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1
Bufford, Laura. "3D-2D Dimension Reduction of Homogenized Thin Films." Research Showcase @ CMU, 2015. http://repository.cmu.edu/dissertations/520.
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Apel, Marcus. "A 3d geoscience information system framework." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-3300478.
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Two-dimensional geographical information systems are extensively used in the geosciences to create and analyse maps. However, these systems are unable to represent the Earth's subsurface in three spatial dimensions. The objective of this thesis is to overcome this deficiency, to provide a general framework for a 3d geoscience information system (GIS), and to contribute to the public discussion about the development of an infrastructure for geological observation data, geomodels, and geoservices. Following the objective, the requirements for a 3d GIS are analysed. According to the requirements, new geologically sensible query functionality for geometrical, topological and geological properties has been developed and the integration of 3d geological modeling and data management system components in a generic framework has been accomplished. The 3d geoscience information system framework presented here is characterized by the following features: - Storage of geological observation data and geomodels in a XML-database server. According to a new data model, geological observation data can be referenced by a set of geomodels. - Functionality for querying observation data and 3d geomodels based on their 3d geometrical, topological, material, and geological properties were developed and implemented as plug-in for a 3d geomodeling user application. - For database queries, the standard XML query language has been extended with 3d spatial operators. The spatial database query operations are computed using a XML application server which has been developed for this specific purpose. This technology allows sophisticated 3d spatial and geological database queries. Using the developed methods, queries can be answered like: "Select all sandstone horizons which are intersected by the set of faults F". This request contains a topological and a geological material parameter. The combination of queries with other GIS methods, like visual and statistical analysis, allows geoscience investigations in a novel 3d GIS environment. More generally, a 3d GIS enables geologists to read and understand a 3d digital geomodel analogously as they read a conventional 2d geological map.
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Mittelbach, Jens. "Die SLUB in 3D." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-79989.
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Öffentliche Gebäude, ob nun Kaufhäuser oder Bibliotheken, sind aufgrund ihrer Größe, ihrer oft originellen Architektur und der Vielfalt ihres Angebotes tendenziell unübersichtliche Räume, die mithilfe von Leitsystemen und Grundrissplänen erschlossen werden müssen. Anders als in Kaufhäusern, in denen die Juwelier-Abteilung schon aus der Ferne leicht vom Damenmoden- oder Sportartikel-Bereich zu unterscheiden ist, umfasst das Angebot von Bibliotheken traditionell in erster Linie physisch recht gleichartige Medien, die den Kunden in langen Regalreihen dargeboten werden. Das Problem der Unübersichtlichkeit ergibt sich hier also naturgemäß in schärferer Form. Gedruckte Übersichtspläne, in denen die Verteilung der Medienbestände entsprechend der jeweiligen Ordnungsprinzipien schematisch dargestellt werden, sind in Bibliotheken gang und gäbe. Schon seit geraumer Zeit bieten Bibliotheken natürlich Übersichtspläne auch online an, die eine mehr oder weniger ausgeprägte Funktionsvielfalt aufweisen und im günstigsten Falle direkt an den Bibliothekskatalog angebunden sind, so dass der Regalstandort eines dort gefundenen Buches mit einem Klick angezeigt werden kann. Gewöhnlich sind solche Übersichtspläne und Standortanzeigen zweidimensional und verharren, auch wenn sie im virtuellen Raum des Internets angeboten werden, in der Sphäre der physisch greifbaren Objekte. Das heißt, sie machen sicht- und auffindbar, was im realen Raum tatsächlich einen Platz einnimmt: gedruckte Bücher oder andere physische Medien, betretbare Gebäudeteile, Einrichtungsgegenstände oder Orte, an denen Dienstleistungen von Personen erbracht werden.
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Schaulin, Michael. "Optische 3D-Inspektion von Bauelementen der Systemintergration." Templin Detert, 2006. http://deposit.d-nb.de/cgi-bin/dokserv?id=3042214&prov=M&dok_var=1&dok_ext=htm.
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Lindt, Irma. "Adaptive 3D-User-Interfaces." München Verl. Dr. Hut, 2009. http://d-nb.info/993260241/04.
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Timmins, Nicholas E. "Extending the third dimension : novel methods and applications for 3D multicellular spheroids /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18289.pdf.
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Schaulin, Michael. "Optische 3D-Inspektion von Bauelementen der Systemintegration /." Templin : Detert, 2007. http://deposit.d-nb.de/cgi-bin/dokserv?id=3042214&prov=M&dok_var=1&dok_ext=htm.
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LIU, BOSUI. "VERTICALLY INTERCONNECTED WIDE-BANDWIDTH MONOLITHIC PLANAR ANTENNAS FOR 3D-IC." University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1040154281.
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Apel, Marcus. "A 3d geoscience information system framework." Doctoral thesis, Vandoeuvre-les-Nancy, INPL, 2004. https://tubaf.qucosa.de/id/qucosa%3A22479.
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Two-dimensional geographical information systems are extensively used in the geosciences to create and analyse maps. However, these systems are unable to represent the Earth's subsurface in three spatial dimensions. The objective of this thesis is to overcome this deficiency, to provide a general framework for a 3d geoscience information system (GIS), and to contribute to the public discussion about the development of an infrastructure for geological observation data, geomodels, and geoservices. Following the objective, the requirements for a 3d GIS are analysed. According to the requirements, new geologically sensible query functionality for geometrical, topological and geological properties has been developed and the integration of 3d geological modeling and data management system components in a generic framework has been accomplished. The 3d geoscience information system framework presented here is characterized by the following features: - Storage of geological observation data and geomodels in a XML-database server. According to a new data model, geological observation data can be referenced by a set of geomodels. - Functionality for querying observation data and 3d geomodels based on their 3d geometrical, topological, material, and geological properties were developed and implemented as plug-in for a 3d geomodeling user application. - For database queries, the standard XML query language has been extended with 3d spatial operators. The spatial database query operations are computed using a XML application server which has been developed for this specific purpose. This technology allows sophisticated 3d spatial and geological database queries. Using the developed methods, queries can be answered like: "Select all sandstone horizons which are intersected by the set of faults F". This request contains a topological and a geological material parameter. The combination of queries with other GIS methods, like visual and statistical analysis, allows geoscience investigations in a novel 3d GIS environment. More generally, a 3d GIS enables geologists to read and understand a 3d digital geomodel analogously as they read a conventional 2d geological map.
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Amaral, Jonatas Bussador do. "Células MCF-7 como modelo 3D no estudo de câncer de mama humano." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/42/42134/tde-21072011-134443/.
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O diferencial da cultura de células em 3-dimensões é permitir que as células explorem as 3-dimensões do espaço, aumentando assim as interações com o ambiente e entre as células. Em estudos relacionados à biologia do câncer de mama, vem ganhando espaço a utilização de esferóides para estudos que visam à compreensão da morfogênese do espaço luminal. Neste trabalho foi mostrado que as células MCF-7 reorganizam-se em estruturas tubulares e acinares. Em ambas as situações, a formação do lúmen veio acompanhada pelo estabelecimento de uma camada de células polarizadas, arranjo este muito semelhante ao encontrado em glândulas mamárias. Os resultados apresentados apontam para a existência de uma população de células na linhagem MCF-7 que não estão totalmente comprometidas ao fenótipo tumoral. Mantidos diferenciados, os esferóides de células MCF-7 apontam como um novo modelo para estudos relacionados à formação do lúmen, permitindo assim explorar o papel de diferentes vias como as relacionadas a apoptose, autofagia, diferenciação e sobrevivência celular.As a particularity, a 3D cell culture permits cells to explore the three dimensions of the space thereby increasing cell-cell interactions, as well as interaction with the environment. In studies related to breast cancer biology, spheroids are becoming widely used in the aim to comprehend luminal space morphogenesis. We showed that MCF-7 cells reorganize themselves in tubular and acinar structures. In both situations, lumen formation was accompanied by the establishment of a layer of polarized cells, an arrangement that is very similar to that of breast glands. The presented results suggest the existence of an MCF cell line population not completely committed to the tumor phenotype. When maintained as differentiated, MCF-7 cell spheroids can be a new model for studies regarding lumen formation, thereby exploring the role of diiferent pathways, such as those related to cell apoptosis, autophagy, differentiation and survival.
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Launay, Laurent. "Localisation et reconstruction 3D à partir d'angiographies stéréotaxiques." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL154N.
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Certaines méthodes thérapeutiques, telles que l'irradiation des malformations arterio-veineuses (MAVs) par radiothérapie, nécessitent de placer un cadre de stéréotaxie sur le crane du patient, afin de connaitre la position tridimensionnelle de la pathologie avec une extrême précision. Cette thèse propose une méthodologie permettant d'obtenir des reconstructions tridimensionnelles à partir de plusieurs séquences d'angiographie acquises en conditions stéréotaxiques, pour différentes incidences d'un appareil biplan. Dans un premier temps, le problème des distorsions géométriques provoquées par l'intensificateur d'images radiologiques est abordé et la précision d'une méthode de correction est quantifiée. Les techniques permettant d'estimer la géométrie d'acquisition des projections à partir des marqueurs fiduciaires du cadre de stéréotaxie sont ensuite présentées et évaluées. Une nouvelle méthode est proposée afin d'estimer la géométrie dans une gamme particulière d'incidences. Dans un second temps, la reconstruction tomographique d'une image tridimensionnelle des vaisseaux à partir d'un faible nombre de projections angiographiques est envisagée. Plusieurs méthodes algébriques de reconstruction sont comparées grâce à des simulations, et un algorithme flexible, inspiré d'une méthode d'interpolation discrète appelée DSI (Discrete Smooth Interpolation) est présenté. Une contrainte spécifique, visant à supprimer le fond en cours de reconstruction, est aussi proposée dans le but d'améliorer la reconstruction des vaisseaux. Finalement, des angiographies tridimensionnelles reconstruites à partir de six projections sont montrées sur plusieurs cas réels, et les algorithmes de reconstruction sont comparés. Une méthode permettant d'estimer l'enveloppe 3D d'une MAV à partir de contours définis sur les projections est aussi proposée, et l'intérêt de la fusion de ces données reconstruites avec une image volumique IRM du même patient est montré
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Matysczok, Carsten. "Dynamische Kantenextraktion : ein Verfahren zur Generierung von Tracking-Informationen für Augmented-Reality-Anwendungen auf Basis von 3D-Referenzmodellen /." Paderborn : HNI, 2005. http://bvbr.bib-bvb.de:8991/F?func=service&doc_library=BVB01&doc_number=014814016&line_number=0001&func_code=DB_RECORDS&service_type=MEDIA.
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Granath, Victor. "3D Printing for Computer Graphics Industry." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-10439.
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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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Nilsson, Linus. "Plug-in for stereoscopic studio production using 3Ds Max." Thesis, University of Gävle, Department of Industrial Development, IT and Land Management, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-7357.
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In this day and age when 3D cinema is ever increasing in popularity and 3D television sets on the verge of becoming a reality in our homes, the media production companies are interested in looking at how they can start producing stereoscopic format media for this exciting medium. This thesis proposes a solution to parts of the stereoscopic production pipeline by examining and proposing the extent of the requirements of a plug-in to aid in the setting up and rendering of stereo pairs and ultimately proposing such a plug-in and modifying it to suit the proposed requirements. With a high emphasis on ensuring that the plug-in is capable of producing enjoyable stereoscopic content, the plug-in is tested by rendering a demanding scene previously used in factual production work. The findings of these tests ultimately lead to the evaluation of the plug-ins usefulness as a tool for not only the production studio involved but for anyone interested in generating material for this exciting medium.
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Drobniewski, Michael. "Integration geodätischer und geotechnischer Beobachtungen und Strukturinformationen für eine 3D-Strainanalyse." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-6966750.
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Für die geodätische Überwachung dreidimensionaler Objekte fehlen in der Regel Informationen zur vollständigen Beschreibung der räumlichen Deformation. Um dieses Informationsdefizit zu beheben, können geotechnische Beobachtungen genutzt werden. In der Dissertation wird die Integration dieser Relativmessungen durch ein erweitertes Krigingverfahren gelöst. Dazu werden für den Signal- und Trendanteil der Beobachtungen die nötigen Kovarianz- und Trendmatrizen hergeleitet. Darüberhinaus wird durch die Darstellung der Beobachtungen als lineare Funktionale des Verschiebungsfeldes die Möglichkeit eröffnet, nicht nur das Verschiebungsfeld zu schätzen sondern auch beliebige lineare Funktionale des Verschiebungsfeldes. Das hergeleitete Verfahren wird an zwei praktischen Beispielen demonstriert.
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Fontbona, Joaquín. "Approches probabilistes d'un modèle d'interaction singulière et de l'équation de navier-stokes en dimension trois." Paris 6, 2004. http://www.theses.fr/2004PA066389.
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Alavi, Panah Seyed Sadroddin. "Does The Third-Dimension Play A Role in Shaping Urban Thermal Conditions?" Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/19756.
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Zahlreiche Studien den Stand der Forschung in Bezug auf die Ökosystemdienstleistungen untersucht. Dennoch wurde die Dimension „Volumen und Höhe“, d.h. die dritte Dimension städtischer Systeme, in den Studien zu Ökosystemdienstleistungen in städtischen Gebieten ignoriert. Die Forschungsziele und Fragestellungen dieser Dissertation lauten: i) Stand der aktuellen Forschung zur dritten Dimension von Ökosystemdienstleistungen im städtischen Raum, ii) Beurteilung des Zusammenhangs von urbanen mehrdimensionalen Indikatoren (zwei- und dreidimensionalen Indikatoren) für die Oberflächentemperatur in der Stadt und iii) Unterschiede zwischen Innen- und Außentemperaturen in urbanen Räumen. Diese Dissertation ist in vier Kapitel gegliedert. Im ersten und zweiten Kapitel werden die Forschungslücken und das Ziel der vorliegenden Untersuchung erläutert. Kapitel 3 enthält die veröffentlichten Artikel. Das letzte Kapitel behandelt die Ergebnisse der veröffentlichten Artikel. Diese Dissertation betont die Bedeutung von dreidimensionalen Studien in urbanen Ökosystemen, um das Konzept der Nachhaltigkeit in Städten voranzutreiben. Deshalb werden kontinentübergreifende Forschungen für weitere Studien empfohlen, die die dreidimensionale Struktur aller städtischen Komponenten und ihre Auswirkungen auf die Außen- und Innentemperatur berücksichtigen.Among the studies on ecosystem services undertaken in urban areas, a dimension ‘volume and height’, i.e., the third-dimension of urban environment is largely ignored. More specific, three-dimensional spatial models will increase the knowledge of how complex environment shape the micro-climate in urban environment. The research objectives and questions of this dissertation is: i) the status of the current research addressing the third-dimension of ecosystem services in urban area, ii) assessing the association of urban multi-dimensional (two- and three- dimensional) indicators on urban surface temperature and iii) variation of indoor and outdoor urban temperature pattern. This dissertation is organized into four chapters. The first and second chapter explain the gaps in literature and the aim of this research. Chapter 3 holds the published articles. The last chapter discusses the results of the published articles. This dissertation emphasizes the importance of three-dimensional studies in urban ecosystems to advance the concept of sustainability in cities. Therefore, cross-continental studies that consider the three-dimensional structure of all the urban components and its impact on outdoor and indoor temperature is recommended for future research.
به جرات می توان گفت که در مطالعات خدمات اکوسیستم، بخصوص خدمات اکوسیستم شهری ، بعد سوم که شامل "ارتفاع و حجم" می باشد اصلا مورد توجه قرار نگرفته است. هدف از این پایان نامه، تلفیق مفهوم بعد سوم در خدمات اکوسیستم شهری و استفاده از فواید آن می باشد. مطالعه بعد سوم دانش ما را در نحوه شکل گیری اقلیم خُرد شهری افزایش می دهد. هدف این پروژه دکتری پاسخ به سوالات ذیل می باشد: 1) سطح آگاهی تحقیقات از بعد سوم خدمات اکوسیستم شهری، 2) ارزیابی ارتباط شاخص های چندبعدی (دو و سه بعدی) با دمای سطح و 3) ارزیابی الگوی دمای درونی و بیرونی در شهر. جهت پاسخ دادن به سوال های مطرح شده، این پژوهش به چهار فصل تقسیم شده است. فصل اول و دوم، که جایگاه خدمات اکوسیستم را در مطالعات شهری بررسی و جای خالی مفهوم بعد سوم در مطالعات خدمات اکوسیستم شهری را جستجو می کند. فصل سوم، شامل سه مقاله چاپ شده در راستای این پروژه دکتری می باشد. فصل چهارم، که نتایج بدست آمده را تجزیه و تحلیل می کند. نتایج بدست آمده نشان می دهد که مطالعات خدمات اکوسیستم شهری از معنی کلی و بنیادی به سمت سازش پذیری شهرها با پدیده تغییر اقلیم در حال تغییر است. همچنین نتایج نشان می دهد که ساختار متفاوت شهری بر شکل گیری الگوی دمای بیرون و داخل ساختمان ها موثر می باشد. استنتاج نتایج بدست آمده از این پایان نامه دو مورد را پیشنهاد می کند. اول، بررسی نقش ساختار های دو بعدی و سه بعدی بر روی دیگر شهر ها و تاثیر آن بر شکل گیری دمای بیرون و درونی ساختمان ها.
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Sysavath, Vithoone. "Waldmonitoring unter besonderer Berücksichtigung der aus Stereoluftbildern abgeleiteten 3. Dimension." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:swb:105-5999892.
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Results of the investigation has been presented to derive digital elevation models of forest areas for the determination of the parallax measuring accuracy from AATE (Adaptive Automatic Terrian Extraction) with the PCI software Geomatica. It has been used the informations from the threefold overlaps of aerial stereoscopic pairs. The parallax measuring errors on forest areas are three times larger than on the arable and pasturelands. It has been shown that the third dimension can be used for the derivative of crown of tree profiles and their roughness and the rates of timber growth can be derived with sufficiently high accuracy from the repeatability flying.
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Söderberg, Alexander. "Anomalous Dimensions in the WF O(N) Model with a Monodromy Line Defect." Thesis, Uppsala universitet, Teoretisk fysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-317546.
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General ideas in the conformal bootstrap program are covered. Both numerical and analytical approaches to the bootstrap equation are reviewed to show how it can be manipulated in different ways. Further analytical approaches are studied for theories with defects. We consider the three-dimensional CFT at the corresponding WF fixed point in the O(N) \phi^4 model with a co-dimension two, monodromy defect. Anomalous dimensions for bulk- and defect-local fields as well as one of the OPE coefficients are found to the first loop order. Implications of inserting this defect and constraints that arises from symmetries of the theory are investigated.
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Hua, Xiaoben, and Yuxia Yang. "A Fusion Model For Enhancement of Range Images." Thesis, Blekinge Tekniska Högskola, Sektionen för ingenjörsvetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-2203.
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In this thesis, we would like to present a new way to enhance the “depth map” image which is called as the fusion of depth images. The goal of our thesis is to try to enhance the “depth images” through a fusion of different classification methods. For that, we will use three similar but different methodologies, the Graph-Cut, Super-Pixel and Principal Component Analysis algorithms to solve the enhancement and output of our result. After that, we will compare the effect of the enhancement of our result with the original depth images. This result indicates the effectiveness of our methodology.Room 401, No.56, Lane 21, Yin Gao Road, Shanghai, China
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Lottin, Delphine. "Dimensions fractales, morphologie et caractéristiques dimensionnelles 2D et 3D d'agrégats de nanoparticules de suie aéronautique : Etude par microscopie électronique en transmission et tomographie électronique." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4012/document.
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Les agrégats de suie émis par les processus de combustion dans les turbines aéronautiques contribuent à modifier le bilan radiatif de l'atmosphère et la qualité de l'air. La connaissance de leurs caractéristiques physiques et chimiques est indispensable pour évaluer leur rôle dans les processus physico-chimiques atmosphériques et leur impact sur l'environnement et la santé publique. Dans ce contexte, notre étude vise à déterminer la taille et la morphologie d'agrégats de suie aéronautique à partir de mesures expérimentales menées en microscopie électronique en transmission (MET) et en tomographie électronique.Nous avons réalisé des clichés MET d'agrégats de suie émis par des turboréacteurs aéronautiques. Nous avons établi une méthode pour caractériser la morphologie des agrégats en déterminant leur allongement, leur compacité et la tortuosité de leur contour en analysant leur projection. Nous avons également développé un logiciel de traitement et d'analyse des images MET qui permet de reconstruire en 3D un agrégat à partir de ses projections et l'analyse de ses caractéristiques dimensionnelles et morphologiques à partir de sa reconstruction. Les résultats obtenus nous ont permis d'étudier la validité des relations liant les caractéristiques microphysiques 2D et 3D proposées dans la littérature et d'en proposer de nouvelles pour les agrégats étudiés.Ces résultats constituent la première caractérisation morphologique 3D d'agrégats de suie aéronautique à partir d'analyses par MET et tomographie électronique. Ils montrent que les propriétés morphologiques de ces agrégats ne permettent pas d'utiliser la méthode d'ensemble pour déterminer la dimension fractale massiqueSoot aggregates emitted by aircraft engines' combustion processes are involved in the modification of the global radiative budget and the air quality. The knowledge of their physical and chemical characteristics is a prerequisite to any evaluation of the way they may act in the atmospheric physical and chemical processes and their impact on the environment and public health. In this context, our study aims at determining the size and morphological characteristics of aircraft soot aggregates on the basis of experimental measurements by transmission electron microscopy (TEM) and electron tomography.We have acquired TEM pictures of soot aggregates emitted by aircraft engines. We have established a method to characterize the morphology of these aggregates by determining their elongation, their compacity and the tortuosity of their edge. This method is based on the analysis of their TEM projection. Besides, we have developed a software to process and analyse TEM pictures. It allows to reconstruct aggregates from their projections and to determine their size and morphological characteristics. Our results have lead us to study the validity of the relationships linking the 2D and 3D microphysical characteristics presented in the literature and to suggest new ones for the studied aggregates.These results constitute the first 3D morphological and size characterizations of aircraft soot aggregates using TEM and electron tomography. They highlight the fact that the morphological properties of these aggregates do not fulfil the hypotheses required for the use of the collective method to determine the mass fractal dimension
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Wilhelms, Wenke. "Development of a three-dimensional all-at-once inversion approach for the magnetotelluric method." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2016. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-207548.
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A three-dimensional inversion was implemented for magnetotellurics, which is a passive electromagnetic method in geophysics. It exploits natural electromagnetic fields of the Earth, which function as sources. Their interaction with the conductive parts of the subsurface are registered when components of the electric and the magnetic field are measured and evaluated.
The all-at-once approach is an inversion scheme that is relatively new to geophysics. In this approach, the objective function – the basis of each inversion – is called the Lagrangian. It consists of three parts: (i) the data residual norm, (ii) the regularisation part, and (iii) the forward problem. The latter is the significant difference to conventional inversion approaches that are built up of a forward calculation part and an inversion part. In the case of all-at-once, the forward problem is incorporated in the objective function and is therefore already taken into account in each inversion iteration. Thus, an explicit forward calculation is obsolete. As an objective function, the Lagrangian shall reach a minimum and therefore its first and second derivatives are evaluated. Hence, the gradient of the Lagrangian and its Hessian are constituent parts of the KKT system – the Newton-type system that is set up in the all-at-once inversion. Conventional inversion approaches avoid the Hessian because it is a large, dense, not positive definite matrix that is challenging to handle. However, it provides additional information to the inversion, which raises hope for a high quality inversion result.
As a first step, the inversion was programmed for the more straightforward one-dimensional magnetotelluric case. This was particularly suitable to become familiar with sQMR – a Krylov subspace method which is essential for the three-dimensional case to be able to work with the Hessian and the resulting KKT system. After the implementation and validation of the one-dimensional forward operator, the Lagrangian and its derivatives were set up to complete the inversion, which successfully solved the KKT system. Accordingly, the three-dimensional forward operator also needed to be implemented and validated, which was done using published data from the 3D-2 COMMEMI model. To realise the inversion, the Lagrangian was assembled and its first and second derivatives were validated with a test that exploits the Taylor expansion. Then, the inversion was initially programmed for the Gauss-Newton approximation where second order information is neglected. Since the system matrix of the Gauss-Newton approximation is positive definite, the solution of this system of equations could be carried out by the conventional solver pcg. Based on that, the complete KKT system (Newton\\\'s method) was set up and preconditioned sQMR solved this system of equations.
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Knust, Claudia. "Untersuchungen zur Gestaltung kartographischer Inhalte auf autostereoskopischen Monitoren." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-210590.
Full textAbstract:
Autostereoskopische Monitore ermöglichen das spontane dreidimensionale Betrachten des gezeigten Inhaltes, ohne dass zusätzliche Betrachtungshilfen notwendig sind. Eine solche räumliche Wahrnehmung kann auch für die Kartographie vielfaltige neue Visualisierungsmöglichkeiten bieten. Allerdings wurden dafür bisher kaum Gestaltungsregeln formuliert. Gerade das ist aber notwendig, um das Potential dieser 3D-Monitore richtig nutzen zu können. Die vorliegende Arbeit befasst sich mit der Gestaltung kartographischer Inhalte auf autostereoskopischen Monitoren und soll damit einen Beitrag leisten, solche Monitore in naher Zukunft optimal für kartographische Zwecke einsetzen zu können. Nach der Beschreibung des Forschungsstandes hinsichtlich 3D-Visualisierungstechniken und Minimaldimensionen kartographischer Inhalte an Monitoren behandelt die vorliegende Arbeit zwei empirische Untersuchungen. Im ersten Teil werden verschiedene graphische Elemente hinsichtlich ihrer Mindestgröße untersucht. Angelehnt an bereits vorhandene Empfehlungen für 2D-Monitore sowie Untersuchungen an gedruckten Lentikulardisplays werden Schrift, Linien und einfache Zeichen verschiedener Größe bzw. Strichstarke bezüglich ihrer Lesbarkeit an einem Lentikularmonitor getestet. Um eine Mindestgröße sinnvoll festzulegen, soll hierbei das Kriterium erfüllt sein, dass 90 % der Befragten die gezeigten Wörter, Linien bzw. Zeichen in mindestens dieser Größe lesen konnten. Neben den Mindestgrößen wird in dieser ersten Studie zudem die Erkennbarkeit und Unterscheidbarkeit von verschiedenen Tiefenebenen untersucht. Anhand von Positionssignaturen, die sich blockweise in unterschiedlichem Abstand zum Betrachter befinden, d.h. in verschiedenen Tiefenebenen liegen, wird ermittelt, ob und wie gut eine Unterscheidung dieser Ebenen möglich ist. Insgesamt werden in dieser ersten Studie neun Hypothesenpaare überprüft. Die zweite empirische Untersuchung, die in dieser Arbeit vorgestellt wird, befasst sich mit der Wahrnehmungsleistung in thematischen Karten an 2D-Monitoren und an 3D-Monitoren. Anhand von einfach gestalteten thematischen Karten werden die Antwortzeit und die Antwortgenauigkeit bei der Lösung einfacher Aufgaben analysiert. Getestet wird an dem gleichen Monitor, der bereits für die Untersuchung zu den Minimaldimensionen genutzt wurde und vergleichend dazu an einem ähnlich großen 2D-Monitor. In dieser zweiten Studie werden zwei Hypothesenpaare überprüft. Darüber hinaus werden die Ergebnisse mit einer parallel am Geografischen Institut der Ruhr-Universität Bochum stattgefundenen Studie verglichen. Die Projektpartner testeten unter sehr ähnlichen Bedingungen einen zweiten Lentikularmonitor. Anhand des Vergleichs beider Studien werden erste Schlussfolgerungen gezogen, die für eine Gestaltung kartographischer Inhalte an Lentikularmonitoren im Allgemeinen gültig sind. Die Ergebnisse der ersten Untersuchung zeigen, dass die Minimaldimensionen von Schrift, Linien und einfachen Zeichen am untersuchten 3D-Monitor weniger stark von den Empfehlungen für normale 2D-Monitore abweichen als im Vorfeld vermutet wurde. Bei der zweiten Studie hingegen lässt sich anhand der untersuchten thematischen Karte hinsichtlich der Wahrnehmungsleistung schlussfolgern, dass eine Visualisierung am 3D-Monitor zwar keine Verbesserung der Antwortgenauigkeit bewirkt, wohl aber eine deutliche Reduzierung der Antwortdauer. In der zweiten empirischen Untersuchung liegen Daten zu weiteren Testkarten vor, die die in dieser Arbeit vorgestellten Ergebnisse verifizieren konnten. In weiterer Analysearbeit sollen diese Erkenntnisse in naher Zukunft zur Verfügung gestellt werden. Darüber hinaus wird empfohlen, die Untersuchungen auf verschiedene 3D-Monitore auszuweiten, um eine Allgemeingültigkeit der ermittelten Erkenntnisse verifizieren zu können bzw. um detailliertere Empfehlungen zur Gestaltung thematischer Inhalte auf 3D-Monitoren geben zu könnenAutostereoscopic monitors allow spontaneous three-dimensional perception of the visualised content without the need of any additional viewing aids. Such a kind of spatial perception can also allow multiple new visualisation options in the field of cartography. So far, there are hardly any rules given for an optimal design of such cartographic visualisations. But, this is essential in order to use the potential of these 3D monitors correctly. Therefore, this work deals with the design of cartographic content on autostereoscopic monitors. Thus, it shall contribute to an optimal use of such a monitor for cartographic purposes in the near future. After describing the state of research regarding 3D visualisation techniques and minimum dimensions of cartographic content on monitors in general, the present work discusses two empirical studies. In the first study, several graphic elements are analysed regarding their minimal legible size. Some lettering, lines and simple symbols are tested regarding their legibility on a monitor which uses the lenticular foil technology. The test patterns are based on existing recommendations for 2D monitors and studies on printed lenticular foil displays. A simple rule was chosen to be able to specify minimum sizes for the tested elements: at least 90 % of the test persons have been able to read the test words, lines or symbols in this size. Furthermore, the first study investigated the ability to differentiate several depth planes. With the help of point symbol blocks which are located in different distances to the viewer, i.e. which are located in different depth planes, it is examined if the participants can differentiate these planes easily. Altogether, nine pairs of hypotheses are analysed during this study. The second empirical study which is presented in this work, deals with the map reading performance in thematic maps visualised on 2D monitors and on 3D monitors. Using thematic maps of simple design the response time and response accuracy are analysed for solving simple map reading tasks. The used 3D monitor was the same as for the first study. Further, the same questions were asked for the thematic maps shown on a normal 2D monitor with nearly the same size as the 3D monitor. In this second study two pairs of hypotheses are analysed. Moreover, the findings are compared with a similar study which was conducted at the Geographic Institute of the Ruhr University Bochum. The project partners tested the thematic maps on a second lenticular monitor under very similar conditions. Based on a comparison of both studies an attempt will be made to draw some conclusions that are generally valid for a design of cartographic content on lenticular monitors. The results of the first study show that for the examined 3D monitor the minimum dimensions of lettering, lines and simple symbols differ less from the recommendations for normal 2D monitors than assumed before the studies. The findings of the second study for map reading efficiency on thematic maps show that the visualisation on a 3D monitor reduces the response time of the questions. However, the correctness of the answers does not improve between the 2D monitor and the 3D monitor. In the second empirical study data of more test maps than used in this work is available. It shall be used in further analyses for trying to verify the results presented here. In addition, it is recommended to extend the studies on different 3D monitors to verify a general applicability of the findings or to give more detailed recommendations for the design of thematic content on 3D monitors
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Schütz, Rosvita. "Aplicação do sensoriamento remoto na roteirização turística na encosta nordeste do planalto meridional do Rio Grande do Sul, RS. Estudo de caso: município de Três Cachoeiras." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17896.
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O turismo tem apresentado uma demanda mundial cada vez maior e, por conseguinte, há uma crescente necessidade de preservar o meio ambiente com vistas às gerações futuras. O geoturismo e a roteirização, são ferramentas que podem ser utilizadas para este fim. Este trabalho visa, portanto, integrar dados turísticos, através do Sensoriamento Remoto com dados altimétricos representados por um Modelo Digital de Elevação - MDE. Desta forma, esta sistemática permite desenvolver um ambiente virtual onde o usuário pode realizar vôos cênicos em 3D (terceira dimensão) sobre o município de Três Cachoeiras e realizar, com isso um planejamento eficaz de suas atividades turísticas antes mesmo de ir a campo. Com a imagem de alta resolução espacial IKONOS (1m) sobreposta ao MDE é possível caracterizar a região e definir critérios, como por exemplo, a declividade do terreno para avaliar cada percurso. Estas ferramentas permitem, portanto, o estabelecimento de critérios de deslocamento e aos níveis de dificuldade para cada percurso. Os dados de campo, bem como aqueles provenientes da análise das imagens orbitais e do MDE, resultaram em uma roteirização turística sobre dois temas distintos: o Geoturismo e o Turismo Rural.The tourism has presented a world-wide demand (2008). Representing an increasing necessity to preserve the environment with sights to the future generations, by the geotourism and the route planning, as well as the scientific research. This work aims at, therefore, to integrate tourist and de Remote sensing with altimetric data, represented by a Digital Elevation Model - DEM. In such a way, this systematics, allows to develop a virtual environment where the user can to visualize through scenic flights in 3D (third dimension) the city of Três Cachoeiras and make an efficient planning of tourist activities before exactly to go the field. With high resolution space image IKONOS (1m) overlapped to the DEM, is possible to characterize the region and to define criteria, as for example, the declivity of the land for evaluate each passage. These tools allow the establishment of criteria of displacement and the levels of difficulty for each passage. The field data, as well as those proceeding from the analysis of the orbital images and the DEM, had resulted in a touristic route on two distinct subjects: the Geotourism and the Rural Tourism.
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Dupas, Alexandre. "Opérations et Algorithmes pour la Segmentation Topologique d'Images 3D." Phd thesis, Université de Poitiers, 2009. http://tel.archives-ouvertes.fr/tel-00466706.
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Une carte topologique 3D est un modèle servant à représenter la partition en régions d'une image 3D pour le traitement d'images. Dans ce travail, nous développons des outils permettant de modifier la partition représentée par une carte topologique, puis nous utilisons ces outils afin de proposer des algorithmes de segmentation intégrant des critères topologiques. Dans une première partie, nous proposons trois opérations. La fusion de régions est définie avec une approche locale adaptée à une utilisation interactive et une approche globale pour une utilisation automatisée comme lors d'une segmentation. La division de régions est proposée avec une méthode d'éclatement en voxels et la division à l'aide d'un guide. Enfin, la déformation de la partition est basée sur la définition de points ML-Simples : des voxels pouvant changer de région sans modifier la topologie de la partition. À l'aide de ces opérations, nous mettons en œuvre dans une seconde partie des algorithmes de segmentation d'images utilisant les cartes topologiques. Notre première approche adapte au modèle des cartes topologiques un algorithme existant qui utilise un critère basé sur la notion de contraste. Nous proposons ensuite des méthodes de calcul d'invariants topologiques sur les régions : les nombres de Betti. Grâce à eux, nous développons un critère topologique de segmentation permettant de contrôler le nombre de tunnels et de cavités des régions. Enfin, nous illustrons les possibilités de tous nos outils en mettant en place une chaîne de traitement pour la segmentation de tumeurs cérébrales dans des images médicales.
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Vidal, Manuel. "Influence des cadres de référence sur la mémoire spatiale de trajets en trois dimensions." Paris 6, 2002. http://www.theses.fr/2002PA066368.
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Morard, Adrien. "Miniaturisation et fiabilité des interconnexions copper pillar sur desassemblages de type « System In Package » (sip) pour le domaine aéronautique." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAT068.
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La thèse s’inscrit dans un contexte d’ouverture vers de nouvelles solutions techniques. L’objectif quiest porté par cette étude est double, le premier est de miniaturiser l’électronique pour atteindre un gaind’un facteur 10 en intégration par rapport à une technologie CMS classique, le second est d’améliorer lafiabilité des assemblages de type « System In Package » ainsi obtenus pour les domaines aéronautique,défense et spatial.La première phase de travail concerne la fabrication d’un assemblage composé d’une puce en siliciumet d’un substrat organique. Ces deux entités permettront l’étude du report par flip chip. Pour ce faire, desconnexions de type micro-piliers en cuivre et en alliage étain-argent, autrement appelées « copper pillar »seront mises en place. L’impact des différents paramètres de conception et d’assemblage sur la fiabilité encycles thermiques seront étudiés.Dans une seconde phase, des simulations par éléments finis sont effectuées sur les assemblages afind’obtenir des prédictions sur la fiabilité au cours de cycles thermiques en utilisant comme critère l’énergieviscoplastique. Les simulations et les résultats expérimentaux seront finalement comparés et les écartsseront discutés.L’analyse de défaillances au cours des cycles thermiques reposera sur l’analyse des interconnexions« copper pillar » par micro-sections et imagerie SEM et EBSD. Les évolutions d’épaisseur d’intermétalliques,des fissurations dans la brasure ainsi que la taille des grains et les phénomènes de recristallisation serontprésentés et commentés.Les objectifs finaux de ce travail sont, d‘un point de vue académique, de mettre en lumière toutd’abord, les comportements mis en jeu dans la fiabilité de telles interconnexions dans un environnementthermo-mécanique contraignant, et, par ailleurs, les mécanismes de défaillance. Ensuite, il s’agit d’établirun modèle de vieillissement qui soit représentatif des résultats expérimentaux obtenus. Enfin, il s’agira dedéfinir des règles de conception qui pourront ensuite être utilisées au niveau de Safran pour la réalisationdes assemblages SIP intégrés dans des systèmes embarquésThe thesis is opening towards new technical solutions. The aim of this study is twofold, the first is tominiaturize the electronics to achieve a factor of 10 in integration compared to a conventional CMStechnology, the second is to improve the system in package reliability for aeronautics, defense and space.The first step concerns the manufacture of an assembly composed by a silicon chip and an organicsubstrate. These two entities will allow the study of the report by flip chip. To do so, micro-pillar type copperand tin-silver solder connections, otherwise known as copper pillar, will be used. The impact of differentdesign and assembly parameters on thermal cycles reliability will be studied.In a second step, finite element simulations are carried out on the assemblies in order to obtainpredictions on the reliability during thermal cycles using as a criterion the viscoplastic energy. Thesimulations and the experimental results will eventually be compared, and the gaps will be discussed.Failures analysis during thermal cycles will be based on the analysis of copper pillar interconnectionsby micro-sections and SEM and EBSD imaging. Thickness changing in intermetallic, cracking in the solder aswell as grain size and recrystallization phenomena will be presented and commented.The final objectives of this work are, from an academic point of view, to highlight first of all, theC2 - Restrictedbehaviors involved in the reliability of such interconnections in a binding thermo-mechanical environment,and moreover, the failure mechanisms. Then, it is to establish a predict life model that is representative ofthe experimental results obtained. Finally, it will define design rules that can then be used at Safran for therealization of SIP
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Bertin, Etienne. "Diagrammes de Voronoï 2D et 3D : applications en analyse d'images." Grenoble 1, 1994. http://tel.archives-ouvertes.fr/tel-00005078.
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Cette thèse est axée sur la coopération entre l'analyse d'images et la géométrie algorithmique sur la base des diagrammes de Voronoi et de Delaunay. Le propos de l'analyse d'images est la description du contenu d'une image, en vue de son interprétation et d'une prise de décision. La géométrie algorithmique quant à elle consiste à trouver des algorithmes efficaces en vue de résoudre des problèmes a caractère géométrique. Nous nous intéresserons ici au problème de représentation des images par des partitionnements plus ou moins complexes, adaptes ou non au contenu informatif des images. Parmi ces partitionnements, nous développerons plus particulièrement celui en régions de Voronoi. Nous aborderons ensuite le problème du codage de formes tridimensionnelles par leur squelette qui est lié aux diagramme de Voronoi généralisé 3D. Nous montrerons enfin comment utiliser les partitionnements en région de Voronoi dans un contexte pyramidal contrôlé par un réseau de Hopfield en vue de la segmentation, et dans un contexte markovien en vue de trouver un partitionnement répondant a une certaine optimalité
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JOHANSSON, ANNA. "3D-2D-3D." Thesis, Högskolan i Borås, Institutionen Textilhögskolan, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-18108.
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The area of this work is a combination of draping and printing. It strives towards the technique that dazzles the eye with illusions of more than one dimension. As a viewer you will believe that the prints are real drapings while they are flat surfaces. Today prints in fashion are categorized as placed prints or all-over prints, and generally created as a flat surface to decorate the garments. In this work the idea is to manipulate and challenge the boundaries of print and give it life through the body shapes and in the movement. Potentially this work could be an introduction to a new way of working with prints in fashion. This work could poosibly be presented as a new technique where placed- print and all-over prints comes together- called placed all-over prints. Also, it could develop into further techniques in using two-dimensional flatness and save fabric in using photography as an option to the real three-dimensional drapings. Furthermore could it mean savings in material as a conscious choice in the process ? This investigation explores two particular kinds of techniques, - print and draping, that are merged into one expression. The aims of this work is to find new ways of using print in combination with draping in dress and explore the possibilities to find a new technique to create interesting womenswear. To unite dimensions like two-dimensional and three-dimensional as a method of finding new forms and expressions. Through experiments with striped textiles the focus is to investigate the possibilities of greater visual effects on two-dimensional prints. For a depth and to exaggerate the directions in the fabric before translating it into a flat surface the striped textile can be a tool for further design. The striped textile has the potential to help the eye to understand the directions in the print and can be used in more than one dimension and color. To explore how to create 3D effect on 2D in print design through draping in dress is the aim of this work.Program: Modedesignutbildningen
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Evans, Sam. "3D imaging in forensic odontology." Thesis, University of South Wales, 2012. https://pure.southwales.ac.uk/en/studentthesis/3d-imaging-in-forensic-odontology(e836ce64-0279-452d-bf6b-d10c2ec09a21).html.
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This work describes the investigation of a new 3D capture method for acquisition and subsequent forensic analysis of bite mark injuries on human skin. When documenting bite marks with standard 2D cameras, errors in photographic technique can occur if best practice is not followed. Subsequent forensic analysis of the mark is problematic when a 3D structure is recorded in a 2D space. A 3D image capture and processing system might avoid the problems resulting from the 2D reduction process, simplifying the guidelines and reducing errors. The proposed solutions in this work are: conducting a review of the current 2D and three 3D capture methods, also a series of benchmarks for system assessment. Followed by a series of performance evaluations of the existing current 2D and two 3D methods. Further proposed solutions include, the design of a system specification for the practical reproducible acquisition of bite mark injuries. Finally a review of the validation process for forensic evidence presented to the courts. The results of the work are as follows: A 3D system is required to produce the correct 3D data of a bite mark and suspect dentition for forensic analysis. Such a system should be practical and consistent, if it is to replace the current de facto 2D systems. The MAVIS hardware can be considered a practical and consistent solution for producing the required 3D image of a bite mark for analysis; however, the MAVIS hardware cannot produce a satisfactory 3D image of a dental cast. At present a laser scanner is required to produce satisfactory results of a dental cast. Angular distortion and errors created by the user in 2D image capture can hinder the digital measurement process. 3D capture therefore introduces less operator error in the form of angular distortion.
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Han, Ching-Pei B. "3D alchemy : a guide to 3D realistic computer graphics /." Online version of thesis, 1993. http://hdl.handle.net/1850/11747.
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Tian, Kehan. "Three dimensional (3D) optical information processing." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/35627.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2006.Includes bibliographical references (p. 141-151).
Light exhibits dramatically different properties when it propagates in or interacts with 3D structured media. Comparing to 2D optical elements where the light interacts with a sequence of surfaces separated by free space, 3D optical elements provides more degrees of freedom to perform imaging and optical information processing functions. With sufficient dielectric contrast, a periodically structured medium may be capable of forbidding propagation of light in certain frequency range, called band gap; the medium is then called a photonic crystal. Various "defects", i.e. deviations from perfect periodicity, in photonic crystals are designed and widely used as waveguides and microcavities in integrated optical circuits without appreciable loss. However, many of the proposed waveguide structures suffer from large group velocity dispersion (GVD) and exhibit relatively small guiding bandwidth because of the distributed Bragg reflection (DBR) along the guiding direction. As optical communications and optical computing progress, more challenging demands have also been proposed, such as tunable guiding bandwidth, dramatically slowing down group velocity and active control of group velocity. We propose and analyze shear discontinuities as a new type of defect in photonic crystals.
(cont.) We demonstrate that this defect can support guided modes with very low GVD and maximum guiding bandwidth, provided that the shear shift equals half the lattice constant. A mode gap emerges when the shear shift is different than half the lattice constant, and the mode gap can be tuned by changing the amount of the shear shift. This property can be used to design photonic crystal waveguides with tunable guiding bandwidth and group velocity, and induce bound states. The necessary condition for the existence of guiding modes is discussed. By changing the shape of circular rods at the shear interface, we further optimize our sheared photonic crystals to achieve minimum GVD. Based on a coupled resonator optical waveguide (CROW) with a mechanically adjustable shear discontinuity, we also design a tunable slow light device to realize active control of the group velocity of light. Tuning ranges from arbitrarily small group velocity to approximately the value of group velocity in the bulk material with the same average refractive index. The properties of eigenstates of tunable CROWs: symmetry and field distribution, and the dependence of the group velocity on the shear shift are also investigated.
(cont.) Using the finite-difference time-domain (FDTD) simulation, we demonstrate the process of tuning group velocity of light in CROWs by only changing the shear shift. A weakly modulated 3D medium diffracts light in the Bragg regime (in contrast to Raman-Nath regime for 2D optical elements), called volume hologram. Because of Bragg selectivity, volume holograms have been widely used in data storage and 3D imaging. In data storage, the limited diffraction efficiency will affect the signal-noise-ratio (SNR), thus the memory capacity of volume holograms. Resonant holography can enhance the diffraction efficiency from a volume hologram by enclosing it in a Fabry-Perot cavity with the light multiple passes through the volume hologram. We analyze crosstalk in resonant holographic memories and derive the conditions where resonance improves storage quality. We also carry out the analysis for both plane wave and apodized Gaussian reference beams. By utilizing Hermite Gaussian references (higher order modes of Gaussian beams), a new holographic multiplexing method is proposed - mode multiplexing.
(cont.) We derive and analyze the diffraction pattern from mode multiplexing with Hermite Gaussian references, and predict its capability to eliminate the inter-page crosstalk due to the independence of Hermite Gaussian's orthogonality on the direction of signal beam as well as decrease intra-page crosstalk to lower level through apodization. When using volume holograms for imaging, the third dimension of volume holograms provided more degrees of freedom to shape the optical response corresponding to more demanding requirements than traditional optical systems. Based on Bragg diffraction, we propose a new technique - 3D measurement of deformation using volume holography. We derive the response of a volume grating to arbitrary deformations, using a perturbative approach. This result will be interesting for two applications: (a) when a deformation is undesirable and one seeks to minimize the diffracted field's sensitivity to it and (b) when the deformation itself is the quantity of interest, and the diffracted field is used as a probe into the deformed volume where the hologram was originally recorded.
(cont.) We show that our result is consistent with previous derivations motivated by the phenomenon of shrinkage in photopolymer holographic materials. We also present the analysis of the grating's response to deformation due to a point indenter and present experimental results consistent with theory.
by Kehan Tian.
Ph.D.
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Hennessey, Craig. "Point-of-gaze estimation in three dimensions." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2837.
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Binocular eye-gaze tracking can be used to estimate the point-of-gaze (POG)
of a subject in real-world three-dimensional (3D) space using the vergence
of the eyes. In this thesis, a novel non-contact, model-based technique for
3D POG estimation is presented. The non-contact system allows people to
select real-world objects in 3D physical space using their eyes, without the
need for head-mounted equipment. Using a model-based POG estimation
algorithm allows for free head motion and a single stage of calibration. The
users were free to naturally move and reorient their heads while operating
the system, within an allowable headspace of 3.2 x 9.2 x 14 cm. A rela
tively high precision, as measured by the standard deviation of the 3D POG
estimates, was measured to be 0.26 cm and was achieved with the use of
high speed sampling and digital filtering techniques. When observing points
in a 3D volume, large head and eye rotations are far more common than
when observing a 2D screen. A novel corneal reflection pattern matching
algorithm is presented for increasing image feature tracking reliability in the
presence of large eye rotations. It is shown that an average accuracy of 3.93
cm was achieved over seven different subjects and a workspace volume of 30
x 23 x 25 cm (width x height x depth). An example application is presented
illustrating the use of the 3D POG as a human computer interface in a 3D
game of Tic-Tac-Toe on a 3 x 3 x 3 volumetric display.
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Liang, Chen. "3D model reconstruction from silhouettes." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/b40203311.
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Liang, Chen, and 梁晨. "3D model reconstruction from silhouettes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40203311.
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Liu, Chi Hin. "Structured lighting 3D reconstruction and 3D shape matching of human model for garment industries /." View abstract or full-text, 2006. http://library.ust.hk/cgi/db/thesis.pl?MECH%202006%20LIUC.
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Chabbi, Houda. "Construction de facettes 3D par stéréovision intégrant des principes de géométrie projective." Vandoeuvre-les-Nancy, INPL, 1993. http://docnum.univ-lorraine.fr/public/INPL_T_1993_CHABBI_H.pdf.
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Le travail présenté dans ce mémoire s'inscrit dans le cadre de la vision artificielle et l'objectif recherche est de développer un processus de reconstruction stéréoscopique des facettes 3D des scènes observées. Le principe fondamental que nous avons suivi pour réaliser la construction de facettes 3D a été d'éviter dans la mesure du possible, tout calcul direct sur les segments 3D. Nous avons alors proposé un protocole d'utilisation de l'information région et l'information contour pour construire des indices 2D: facettes 2D par l'intermédiaire desquels nous inférons l'existence d'un plan 3D. Utilisant ensuite des techniques de géométrie projective, nous vérifions en 2D la validité de l'hypothèse de planarité relative à chacun de ces indices. La recherche des paramètres de chacune des facettes 3D de la scène utilise alors toute l'information acquise en 2D concernant les propriétés 3D à vérifier par ces facettes à construire. Cette reconstruction permet ainsi de maintenir la propriété de planarité ou encore de coplanarité entre facettes améliorant la localisation 3D de ces primitives
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Davies, Colin J. "Three dimensional sensing via coloured spots." Thesis, University of Southampton, 1996. https://eprints.soton.ac.uk/253028/.
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Tan, Ping. "3D modeling from photometry and geometry /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CSED%202007%20TAN.
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Wang, Haomian. "Visualization techniques for 3D urban environments /." View abstract or full-text, 2009. http://library.ust.hk/cgi/db/thesis.pl?CSED%202009%20WANGH.
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Eren, Gönen. "3D scanning of transparent objects." Phd thesis, Université de Bourgogne, 2010. http://tel.archives-ouvertes.fr/tel-00584061.
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Many practical tasks in industry, such as automatic inspection or robot vision, often require scanning of three-dimensional shapes with non-contact techniques. However, transparent objects, such as those made of glass, still pose difficulties for classical scanning techniques. The reconstruction of surface geometry for transparent objects is complicated by the fact that light is transmitted through, refracted and in some cases reflected by the surface. Current approaches can only deal relatively well with sub-classes of objects. The algorithms are still very specific and not generally applicable. Furthermore, many techniques require considerable acquisition effort and careful calibration. This thesis proposes a new method of determining the surface shape of transparent objects. The method is based on local surface heating and thermal imaging. First, the surface of the object is heated with a laser source. A thermal image is acquired, and pixel coordinates of the heated point are calculated. Then, the 3D coordinates of the surface are computed using triangulation and the initial calibration of the system. The process is repeated by moving the transparent object to recover its surface shape. This method is called Scanning From Heating. Considering the laser beam as a point heating source and the surface of the object locally flat at the impact zone, the Scanning From Heating method is extended to obtain the surface normals of the object, in addition to the 3D world coordinates. A scanner prototype based on Scanning From Heating method has been developed during the thesis.
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Taylor, Ian. "'Dynamic scaling for three-dimensional information visualisation'." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324478.
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Bakos, George Christos. "Three-dimensional (3D) acoustic and vision systems." Thesis, University of Liverpool, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245468.
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Sardouk, Khalil. "Analysis of dimensional control in 3D printing." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12146.
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Chen, Cong. "High-Dimensional Generative Models for 3D Perception." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/103948.
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Modern robotics and automation systems require high-level reasoning capability in representing, identifying, and interpreting the three-dimensional data of the real world. Understanding the world's geometric structure by visual data is known as 3D perception. The necessity of analyzing irregular and complex 3D data has led to the development of high-dimensional frameworks for data learning. Here, we design several sparse learning-based approaches for high-dimensional data that effectively tackle multiple perception problems, including data filtering, data recovery, and data retrieval. The frameworks offer generative solutions for analyzing complex and irregular data structures without prior knowledge of data.
The first part of the dissertation proposes a novel method that simultaneously filters point cloud noise and outliers as well as completing missing data by utilizing a unified framework consisting of a novel tensor data representation, an adaptive feature encoder, and a generative Bayesian network. In the next section, a novel multi-level generative chaotic Recurrent Neural Network (RNN) has been proposed using a sparse tensor structure for image restoration. In the last part of the dissertation, we discuss the detection followed by localization, where we discuss extracting features from sparse tensors for data retrieval.Doctor of Philosophy
The development of automation systems and robotics brought the modern world unrivaled affluence and convenience. However, the current automated tasks are mainly simple repetitive motions. Tasks that require more artificial capability with advanced visual cognition are still an unsolved problem for automation. Many of the high-level cognition-based tasks require the accurate visual perception of the environment and dynamic objects from the data received from the optical sensor. The capability to represent, identify and interpret complex visual data for understanding the geometric structure of the world is 3D perception. To better tackle the existing 3D perception challenges, this dissertation proposed a set of generative learning-based frameworks on sparse tensor data for various high-dimensional robotics perception applications: underwater point cloud filtering, image restoration, deformation detection, and localization. Underwater point cloud data is relevant for many applications such as environmental monitoring or geological exploration. The data collected with sonar sensors are however subjected to different types of noise, including holes, noise measurements, and outliers. In the first chapter, we propose a generative model for point cloud data recovery using Variational Bayesian (VB) based sparse tensor factorization methods to tackle these three defects simultaneously. In the second part of the dissertation, we propose an image restoration technique to tackle missing data, which is essential for many perception applications. An efficient generative chaotic RNN framework has been introduced for recovering the sparse tensor from a single corrupted image for various types of missing data. In the last chapter, a multi-level CNN for high-dimension tensor feature extraction for underwater vehicle localization has been proposed.
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Barillot, Christian. "Fusion de données et imagerie 3D en médecine." [S.l.] : [s.n.], 1999. ftp://ftp.irisa.fr/techreports/habilitations/barillot.pdf.
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Poulsen, Carsten. "Development of a positioning system for 3D ultrasound." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-101805-180813/.
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Hutton, Claude O. "3D battlespace visualization using operational planning data." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2003. http://library.nps.navy.mil/uhtbin/hyperion-image/03sep%5FHutton.pdf.
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Thesis (M.S. in Computer Science)--Naval Postgraduate School, September 2003.Thesis advisor(s): Don Brutzman, Curtis Blais. Includes bibliographical references (p. 103-104). Also available online.
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Li, Yan, and 李燕. "3D reconstruction and camera calibration from circular." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://ndltd.ncl.edu.tw/handle/41449873847192900368.
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Pourbakhsh, Seyed Alireza. "Dummy TSV-Based Timing Optimization for 3D On-Chip Memory." Thesis, North Dakota State University, 2016. https://hdl.handle.net/10365/29093.
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Design and fabrication of three-dimensional (3D) ICs is one the newest and hottest trends in semiconductor manufacturing industry. In 3D ICs, multiple 2D silicon dies are stacked vertically, and through silicon vias (TSVs) are used to transfer power and signals between different dies. The electrical characteristic of TSVs can be modeled with equivalent circuits consisted of passive elements. In this thesis, we use “dummy” TSVs as electrical delay units in 3D SRAMs. Our results prove that dummy TSVs based delay units are as effective as conventional delay cells in performance, increase the operational frequency of SRAM up to 110%, reduce the usage of silicon area up to 88%, induce negligible power overhead, and improve robustness against voltage supply variation and fluctuation.