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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
381

Design and evaluation of a visual rapid prototyping environment in an existing smart home platform

Hamada, Skander January 2017 (has links)
Recent advances in the field of Internet of Things (IoT) are placing its own vision, as a platform of interconnected services and devices, at the heart of the smart home concept. This consolidation promises a new wave of innovative products designed in the open, and in which the user takes center stage starting from the very first steps. Therefore, researchers as well as product designers in these increasingly related fields are now tasked with a more complex mission when investigating user behavior. In this thesis we consider rapid prototyping as the upcoming standard process for investigating user interactions in the future smart home. Although past research contributed with several self-contained solutions (built from scratch) to allow such investigations, no accounts were found tackling the problem from our perspective, in which the focus is on how to enable rapid prototyping in an existing proprietary smart home platform by using open standards, software and hardware. To answer this question, we conducted our research with participation of academic researchers and professional designers in the context of an academic and industrial partnership, in an ongoing smart home research project. We used an approach based on the design science research process in combination with the user centered design (UCD) and agile software development methodologies. During this thesis we performed an end to end design process starting from ideation to implementation and evaluation; an architectural blueprint was proposed and a working prototype of our visual smart home rapid prototyping environment (SHRPE) was implemented and tested. The obtained results demonstrate the feasibility of enabling visual rapid prototyping capabilities in an existing smart home platform, by using the system integration process to introduce available open standards, software and hardware tools into the platform. In addition, evaluation results of user testing confirmed that using UCD to iteratively capture user needs in such complex context is a solid approach.
382

3-D Computer-aided Design (CAD) and Computer Numerical Control (CNC) milling : An alternative to traditional ceramics master moulding technology

Du Plooy, Elsje. January 2014 (has links)
Thesis (M. Tech. (Design and Studio Art)) -- Central University of Technology, Free State, 2014 / This quantitative research project investigates the utilization of emerging technologies within the arts with a view on establishing an interdisciplinary approach between ceramics and engineering. The traditional manufacturing method of producing master moulds is a time-consuming process for the studio ceramicist. This study explores whether computer-aided design (CAD) and computer numerical control (CNC) milling can accelerate the design and manufacturing process when developing master moulds as an alternative to using traditional methods. It investigates whether SolidWorks® can be applied as a suitable CAD design tool for the creation of ceramic vessel forms in order to reduce the design development time frame. It furthermore investigates whether CNC milling can be used as a viable manufacturing technology for the making of vessel prototypes and master moulds from CAD data, the overall objective being to improve and accelerate the plaster of Paris master mould manufacturing process for the batch production of studio-based ceramic artefacts. Findings from this study indicate that emerging technologies have a lot to offer the artist when it comes to providing new possibilities for the creation of artefacts and that SolidWorks® and CNC milling can be utilized as a viable interdisciplinary manufacturing approach between ceramics and digital manufacturing technologies.
383

Neue Werkstoffe über additive Fertigung

Günther, Johannes, Niendorf, Thomas 04 October 2016 (has links) (PDF)
Über die additive Fertigung, oftmals bezeichnet als 3D-Druck, lassen sich Bauteile nahezu beliebiger geometrischer Komplexität herstellen. Gleichzeitig lassen die Prozessrandbedingungen die direkte Einstellung der Mikrostruktur in den verwendeten metallischen Werkstoffen zu. Hieraus ergeben sich weitreichende Möglichkeiten bezüglich der Eigenschaftsoptimierung aktueller Hochleistungswerkstoffe.
384

Gestion haut niveau et suivi en ligne de l'état de santé des batteries lithium-ion / High level management and online tracking of the state of health of lithium-ion batteries

Zenati, Ali 23 April 2012 (has links)
Les batteries lithium-ion sont considérées de nos jours comme la solution optimale pour les systèmes de stockage d'énergie, et cela est dû principalement à leurs hautes densités d'énergie et de puissance. Leurs performances, durées de vie, et fiabilités sont liées et dépendent des conditions d'utilisations telles que la température et les courants demandés par l'application. Et afin d'avoir un suivi de l'évolution du vieillissement de la batterie, la détermination de son état de santé (State-Of-Health -SOH-) est une fonction majeure à considérer. Ce mémoire expose les méthodologies ou techniques développées pour la gestion de la durée de vie de la batterie lithium-ion, et plus particulièrement pour la détermination de son état de santé, en se basant sur ses propres paramètres principaux qui sont la capacité et la résistance ohmique. Cette démarche permet de basculer d'un SOH statique (basé sur un modèle prédéfini de vieillissement tenant compte du calendaire et du cyclage en fonction des caractéristiques telles que la température et le courant de la batterie suivies en temps réel) vers un SOH dynamique ou auto-adaptatif, puisqu'il est basé sur un modèle du composant électrochimique dont les paramètres précédents sont évaluées en temps réel en fonction des conditions d?utilisation. Le premier chapitre revient sur les généralités concernant la technologie lithium-ion : caractéristiques, performances, constitution de l'élément de stockage, choix et nature des électrodes... Le principe de fonctionnement avec les équations générales des phénomènes électrochimiques sont aussi développés. Le second chapitre est un état de l'art des méthodologies de prédiction de la durée de vie avec les différentes classifications des modèles et des techniques de prédiction. Puis lors du troisième chapitre, nous aborderons nos méthodologies développées et les techniques utilisées, telles que le calcul statistique, la logique floue et les lois de vieillissement pour la détermination d'un état de santé dynamique de la batterie, qui en plus de la prise en compte de l'état de santé statique, c'est-à-dire basé seulement sur le vieillissement calendaire et en cyclage, considérera aussi l'évolution de la capacité et de la résistance ohmique de la batterie, en fonction du temps et des conditions d'utilisation, permettant ainsi de considérer les phénomènes improbables. Enfin dans le dernier chapitre, nous exposerons les résultats obtenus lors des tests de validations sur banc de puissance et de prototypage rapide sur des éléments réels / Lithium-ion batteries are considered nowadays as the optimal issue for the energy storage systems, it is mainly due to their high energy and power density. Their performances, lifetime, and reliability are related and depend on the operating conditions such as the temperature and requested current by the application. And in order to track the evolution of the ageing of the battery, the determination of its State-Of-Health -SOH- is a major function to consider. This thesis presents both methodologies and techniques developed for the management of the lifetime of lithium-ion battery, and more particularly the assessment of its state-of-health, based on its own main parameters which are the capacity and the ohmic resistance. This approach allows to switch from a static SOH (based on a predefined ageing model, which take into account the calendar and cycling ageing of the battery, according to some characteristics such as the temperature and the courant of the battery tracked in real time) to a dynamic SOH (self-adaptive) using an online assessment of the previous parameters according to the operating conditions. The first chapter is an overview about the lithium-ion technology: characteristics, performances, cell design, choice and nature of the electrodes... The operating principle with the general equations are also developed. The second chapter is a state of the art of the lifetime prediction methodologies with the different kinds of classification of models and prediction techniques. Then in the third chapter, we will discuss our methodologies and the developed techniques, such as the use of statistics, fuzzy logic and rules of ageing to assess a dynamic state of health of the battery, which not only does take into account the static SOH (calendar and cycling ageing), but also considers the evolution of the ohmic resistance and the capacity of the battery, depending on the time and the operating conditions. This allows taking into consideration unlikely phenomena. Finally, in the last chapter, we will expose obtained results from validation tests. These tests were done under a power electrical testbench and a rapid prototyping testbench with real cells
385

Participació ciutadana i inclusió social en les comunitats de persones cegues: un estudi d'educació artística basat en el mestratge de la professora Rosa Gratacós

Cebrià Pairoli, Anna 24 May 2013 (has links)
The construction of this thesis is developed from different conceptual interlacing axis that created a networking weave through which the field of investigation was debated and defined and a project of collaborative citizenship with the goal of providing an improvement in the social environment from which the visual impairment through art was built. Firstly, we speak about the context in which, in a dialogic way, the identity of Ph. D. Rosa Gratacós Masanella has grown and developed. With the help of the narrative research and the life story methods we make an approach to the life time experience of the main character of our investigation, in order to understand her social, political and educational context, how it relates to her personal life, her work as a professor and her artistic career, and how all these different perspectives have points in common. We also approach those people who met our protagonist, those who were her referents or were important in the evolution of her identity. We point Ph. D. Rosa Gratacós pioneer investigation in the field of visual impairment and we finally explain the multisensory project of The Senses Labyrinth, a project that was born from the idea of universal accessibility from the perspective of blind people. Sensory education, game and art become the source of teaching and learning for the researcher and they are applied together to art education and artistic perception from blindness, through service and learning methodologies / La construcció d’aquesta tesi es desenvolupa a partir de diferents eixos conceptuals que es van anar entrellaçant, configurant un entramat de networking a través del qual es va posar en conflicte, es va definir el mapa del territori de la investigació, i es va generar un projecte col•laboratiu de participació ciutadana amb l’objectiu d’aportar una millora qualitativa a l’entorn ciutadà a través de l’art i a partir de la discapacitat visual. En primer lloc, parlem del context en el que, de manera dialògica, creix i es desenvolupa la identitat de la Dra. Rosa Gratacós Masanella, a partir dels mètodes d’investigació narrativa i del relat de vida per reconstruir una aproximació a la seva historia de vida que permeti entendre el context social, polític i educatiu d’aquest trajecte vital en relació a la investigadora, a la seva pròpia experiència i al seu relat de vida, factors que coincideixen en alguns punts, com són la vessant artística, educativa i investigadora, amb més o menys distància i des d’on creix l’interès per l’estudi. També ens aproximem als subjectes que han tingut relació amb la protagonista com a referents i portes d’entrada al canvi i al desenvolupament de la pròpia identitat. Situem la investigació pionera de la Dra. Rosa Gratacós relacionada amb la discapacitat visual i finalment els eixos que han teixit tot el relat es cohesionen i es presenta el projecte multisensorial de La forma de les olors, que parteix de la idea d’accessibilitat universal, iniciada des de la discapacitat visual. L’educació sensorial, el joc i l’art esdevenen la font de l’ensenyament-aprenentatge de la investigadora i s’apliquen conjuntament a l’educació artística i a la investigació de la percepció artística des de la ceguesa, a través de metodologies d’aprenentatge i servei
386

In Vitro Fluid Dynamics of Stereolithographic Single Ventricle Congenital Heart Defects From In Vivo Magnetic Resonance Imaging

Kitajima, Hiroumi D. 20 July 2007 (has links)
Background: Single ventricle congenital heart defects with cyanotic mixing between systemic and pulmonary circulations afflict 2 per 1000 live births. Following the atriopulmonary connection proposed by Fontan and Baudet in 1971, the present procedure is the total cavopulmonary connection (TCPC), where the superior vena cava (SVC) and inferior vena cava (IVC) are sutured to the left pulmonary artery (LPA) and right pulmonary artery (RPA). However, surgeon preference dictates the implementation of the extra-cardiac and intra-atrial varieties of the TCPC. Overall efficiency and hemodynamic advantage of the competing methodologies have not been determined. Hypothesis: It is hypothesized that an understanding of the experimental fluid dynamic differences between various Fontan surgical methodologies in the TCPC allows for power loss evaluation toward improved surgical planning and design. Methods: Toward such analysis, a previously developed data processing methodology is applied to create an anatomic database of single ventricle patients from in vivo magnetic resonance imaging (MRI) to examine the gamut of TCPC anatomies. From stereolithographic models of representative cases, pressure and flow data are used to quantify control volume power loss to measure overall efficiency. particle image velocimetry (PIV) is employed to detail flow structures in the vasculature. Results are validated with dye injection flow visualization and 3-D phase contrast magnetic resonance imaging (PC-MRI) velocimetry, highlighting flow phenomena that cannot be captured with in vivo MRI due to prohibitively long scanning times. Preliminary results illustrate the variation of control volume power loss over several TCPC anatomies with varying flow conditions, the application of PIV, and validation approaches with 3-D PC-MRI velocimetry. Data from control volume power loss evaluation demonstrate a correlation with TCPC anatomy, providing added clinical knowledge of optimal TCPC design. Findings from PIV and 3-D PC-MRI velocimetry reveal a means for quantitatively comparing flow structure. Dye injection flow visualization offers qualitative insight into limitations of the selected velocimetry techniques.
387

Transformations de graphes pour la modélisation géométrique à base topologique / Graph transformations for topology-based geometric modelling

Bellet, Thomas 10 July 2012 (has links)
De nombreux domaines comme le jeu vidéo, l’architecture, l’ingénierie ou l’archéologie font désormais appel à la modélisation géométrique. Les objets à représenter sont de natures diverses, et leurs opérations de manipulation sont spécifiques. Ainsi, les modeleurs sont nombreux car tous spécialisés à leur domaine d’application. Or ils sont à la fois chers à développer, souvent peu robustes, et difficilement extensibles. Nous avons proposé dans la thèse l’approche alternative suivante :– fournir un langage dédié à la modélisation qui permet de définir les opérations quelque soit le domaine d’application ; dans ce langage, les objets sont représentés avec le modèle topologique des cartes généralisées, dont nous avons étendu la définition aux plongements ; les opérations sont elles définies par des règles de transformation de graphes, issues de la théorie des catégorie ;– garantir les opérations définies dans le langage à l’aide de conditions de cohérence ; une opération dont la définition vérifie ces conditions ne produit pas d’anomalie ;– développer un noyau de modeleur générique qui interprète ce langage ; les opérations définies sont directement appliquées dans le modeleur, sans implantation dans un langage de programmation ; l’outil assure également la vérification automatique des conditions du langage pour prévenir un utilisateur lorsqu’il propose une opération incohérente.Le langage et le modeleur développés se sont révélés performants à la fois en termes de temps de développement et en termes de temps machine. L’implantation d’une nouvelle opération par une règle ne prend que quelques minutes à l’aide des conditions du langage, au contraire de l’approche classi / Geometric modeling is now involved in many fields such as: video games, architecture, engineering and archaeology. The represented objects are very different from one field to another, and so are their modeling operations. Furthermore, many specific types of modeling software are designed for high programing costs, but with a relatively low rate of effectiveness.The following is an alternative approach:– we have conceived a dedicated language for geometric modeling that will allow us to define any operation of any field; objects in this language are defined with the topological model of generalized maps, this definition has been extended to the embedding informations; here the operations are defined as graph transformation rules which originate from the category theory;– we have ensured operation definitions with consistency conditions; these operations that satisfy those conditions do not generate anomalies; – we have designed generic modeling software to serve as an interpreter of this language; the operation definitions are directly applied without the need for more programing; the software also automatically checks the language conditions and warns the user if he designs a non-consistent operation.The provided language and software prove to be efficient, and all for a low programing cost. Designing a new operation takes only minutes thanks to the language conditions, as opposed to hours of programming and debugging with the past approach.
388

Estudo de tecnicas de otimização da programação de codigos de DSP em FPGA / Study of optimization techniques for DSPs codes programming in FPGA

Lemes Filho, Jose Matias 14 August 2018 (has links)
Orientador: Luis Geraldo Pedroso Meloni / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-14T05:58:36Z (GMT). No. of bitstreams: 1 LemesFilho_JoseMatias.pdf: 2987431 bytes, checksum: 93fc757a06215b93a08427d2f33f88a2 (MD5) Previous issue date: 2009 / Resumo: Este trabalho descreve o estudo, a pesquisa e compilação de técnicas de otimização de códigos em FPGA (Field Programmable Gate Arrays) utilizando uma ferramenta de prototipagem rápida. Para isso, foram implementados alguns algoritmos para auxiliar na apresentação e avaliação de quatro técnicas de otimização: uso de recursos alternativos, multiplexação no tempo, algoritmos alternativos e mudança da freqüência sistêmica. As principais contribuições do presente trabalho foram: compilar em um único documento diversas técnicas para geração eficiente de códigos de processamento digital de sinais; o estudo das etapas de fluxo de projeto baseado em ferramentas de prototipagem rápida; implementações de diversos algoritmos para demonstrar as técnicas de otimização, visando-se o estudo da minimização da área de ocupação em FPGA. Com o uso das técnicas pode-se alcançar uma redução de área da FPGA de até 90%, conforme a complexidade do sistema alvo. / Abstract: This work describes the study, research and compilation of programming optimization techniques for FPGA (Field Programmable Gate Arrays) using a tool technology for rapid prototyping. For this purpose, some algorithms have been implemented to help the presentation and evaluation of four optimization techniques: alternative resources usage, time multiplexing, alternative algorithms and systemic frequency change. The main contributions of this work are: compilation in one document several efficient techniques for generation code in digital signal processing; study of the phases of design flow were based on rapid prototyping tools; implementations of several algorithms to demonstrate the optimization techniques, looking for the minimization of the FPGA occupation area. With the use of these techniques, it is possible to reach a FPGA area reduction of up to 90%, depending of the complexity of the target system. / Universidade Estadual de Campi / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
389

Analise de parametros fisicos e operacionais no fenomeno da cura localizada do processo termolitografico da prototipagem rapida / Operational and physical analysis for localized curing phenomenon of rapid prototyping thermolithography process

Rezende, Rodrigo Alvarenga 04 July 2006 (has links)
Orientador: Rubens Maciel Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-09T08:31:02Z (GMT). No. of bitstreams: 1 Rezende_RodrigoAlvarenga_M.pdf: 6027055 bytes, checksum: dc80f298be40be05219c739478682c4d (MD5) Previous issue date: 2006 / Resumo: A Prototipagem Rápida consiste na reprodução física de objetos tridimensionais de geometria livre, a partir de um projeto inicial (design), modelado por auxílio de computador. A Prototipagem Rápida é uma tecnologia moderna que une métodos e equipamentos adequados a fim de oferecer, como principais atrativos, alta qualidade e redução de custos de produtos manufaturados. São diversos os métodos existentes e os materiais aplicáveis. Este trabalho apresenta um novo método de fabricação de protótipos, a Termolitografia. Baseada na irradiação de laser de CO2 na região espectral do infravermelho sobre resinas termossensíveis, a Termolitografia oferece importantes vantagens quando comparada a outros processos, principalmente no que se refere ao estado físico da amostra logo após a irradiação do laser. Este processo apresenta duas grandes vantagens que são a não-contração da amostra após ser curada e a ausência de tratamento pós-cura. A cura localizada é o fenômeno de confinamento da energia transmitida pelo laser realizando a cura do material somente em uma região desejada. O controle da cura localizada é a chave para o sucesso e para a garantia de protótipos de alta qualidade. Para ajustá-la e otimizá-la, é necessário o domínio de parâmetros físicos do material empregado e de parâmetros operacionais do laser de CO2. O estudo da combinação dos efeitos, por exemplo, da variação da proporção dos componentes da amostra, da sua temperatura de cura, além de fatores operacionais como a velocidade de varredura, o diâmetro e a potência do feixe laser, é o alvo principal deste trabalho. As simulações facilitam a compreensão de como cada variável pode interferir na construção do protótipo, e determinam faixas de valores para os parâmetros as quais implicam em melhores resultados no final do processo. O trabalho de seleção destes valores é importante para a futura continuidade de estudo experimental do processo termolitográfico / Abstract: Rapid Prototyping consists on a physical replication of three-dimensional objects with free geometry, from an initial design, modeled by computer assistance. Rapid Prototyping is a modern technology that unifies methods and suited equipments in order to offer as main attractive high quality and cost-reduction of manufactured products. There are many techniques and raw materials applicable. This work presents a new method of prototypes fabrication, the Termolithography. Based on CO2 laser irradiation at the infrared spectral region onto thermosensitive resins, Thermolithography offers important advantages if compared with other processes, mainly those ones respected to the non-contraction effect of the sample after being cured and the absence of a post cure treatment. The localized cure is the phenomenon of confinement of energy transmitted by laser beam performing the curing only on a desired region at the sample. The control of the localized cure is the key for the success and for the guarantee of high quality prototypes. In order to fit and optimize it, it is necessary the domain of physical properties of the applied material and the domain of the CO2 laser operational parameters. The study of combination of the involved effects, for instance, the variation of amount of the components in the sample, the cure temperature, beside operational parameters as scanning velocity, the laser beam diameter and power, are the main target of this work. Simulations become easier the comprehension of how each variable can affect during the building of prototype and to determine the best range of values which implicate in better final result of the process. The selection of these values is very important to the continuity of this work / Mestrado / Desenvolvimento de Processos Químicos / Mestre em Engenharia Química
390

3D Printing for Computer Graphics Industry

Granath, Victor January 2011 (has links)
Rapid prototyping is a relativity new technology and is based on layered manufacturing which has similarities to the method an ordinary desktop paper printer works. This research is to obtain a better understanding on how to use computer graphics software, in this particular case Autodesk Maya, to create a model. The goal is to understand how to create a suitable mesh of a 3D model for use with a 3D printer and produce a printed model that is equivalent to the CAD software 3D model. This specific topic has not been scientifically documented which has resulted in an actual 3D model.

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