In recent years, there has been a significant increase in the interest for snake like modular robots due to their superior locomotion capabilities in terms of versatility, adaptability and scalability. Passive wheeled planar snake like robots are a major category and they are being actively researched. Due to the nonholonomic constraints imposed on them, certain configurations lead to the singularity which must be avoided at all costs. Furthermore, it is vital to generate a locomotion pattern such that they can track a wide range of trajectories. All of these objectives must be accomplished smoothly and in an energy efficient manner. Studies indicate that meeting all of these requirements is a challenging problem. In this study, a novel form of the serpenoid curve is proposed in order to make the robot track arbitrary paths. A controller has been designed using the feedback linearization method. Afterwards, a new performance measure, considering both the efficiency and sustainability of the locomotion, has been proposed to evaluate the locomotion. Optimal parameters for the proposed serpenoid curve and the linear controller have been determined for efficient locomotion by running series of simulations. Relations between the locomotion performance, locomotion speed and eigenvalues of the linear controller have been demonstrated. Simulation results show striking differences between the locomotion by using the proposed serpenoid curve with optimal parameters and the locomotion by purely tracking a given path. Obtained results also indicate that the aforementioned requirements are met successfully and confirm the validity and consistency of the proposed performance measure.

Στην παρούσα διπλωματική εργασία μελετάμε την κλασική δυναμική ατόμου υδρογόνου σε γενικευμένο δυναμικό Van der Waals. Το πρόβλημα ανήκει στην ευρύτερη κατηγορία των μη γραμμικών Χαμιλτώνιων δυναμικών συστημάτων. Σκοπός της μελέτης είναι η ανάλυση των ιδιομορφιών της κανονικής και χαοτικής κίνησης του συστήματος στο μιγαδικό πεδίο του χρόνου και η εξαγωγή συμπερασμάτων σχετικά με την ολοκληρωσιμότητα και επιλυσιμότητά του. Εκείνο που θέλουμε να κατανοήσουμε, επίσης, είναι τον ρόλο που παίζει η εμφάνιση ιδιομορφιών σε κάποια σημεία του χώρου των φάσεων και κατά πόσο μπορούν αυτές να επηρεάσουν συνολικά τις ιδιότητες των λύσεων. Για πρώτη φορά, επίσης, στην διπλωματική αυτή εργασία εφαρμόζεται σε ένα Χαμιλτώνιο δυναμικό σύστημα μία νέα αριθμητική μέθοδος διάκρισης μεταξύ κανονικής και χαοτικής συμπεριφοράς σε διαφορετικές περιοχές του χώρου φάσεων, η μέθοδος των Μικρότερων Δεικτών Ευθυγράμμισης (Smaller Alignment Indices method ή SALI). Η μέθοδος αυτή έχει χρησιμοποιηθεί κατά το πρόσφατο παρελθόν σε απεικονίσεις δύο, τεσσάρων και έξι διαστάσεων με πολύ ενδιαφέροντα αποτελέσματα. Χαρακτηριστικά της είναι η αποτελεσματικότητα και η δυνατότητα εξαγωγής χρήσιμων συμπερασμάτων ως προς την κανονική και χαοτική φύση των τροχιών ενός δυναμικού συστήματος με μεγαλύτερη ταχύτητα και αξιοπιστία από την μέθοδο των χαρακτηριστικών εκθετών Lyapunov καθώς και άλλων νεότερων μεθόδων στην σύγχρονη βιβλιογραφία. Εδώ θα παρουσιασθεί η μέθοδος αυτή με ορισμένες βελτιώσεις ώστε να μπορεί να εφαρμοσθεί σε συστήματα μη γραμμικών διαφορικών εξισώσεων οποιασδήποτε διάστασης ελέγχοντας συστηματικά ένα όσο πυκνό πλέγμα αρχικών συνθηκών του χώρου φάσεων επιθυμούμε, αντιστοιχώντας σε κάθε μία από αυτές ένα χρώμα. Κάθε χρώμα αντιστοιχεί και σε ένα διαφορετικό εύρος τάξεων του SALI δημιουργώντας έτσι μία συνολική εικόνα στο χώρο φάσεων που μας επιτρέπει να γνωρίζουμε τη φύση της τροχιάς κάθε συγκεκριμένης αρχικής συνθήκης. Σχηματίζεται με αυτόν τον τρόπο το "μωσαϊκό" του χώρου φάσεων και αποκαλύπτονται περιοχές κανονικής κίνησης, χαοτικής κίνησης καθώς και νησίδες ή περιοχές στις οποίες δεν αντιστοιχεί καθόλου κίνηση. / In this master thesis we study the classical dynamics of hydrogen atoms in a generalized Van der Waals potential. The problem belongs to the class of non linear Hamiltonian systems. Our aim is the singularity analysis of the ordered and chaotic motion of the system in the complex plain of time and the extraction of valuable conclusions concerning its integrability and solvability. What we want to understand, also, is the role of the emergence of singularities in some points of the phase space of the aforementioned system and how the singularities can affect globally the properties of the solutions. For the first time, in this master thesis, we introduce and apply in a Hamiltonian system a new numerical method for the fast and efficient discrimination between ordered and chaotic motion in different parts of phase space, namely the method of the Smaller Alignment Index (SALI). The method has been introduced and applied recently in mappings of two, four and six dimensions with very satisfactory results. Its main characteristics are the effectiveness and the ability of extracting valuable conclusions about the ordered and chaotic nature of trajectories of a dynamical system faster than the traditional method of Lyapunov exponents as well as of other indices in the bibliography. We will introduce SALI with appropriate modifications that help using it in non linear systems of differential equations of arbitrary dimensions checking systematically a dense grid of initial conditions and corresponding in every orbit a different color. Every color corresponds to a different range of SALI values creating by that way a global picture of the phase space that allows us to know the dynamic nature of initial conditions. By that way, we construct a “mosaic” of the phase space and reveal parts of ordered motion as well as parts of chaotic motion and islands of stability.

En se penchant sur L’homme révolté d’Albert Camus, ce mémoire entend évaluer la pertinence de la révolte camusienne à l’aube du troisième millénaire. Du constat de l’absurde quant à la condition existentielle de l’homme, Camus a esquissé une révolte affranchie de toute idéologie en démontant, entre autres, les mécanismes propres à la philosophie de l’histoire et au nihilisme. À partir de la critique des pensées hégélienne, nietzschéenne et marxienne, il a tenté de définir les caractéristiques inhérentes à la révolte. Rédigé au milieu du XXe siècle, L’homme révolté est marqué par les séquelles d’une histoire chaotique déjà plus que cinquantenaire. Pour autant, son propos semble être encore d’actualité. Avec la complicité de philosophes contemporains tels que Cornélius Castoriadis, Pierre Rosanvallon et Bernard Stiegler, c’est autant la pertinence de la révolte camusienne qui est ici considérée qu’une corrélation entre cette révolte et la dignité humaine. L’homme révolté a-t-il encore sa place en ce début du troisième millénaire et dans l’affirmative : quelle est cette place? / By examining Albert Camus’ L’homme révolté (The Rebel), this dissertation intends to assess the relevance of Camusian revolt at the dawn of the third millennium. From an acknowledgement of the absurd as regards the existential condition of man, Camus outlined a revolt free of any ideology by demonstrating, for example, the mechanisms innate to the philosophy of history and nihilism. Starting with a critique of Hegelian, Nietzschean and Marxist thought, he attempted to define the characteristics inherent to rebellion. Written in the mid-20th century, L’homme révolté is marked by the aftermath of chaos and destruction of that era, yet now more than five decades on, his words appear to remain relevant today. With the complicity of contemporary philosophers such as Cornélius Castoriadis, Pierre Rosanvallon and Bernard Stiegler, this paper will focus not only on the pertinence of Camusian rebellion, but also on a correlation between revolt and human dignity. Does L’homme révolté still have his place as the third millennium begins and, if so, what is that place?

In this thesis, we introduce a new approach to wavefront phase reconstruction in Adaptive Optics (AO) from the low-resolution gradient measurements provided by a wavefront sensor, using a non-linear approach derived from the Microcanonical Multiscale Formalism (MMF). MMF comes from established concepts in statistical physics, it is naturally suited to the study of multiscale properties of complex natural signals, mainly due to the precise numerical estimate of geometrically localized critical exponents, called the singularity exponents. These exponents quantify the degree of predictability, locally, at each point of the signal domain, and they provide information on the dynamics of the associated system. We show that multiresolution analysis carried out on the singularity exponents of a high-resolution turbulent phase (obtained by model or from data) allows a propagation along the scales of the gradients in low-resolution (obtained from the wavefront sensor), to a higher resolution. We compare our results with those obtained by linear approaches, which allows us to offer an innovative approach to wavefront phase reconstruction in Adaptive Optics.

Made available in DSpace on 2014-06-11T19:23:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-12-22Bitstream added on 2014-06-13T20:47:56Z : No. of bitstreams: 1 sousa_kca_me_mar.pdf: 564771 bytes, checksum: 71d2abc323fd55dbe3a26dfd3eaf74a1 (MD5) / O objetivo deste trabalho é compreender a contribuição de Jean Jacques Rousseau na construção do pensamento sobre as diferenças entre os homens e que no século seguinte se constituiu enquanto disciplina acadêmica de antropologia e de que forma ela ocorreu. Suas obras mais significativas foram utilizadas, contextualizando-se as idéias dentro do momento histórico em que se desenvolveram na Europa dos séculos XVIII e XIX. Os conceitos de cultura/natureza, identidade/diversidade e singularidade/universalidade foram enfatizados numa tentativa de se entender o pensamento social europeu diante da diversidade de culturas existentes no planeta e cujo início de mapeamento teve início com o colonialismo ocidental. / The goal of this work is comprehend Jean Jacques Rousseau’s contribution on the construction of thoughts about differences between men and which on next century constituted as academic discipline of anthropology and in which way it occurs. His most significant works were used, contextualizing the ideas within historical moment at which they developed in Europe XVIII and XIX centuries. The concepts of culture/nature, identity/diversity and singularity/universality were emphasized for trying to understanding the European social thought before diversity of cultures existing in the planet and which maping had beginning with the occidental colonialism. Keywords: Nature/Culture. Identity/Diversity. Singularity/universality. Rousseau. History of classical anthropological thought. Evolution and progress.

Vad vi framför är ett alternativ till idealismen och vi bemöter det ideella med relationell ontologi. Vi jämför Peter van Inwagen (2011), Bryan E. Bannon (2011), Achille Varzi (2016), Gil C. Santos (2015) och Robin Durie (2002) för att skapa en förståelse för vad relationell ontologi innebär. Vidare väljer vi att använda Andrew Benjamins (2015) definition för vidare struktur av vår teoretiska metod. Denna konkretisering menar på att vår tillblivelse är skapad utifrån relationer, ett utbyte mellan singulariteter, de punkterna som definierar en artefakt eller ett fenomen. Vidare analyserar vi analog skissteknik och applicerar den analysen och dess beståndsdelar på digitala tekniker som bildredigering och 3D modellering i vad vi kallar den Rhizo – Singulär analys som process metoden. Vad vi får ut är ett alternativt sätt att skapa vilket vi väljer att definiera som relationell avbildning, med detta utmanar vi idealismen och de ideella mönsterbilderna (Ohlsson, 2013). Med andra ord att vi förhåller oss till en öppenhet och de förvrängningar inom sinnes – världen utifrån Aristoteles och estetiken enligt Danius, Sjöholm, & Wallenstein (2012). Vi diskuterar de val som vi gör i designprocessen och fortsätter att argumentera för öppna förhållningssätt och förståelse som vi hämtar och jämför från Benjamin (2015) och Deleuze & Guattaris (1987) rhizomen. Undersökningen och den metoden vi skapar kan bli förstådd samt tillämpad i flertalet variationer. Slutgiltligen att den teoretiska metoden växer och förändras utav personer i en plural händelse vilket är Rhizo - Singulär analys som processmetoden. / We present an alternative to idealism and we meet the ideal with the concept of relational ontology. We compare Peter van Inwagen (2011), Bryan E. Bannon (2011), Achille Varzi (2016), Gil C. Santos (2015) and Robin Durie (2002) to create an understanding for what relational ontology is or could be. We choose Andrew Benjamin's (2015) definition to structure our theoretical method. This concretization means relations are fundamental for our becoming as people and objects. Relations are an exchange between singularities, the points which define an artefact or a phenomenon. Continually we analyze sketching techniques and apply that analysis and its components on digital techniques as photo editing and 3D modeling in what we call the Rhizo – Singular analysis as a process method. What we get from doing this is an alternative way of creating which we choose to define as a relational imaging, with this we challenge the idealism and the ideal pattern images (Ohlsson, 2013). In other words we approach to a openness and the material worlds distortions from Aristoteles and the aesthetics of Danius, Sjöholm, & Wallenstein (2012). We discuss the choices that we have made in the design process. We continue to argue for the open approach, the understanding which we gain and compare from Benjamin (2015) as well as Deleuze & Guattari’s (1987) rhizome. In other words the research, it's methods themselves can be understood and be applied in several variations. Finally the theoretical method grows and changes by people in a plural event that is Rhizo - Singular analysis as a process method.

A dissertação tem por objetivo observar as sutilezas intrínsecas ao método narrativo de Machado de Assis em Dom Casmurro e alguns contos. Analisaremos o aspecto relacional entre homens e mulheres e a problemática articulação entre casamento, amor e adultério. Daremos ênfase à singularidade feminina diante das injunções de um universo masculino. / The purpose of this essay is to perceive the intrinsical subtileness to Machado de Assis´ narrative method in Dom Casmurro and some short stories. We will analyse the relational aspect between men and women and the questionable link among marriage,love and adultery. We will emphasize the female singularity in what refers to facing impositions of a male universe.

Este trabalho de pesquisa tem como objetivo colocar em análise a relação entre sujeito e laço social nas situações de sofrimento psíquico relacionadas à exposição do sujeito a violências sociais. Propomos pensar sobre a função e o lugar da escuta do sofrimento psíquico na política pública de assistência social, considerando o modo de organização desta política pública através do Sistema Único de Assistência Social (SUAS), buscando articular a dimensão subjetiva e singular dos sujeitos com a dimensão política e social. Estas interrogações se produziram em um espaço de acompanhamento, em um Centro de Referência Especializado de Assistência Social (CREAS), de famílias moradoras da Vila Chocolatão, em Porto Alegre, que foram reassentadas em outro ponto da cidade. Seus moradores mais antigos viviam há 24 anos neste local e, em sua maioria, trabalham essencialmente na catação e separação de lixo, sendo que muitos possuem, em suas trajetórias, histórias de vida na rua, além de ser uma comunidade em constante movimento na forma de habitar. A Vila Chocolatão e o coletivo de moradores que acompanhamos se apresentaram como um ponto de partida de uma construção que se deu aos poucos, incluindo as imprecisões, os estranhamentos e as interrogações para a composição de narrativas que nos serviram de guia no trabalho de escuta. Como um ponto de origem, a Vila Chocolatão – através de seus traços – foi dando lugar aos sujeitos de nossa pesquisa. Este estudo parte do pressuposto construído por Freud no texto “O Mal-Estar na Cultura” (1930 [2010]), de que vivemos sob diversas formas do mal-estar que nos trazem à tona a dimensão faltosa e de infelicidade de viver na coletividade, principalmente em decorrência das relações sociais. Frente ao reconhecimento da impossibilidade da supressão do mal-estar buscamos, nesse trabalho, situar, através da ética psicanalítica, um posicionamento que não esteja pautado pela sua eliminação, mas pela compreensão da heterogeneidade radical do inconsciente, a qual não é possível dominar e sim singularizar. Nesta direção, nos interessa interrogar as modalidades do laço que presentificam a exclusão social de maneira articulada aos significantes construídos em um dado momento da cultura. E, a partir desse exame, desenhar uma intervenção clínica na política pública de assistência social que leve em consideração o sujeito em sua singularidade, considerando as questões que emergem da clínica a respeito do trauma, do luto e das expressões da dor. Nesse sentido, apostamos na potência da narratividade em singularizar e dar voz ao testemunho dessa experiência Neste trabalho, intentamos indicar o quanto a “exclusão” contrasta com a prática da transferência, que implica a suposição do sujeito em presença e propusemos discutir que perspectivas se lançam na clínica ao operarmos com o significante “exclusão” na referência ao singular do sujeito e não com seu correlato “inclusão”. Tal deslocamento de perspectiva poderia afetar a intervenção que se pauta por um ideal de universalidade de cidadania, movendo-a em direção à abertura de uma escuta do sujeito que preserve a indissociabilidade entre clínica e política. / This research aims to put in question the relationship between subject and social ties in situations of psychological distress related to exposure of the subject to social violence. We propose to think about the role and place of hearing of psychological distress in the public policy of social assistance, considering the mode of organization of public policy through the Social Assistance System (SAS), seeking to articulate the subjective and unique to the size of the subject political and social. These questions were produced in a space monitoring in a Reference Center for Specialized Social Assistance (RCSSA) of families living in the Village Chocolatão, in Porto Alegre, who were resettled in another part of town. His older residents living in this place 24 years ago and, mostly, working mainly in grooming and separation of garbage, and many have in their history, stories of street life, besides being a community in constant motion in the form of dwell. The Village Chocolatão and the collective residents follow is presented as a starting point of a building that took place gradually, including the inaccuracies, the surprise and the questions for the composition of narratives that have served us as guide for the work of listening. As a point of origin, the Village Chocolatão – through their traces – was giving way to the subjects of our research. This study assumes constructed by Freud in the text “The Malaise in the Culture” (1930 [2010]), that we live under various forms of malaise that we bring up the scale fault and misfortune to live in the community mainly as a result of social relations. Faced with the recognition of the impossibility of removing the uneasiness we seek in this work place, through the psychoanalytic ethics, a position that is not guided by its elimination, but by understanding the radical heterogeneity of the unconscious, which is not possible to master, but singled. In this direction, we are interested in interrogating the terms of the bond that make this social exclusion in coordination with significant built in a given time of culture. And from this review, design a clinical intervention in the public policy of social assistance that takes into account the subject in its uniqueness, considering the issues that emerge from the clinic on trauma, mourning and the expression of pain. Accordingly, we rely on the power of narrative in single out and give voice to the testimony of this experience this work, intend to indicate how much the “exclusion” contrasts with the practice of transfer, which involves the assumption of the subject in the presence and proposed to cast discuss what prospects the clinic to operate with significant "exclusion" in reference to the singular subject and not with its correlate “inclusion”. This shift in perspective could affect the intervention that is guided by an ideal of universal citizenship, moving it toward the opening of a guy who listens to preserve the inseparability between practice and policy.

Esse estudo refere-se às possibilidades de interlocução entre Psicanálise, Educação e Educação Especial. Pretende destacar, sobretudo, como as referidas áreas do conhecimento humano podem beneficiar-se de um trabalho interdisciplinar. O objetivo principal dessa pesquisa foi investigar a prática de docentes de uma escola especial, verificando como se sentem no efetivo exercício de sua função e de que forma a interlocução com a psicanálise pode possibilitar uma prática ainda mais qualificada. Para tal ancorei esse estudo na teoria freudo-lacaniana e suas articulações com a neurologia, permeada, por outras linhas teóricas de psicanálise e de educação, buscando um diálogo interdisciplinar entre elas. O percurso metodológico foi desenvolvido em uma abordagem qualitativa, vista sua abrangência e amplitude, com base na análise de conteúdo. As estratégias utilizadas para a obtenção dos dados foram entrevistas, observações e coleta de documentos. Esse estudo permitiu verificar a relevância das contribuições da psicanálise para a educação especial, bem como para o campo da educação e a possibilidade de triangular esse eixo. / This study refers to the possibilities of interlocution among Psychoanalysis, Education Studies and Education for Special needs people. It intends to point out, above all, how these related areas of the human knowledge can be benefitted by an interchanging work. The main purpose of this research was to investigate the teaching staff practice from a school for special needs pupils, checking how they feel in their job activities and how the use of psychoanalysis can enable them to a more qualifying practice. For that, I supported this study in the freudo-lacanian theory and its articulations with neurology, interposing other theoretical currents of psychoanalysis and education, methodological looking for an interchanging relation between them. The methodical course was developed in a qualified approach for its greatness and amplitude, based on the content analysis. The used strategies for the data’s acquirement were interviews, observations and collect of some documents. The present study allowed us to check the relevant contributions of psychoanalysis for special needs people education as well as for the field of education in general and the possibility of interchanging among these three areas.

V klasické fyzice m·že být ustavena statická rovnováha v soustavě, která obsahuje extrémně nabité zdroje gravitačního a elektromagnetického pole. Udivujícím faktem je, že tato situace m·že nastat i pro černé díry v relativis- tické fyzice. Tato práce vyšetřuje speciální případ nekonečně dlouhé, extrémně nabité struny, zkoumá geometrii prostoročasu, elektrogeodetiky, vlastnosti zdroje a srovnává řešení se situací v klasické fyzice. Dále se zabýváme analogickou situací v dynamickém prostoročase s kosmologickou konstantou, a řešení porovnáváme s jeho statickou verzí. Nakonec zkoumáme periodické řešení Laplaceovy rovnice, které odpovídá nekonečně mnoha extremálním bodovým zdroj·m rozloženým v pravidelném rozestupu podél přímky. Vyšetřujeme vlastnosti elektrostatického potenciálu a ukazujeme, že v limitě velké vzdálenosti od osy tvořené zdroji pře- chází toto řešení v nabitou strunu. 1