909 resultados para Panoramic projections. Virtual Environments. Navigation in 3D environments. Virtual Reality


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Improving the appearance of the trunk is an important goal of scoliosis surgical treatment, mainly in patients' eyes. Unfortunately, existing methods for assessing postoperative trunk appearance are rather subjective as they rely on a qualitative evaluation of the trunk shape. In this paper, an objective method is proposed to quantify the changes in trunk shape after surgery. Using a non-invasive optical system, the whole trunk surface is acquired and reconstructed in 3D. Trunk shape is described by two functional measurements spanning the trunk length: the lateral deviation and the axial rotation. To measure the pre and postoperative differences, a correction rate is computed for both measurements. On a cohort of 36 scoliosis patients with the same spinal curve type who underwent the same surgical approach, surgery achieved a very good correction of the lateral trunk deviation (median correction of 76%) and a poor to moderate correction of the back axial rotation (median correction of 19%). These results demonstrate that after surgery, patients are still confronted with residual trunk deformity, mainly a persisting hump on the back. That can be explained by the fact that current scoliosis assessment and treatment planning are based solely on radiographic measures of the spinal deformity and do not take trunk deformity into consideration. It is believed that with our novel quantitative trunk shape descriptor, clinicians and surgeons can now objectively assess trunk deformity and postoperative shape and propose new treatment strategies that could better address patients' concern about their appearance. © (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

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Information display technology is a rapidly growing research and development field. Using state-of-the-art technology, optical resolution can be increased dramatically by organic light-emitting diode - since the light emitting layer is very thin, under 100nm. The main question is what pixel size is achievable technologically? The next generation of display will considers three-dimensional image display. In 2D , one is considering vertical and horizontal resolutions. In 3D or holographic images, there is another dimension – depth. The major requirement is the high resolution horizontal dimension in order to sustain the third dimension using special lenticular glass or barrier masks, separate views for each eye. The high-resolution 3D display offers hundreds of more different views of objects or landscape. OLEDs have potential to be a key technology for information displays in the future. The display technology presented in this work promises to bring into use bright colour 3D flat panel displays in a unique way. Unlike the conventional TFT matrix, OLED displays have constant brightness and colour, independent from the viewing angle i.e. the observer's position in front of the screen. A sandwich (just 0.1 micron thick) of organic thin films between two conductors makes an OLE Display device. These special materials are named electroluminescent organic semi-conductors (or organic photoconductors (OPC )). When electrical current is applied, a bright light is emitted (electrophosphorescence) from the formed Organic Light-Emitting Diode. Usually for OLED an ITO layer is used as a transparent electrode. Such types of displays were the first for volume manufacture and only a few products are available in the market at present. The key challenges that OLED technology faces in the application areas are: producing high-quality white light achieving low manufacturing costs increasing efficiency and lifetime at high brightness. Looking towards the future, by combining OLED with specially constructed surface lenses and proper image management software it will be possible to achieve 3D images.

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The magnetic properties and interactions between transition metal (TM) impurities and clusters in low-dimensional metallic hosts are studied using a first principles theoretical method. In the first part of this work, the effect of magnetic order in 3d-5d systems is addressed from the perspective of its influence on the enhancement of the magnetic anisotropy energy (MAE). In the second part, the possibility of using external electric fields (EFs) to control the magnetic properties and interactions between nanoparticles deposited at noble metal surfaces is investigated. The influence of 3d composition and magnetic order on the spin polarization of the substrate and its consequences on the MAE are analyzed for the case of 3d impurities in one- and two-dimensional polarizable hosts. It is shown that the MAE and easy- axis of monoatomic free standing 3d-Pt wires is mainly determined by the atomic spin-orbit (SO) coupling contributions. The competition between ferromagnetic (FM) and antiferromagnetic (AF) order in FePtn wires is studied in detail for n=1-4 as a function of the relative position between Fe atoms. Our results show an oscillatory behavior of the magnetic polarization of Pt atoms as a function of their distance from the magnetic impurities, which can be correlated to a long-ranged magnetic coupling of the Fe atoms. Exceptionally large variations of the induced spin and orbital moments at the Pt atoms are found as a function of concentration and magnetic order. Along with a violation of the third Hund’s rule at the Fe sites, these variations result in a non trivial behavior of the MAE. In the case of TM impurities and dimers at the Cu(111), the effects of surface charging and applied EFs on the magnetic properties and substrate-mediated magnetic interactions have been investigated. The modifications of the surface electronic structure, impurity local moments and magnetic exchange coupling as a result of the EF-induced metallic screening and charge rearrangements are analysed. In a first study, the properties of surface substitutional Co and Fe impurities are investigated as a function of the external charge per surface atom q. At large inter-impurity distances the effective magnetic exchange coupling ∆E between impurities shows RKKY-like oscillations as a function of the distance which are not significantly affected by the considered values of q. For distances r < 10 Å, important modifications in the magnitude of ∆E, involving changes from FM to AF coupling, are found depending non-monotonously on the value and polarity of q. The interaction energies are analysed from a local perspective. In a second study, the interplay between external EF effects, internal magnetic order and substrate-mediated magnetic coupling has been investigated for Mn dimers on Cu(111). Our calculations show that EF (∼ 1eV/Å) can induce a switching from AF to FM ground-state magnetic order within single Mn dimers. The relative coupling between a pair of dimers also shows RKKY-like oscillations as a function of the inter-dimer distance. Their effective magnetic exchange interaction is found to depend significantly on the magnetic order within the Mn dimers and on their relative orientation on the surface. The dependence of the substrate-mediated interaction on the magnetic state of the dimers is qualitatively explained in terms of the differences in the scattering of surface electrons. At short inter-dimer distances, the ground-state configuration is determined by an interplay between exchange interactions and EF effects. These results demonstrate that external surface charging and applied EFs offer remarkable possibilities of manipulating the sign and strength of the magnetic coupling of surface supported nanoparticles.

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The conceptual component of this work is about "reference surfaces'' which are the dual of reference frames often used for shape representation purposes. The theoretical component of this work involves the question of whether one can find a unique (and simple) mapping that aligns two arbitrary perspective views of an opaque textured quadric surface in 3D, given (i) few corresponding points in the two views, or (ii) the outline conic of the surface in one view (only) and few corresponding points in the two views. The practical component of this work is concerned with applying the theoretical results as tools for the task of achieving full correspondence between views of arbitrary objects.

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The statistical analysis of compositional data should be treated using logratios of parts, which are difficult to use correctly in standard statistical packages. For this reason a freeware package, named CoDaPack was created. This software implements most of the basic statistical methods suitable for compositional data. In this paper we describe the new version of the package that now is called CoDaPack3D. It is developed in Visual Basic for applications (associated with Excel©), Visual Basic and Open GL, and it is oriented towards users with a minimum knowledge of computers with the aim at being simple and easy to use. This new version includes new graphical output in 2D and 3D. These outputs could be zoomed and, in 3D, rotated. Also a customization menu is included and outputs could be saved in jpeg format. Also this new version includes an interactive help and all dialog windows have been improved in order to facilitate its use. To use CoDaPack one has to access Excel© and introduce the data in a standard spreadsheet. These should be organized as a matrix where Excel© rows correspond to the observations and columns to the parts. The user executes macros that return numerical or graphical results. There are two kinds of numerical results: new variables and descriptive statistics, and both appear on the same sheet. Graphical output appears in independent windows. In the present version there are 8 menus, with a total of 38 submenus which, after some dialogue, directly call the corresponding macro. The dialogues ask the user to input variables and further parameters needed, as well as where to put these results. The web site http://ima.udg.es/CoDaPack contains this freeware package and only Microsoft Excel© under Microsoft Windows© is required to run the software. Kew words: Compositional data Analysis, Software

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When discussing the traditional and new missions of higher education (1996 Report to UNESCO of the International Commission on Education for the 21st Century) Jacques Delors stated that "Excessive attraction to social sciences has broken equilibrium of available graduates for workforce, thus causing doubts of graduates and employers on the quality of knowledge provided by higher education". Likewise, when discussing the progress of science and technology, the 1998 UNESCO World Conference on Higher Education concluded that "Another challenge concerts the latest advancements of Science, the sine qua non of sustainable development"; and that “with Information Technology, the unavoidable invasion of virtual reality has increased the distance between industrial and developing countries". Recreational Science has a long tradition all over the Educational World; it aims to show the basic aspects of Science, aims to entertain, and aims to induce thinking. Until a few years ago, this field of knowledge consisted of a few books, a few kits and other classical (yet innovative) ways to popularize the knowledge of Nature and the laws governing it. In Spain, the interest for recreational science has increased in the last years. First, new recreational books are being published and found in bookstores. Second the number of Science-related museums and exhibits is increasing. And third, new television shows are produced and new short science-based, superficial sketches are found in variety programs. However, actual programs in Spanish television dealing seriously with Science are scarce. Recreational Science, especially that related to physical phenomena like light or motion, is generally found at Science Museums because special equipment is required. On the contrary, Science related mathematics, quizzes and puzzles use to gather into books, e.g. the extensive collections by Martin Gardner. However, lately Science podcasts have entered the field of science communication. Not only traditional science journals and television channels are providing audio and video podcasts, but new websites deal exclusively with science podcasts, in particular on Recreational Science. In this communication we discuss the above mentioned trends and show our experience in the last two years in participating at Science Fairs and university-sponsored events to attract students to science and technology careers. We show a combination of real examples (e.g., mathemagic), imagination, use of information technology, and use of social networks. We present as well an experience on designing a computational, interactive tool to promote chemistry among high school, prospective students using computers ("Dancing with Bionanomolecules"). Like the concepts related to Web 2.0, it has been already proposed that a new framework for communication of science is emerging, i.e., Science Communication 2.0, where people and institutions develop new innovative ways to explain science topics to diverse publics – and where Recreational Science is likely to play a leading role

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L’objectiu d’aquest projecte és el desenvolupament d’una eina de generació de xarxes de carrers a partir d’exemples. L’eina ha de permetre generar una xarxa de carrers nova que sigui semblant a l’existent en un mapa vectorial donat. A més, també es pretén unir aquesta aplicació amb l’urbanEngine per tal de poder generar vistes en 3D sobre aquestes xarxes de carrers, a més d’ampliar les opcions de l’urbanEngine a l’hora de crear ciutats

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Según Philip Kotler, considerado el padre del mercadeo, (en su libro Principles Of Marketing) la mercadotecnia es «el proceso social y administrativo por el cual los grupos e individuos satisfacen sus necesidades al crear e intercambiar bienes y servicios». La presente investigación tomará como punto de referencia para conceptualizar el marco teórico, la historia y evolución del mercadeo y sus actuales tendencias y rumbos; así como la incidencia que tiene en la planificación del área de mercadeo para las empresas que siguen este tipo de corrientes contemporáneas. Durante el desarrollo de la presente investigación se analizaran las nuevas tendencias de mercadeo basándose en la evolución y su referencia histórica. Ahora, se verá cómo el e-marketing compone una nueva estrategia para el desarrollo de ventaja competitiva entendiéndose ésta como un conjunto de atributos de una empresa que la distinguen de sus competidores. Este nuevo marketing que se quiere presentar, Total e-marketing, se compone del posicionamiento de la organización en la realidad virtual. Se utilizarán como factores claves de éxito en el posicionamiento de la organización en buscadores de internet como redes, wikipedia, google, facebook, etc.

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El Projecte s’ha desenvolupat dintre del Grup de Geometria i Gràfics de la Udg on es treballa amb projectes de desenvolupament urbanístic 3D. L’objectiu del projecte consisteix en construir una aplicació per simular l’evolució de ciutats expandint els carrers al llarg del temps. L’aplicació es desenvoluparà dintre del projecte urbanEngine incorporant la possibilitat d’expandir ciutats com una extensió d’aquest. A més es vol dissenyat una interfície gràfica d’usuari que faciliti les tasques de configuració i supervisió del sistema

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Propuesta de creación de un espacio reactivo potencial con la particularidad de la estructuración, preparación y desarrollo artístico. Se trata de una instalación con estructura regular en la que se ocultan las obras en ausencia de público con la intención de preservar la exhibición. Estructura virtual que oculta la obra de arte expuestas en ausencia de observador. Mecanismos prácticos de creación de entornos tridimensionales y escenarios. Programación en lenguaje visual basic para accionadores automáticos aleatorios. Sistemas de navegación virtual Quicktime vr.vrml y diseño del espacio de representación artístico interactivo. Objetos, situación y configuraciones. Iluminación. Renderizados. Software informático 3D y tecnología VRML (Virtual Reality Modeling Languaje). Proceso investigador directamente ligado a la creación artística y las nuevas tecnologías. metodología cualitativa experimental de representación educativa sobre los sujetos que contemplan los programas. La percepción del arte es variable en el espacio y el tiempo siendo ello una condición que no fija la obra en una ubicación única y perdurable sino que varía en relación con la disposición consciente e inconsciente del sujeto en su entorno. Tratándose de un sistema de representación artístico inédito podrá servir de puerta a nuevas líneas de investigación en el arte activo, multiusuario, reactivo e integral.

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One of the key aspects in 3D-image registration is the computation of the joint intensity histogram. We propose a new approach to compute this histogram using uniformly distributed random lines to sample stochastically the overlapping volume between two 3D-images. The intensity values are captured from the lines at evenly spaced positions, taking an initial random offset different for each line. This method provides us with an accurate, robust and fast mutual information-based registration. The interpolation effects are drastically reduced, due to the stochastic nature of the line generation, and the alignment process is also accelerated. The results obtained show a better performance of the introduced method than the classic computation of the joint histogram

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RESUMO:O hábito de ler é decorrente do exercício e nem sempre se constitui num ato prazeroso, porém, sempre necessário. Por este motivo se deve recorrer a estímulos para criar o hábito de leitura em nossos alunos. Desta forma, a disciplina de Educação Física pode também contribuir para este processo. Por ser uma disciplina que envolve a dimensão motora, cognitiva e expressionista, a sua relação com a leitura é quase que intrínseca, porém, viabilizada de formas diferentes. É certo que a criança não conseguirá na sua totalidade, uma absorção intelectual explícita da leitura para construir uma realidade virtual e representar em gestos corporais, a partir de um conjunto léxico de significantes e significados correspondentes à postura física. No entanto, o exercício da leitura desenvolve na criança capacidades cognitivas de mais valia que lhe possibilita níveis satisfatórios de representatividade corporal. As atividades recreativas oferecem, sem dúvida, um processo excepcional para fazer as crianças tomarem parte ativamente no processo do ensino, como participantes, em vez de meros espectadores. A proposta deste trabalho de intervenção busca auxiliar o professor de Educação Física no campo de atuação profissional do pesquisador, tendo como delimitação do campo de investigação o Centro de Educação Básica Governador Freitas Neto, escola da rede municipal de Educação de Teresina e, Colégio Lerote, da rede particular de Teresina. Deste modo, os objetivos do presente estudo consistem em analisar as contribuições da disciplina de Educação Física para a aprendizagem do ensino da prática de leitura com crianças do Ensino Fundamental, nas séries iniciais com escolas da rede municipal e particular da cidade de Teresina – Piauí. Concluiu-se que com um trabalho integrado da Educação Física com o processo de alfabetização nas primeiras séries do Ensino Fundamental, essa etapa pode ser vista de forma rica e ampla. Assim, com essa contribuição, aprender a ler e escrever pode, pois, se tornar mais natural e mais divertido. ABSTRACT: The habit of reading is a result of exercise and is not always a pleasurable act, but always necessary. For this reason one should resort to incentives to create the reading habit in our students. Thus, the discipline of Physical Education can also contribute to this process. Because it is a discipline that involves the size motor, cognitive and expressionistic, their relationship with reading that is almost inherent, however, made possible in different ways. It is true that the child can not in its entirety, an explicit intellectual absorption of reading to construct a virtual reality and represented body gestures from a whole lexicon of signifiers and meanings corresponding to the physical posture. However, the exercise of reading the child develops cognitive abilities that enables him to gain more satisfactory levels of representative body. The recreational activities offer, no doubt, an exceptional procedure to make the children take part actively in the process of education, as participants rather than spectators. The purpose of this intervention work intends to help the physical education teacher in the professional field of research, with the delimitation of the field of research the Centre for Basic Education Governador Freitas Neto, the municipal school of Teresina and Education, College Lerote, from private Teresina. Thus, the objectives of this study are to analyze the contributions of physical education for learning the practice of teaching reading with children of elementary school, in the early grades with municipal schools and particularly the city of Teresina - Piauí. It was concluded that with an integrated physical education with the acquisition of literacy in the early grades of elementary school, this step can be seen in a rich and broad. So, with this contribution, learning to read and write may therefore become more natural and fun.

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Esta dissertação surgiu com o intuito de criar uma prova neuropsicológica com todas as características das tradicionais provas de papel e lápis, com o acréscimo de vantagens que as novas tecnologias lhe podem trazer. Desta forma, desenvolveu-se um ambiente virtual com um propósito avaliativo, semelhante ao da prova em papel Trail Making Test e posteriormente ao seu desenvolvimento elaborou-se uma aplicação que foi testada em dois grupos. Compostas por um total de 47 elementos, estas amostras abrangeram população com e sem diagnóstico de problemas de alcoolismo (Síndrome de Dependência Alcoólica), que foram submetidas à execução das provas Cozinha Virtual e Trail Making Test. Os dados daí resultantes comprovam a capacidade desta prova avaliar os défices cognitivos ao nível da flexibilidade cognitiva, da capacidade de sequenciação, de procura visual, velocidade motora e capacidades atencionais e confirmam também a sua correlação com a prova que lhe deu origem.

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Este texto toma por objeto el conjunto de la obra de Eugenio Espejo (Quito, 1747-1795) para recorrer en ella su complejo sistema de desdoblamientos, proyecciones y ocultamientos –fundamentados en el mecanismo del anónimo– que la ubican como el caso más interesante y significativo de las letras ecuatorianas en lo que se refiere a la génesis autoral. El propósito de Landázuri es sintetizar y ordenar la información existente sobre los procedimientos de desdoblamiento o anonimato visibles en la obra de Espejo y tratar de comprenderlos a la luz de los mecanismos discursivos del barroco, enfrentados –o asimilados– en el paradigma dieciochesco de la Ilustración. Para ello, acude a las tesis de Bolívar Echeverría sobre el “ethos barroco” y sus relaciones con la concepción de modernidad, lo cual sin duda permite una comprensión bastante amplia de lo que ocurre en la obra y cosmovisión de Espejo como síntesis y caso significativo de su época.

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Climate models suggest that extreme precipitation events will become more common in an anthropogenically warmed climate. However, observational limitations have hindered a direct evaluation of model-projected changes in extreme precipitation. We used satellite observations and model simulations to examine the response of tropical precipitation events to naturally driven changes in surface temperature and atmospheric moisture content. These observations reveal a distinct link between rainfall extremes and temperature, with heavy rain events increasing during warm periods and decreasing during cold periods. Furthermore, the observed amplification of rainfall extremes is found to be larger than that predicted by models, implying that projections of future changes in rainfall extremes in response to anthropogenic global warming may be underestimated.