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2D and 3D high-speed multispectral optical imaging systems for in-vivo biomedical researchBouchard, Matthew Bryan January 2014 (has links)
Functional optical imaging encompasses the use of optical imaging techniques to study living biological systems in their native environments. Optical imaging techniques are well-suited for functional imaging because they are minimally-invasive, use non ionizing radiation, and derive contrast from a wide range of biological molecules. Modern transgenic labeling techniques, active and inactive exogenous agents, and intrinsic sources of contrast provide specific and dynamic markers of in-vivo processes at subcellular resolution. A central challenge in building functional optical imaging systems is to acquire data at high enough spatial and temporal resolutions to be able to resolve the in-vivo process(es) under study. This challenge is particularly highlighted within neuroscience where considerable effort in the field has focused on studying the structural and functional relationships within complete neurovascular units in the living brain. Many existing functional optical techniques are limited in meeting this challenge by their imaging geometries, light source(s), and/or hardware implementations. In this thesis we describe the design, construction, and application of novel 2D and 3D optical imaging systems to address this central challenge with a specific focus on functional neuroimaging applications. The 2D system is an ultra-fast, multispectral, wide-field imaging system capable of imaging 7.5 times faster than existing technologies. Its camera-first design allows for the fastest possible image acquisition rates because it is not limited by synchronization challenges that have hindered previous multispectral systems. We present the development of this system from a bench top instrument to a portable, low-cost, modular, open source, laptop based instrument. The constructed systems can acquire multispectral images at >75 frames per second with image resolutions up to 512 x 512 pixels. This increased speed means that spectral analysis more accurately reflects the instantaneous state of tissues and allows for significantly improved tracking of moving objects. We describe 3 quantitative applications of these systems to in-vivo research and clinical studies of cortical imaging and calcium signaling in stem cells. The design and source code of the portable system was released to the greater scientific community to help make high-speed, multispectral imaging more accessible to a larger number of dynamic imaging applications, and to foster further development of the software package. The second system we developed is an entirely new, high-speed, 3D fluorescence microscopy platform called Laser-Scanning Intersecting Plane Tomography (L-SIPT). L-SIPT uses a novel combination of light-sheet illumination and off-axis detection to provide en-face 3D imaging of samples. L-SIPT allows samples to move freely in their native environments, enabling a range of experiments not possible with previous 3D optical imaging techniques. The constructed system is capable of acquiring 3D images at rates >20 volumes per second (VPS) with volume resolutions of 1400 x 50 x 150 pixels, over a 200 fold increase over conventional laser scanning microscopes. Spatial resolution is set by choice of telescope design. We developed custom opto-mechanical components, computer raytracing models to guide system design and to characterize the technique's fundamental resolution limits, and phantoms and biological samples to refine the system's performance capabilities. We describe initial applications development of the system to image freely moving, transgenic Drosophila Melanogaster larvae, 3D calcium signaling and hemodynamics in transgenic and exogenously labeled rodent cortex in-vivo, and 3D calcium signaling in acute transgenic rodent cortical brain slices in-vitro.
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Experimental Study of Rocking Motion of Rigid Bodies on Deformable Medium via Monocular VideogrammetryGreenbaum, Raphael January 2014 (has links)
The study of rigid body rocking is applicable to a wide variety of structural and non-structural elements. The current applications range from bridge pier and shallow footing design to hospital and industrial equipment, even art preservation. Despite the increasing number of theoretical and simulation studies of rocking motion, few experimental studies exist. Of those that have been published, most are focused on a constrained version of the complete problem introducing modifications to the physical problem with the purpose of eliminating either sliding, uplift or the three dimensional response of the body. However, all of these phenomena may affect the response of an unrestrained rocking body. Furthermore, the majority of the experimental studies that have been published have used methods that are ill-suited to comprehensive three dimensional experimental analysis of the problem.
The intent of this work is two-fold. First, to present a computer vision method that allows for the experimental measurement of the rigid body translation and rotation time histories in three dimensions. Experimental results obtained with this method will be presented to demonstrate that it obtains greater than 97% accuracy when compared against National Institute of Standards and Technology traceable displacement sensors. The experimental results highlight important phenomena predicted in some state-of-the-art models for 3D rocking behavior. Second, to present experimental evidence of the importance of characterizing the support medium as deformable instead of the commonly assumed rigid model. It will be shown in this work that this assumption of a rigid support may in some cases lead to non-conservative analysis that is unable to predict rocking motion and, in some cases, even failure.
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Maquetes: o estado da arte / Models: the state of the artRotelli, Vanderlei 24 May 2017 (has links)
Este estudo se propõe a falar sobre as maquetes de apresentação, que são executadas por profissionais especializados, para o Mercado Imobiliário. Foi feito um levantamento sobre como este mercado trabalha atualmente no Brasil, estudando metodologias, materiais e maquinários utilizados. Para tanto, foram feitas visitas técnicas a três das principais empresas especializadas no setor, documentando fotograficamente as formas de trabalho, os materiais mais utilizados e quais máquinas podem ser encontradas. Foi analisada, também, uma das inovações mais recentes e revolucionárias nesta área que é a Fabricação Digital (FD), que, além de influenciar diretamente o setor de construção de maquetes, está alterando a metodologia de trabalho dos arquitetos e designers, pois torna muito mais tênue a linha entre o desenho digital e a execução do modelo físico. Para tanto, foi feita uma visita técnica em um dos doze FabLabs Livres SP, abertos a todos os interessados na cidade de São Paulo, onde foi avaliado omaquinário disponível e suas possibilidades de uso, bem como o acesso aesta nova tecnologia disponibilizada pela Prefeitura Municipal de São Paulo. Estes Laboratórios são abertos ao público e oferecem, além do acesso direto às máquinas, cursos que ensinam a projetar e utilizar esta nova tecnologia. / This study intends to talk about the models of presentation, which are carried out by specialized professionals, for the Real Estate Market. A survey was made on how this market currently works in Brazil, studying methodologies, materials and machinery used. For that, technical visits were made to three of the main companies specialized in this sector, photographically documenting the forms of work, the most used materials and which machines were found there. It was also analyzed one of the most recent and revolutionary innovations in this area that is Digital Fabrication (FD), which, in addition to directly influencing the model construction sector, is changing the architects\' and designers\' working methodology since it makes thinner the line between the digital drawing and the completion of the physical model. A technical visit was made to one of the twelve FabLabs Livres SP, open to all interested in the city of São Paulo, where the available machinery and their possibilities of use were evaluated, as well as the access to this new technology provided by the City Hall Municipality of São Paulo. These laboratories are open to the public and offer courses on how to design and use this new technology. In addition, they offer direct access to the machines.
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Validação de medidas maxilofaciais por meio da tomografia computadorizada por feixe cônico em 3D / Assessment of linear and angular measurements on three-dimensional conebeam computed tomographic imagesMoreira, Carla Ruffeil 01 October 2009 (has links)
O objetivo deste estudo foi demonstrar a precisão e a acurácia de medidas maxilofaciais lineares e angulares obtidas por tomografia computadorizada por feixe cônico (TCFC). A amostra consistiu de quinze crânios humanos secos submetidos à TCFC. Medidas lineares e angulares foram realizadas em imagens em terceira dimensão (3D) após a identificação de pontos craniométricos convencionais. As imagens em 3D-TCFC foram analisadas por dois radiologistas, duas vezes, independentemente. Medidas físicas foram realizadas por um terceiro examinador utilizando paquímetro e goniômetro digitais. Os resultados não demonstraram diferenças estatísticas significantes para as análises intra e interexaminadores. As comparações entre as medidas físicas e as obtidas em 3D-TCFC para ambos os examinadores também não foram estatisticamente significantes tanto para as medidas lineares quanto paras as angulares (p= 0,968 e 0,915, p= 0,844 e 0,700, respectivamente). As imagens em 3D-TCFC podem ser utilizadas com precisão e acurácia para a obtenção de medidas lineares e angulares a partir de estruturas anatômicas e pontos craniométricos. / The purpose of this research was to provide further evidence to demonstrate the precision and accuracy of maxillofacial linear and angular measurements obtained by cone-beam computed tomography (CBCT) images. The study population consisted of 15 dry human skulls that were submitted to a CBCT, and threedimensional (3D) images were generated. Linear and angular measurements based upon conventional craniometric anatomical landmarks, were identified in 3D-CBCT images by two radiologists twice each independently. Subsequently physical measurements were made by a third examiner using a digital caliper and a digital goniometer. The results demonstrated no statistically significant difference between inter and intra-examiner analysis. Regarding accuracy test, no statistically significant difference were found of the comparison between the physical and CBCT-based linear and angular for both examiners (p= 0.968 and 0.915, p= 0.844 and 0.700 respectively). 3D-CBCT images can be used to obtain dimensionally accurate linear and angular measurements from bony maxillofacial structures and landmarks.
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Reconstrução tri-dimensional de imagens obstétricas de ultra-som utilizando linguagem computacional Java e OpenGL / Reconstruction three-dimensional of obstetritics images of ultrasound using computational language JAVA and OpenGLGoes, Claudio Eduardo 15 June 2007 (has links)
Este projeto de pesquisa trata da elaboração de um sistema de reconstrução de imagens obstétricas de fetos, em aparelhos de ultra-som convencionais, para a visualização dessas imagens em três dimensões utilizando a internet como meio de utilização do sistema, com o principal objetivo de proporcionar aos médicos ginecologistas melhor visualização do formato e das estruturas internas, e em especial da face do feto, através do processo de reconstrução tridimensional feito a partir de um conjunto de imagens bidimensionais capturadas em aparelhos convencionais de ultra-som. O uso clínico deste projeto está previsto para o setor de obstetrícia do Hospital das Clínicas de Ribeirão Preto. / This project of research deals with the laboration of a reconstruction system of obstetrics images of embryos in devices of ultrasound will be conventional the visualization of these images in three dimensions using the internet half of uses of the system, with the main objective provides to the medical gynecologists a better visualization of the format and the internal structures and in special the face of the embryo through the made process of three-dimensional reconstruction from a dataset of captured bi-dimensional images in conventional devices of ultrasound. The clinical uses of this project is foreseen will be the sector of obstetrics of the Hospital of the Clinics of Ribeirão Preto.
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Análises tensão-deformação de estruturas de solo grampeado. / Stress-Strain analysis of soil nailed structures.Najar Jiménez, Alexei Gino 17 April 2008 (has links)
Os métodos de equilíbrio limite comumente utilizados no dimensionamento de estruturas de solo grampeado não oferecem informação sobre as tensões e deformações na estrutura. No entanto, o êxito da técnica pressupõe deslocamentos para que a resistência dos grampos seja mobilizada. Portanto, seria desejável conhecer: os deslocamentos que a estrutura. sofre durante e depois de realizado o processo da escavação; os esforços mobilizados nos grampos; e a distribuição de tensões atrás da parede da escavação. A importância deste estudo é maior em situações em que a previsão do comportamento é a responsável por garantir a segurança de construções e de instalações de serviço público próximas às escavações grampeadas. Análises bidimensionais e tridimensionais de tensão-deformação com elementos finitos foram realizadas para um melhor entendimento do comportamento da estrutura. As comparações dos resultados das modelagens numéricas permitiram conhecer várias vantagens e desvantagens de um e de outro tipo de modelagem. Realizaram-se também comparações entre resultados de modelagens numéricas que utilizaram os seguintes modelos constitutivos: elasto-plástico (com critério de ruptura de Mohr-Coulomb), hiperbólico e elástico-linear, sendo que para este último realizou-se uma análise incremental. Para a aplicação do modelo elástico-linear foi necessária a divisão do maciço em regiões em função do tipo de trajetória de tensão. Essas comparações permitiram concluir que, desde que com a correta especificação dos parâmetros elásticos, a modelagem baseada na Teoria da Elasticidade pode representar bem o comportamento de escavações grampeadas. / The limit equilibrium methods that are frequently used for design of soi nailing structures do not provide information about the structure\'s stress and strain. However, the technique\'s success depends on the displacements that mobilize the nails strength. Therefore it is desirable to predict the structure\'s displacement, during and after the excavation; the forces avting on nails; and the stress distribution behind the excavation wall. This study has its importance increased in situations in which the prediction of the behavior is needed to guarantee the safety of adjacent buildings and municipal installations near to the excavation. Three dimensional and two-dimensional fine element stress-strain analyses were carried out for a better understanding of the behavior of the structure. Comparisons of the results of different numerical models led to a clear picture of advantages and disadvantages of different approaches. Numerical comparisons were also carried out between analyses with different constitutive models: elasto-plastic (Mohr-Coulomb), hyperbolic and incremental linear elastic. Application of the linear elastic model required the division of the soil mass in regions, according to stress path. Those comparisons led to the conclusion that, given correctly specified elastic parameters, Theory of Elasticity is able to correctly model the behavior of nailed excavations.
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Generic template based 3D object reconstruction using regional partitioning.January 2006 (has links)
Tong Kai Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (leaves 76-80). / Abstracts in English and Chinese. / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Previous and related works --- p.2 / Chapter 1.3 --- The Proposed Method --- p.4 / Chapter 1.4 --- Thesis outline --- p.6 / Chapter 2. --- Global deformation --- p.8 / Chapter 2.1 --- Feature points --- p.8 / Chapter 2.2 --- The deformation --- p.9 / Chapter 2.2.1 --- Deformation using affine transformation --- p.9 / Chapter 2.2.2 --- Elastic warping using Radial Basis Functions --- p.12 / Chapter 2.2.3 --- Biharmonic and triharmonic basic functions --- p.16 / Chapter 3. --- Local iterative surface fitting --- p.19 / Chapter 3.1 --- Basic closest point method --- p.19 / Chapter 3.2 --- Regional partitioning method --- p.27 / Chapter 3.2.1 --- Defining the regions --- p.29 / Chapter 3.2.2 --- Propagating from the seeds --- p.31 / Chapter 3.2.3 --- Handling the distortions --- p.36 / Chapter 3.3 --- Combined methods for surface fitting --- p.41 / Chapter 3.3.1 --- Summary of the surface fitting methods --- p.41 / Chapter 3.3.2 --- Combining the methods --- p.43 / Chapter 3.3.3 --- Fine-level fitting results --- p.47 / Chapter 4. --- Enhanced template based 3D Object reconstruction --- p.53 / Chapter 4.1 --- Compactly supported radial basis functions --- p.53 / Chapter 4.2 --- Reconstruction using two templates --- p.55 / Chapter 5. --- Implementations and Results --- p.60 / Chapter 5.1 --- Creation of 3D objects --- p.60 / Chapter 5.2 --- Feature points selection --- p.61 / Chapter 5.3 --- Experiment platform --- p.62 / Chapter 5.4 --- Results --- p.63 / Chapter 6. --- Conclusions --- p.71 / Chapter 6.1 --- Contributions --- p.72 / Chapter 6.2 --- Future developments --- p.72 / Appendix A --- p.73 / Voxel based closest point evaluation --- p.73 / References --- p.76
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Characterization of Ti-6Al-4V Produced Via Electron Beam Additive ManufacturingHayes, Brian J. 12 1900 (has links)
In recent years, additive manufacturing (AM) has become an increasingly promising method used for the production of structural metallic components. There are a number of reasons why AM methods are attractive, including the ability to produce complex geometries into a near-net shape and the rapid transition from design to production. Ti-6Al-4V is a titanium alloy frequently used in the aerospace industry which is receiving considerable attention as a good candidate for processing via electron beam additive manufacturing (EBAM). The Sciaky EBAM method combines a high-powered electron beam, weld-wire feedstock, and a large build chamber, enabling the production of large structural components. In order to gain wide acceptance of EBAM of Ti-6Al-4V as a viable manufacturing method, it is important to understand broadly the microstructural features that are present in large-scale depositions, including specifically: the morphology, distribution and texture of the phases present. To achieve such an understanding, stereological methods were used to populate a database quantifying key microstructural features in Ti-6Al-4V including volume fraction of phases, a lath width, colony scale factor, and volume fraction of basket weave type microstructure. Microstructural features unique to AM, such as elongated grains and banded structures, were also characterized. Hardness and tensile testing were conducted and the results were related to the microstructural morphology and sample orientation. Lastly, fractured surfaces and defects were investigated. The results of these activities provide insight into the process-structure-properties relationships found in EBAM processed Ti-6Al-4V.
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Modeling and rendering from multiple views. / CUHK electronic theses & dissertations collectionJanuary 2006 (has links)
The first approach, described in the first part of this thesis, studies 3D face modeling from multi-views. Today human face modeling and animation techniques are widely used to generate virtual characters and models. Such characters and models are used in movies, computer games, advertising, news broadcasting and other activities. We propose an efficient method to estimate the poses, the global shape and the local structures of a human head recorded in multiple face images or a video sequence by using a generic wireframe face model. Based on this newly proposed method, we have successfully developed a pose invariant face recognition system and a pose invariant face contour extraction method. / The objective of this thesis is to model and render complex scenes or objects from multiple images taken from different viewpoints. Two approaches to achieve this objective were investigated in this thesis. The first one is for known objects with prior geometrical models, which can be deformed to match the objects recorded in multiple input images. The second one is for general scenes or objects without prior geometrical models. / The proposed algorithms in this thesis were tested on many real and synthetic data. The experimental results illustrate their efficiency and limitations. / The second approach, described in the second part of this thesis, investigates 3D modeling and rendering for general complex scenes. The entertainment industry touches hundreds of millions of people every day, and synthetic pictures and 3D reconstruction of real scenes, often mixed with actual film footage, are now common place in computer games, sports broadcasting, TV advertising and feature films. A series of techniques has been developed to complete this task. First, a new view-ordering algorithm was proposed to organize and order an unorganized image database. Second, a novel and efficient multiview feature matching approach was developed to calibrate and track all views. Finally, both match propagation based and Bayesian based methods were developed to produce 3D scene models for rendering. / Yao Jian. / "September 2006." / Adviser: Wai-Kuen Chan. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1849. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 170-181). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
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Intégration et modélisation RF des interconnexions 3D pour l’interposeur photonique / Integration and RF modeling of 3D interconnects for photonic interposerMorot, Kevin 08 March 2018 (has links)
L'essor des réseaux de télécommunications à l'échelle mondiale génère un besoin croissant en termes de bande passante et de gestion de l'information. Le traitement de ces données requiert le développement de systèmes complexes, qui associent des fonctionnalités hétérogènes telles que des calculateurs numériques, des fonctions analogiques et des mémoires de stockage. L'approche originale retenue repose sur un degré d'innovation sans précédent dans le domaine de la microélectronique puisqu'elle mêle à la fois des technologies d'intégration 3D et le développement d'une filière photonique sur silicium. Des signaux très rapides (25, 40 ou 60 Gb/s) doivent donc être acheminés à travers les interconnexions 3D que sont le TSV (via traversant le silicium), les µ-bumps (connexions de cuivre entre les puces), les lignes de RDL (redistribution en face arrière) et les bumps qui assurent la communication vers l'extérieur. Il est nécessaire de développer de nouvelles technologies pour interconnecter les circuits à ces vitesses et de les modéliser finement jusqu'à de très hautes fréquences (>50 GHz), au moyen de techniques de caractérisation à développer, pour optimiser leur mode de réalisation. Ce travail de thèse se déroulera dans le cadre d'une collaboration tripartite et sera décomposé en quatre grandes étapes. 1. Spécifications des briques technologiques et de structures de test dédiées à l'évaluation de leurs performances dans le contexte de l'interposer photonique 2. Intégration des circuits de test, composés d'un empilement de puces logiques sur un interposer photonique, et adaptés au domaine fréquentiel visé avec les interconnexions 3D 3. Développement et mise en oeuvre des techniques de caractérisation à très haute fréquence des interconnexions 3D menant à l'extraction des modèles 4. Optimisation des lignes de transmission et des choix technologiques pour un routage efficace dans les architectures photoniques 3D / The worldwide growth of telecommunication networks drives an increasing need in terms of bandwidth and computing management. Data processing requires the development of complex system, which combines both heterogeneous functionalities such as numeric calculator, analog functions and memory storage. The original chosen approach is highly innovative in the field of microelectronics as it combines both 3D technologies and process integration for photonic on silicon. High speed signals (25, 40 or 60 Gb/s) are transmitted within the photonic interposer through 3D interconnects that are TSV (Trough-Silicon-Via), µ-bumps (copper connection in-between dies), RDL (Redistribution Line) and bumps (copper connection to the bottom access). Thereby, it is necessary to develop new technologies and new assemblies to interconnect and route efficiently those high speed circuits. Another challenge is to model them precisely for very high frequencies (>50 GHz), exploiting and developing the best characterization solutions in order to optimize the way to implement them. This PhD work will be performed in the frame of a tripartite collaboration and can be divided into four parts: 1. Specification of the key interconnects building-blocks and their associated test structures required to evaluate their performance in the context of a photonic interposer 2. Integration of the RF test circuits in the context of the stack of high speed logic dies over a photonic interposer using the developed 3D interconnects 3. Characterization of the test structures at very high frequency using dedicated characterization technics and extraction of equivalent models. Comparison with electromagnetic simulation 4. Validation of the technological and integration choices. Optimization of the transmission lines for efficient routing applied to 3D photonic structures
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