Dissertations / Theses on the topic 'Space and time (Representations)'
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BETTENCOURT, THOMAZ ESTRELLA DE. "TIME AND SPACE TO KANT: THE TIME AND SPACE REPRESENTATIONS IN THE CONTEXT OF KANT`S CRITICAL SYSTEM." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2008. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=12336@1.
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FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIROO objetivo desta dissertação é examinar o papel desempenhado pelas representações do tempo e do espaço no sistema crítico kantiano. Mas, diversas questões surgem a partir desta pesquisa e se nos incumbimos de respeitar o legado de Kant e o seu espírito metodológico não devemos negligenciá-las. Assim, com o intuito de lançar luz sobre um tema tão obscuro, o presente trabalho aceita o desafio, e o estabelece como ponto de partida, de expor os conceitos de tempo e de espaço por uma análise histórica. E sobre o terreno seguro da tradição filosófica podemos descansar e recobrar forças para continuar a seguir os passos de Kant e encontrar as origens da Estética Transcendental. Portanto, o centro desta investigação é determinar de forma precisa o sentido das representações do tempo e do espaço a suas implicações para a teoria do conhecimento de Kant. Finalmente, ao término desta tumultuada jornada teremos alcançado uma melhor compreensão sobre a relação das intuições do tempo e do espaço com a coisa em si mesma, e, a sua importância para o idealismo transcendental.
The task of this dissertation is to examine the role played by the time and space representations in Kant`s critical system. But, several questions emerge from this inquiry, and if we are to respect Kant`s legacy and his methodological spirit we shall not neglect them. Then, as an effort to shed light over such an obscure matter the present work accepts the challenge, and establishes it as a starting point, of expounding time and space concepts through a historical analysis. And on the solid grounds of the philosophical tradition we can rest and regain strength to continue following Kant`s steps and finding the origins of the Transcendental Aesthetics. Therefore, the core of this investigation is determining accurately the meaning of time and space representations and its implications to Kant`s theory of knowledge. Finally, at the end of this troubled journey we will have reached a better understanding of the relationship between the time and space intuitions and the thing-in-itself and its significance to the transcendental idealism.
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Thathachar, Jayram S. "Time-space tradeoffs and functional representations via branching programs and their generalizations /." Thesis, Connect to this title online; UW restricted, 1998. http://hdl.handle.net/1773/6951.
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Trimm, Alexandra. "The Frozen Moment: Representations of Space, Time and the Experiential in Installation Art." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/scripps_theses/313.
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This paper examines the history of installation art and explains the concept and themes within my installation component of the studio art major. It details how readymades, site-specificity, and an emphasis on experiential work all contributed to the creation of installation art as a medium. Next, I turn to my own work, exploring the theme of representing time and altering the perceptions of the viewer. Through a web of fishing line and tempered glass, the installation visually imitates a single, frozen moment of an explosion that the viewer can walk into and explore. The paper continues with a discussion of relevant themes in the work by contemporary artists Ori Gerst, Heide Fasnacht, Cornelia Parker, E.V. Day, Lee Bontecou, and James Turrell, and concludes with ideas for the continuation of the project in the spring 2014 semester.
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Zhang, Qiu Jun. "How Chinese - English Bilinguals Think About Time : The Effects of Language on Space-Time Mappings." Thesis, Stockholms universitet, Centrum för tvåspråkighetsforskning, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-184684.
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The last decades have witnessed the resurgence of research on linguistic relativity, which provides empirical evidence of possible language effects on thought across various perceptual domains. This study investigated the linguistic relativity hypothesis in the abstract domain of time by looking at how L1 Chinese - L2 English bilinguals conceptualize time in two-dimensional space. English primarily relies on horizontal spatial items to talk about time (e.g., back to youth); in addition to horizontal spatial metaphors (e.g., ‘front year’), Chinese speakers also commonly use vertical metaphors to describe time (e.g., ‘up week’). If language has an effect on thought, then spatial-temporal metaphors should shape people’s temporal cognition. In this study, we examined whether spatial-temporal metaphors impact online processing of time and long-term habitual thinking about time. Experiment 1 showed that bilinguals could automatically access the timeline which corresponded to the immediate linguistic context. In Experiment 2, a majority of bilinguals demonstrated salient vertical bias for temporal reasoning, whereas a small number of participants relied on the horizontal axis to represent time. The dominant thinking patterns for time documented here (65% prefer a vertical representation of time; 35% horizontal) run counter to the fact that horizontal metaphors are twice as common in Chinese as vertical metaphors. Further, it was found that bilinguals who used English more frequently were more likely to have a less vertical bias, which suggested a role of L2 experience in conceptual representations. Taken together, the evidence in this study showed that spatial-temporal metaphors have both short-term and long-term effects on mental representations of time, but also that space-time mappings do not depend solely on linguistic factors.
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Ghosh, Sourav. "Thermodynamics of Margulis Space Time." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112137/document.
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Dans ma thèse, je décris les feuilles stables et instables pour le flot géodésique sur l’espace des géodésiques non-errant de type espace d’un espace-temps de Margulis et je démontre des propriétés de contraction des feuilles sous le flot. Je montre aussi que la monodromie d’un espace-temps de Margulis est une représentation Anosov dans un groupe de Lie non semisimple. En outre, je montre que les applications limites et reparamétrisation varient analytiquement. Enfin, à l’aide de la propriété métrique Anosov, nous définissons la métrique de pression sur l’espace modulaire des espaces-temps de Margulis sans pointes et je démontre qu’elle est définie positive sur les sections d’entropie constanteIn my thesis I describe the stable and unstable leaves for the geodesic flow on the space of non-wandering spacelike geodesics of a Margulis Space Time and prove contraction properties of the leaves under the flow. I also show that monodromy of Margulis Space Times are “Anosov representations in non semi-simple Lie groups”. Moreover, I show that the limit maps and reparametrizations vary analytically. Finally using the metric Ansosov property we define the Pressure metric on the Moduli Space of Margulis Space Times without “cusps” and show that it is positive definite on the constant entropy sections
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Milicic, Maja. "Action, Time and Space in Description Logics." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2008. http://nbn-resolving.de/urn:nbn:de:bsz:14-ds-1220871815669-38852.
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Description Logics (DLs) are a family of logic-based knowledge representation (KR) formalisms designed to represent and reason about static conceptual knowledge in a semantically well-understood way. On the other hand, standard action formalisms are KR formalisms based on classical logic designed to model and reason about dynamic systems. The largest part of the present work is dedicated to integrating DLs with action formalisms, with the main goal of obtaining decidable action formalisms with an expressiveness significantly beyond propositional. To this end, we offer DL-tailored solutions to the frame and ramification problem. One of the main technical results is that standard reasoning problems about actions (executability and projection), as well as the plan existence problem are decidable if one restricts the logic for describing action pre- and post-conditions and the state of the world to decidable Description Logics. A smaller part of the work is related to decidable extensions of Description Logics with concrete datatypes, most importantly with those allowing to refer to the notions of space and time.
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Padilla, Margara Tejera. "Space-time representation and editing of 3D video mesh sequences." Thesis, University of Surrey, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.616956.
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Advances in surface performance capture have enabled the reconstruction of real world scenes such as people and animals with a realism hard to achieve by an animator. The work presented in this thesis aims to develop techniques for interactive editing and manipulation of captured mesh sequences with the flexibility associated with conventional computer animation techniques. In particular, the application of Laplacian deformation for animation and compression of surface motion capture data is investigated. Laplacian deformation enables the manipulation of a mesh at a vertex level while maintaining its local geometric properties but lacks a mechanism for ensuring the preservation of its underlying physical structure. Motivated by this limitation, a learnt surface deformation basis constructed in the space of differential cqordinates is introduced. The incorporation of this basis into the Laplacian framework constrains the solution to the space of plausible deformations built from a set of examples, therefore preserving the structure of the mesh. The successful application of this approach to space-time editing together with a set of novel non-linear edit propagation techniques are presented. Representations for efficient storage of surface motion capture sequences, generally comprised of hundreds of frames with thousands of vertices, are investigated. A novel layered representation that exploits the articulated nature of the data is presented and compared with other compression techniques based on PCA and Laplacian deformation, with and without using the aforementioned surface deformation basis. The proposed layered representation achieves consistently high compression ratio with low maximum reconstruction errors in three test sequences from different characters.
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Okamoto, Hiroshi 1968. "Time, speed and perception : intervals in the representation of architectural space." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/37560.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Architecture, 2000.Includes bibliographical references (leaves 52-54).
Although the notion of "space" in architecture is a relatively contemporary one, this research looks at the difference between the conception and representation of space and the actual material reality. With contemporary thought brought about by the modern measure, as architects formalize their ideas in representations, this paper argues that there arises a tendency to quantify and objectify the represented space and discount the experiential nature of the space. This research was initiated in reaction to this tendency to conceive of space as a given, formal static container in search of a wider notion of space as a product of interactions between various dynamics. Using small time based representational design experiments as well as specific precedents of conceptions and representations of space as running parallel points of reference; this investigation explores the element of time as one of the possible components of the various dynamics that produce space. Specifically, a non-chronological look at the modern, contemporary and pre-modern notion of time was taken to explore possible alternative conceptions and representations of space and time, contending that space is neither static or exclusive of time, nor is it a stage set for speed. In other words, this paper concludes that space and time are first and foremost products of experience.
by Hiroshi Okamoto.
S.M.
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Björnberg, Jakob Erik. "Graphical representations of Ising and Potts models stochastic geometry of the quantum Ising model and the space-time Potts model /." Stockholm : Skolan för teknikvetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11267.
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Björnberg, Jakob Erik. "Graphical representations of Ising and Potts models : Stochastic geometry of the quantum Ising model and the space-time Potts model." Doctoral thesis, KTH, Matematik (Inst.), 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11267.
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HTML clipboard Statistical physics seeks to explain macroscopic properties of matter in terms of microscopic interactions. Of particular interest is the phenomenon of phase transition: the sudden changes in macroscopic properties as external conditions are varied. Two models in particular are of great interest to mathematicians, namely the Ising model of a magnet and the percolation model of a porous solid. These models in turn are part of the unifying framework of the random-cluster representation, a model for random graphs which was first studied by Fortuin and Kasteleyn in the 1970’s. The random-cluster representation has proved extremely useful in proving important facts about the Ising model and similar models. In this work we study the corresponding graphical framework for two related models. The first model is the transverse field quantum Ising model, an extension of the original Ising model which was introduced by Lieb, Schultz and Mattis in the 1960’s. The second model is the space–time percolation process, which is closely related to the contact model for the spread of disease. In Chapter 2 we define the appropriate space–time random-cluster model and explore a range of useful probabilistic techniques for studying it. The space– time Potts model emerges as a natural generalization of the quantum Ising model. The basic properties of the phase transitions in these models are treated in this chapter, such as the fact that there is at most one unbounded fk-cluster, and the resulting lower bound on the critical value in 
. In Chapter 3 we develop an alternative graphical representation of the quantum Ising model, called the random-parity representation. This representation is based on the random-current representation of the classical Ising model, and allows us to study in much greater detail the phase transition and critical behaviour. A major aim of this chapter is to prove sharpness of the phase transition in the quantum Ising model—a central issue in the theory— and to establish bounds on some critical exponents. We address these issues by using the random-parity representation to establish certain differential inequalities, integration of which gives the results. In Chapter 4 we explore some consequences and possible extensions of the results established in Chapters 2 and 3. For example, we determine the critical point for the quantum Ising model in and in ‘star-like’ geometries.HTML clipboard Statistisk fysik syftar till att förklara ett materials makroskopiska egenskaper i termer av dess mikroskopiska struktur. En särskilt intressant egenskap är är fenomenet fasövergång, det vill säga en plötslig förändring i de makroskopiska egenskaperna när externa förutsättningar varieras. Två modeller är särskilt intressanta för en matematiker, nämligen Ising-modellen av en magnet och perkolationsmodellen av ett poröst material. Dessa två modeller sammanförs av den så-kallade fk-modellen, en slumpgrafsmodell som först studerades av Fortuin och Kasteleyn på 1970-talet. fk-modellen har sedermera visat sig vara extremt användbar för att bevisa viktiga resultat om Ising-modellen och liknande modeller. I den här avhandlingen studeras den motsvarande grafiska strukturen hos två näraliggande modeller. Den första av dessa är den kvantteoretiska Isingmodellen med transverst fält, vilken är en utveckling av den klassiska Isingmodellen och först studerades av Lieb, Schultz och Mattis på 1960-talet. Den andra modellen är rumtid-perkolation, som är nära besläktad med kontaktmodellen av infektionsspridning. I Kapitel 2 definieras rumtid-fk-modellen, och flera probabilistiska verktyg utforskas för att studera dess grundläggande egenskaper. Vi möter rumtid-Potts-modellen, som uppenbarar sig som en naturlig generalisering av den kvantteoretiska Ising-modellen. De viktigaste egenskaperna hos fasövergången i dessa modeller behandlas i detta kapitel, exempelvis det faktum att det i fk-modellen finns högst en obegränsad komponent, samt den undre gräns för det kritiska värdet som detta innebär. I Kapitel 3 utvecklas en alternativ grafisk framställning av den kvantteoretiska Ising-modellen, den så-kallade slumpparitetsframställningen. Denna är baserad på slumpflödesframställningen av den klassiska Ising-modellen, och är ett verktyg som låter oss studera fasövergången och gränsbeteendet mycket närmare. Huvudsyftet med detta kapitel är att bevisa att fasövergången är skarp—en central egenskap—samt att fastslå olikheter för vissa kritiska exponenter. Metoden består i att använda slumpparitetsframställningen för att härleda vissa differentialolikheter, vilka sedan kan integreras för att lägga fast att gränsen är skarp. I Kapitel 4 utforskas några konsekvenser, samt möjliga vidareutvecklingar, av resultaten i de tidigare kapitlen. Exempelvis bestäms det kritiska värdet hos den kvantteoretiska Ising-modellen på
, samt i ‘stjärnliknankde’ geometrier.QC 20100705
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Björnberg, Jakob Erik. "Graphical representations of Ising and Potts models : stochastic geometry of the quantum Ising model and the space-time Potts model." Thesis, University of Cambridge, 2010. https://www.repository.cam.ac.uk/handle/1810/224774.
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Statistical physics seeks to explain macroscopic properties of matter in terms of microscopic interactions. Of particular interest is the phenomenon of phase transition: the sudden changes in macroscopic properties as external conditions are varied. Two models in particular are of great interest to mathematicians, namely the Ising model of a magnet and the percolation model of a porous solid. These models in turn are part of the unifying framework of the random-cluster representation, a model for random graphs which was first studied by Fortuin and Kasteleyn in the 1970's. The random-cluster representation has proved extremely useful in proving important facts about the Ising model and similar models. In this work we study the corresponding graphical framework for two related models. The first model is the transverse field quantum Ising model, an extension of the original Ising model which was introduced by Lieb, Schultz and Mattis in the 1960's. The second model is the space-time percolation process, which is closely related to the contact model for the spread of disease. In Chapter 2 we define the appropriate 'space-time' random-cluster model and explore a range of useful probabilistic techniques for studying it. The space-time Potts model emerges as a natural generalization of the quantum Ising model. The basic properties of the phase transitions in these models are treated in this chapter, such as the fact that there is at most one unbounded fk-cluster, and the resulting lower bound on the critical value in Z. In Chapter 3 we develop an alternative graphical representation of the quantum Ising model, called the random-parity representation. This representation is based on the random-current representation of the classical Ising model, and allows us to study in much greater detail the phase transition and critical behaviour. A major aim of this chapter is to prove sharpness of the phase transition in the quantum Ising model - a central issue in the theory - and to establish bounds on some critical exponents. We address these issues by using the random-parity representation to establish certain differential inequalities, integration of which give the results. In Chapter 4 we explore some consequences and possible extensions of the results established in Chapters 2 and 3. For example, we determine the critical point for the quantum Ising model in Z and in 'star-like' geometries.
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Sell, Andrea J. "The influence of movement on the directionality of space-time representation mappings." Tallahassee, Florida : Florida State University, 2009. http://etd.lib.fsu.edu/theses/available/etd-10302009-134713/.
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Thesis (M.S.)--Florida State University, 2009.Advisor: Michael Kaschak, Florida State University, College of Arts and Sciences, Dept. of Psychology. Title and description from dissertation home page (viewed on May 14, 2010). Document formatted into pages; contains vii, 25 pages. Includes bibliographical references.
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Borghesani, Valentina. "The neuro-cognitive representation of word meaning resolved in space and time." Thesis, Paris 6, 2017. http://www.theses.fr/2017PA066091/document.
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L'une des capacités humaines fondamentales est la capacité d'interpréter des symboles. Malgré plusieurs décennies de travaux en neuropsychologique et neuroimagerie sur le substrat cognitif et neuronal des représentations sémantiques, de nombreuses questions restent sans réponse. Les présents travaux de thèse tentent de démêler l'un de ces mystères: les substrats neuronaux des différentes composantes du mot sont-ils dissociables? Ce travail comporte deux composantes principales : l'une théorique et l'autre empirique. Dans la première partie, nous passons en revue les différentes positions théoriques concernant les corrélats cognitifs et neuraux des représentations sémantiques. De plus, nous proposons une distinction opérationnelle entre les dimensions moto-perceptives (c'est-à-dire les attributs des objets auxquels les mots se réfèrent perçus par les sens) et conceptuelles (c'est-à-dire l'information construite par l'intégration des multiples caractéristiques perceptives). Dans la deuxième partie, nous présentons les résultats des études menées afin d'étudier l'automaticité de la récupération, l'organisation topographique et la dynamique temporelle des dimensions moto-perceptives et conceptuelles de la signification des mots. Tout en contribuant à notre compréhension de la manière dont le sens des mots est codé dans le cerveau, les travaux présentés dans cette thèse ont des implications méthodologiques et théoriques importantes. En particulier, ils soulignent l'importance d'une intégration fructueuse entre les théories cognitives et les méthodes statistiques avancées afin d'éclairer les mystères entourant les représentations sémantiquesOne of the core human abilities is that of interpreting symbols. Notwithstanding decades of neuropsychological and neuroimaging work on the cognitive and neural substrate of semantic representations, many questions are left unanswered. The research in this dissertation attempts to unravel one of them: are the neural substrates of different components of concrete word meaning dissociated? In the first part, I review the different theoretical positions and empirical findings on the cognitive and neural correlates of semantic representations. Crucially, I propose an operational distinction between motor-perceptual dimensions (i.e., those attributes of the objects referred to by the words that are perceived through the senses) and conceptual ones (i.e., the information that is built via a complex integration of multiple perceptual features). In the second part, I present the results of the studies I conducted in order to investigate the automaticity of retrieval, topographical organization, and temporal dynamics of motor-perceptual and conceptual dimensions of word meaning. The results suggest that the neural substrates of different components of symbol meaning can be dissociated in terms of localization and of the feature of the signal encoding them, while sharing a similar temporal evolution
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Ratan, Naren. "Complex phase space representation of plasma waves : theory and applications." Thesis, University of Oxford, 2017. https://ora.ox.ac.uk/objects/uuid:af5654e3-3137-4d9a-b41d-574cd72103b2.
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This thesis presents results on the description of plasma waves in terms of wavepackets. The wave field is decomposed into a distribution of wavepackets in a space of position, wavevector, time, and frequency. A complex structure joining each pair of Fourier conjugate variables into a single complex coordinate allows the efficient derivation of equations of motion for the phase space distribution by exploiting its analytic properties. The Wick symbol calculus, a mathematical tool generalizing many convenient properties of the Fourier transform to a local setting, is used to derive new exact phase space equations which maintain full information on the phase of the waves and include effects nonlocal in phase space such as harmonic generation. A general purpose asymptotic expansion of the Wick symbol product formula is used to treat dispersion, refraction, photon acceleration, and ponderomotive forces. Examples studied include the nonlinear Schrödinger equation, mode conversion, and the Vlasov equation. The structure of partially coherent wave fields is understood in terms of zeros in the phase space distribution caused by dislocations in its complex phase which are shown to be correlated with the field entropy. Simulations of plasma heating by crossing electron beams are understood by representing the resulting plasma waves in phase space. The local coherence properties of the beam driven Langmuir waves are studied numerically.
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Zhou, Hao. "Representations of Cities in Republican-era Chinese Literature." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1281335246.
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Marques, Alexandre Noll. "A unified discrete-time approach to the state space representation of aeroelastic systems." Instituto Tecnológico de Aeronáutica, 2007. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=350.
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In complex flow situations, it is common to use numerical tools to evaluate the aerodynamic unsteady behavior. The present work presents an alternate formulation for the state space representation of aeroelastic systems based on digital control theory that is shown to be effective and accurate for the coupling of numerical solutions with such systems. The application of the z transform allows for direct frequency domain representations of the aerodynamic solutions without the need for approximating models, as generally occurs in other state space formulations. This fact makes this new methodology also a more straightforward procedure for aeroelastic analyses. A survey on the numerical calculation of impulsive and indicial unsteady aerodynamic responses with modern CFD solvers is also presented. A brief historical background on this subjected is introduced, and it is shown how new interpretations of CFD solvers as discrete-time systems change the way impulsive and indicial responses can be directly obtained. The objective is to demonstrate that the rigorous relationships theoretically established among the aerodynamic responses to impulsive, indicial, harmonic and smooth inputs can be reproduced numerically with modern CFD solvers. Although the numerical results presented herein are obtained with a single CFD tool, the argument is valid for every numerical solution scheme. The CFD tool in question solves the two-dimensional Euler equations with an explicit time march, using a finite volume discretization which supports fully unstructured grids. The results are compared both in the time and in the frequency domains, which yields a more complete understanding of details of the numerical solutions. Finally, typical section models of a flat plate and a NACA 0012 airfoil at subsonic and transonic speed are used as test-cases in order to assess the correctness and accuracy of the proposed aeroelastic analysis methodology. The present results are compared with data obtained from continuous-time state space formulations and through the direct integration of the structural dynamic and aerodynamic equations.
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Woodbury, Nathan Scott. "Representation and Reconstruction of Linear, Time-Invariant Networks." BYU ScholarsArchive, 2019. https://scholarsarchive.byu.edu/etd/7402.
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Network reconstruction is the process of recovering a unique structured representation of some dynamic system using input-output data and some additional knowledge about the structure of the system. Many network reconstruction algorithms have been proposed in recent years, most dealing with the reconstruction of strictly proper networks (i.e., networks that require delays in all dynamics between measured variables). However, no reconstruction technique presently exists capable of recovering both the structure and dynamics of networks where links are proper (delays in dynamics are not required) and not necessarily strictly proper.The ultimate objective of this dissertation is to develop algorithms capable of reconstructing proper networks, and this objective will be addressed in three parts. The first part lays the foundation for the theory of mathematical representations of proper networks, including an exposition on when such networks are well-posed (i.e., physically realizable). The second part studies the notions of abstractions of a network, which are other networks that preserve certain properties of the original network but contain less structural information. As such, abstractions require less a priori information to reconstruct from data than the original network, which allows previously-unsolvable problems to become solvable. The third part addresses our original objective and presents reconstruction algorithms to recover proper networks in both the time domain and in the frequency domain.
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Janoos, Firdaus H. "Spatio-Temporal Representations and Analysis of Brain Function from fMRI." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1295643292.
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Stafford, Francesca. "My pictures are all moments of my life : representations of time and space in the work of Gabriele Munter and Else Lasker-Schuler." Thesis, Lancaster University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288955.
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Klöck, Anja Isabel. "Speed dissolving time and space : technologies of representation and the women of Italian Futurist Theatre /." Diss., ON-CAMPUS Access For University of Minnesota, Twin Cities Click on "Connect to Digital Dissertations", 2000. http://www.lib.umn.edu/articles/proquest.phtml.
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Manthei, Jennifer Judith 1963. "Art of becoming: Space, time, and place in Editora Globo Comics' representation of Brazilian national identities." Thesis, The University of Arizona, 1994. http://hdl.handle.net/10150/278437.
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This work investigates the ideological content of Brazilian comics created under the military dictatorship of 1964-1985. The comics promote a vision of national history and identity that corresponds to the military's focus on industrialization. Brazilian history is portrayed as a peaceful transition to a modern, urban nation of white, middle class, rigidly gendered nuclear families. Despite explicit messages of equality, social groups are implicitly subordinated in a hierarchy of social place according to region, race, ethnicity, class, and gender. Recognizing the processes through which the subordination of social groups is legitimated and protest suppressed is essential to combating inequality in contemporary Brazil.
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Borén, Thomas. "Meeting-places of Transformation : Urban Identity, Spatial Representations and Local Politics in St Petersburg, Russia." Doctoral thesis, Stockholm University, Department of Human Geography, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-412.
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This study develops a model for understanding spatial change and the construction of space as a meeting-place, and then employs it in order to show an otherwise little-known picture of (sub-)urban Russia and its transformation from Soviet times to today. The model is based on time-geographic ideas of time-space as a limited resource in which forces of various kinds struggle for access and form space in interaction with each other. Drawing on cultural semiotics and the concepts of lifeworld and system, the study highlights the social side of these space-forming forces. Based on a long-term fieldwork (participant observation) in Ligovo/Uritsk, a high-rise residential district developed around 1970 and situated on the outskirts of Sankt-Peterburg (St Petersburg), the empirical material concerns processes of urban identity, spatial representations and local politics. The study explicates three codes used to form the image of the city that all relate to its pre-Revolutionary history, two textual strategies of juxtaposition in creating the genius loci of a place, and a discussion of what I call Soviet "stiff landscape" in relation to Soviet mental and ordinary maps of the urban landscape. Moreover, the study shows that the newly implemented self-governing municipalities have not realised their potential as political actors in forming local space, which raises questions on the democratisation of urban space. Finally, the study argues that the model that guides the research is a tool that facilitates the application of the world-view of time-geography and the epistemology of the landscape of courses in concrete research. The study ends with an attempt to generalise spatial change in four types.
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Tse, Yiu-chung, and 謝燿忠. "Postnatal representation of horizontal space in utricle-related central neurons: orientation-specificmaturation time and ionotropic glutamate receptor heterogeneity." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2004. http://hub.hku.hk/bib/B45015028.
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Tran, Antoine. "Object representation in local feature spaces : application to real-time tracking and detection." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLY010/document.
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La représentation visuelle est un problème fondamental en vision par ordinateur. Le but est de réduire l'information au strict nécessaire pour une tâche désirée. Plusieurs types de représentation existent, comme les caractéristiques de couleur (histogrammes, attributs de couleurs...), de forme (dérivées, points d'intérêt...) ou d'autres, comme les bancs de filtres.Les caractéristiques bas-niveau (locales) sont rapides à calculer. Elles ont un pouvoir de représentation limité, mais leur généricité présente un intérêt pour des systèmes autonomes et multi-tâches, puisque les caractéristiques haut-niveau découlent d'elles.Le but de cette thèse est de construire puis d'étudier l'impact de représentations fondées seulement sur des caractéristiques locales de bas-niveau (couleurs, dérivées spatiales) pour deux tâches : la poursuite d'objets génériques, nécessitant des caractéristiques robustes aux variations d'aspect de l'objet et du contexte au cours du temps; la détection d'objets, où la représentation doit décrire une classe d'objets en tenant compte des variations intra-classe. Plutôt que de construire des descripteurs d'objets globaux dédiés, nous nous appuyons entièrement sur les caractéristiques locales et sur des mécanismes statistiques flexibles visant à estimer leur distribution (histogrammes) et leurs co-occurrences (Transformée de Hough Généralisée). La Transformée de Hough Généralisée (THG), créée pour la détection de formes quelconques, consiste à créer une structure de données représentant un objet, une classe... Cette structure, d'abord indexée par l'orientation du gradient, a été étendue à d'autres caractéristiques. Travaillant sur des caractéristiques locales, nous voulons rester proche de la THG originale.En poursuite d'objets, après avoir présenté nos premiers travaux, combinant la THG avec un filtre particulaire (utilisant un histogramme de couleurs), nous présentons un algorithme plus léger et rapide (100fps), plus précis et robuste. Nous présentons une évaluation qualitative et étudierons l'impact des caractéristiques utilisées (espace de couleur, formulation des dérivées partielles...). En détection, nous avons utilisé l'algorithme de Gall appelé forêts de Hough. Notre but est de réduire l'espace de caractéristiques utilisé par Gall, en supprimant celles de type HOG, pour ne garder que les dérivées partielles et les caractéristiques de couleur. Pour compenser cette réduction, nous avons amélioré deux étapes de l'entraînement : le support des descripteurs locaux (patchs) est partiellement produit selon une mesure géométrique, et l'entraînement des nœuds se fait en générant une carte de probabilité spécifique prenant en compte les patchs utilisés pour cette étape. Avec l'espace de caractéristiques réduit, le détecteur n'est pas plus précis. Avec les mêmes caractéristiques que Gall, sur une même durée d'entraînement, nos travaux ont permis d'avoir des résultats identiques, mais avec une variance plus faible et donc une meilleure répétabilitéVisual representation is a fundamental problem in computer vision. The aim is to reduce the information to the strict necessary for a query task. Many types of representation exist, like color features (histograms, color attributes...), shape ones (derivatives, keypoints...) or filterbanks.Low-level (and local) features are fast to compute. Their power of representation are limited, but their genericity have an interest for autonomous or multi-task systems, as higher level ones derivate from them. We aim to build, then study impact of low-level and local feature spaces (color and derivatives only) for two tasks: generic object tracking, requiring features robust to object and environment's aspect changes over the time; object detection, for which the representation should describe object class and cope with intra-class variations.Then, rather than using global object descriptors, we use entirely local features and statisticals mecanisms to estimate their distribution (histograms) and their co-occurrences (Generalized Hough Transform).The Generalized Hough Transform (GHT), created for detection of any shape, consists in building a codebook, originally indexed by gradient orientation, then to diverse features, modeling an object, a class. As we work on local features, we aim to remain close to the original GHT.In tracking, after presenting preliminary works combining the GHT with a particle filter (using color histograms), we present a lighter and fast (100 fps) tracker, more accurate and robust.We present a qualitative evaluation and study the impact of used features (color space, spatial derivative formulation).In detection, we used Gall's Hough Forest. We aim to reduce Gall's feature space and discard HOG features, to keep only derivatives and color ones.To compensate the reduction, we enhanced two steps: the support of local descriptors (patches) are partially chosen using a geometrical measure, and node training is done by using a specific probability map based on patches used at this step.With reduced feature space, the detector is less accurate than with Gall's feature space, but for the same training time, our works lead to identical results, but with higher stability and then better repeatability
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Tse, Yiu-chung. "Postnatal representation of horizontal space in utricle-related central neurons : orientation-specific maturation time and ionotropic glutamate receptor heterogeneity /." View the Table of Contents & Abstract, 2004. http://sunzi.lib.hku.hk/hkuto/record/B30267997.
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Sheehy, Margaret Rita. "Un/making place : a topological analysis of time and space representation in an urban Appalachian seventh grade Civics project /." The Ohio State University, 1999. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488192119263665.
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Mehrens, Patrik. "Mellan ordet och döden : rum, tid och representation i Lars Noréns 70-talslyrik /." Uppsala : [Distributor] Universitetsbiblioteket, 1999. http://catalogue.bnf.fr/ark:/12148/cb37673300c.
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Newhouse, Jack. "Explorations of the Aldous Order on Representations of the Symmetric Group." Scholarship @ Claremont, 2012. https://scholarship.claremont.edu/hmc_theses/35.
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The Aldous order is an ordering of representations of the symmetric group motivated by the Aldous Conjecture, a conjecture about random processes proved in 2009. In general, the Aldous order is very difficult to compute, and the proper relations have yet to be determined even for small cases. However, by restricting the problem down to Young-Jucys-Murphy elements, the problem becomes explicitly combinatorial. This approach has led to many novel insights, whose proofs are simple and elegant. However, there remain many open questions related to the Aldous Order, both in general and for the Young-Jucys-Murphy elements.
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Amaya, Austin J. "Beurling-Lax Representations of Shift-Invariant Spaces, Zero-Pole Data Interpolation, and Dichotomous Transfer Function Realizations: Half-Plane/Continuous-Time Versions." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/27636.
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Given a full-range simply-invariant shift-invariant subspace M of the vector-valued L2 space on the unit circle, the classical Beurling-Lax-Halmos (BLH) theorem obtains a unitary operator-valued function W so that M may be represented as the image of of the Hardy space H2 on the disc under multiplication by W. The work of Ball-Helton later extended this result to find a single function representing a so-called dual shift-invariant pair of subspaces (M,MÃ ) which together form a direct-sum decomposition of L2. In the case where the pair (M,MÃ ) are finite-dimensional perturbations of the Hardy space H2 and its orthogonal complement, Ball-Gohberg-Rodman obtained a transfer function realization for the representing function W; this realization was parameterized in terms of zero-pole data computed from the pair (M,MÃ ). Later work by Ball-Raney extended this analysis to the case of nonrational functions W where the zero-pole data is taken in an infinite-dimensional operator theoretic sense. The current work obtains analogues of these various results for arbitrary dual shift-invariant pairs (M,MÃ ) of the L2 spaces on the real line; here, shift-invariance refers to invariance under the translation group. These new results rely on recent advances in the understanding of continuous-time infinite-dimensional input-state-output linear systems which have been codified in the book by Staffans.Ph. D.
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Anapolitanos, Dionysios Anastasiou. "Leibniz : representation, continuity and the spatiotemporal /." Dordrecht [u.a.] : Kluwer, 1999. http://www.loc.gov/catdir/enhancements/fy0813/98047229-d.html.
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Miloš, Radovanović. "High-Dimensional Data Representations and Metrics for Machine Learning and Data Mining." Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2011. https://www.cris.uns.ac.rs/record.jsf?recordId=77530&source=NDLTD&language=en.
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In the current information age, massive amounts of data are gathered, at a rate prohibiting their effective structuring, analysis, and conversion into useful knowledge. This information overload is manifested both in large numbers of data objects recorded in data sets, and large numbers of attributes, also known as high dimensionality. This dis-sertation deals with problems originating from high dimensionality of data representation, referred to as the “curse of dimensionality,” in the context of machine learning, data mining, and information retrieval. The described research follows two angles: studying the behavior of (dis)similarity metrics with increasing dimensionality, and exploring feature-selection methods, primarily with regard to document representation schemes for text classification. The main results of the dissertation, relevant to the first research angle, include theoretical insights into the concentration behavior of cosine similarity, and a detailed analysis of the phenomenon of hubness, which refers to the tendency of some points in a data set to become hubs by being in-cluded in unexpectedly many k-nearest neighbor lists of other points. The mechanisms behind the phenomenon are studied in detail, both from a theoretical and empirical perspective, linking hubness with the (intrinsic) dimensionality of data, describing its interaction with the cluster structure of data and the information provided by class la-bels, and demonstrating the interplay of the phenomenon and well known algorithms for classification, semi-supervised learning, clustering, and outlier detection, with special consideration being given to time-series classification and information retrieval. Results pertaining to the second research angle include quantification of the interaction between various transformations of high-dimensional document representations, and feature selection, in the context of text classification.U tekućem „informatičkom dobu“, masivne količine podataka sesakupljaju brzinom koja ne dozvoljava njihovo efektivno strukturiranje,analizu, i pretvaranje u korisno znanje. Ovo zasićenje informacijamase manifestuje kako kroz veliki broj objekata uključenihu skupove podataka, tako i kroz veliki broj atributa, takođe poznatkao velika dimenzionalnost. Disertacija se bavi problemima kojiproizilaze iz velike dimenzionalnosti reprezentacije podataka, čestonazivanim „prokletstvom dimenzionalnosti“, u kontekstu mašinskogučenja, data mining-a i information retrieval-a. Opisana istraživanjaprate dva pravca: izučavanje ponašanja metrika (ne)sličnosti u odnosuna rastuću dimenzionalnost, i proučavanje metoda odabira atributa,prvenstveno u interakciji sa tehnikama reprezentacije dokumenata zaklasifikaciju teksta. Centralni rezultati disertacije, relevantni za prvipravac istraživanja, uključuju teorijske uvide u fenomen koncentracijekosinusne mere sličnosti, i detaljnu analizu fenomena habovitosti kojise odnosi na tendenciju nekih tačaka u skupu podataka da postanuhabovi tako što bivaju uvrštene u neočekivano mnogo lista k najbližihsuseda ostalih tačaka. Mehanizmi koji pokreću fenomen detaljno suproučeni, kako iz teorijske tako i iz empirijske perspektive. Habovitostje povezana sa (latentnom) dimenzionalnošću podataka, opisanaje njena interakcija sa strukturom klastera u podacima i informacijamakoje pružaju oznake klasa, i demonstriran je njen efekat napoznate algoritme za klasifikaciju, semi-supervizirano učenje, klasteringi detekciju outlier-a, sa posebnim osvrtom na klasifikaciju vremenskihserija i information retrieval. Rezultati koji se odnose nadrugi pravac istraživanja uključuju kvantifikaciju interakcije izmeđurazličitih transformacija višedimenzionalnih reprezentacija dokumenatai odabira atributa, u kontekstu klasifikacije teksta.
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Dias, Márcio Roberto Soares. "Os espaços móveis da memória na poesia de Carlos Drummond de Andrade." Programa de Pós-Graduação em Letras e Linguística da UFBA, 2009. http://www.repositorio.ufba.br/ri/handle/ri/10735.
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Esta tese orienta-se por uma leitura da lírica drummondiana, através da qual sobressai a análise da relação afetivo cognitiva que o poeta estabelece com elementos (pessoas, espaços, instituições...) perdidos na nebulosa do tempo, evidenciando-se, sobretudo, a mediação da dimensão temporal como recurso dinamizador da relação poesia/espaço. No atrito com o tempo corrosivo, o poeta dedica-se a registrar as conquistas e as perdas da maturidade, enriquecendo sua obra com a expressão das tensões vividas pelo homem que, lúcido, caminha para a dissipação. Por um lado, essa inscrição da existência na série cronológica faz nascer a noção de que a temporalidade é, em si, cega e irreversível, visto a seqüência dos tempos não garantir um traçado evolucionista do inferior para o superior. Por outro lado, a maturidade sobrevinda faculta-lhe um gesto de resistência: o seu deslocamento em direção aos antepassados para compreender a conformação de sua consciência permite-lhe restabelecer laços afetivos, e, nesse processo, recriar lingüisticamente o seu passado. Uma parcela considerável de sua poesia memorialística traz um tom profundamente marcado pela dúvida, pela inquietude, pelo sentimento de culpa. Esse período de autoanálise mais dura faz sua poesia resvalar na mitificação da família e da Minas Gerais de sua infância, o que acaba por lançar sobre si próprio certa suspeição, marcada principalmente pelo motivo do desajuste familiar. A partir de Lição de coisas, já aos 60 anos de idade, e principalmente com Boitempo, observa-se na poesia de Drummond uma disposição biográfica sem a pungência ou a acrimônia que se percebem em outros versos nos quais o poeta trata de si mesmo ao longo de sua obra.
Salvador
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Bouallègue, Sami. "Représentations de l'histoire dans l'œuvre de Julien Gracq." Thesis, Paris 4, 2015. http://www.theses.fr/2015PA040058.
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Notre hypothèse de travail est la suivante : l’œuvre de Gracq, exprime le rapport privilégié que l’auteur entretient avec l’histoire. Il est néanmoins évident que ce lien ne se limite pas à une pure écriture historiographique ou à un simple témoignage. Il s’agit plutôt d’une forme particulière de représentation littéraire qui porte sur un objet complexe : le passé, le présent et le devenir d’un être-là. Notre ambition, à travers le travail sur un corpus de quatre œuvres narratives, est, d’abord, de mettre en rapport l’œuvre littéraire avec le matériau même de l’histoire ainsi qu’avec les autres champs de la connaissance et de la perception avec lesquels la littérature forme un continuum. Lire l’histoire à travers cette œuvre revient dans un premier lieu à saisir cette continuité qu’il y a entre les deux dimensions fondamentales du temps et de l’espace historiques et de son inscription dans l’artefact littéraire qui la transforme en une matière fertile pour une « poésie de l’histoire ». Dans une première étape, nous essaierons de cerner les différentes manières avec lesquelles le temps historique est ressenti puis exprimé à travers la notion d’événement. C’est cette notion d’événement qui nous permettra aussi d’explorer l’espace géographique gracquien à travers les différents statuts qu’il assume dans l’œuvre. La troisième partie tentera de décrire les différents modes discursifs selon lesquels la représentation du temps et de l’espace historiques se transforme en artefact littéraire. Dans cette étude nous nous inspirerons essentiellement des travaux de Paul Ricoeur (Temps et récit, La Mémoire l’Histoire l’Oubli) et de Hayden White dans MetahistoryThe main hypothesis of this thesis is: Julien Gracq’s works are the expressions of a privileged relationship linking the author to History. It is evident, however, that this link is not limited to a pure historiographical writing or to a simple testimony. It is rather a specific form of literary representation that covers a complex issue, namely: the past, the present and evolution of living entities in the universe. Via analyzing a corpus of four narratives, my ambition is to connect the literary works to the other fields of knowledge and cognition, with which literature makes a continuum. Throughout these works, History turns to mean that we must understand the continuity between the two fundamental dimensions of historical time and space, and how they are enshrined into a literary artifact that transforms them into a “poetry of history” (“Poésie de l’histoire”). In a first phase, I will try to identify how historical time is felt and then expressed trough the notion of event. This very notion of event will then enable me to explore gracquian geographical space through the various statutes it takes in the literary work. The third part of this thesis will describe the different discursive strategies used to transform historical time and space into literary artifact. The main inspirations for this thesis are the works of Paul Ricoeur (Temps et récit ; La Mémoire, l’Histoire, l’Oubli) and Hayden White (Metahistory)
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Smas, Lukas. "Transaction Spaces : Consumption Configurations and City Formation." Doctoral thesis, Stockholms universitet, Kulturgeografiska institutionen, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7419.
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Consumption forms and is formed by the city. How, when and where commodities are transacted is essential in this urban drama of mutual relationships. This thesis explores how consumption and everyday life in cities are interrelated. The specific objective is to analyse how commodity transaction situations are configured and constrained in time and space, and, how consumer service spaces are formed in and are part of city formation. Transactions are conceptualised as economically and socially situated material projects constituted by consumers, commodities and producers. Commodities and values are transferred and created through transaction spaces. The theoretical perspective is framed around consumption and production of spaces, and particularly informed by Hägerstrand’s time-geographical thinking and Lefebvre’s work on urban space. Methodologically different examples of consumption projects and spaces are used to discuss configurations and formations for commodity transactions. The thesis stresses material and time-spatial constraints for commodity transaction and it discusses the blurring of boundaries between what conventionally has been separate social and economic activities and places. Changing transaction configurations and the formation of consumer service spaces in the city are explored through analysis of different consumption places and commodities such as books, coffee and clothes and property development projects in Stockholm city centre. Transaction configurations display geographical and historical continuities and changes as well as time-spatial flexibility and spatial fixity. Transactions spaces are continuously formed and reformed through processes embedded in the global cultural economy, urban development and politics, as well as through people’s everyday life. Producers’ strategic production and consumers’ tactical appropriation of transactions spaces are accentuated as crucial in the spatial practice of transactions, places and city formation.
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Solstad, Trygve. "Neural representations of Euclidean space." Doctoral thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for nevromedisin, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-6060.
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Moderne nevrovitenskap bygger på antagelsen om at kognitive fenomener som bevissthet, hukommelse, og stedsans oppstår fra den samlede aktiviteten av individuelle nerveceller. Hjerneområdene hippocampus og entorhinal cortex (EC) er kritiske for hukommelse og stedsans hos både mennesker og dyr. Hos rotter utgjør ’stedceller’ i hippocampus egne kart for hvert miljø rotta utforsker mens ’gitterceller’ i EC utgjør et koordinatsystem som passer til alle miljøer. Både kart og koordinatsystem finnes i ulike skalaer i den øverste (dorsale) delen av hjerneområdene mens det hittil har vært uklart om dypere (ventrale) deler er involvert i stedsansen. Vi angrep spørsmålet ved å måle aktiviteten i enkeltceller langs hele lengden av begge hjerneområder hos rotter som løp frem og tilbake på en 18m spesialkonstruert løpebane, og fant stedceller og gitterceller langs hele lengden av begge hjerneområdene (Artikkel II og III). Skalaen til både stedcellene og gittercellene økte fra å representere steder på mindre enn 1m i den dorsale enden til opp mot 10 meter i den ventrale enden av hjerneområdene. Videre utviklet vi en matematisk modell for hvordan minnekart i hippocampus kan være knyttet til stedskoordinater i EC (Artikkel I), og kom fram til et koblingsskjema mellom gitterceller og stedceller som utnytter den systematiske økningen i skala fra dorsal til ventral. Modellen stemmer godt med de anatomiske koblingene mellom EC og hippocampus, og får støtte av nye eksperimentelle data. Til slutt undersøkte vi hvordan stedskartene i hippocampus er knyttet til miljøets utforming. Tidligere matematiske beregninger har vist at kartenes geometriske forankring kan forklares hvis det finnes en tredje celletype som signaliserer rottas avstand og retning til ulike grenser i miljøet. Vi målte aktivitet i enkeltceller i EC mens rotter utforsket miljøer med ulike geometriske former(Artikkel IV). Blant de andre celletypene fant vi en liten gruppe ”grenseceller” som bare er aktive når rotta løper i nærheten av en vegg eller bordkant. Avhandlingen fremlegger ny evidens for at beregning av hierarkisk organisert stedsinformasjon er et grunnprinsipp for hvordan hippocampus og EC fungerer (f.eks. ved behandling av minner), påviser en hittil ukjent enhet for representasjon av geometri i EC, og antyder hvordan nevrale enheter kan samhandle for å støtte opp under kognitive funksjoner som stedsans og hukommelse.As cognitive phenomena are believed to arise from neural activity, uncovering how neurons represent Euclidean one- and two-dimensional space provides a foundation for understanding how the brain organizes and processes information about terrestrial objects and events. Neurons in the hippocampus and medial entorhinal cortex (MEC) of rats exhibit discrete spatial receptive fields at a scale that increases with the neuron’s distance from the dorsal pole of both structures. To find out whether spatial processing is a cardinal function of these structures, we recorded neural activity along the dorsal-most 85% of the CA3 area of the hippocampus (Paper II), and dorsal-most 75% of the MEC (Paper III) while rats explored an 18m linear track. Neurons at all dorsoventral levels of both structures displayed spatial receptive fields, implying functional homogeneity within the hippocampus and MEC. Spatial scale increased from dorsal to ventral in both CA3 and MEC. In hippocampus, field length ranged from less than 1m to more than 10m. In the MEC field length ranged from less than 50cm to approximately 3m, and inter-peak distance ranged from less than 1m to at least 8m. The parallel increase in spatial scale suggests a simple transformation from the repetitive spatial metric of grid cells to the unary place-cell representation of space. Developing a mathematical firing-rate model of place-cell activity to exploit this fact, we showed that place fields can be formed from converging grid-cell inputs that cover a range of spatial scales and orientations but have an overlapping firing peak in the placefield center (Paper I). Inferring metric relationships between entities in hippocampal association maps may therefore rely on interaction with the MEC coordinate system. Because metric information is in turn contingent on the geometric layout of the external environment, we initiated a search for neural representations of geometric features in the parahippocampus. A small proportion (< 10%) of cells that discharged close to environmental borders was found in all cellular layers of MEC as well as in pre- and parasubiculum (Paper IV). ‘Border cells’ typically had a firing field apposing one or more walls of the recording enclosure regardless of enclosure shape, size, or which room the rat was exploring, and responded to any wall, drop, or partition that impeded the rat’s exploration. Taken together, this thesis demonstrates that hierarchically organized spatial processing is an integral property of the hippocampus and MEC, extends the evidence for a modular organization of spatial cognition, and suggests how such modules may interact to support behaviorally relevant functions like spatial memory and navigation.
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Fantinel, Letícia Dias. "Cultura organizacional, lugar e memória : representações de espaço e tempo em dois restaurantes em Porto Alegre." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/15022.
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Este estudo busca desvendar aspectos da cultura organizacional de dois restaurantes pertencentes à mesma rede, compreendendo sua dimensão simbólica através de representações de espaço e tempo, e desenvolvendo comparações acerca de suas semelhanças e diferenças. Em virtude da complexidade do tema, foram utilizados aportes teóricos da Antropologia e outras ciências humanas. Partese do pressuposto de que a compreensão das representações sociais pode servir de fundamento para a interpretação do universo simbólico organizacional. Sob essa ótica, a adaptação dos modelos de gestão à cultura organizacional é uma maneira de gerarem-se ações administrativas que respondam às necessidades organizacionais. Uma das organizações localiza-se no centro histórico da capital gaúcha (Chalé da Praça XV, um espaço antigo, anteriormente valorizado e hoje um tanto degradado sob vários aspectos), e a outra, em um shopping center (Bistrô do shopping, relativamente distante do centro, área privada, mais valorizada pela população). O método etnográfico foi utilizado na identificação das representações que circulam nos dois espaços. As visitas foram realizadas em iguais períodos de tempo em ambos os restaurantes, totalizando um período de cinco meses em campo. Foram identificadas as representações de tempo e espaço elaboradas por funcionários, clientes e administradores das duas organizações, e desvendadas as homogeneidades e heterogeneidades das culturas organizacionais presentes nas duas empresas, sob a perspectiva das representações encontradas. As categorias de análise foram as seguintes: contexto em que os restaurantes estão inseridos, diferentes espaços e tempos dos restaurantes, relação com o passado da cidade, uniformes dos garçons, cardápios, música ao vivo, supervisão e gerência, clientes e representações acerca do outro restaurante. Os resultados indicam que as categorias de análise estabelecidas evidenciaram as heterogeneidades presentes nos dois espaços: o Bistrô, enquanto caracterizado como não-lugar, e o Chalé, lugar antropológico. Fez-se uma relação entre o que ocorre nos dois restaurantes e o que acontece no restante da cidade. Por fim, colocam-se algumas alternativas para que se pense a gestão dos estabelecimentos, atualmente administrados de maneira muito semelhante.This study aims at bringing to light aspects of the organizational culture of two restaurants that belong to the same company, understanding their simbolic dimension by researching representations of space and time, and making comparisons where similarities and differences might be established. Because of the complexity of the subject, theoretical concepts and frameworks from Social Anthropology and other human sciences were used. We understand that the comprehension of social representations can support the interpretation of the organizational simbolic universe. From this point of view, adaptating the management models to the organizational culture is a way of providing effective management actions. One of the organizations is placed on historic center of the capital of Rio Grande do Sul (Chalé da Praça XV, an ancient space, place valued in the past, but nowadays it´s considered a victim of urban degradation), and another, located inside a shopping mall (Bistrô do shopping, a little far from center, private and commercial area, space valued by local population). The etnographic method has been used to bring to light representations present in both spaces. The etnographic fieldwork was conducted in both restaurants, on demanding a period of five months. Representations of time and space produced by employees, clients and managers of both organizations were identifyed, putting under the spot similarities and differences of organizational cultures, from the perspective of the representations found. The analysis categories were: context of the restaurants, different spaces and times, relationship with the past of the city, waiters´ uniforms, menus, live music, supervision and management, clients e representations about the other restaurant. The results show that the analysis categories established make clear the differences present in both organizations: the Bistrô, while seemed like a non-place, and the Chalé, like an anthropological place. It was done a comparison between both restaurants and the city in general. At the end, some alternatives were presented to help to define the management in those cases, nowadays done on a very similar way.
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Mitchell, Phillipa Marlis. "Accessing the in between: The conditions of possibility emerging from interactions with information and communications technologies in Auckland, New Zealand." Thesis, University of Auckland, 2009. http://hdl.handle.net/2292/3456.
Full textAbstract:
The complex interactions between individuals, institutions and information and communications technologies (ICTs) have generated a growing body of research that seeks greater knowledge of the processes at work and their consequences. Situated firmly within this area, this thesis challenges the dominance of the generalised and largely technologically deterministic narratives within the field by seeking to constitute such knowledge in a different way. Geography provides a useful standpoint from which to challenge these narratives owing to its enduring engagement with time and space, concepts implicit in any discussion of ICTs effects. Emerging work on code space, transurbanism and timespace are specifically used to negate the persistent dualistic treatment of time and space which is argued to be hampering geographic research in this field. Methodologically drawing from a non representational style this thesis uses these emerging understandings to access the in between, a mental space of performance; which involves the process of drawing from tacit knowledge, cognitive perceptions of the spatial and temporal environment and emotions, in order to explore the conditions of possibility that individuals are becoming aware of through their interactions with ICTs. Four empirical interventions are used to ground these emerging understandings into the reality of everyday encounters with ICTs in Auckland, New Zealand. The first focuses on the role of local government in the development of Auckland’s ICT infrastructure, a complex and contingent process. The second concentrates on the provision of a Real Time Passenger Information System at Auckland bus stops, exposing individuals to new timespaces while waiting for the bus. The third considers students opinions of the e-learning mechanisms used in two first year geography courses. The final intervention examines the role ICTs play in South Africans and South Koreans imagining, negotiation and mediation of the migration process to Auckland. In conclusion, this thesis contributes to how geography constitutes knowledge about ICTs at three different levels. Empirically, the four interventions contribute grounded findings to the debates in the geographic literature over interactions with ICTs. Methodologically, the conditions of possibility institutional and individual actors are beginning to perceive through their encounters with ICTs are revealed as are the timespaces that may eventuate from these. Theoretically, to understand how the interactions between individuals and ICTs are performed this thesis demonstrates the need to interrogate the in between as a process, not just a gap or blank.
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Canzoneri, Elisa <1984>. "Plasticity in body and peripersonal space representations." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amsdottorato.unibo.it/5895/.
Full textAbstract:
A successful interaction with objects in the environment requires integrating
information concerning object-location with the shape, dimension and position of body parts in space. The former information is coded in a multisensory representation of the space around the body, i.e. peripersonal space (PPS), whereas the latter is enabled by an online, constantly updated, action-orientated multisensory representation of the body (BR) that is critical for action. One of the critical features of these representations is that both PPS and BR are not fixed, but they dynamically change depending on different types of experience. In a series of experiment, I studied plastic properties of PPS and BR in humans. I have developed a series of methods to measure the boundaries of PPS representation (Chapter 4), to study its neural correlates (Chapter 3) and to assess BRs. These tasks have been used to study changes in PPS and BR following tool-use (Chapter 5), multisensory stimulation (Chapter 6), amputation and prosthesis implantation (Chapter 7) or social interaction (Chapter 8). I found that changes in the function (tool-use) and the structure (amputation and prosthesis implantation) of the physical body elongate or shrink both PPS and BR. Social context and social interaction also shape PPS representation. Such high degree of plasticity suggests that our sense of body in space is not given at once, but it is constantly constructed and adapted through experience.Allo scopo di interagire con oggetti presenti nell’ambiente esterno è necessario integrare le informazioni sulla posizione degli oggetti nello spazio con informazioni riguardanti la forma, dimensione e posizione delle singole parti del corpo rispetto all’oggetto stesso. Due diverse rappresentazioni supportano la codifica di tali informazioni: da una parte, la rappresentazione dello Spazio Peripersonale, una rappresentazione multisensoriale dello spazio intorno al corpo, e dall’altra una rappresentazione multisensoriale del corpo, costantemente aggiornata e orientata all’azione. Una caratteristica critica di queste rappresentazioni è rappresentata dalle loro proprietà plastiche, cioè dalla possibilità di modificarsi in seguito a diversi tipi di esperienza. In questa tesi mi sono focalizzata sullo studio delle proprietà plastiche delle rappresentazioni del corpo e dello spazio peripersonale. Ho sviluppato una serie di metodi per valutare il confine dello spazio peripersonale (Capitolo 4), per studiare i suoi correlati neurali (Capitolo 3) e per valutare le rappresentazioni multisensoriali del corpo. Questi compiti sono stati usati per studiare modificazioni plastiche del corpo e dello spazio peripersonale in seguito all’utilizzo di uno strumento (Capitolo 5), in seguito a una stimolazione multisensoriale (Capitolo 6), amputazione e impianto di protesi (Capitolo 7) e nell’ambito delle interazioni sociali. I risultati ottenuti hanno mostrato come la modificazione nella funzione (in seguito all’utilizzo di uno strumento) o della struttura fisica (in seguito ad amputazione ed impianto di protesi) del corpo determinano una estensione o una contrazione sia della rappresentazione dello spazio peripersonale che della rappresentazione del corpo. Inoltre, i risultati ottenuti hanno dimostrato che la rappresentazione dello spazio peripersonale viene plasmata anche dalle interazioni sociali. Tale livello di plasticità suggerisce che l’esperienza del nostro corpo viene continuata costruita e aggiornata tramite le diverse esperienze.
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Blacker, U. "Representations of space in contemporary Ukrainian literature." Thesis, University College London (University of London), 2011. http://discovery.ucl.ac.uk/1318068/.
Full textAbstract:
The thesis examines representations of space in Ukrainian literature from the late 1980s to the late 2000s. It argues that space in this period became an important preoccupation for Ukrainian writers. Representations of cities, architecture, regions, geopolitical spaces, the spaces of the home and of the body became common tropes through which authors tackled the pressing cultural and political issues of the era, and sought cultural and personal identity. The thesis discusses a wide range of leading contemporary Ukrainian authors, looking at their use of space and the aesthetic, cultural and political implications of this use. The thesis is divided into four chapters. The first focuses on the carnivalesque urban writing of the late 1980s and early 1990s, the second on postcolonial and post-Soviet space, the third on gendered space, and the final chapter on the relationship between time, space and text. The thesis argues that the preoccupation with space defined the way in which Ukrainian literature represented the world in the period in question, placing space as an equal and often privileged dimension over time. The second important consequence of this was the development of a spatial conception of text and language itself. The thesis demonstrates that in order to understand Ukrainian literature of the post-independence period, it is necessary to think of it in terms of space. It also argues that study of these texts can provide an understanding of space, both in literature and beyond it.
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Karacayir, Murat. "Space-time Codes." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612028/index.pdf.
Full textAbstract:
The phenomenon of fading constitutes a fundamental problem in wireless communications. Researchers have proposed many methods to improve the reliability of communication over wireless channels in the presence of fading. Many studies on this topic have focused on diversity techniques. Transmit diversity is a common diversity type in which multiple antennas are employed at the transmitter. Space-time coding is a technique based on transmit diversity introduced by Tarokh et alii in 1998.
In this thesis, various types of space-time codes are examined. Since they were originally introduced in the form of trellis codes, a major part is devoted to space-time trellis codes where the fundamental design criteria are established. Then, space-time block coding, which presents a different approach, is introduced and orthogonal spacetime block codes are analyzed in some detail. Lastly, rank codes from coding theory
are studied and their relation to space-time coding are investigated.
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Dowker, Fay H. "Space-time wormholes." Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359554.
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Lamahewa, Tharaka Anuradha, and tharaka lamahewa@anu edu au. "Space-Time Coding and Space-Time Channel Modelling for Wireless Communications." The Australian National University. Research School of Information Sciences and Engineering, 2007. http://thesis.anu.edu.au./public/adt-ANU20070816.152647.
Full textAbstract:
In this thesis we investigate the effects of the physical
constraints such as antenna aperture size, antenna geometry and
non-isotropic scattering distribution parameters (angle of
arrival/departure and angular spread) on the performance of coherent
and non-coherent space-time coded wireless communication systems.
First, we derive analytical expressions for the exact pairwise error
probability (PEP) and PEP upper-bound of coherent and non-coherent
space-time coded systems operating over spatially correlated fading
channels using a moment-generating function-based approach. These
analytical expressions account for antenna spacing, antenna
geometries and scattering distribution models. Using these new PEP
expressions, the degree of the effect of antenna spacing, antenna
geometry and angular spread is quantified on the diversity advantage
(robustness) given by a space-time code. It is shown that the number
of antennas that can be employed in a fixed antenna aperture without
diminishing the diversity advantage of a space-time code is
determined by the size of the antenna aperture, antenna geometry and
the richness of the scattering environment.
¶
In realistic channel environments the performance of space-time
coded multiple-input multiple output (MIMO) systems is significantly
reduced due to non-ideal antenna placement and non-isotropic
scattering. In this thesis, by exploiting the spatial dimension of a
MIMO channel we introduce the novel use of linear spatial precoding
(or power-loading) based on fixed and known parameters of MIMO
channels to ameliorate the effects of non-ideal antenna placement on
the performance of coherent and non-coherent space-time codes. The
spatial precoder virtually arranges the antennas into an optimal
configuration so that the spatial correlation between all antenna
elements is minimum. With this design, the precoder is fixed for
fixed antenna placement and the transmitter does not require any
feedback of channel state information (partial or full) from the
receiver. We also derive precoding schemes to exploit non-isotropic
scattering distribution parameters of the scattering channel to
improve the performance of space-time codes applied on MIMO systems
in non-isotropic scattering environments. However, these schemes
require the receiver to estimate the non-isotropic parameters and
feed them back to the transmitter.
¶
The idea of precoding based on fixed parameters of MIMO channels is
extended to maximize the capacity of spatially constrained dense
antenna arrays. It is shown that the theoretical maximum capacity
available from a fixed region of space can be achieved by power
loading based on previously unutilized channel state information
contained in the antenna locations. We analyzed the correlation
between different modal orders generated at the transmitter region
due to spatially constrained antenna arrays in non-isotropic
scattering environments, and showed that adjacent modes contribute
to higher correlation at the transmitter region. Based on this
result, a power loading scheme is proposed which reduces the effects
of correlation between adjacent modes at the transmitter region by
nulling power onto adjacent transmit modes.
¶
Furthermore, in this thesis a general space-time channel model for
down-link transmission in a mobile multiple antenna communication
system is developed. The model incorporates deterministic
quantities such as physical antenna positions and the motion of the
mobile unit (velocity and the direction), and random quantities to
capture random scattering environment modeled using a bi-angular
power distribution and, in the simplest case, the covariance between
transmit and receive angles which captures statistical
interdependency. The Kronecker model is shown to be a special case
when the power distribution is separable and is shown to
overestimate MIMO system performance whenever there is more than one
scattering cluster. Expressions for space-time cross correlations
and space-frequency cross spectra are given for a number of
scattering distributions using Gaussian and Morgenstern's family of
multivariate distributions. These new expressions extend the
classical Jake's and Clarke's correlation models to general
non-isotropic scattering environments.
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Lamahewa, Tharaka Anuradha. "Space-time coding and space-time channel modelling for wireless communications /." View thesis entry in Australian Digital Theses Program, 2006. http://thesis.anu.edu.au/public/adt-ANU20070816.152647/index.html.
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Koller, Michael Dominik Fabian. "Topologies on the set of Banach space representations /." [S.l.] : [s.n.], 1993. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=10075.
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Huang, Ruey-Song. "Multisensory representations of space multimodal brain imaging approaches /." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3214724.
Full textAbstract:
Thesis (Ph. D.)--University of California, San Diego, 2006.Title from first page of PDF file (viewed July 11, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
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Mejía, Israel Moreno. "Representations of the space of n-theta functions." Thesis, Durham University, 2003. http://etheses.dur.ac.uk/3689/.
Full textAbstract:
Let X be a smooth complex projective curve with group of automorphisms G. In this thesis we apply the Holomorphic Lefschetz Theorem in certain cases to compute the decomposition of the space H (J(_x),O(_n)O)) into a sum of irreducible representations of G, where J(_x) is the Jacobian variety of X and O(O) is the theta line bundle of J(_x). Namely we compute this decomposition in the cases when X is the Klein quartic curve, the Bring curve of genus 4 and the Macbeath curve of genus 7.
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Minor, Sue Blose. "Children's understanding of projective space in two-dimensional representations of three-dimensional space /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487688973683519.
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Haron, Linariza. "Facility space-time management." Thesis, University College London (University of London), 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326152.
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Thompson, Philip R. Z. (Philip Reed Zane). "Space, time and acoustics." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/78997.
Full textAbstract:
Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 1988.Includes bibliographical references (leaves 156-159).
This thesis describes the development of new concepts in acoustical analysis from their inception to implementation as a computer design tool. Research is focused on a computer program which aids the designer to visually conceive the interactions of acoustics within a geometrical~y defined environment by synthesizing the propagation of sound in a three dimensional space over time. Information is communicated through a unique use of images that are better suited for interfacing with the design process. The first part of this thesis describes the concepts behind the development of a graphic acoustical rendering program to a working level. This involves the development of a computer ray tracing prototype that is sufficiently powerful to explore the issues facing this new design and analysis methodology. The second part uses this program to evaluate existing performance spaces in order to establish qualitative criteria in a new visual format. Representational issues relating to the visual perception of acoustic spaces are also explored. In the third part, the program is integrated into the design process. I apply this acoustical tool to an actual design situation by remodeling a large performance hall in Medford, Massachusetts. Chevalier Auditorium is a real project, commissioned by the city of Medford, whose program requirements closely match my intentions in scope, scale and nature of a design for exploring this new acoustical analysis and design methodology. Finally, I summarize this program's effectiveness and discuss its potential in more sophisticated future design environments.
by Philip R.Z. Thompson.
M.Arch.
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Sanders, Ralph Jarrett. "Space, time, and silence." Thesis, Virginia Polytechnic Institute and State University, 1990. http://hdl.handle.net/10919/56200.
Full textAbstract:
This thesis is a meditation upon silence, upon its ontological relationship to architecture. As such, it relies more upon insight and contemplation than analysis. It seeks to explore this realm through the making of a trappist monastery, to ask fundamental questions about the nature of human dwelling in the most complete sense, to stir the memory and perhaps to move the heart toward that silence which is beyond thought, which precedes and bounds and yet pervades all human experience.Master of Architecture