiert une intégration de la régulation des flux par les signaux qui déterminent la cinétique des adaptations des plantes. Au cours de cette thèse, différentes approches expérimentales et analytiques (split-root, marquage isotopique, analyse racinaire) ont permis d’étudier le couplage signaux-flux dans les interactions entre plantes, microorganismes et vers de terre. Nous avons démontré dans un premier temps, que les vers de terre ont un effet systémique sur la croissance et le développement des plantes (Hordeum Vulgare L. et Oryza sativa L.) et que cet effet est dépendant de l’abondance des vers. Un travail méthodologique d’optimisation du dispositif split-root (séparation des racines d’une même plante entre deux compartiments) nous a permis d’améliorer la survie des plantes (Brachypodium distachyon L.) et leur émission de racines. Ce dispositif a été utilisé pour déterminer l’importance de la présence de turricules et de leur localisation spatiale sur le prélèvement d’azote par la plante. L’absence d’effet observé au cours de cette expérimentation nous a conduits à aborder les mécanismes pouvant survenir en présence de vers selon leur dimension temporelle. Nous avons ainsi démontré qu’une proportion importante de turricules entraîne une adaptation du système racinaire seulement lorsque la plante y est exposée pendant une durée suffisante. Ces résultats sont la première démonstration que la cinétique des différents mécanismes ayant lieu dans les turricules est déterminante pour expliquer l’effet positif des turricules sur la croissance des plantes / Plants take up resources in their environment. They are also exposed to many signals, including molecules that profoundly alter their behavior or morphology. The prediction of the flow of nutrients from the soil to the plant requires an integration of flux regulation by signals which determine the kinetics of plant adaptations. During this thesis, different experimental and analytical approaches (split-root, isotopic labeling, root analysis) allowed us to study the coupling between signals and flows in the interactions between plants, microorganisms and earthworms. We first demonstrated that earthworms have a systemic effect on the growth and development of plants (Hordeum Vulgare L. and Oryza sativa L.) and that this effect is dependent on the abundance of earthworms. A methodological study aiming at optimizing the split-root device (the sharing of roots of a single plant into two compartments) helped us to improve plant (Brachypodium distachyon L.) survival and their emission of roots. This experimental set up was used to determine the importance of the presence of casts and their spatial localization on the N uptake by the plant. The lack of effect observed during this experiment lead us to address the mechanisms that may occur in the presence of worms according to their temporal dynamics. We then demonstrated that an important proportion of casts was responsible for root system adaptation only when the plant was exposed to casts for a sufficient period of time. These results are the first demonstration that the kinetics of the different mechanisms occurring in casts is crucial to explain the positive effect of casts on plants growth
476

[en] DOMESTIC VIOLENCE AND GENERATIONAL PSYCHIC TRANSMISSION / [pt] VIOLÊNCIA CONJUGAL E TRANSMISSÃO PSÍQUICA GERACIONAL

HELENA PINHEIRO JUCA-VASCONCELOS 14 August 2018 (has links)
[pt] O presente trabalho buscou verificar as possíveis relações entre violência conjugal e transmissão psíquica geracional. Esse estudo é relevante pela alta prevalência da violência contra a mulher e por essa ser considerada problema de saúde pública. O objetivo principal deste trabalho foi investigar a possível transmissão da violência de uma geração à outra, identificando se houve a ocorrência da mesma também na família de origem e suas prováveis ressonâncias. Averiguou-se também que violências as vítimas sofreram e como as mesmas eram conceituadas por elas, assim como se buscou compreender como os abusos estavam presentes em suas vidas. Para alcançar os objetivos, realizou-se pesquisa de campo qualitativa, entrevistando nove mulheres vítimas de violência física de parceiros íntimos, através de entrevista por bate-papo na internet. O procedimento utilizado foi o Método de Explicitação do Discurso Subjacente (MEDS). Os resultados obtidos indicaram nítida repetição da violência entre os familiares, seja na posição de algoz, seja na de vítima. / [en] This study aims at evaluating the possible relationship between domestic violence and generational psychic transmission. It is relevant due to the high prevalence of violence against women, and because this is actually considered a public health problem. The main objective was to investigate the possible transmission of violence from one generation to another and its probable resonance. It examines what types of violence the victims suffered and how they conceptualized it. To achieve the objectives, a qualitative fieldwork was carried out interviewing nine women victims of physical violence by intimate partners through means of Internet chat conferences. The procedure used was the Underlying Discourse Unveiling Method (UDUM). The results indicate a clear repetition of violence among family members, from the standpoint of the perpetrator and of the victim.
477

Estágio supervisionado de Ciências Biológicas : aproximações entre o legal e o real /

Sposito, Neusa Elisa Carignato. January 2009 (has links)
Orientador: Ana Maria de Andrade Caldeira / Banca: Álvaro Lorencini Júnior / Banca: Nelson Antonio Pirola / Banca: Celi Rodrigues Chaves Dominguez / Banca: Renato Eugênio da Silva Diniz / Resumo: Este estudo trata do estágio supervisionado realizado por dezenove licenciandos do Curso de Licenciatura de Ciências Biológicas, da UNESP - Bauru, no segundo semestre de 2006 em três diferentes Escolas de Educação Básica, públicas. O objetivo da pesquis foi verificar se a efetivação do estágio supervisionado poderia ocorrer em atendimento às determinações das Diretrizes Curriculares Nacionais para a Formação de Professores (DCNs) no que se refere à parceria entre as instituições formadoras: a Universidade e a Escola de Educação Básica. Essa legislação propõe um acordo preliminar entre as diferentes instituiçõe de ensino e, em decorrência desse acordo, a elaboração de um projeto de estágio com ações de mútua colaboração entre elas. Há necessidade de se pesquisar sobre esse assunto, em especial na Licenciatura em Ciências Biológicas, diante do pouco que foi publicado até agora, em virtude de a lei estar em fase de implementação, por exemplo. A presente pesquisa teve três etapas: a preliminar (momento da apresentação da pesquisadora às duas diretoras e uma vice-diretora das três escolas de educação básica do estágio supervisionado propriamente dito, envolvendo os licenciandos, as professoras, os alunos das escolas públicas, as diretoras, vice-diretora e coordenador pedagógico) e a final (período de encerramento, com uma avaliação escrita feita pelos licenciados sobre o estágio realizado). Trata-se de pesquisa qualitativa que se assemelha ao estudo de caso e está fundamentada em uma das modalidades da investigação qualitativa apresentada por Flick (2004), que se refere à construção e à compreensão de textos a partir da experiência realizada, ou seja, da pesquisa. Os instrumentos de coleta de dados foram: gravações, relatórios, anotações, questionários. Além das DCNs, os autores que sustentam esse trabalho são:... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study treats about the supervised student teaching practiced by nineteen majoring students of the Major Biological Sciences Course of UNESP - Bauru, on the second semester of 2006 in three different Schools of Basic Education, public ones. The objective of the research was to verify if the effectuation of the supervised student teaching could occur according to the determinations of the National Curricular Directives for the Graduation of Teachers (DNCs) on what is referred to the partnership between graduating institutions: the University and the School of Basic Education. This legislation proposes a preliminary agreement between the different teaching institutions and, as result of this agreement, the elaboration of a student teaching project with cooperative actions between them. There is a research need about this subject, especially on Majoring on Biological Sciences, in front of what was published so far, in the fact of the law being under implementation, for example. The present research had three stages: the preliminary (moment of the introduction of the researcher to the two principals and one vice-principal of three schools of basic education with supervised student teaching centered on the partnership between institutions), intermediary (stage of carrying out the supervised student teaching, involving the majoring students, teachers, students of publi schools, principals, vice-principal and pedagogical counselor) and final (period of conclusion, with a writing evaluation made by the majoring students about the student teaching accomplished). It is a qualitative research similar to the case study and is based upon one of the forms of qualitative investigation presented by Flick (2004), which refers to the text construction and comprehension starting from the accomplished experience, which means, the research. The instruments of data collection were: records, reports... (Complete abstract click electronic access below) / Doutor
478

Escoriação psicogênica : aspectos psicológicos e fatores de personalidade /

Freitas, Débora Elisa Parente de. January 2011 (has links)
Orientador: Carmen Maria Bueno Neme / Banca: Heron Fernando de S. Gonzaga / Banca: Sandra Leal Calais / Resumo: A escoriação psicogênica tem sido abordada em estudos médicos que a associam a diversos transtornos ou doenças ou que buscam identificar a eficácia de diferentes tipos de tratamentos e medicamentos, além de outras questões afeitas à área. Embora a literatura a relacione a fatores afetivo-emocionais, há escassez de pesquisas no campo da psicologia sobre esta psicodermatose. A Escoriação Psicogênica é mais comumente encontrada em mulheres que, ao agredirem a própria pele, causam uma perceptível desifiguração provocada pelas lesões. A literatura, sistematicamente revisada neste trabalho, aponta fatores desencadeantes como a dificuldade em lidar com os próprios impulsos e a compulsão, pois o paciente admite ser o causador das lesões, porém, de maneira involuntária. A pele, o maior órgão do corpo humano, tem a mesma origem embrionária que o sistema nervoso e é frequentemente associada a processos psicológicos. Quando lesionada, leva a sofrimento emocional e a afastamento afetivo e social. o presente estudo abordou os aspectos psicológicos e fatores de personalidade associados à escoriação psicogênica a partir de relatos de pacientes em processo de diagnóstico e/ou tratamento dermatológico do Instituto Lauro Souza Lima - Bauru e de resultados do IFP - Inventário Fatorial de Personalidade, aplicado em dois grupos de mulheres: 20 com e 20 sem escoriação psicogênica, sendo este útlimo, composto por trabalhadoras da prefeitura municipal da cidade do interior paulista. Este estudo investigou a história de vida, os aspectos psicológicos e os fatores de personalidade possivelmente relacionados à escoriação psicogênica em vinte mulheres com esse diagnóstico, comparando-se os resultados obtidos no IFP com os de mulheres sem a psicodermatose. Foi realizada entrevista de anamnese com as mulheres com escoriação psicogênica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Psychogenic excoriation has been approached on medical studies, which both associate it to several disorders or diseases or try to identify the efficacy of distintic treatment methods, besides other themes on such area. Even though the specific literature includes it on affetive-emotional reasons, there is a lack of researchers on Psychology field on this psychodermatosis. Psychogenic excoriation is a disorder mos commonly found on women who picks - scratches - their own skin, causing them a noticeable disfiguration due to the wounds. Literature on the subject has been systematically referred to in order to produce this paper. It points out reasons such as difficulty to deal with one's own impulses and compulsion, since the patient admits being the one who causes the wounds in an involuntary manner, though. The skin, largest organ of the human body, has the same Embryo origin of the nervous system and is frequently associated to psychological processes. The wounded skin causes suffering and affective / social seclusion. In this study, the psychological aspects and the personality treat associated to psychogenic excoriation have been studied. The data has been collected from reports of patients during dermatological diagnosis or treatment on 'Instituto Lauro Souza Lima, in Bauru, and from results of a test called IFP (Inventário Fatorial de Personalidade or Personality Factorial Inventory), applied on two groups of women: the first one having twenty women suffering from psychogenic excoriation and the second one having healthy women (groups A and B). The latter has been composed from civil servers in a small town. In order to prepare this study, the psychological aspects and the personality treat possibly related to psychogenic excoriation in twenty women having such diagnosis, comparing them with the results of the Personality Factorial Inventory of the healthy... (Complete abstract click electronic access below) / Mestre
479

Vivre dans le non-loti de Ouagadougou : processus de marchandages fonciers entre citadins, chefs traditionnels et autorités publiques / Living in the non-plotted of Ouagadougou : process of land bargaining of city dwellers, traditional authorities and public authorities

Guigma, Pougdwendé Léandre 04 December 2017 (has links)
Cette recherche interroge les interférences entre les pratiques des citadins et les politiques publiques dans l’aménagement et la gestion urbaine des quartiers non-lotis de Ouagadougou. La thèse principale est que les citadins interagissent avec les pouvoirs publics par leurs actions urbaines respectives. Les citadins déclenchent et/ou marchandent leurs actions dans le non-loti, au gré des décisions et des opérations publiques antérieures, présentes et projetées. La démonstration s’est effectuée suivant trois entrées. Dans un premier temps, l'analyse a porté sur les relations entre les espaces produits par les pratiques des citadins et ceux revendiqués par des pouvoirs publics. Puis les investigations se sont focalisées sur les images de ville mobilisées par les acteurs urbains, pour légitimer et motiver leurs actions. Enfin, l’analyse des effets réciproques des « politiques institutionnelles » sur les « dynamiques locales » (F. Navez Bouchanine, 2012) a mis en évidence les « compétences des citadins » (I. Berry-Chikhaoui, A. Deboulet 2000). Les terrains de recherche ont été trois quartiers non-lotis de Ouagadougou (Bissighin, Watinoma/Noghin/Basnéré et Tengandogo), où un regard réflexif a été porté sur les effets des actions urbaines prévues dans le cadre du Programme participatif d'amélioration des bidonvilles de ONU Habitat. L'analyse de la constitution et de la transformation de ces trois quartiers non-lotis a révélé des stratégies communes d'appropriations et de marchandages fonciers par les citadins et les pouvoirs publics, avec l'intermédiation des chefs traditionnels ou « cheffocratie » (A. Ouédraogo, 2014) et des organisations de la société civile. / This research questions the interference between the practices of urban dwellers and public policies in the urban planning and management of the non-plotted neighborhoods of Ouagadougou. The main thesis is that urban dwellers interact with public authorities through their respective urban actions. City dwellers trigger and / or bargain their actions in the non-plotted areas in the light of past, present and projected public decisions and operations. The demonstration was carried out following three inputs. Initially, the analysis focused on the relationships between the spaces produced by the practices of city dwellers and those claimed by public authorities. Then the investigations focused on city images mobilized by urban actors to legitimate and motivate their actions. Finally, the analysis of the reciprocal effects of "institutional policies" on "local dynamics" (F. Navez Bouchanine, 2012) highlighted the "skills of urban dwellers" (Berry-Chikhaoui, A. Deboulet 2000). The research fields were three non-plotted neighborhoods in Ouagadougou (Bissghin, Watinoma/Noghin/Basnéré et Tengandogo), where a reflexive look has been taken at the effects of the urban actions planned under the Participatory Slum Upgrading Program of UN Habitat. The analysis of the constitution and transformation of these three non-plotted neighborhoods revealed common strategies of appropriations and bargaining by urban residents and public authorities with the intermediation of traditional chiefs or " cheffocracy "(A. Ouédraogo, 2014) and civil society organizations.
480

Probability on the spaces of curves and the associated metric spaces via information geometry; radar applications / Probabilités sur les espaces de chemins et dans les espaces métriques associés via la géométrie de l’information ; applications radar

Le Brigant, Alice 04 July 2017 (has links)
Nous nous intéressons à la comparaison de formes de courbes lisses prenant leurs valeurs dans une variété riemannienne M. Dans ce but, nous introduisons une métrique riemannienne invariante par reparamétrisations sur la variété de dimension infinie des immersions lisses dans M. L’équation géodésique est donnée et les géodésiques entre deux courbes sont construites par tir géodésique. La structure quotient induite par l’action du groupe des reparamétrisations sur l’espace des courbes est étudiée. À l’aide d’une décomposition canonique d’un chemin dans un fibré principal, nous proposons un algorithme qui construit la géodésique horizontale entre deux courbes et qui fournit un matching optimal. Dans un deuxième temps, nous introduisons une discrétisation de notre modèle qui est elle-même une structure riemannienne sur la variété de dimension finie Mn+1 des "courbes discrètes" définies par n + 1 points, où M est de courbure sectionnelle constante. Nous montrons la convergence du modèle discret vers le modèle continu, et nous étudions la géométrie induite. Des résultats de simulations dans la sphère, le plan et le demi-plan hyperbolique sont donnés. Enfin, nous donnons le contexte mathématique nécessaire à l’application de l’étude de formes dans une variété au traitement statistique du signal radar, où des signaux radars localement stationnaires sont représentés par des courbes dans le polydisque de Poincaré via la géométrie de l’information. / We are concerned with the comparison of the shapes of open smooth curves that take their values in a Riemannian manifold M. To this end, we introduce a reparameterization invariant Riemannian metric on the infinite-dimensional manifold of these curves, modeled by smooth immersions in M. We derive the geodesic equation and solve the boundary value problem using geodesic shooting. The quotient structure induced by the action of the reparametrization group on the space of curves is studied. Using a canonical decomposition of a path in a principal bundle, we propose an algorithm that computes the horizontal geodesic between two curves and yields an optimal matching. In a second step, restricting to base manifolds of constant sectional curvature, we introduce a detailed discretization of the Riemannian structure on the space of smooth curves, which is itself a Riemannian metric on the finite-dimensional manifold Mn+1 of "discrete curves" given by n + 1 points. We show the convergence of the discrete model to the continuous model, and study the induced geometry. We show results of simulations in the sphere, the plane, and the hyperbolic halfplane. Finally, we give the necessary framework to apply shape analysis of manifold-valued curves to radar signal processing, where locally stationary radar signals are represented by curves in the Poincaré polydisk using information geometry.

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