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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Contribution à l'extraction et à l'exploitation d'attributs géométriques du maillage 3D de fragments archéologiques

Laugerotte, Cédric 03 March 2006 (has links)
Ce document porte sur l'extraction d'attributs géométriques présents sur les modèles 3D résultant de l'acquisition numérique de fragments archéologiques. Ces attributs sont ensuite exploités à des fins de classifications, de reconstructions et de remontages.
2

Vers un système d'assistance à l'interaction 3D pour le travail et le télétravail collaboratif dans les environnements de réalité virtuelle et augmentée / Towards an assistance system for 3D interaction dedicated to work and collaborative telework in virtual and augmented reality environments

Ouramdane, Nassima 25 November 2008 (has links)
La réalité virtuelle est une discipline qui se situe à la croisée de plusieurs domaines tels que l’infographie, la simulation, la téléopération, le travail collaboratif, etc. L'interaction 3D est la composante motrice de la réalité virtuelle. Elle permet à l'utilisateur d'interagir avec les entités de l'environnement virtuel. Il existe différentes techniques d'interaction 3D qui sont dédiées aux différentes tâches d’interaction 3D à savoir la navigation, la sélection, la manipulation et le contrôle d’application. En général, la technique utilisée cherche à accomplir une tâche d'interaction 3D sans prendre en considération les exigences des environnements dédies pour la téléopération et les environnements collaboratifs. Les tâches de téléopération doivent respecter un certain nombre de contraintes, qui sont : des sélections et des manipulations sécurisées et précises. Les environnements collaboratifs sont des mondes dans lesquels les utilisateurs interagissent ensemble pour réaliser des tâches communes. La complexité de ces environnements est liée à l'interaction d'un groupe d'utilisateurs avec des entités partagées. L’objectif de ce travail est de modéliser, de concevoir, d’implémenter et d’évaluer un système d’assistance à l’interaction 3D mono-utilisateur et multi-utilisateurs. Notre concept est centré sur l’utilisateur et ses intérêts dans le monde virtuel, il est basé sur le principe d’anticipation du geste de l’utilisateur par l’assistance de ce dernier. Notre système d’assistance peut être considéré comme un moyen de contourner les limitations de certaines techniques d’interaction 3D classiques afin de les rendre utilisables dans des contextes différents. / Virtual Reality is a research domain that is situated at the crossing of several domains as infography, simulation, teleoperation, collaborative work, etc. The 3D interaction is a core component of virtual reality. It allows the user to interact with the entities of the virtual environment. There exists different 3D interaction techniques that are dedicated to the different tasks of 3D interaction that are navigation, selection, manipulation and command control. In most cases, the 3D interaction techniques are only used to perform one of the 3D interaction tasks without taking into account the requirements of complex environments such as teleoperation environments and collaborative environments. Teleoperation tasks are complex tasks and must fulfill some constraints that are : very precise seizures of objects and secure selections and manipulations. The collaborative environments are worlds in which users interact between them to accomplish goals together. The complexity of these environments is related to the interaction of a group of users with shared entities. The aim of this work is to model, conceive, implement and evaluate our 3D interaction assistance system for mono and multi users. Our study is centred on the user and its interests in the virtual world. The concept of this study is based on the principle of anticipation of the user’s gesture by the assistance him. Our 3D interaction assistance system is considered as a mean to bypass the limitations of some 3D interaction classical techniques in order to make them usable in different contexts.
3

L'interaction 3D adaptative : une approche basée sur les méthodes de traitement de données multi-capteurs / Adaptive 3D interaction : an approach based on multi-sensor data processing

Boudoin, Pierre 06 October 2010 (has links)
La réalité virtuelle est un domaine touchant à plusieurs disciplines. Par le biais de l’interaction 3D l’Homme peut accomplir des tâches dans un environnement virtuel en utilisant des techniques d’interaction 3D. Ces techniques sont souvent mono-tâches et s’appuient sur l’utilisation de matériel de réalité virtuelle bien spécifique. Le passage d’une tâche de l’interaction 3D à une autre est le plus souvent à la charge de l’utilisateur,ou bien du programmeur. Cependant de nombreux problèmes sont présents dans ces systèmes, dits de réalité virtuelle. En effet, des problèmes matériels le plus souvent dû aux technologies utilisées sont présents et peuvent induire un comportement erratique du système. De plus, il peut arriver que les techniques d’interaction 3D ne soient pas adaptées à l’application de réalité virtuelle, ou que celles-ci soient trop complexes à utiliser pour le novice. Tous ces problèmes nuisent à l’immersion de l’être humain dans l’environnement virtuel ainsi qu’aux performances de l’interaction 3D et donc à l’accomplissement de la tâche dans l’application de réalité virtuelle.L’objectif de ce travail est de proposer un système d’interaction 3D adaptative. Par interaction3D adaptative, on cherche à définir une interaction 3D qui soit continue tant au niveau des données qu’au basculement d’une tâche à l’autre. Nous avons donc modélisé et conçu un ensemble de composants pour accomplir cet objectif. Nous avons modélisé une technique d’interaction 3D pouvant être utilisé de manière continue même lors du basculement d’une tâche. Nous avons également conçu un système qui permet d’automatiser le basculement d’une tâche de l’interaction 3D vers une autre en estimant la tâche que souhaite accomplir l’utilisateur. Enfin, un dernier composant a pour rôle d’améliorer la précision et de garantir la continuité du tracking. / Virtual reality is a field involving multiple disciplines. Through the 3D interaction ofwe can perform tasks in a virtual environment using 3D interaction techniques. These techniques are often mono-task and are based on the use of specific virtual reality devices.The transition from a 3D interaction task to another is usually to the responsibility ofthe user, or programmer. Indeed, due to the technologies used, hardware problems are present and can induce erratic behaviors from the system. Moreover, it may happen that 3D interaction techniques are not suited to the application of virtual reality, or that they are too complex to use for the novice. All these problems affect the immersion of the user in the virtual environment and the performance of 3D interaction and thus, to accomplish the task in virtual reality application.The aim of this work is to propose an adaptive 3D interaction system. Adaptive 3Dinteraction, defines a 3D interaction thas is continuous in terms of data and switching from one task to another. So we have modeled and designed a set of components to accomplish this goal. We designed a 3D interaction technique which, can be used continuously even when switching to a task. We have also designed a system that automates the switch from a 3D interaction task to another task by estimating the task that the userwants to accomplish. The last component’s role is to improve accuracy and ensure thecontinuity of tracking data.
4

Interaction en réalité mixte appliquée à l'archéologie sous-marine / Interaction in mixed reality applied to underwater archeology

Haydar, Mahmoud 08 December 2011 (has links)
L’intérêt porté par l’archéologie à la réalité virtuelle est croissant. La réalité virtuelle est devenue un outil nécessaire pour l’exploration et l’étude des sites archéologiques, et plus particulièrement, les sites archéologiques sous-marins qui se révèlent parfois difficile d’accès. Les études actuelles proposent des solutions en réalité virtuelle ou en réalité augmentée sous forme d’environnements virtuels avec une interaction virtuelle et/ou augmentée mais aucune étude n’a vraiment essayé de comparer ces deux aspects de l’interaction. Nous présentons dans ce mémoire trois environnements en réalité virtuelle et un environnement en réalité augmentée où nous proposons des nouvelles méthodes d’interaction. Ainsi, nous évaluons leurs fonctionnalités d’un point de vue archéologique, nous étudions l’influence du niveau d’immersion sur les performances de l’interaction et nous réalisons une comparaison entre l’interaction en réalité virtuelle et en réalité augmentée. / The interest in archeology virtual reality is growing. Virtual reality has become a necessary tool for exploration and study of archaeological sites, and more specifically, the underwater archaeological sites that sometimes prove difficult to access. Current studies suggest solutions in virtual reality or augmented reality in the form of virtual environments with virtual interaction and/or augmented interaction but no studies have really tried to compare these two aspects of interaction. We present in this thesis three environments in virtual reality and an environment in augmented reality when we propose new methods of interaction. Thus, we evaluate their archaeological functionality, we study the influence of level of immersion on performance of the interaction and we make a comparison between interaction in virtual reality and interaction in augmented reality.
5

3D surface matching from range images using multiscale local features.

Ho, Huy Tho January 2009 (has links)
Object recognition is one of the most important problems in computer vision. Traditional object recognition techniques are usually performed on optical images that are 2D projections of the 3D world. Information about the depth of objects in the scene is not provided explicitly in these images and thus, it makes 2D object recognition techniques sensitive to changes in illumination and shadowing. As surface acquisition methods such as LADAR or range scanners are becoming more popular, there is an increasing interest in the use of three-dimensional geometric data in object recognition to overcome these limitations. However, the matching of 3D free-form surfaces is also a difficult problem due to the shape and topological complexity of 3D surfaces. In addition, the problem is further complicated by other issues such as variations in surface sampling resolution, occlusion, clutter and sensor noise. The huge amount of information required to describe a 3D surface is also another challenge that 3D surface matching techniques have to deal with. This thesis investigates the problems of 3D surface matching that include 3D surface registration and object recognition from range images. It focuses on developing a novel and efficient framework for aligning 3D surfaces in different coordinate systems and from this, recognizing 3D models from scenes with high levels of occlusion and clutter using multi-scale local features. The first part of the thesis presents two different schemes for extracting salient geometric features from 3D surfaces using surface curvature measures known as the curvedness and shape index. By deriving the scale-space representation of the input surface, surface positions with high local curvature or high local shape variations are selected as features at various degrees of scale. One advantage of the proposed approaches is their applicability to both 3D meshes with connectivity information and unstructured point clouds. In the second part of the thesis, an application of the multi-scale feature extraction framework to 3D surface registration and object recognition is proposed. A Delaunay tetrahedrization is performed on the features extracted from each input range image to obtain a set of triangles. Possible correspondences are found by matching all possible pairs of triangles between the scene and model surfaces. From these correspondences, possible transformations between the two surfaces can be hypothesized and tested. In order to increase the accuracy and efficiency of the algorithm, various surface geometric and rigidity constraints are applied to prune unlikely correspondences. By finding the match that aligns the largest number of features between the two surfaces, the best transformation can be estimated. In the case of surface registration, this transformation can be used to coarse-align two different views of the same object. In the case of 3D object recognition, it provides information about the possible pose (location and orientation) of the model in the scene surface. Experimental results on a variety of 3D models and real scenes are shown to verify the effectiveness and robustness of the approach. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1474505 / Thesis (M.App.Sc.) -- University of Adelaide, School of Electrical and Electronic Engineering, 2009
6

Stereoskopisk 3D-film : En studie om tittarens upplevelse av 3D-film

Edlund, Magnus, Lindahl, Robin January 2014 (has links)
Since the release of Avatar in 2009, the 3D movie industry has experienced an apparent growth. Almost all blockbuster movies are being released in 3D at the cinema, but the 3D format has been met with mixed opinions by the consumers. Some argue that 3D is the future, while others believe that the 2D format is enough for an appreciated movie experience. Through a qualitative survey, twenty participants with 3DTV in their homes answered questions regarding their experience of 3D movies and what improvements they desire. We suggest that 3D film creates immersion, realism and effects that 2D films can´t handle. We also show that 3D, even though it has become a standard in today's television sets, is seen as an unnecessary technology, and has several problem areas that need attention in order to give a better experience.
7

Procedimentos de análise em magnetometria: estimativa de magnetização remanente visando inversões para exploração mineral / Analysis Procedures in Magnetics: Estimative of Remanent Magnetization Aiming for Inversions for Mineral Exploration

Louro, Vinicius Hector Abud 06 March 2013 (has links)
Neste estudo é apresentado um procedimento de análise de dados magnéticos em casos de presença de magnetização remanente para, ao final do processo, a realização de uma inversão mais rápida e fiel ao comportamento do alvo em sub-superfície. O procedimento é composto por seis passos: (1) Delimitação lateral do alvo; (2) Estimativa de suas profundidades; (3) Estimativa das direções de inclinação e declinação aparentes de seu vetor de magnetização total; (4) Modelagem inicial com inferência de valores de susceptibilidades oriundos de estudos geológicos anteriores sobre o alvo e/ou sua região; (5) Inversão dos dados magnéticos utilizando o modelo inicial; e (6) atribuição das características magnéticas do passo (3) sobre o modelo de contraste de susceptibilidade magnética obtido com a inversão para a modelagem final do alvo, conhecendo-se seus vetores de magnetização induzida, total e, por subtração vetorial de ambos, remanente. Este procedimento foi aplicado a 108 casos sintéticos e a 8 casos reais pertencentes às províncias ígneas do Alto do Paranaíba e Rondoniana-San-Ignácio. Os resultados do uso deste procedimento indicaram uma recuperação das direções das componentes de magnetização com erro menor que 10%, em casos sintéticos, uma redução de mais de 20% no tempo de inversão com o uso de modelos iniciais, e qualitativamente, apresentaram modelos mais próximos dos originais (nos casos sintéticos) e geologicamente factíveis nos casos reais. / In this study, we present a procedure of analysis of magnetic data when remanence is present in order to, at the end of the process, obtain an inversion faster and more reliable inversion. The procedure is composed of six steps: (1) Estimation of the borders of the target; (2) Estimation of its depths; (3) A sweeping for the total apparent inclination and declination directions; (4) Initial modeling of a synthetic body, based on the recovered geometry and depth, on the directions of inclination and declination of the total magnetic field, and on previous analysis of the target and/or its region; (5) Inversion of magnetic data using the initial model; and (6) Attribution of the magnetic features of step (3) to the model recovered by the inversion for a final modeling of the target, estimating as well its remanent magnetization; the last through the vectorial resultant of the induction and total magnetization subtraction. This procedure was applied to 108 synthetic and to 8 real cases from the Alto do Paranaíba and Rondonian-San Ignacio Igneous Provinces. Their results pointed out that the error between the recovered directions of the magnetization components and the original values, in synthetic cases, was smaller than 10%; The inversions had their processing-time reduced in more than 20% and, qualitatively, presented models were more similar to the original (synthetic cases) and geologically feasible (real cases).
8

Interaction 3D collaborative en réalité virtuelle / Collaborative 3D interaction in virual reality

Domingues, Christophe 13 October 2010 (has links)
Les Environnements Virtuels Collaboratifs (EVCs) sont des environnements virtuels peuplés où les utilisateurs interagissent entre eux pour réaliser des actions communes (déplacement en groupe, sélection et manipulation d’objets en commun, communication, etc.). Dans les EVCs, la complexité se situe au niveau de l’interaction d’un groupe d’utilisateurs avec les objets. En effet, il y a plusieurs contraintes à respecter notamment celles liées à la coordination des actions des différents utilisateurs et la conscience de présence d’un utilisateur par rapport aux objets de l’environnement et par rapport aux autres utilisateurs. Notre travail de recherche s’inscrit dans le cadre de l’interaction 3D et de la collaboration en Réalité Virtuelle. Il développe la notion d’assistance à l’interaction 3D collaborative et à son évaluation. Pour l’assistance à l’interaction 3D collaborative, une approche basée sur un Workflow intégrant l’anticipation et la gestion des interactions du groupe est proposée. Pour l’assistance à l’évaluation des techniques d’interaction 3D, une approche basée sur les méthodes empiriques d’évaluation intégrant les outils statistiques de recherche d’informations est proposée. L’objectif de cette thèse est de modéliser, concevoir, implémenter et évaluer un système d’assistance à l’interaction 3D collaborative. / Collaborative Virtual Environments (CVE) are virtual environments populated where users interact to perform common actions (moving in groups, and selection manipulating objects, communication, etc..). In CVE, the complexity is focused to the interaction of a group of users with objects. Indeed, there are several constraints to take into account as coordination of users’ action and the sensé of the presence between users and objects and between users. Our research is part of 3D interaction and Collaboration in Virtual Reality. We developed the concept of Assistance to Collaborative 3D interaction and evaluation. ToAssist Collaborative 3D interaction, an approach based on a Workflow integrating the anticipation and management of interactions group is proposed. For the assistance of the evaluation, an approach based on empirical methods is proposed which used data mining Tools. The objective of this thesis is to model, design, implement and evaluate a system to support interaction 3D Collaborative.
9

Förslag till 3D-strategi för Skövde kommun / Proposal for a 3D strategy for Skövde municipality

Karlsson, Lars January 2008 (has links)
<p>Att vilja lagra sina geografiska data i tre dimensioner har börjat bli allt vanligare bland de svenska kommunerna. Man vill utifrån dessa data skapa en 3D-modell över sina tätorter med realistiska byggnader och andra objekt. Detta ger ökade möjligheter inom planprocesser, bygglov, skuggstudier och andra kommunala ändamål för invånarna.Detta examensarbete hade till syfte att ta fram ett förslag till 3D-strategi för Skövde kommun. De har idag sina data lagrade i två dimensioner i en Oracle-databas och man har en del andra material som till exempel punktmoln från laserskanning som skulle kunna användas för att skapa en geografisk databas i tre dimensioner.Examensarbetet tar upp olika mjukvaror man kan använda för skapandet och användandet av 3D-modeller. Den tar även upp vilka standarder man kan använda för att lagra geografiska data i tre dimensioner och vilka databaser man kan använda för detta ändamål. Dessutom berörs hur man skulle kunna ajourföra data och hur långt några andra kommuner har kommit i deras arbete med en 3D-strategi.Som slutsats så ser man att det det är svårt att hitta information inom området. Men att det finns mycket information att hämta från andra kommuner som redan gjort en hel del arbete. Ett bra exempel är Göteborg som tagit fram en riktigt fin modell som man kan se som en förebild. Man kan också se att Oracle och CityGML är en bra lösning för lagring av data i 3D. Det finns också företag som tagit fram lösningar för skapandet av kompletta 3D-lösningar efter en automatisk process men att de kan behöva utvecklas mer för att användas i dessa ändamål.</p> / <p>Swedish municipalities increasingly want to store their spatial data in three dimensions. On the basis of these data they want to create a 3D model of their cities with realistic buildings and other items. This provides increased opportunities in planning, building applications, studies of shadows and other municipal purposes for the residents.The purpose of this degree project was to develop a proposal for a 3D strategy for Skövde municipality. For the moment they have their data stored in two dimensions in an Oracle database and they have a number of other materials such as point clouds from laser scanning that could be used to create a spatial database in three dimensions.The degree project points to various software that can be used for the creation and use of 3D models. It also shows standards that can be used for storing of spatial data in three dimensions and which databases can be used for this purpose. Furthermore the study deals with how the model can be updated and how far other municipalities have advanced in their work with 3D strategies.As a conclusion, we can notice that it is difficult to find information in this area. But there are a lot of information to require from other municipalities that already has done a lot of work. A great example is Göteborg who have created a really nice model that can be seen as a paragon. You can also see that Oracle and CityGML is a good solution for storage of data in 3D. There are also companies that have developed solutions for the creation of complete 3D solutions trough an automatic process but that they need to develop it more for making it able to use for this purposes.</p>
10

Förslag till 3D-strategi för Skövde kommun / Proposal for a 3D strategy for Skövde municipality

Karlsson, Lars January 2008 (has links)
Att vilja lagra sina geografiska data i tre dimensioner har börjat bli allt vanligare bland de svenska kommunerna. Man vill utifrån dessa data skapa en 3D-modell över sina tätorter med realistiska byggnader och andra objekt. Detta ger ökade möjligheter inom planprocesser, bygglov, skuggstudier och andra kommunala ändamål för invånarna.Detta examensarbete hade till syfte att ta fram ett förslag till 3D-strategi för Skövde kommun. De har idag sina data lagrade i två dimensioner i en Oracle-databas och man har en del andra material som till exempel punktmoln från laserskanning som skulle kunna användas för att skapa en geografisk databas i tre dimensioner.Examensarbetet tar upp olika mjukvaror man kan använda för skapandet och användandet av 3D-modeller. Den tar även upp vilka standarder man kan använda för att lagra geografiska data i tre dimensioner och vilka databaser man kan använda för detta ändamål. Dessutom berörs hur man skulle kunna ajourföra data och hur långt några andra kommuner har kommit i deras arbete med en 3D-strategi.Som slutsats så ser man att det det är svårt att hitta information inom området. Men att det finns mycket information att hämta från andra kommuner som redan gjort en hel del arbete. Ett bra exempel är Göteborg som tagit fram en riktigt fin modell som man kan se som en förebild. Man kan också se att Oracle och CityGML är en bra lösning för lagring av data i 3D. Det finns också företag som tagit fram lösningar för skapandet av kompletta 3D-lösningar efter en automatisk process men att de kan behöva utvecklas mer för att användas i dessa ändamål. / Swedish municipalities increasingly want to store their spatial data in three dimensions. On the basis of these data they want to create a 3D model of their cities with realistic buildings and other items. This provides increased opportunities in planning, building applications, studies of shadows and other municipal purposes for the residents.The purpose of this degree project was to develop a proposal for a 3D strategy for Skövde municipality. For the moment they have their data stored in two dimensions in an Oracle database and they have a number of other materials such as point clouds from laser scanning that could be used to create a spatial database in three dimensions.The degree project points to various software that can be used for the creation and use of 3D models. It also shows standards that can be used for storing of spatial data in three dimensions and which databases can be used for this purpose. Furthermore the study deals with how the model can be updated and how far other municipalities have advanced in their work with 3D strategies.As a conclusion, we can notice that it is difficult to find information in this area. But there are a lot of information to require from other municipalities that already has done a lot of work. A great example is Göteborg who have created a really nice model that can be seen as a paragon. You can also see that Oracle and CityGML is a good solution for storage of data in 3D. There are also companies that have developed solutions for the creation of complete 3D solutions trough an automatic process but that they need to develop it more for making it able to use for this purposes.

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