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Ratto, Diego. "Electroacoustic Orchestration : Timbre, Space and Sound Material Organisation." Thesis, Kungl. Musikhögskolan, Institutionen för komposition, dirigering och musikteori, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kmh:diva-3144.
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As a composer of electroacoustic music, I’m interested in understanding which characteristics of classical orchestration can be used in electroacoustic music after these years of its development. In specific, which aspects of orchestration can be used as powerful techniques in acousmatic music? The aim of this study is to create connections between the conventional acoustic orchestration practice and electroacoustic orchestration by using a transfer2 technique.
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Nicol, Craig Andrew. "Development and exploration of a timbre space representation of audio." Thesis, University of Glasgow, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426612.
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Roche, Fanny. "Music sound synthesis using machine learning : Towards a perceptually relevant control space." Thesis, Université Grenoble Alpes, 2020. http://www.theses.fr/2020GRALT034.
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Un des enjeux majeurs du marché des synthétiseurs et de la recherche en synthèse sonore aujourd'hui est de proposer une nouvelle forme de synthèse permettant de générer des sons inédits tout en offrant aux utilisateurs de nouveaux contrôles plus intuitifs afin de les aider dans leur recherche de sons. En effet, les synthétiseurs sont actuellement des outils très puissants qui offrent aux musiciens une large palette de possibilités pour la création de textures sonores, mais également souvent très complexes avec des paramètres de contrôle dont la manipulation nécessite généralement des connaissances expertes. Cette thèse s'intéresse ainsi au développement et à l'évaluation de nouvelles méthodes d'apprentissage machine pour la synthèse sonore permettant la génération de nouveaux sons de qualité tout en fournissant des paramètres de contrôle pertinents perceptivement.Le premier challenge que nous avons relevé a donc été de caractériser perceptivement le timbre musical synthétique en mettant en évidence un jeu de descripteurs verbaux utilisés fréquemment et de manière consensuelle par les musiciens. Deux études perceptives ont été menées : un test de verbalisation libre qui nous a permis de sélectionner huit termes communément utilisés pour décrire des sons de synthétiseurs, et une analyse à échelles sémantiques permettant d'évaluer quantitativement l'utilisation de ces termes pour caractériser un sous-ensemble de sons, ainsi que d'analyser leur "degré de consensualité".Dans un second temps, nous avons exploré l'utilisation d'algorithmes d'apprentissage machine pour l'extraction d'un espace de représentation haut-niveau avec des propriétés intéressantes d'interpolation et d'extrapolation à partir d'une base de données de sons, le but étant de mettre en relation cet espace avec les dimensions perceptives mises en évidence plus tôt. S'inspirant de précédentes études sur la synthèse sonore par apprentissage profond, nous nous sommes concentrés sur des modèles du type autoencodeur et avons réalisé une étude comparative approfondie de plusieurs types d'autoencodeurs sur deux jeux de données différents. Ces expériences, couplées avec une étude qualitative via un prototype non temps-réel développé durant la thèse, nous ont permis de valider les autoencodeurs, et en particulier l'autoencodeur variationnel (VAE), comme des outils bien adaptés à l'extraction d'un espace latent de haut-niveau dans lequel il est possible de se déplacer de manière continue et fluide en créant de tous nouveaux sons. Cependant, à ce niveau, aucun lien entre cet espace latent et les dimensions perceptives mises en évidence précédemment n'a pu être établi spontanément.Pour finir, nous avons donc apporté de la supervision au VAE en ajoutant une régularisation perceptive durant la phase d'apprentissage. En utilisant les échantillons sonores résultant du test perceptif avec échelles sémantiques labellisés suivant les huit dimensions perceptives, il a été possible de contraindre, dans une certaine mesure, certaines dimensions de l'espace latent extrait par le VAE afin qu'elles coïncident avec ces dimensions. Un test comparatif a été finalement réalisé afin d'évaluer l'efficacité de cette régularisation supplémentaire pour conditionner le modèle et permettre un contrôle perceptif (au moins partiel) de la synthèse sonore<br>One of the main challenges of the synthesizer market and the research in sound synthesis nowadays lies in proposing new forms of synthesis allowing the creation of brand new sonorities while offering musicians more intuitive and perceptually meaningful controls to help them reach the perfect sound more easily. Indeed, today's synthesizers are very powerful tools that provide musicians with a considerable amount of possibilities for creating sonic textures, but the control of parameters still lacks user-friendliness and may require some expert knowledge about the underlying generative processes. In this thesis, we are interested in developing and evaluating new data-driven machine learning methods for music sound synthesis allowing the generation of brand new high-quality sounds while providing high-level perceptually meaningful control parameters.The first challenge of this thesis was thus to characterize the musical synthetic timbre by evidencing a set of perceptual verbal descriptors that are both frequently and consensually used by musicians. Two perceptual studies were then conducted: a free verbalization test enabling us to select eight different commonly used terms for describing synthesizer sounds, and a semantic scale analysis enabling us to quantitatively evaluate the use of these terms to characterize a subset of synthetic sounds, as well as analyze how consensual they were.In a second phase, we investigated the use of machine learning algorithms to extract a high-level representation space with interesting interpolation and extrapolation properties from a dataset of sounds, the goal being to relate this space with the perceptual dimensions evidenced earlier. Following previous studies interested in using deep learning for music sound synthesis, we focused on autoencoder models and realized an extensive comparative study of several kinds of autoencoders on two different datasets. These experiments, together with a qualitative analysis made with a non real-time prototype developed during the thesis, allowed us to validate the use of such models, and in particular the use of the variational autoencoder (VAE), as relevant tools for extracting a high-level latent space in which we can navigate smoothly and create new sounds. However, so far, no link between this latent space and the perceptual dimensions evidenced by the perceptual tests emerged naturally.As a final step, we thus tried to enforce perceptual supervision of the VAE by adding a regularization during the training phase. Using the subset of synthetic sounds used in the second perceptual test and the corresponding perceptual grades along the eight perceptual dimensions provided by the semantic scale analysis, it was possible to constraint, to a certain extent, some dimensions of the VAE high-level latent space so as to match these perceptual dimensions. A final comparative test was then conducted in order to evaluate the efficiency of this additional regularization for conditioning the model and (partially) leading to a perceptual control of music sound synthesis
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Mupona, Gaylord Tonderai. "Development of space truss systems in timber." Thesis, University of Cape Town, 2004. http://hdl.handle.net/11427/6712.
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Space trusses are a valuable structural form for architects and structural engineers due mainly to their efficiency in providing large unobstructed areas, associated with faster erection speeds and low maintenance cost. Most space trusses are made of steel and aluminium whilst a few are of timber. Interest is now shifting from the traditional use of timber in plane trusses of relatively short span, to new structural forms for medium to long spans. In adopting such systems in timber for non-traditional roofing applications, the challenge lies in developing structurally sound, visually neat and economically reproducible connectors for 3-dimensional configurations of timber members. The research aimed at developing a new connector for double and triple-layer space grids in timber, intended for medium-span lightweight roofing applications. The origins of the connector date back to 1995, when it was first proposed by Zingoni as the 14FTC-U Timber Space-Truss Connector, and subsequently tested under laboratory conditions over the three years that followed. Unlike connectors for timber space grids proposed by earlier investigators, or the proprietary connector systems that are available for constructions in steel and aluminium, the 14FTC-U connector features a central core of wood in the form of a cuboctahedron or its variants, upon whose faces are attached U-shaped metal brackets that take the timber members. Thus the connector unit is predominantly wood, giving it considerable aesthetic advantages over its all-metal counterparts. While promising, the structural performance of the original connector was not adequate for practical application, hence a programme of further development was embarked upon. As reported in the thesis, the improvements of the connector have culminated in a structurally viable unit that has been successfully employed in a prototype double-layer timber grid.
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Werneck, Nicolau Leal. "Analise da distorção musical de guitarras eletricas." [s.n.], 2007. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259107.
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Orientador: Furio Damiani<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação<br>Made available in DSpace on 2018-08-11T03:06:29Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007<br>Resumo: Existem diversos problemas ligados à análise de sinais musicais que podem se beneficiar de um conhecimento mais detalhado da estrutura dos sinais gerados pelos diferentes instrumentos. Entre eles se destaca a compressão de sinais baseada em áudio estruturado, onde o codificador determina a partir de um sinal parâmetros para reproduzí-lo com um sintetizador inspirado em modelos físicos dos instrumentos. Para realizar este tipo de análise e síntese é necessário conhecermos as características físicas dos instrumentos e dos sinais produzidos. Este conhecimento é ainda útil para auxiliar no desenvolvimento de instrumentos e outros equipamentos utilizados por músicos para obter o timbre desejado. Esta dissertação apresenta experimentos realizados com uma guitarra elétrica para revelar a dinâmica não-linear de suas cordas e seu filtro linear associado, comparação de sinais gravados com resultados esperados por modelos matemáticos da forma de onda, e ainda uma proposta de uma potencial técnica para a medição de parâmetros para um modelo matemático de um circuito de distorção musical, além de uma maneira de se mapear um par destes parâmetros para um espaço de maior significado psicoacústico<br>Resumo: Existem diversos problemas ligados à análise de sinais musicais que podem se beneficiar de um conhecimento mais detalhado da estrutura dos sinais gerados pelos diferentes instrumentos. Entre eles se destaca a compressão de sinais baseada em áudio estruturado, onde o codificador determina a partir de um sinal parâmetros para reproduzí-lo com um sintetizador inspirado em modelos físicos dos instrumentos. Para realizar este tipo de análise e síntese é necessário conhecermos as características físicas dos instrumentos e dos sinais produzidos. Este conhecimento é ainda útil para auxiliar no desenvolvimento de instrumentos e outros equipamentos utilizados por músicos para obter o timbre desejado. Esta dissertação apresenta experimentos realizados com uma guitarra elétrica para revelar a dinâmica não-linear de suas cordas e seu filtro linear associado, comparação de sinais gravados com resultados esperados por modelos matemáticos da forma de onda, e ainda uma proposta de uma potencial técnica para a medição de parâmetros para um modelo matemático de um circuito de distorção musical, além de uma maneira de se mapear um par destes parâmetros para um espaço de maior significado psicoacústico<br>Mestrado<br>Eletrônica, Microeletrônica e Optoeletrônica<br>Mestre em Engenharia Elétrica
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Jumaat, M. Z. "The buckling behaviour of layered and spaced timber columns with interlayer slipping." Thesis, University of Southampton, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356527.
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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.
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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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Asbell, Jonathan Clark. "Thresholds in Space and Time." Thesis, Virginia Tech, 2020. http://hdl.handle.net/10919/100920.
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In architecture there is perhaps no better opportunity to capture movement and change than in the design of thresholds. They can be a simple strip of metal beneath a doorway, barely noticed as you pass over it, or a grand atrium that you stop and marvel at on your way into the office. They can manifest as a change of materials or finishes, or of some parameter such as ceiling height. They might even be immaterial altogether, like the boundary between light and shadow.
Thresholds transcend the physical to effect a psychological experience. They can be spatial or temporal or some combination of the two, but whatever form they take, all thresholds can be said to be mediators of our movement from one spatial status to another. Inside to outside, public to private, here to there. Too often our buildings relegate these changes to doors or openings that have little connection to the buildings they are a part of, and so our awareness of passage from space to space is diminished. This thesis explores ways to enrich the architecture of the threshold so that it doesn't merely recede to the bounds of our perception.<br>Master of Architecture<br>The term "threshold" often brings to mind a strip of material at the base of a doorway, but architecture considers thresholds more broadly as moments of movement or change. This thesis examines such moments in an original building design, proposing several threshold types and exploring their impact on occupants.
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Preston, Robert. "It´s All Relative: Time and Space in Nabokov´s Lolita." Thesis, Högskolan i Halmstad, Sektionen för humaniora (HUM), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-23349.
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This essay offers a deconstructive approach to Nabokov´s Lolita. Critics have tended to treat space and time as distinct concepts in the novel: choosing to analyse the role of either one or the other, and even when considering both, examining them in isolation. It´s narrator, Humbert Humbert, however, implies that "time" and "spatial" terms are interchangeable in a way reminiscent of Einstein´s Theory of Relativity in which space-time is a continuum that is experienced relative to the individual observer´s own position in the universe. This essay therefore explores the possibility that Nabokov may have used Einstein´s concept of space-time relativity as a metaphor in Lolita. The essay looks first at the various ways in which the idea of relativity surfaces throughout the novel not just in relation to space and time, but also in its moral, cultural and historic forms. The roles of the Hour Glass Lake, Lolita´s sunglasses and Humbert´s car, three of the novel´s chief symbols, are then discussed in relation to its key elements: the notion of time dilation, the place of the observer and Humbert´s space-time bubble. It next concentrates on how the characters in the novel exemplify the roles of both observer and observed in a modern, self-centred and morally relativistic world. The final section argues that Humbert’s "madness" represents the most extreme consequence of his living in his own solipsistic bubble of space-time, or "dream vacuum" as he calls it.
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Nheu, Anie Art College of Fine Arts UNSW. "At the periphery of space." Awarded by:University of New South Wales. Art, 2008. http://handle.unsw.edu.au/1959.4/43554.
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Mason, Lionel J. "Twistors in curved space time." Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:29de7cd1-84c9-4374-8f7d-9a402dd9e0ed.
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This thesis is concerned with an investigation of twistorial structures present in curved Lorentzian space-times. Chapter 1 introduces the basic definitions and some theorems that will be used later in the text. Chapter 2 investigates generalised connections that arise in twister theory. First the Cartan con-formal connection is studied, and some of the geometry underlying it is shown to be that used by Fefferman and Graham C133. Also a condition that a space-time is conformal to vacuum is given. Secondly the theory of the Chern connection associated to a C.R. manifold is developed in such a way as to make the calculation of the connection associated to a twistor C.R. manifold straight forward. A new proof of the Chern theorem of existence and uniqueness is given. The Chern connection of a twistor C.R. manifold is then calculated, and discussed. In particular S-dimensionai C.R. manifolds arising as twistor C.R. manifolds are characterised. Canonical structures peculiar to the twister case are discussed. Applications of C.R. manifold theory to algebraically special space-times are suggested. Chapter three analyses how various twistorial structures behave in linearised general relativity. First, deformations of the space of complex null geodesies corresponding to variations of the conformal structure of space-time are shown to be generated by hami1tonians. Those that correspond to variations in the metric satisfying the field equations are given, along with hamiltonians corresponding to different fields and field equations. Beneralisations to nonlinear equations are discussed. These ideas are applied to hypersurface twisters in linearised theory, using fiat hypersurfaces and Cech cohoeology. Expressions are obtained for the deformation of the complex structure of the spaces and their evolution. The results are generalised to non flat hypersurfaces using Dolbeault cohomolcgy. It is shown that certain canonically defined forms on the spin bundle are preferred Dolbeault representatives for derivatives of the twister cohomology classes corresponding to the linearised field. In chapter four I generalise the results of chapter three to curved space using the Chern connection. In particular twistorial formulations of the constraint equations are given, and a formula for the evolution that satisfies the the vacuum evolution equations is given in terms of an "infinity" twistor and a "time" twister. This is then discussed. In chapter five I make some comments on the interpretation of a three form on the spin bundle discovered by B.A.J. Sparling as the gravitational hami1tonian. I then use this to show that one can give an interpretation of Penrose's quasi-local angular momentum twistor in terms of the canonical formalism.
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dalton, timothy. "A Space for Absence." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/1660.
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This thesis focuses on the evolution of my work created during my two years of study at Virginia Commonwealth University. Although I touch upon my influences what I am writing is a reflection after the fact that does not necessarily encompass my original intent or inspirations for these works. I find my inspiration from personal discoveries within my daily life. Light flickering through the rails of a fence as I walk by makes me more aware of my body's movement in space. Watching the steady condensation of water droplets forming on a fountain creates a moment of pause within the world. Through these discoveries preconceptions about the world are forgotten and instead I focus on my experience. The potential for translating these moments into installations for an audience fuels my work. Though everyone experiences the world differently the pursuit of a common ground creates situations for further discoveries. The process of writing this paper has helped me to find a common thread within my work. Thinking back through the experiential discoveries of each piece has furthered my understanding, just as it originally propelled my artistic productio
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Parpoulova, Petia R. "Amalgamated spaces of modernity /." Thesis, Connect to this title online; UW restricted, 2008. http://hdl.handle.net/1773/6638.
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Acharya, Om Nath, and Sabin Upadhyaya. "Space Time Coding For Wireless Communication." Thesis, Linnéuniversitetet, Institutionen för datavetenskap, fysik och matematik, DFM, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-19424.
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As the demand of high data rate is increasing, a lot of research is being conducted in the field of wireless communication. A well-known channel coding technique called Space-Time Coding has been implemented in the wireless Communication systems using multiple antennas to ensure the high speed communication as well as reliability by exploiting limited spectrum and maintaining the power. In this thesis, Space-Time Coding is discussed along with other related topics with special focus on Alamouti Space-Time Block Code. The Alamouti Codes show good performance in terms of bit error rate over Rayleigh fading channel. The performance of Altamonte’s code and MIMO capacity is evaluated by using MATLAB simulation.
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Franzoni, Lorenzo. "Mechanical behavior of regularly spaced Cross Laminated Timber panels : Modeling and experimental validation in ambient and fire conditions." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1113/document.
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Les panneaux en bois lamellé croisé (en anglais CLT - Cross Laminated Timber) sont des éléments de structure composés de couches en bois collées entre eleese et empilées de façon croisée. Chaque couche est composée de planches en bois juxtaposées et généralement non collées sur leur chants. Dans cette thèse, nous étudions l'influence sur le comportement mécanique des espacements entre planches des panneaux avec une approche par modélisation et expérimentation. Les panneaux CLT standard sont considérés comme des panneaux avec des espacements de très faible dimension par opposition aux panneaux avec espacements importants que nous appelons panneaux innovants. Nous modélisons dans un premier temps le comportement en flexion de panneaux standard à l'aide d'un modèle de couche homogène équivalente basée sur des hypothèses simplifiées de la mécanique d'une couche avec chants collés ou non collés. Nous observons un bon accord entre les résultats de notre modélisation et des résultats expérimentaux issus de la littérature. Des études paramétriques sont ensuite réalisés portant sur certaines propriétés des panneaux.Nous avons ensuite réalisé des essais de flexion 4-points sur des panneaux CLT standard et innovants pour quantifier l'influence des espacements sur la réponse mécanique des panneaux. Il se trouve que l'influence des effets de cisaillement transverse sur le comportement élastique et à la rupture augmente avec l'augmentation des vides dans le panneau.Afin de prendre correctement en compte les effets du cisaillement, les CLT espacés sont modélisés comme des plaques épaisses périodiques à l'aide d'un modèle de plaque d'ordre supérieur. Ce modèle a été appliqué à la géométrie des panneaux CLT espacés avec un schéma d'homogénéisation périodique. Des méthodes simplifiées existantes ont également été comparées avec les résultats des essais et le modèle de plaque. De plus, des résultats d'essais de cisaillement dans le plan des panneaux CLT standard issus de la littérature ont été comparés avec nos résultats. La raideur de flexion des CLT espacés peut être prédite avec des méthodes simples existantes, alors que seule la modélisation que nous proposons permet de prédire le comportement en cisaillement transverse et dans le plan. Finalement, des formules analytiques ont été obtenues pour prédire le comportement élastique des CLT espacés. Ces formules donnent une bonne approximation u comportement des CLT espacés et peuvent être utilisées dans le cadre d'une démarche pratique de dimensionnement.Enfin, une étude concernant l'analyse du comportement au feu des panneaux CLT standard est présentée. La comparaison entre des résultats d'essais au feu et une modélisations avancée et simplifiée a permis de proposer une possible amélioration de la méthode de dimensionnement au feu standard<br>Cross Laminated Timber (CLT, or crosslam) panels are engineered timber products composed of layers made of wooden lamellas placed side by side, glued on their upperand lower faces and stacked crosswise. In the present thesis, the influence of lateral spaces between lamellas of each layer on the panel’s mechanical response is investigated with modeling and tests. Both configurations of standard panels having short spaces and innovative CLT panels with large spaces are analyzed.As a first approach, the bending behavior of standard crosslam was modeled by means of an equivalent-layer model based on simplified hypotheses on mechanical properties of laterally glued or unglued layers. The good agreement of the predicted behavior with an experiment of the literature finally allowed an investigation on several CLT properties by means of parameter studies.Then, 4-points bending tests on standard and innovative CLT floors were performed in order to quantify the influence of periodic spaces on the panels' mechanical response. It appears that the influence of transverse shear effects on the elastic and failure behavior of spaced CLT increases with the increasing spaces between boards.In order to take into account transverse shear effects, spaced CLT have been modeled as periodic thick plates by means of a higher-order plate theory for laminated plates. This model has been applied to the geometry of spaced CLT with a periodic homogenization scheme. Existing simplified methods for spaced crosslam were compared as well with refined modeling and test results. Moreover, available in-plane shear tests of the literature have been compared to the modeling results. It appears that the bending behavior of spaced CLT can be predicted with simplified existing approaches, while only the more refined modeling can predict the in-plane and transverse shear behavior. Then, closed-form solutions for predicting spaced CLT elastic behavior were derived in order to encourage the application of spaced CLT panels in modern timber construction.One further study within this thesis concerns the analysis of fire-exposed standard CLT floors. The comparison between test results and both advanced and simplified modeling led to a suggestion for a possible improvement the standard fire design model
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Al-Ghadhban, Samir Naser. "Multi-layered Space Frequency Time Codes." Diss., Virginia Tech, 2005. http://hdl.handle.net/10919/29498.
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This dissertation focuses on three major advances on multiple-input multiple-output (MIMO) systems. The first studies and compares decoding algorithms for multi-layered space time coded (MLSTC) systems. These are single user systems that combine spatial multiplexing and transmit diversity. Each layer consists of a space time code. The detection algorithms are based on multi-user detection theory. We consider joint, interference nulling and cancellation, and spatial sequence estimation algorithms. As part of joint detection algorithms, the sphere decoder is studied and its complexity is evaluated over MIMO channels. The second part contributes to the field of space frequency time (SFT) coding for MIMO-OFDM systems. It proposes a full spatial and frequency diversity codes at much lower number of trellis states. The third part proposes and compares uplink scheduling algorithms for multiuser systems with spatial multiplexing. Several scheduling criteria are examined and compared.
The capacity and error rate study of MLSTBC reveals the performance of the detection algorithms and their advantage over other open loop MIMO schemes. The results show that the nulling and cancellation operations limit the diversity of the system to the first detected layer in serial algorithms. For parallel algorithms, the diversity of the system is dominated by the performance after parallel nulling. Theoretically, parallel cancellation should provide full receive diversity per layer but error propagations as a result of cancellation prevent the system from reaching this goal. However, parallel cancellation provides some gains but it doesn't increase the diversity. On the other hand, joint detection provides full receive diversity per layer. It could be practically implemented with sphere decoding which has a cubic complexity at high SNR.
The results of the SFT coding show the superiority of the IQ-SFT codes over other codes at the same number of sates. The IQ-SFT codes achieve full spatial and frequency diversity at much lower number of trellis states compared to conventional codes. For V-BLAST scheduling, we propose V-BLAST capacity maximizing scheduler and we show that scheduling based on optimal MIMO capacity doesn't work well for V-BLAST. The results also show that maximum minimum singularvalue (MaxMinSV) scheduling performs very close to the V-BLAST capacity maximizing scheduler since it takes into account both the channel power and the orthogonality of the channel.<br>Ph. D.
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Jensen, Michael A., and Michael D. Rice. "SPACE-TIME CODING FOR WIRELESS COMMUNICATIONS." International Foundation for Telemetering, 2002. http://hdl.handle.net/10150/605605.
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International Telemetering Conference Proceedings / October 21, 2002 / Town & Country Hotel and Conference Center, San Diego, California<br>Signal fading and intersymbol interference created by multipath propagation have traditionally
limited the throughput on wireless communications systems. However, recent research has
demonstrated that by using multiple antennas on both transmit and receive ends of the link, the
multipath channel can actually be exploited to achieve increased communication throughput over
single-antenna systems. This paper provides an introductory description of such multi-antenna
communications systems, focusing on basic explanations of how they achieve capacity gains.
Computed and measured capacity results are used to demonstrate the potential of these systems.
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Karacayir, Murat. "Space-time Codes." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612028/index.pdf.
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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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Rivera, Monica Alexandra. "Slowing Down Time, studies on spatial time." Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/33992.
Full textAbstract:
The experience of time is not fixed by a rigid mathematical measure, instead, it flows at vaying rates.
There are certain occasions in which we would like to extend time with all our force, up to the limit of our stretched arms and further. Conversely there are moments which we'd like to last no more that the sparkle of a flash, but as we all have noticed, those are the longest in our life.
How does the space that we inhabit influence on our perception of time? May we identify especial elements that contribute in one or other sense to accelerate or slowdown the time?
It's said that time and space is an inseparable unity, as two aspects of the same thing. If this is so, then it also must be true that by shaping space in one way or another, we might influence the experience of time through it. Wouldn't it be delightful to believe that we may be magicians of time through manipulation of architecture?<br>Master of Architecture
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Fan, Junchuan. "Modeling space-time activities and places for a smart space —a semantic approach." Diss., University of Iowa, 2017. https://ir.uiowa.edu/etd/5752.
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The rapid advancement of information and communication technologies (ICT) has dramatically changed the way people conduct daily activities. One of the reasons for such advances is the pervasiveness of location-aware devices, and people’s ability to publish and receive information about their surrounding environment. The organization, integration, and analysis of these crowdsensed geographic information is an important task for GIScience research, especially for better understanding place characteristics as well as human activities and movement dynamics in different spaces. In this dissertation research, a semantic modeling and analytic framework based on semantic web technologies is designed to handle information related with human space-time activities (e.g., information about human activities, movement, and surrounding places) for a smart space. Domain ontology for space-time activities and places that captures the essential entities in a spatial domain, and the relationships among them. Based on the developed domain ontology, a Resource Description Framework (RDF) data model is proposed that integrates spatial, temporal and semantic dimensions of space-time activities and places. Three different types of scheduled space-time activities (SXTF, SFTX, SXTX) and their potential spatiotemporal interactions are formalized with OWL and SWRL rules. Using a university campus as an example spatial domain, a RDF knowledgebase is created that integrates scheduled course activities and tweet activities in the campus area. Human movement dynamics for the campus area is analyzed from spatial, temporal, and people’s perspectives using semantic query approach. The ontological knowledge in RDF knowledgebase is further fused with place affordance knowledge learned through training deep learning model on place review data. The integration of place affordance knowledge with people’s intended activities allows the semantic analytic framework to make more personalized location recommendations for people’s daily activities.
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Kennedy, Ashley B. "Time-Space: Constructing Meaning Through Temporal Phenomena." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/19231.
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This thesis is an examination of the significance of time and temporal phenomena in the conception and construction of the built environment. It began as a question regarding the aging and life-span of contemporary buildings, in contrast with those that have at present survived long enough to earn designation as \'historic\' buildings.<br /><br />The term \'temporal phenomena\' is defined here as sensory experiences which make the passage of time accessible and meaningful to those interacting with the built environment.<br /><br />Le Corbusier wrote that an original intent of painting was to record, to create permanent evidence of events and things that passed away with time and were forgotten, or couldn\'t be seen later. He suggests that the camera is a much better tool for this, and so painting has lost part of its purpose. Buildings and cities have always had the effect of retaining memory and creating cultural meanings. Cultural reliance on continuous improvements in environmental and building technologies have obviated the building\'s ancient place as a datum through which human beings understand the passage of time. And perhaps it is the loss of that sacred duty that leads to short-lived, disposable buildings, and the proliferation of placeless-ness in contemporary environments.<br /><br />A design for a brewery on the banks of the Potomac River in Alexandria, Virginia became the vehicle to explore strategies for making time meaningful and present through the physical reality of the building, the brewing process, and the interrelated lives of the brewer and the city.<br>Master of Architecture
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Nakagawa, Yoshito. "Deliberative peacebuilding in East Timor and Somaliland." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/deliberative-peacebuilding-in-east-timor-and-somaliland(86fa6d48-7993-4b91-b71e-bcc5ce630d92).html.
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This thesis is a theoretical and empirical inquiry into ‘deliberative peacebuilding’, seeking to explain the ‘failures’ and ‘successes’ of peacebuilding in East Timor and Somaliland. While warfare has increased globally since the end of the Cold War, the UN has made efforts to build peace (e.g. Boutros-Ghali 1992). While peacebuilding has become an internationally applied set of ideas and practices, one of the theoretical gaps is deliberation. This research thus conceptualises ‘deliberative peacebuilding’, and associates this with peacebuilding in the non-Western, post-colonial, and (post-)conflict context. This research identified East Timor and Somaliland as its case studies. Despite similarity in the ‘legitimation problem’ with vertical (state-society) and horizontal (‘modernity’-‘tradition’) inequalities/differences based upon cultural and historical backgrounds, East Timor and Somaliland undertook different approaches in a decade after the end of their civil wars. While East Timor accepted UN peace operations, Somaliland rejected them. Yet both experienced similar transitions to make political order between ‘failure’ (political de-legitimation/societal dissent) and ‘success’ (political legitimation/societal consent).Accordingly, this thesis poses two questions: 1) what caused the UN to have ‘failed’ (to prevent the ‘crisis’ from recurring in 2006) in East Timor, and 2) what caused East Timor and Somaliland to have experienced ‘equifinality’ (making similar progress along different paths) in building peace (in East Timor from 1999 to 2012 and in Somaliland from 1991 to 2005). Findings, among others, include different paths in transition: a ‘hybrid’ path with external intervention in East Timor and an ‘agonistic’ path without it in Somaliland. Asymmetry in power relations urged deliberative agencies to address the ‘legitimation problem’ differently.
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Wilson, Daniel. "Local time-space calculus with applications." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/local-timespace-calculus-with-applications(f04e32e3-4c9b-4348-a7f3-803dee125e43).html.
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Taylor, David Preston Landini Gregory. "Structure and transition towards an accretivist theory of time /." Iowa City : University of Iowa, 2009. http://ir.uiowa.edu/etd/443.
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Muratore, John F. "Trends in Space Shuttle Telemetry Applications." International Foundation for Telemetering, 1987. http://hdl.handle.net/10150/615327.
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International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California<br>During early manned spacecraft operations, the primary role of ground telemetry systems was data display to flight controllers. As manned spaceflights have increased in complexity, greater demands have been placed on flight controllers to simultaneously monitor systems and replan systems operations. This has led to interest in automated telemetry monitoring systems to decrease the workload on flight controllers. The Mission Operations Directorate at the Lyndon B. Johnson Space Center has developed a five layer model to integrate various monitoring and analysis technologies such as digital filtering, fault detection algorithms, and expert systems. The paper describes the five layer model and explains how it has been used to guide prototyping efforts at Mission Control. Results from some initial expert systems are presented. The paper also describes the integrated prototype currently under development which implements a real time expert system to assist flight controllers in the Mission Control Center in monitoring Space Shuttle communications systems.
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Masoud, Masoud. "Space-time block coding for wireless communications." Thesis, University of Hertfordshire, 2008. http://hdl.handle.net/2299/2548.
Full textAbstract:
Wireless designers constantly seek to improve the spectrum efficiency/capacity, coverage of wireless networks, and link reliability. Space-time wireless technology that uses multiple antennas along with appropriate signalling and receiver techniques offers a powerful tool for improving wireless performance. Some aspects of this technology have already been incorporated into various wireless network and cellular mobile standards. More advanced MIMO techniques are planned for future mobile networks, wireless local area network (LANs) and wide area network (WANs). Multiple antennas when used with appropriate space-time coding (STC) techniques can achieve huge performance gains in multipath fading wireless links. The fundamentals of space-time coding were established in the context of space-time Trellis coding by Tarokh, Seshadri and Calderbank. Alamouti then proposed a simple transmit diversity coding scheme and based on this scheme, general space-time block codes were further introduced by Tarokh, Jafarkhani and Calderbank. Since then space-time coding has soon evolved into a most vibrant research area in wireless communications. Recently, space-time block coding has been adopted in the third generation mobile communication standard which aims to deliver true multimedia capability. Space-time block codes have a most attractive feature of the linear decoding/detection algorithms and thus become the most popular among different STC techniques. The decoding of space-time block codes, however, requires knowledge of channels at the receiver and in most publications, channel parameters are assumed known, which is not practical due to the changing channel conditions in real communication systems. This thesis is mainly concerned with space-time block codes and their performances. The focus is on signal detection and channel estimation for wireless communication systems using space-time block codes. We first present the required background materials, discuss different implementations of space-time block codes using different numbers of transmit and receive antennas, and evaluate the performances of space-time block codes using binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), and quadrature amplitude modulation (QAM). Then, we investigate Tarokh’s joint detection scheme with no channel state information thoroughly, and also propose a new general joint channel estimation and data detection scheme that works with QPSK and 16-QAM and different numbers of antennas. Next, we further study Yang’s channel estimation scheme, and expand this channel estimation scheme to work with 16-QAM modulation. After dealing with complex signal constellations, we subsequently develop the equations and algorithms of both channel estimation schemes to further test their performances when real signals are used (BPSK modulation). Then, we simulate and compare the performances of the two new channel estimation schemes when employing different number of transmit and receive antennas and when employing different modulation methods. Finally, conclusions are drawn and further research areas are discussed.
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Shaw, Kwok-wah Roddy, and 邵國華. "Gay desire and the politics of space." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31953700.
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Kitchingham, David William. "Generating techniques in vacuum and stiff perfect fluid cosmologies." Thesis, Queen Mary, University of London, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337947.
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Primorac, Ranka. "Displacement, identity and fictional formation in selected recent Zimbabwean novels." Thesis, Nottingham Trent University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271213.
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Gu, Yu. "Noncoherent communications using space-time trellis codes." Thesis, University of Canterbury. Electrical and Computer Engineering, 2008. http://hdl.handle.net/10092/1252.
Full textAbstract:
In the last decade much interest has been shown in space-time trellis codes (STTCs) since they can offer coding gain along with the ability to exploit the space and time diversity of MIMO channels. STTCs can be flexibly designed by trading off performance versus complexity. The work of Dayal [1] stated that if training symbols are used together with data symbols, then a space-time code can be viewed as a noncoherent code. The authors of [1] described the migration from coherent space-time codes to training assisted noncoherent space-time codes. This work focuses on the development of training assisted noncoherent STTCs, thus extending the concept of noncoherent training codes to STTCs. We investigate the intrinsic link between coherent and noncoherent demod- ulation. By analyzing noncoherent STTCs for up to four transmit antennas, we see that they have similar performance deterioration to noncoherently demodulated M-PSK using a single antenna. Various simulations have been done to confirm the analysis.
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Wang, Jibing, Kung Yao, and Don Whiteman. "Space-Time Coding for Avionic Telemetry Channels." International Foundation for Telemetering, 2003. http://hdl.handle.net/10150/607482.
Full textAbstract:
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada<br>Multiple antennas promise high data capacity for wireless communications. Most space-time coding schemes in literature focus on the rich scatter environment. In this paper, we argue that minimax criterion is a good design criterion for space-time codes over the avionic telemetry channels. This design criterion is different than those of space-time codes over rich scattering Rayleigh fading channels. Theoretical and numerical results show that the codes with optimal performance in Rayleigh fading channels do not necessarily have optimal performance in avionic telemetry channels. Therefore, the space-time codes should be carefully designed/selected when used in the avionic telemetry channels.
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Delestre, Fabien. "Channel estimation and performance analysis of MIMO-OFDM communications using space-time and space-frequency coding schemes." Thesis, University of Hertfordshire, 2011. http://hdl.handle.net/2299/6397.
Full textAbstract:
This thesis is concerned with channel estimation and data detection of MIMO-OFDM communication systems using Space-Time Block Coding (STBC) and Space-Frequency Block Coding (SFBC) under frequency selective channels. A new iterative joint channel estimation and signal detection technique for both STBC-OFDM and SFBC-OFDM systems is proposed. The proposed algorithm is based on a processive sequence of events for space time and space frequency coding schemes where pilot subcarriers are used for channel estimation in the first time instant, and then in the second time instant, the estimated channel is used to decode the data symbols in the adjacent data subcarriers. Once data symbols are recovered, the system recursively performs a new channel estimation using the decoded data symbols as pilots. The iterative process is repeated until all MIMO-OFDM symbols are recovered. In addition, the proposed channel estimation technique is based on the maximum likelihood (ML) approach which offers linearity and simplicity of implementation. Due to the orthogonality of STBC and SFBC, high computation efficiency is achieved since the method does not require any matrix inversion for estimation and detection at the receiver. Another major novel contribution of the thesis is the proposal of a new group decoding method that reduces the processing time significantly via the use of sub-carrier grouping for transmitted data recovery. The OFDM symbols are divided into groups to which a set of pilot subcarriers are assigned and used to initiate the channel estimation process. Designated data symbols contained within each group of the OFDM symbols are decoded simultaneously in order to improve the decoding duration. Finally, a new mixed STBC and SFBC channel estimation and data detection technique with a joint iterative scheme and a group decoding method is proposed. In this technique, STBC and SFBC are used for pilot and data subcarriers alternatively, forming the different combinations of STBC/SFBC and SFBC/STBC. All channel estimation and data detection methods for different MIMO-OFDM systems proposed in the thesis have been simulated extensively in many different scenarios and their performances have been verified fully.
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Nordin, Astrid. "Time, space and multiplicity in China's harmonious world." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/time-space-and-multiplicity-in-chinas-harmonious-world(3cdd05ec-8525-47bc-93e1-3693feaff778).html.
Full textAbstract:
Multiplicity is a key challenge and opportunity of world politics, yet scholars continue to struggle to do it justice. One way of reducing the challenge multiple times and spaces present us with has been to organise them allochronically, to align spatial difference in temporal sequence. The effect is a story where others are not different, they are just behind. Scholars have criticised this thinking as it appears in “Western thought”. In recent years, suggestions have emerged that Chinese thought may offer an alternative that escapes allochronic thinking, most notably through the foreign policy-driven concept “harmonious world”. Scholars have studied this term with the aim of finding out its true meaning. This thesis asks instead what “harmony” – and more specifically “harmonious world” – does when it is deployed in contemporary China. It traces the concept across several contexts: the policy documents and speeches that launched it as an official term; the academic literatures that asked what a harmonious world might look like; the propaganda at Expo 2010 Shanghai China that aimed to illustrate it; and the online spoofing culture egao that was used to criticise, resist and avoid “harmonisation”.The key claim of this thesis is that “harmonious world”, as articulated in the contexts examined here, has not taken place, is not taking place and will not take place. Ways of thinking about time, space and multiplicity in China’s relation to the world, and particularly “harmonious world”, repeat the allochronising logic recognisable from “Western” discourses, which disallows the openness of the future and reduces the possibilities of harmony and of the political. As an effect of its excessive proliferation harmony disappears as an imagined metaphysical possibility . The harmonious system is not based on co-operation or non co-operation, but works according to what this thesis calls an onco-operative logic: the quasi-suicidal logic of cancer and the (auto)immune. Ultimately, the aim and most important contribution of this thesis is to bring the onco-operative uncertainty of the political back into the harmonious world concept in order to elucidate the negotiation of danger and necessity of multiplicity.
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Van, Wyk Daniel Jacobus. "Space-time turbo coding for CDMA mobile communications." Pretoria : [s.n.], 2000. http://upetd.up.ac.za/thesis/available/etd-01172007-112643/.
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Maw, Rachel Leigh. "Space-time Coded Systems with Continuous Phase Modulation." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1185.
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Space-time coded systems developed in the last ten years have been designed primarily using linear modulation. Non-linear continuous phase modulation has desirable constant envelope properties and considerable potential in space-time coded systems. The work in this thesis is focussed on developing and analysing an integrated space-time coded continuous phase modulated (STC-CPM) system. The coding of the space-time encoder and the modulation is incorporated into a single trellis encoder. This allows state combining, which leads to complexity reduction due to the reduced number of states. Design criteria for STC-CPM are summarized and the Euclidean distance is shown to be important for code design. The integrated STC-CPM system design enables systematic spacetime code searches that find optimal space-time codes, to be easily implemented. Optimal rate-1/2 and rate-2/3 space-time codes are found by maximizing the system's minimum squared Euclidean distance. These codes can provide high throughput and good coding gains over un-optimized full rank codes, such as delay diversity, in a quasi-static flat fading environment. Performance bounds are developed using a union bound argument and the pairwise error probability. Approximations of the bounds are evaluated. These truncated upper bounds predict the slopes of the simulated performance curves at low error rates.
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Shah, Musawir. "IMAGE-SPACE APPROACH TO REAL-TIME REALISTIC RENDERING." Doctoral diss., University of Central Florida, 2007. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3245.
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One of the main goals of computer graphics is the fast synthesis of photorealistic image of virtual 3D scenes. The work presented in this thesis addresses this goal of speed and realism. In real-time realistic rendering, we encounter certain problems that are difficult to solve in the traditional 3-dimensional geometric space. We show that using an image-space approach can provide effective solutions to these problems. Unlike geometric space algorithms that operate on 3D primitives such as points, edges, and polygons, image-space algorithms operate on 2D snapshot images of the 3D geometric data. Operating in image-space effectively decouples the geometric complexity of the 3D data from the run-time of the rendering algorithm. Other important advantages of image-space algorithms include ease of implementation on modern graphics hardware, and fast computation of approximate solutions to certain lighting calculations. We have applied the image-space approach and developed algorithms for three prominent problems in real-time realistic rendering, namely, representing and lighting large 3D scenes in the context of grass rendering, rendering caustics, which is a complex indirect illumination effect, and subsurface scattering for rendering of translucent objects.<br>Ph.D.<br>School of Electrical Engineering and Computer Science<br>Engineering and Computer Science<br>Computer Science PhD
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Granados, Omar D. "Space-Time Coding for Polynomial Phase Modulated Signals." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/378.
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Polynomial phase modulated (PPM) signals have been shown to provide improved error rate performance with respect to conventional modulation formats under additive white Gaussian noise and fading channels in single-input single-output (SISO) communication systems. In this dissertation, systems with two and four transmit antennas using PPM signals were presented. In both cases we employed full-rate space-time block codes in order to take advantage of the multipath channel. For two transmit antennas, we used the orthogonal space-time block code (OSTBC) proposed by Alamouti and performed symbol-wise decoding by estimating the phase coefficients of the PPM signal using three different methods: maximum-likelihood (ML), sub-optimal ML (S-ML) and the high-order ambiguity function (HAF). In the case of four transmit antennas, we used the full-rate quasi-OSTBC (QOSTBC) proposed by Jafarkhani. However, in order to ensure the best error rate performance, PPM signals were selected such as to maximize the QOSTBC’s minimum coding gain distance (CGD). Since this method does not always provide a unique solution, an additional criterion known as maximum channel interference coefficient (CIC) was proposed. Through Monte Carlo simulations it was shown that by using QOSTBCs along with the properly selected PPM constellations based on the CGD and CIC criteria, full diversity in flat fading channels and thus, low BER at high signal-to-noise ratios (SNR) can be ensured. Lastly, the performance of symbol-wise decoding for QOSTBCs was evaluated. In this case a quasi zero-forcing method was used to decouple the received signal and it was shown that although this technique reduces the decoding complexity of the system, there is a penalty to be paid in terms of error rate performance at high SNRs.
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Yoon, Chun Suk. "Ministry strategy in a cyber age change from visual education to auditory one." Online full text .pdf document, available to Fuller patrons only, 2003. http://www.tren.com.
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Nguyen, Anh Van. "Concatenated space-time coding for wireless systems." Diss., Georgia Institute of Technology, 2002. http://hdl.handle.net/1853/13533.
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Guimond, David. "(Re)sounding : disintegrating visual space in music." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102803.
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While the groundbreaking insights that contemporary theorists have formulated with regards to space---as a multiplicity without essence, as an active event, and as inseparable from subjectivity, power, Otherness and time---have ostensibly purged it of its traditional understanding as absolute, a specific visuality characteristic of Cartesian perspectivalism remains privileged in its theorization which force it to remain so. While the complexity of space cannot be recovered from an abstract contemplation of its visual geometry in a way that reflects these contemporary concerns, there have unfortunately been relatively few attempts to imagine space away from the visual in a way that challenges its traditional absoluteness. To this end, it is argued that because sound and music contain implicit and explicit spatialities, the sonic represents a rich and unexplored area from which to imagine a radical non-visual space that discursively organizes space according to a different economy through which to challenge its assumed visuality. And yet, even when space has been approached through sound, there is a tendency to exteriorize sound into an object or a set of practices that robs it of its defining quality---its own "soundfulness". By breaking down those factors that are considered salient to how space is conceived today along sonic rather than visual lines, the argument is made that the "soundfulness" of sound's physical properties gives it a complex texture of excess that is corporealized within the body and forwards the philosophical possibility of unfolding the spatiality of sound according to vectors beyond the visible in a way that, while reflecting contemporary concerns, prevents its return to absoluteness. To take seriously this "soundfulness" thus allows us to recuperate the sonic as a philosophical and political way of experiencing and knowing the world, including that of space. The arguments, as well as being drawn from the insights of contemporary spatial theory, the physics of sound, the phenomenology of listening, rhizomatic and feminist theory, quantum mechanics and musicology, will be explained through an understanding of space as sound and exemplified in The Disintegration Loops, a post-minimalist musical piece by sonic artist William Basinski.
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Shaw, Kwok-wah Roddy. "Gay desire and the politics of space." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B2526235x.
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Manuel, Kwok Keung Kevin. "Redevelopment and urban space and form : Times Square Precinct /." Hong Kong : University of Hong Kong, 1995. http://sunzi.lib.hku.hk/hkuto/record.jsp?B14804189.
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Kuronen, Suzanne. "Figuring space : considering the figure in the construction of space as materialist film." University of Western Australia. School of Architecture, Landscape and Visual Arts, 2004. http://theses.library.uwa.edu.au/adt-WU2005.0015.
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Figuring Space; considering the figure in the construction of space in materialist film is an analysis of film space that uses either the image of a figure or the actual figure of the viewer in its construction. The thesis focuses on particular screen works of William Raban, Guy Sherwin, Malcolm Le Grice, Chris Welsby, Nicky Hamlyn, Peter Gidal (all members of the London Filmmakers’ Cooperative) and the Canadian artist Michael Snow. It discusses the works in relation to the basic materials of time, light and sound found in film and video. The thesis looks at the way the film frame was implemented in the work of these artists to challenge preconceived notions of film space. It also highlights the uncertainty of spatial relativity within the screen image once the techniques imposed by the artist undermine previous determinations of positions in space. The frame provides necessary elements with which a reading of a pictorial space can be made. In addition, with some of the works discussed, the frame defines an exterior screen space that at times questions the boundaries between on-screen and off-screen, and fictive space and real space. While in other works that are addressed, binaries exist within which the boundaries of a picture plane are utilized to determine an object’s spatial relativity, which in turn questions the relativity of those boundaries that determine it. The frame that previously confirmed the illusions of space within the pictorial plane could no longer be prescribed as definitive. Calculations of the film space would become dependent upon a point of origin that is situated within actual time and space at the position of the viewer. The figure of paramount importance, when considering the constructs of space within materialist film, is that of the viewer
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Drake, George A. "Historical space in the eighteenth-century novel /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/9425.
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Elmabrouk, T. "Visualizing light cones in space-time." Thesis, Coventry University, 2013. http://curve.coventry.ac.uk/open/items/2d7e9956-f278-475c-b230-5a7a9dd08647/1.
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Although introductory courses in special relativity give an introduction to the causal structure of Minkowski space, it is common for causal structure in general space- times to be regarded as an advanced topic, and omitted from introductory courses in general relativity, although the related topic of gravitational lensing is often included. Here a numerical approach to visualizing the light cones in exterior Schwarzschild space taking advantage of the symmetries of Schwarzschild space and the conformal invariance of null geodesics is formulated, and used to make some of these ideas more accessible. By means of the Matlab software developed, a user is able to produce figures showing how light cones develop in Schwarzschild space, starting from an arbitrary point and developing for any length of time. The user can then interact with the figure, changing their point of view, or zooming in or out, to investigate them. This approach is then generalised, using the symbolic manipulation facility of Matlab, to allow the user to specify a metric as well as an initial point and time of development. Finally, the software is demonstrated with a selection of metrics.
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Wells, Olga V. "Time and space as artistic conventions in Chekhov and Dostoyevsky." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4307.
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Thesis (M.A.)--University of Missouri-Columbia, 2005.<br>The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (month day, year) Includes bibliographical references.
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Tonkin, Christopher Tonkin Christopher Tonkin Christopher. "Compositional metaphors of space and perspective /." Diss., Connect to a 24 p. preview or request complete full text in PDF formate. Access restricted to UC campuses, 2007. http://wwwlib.umi.com/cr/ucsd/fullcit?p3266845.
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Thesis (Ph. D.)--University of California, San Diego, 2007.<br>Vita. Discusses the composer's use of the metaphors of space and perspective in his works, IN and Headspaces, the scores for which are included in the dissertation.
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Kubík, Michal. "Magnetorheological Suspension Damper for Space Application." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2018. http://www.nusl.cz/ntk/nusl-371779.
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Disertační se práce se zabývala vývojem magnetoreologického (MR) tlumiče odpružení pro kosmonautiku. Dle současného stavu poznání jsou důležitými parametry pro semi-aktivně řízený tlumič pro kosmonautiku hermetické oddělení pracovní kapaliny od zbytku nosiče a krátká časová odezva tlumícího elementu. Těmto požadavkům vyhovuje magnetoreologický tlumič s vlnovcovou jednotkou. Magnetický obvod MR tlumiče pro kosmonautiku byl vyroben z feritového materiálu, který umožnil výrazně snížit časovou odezvu. Hermetičnost byla zajištěna použitím vlnovcové jednotky. Konstrukce takového typu tlumiče ovšem přináší celou řadu problémů. Vyvinutý MR tlumič s feritovým magnetickým obvodem dosahoval časové odezvy 4.1 ms a dynamického rozsahu 8. Během konstrukčních prací na MR tlumiči pro kosmonautiku byly hledány nové metody pro konstrukci semi-aktivně řízeného MR tlumiče s krátkou časovou odezvou. Konkrétně se jednalo o metodu eliminace vířivých proudů v magnetickém obvodu MR tlumiče, magnetostatický a transietní magnetický model, CFD model obtokové štěrbiny, hydraulický model MR tlumiče a jejich experimentální verifikace. Tyto nové metody umožní konstrukci MR tlumiče pro kosmonautiku lehčí, s nižší časovou odezvou a vyšším dynamickým rozsahem.
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Zhang, Zhi. "Error-rate evaluation and optimization for space-time codes." Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/hkuto/record/B39634218.
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