Dissertations / Theses on the topic '3D visualisations'
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Sarton, Jonathan. "Visualisations interactives haute-performance de données volumiques massives : une approche out-of-core multi-résolution basée GPUs." Thesis, Reims, 2018. http://www.theses.fr/2018REIMS022/document.
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Les travaux de cette thèse s'inscrivent dans le cadre du projet PIA2 3DNeuroSecure. Ce dernier vise à proposer un système collaboratif de navigation multi-échelle interactive dans des données visuelles massives (Visual Big Data) ayant pour cadre applicatif l'imagerie biomédicale 3D ultra-haute résolution (ordre du micron) possiblement multi-modale. En outre, ce système devra être capable d'intégrer divers traitements et/ou annotations (tags) au travers de ressources HPC distantes. Toutes ces opérations doivent être envisagées sans possibilité de stockage complet en mémoire (techniques out-of-core : structures pyramidales, tuilées, … avec ou sans compression …). La volumétrie des données images envisagées (Visual Big Data) induit par ailleurs le découplage des lieux de capture/imagerie/génération (histologie, confocal, imageurs médicaux variés, simulation …), de ceux de stockage et calcul haute performance (data center) mais aussi de ceux de manipulation des données acquises (divers périphériques connectés, mobiles ou non, tablette, PC, mur d’images, salle de RV …). La visualisation restituée en streaming à l’usager sera adaptée à son périphérique, tant en termes de résolution (Full HD à GigaPixel) que de rendu 3D (« à plat » classique, en relief stéréoscopique à lunettes, en relief autostéréoscopique sans lunettes). L'ensemble de ces développements pris en charge par le CReSTIC avec l'appui de la MaSCA (Maison de la Simulation de Champagne-Ardenne) se résument donc par : - la définition et la mise en oeuvre des structures de données adaptées à la visualisation out-of-core des visual big data (VBD) ciblées - l’adaptation des traitements spécifiques des partenaires comme des rendus 3D interactifs à ces nouvelles structures de données - les choix techniques d’architecture pour le HPC et la virtualisation de l’application de navigation pour profiter au mieux des ressources du datacanter local ROMEO. Le rendu relief avec ou sans lunettes, avec ou sans compression du flux vidéo relief associé seront opérés au niveau du logiciel MINT de l’URCA qui servira de support de développementThese thesis studies are part of the PIA2 project 3DNeuroSecure. This one aims to provide a collaborative system of interactive multi-scale navigation within visual big data (VDB) with ultra-high definition (tera-voxels), potentially multimodal, 3D biomedical imaging as application framework. In addition, this system will be able to integrate a variety of processing and/or annotations (tags) through remote HPC resources. All of these treatments must be possible in an out-of-core context. Because of the visual big data, we have to decoupled the location of acquisition from ones of storage and high performance computation and from ones for the manipulation of the data (various connected devices, mobile or not, smartphone, PC, large display wall, virtual reality room ...). The streaming visualization will be adapted to the user device in terms of both resolution (Full HD to GigaPixel) and 3D rendering (classic rendering on 2D screens, stereoscopic with glasses or autostereoscopic without glasses). All these developments supported by the CReSTIC with the support of MaSCA (Maison de la Simulation de Champagne-Ardenne) can therefore be summarized as: - the definition and implementation of the data structures adapted to the out-of-core visualization of the targeted visual big data. - the adaptation of the specific treatments partners, like interactive 3D rendering, to these new data structures. - the technical architecture choices for the HPC and the virtualization of the navigation software application, to take advantage of "ROMEO", the local datacenter. The auto-/stereoscopic rendering with or without glasses will be operated within the MINT software of the "université de Reims Champagne-Ardenne"
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Brunner, Thalia. "Suspension of disbelief: Animating believable 3D nebula visual effects utilising real-time technology." Thesis, Queensland University of Technology, 2021. https://eprints.qut.edu.au/213208/1/Thalia_Brunner_Thesis.pdf.
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This practice-based research aimed to investigate and identify the key aesthetic and technical considerations for the creation of believable, real-time 3D nebula VFX as an individual animation practitioner. Real-time technology was utilised as an advancement of traditional VFX practices, improving the quality of outcomes through more creative control, faster render times and less reliance on computing power. Three cycles of creative practice were undertaken, resulting in three, 3D visualisations of nebula.
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Dare, Fadeke Taiye. "A novel methodology for e-learning space design in HEI campuses." Thesis, University of Wolverhampton, 2011. http://hdl.handle.net/2436/209931.
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The Higher Education Institution and the Construction Industry are yet to define the most appropriate and effective design parameters for E-learning spaces. Those which exist, focus mainly on cost, budget and timely delivery i.e. the process only not the product. An effective approach to E-learning space design is needed to address the problems of space efficiency, effectiveness, quality, innovativeness, performance and client satisfaction. This study aimed to develop a novel methodology for e-learning space design, by investigating: the impact of e-learning on facilities and design; the impact of e-learning on the design of future spaces; the impact of blended learning on space design; designing for the learn anytime, anywhere paradigm; security issues of e-learning and e-learning space design, the levels of design risk in an e-learning infrastructure and inclusive design issues. A Grounded theory approach was used during initial desk studies, synchronized with a three part forum and pilot survey of 33participants. From this process, two hypotheses emerged; firstly, e-learning space design could affect users‘ learning outcomes and secondly that; user‘s learning requirements were different and varied. To investigate further, site based analyses of 11 HEI‘s, 10 interviews and subsequently a questionnaire survey was administered. Users‘ and stakeholders requirements and good examples of e-learning space design were identified. Data were analysed using a mixed-method research design approach. Three main constructs, Space design, Technology and the E-learning Space Design research focus (ELSD focus), emerged as significant components in the development of a novel framework for the design of e-learning spaces. The relationship between the components is such that the design of spaces with consideration of the ELSD research focus would ensure the effective identification, interpretation and delivery of users‘ requirement while maximising the benefits of the adoption of appropriate technology within HEI facilities. This was therefore proposed as the realistic framework/model for future design of E- learning Spaces in HEI campuses. The framework was adapted into a conceptual design guide to provide guidance for future space design. It is expected the study will support the HEI sector globally as it moves towards achieving best practice solutions to future E-learning space design in HEI campuses.
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Maselino, Prince. "Load balancing for parallel 3D visualisation." Thesis, University of Westminster, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.442101.
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Boyle, John. "Using 3D graphics for database visualisation." Thesis, University of Aberdeen, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307951.
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The upsurge in the number of casual users and the general acceptance of computer technology has shown that the principal driving force in software engineering is shifting from functionality to usability. It has also become evident that the desktop metaphor and its whole related genre do not provide the modern interface designer with the expressive power that is needed. Nowhere is a new approach more needed than in interfaces for databases. Previous studies in interface design for database management systems have attempted to use solely the desktop metaphor. We have used three dimensional graphical techniques to construct an interface, called Amaze for our object oriented database P/FDM. Interactive animated 3D graphics have been embedded inside a standard menu driven framework. Using 3D graphics new metaphors have been developed to aid the user interaction. Our development has taken a modular approach, which allowed us to develop a number of different visualisations for query construction, the structure of the database and result representation. It is possible to view the data using a number of multimodal displays (a number of customised multimodal displays have been built). Amaze has been used on a variety of different data sets (including a protein structure database, a personnel database and an antibody database). These databases differ greatly in size and complexity of their semantics. The work discussed in this thesis suggests an alternative approach to user interface design for database systems, it introduces the idea of Database Visualisation and suggests novel mechanisms for computer interaction using 3D graphics.
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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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Mao, Bo. "Visualisation and Generalisation of 3D City Models." Licentiate thesis, KTH, Geoinformatics, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-24345.
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3D city models have been widely used in different applications such as urban planning, traffic control, disaster management etc. Effective visualisation of 3D city models in various scales is one of the pivotal techniques to implement these applications. In this thesis, a framework is proposed to visualise the 3D city models both online and offline using City Geography Makeup Language (CityGML) and Extensible 3D (X3D) to represent and present the models. Then, generalisation methods are studied and tailored to create 3D city scenes in multi-scale dynamically. Finally, the quality of generalised 3D city models is evaluated by measuring the visual similarity from the original models.
In the proposed visualisation framework, 3D city models are stored in CityGML format which supports both geometric and semantic information. These CityGML files are parsed to create 3D scenes and be visualised with existing 3D standard. Because the input and output in the framework are all standardised, it is possible to integrate city models from different sources and visualise them through the different viewers.
Considering the complexity of the city objects, generalisation methods are studied to simplify the city models and increase the visualisation efficiency. In this thesis, the aggregation and typification methods are improved to simplify the 3D city models.
Multiple representation data structures are required to store the generalisation information for dynamic visualisation. One of these is the CityTree, a novel structure to represent building group, which is tested for building aggregation. Meanwhile, Minimum Spanning Tree (MST) is employed to detect the linear building group structures in the city models and they are typified with different strategies. According to the experiments results, by using the CityTree, the generalised 3D city model creation time is reduced by more than 50%.
Different generalisation strategies lead to different outcomes. It is important to evaluate the quality of the generalised models. In this thesis a new evaluation method is proposed: visual features of the 3D city models are represented by Attributed Relation Graph (ARG) and their similarity distances are calculated with Nested Earth Mover’s Distance (NEMD) algorithm. The calculation results and user survey show that the ARG and NEMD methods can reflect the visual similarity between generalised city models and the original ones.
QC 20100923
ViSuCity Project
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Tang, Hui. "Méthodologies de visualisation 3D en imagerie médicale." Phd thesis, Université Rennes 1, 2008. http://tel.archives-ouvertes.fr/tel-00355629.
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Ce mémoire de Thèse se focalise sur certains des problèmes non résolus en visualisation scientifique. Plus particulièrement nous avons pris une problématique médicale bien spécifique, la chirurgie conservatrice des tumeurs rénales, comme cadre applicatif pour l'élaboration de nouvelles solutions incluant des techniques de recalage de données, de segmentation et de visualisation 3D.L'uroscan fournit 3 à 4 volumes présentant une information complémentaire sur l'anatomie rénale. La première étape consiste à mettre en correspondance ces différents volumes par une technique de recalage rigide du volume rénal basée sur la maximisation locale de l'information mutuelle.
L'idée principale de ce mémoire de Thèse est de proposer une visualisation de l'anatomie rénale directement à partir de ces données fusionnées. Pour cela, une technique de classification statistique des données basée sur une modélisation de la distribution des valeurs par un mélange de Gaussiennes incluant une information spatiale a été développée. Différentes techniques de visualisation 3D ont ensuite été adaptées à la représentation de cette information et comparées entre-elles.
Les techniques de représentation de surfaces peuvent être accélérées par des procédures de simplifications de maillages. Dans ce cadre, nous avons proposé deux métriques de description de la surface basées sur les moments géométriques et pouvant être incluses dans une telle procédure.
Ces différentes solutions, même si elles ont été développées dans le cadre de la représentation des structures anatomiques rénale, sont suffisamment génériques pour être utilisées ou adaptées à d'autres organes ou à d'autres applications médicales.
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Mao, Bo. "Visualisation and Generalisation of 3D City Models." Doctoral thesis, KTH, Geoinformatik och Geodesi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48174.
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3D city models have been widely used in various applications such as urban planning, traffic control, disaster management etc. Efficient visualisation of 3D city models in different levels of detail (LODs) is one of the pivotal technologies to support these applications. In this thesis, a framework is proposed to visualise the 3D city models online. Then, generalisation methods are studied and tailored to create 3D city scenes in different scales dynamically. Multiple representation structures are designed to preserve the generalisation results on different level. Finally, the quality of the generalised 3D city models is evaluated by measuring the visual similarity with the original models. In the proposed online visualisation framework, City Geography Makeup Language (CityGML) is used to represent city models, then 3D scenes in Extensible 3D (X3D) are generated from the CityGML data and dynamically updated to the user side for visualisation in the Web-based Graphics Library (WebGL) supported browsers with X3D Document Object Model (X3DOM) technique. The proposed framework can be implemented at the mainstream browsers without specific plugins, but it can only support online 3D city model visualisation in small area. For visualisation of large data volumes, generalisation methods and multiple representation structures are required. To reduce the 3D data volume, various generalisation methods are investigated to increase the visualisation efficiency. On the city block level, the aggregation and typification methods are improved to simplify the 3D city models. On the street level, buildings are selected according to their visual importance and the results are stored in the indexes for dynamic visualisation. On the building level, a new LOD, shell model, is introduced. It is the exterior shell of LOD3 model, in which the objects such as windows, doors and smaller facilities are projected onto walls. On the facade level, especially for textured 3D buildings, image processing and analysis methods are employed to compress the texture. After the generalisation processes on different levels, multiple representation data structures are required to store the generalised models for dynamic visualisation. On the city block level the CityTree, a novel structure to represent group of buildings, is tested for building aggregation. According to the results, the generalised 3D city model creation time is reduced by more than 50% by using the CityTree. Meanwhile, a Minimum Spanning Tree (MST) is employed to detect the linear building group structures in the city models and they are typified with different strategies. On the building level and the street level, the visible building index is created along the road to support building selection. On facade level the TextureTree, a structure to represent building facade texture, is created based on the texture segmentation. Different generalisation strategies lead to different outcomes. It is critical to evaluate the quality of the generalised models. Visually salient features of the textured building models such as size, colour, height, etc. are employed to calculate the visual difference between the original and the generalised models. Visual similarity is the criterion in the street view level building selection. In this thesis, the visual similarity is evaluated locally and globally. On the local level, the projection area and the colour difference between the original and the generalised models are considered. On the global level, the visual features of the 3D city models are represented by Attributed Relation Graphs (ARG) and their similarity distances are calculated with the Nested Earth Mover’s Distance (NEMD) algorithm. The overall contribution of this thesis is that 3D city models are generalised in different scales (block, street, building and facade) and the results are stored in multiple representation structures for efficient dynamic visualisation, especially for online visualisation.QC 20111116
ViSuCity
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Green, Damian Alan. "Stratigraphic visualisation for archaeological investigation." Thesis, Brunel University, 2003. http://bura.brunel.ac.uk/handle/2438/2168.
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The principal objective of archaeology is to reconstruct in all possible ways the life of a community at a specific physical location throughout a specific time period. Distinctly separate layers of soil provide evidence for a specific time period. Discovered artefacts are most frequently used to date the layer. An artefact taken out of context is virtually worthless; hence the correct registration of the layer in which they were uncovered is of great importance. The most popular way to record temporal relationships between stratigraphic layers is through the use of the 2D Harris Matrix method. Without accurate 3D spatial recording of the layers, it is difficult if not impossible, to form new stratigraphic correspondences or correlations. New techniques for archaeological recording, reconstruction, visualisation and interpretation in 3D space are described in these works and as a result software has been developed. Within the developed software system, legacy stratigraphy data, reconstructed from archaeological notebooks can be integrated with contemporary photogrammetric models and theodolite point data representations to provide as comprehensive a reconstruction as possible. The new methods developed from this research have the capability to illustrate the progression of the excavation over time. This is made possible after the entry of only two or more strata. Sophisticated, yet easy-to-use tools allow the navigation of the entire site in 3D. Through the use of an animation-bar it is possible to replay through time both the excavation period and the occupation period, that is to say the various time periods in antiquity when human beings occupied these locations. The lack of complete and consistent recording of the soil layers was an issue that proved to be an obstacle for complete reconstruction during the development of these methods. A lack of worldwide archaeological consensus on the methods of stratigraphic recording inhibited development of a universal scientific tool. As a result, new recording methods are suggested to allow more scientific stratigraphic reconstruction.
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Muñoz, Álvaro Aranda. "Comparing 3D interfaces of virtual factories : an iconic 3D interface against an abstract 3D visualisation." Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-4115.
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Context. 3D visualisations are highly demanded in different industries such as virtual factories. However, the benefits that 3D representations can bring to this industry have not been fully explored, being most of the representations either photorealistic or presenting abstract visualisations. Objectives. This thesis explores and compares two prototypes that present a visualisation of the process state of a factory. The first prototype presents a generic interface in which primitive 3D shapes convey the information of the factory status. The second prototype is complemented with specific and iconic 3D models of the factory that help the users associating the conveyed information to the factory flow. The motivation behind this dissertation is that the type of generic interface presented can lead to more reusable interfaces in the future. Methods. For the creation and development of the prototypes, the user-centered design process was followed in which the designs are iterated with users of the factory. Based on the two prototypes, a usability evaluation is conducted to analyse the perceived usability and the usability performance. This is complemented with post-interviews with all the participants. The results are presented attending to the triangulation methodology to support the strength of the qualitative findings. Conclusions. The results show that both interfaces are perceived as highly usable. However, the 3D iconic interface seemed to help the users more in depicting a better mental model of the factory flow, helping the users to complete most of the tasks with faster times.This thesis explores and compares two prototypes that present a visualisation of the process state of a factory. The first prototype presents a generic interface in which primitive 3D shapes convey the information of the factory status. The second prototype is complemented with specific and iconic 3D models of the factory that help the users associating the conveyed information to the factory flow. The motivation behind this dissertation is that the type of generic interface presented can lead to more reusable interfaces in the future.
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Algharabat, Raed S. "Modelling 3D product visualisation for the online retailer." Thesis, Brunel University, 2010. http://bura.brunel.ac.uk/handle/2438/4525.
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This research aims to explain the process that previous researchers have discussed concerning the consumer virtual experience, using three-dimensional (3D) product visualisations, within online retailers. In addition, this research aims to identify the main advantages of using 3D product visualisation in comparison to two-dimensional (2D) static pictures within online retailers. Moreover, using the online Stimulus-Organism-Responses (S-O-R) paradigm, this research aims to model the effect of 3D product visualisation on consumers’ perception and responses towards the online retailer environment. Given that the appearance of the notion of telepresence or presence and their implications on the online retailer, many scholars attempt to build and develop models that can suit these notions online. However, this thesis argues that the notion of 3D telepresence is not the proper terminology to be used within the online retail context and therefore, this research raises the following question “how do consumers perceive 3D product virtualisation (telepresence) compared with 3D product authenticity on online retailers’ websites?” The effects of 3D product visualisation and 2D static pictures have been raised during the past decade to determine which is better for the online consumers. Marketers and information system scholars started wondering about the best device that can generate hedonic and utilitarian values for the consumers. To investigate the main impact of 3D product visualisation and 2D static pictures on hedonic and utilitarian values, this research raises the following questions: How do consumers perceive 3D hedonic values compared with 2D hedonic values on online retailers’ website? How do consumers perceive 3D product visualisation utilitarian values compared with 2D utilitarian values on online retailers’ website? This thesis, based on the previous literature in interactivity and vividness, narrowed down the 3D authenticity antecedents to the control and animated colour constructs. Moreover, to determine the effect of the progressive levels of control and animated colour constructs on the 3D authenticity construct, it raises the following research question: How do different levels of 3D control and animated colours influence 3D authenticity? To determine the effects of the progressive levels of 3D hedonic and utilitarian values on behavioural intention construct, this thesis raises the following research question: How do different levels of 3D hedonic and utilitarian levels influence behavioural intentions? Based on the online S-O-R framework, previous studies investigate the impact of the whole website e-retail environment (many stimuli) on consumers’ responses. Yet, this is the first study that is using one stimulus, namely 3D laptop product visualisation to investigate its impacts on consumers’ perceptions and responses using the online S-OR paradigm. Therefore, this thesis raises the following research question: How do control, animated colours, 3D authenticity, hedonic and utilitarian values affect consumers’ behavioural intention? The results reveal significant differences between 3D telepresence and 3D authenticity constructs. 3D telepresence involves an illusion or a sense of being transported to another place, whereas 3D authenticity refers to the ability to imagine a virtual object as real. The 3D authenticity construct is more significant in simulating an online retailer’s products. The proposed online S-O-R conceptual model achieves acceptable fit and the hypothesised paths are all valid. This research adds to the marketing literature the notion of 3D authenticity and contributes a valid scale to measure that new variable. Moreover, it is the first study that connects and uses the antecedents of 3D authenticity (S), control and animated colours, to investigate their impact on 3D authenticity, hedonic and utilitarian values (O), and the impact of the Organism constructs (O) on behavioural intention (R). Furthermore, the final framework considers the first framework that has studied the impact of one stimulus using the online S-O-R framework on an electronic retailer website environment. Indeed, to the best of the researcher’s knowledge, this is the first study that uses a UK sample to investigate the effects of an authentic 3D product visualisation in an electronic e-retailing industry (i.e., laptops).
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Ottoson, Patrik. "Geographic Indexing and Data Management for 3D-Visualisation." Doctoral thesis, Stockholm : Tekniska högsk, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3235.
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Norberg, Amanda, and Elliot Rask. "3D visualisation of breast reconstruction using Microsoft HoloLens." Thesis, Uppsala universitet, Signaler och System, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-367277.
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The purpose of the project is to create a Mixed Reality (MR) application for the 3D visualisation of the result of a breast reconstruction surgery. The application is to be used before surgery to facilitate communication between patient an surgeon about the expected result. To this purpose Microsoft HoloLens is used, which is a pair of Mixed Reality (MR) glasses developed and manufactured by Microsoft that has a self-contained, holographic rendering computer. For the development of the MR application on the Hololens, MixedRealityToolkit-Unity is used which is a Unity-based toolkit available. The goal of the application is that the user can scan a torso of a patient, render a hologram of the torso and attach to it a prefabricated breast which possibly follows the patient's specification. To prepare a prefabricated breast, a 3D model of the breast is first created in the 3D modelling software Blender. It then gets its texture from a picture taken with the HoloLens camera. The picture is cropped to better fit the model and uploaded as a 2D texture which is then attached to the prefabricated breast, which is imported into Unity. To scan objects, the HoloLens’s operating system feature Surface Observer is used. The resulting mesh from the observer is cropped using a virtual cube, scaled, moved and rotated by the user. The cropped mesh is then smoothed using the Humphrey's Classes smoothing algorithm. To fuse the smoothed mesh with the prefabricated breast model, the Unity components: Colliders and Transforms are used. On a collision the breast's transform parent is set to the mesh’s transform, making the objects transforms behave depending on each other. The MR application has been developed and evaluated. The evaluation results show that the goal has been achieved successfully. The project demonstrates that the Microsoft HoloLens is well suited for developing such medical applications as breast reconstructive surgery visualisations. It can possibly be extended to other surgeries such as showing on a patient’s body how the scar will look after a heart surgery, or a cesarean section.
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Janols, Henrik. "Communicating long-span timber structures with 3D computer visualisation /." Luleå, 2005. http://epubl.luth.se/1402-1757/2005/30.
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Hayat, Khizar. "Visualisation 3D adaptée par insertion synchronisée de données cachées." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2009. http://tel.archives-ouvertes.fr/tel-00400762.
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L'objectif principal de ces travaux de thèse est d'unifier différentes informations 2D et 3D afin de réaliser une visualisation adaptée dans un environnement client/serveur hétérogène en termes de réseau, de traitement et de ressources mémoire. Dans ce contexte, nous avons exploité la nature multi-résolution de la transformée en ondelettes discrètes (TOD) du codeur JPEG2000. L'unification des données est réalisée par insertion aveugle, synchrone ou partiellement synchrone, des données cachées dans le domaine des ondelettes. Une visualisation 3D classique nécessite au moins deux types de données : une image 2D d'intensité, appelé texture, et une forme 3D pouvant être représentée par une image, un modèle 3D ombré ou un maillage de points. Ce type d'image, parfois également appelé carte de profondeur est une image dans laquelle la valeur des pixels reflète la distance du capteur à la surface par imagerie. La texture est une image 2D couleur qui est apposée sur le modèle 3D après triangulation. Au niveau de l'insertion des données cachées, la carte de profondeur est d'abord transformée dans le domaine des ondelettes tandis que la texture est insérée dans le codeur JPEG2000. Le processus de codage JPEG2000 de la texture est interrompue, et les coefficients 3D sont insérés dans la totalité ou dans un sous-ensemble des sous-bandes de la texture. Les données sont re-intégrées dans le codeur standard de JPEG2000 à l'endroit où l'interruption a été faite. Le fichier résultant peut alors être envoyé à travers tous types de canal de communication comme un autre fichier standard issu du codeur JPEG2000. Les différents niveaux de résolution et le caractère synchronisé de nos algorithmes permettent une visualisation en 3D, même avec peu de sous-bandes de résolution suite à un transfert partiel ou retardé. La méthode permet ainsi d'effectuer une visualisation à partir uniquement d'une fraction des données. Dans ce cas nous remplaçons par des zéros les coefficients des sous-bandes manquantes. La première phase de ce travail a concerné l'imperceptibilité; c'est la raison pour laquelle l'insertion a été réalisée dans les bits de poids plus faibles. La deuxième phase de ces travaux a concerné la robustesse, c'est pourquoi une stratégie d'insertion par étalement de spectres a été utilisée. Au cours de la seconde phase, l'imperceptibilité n'a pas été complètement ignorée, du fait que l'insertion des données est effaçable après l'extraction. Les deux applications principales sont la visualisation 3D de modèles numériques de terrains et de visages. Dans la troisième et dernière phase de ces travaux de thèse, nous avons élargi le problème en essayant de prendre en compte le problème d'assemblage de dalles de niveaux de résolutions différentes sans soudure apparente. Ceci a eté assuré par des fonctions de lissage dans le domaine des ondelettes.
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Mahieddine, Mohammed. "Modélisation, visualisation et animation d'objets 3D : Approche orientée objets." nice, 1991. http://www.theses.fr/1991NICE4496.
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L'objectif de cette thèse est d'étudier l'application de l'approche orientée objets pour la modélisation, la visualisation et l'animation d'objets graphiques en 3 dimensions. Une première phase de cette étude a consiste en la construction d'une extension orientée objets de standards graphiques existants. Pour la construction du graphe d'héritage des classes, une méthode nouvelle est présentée qui consiste à utiliser a la fois l'héritage comportemental et l'héritage implémentationnel. Une extension orientée objets des systèmes core et cgi est présentée pour illustrer ces idées. Une étude exhaustive des méthodes de modélisation des courbes, des surfaces et des solides a permis de montrer l'intérêt des classes et de l'héritage pour réduire la difficulté de confection d'un logiciel de modélisation d'objets géométriques 3d. En ce qui concerne la visualisation des objets, nous montrons les avantages et les limites de l'approche orientée objets pour l'élimination des faces cachées, la manipulation des couleurs et le rendu réaliste (lancer de rayons). Nous montrons ensuite comment décrire l'animation des objets avec les concepts de classes et d'héritage et nous comparons cette approche avec celle des acteurs. La validation de cette approche a consiste à réaliser une application d'animation de robots articules en c++ sous x window. Ce travail démontre que la méthodologie orientée objets permet d'avoir une approche unifiée a la fois pour la modélisation géométrique, la visualisation des objets graphiques et pour leur animation
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Rozendaal, Ross. "Interactive visualisation using 3D graphics : an archaeological case study." Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/4980.
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Bibliography: leaves 82-84.The methods of displaying data from archaeological surveys are of considerable importance in representing realistic impressions of archaeological sites that few people are able to visit. In many cases, further study of a site is not possible at the location of the site. This would require that the surveyed data of the site be displayed in such a way as to be accurate and realistic as well as including interactive tools, enabling further studies. Traditional displays of archaeological data have been either in textual form or in the conventional hardcopy form of maps and drawings. With the advent of computers and computer graphics alternative methods of displaying the data have become possible. 3D graphics have become an important method of displaying archaeological data. In 1995 and 1996 the Department of Geomatics at the University of Cape Town participated in the survey of the 3.6 million year old hominid footprints in Tanzania. The survey was required for the documentation and study of the footprints. In order to facilitate this in 3D graphics, software packages that allowed user interactive tools to be included in the display had to be investigated. Methods of displaying the data also had to be investigated. Java3D was selected to create the 3D models and user interactive tools that included measurement tools, gradient tools and profile tools. These tools were created for the Laetoli footprints but were applicable in other archaeological displays as well.
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Taylor, Simon. "3D visualisation of the laetoli footprints on the internet." Master's thesis, University of Cape Town, 2000. http://hdl.handle.net/11427/4979.
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Kabil, Alexandre. "CyberCOP 3D : visualisation 3D interactive et collaborative de l'état de sécurité d'un système informatique." Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0166.
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L’objectif de la thèse était d’étudier l’utilisation d’Environnements Virtuels Collaboratifs (EVC) pour l’analyse de l’état de sécuritéde systèmes informatiques, aussi appelée la Cyber Situational Awareness (CSA). Après avoir étudié les modèles et outils de la CSA, nous avons pu visiter les Security Operations Center (SOCs) de quatre partenaires industriels de la Chaire Cyber CNI, afin de mieux cerner les besoins et attentes des cyber analystes. Ces visites ont été effectuées dans le cadre d’un protocole de l’analyse de l’activité collaborative et nous ont permises de proposer un modèle, le CyberCOP 3D. En nous basant sur notre modèle ainsi que sur une modélisation du rançongiciel WannaCry, nous avons développé un EVC pour la cybersécurité ainsi qu’un moteur de scénarisation simplifié permettant à des utilisateurs de concevoir leurs propres scénarios d’analyse d’alertes. Nous avons effectué une évaluation de l’utilisabilité d’un environnement virtuel pour l’analyse d’alertes auprès d’utilisateurs non-experts en cybersécuritéThe aim of this thesis was to study the use of Collaborative Virtual Environments (CVE) for the analysis of the state of security of computer systems, also called Cyber Situational Awareness (CSA). After studying CSA’s models and tools, we have had the opportunity to visit the Security Operations Centers (SOCs) of four industrial partners of the CyberCNI chair, in order to better understand the needs and expectations of cyber analysts. These visits were made as part of a collaborative activity analysis protocol and have allowed us to propose a model, the 3D Cyber-COP. Based on this model and a model of the WannaCry ransomware, we have developed a CVE and a simplified scenario engine that allows users to design their own alert analysis scenarios. We have also performed a usability evaluation of a virtual environment for alert analysis, with a panel of novice users
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Trellet, Mikael. "Exploration et analyse immersives de données moléculaires guidées par la tâche et la modélisation sémantique des contenus." Thesis, Université Paris-Saclay (ComUE), 2015. http://www.theses.fr/2015SACLS262/document.
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En biologie structurale, l’étude théorique de structures moléculaires comporte quatre activités principales organisées selon le processus séquentiel suivant : la collecte de données expérimentales/théoriques, la visualisation des structures 3d, la simulation moléculaire, l’analyse et l’interprétation des résultats. Cet enchaînement permet à l’expert d’élaborer de nouvelles hypothèses, de les vérifier de manière expérimentale et de produire de nouvelles données comme point de départ d’un nouveau processus.L’explosion de la quantité de données à manipuler au sein de cette boucle pose désormais deux problèmes. Premièrement, les ressources et le temps relatifs aux tâches de transfert et de conversion de données entre chacune de ces activités augmentent considérablement. Deuxièmement, la complexité des données moléculaires générées par les nouvelles méthodologies expérimentales accroît fortement la difficulté pour correctement percevoir, visualiser et analyser ces données.Les environnements immersifs sont souvent proposés pour aborder le problème de la quantité et de la complexité croissante des phénomènes modélisés, en particulier durant l’activité de visualisation. En effet, la Réalité Virtuelle offre entre autre une perception stéréoscopique de haute qualité utile à une meilleure compréhension de données moléculaires intrinsèquement tridimensionnelles. Elle permet également d’afficher une quantité d’information importante grâce aux grandes surfaces d’affichage, mais aussi de compléter la sensation d’immersion par d’autres canaux sensorimoteurs.Cependant, deux facteurs majeurs freinent l’usage de la Réalité Virtuelle dans le domaine de la biologie structurale. D’une part, même s’il existe une littérature fournie sur la navigation dans les scènes virtuelles réalistes et écologiques, celle-ci est très peu étudiée sur la navigation sur des données scientifiques abstraites. La compréhension de phénomènes 3d complexes est pourtant particulièrement conditionnée par la capacité du sujet à se repérer dans l’espace. Le premier objectif de ce travail de doctorat a donc été de proposer des paradigmes navigation 3d adaptés aux structures moléculaires complexes. D’autre part, le contexte interactif des environnements immersif favorise l’interaction directe avec les objets d’intérêt. Or les activités de collecte et d’analyse des résultats supposent un contexte de travail en "ligne de commande" ou basé sur des scripts spécifiques aux outils d’analyse. Il en résulte que l’usage de la Réalité Virtuelle se limite souvent à l’activité d’exploration et de visualisation des structures moléculaires. C’est pourquoi le second objectif de thèse est de rapprocher ces différentes activités, jusqu’alors réalisées dans des contextes interactifs et applicatifs indépendants, au sein d’un contexte interactif homogène et unique. Outre le fait de minimiser le temps passé dans la gestion des données entre les différents contextes de travail, il s’agit également de présenter de manière conjointe et simultanée les structures moléculaires et leurs analyses et de permettre leur manipulation par des interactions directes.Notre contribution répond à ces objectifs en s’appuyant sur une approche guidée à la fois par le contenu et la tâche. Des paradigmes de navigation ont été conçus en tenant compte du contenu moléculaire, en particulier des propriétés géométriques, et des tâches de l’expert, afin de faciliter le repérage spatial et de rendre plus performante l’activité d’exploration. Par ailleurs, formaliser la nature des données moléculaires, leurs analyses et leurs représentations visuelles, permettent notamment de proposer à la demande et interactivement des analyses adaptées à la nature des données et de créer des liens entre les composants moléculaires et les analyses associées. Ces fonctionnalités passent par la construction d’une représentation sémantique unifiée et performante rendant possible l’intégration de ces activités dans un contexte interactif uniqueIn structural biology, the theoretical study of molecular structures has four main activities organized in the following scenario: collection of experimental and theoretical data, visualization of 3D structures, molecular simulation, analysis and interpretation of results. This pipeline allows the expert to develop new hypotheses, to verify them experimentally and to produce new data as a starting point for a new scenario.The explosion in the amount of data to handle in this loop has two problems. Firstly, the resources and time dedicated to the tasks of transfer and conversion of data between each of these four activities increases significantly. Secondly, the complexity of molecular data generated by new experimental methodologies greatly increases the difficulty to properly collect, visualize and analyze the data.Immersive environments are often proposed to address the quantity and the increasing complexity of the modeled phenomena, especially during the viewing activity. Indeed, virtual reality offers a high quality stereoscopic perception, useful for a better understanding of inherently three-dimensional molecular data. It also displays a large amount of information thanks to the large display surfaces, but also to complete the immersive feeling with other sensorimotor channels (3D audio, haptic feedbacks,...).However, two major factors hindering the use of virtual reality in the field of structural biology. On one hand, although there are literature on navigation and environmental realistic virtual scenes, navigating abstract science is still very little studied. The understanding of complex 3D phenomena is however particularly conditioned by the subject’s ability to identify themselves in a complex 3D phenomenon. The first objective of this thesis work is then to propose 3D navigation paradigms adapted to the molecular structures of increasing complexity. On the other hand, the interactive context of immersive environments encourages direct interaction with the objects of interest. But the activities of: results collection, simulation and analysis, assume a working environment based on command-line inputs or through specific scripts associated to the tools. Usually, the use of virtual reality is therefore restricted to molecular structures exploration and visualization. The second thesis objective is then to bring all these activities, previously carried out in independent and interactive application contexts, within a homogeneous and unique interactive context. In addition to minimizing the time spent in data management between different work contexts, the aim is also to present, in a joint and simultaneous way, molecular structures and analyses, and allow their manipulation through direct interaction.Our contribution meets these objectives by building on an approach guided by both the content and the task. More precisely, navigation paradigms have been designed taking into account the molecular content, especially geometric properties, and tasks of the expert, to facilitate spatial referencing in molecular complexes and make the exploration of these structures more efficient. In addition, formalizing the nature of molecular data, their analysis and their visual representations, allows to interactively propose analyzes adapted to the nature of the data and create links between the molecular components and associated analyzes. These features go through the construction of a unified and powerful semantic representation making possible the integration of these activities in a unique interactive context
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El-Aff, Inhab Abdalla. "Visualisation of the electrical activities of the heart in 3D." Thesis, University of Salford, 2009. http://usir.salford.ac.uk/26652/.
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The work described in this Thesis is concerned with developing a technique to visualise the electrical activities of the heart in 3D from ECG signals taken from sensors on the surface of the body. Generating such visualisations can help cardiologists to identify abnormal electrical propagation flows non-invasively. The approach taken has been to develop models for the body and the heart, followed by the implementation of the 'forward' solution, which calculates the body surface potential for excitations within the heart. The results obtained match published results. The 'inverse' solution, which determines the heart electrophysiology from the body surface measurements, was then implemented. Values derived from the 'forward' solution are then used to confirm the accuracy of the 'inverse' solution. The study has led to three improvements to existing approaches: a more realistic model of the heart's conduction system; and more effective solutions to both the 'forward' and 'inverse' calculations used to determine heart electro physiology. The methods that were developed were based on the biological and physiological properties of the heart tissues as well as the working methodology of the Diffusion Tensor Magnetic Resonance Imaging (DT-MRI) scanner. Evaluation of the proposed techniques has been verified using seven methods, which include the location of Purkinje cells, the anatomy of the ventricle conduction system of the human heart, the Myocardium tissues to the Purkinje tissues ratio, the excitation propagation of the conduction system of the ventricles, the excitation isochrones of ventricles of the human heart, the generated body surface potential map and the generated 12 Lead ECG electrograms. A fundamentally new aspect of the work is to extract the conduction system of the ventricles from the DT-MRI providing a more realistic model for this structure, and this process has been accomplished by a semi-automatic manner, where extraction of the conduction system is accomplished with minimum manual processing and some simple image processing techniques. The Monodomain reaction diffusion equation, which is used to model the ventricle excitation propagation, has been updated to include the diffusion of the electrical stimulation in a non-uniform material, which is the more realistic case. The DT-MRI modality was employed for the first time to model the conduction system of the ventricles and to determine the relative non-uniform conductivity distribution inside the heart Myocardium. Unlike previous methods which consider an estimated conduction network for early activation points and assume the Myocardium material to be a uniform material, the new approach provide a more realistic solution for both the modelling of conduction system and the 'forward' solution. The 'inverse' solution is calculated for a localised multiple dipoles (sources) distribution inside the heart Myocardium based on transmembrance potential instead of current density, as currently used. This type of problem is highly illposed as the number of body surface readings is much fewer than the number of the heart dipoles (highly underdetermined). Employing the transmembrance potential reduces the size of the problem to a third of the current density solution and as a consequence it improves the localisation (due to the reduction of the underdeterminity) and reduces the memory usage and computational power to be 1/9 of the current density solution. Three equations have been derived to calculate the transfer matrix of the problem: the first one is for an isotropic source in a homogeneous-isotropic conductor; the second one is for an anisotropic source in a homogeneous-isotropic conductor; and the third one is for any type of source in an inhomogeneous-isotropic conductor. A low resolution version of the 'forward' model has been employed to simulate the 'forward' solution of the heart, and the body surface readings (200, 100, 64 and 32 electrodes) of that model were then used in the 'inverse' solution. Three regularisation techniques have been used to solve the Inverse Problem namely: the Minimum Norm (MN), the Weighted Minimum Norm (WMN) and the Exact Low Resolution Brain Electromagnetic Tomography technique (eLORETA). Results of these methods are compared to the original pacing points (1, 2, 3, 4, and 5 pacing points) which are used in the forward solution. It is concluded that the best results are obtained from the eLORETA method, and a large number of electrodes on the body surface and fewer number of sources leads to better results.
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Treece, Graham Michael. "Volume measurement and surface visualisation in sequential freehand 3D ultrasound." Thesis, University of Cambridge, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.621171.
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Patera, Marianne. "The potential of 3D visualisation technology in art and design education." Thesis, Glasgow School of Art, 2009. http://radar.gsa.ac.uk/4735/.
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This thesis investigates the potential of 3D visualisation technology for learning and teaching in Art and Design higher education. The aim of this research was not merely to employ the 3D technology but also to identify, design and evaluate an appropriate learning and teaching activity. Three empirical studies were conducted as part of this investigation on the topics of: Colour Theory Colour Experience Spatial Understanding The purpose of this study was to evaluate the effectiveness of the learning activity in its entirety, for learners, tutors and institutions. This research demonstrated that different educational topics may require different technological solutions. It proved that the implementation of carefully designed educational technology can enhance current learning, teaching and assessment processes in Art and Design education.
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Reynolds, Hayley Maria. "3D visualisation and analysis of skin lymphatic drainage patterns in melanoma." Thesis, University of Auckland, 2008. http://hdl.handle.net/2292/5792.
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This thesis aimed to improve visualisation and analysis of potential patterns of melanoma spread from the skin to lymph nodes. For this purpose, anatomically based geometric models of the skin and lymph nodes have been created. A three-dimensional (3D) finite element (FE) skin model has been constructed using the Visible Human (VH) male dataset and a Sawbones head and neck model. A discrete lymph node model was also created using the VH dataset. This study has been conducted in collaboration with the SydneyMelanoma Unit (SMU), in Sydney, Australia. Clinicians at the SMU have recorded an extensive lymphoscintigraphy (LS) database, accurately mapping skin lymphatic drainage from over 5000 patients with cutaneous melanoma. The SMU’s entire LS database was mapped from two-dimensional LS images onto the 3D anatomical model. Melanoma sites were mapped onto the skin model using free-form deformation and projection techniques, while draining node fields were mapped onto a reduced lymph node model. Spatial heat maps were created using field fitting to visualise the likelihood that any area of skin would drain to a particular node field, or a specified number of node fields. An interactive skin selection tool was also developed to provide dynamic predictions of the draining node fields from any region of skin. The heat maps and interactive skin selection tool quantified that lymphatic drainage of the torso was highly complex, where the most unpredictable regions were located near Sappey’s lines. Drainage from skin on the upper and lower limbs was the most predictable, almost always draining to ipsilateral axillary and groin node fields respectively. Skin on the head and neck were shown to usually drain to two or more node fields, where the most common node fields were the cervical level II and preauricular node fields. Detailed statistical analysis was then conducted to investigate widely accepted assumptions about lymphatic drainage. Sappey’s lines were shown to be highly inaccurate at predicting lymphatic drainage from the skin of the torso. At least 12.5% of all melanoma sites located on the torso showed drainage across Sappey’s lines, and nearly the entire torso demonstrated ambiguous lymphatic drainage. A multinomial statistical model was fitted to the LS data to investigate whether lymphatic drainage was symmetric about the body’s vertical midline. Results showed that a significant proportion of the skin was likely to have symmetric lymphatic drainage patterns. Asymmetry that was shown within specific regions was likely due to an asymmetric distribution of melanoma sites within that region and/or a sparsity of data. Regions that indicated symmetry were reflected, providing a larger LS dataset to improve the statistical accuracy of drainage predictions. A cluster analysis was conducted using this reflected LS dataset to group regions of skin that drained in a similar manner. Results indicated that the dominant axillary, groin, cervical level II and preauricular node fields drained significant areas of skin. Clustering resulted in division of the torso into regions similar to Sappey’s lines, although an additional cluster formed in the middle of the anterior and posterior torso where predominantly ambiguous lymphatic drainage occurred. Confidence intervals were calculated using non-parametric bootstrapping to further determine the statistical accuracy of drainage predictions from each of these clusters. This body of research has been presented as four papers, which have either been published or will be submitted to international peer-reviewed journals: 1. Reynolds, H. M., Dunbar, P. R., Uren, R. F., Thompson, J. F. & Smith, N. P. (2007), ‘Mapping melanoma lymphoscintigraphy data onto a 3D anatomically based model’, Annals of Biomedical Engineering, 35:(8),1444-1457. 2. Reynolds, H. M., Dunbar, P. R., Uren, R. F., Blackett, S. A., Thompson, J. F. & Smith, N. P. (2007), ‘Three-dimensional visualisation of lymphatic drainage patterns in patients with cutaneous melanoma’, The Lancet Oncology, 8:(9),806-12. 3. Reynolds, H. M., Smith, N. P., Uren, R. F., Thompson, J. F., & Dunbar, P. R. (2008), ‘Threedimensional visualization of skin lymphatic drainage patterns from the head and neck’, Head & Neck, accepted. 4. Reynolds, H. M., Walker, C. G., Dunbar, P. R., O’Sullivan M. J., Uren, R. F., Thompson, J. F. & Smith, N. P. (2008), ‘Redefining the understanding of skin lymphatic drainage through statistical analysis’, submitted. This work has also been presented at the following three international conferences: 1. 28th Annual International Conference of the IEEE Engineering in Medicine and Biology Society, New York, USA. Aug 30-Sep 3, 2006. 2. Biomedical Engineering Society 2007 Annual Fall Meeting, Los Angeles, California. Sep 26-29, 2007. 3. 6th International Sentinel Node Society Meeting. Sydney, Australia. Feb 18-20, 2008.Whole document restricted until September 2011, but available by request, use the feedback form to request access.
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Wang, Chen. "Large-scale 3D environmental modelling and visualisation for flood hazard warning." Thesis, University of Bradford, 2009. http://hdl.handle.net/10454/3350.
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3D environment reconstruction has received great interest in recent years in areas such as city planning, virtual tourism and flood hazard warning. With the rapid development of computer technologies, it has become possible and necessary to develop new methodologies and techniques for real time simulation for virtual environments applications. This thesis proposes a novel dynamic simulation scheme for flood hazard warning. The work consists of three main parts: digital terrain modelling; 3D environmental reconstruction and system development; flood simulation models. The digital terrain model is constructed using real world measurement data of GIS, in terms of digital elevation data and satellite image data. An NTSP algorithm is proposed for very large data assessing, terrain modelling and visualisation. A pyramidal data arrangement structure is used for dealing with the requirements of terrain details with different resolutions. The 3D environmental reconstruction system is made up of environmental image segmentation for object identification, a new shape match method and an intelligent reconstruction system. The active contours-based multi-resolution vector-valued framework and the multi-seed region growing method are both used for extracting necessary objects from images. The shape match method is used with a template in the spatial domain for a 3D detailed small scale urban environment reconstruction. The intelligent reconstruction system is designed to recreate the whole model based on specific features of objects for large scale environment reconstruction. This study then proposes a new flood simulation scheme which is an important application of the 3D environmental reconstruction system. Two new flooding models have been developed. The first one is flood spreading model which is useful for large scale flood simulation. It consists of flooding image spatial segmentation, a water level calculation process, a standard gradient descent method for energy minimization, a flood region search and a merge process. The finite volume hydrodynamic model is built from shallow water equations which is useful for urban area flood simulation. The proposed 3D urban environment reconstruction system was tested on our simulation platform. The experiment results indicate that this method is capable of dealing with complicated and high resolution region reconstruction which is useful for many applications. When testing the 3D flood simulation system, the simulation results are very close to the real flood situation, and this method has faster speed and greater accuracy of simulating the inundation area in comparison to the conventional flood simulation models
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Dobos, J. "Management and visualisation of non-linear history of polygonal 3D models." Thesis, University College London (University of London), 2015. http://discovery.ucl.ac.uk/1461400/.
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The research presented in this thesis concerns the problems of maintenance and revision control of large-scale three dimensional (3D) models over the Internet. As the models grow in size and the authoring tools grow in complexity, standard approaches to collaborative asset development become impractical. The prevalent paradigm of sharing files on a file system poses serious risks with regards, but not limited to, ensuring consistency and concurrency of multi-user 3D editing. Although modifications might be tracked manually using naming conventions or automatically in a version control system (VCS), understanding the provenance of a large 3D dataset is hard due to revision metadata not being associated with the underlying scene structures. Some tools and protocols enable seamless synchronisation of file and directory changes in remote locations. However, the existing web-based technologies are not yet fully exploiting the modern design patters for access to and management of alternative shared resources online. Therefore, four distinct but highly interconnected conceptual tools are explored. The first is the organisation of 3D assets within recent document-oriented No Structured Query Language (NoSQL) databases. These "schemaless" databases, unlike their relational counterparts, do not represent data in rigid table structures. Instead, they rely on polymorphic documents composed of key-value pairs that are much better suited to the diverse nature of 3D assets. Hence, a domain-specific non-linear revision control system 3D Repo is built around a NoSQL database to enable asynchronous editing similar to traditional VCSs. The second concept is that of visual 3D differencing and merging. The accompanying 3D Diff tool supports interactive conflict resolution at the level of scene graph nodes that are de facto the delta changes stored in the repository. The third is the utilisation of HyperText Transfer Protocol (HTTP) for the purposes of 3D data management. The XML3DRepo daemon application exposes the contents of the repository and the version control logic in a Representational State Transfer (REST) style of architecture. At the same time, it manifests the effects of various 3D encoding strategies on the file sizes and download times in modern web browsers. The fourth and final concept is the reverse-engineering of an editing history. Even if the models are being version controlled, the extracted provenance is limited to additions, deletions and modifications. The 3D Timeline tool, therefore, implies a plausible history of common modelling operations such as duplications, transformations, etc. Given a collection of 3D models, it estimates a part-based correspondence and visualises it in a temporal flow. The prototype tools developed as part of the research were evaluated in pilot user studies that suggest they are usable by the end users and well suited to their respective tasks. Together, the results constitute a novel framework that demonstrates the feasibility of a domain-specific 3D version control.
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Berg, Madeleine Tamsin Lisa. "3D visualisation of melts at the conditions of Earth's deep interior." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20400.
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Constraining the behaviour of small fractions of partial melt in a solid silicate matrix has been the focus of numerous experimental petrology studies over several decades, and is an important factor in constraining upper mantle rheology, melt extraction at mid-ocean ridges and mechanisms of core formation in the early solar system. Deformation of partially molten rock has been observed to change melt geometry, and may enhance permeability and interconnectivity of melt otherwise trapped in a solid silicate matrix, although it is uncertain how applicable results of high strain-rate laboratory experiments are to the real Earth. The addition of deformation precludes attainment of textural equilibrium, complicating textural analysis, which has previously relied on extrapolation of 3D textures from quenched and polished 2D sections for hydrostatically annealed samples. X-ray computed tomography gives the potential to visualise sample textures directly in three dimensions, and is becoming popular as a complementary technique for textural analysis in petrologic studies. The aim of this project has been to develop techniques to improve visualisation of small fractions of partial melt within a solid silicate matrix using X-ray CT, to examine textures of various partially molten systems at high PT in hydrostatic, and dynamically deforming systems. Experiments carried out in the FeS-melt, solid olivine system have examined the potential for deformation-enhanced percolation of core forming melts before the onset of silicate melting. Access to the newly designed rotational Paris-Edinburgh Cell (roPEC/rotoPEC) equipment has allowed us to carry out controlled, torsional deformation experiments under PT conditions applicable to planetary interiors. Experiments conducted at lower strain-rates over longer duration than in previously published studies show that deformation enhances connectivity at low melt fractions, at strain-rates down to 10-6s-1. This is in contrast to earlier work suggesting melt textures are unaffected at strain-rates below 10-5s-1. Quenched melt networks have been fully characterised in 3D using multi-scale CT, with voxel sizes down to 70nm for small sample sub-volumes. Results suggest segregation of metallic melt below the silicate solidus could be an efficient process, and should be taken into account in geochemical models of planetary evolution. Experiments on basaltic melt in a solid silicate matrix were conducted in application to upper mantle melting. A heavy element, hafnium, was added to the basaltic glass starting composition to enhance contrast between the basalt and olivine phases during CT scans. In-house micro-CT equipment was used to visualise post-quench run products of hydrostatic and deformation experiments. The doping technique was successful for long-duration, high temperature hydrostatic experiments. Some issues with undissolved / re-precipitated HfO¬2 crystals complicated tomographic imaging of partial melt textures in a number of experiments, particularly those carried out on the rotoPEC equipment, limiting comparison between samples. The doping technique requires further adjustment, but is shown to be a viable way to improve visibility of basaltic melt without significantly affecting melt texture. The X-ray transparent design and fully rotating top and bottom anvils of the rotoPEC allow X-ray tomography to be carried out in-situ while experiments are in progress, enabling collection of 4D datasets. During this project, the rotoPEC equipment was incorporated into two different synchrotron beamlines, to carry out time-resolved studies of textural development within samples of varying composition. The migration of gold melt along fractures with a BN matrix was imaged using 2D radiography, in combination with repeated 3D tomography to fully characterise the 3D fracture geometry. This allowed melt migration velocity to be estimated directly from in-situ observations. These techniques could be developed further to constrain melt migration processes quantitatively for a number of geological systems in the near future.
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Dillenseger, Jean-Louis. "Visualisation Scientifique en médecine.Application à la visualisation de l'anatomie et à la visualisation en épileptologie clinique." Habilitation à diriger des recherches, Université Rennes 1, 2003. http://tel.archives-ouvertes.fr/tel-00130932.
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En médecine, le rôle de l'image est primordial. Depuis la renaissance, l'image a été un des vecteurs principaux de la transmission du savoir. Plus récemment, l'essor des techniques d'imageries tridimensionnelles n'a fait qu'étendre l'importance de l'image à la plupart des disciplines et des procédures médicales. Tout naturellement donc, la médecine a représenté un des domaines d'application privilégiés de la visualisation scientifique. Mes travaux de recherche s'inscrivent directement dans cette discipline de la visualisation scientifique et se présentent sous la forme de solutions de représentations originales apportées et associées à certaines problématiques médicales.Pour cela, une réflexion sur l'outil de visualisation a été menée afin de proposer un cadre bien défini qui puisse guider l'élaboration d'un outil de représentation répondant à une discipline et à une problématique particulière. Le point le plus original de cette réflexion concerne un essai de formalisation de l'évaluation de la performance des outils de visualisation.
Deux grands domaines d'application ont justement permis de démontrer la pertinence de ce cadre général de la visualisation :
- La visualisation générale de l'anatomie avec, dans un premier temps, la conception d'un outil générique de visualisation de données médicale, le lancer de rayons multifonctions. Cet outil a été ensuite étendu selon deux axes de recherche, d'une part l'intégration de modèles de connaissances dans la procédure de synthèse d'images et d'autre part, l'imagerie interventionnelle et plus particulièrement des applications en urologie.
- Les apports de la visualisation pour l'interprétation des données recueillies sur le patient épileptique et plus particulièrement l'élaboration d'outils complémentaires permettant une analyse progressive des mécanismes et structures impliqués dans la crise.
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Ekberg, Fredrik. "An approach for representing complex 3D objects in GIS applied to 3D properties." Thesis, University of Gävle, Department of Technology and Built Environment, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-139.
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The main problem that is addressed in this thesis is how to represent complex three-dimensional objects in GIS in order to render a more realistic representation of the real world. The goal is to present an approach for representing complex 3D objects in GIS. This is achieved by using commercial GIS (ArcGIS), applied to 3D properties. In order to get a clear overview of the state-of-the-art of 3D GIS and the current 3D cadastral situation a literature study was carried out. Based on this overview it can be concluded that 3D GIS still is in its initial phase. Current 3D GIS developments are mainly in the area of visualisation and animation, and almost nothing in the area of spatial analysis and attribute handling. Furthermore, the literature study reveals that no complete solution has been introduced that solves the problems involved in 3D cadastral registration. In several countries (e.g. Sweden, Denmark, Norway, Netherlands, Israel, and Australia) 3D properties exists in a juridical framework, but technical issues such as how to represent, store, and visualize 3D properties has not yet been solved. Some countries (Sweden, Norway, and Australia) visualize the footprints of 3D property units in a base map. This approach partly solves some technical issues, but can only represent 3D objects in a 2.5D environment. Therefore, research in how to represent complex objects in GIS as ‘true’ 3D objects is of great need.
This thesis will emphasize MultiPatch as a geographic representation method to represent complex 3D objects in GIS. A case study will demonstrate that complex objects can be visualized and analysed in a commercial GIS, in this case ArcGIS. Most commercial GIS software available on the market applies a 2.5D approach to represent 3D objects. The 2.5D approach has limitations for representing complex objects. There is therefore a need of finding new approaches to represent complex objects within GIS. The result shows that MultiPatch is not an answer to all the problems within 3D GIS but a solution to some of the problems. It still requires a lot of research in the field of 3D GIS, especially in development of spatial analysis capabilities.
Det huvudsakliga problemet i denna uppsats är hur komplexa tre-dimensionella objekt kan representeras i GIS för att återge verkligheten mer realistiskt. Målet är att presentera ett tillvägagångssätt för att representera komplexa 3D-objekt i GIS. Detta har uppnåtts genom att använda ett kommersiellt GIS tillämpat på 3D-fastigheter. En litteraturstudie har genomförts för att erhålla en klar översikt över det senaste inom 3D-GIS och över den aktuella situationen inom 3D-fastigheter. Grundat på översikten kan slutsatsen dras att 3D-GIS bara är i sin begynnelsefas. Den aktuella utvecklingen inom 3D-GIS har huvudsakligen fokuserat på visualisering och animering och nästan ingenting inom rumsliga analysmetoder och hantering av attribut. Litteraturstudien visar också att ingen fullständig lösning för de problem som finns inom 3D-fastighetsregistrering har introducerats. I flera länder, t.ex. Sverige, Danmark, Norge, Nederländerna, Israel och Australien, existerar 3D-fastigheter idag i juridiska termer, men de tekniska problemen som t.ex. hur 3D-fastigheter ska representeras, lagras och visualiseras har inte ännu lösts. Vissa länder (Sverige, Norge och Australien) visualiserar idag en projektion av 3D-fastigheterna på en fastighetskarta. Den här metoden löser endast några av de tekniska problemen och kan endast representera 3D-objekt i en 2,5D-miljö. Därför är forskning inom hur komplexa objekt kan representeras i GIS som s.k. ”sann” 3D av betydelse.
Den här uppsatsen framhäver MultiPatch som en datatyp för att representera komplexa 3D-objekt i GIS. En fallstudie visar att komplexa objekt kan visualiseras och analyseras i ett kommersiellt GIS, i det här fallet ArcGIS. De flesta kommersiella GIS som är tillgängliga på marknaden använder 2,5D-metoden för att representera 3D-objekt. 2,5D-metoden har vissa begränsningar för att representera komplexa objekt och därför finns det ett behov att finna nya tillvägagångssätt för att representera komplexa objekt inom GIS. Resultaten kommer att visa att MultiPatch inte är någon fullständig lösning till alla problem inom 3D-GIS men en lösning på några av problemen. Det krävs fortfarande mycket forskning inom 3D-GIS, särskilt inom utveckling av rumsliga analysmetoder.
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Sjölund, Albin. "3D karta : visualisering av logistikdata." Thesis, Mittuniversitetet, Institutionen för informationssystem och –teknologi, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-36579.
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Data can be presented in many different ways depending on the type of data and the purpose of the presentation. Sogeti has customers with logistic data that they want to use to show their customers and visitors in their office what they are working with. The goal of this project was to take this data and come up with a way of visualizing it on an interactive 3D map and create a proof of concept to show the idea of how the basic functions of the map could work. Three different frameworks for creating 3D maps were compared and based on their functions and after testing them Arcgis were chosen for the implementation of the proof of concept. The implementation was then tested to see how adding more objects to the map affected the performance of the implementation. Frameworks for further development were looked in to but did not affect the decision of choosing a framework for the proof of concept.Data kan visas på flera olika sätt beroende på vilken typ av data det är och syftet med det som ska visas. Sogeti har kunder med logistik data som de vill använda för att visa sina kunder och besökare vad de arbetar med. Målet med det här projektet var att använda den här datan och visualisera den på en interaktiv 3D karta och skapa ett proof of concept för att visa hur basfunktionerna för kartan kan fungera. Tre olika ramverk för att skapa 3D kartor jämfördes och baserat på deras funktioner och efter att ha testat dem så valdes Arcgis till implementationen av ett proof of concept. Implementationen testades sedan för att se hur prestandan påverkades när fler objekt lades till kartan. Ramverk för att fortsatt utveckling tittades på men påverkade inte valet för att välja ett ramverk till proof of concept.
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Wang, Nan. "Visualisation et interaction pour l’exploration et la perception immersive de données 3D." Thesis, Paris, ENMP, 2012. http://www.theses.fr/2012ENMP0090/document.
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L'objet de cette thèse est la perception dans les environnements immersifs de jeux de données complexes, une des applications est la visualisation scientifique de données volumiques scalaires issues de simulations de modèles physiques. Un exemple classique de ceci est la distribution de températures à l'intérieur d'un habitacle de véhicule.Dans la première partie de ce travail, notre objectif est d'étudier les limites perceptives dans le cadre d'un rendu volumétrique de données scientifiques dans un système de réalité virtuelle offrant la vision en stéréoscopie, et le suivi du point de vue de l'utilisateur. Nous étudions l'effet sur la perception de l'utilisateur de trois facteurs principaux : la taille des points utilisés pour le rendu, la densité du nuage de points, et enfin la position par rapport à l'utilisateur du premier plan de coupe. Nous présentons une étude dans laquelle une tâche de pointage est proposée à un ensemble d'utilisateurs. Les déplacements de celui-ci ainsi que les performances de pointage sont mesurées. L'étude a permis d'évaluer l'impact des paramètres de rendu du nuage de points et proposer un rendu améliorant la perception.La seconde partie du travail propose d'ajouter une dimension interactive à la première approche en permettant à l'utilisateur d'explorer plus activement la scène. L'hypothèse d'une meilleure compréhension des données par l'action est ici mise en avant. Nous évaluons une méthode d'interaction et quatre méthodes de rendu associées. L'approche proposée est de n'afficher qu'un sous ensemble des données volumiques, en l'occurrence des isosurfaces, et de permettre à l'utilisateur de naviguer par une gestuelle naturelle et interactive dans l'ensemble des isosurfaces du jeu de données explorées, dans cadre de manipulation directe. Une nouvelle étude est proposée, dans laquelle l'utilisateur doit effectuer une tâche de recherche et de pointage d'une propriété locale dans un jeu de températures 3D. Cette étude a permis de choisir une méthode de rendu adaptée à l'affichage immersif d'isosurfaces et de valider l'approche interactive pour l'exploration de donnéesThe objective in this case is not only to be realistic, but also to provide new and intelligible ways of model representation. This raises new issues in data perception. The question of perception of complex data, especially regarding visual feedback, is an open question, and it is the subject of this work. This PhD thesis studied the human perception in Immersive Virtual Environments of complex datasets, one of the applications is the scientific visualization of scalar values stemming from physics models, such as temperature distribution inside a vehicle prototype.The objective of the first part is to study the perceptive limits of volumetric rendering for the display of scientific volumetric data, such as a volumetric temperature distribution rendering using point cloud. We investigate the effect on the user perception of three properties of a point cloud volumetric rendering: point size, cloud density and near clipping plane position. We present an experiment where a series of pointing tasks are proposed to a set of users. User behavior and task completion time are evaluated during the test. The study allowed to choose the most suitable combination of these properties, and provided guidelines for volumetric data representation in VR immersive systems.In the second part of our work, we evaluate one interaction method and four display techniques for exploring volumetric datasets in virtual reality immersive environments. We propose an approach based on the display of a subset of the volumetric data, as isosurfaces, and an interactive manipulation of the isosurfaces to allow the user to look for local properties in the datasets. We also studied the influence of four different rendering techniques for isosurface rendering in a virtual reality system. The study is based on a search and point task in a 3D temperature field. User precision, task completion time and user movement were evaluated during the test. The study allowed to choose the most suitable rendering mode for isosurface representation, and provided guidelines for data exploration tasks in immersive environments
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Lamontagne, Jerry. "Élaboration d'une interface graphique pour la visualisation 3D de modèles d'éléments finis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0015/MQ56757.pdf.
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Wang, Nan. "Visualisation et interaction pour l'exploration et la perception immersive de données 3D." Phd thesis, Ecole Nationale Supérieure des Mines de Paris, 2012. http://pastel.archives-ouvertes.fr/pastel-00821004.
Full textAbstract:
L'objet de cette thèse est la perception dans les environnements immersifs de jeux de données complexes, une des applications est la visualisation scientifique de données volumiques scalaires issues de simulations de modèles physiques. Un exemple classique de ceci est la distribution de températures à l'intérieur d'un habitacle de véhicule.Dans la première partie de ce travail, notre objectif est d'étudier les limites perceptives dans le cadre d'un rendu volumétrique de données scientifiques dans un système de réalité virtuelle offrant la vision en stéréoscopie, et le suivi du point de vue de l'utilisateur. Nous étudions l'effet sur la perception de l'utilisateur de trois facteurs principaux : la taille des points utilisés pour le rendu, la densité du nuage de points, et enfin la position par rapport à l'utilisateur du premier plan de coupe. Nous présentons une étude dans laquelle une tâche de pointage est proposée à un ensemble d'utilisateurs. Les déplacements de celui-ci ainsi que les performances de pointage sont mesurées. L'étude a permis d'évaluer l'impact des paramètres de rendu du nuage de points et proposer un rendu améliorant la perception.La seconde partie du travail propose d'ajouter une dimension interactive à la première approche en permettant à l'utilisateur d'explorer plus activement la scène. L'hypothèse d'une meilleure compréhension des données par l'action est ici mise en avant. Nous évaluons une méthode d'interaction et quatre méthodes de rendu associées. L'approche proposée est de n'afficher qu'un sous ensemble des données volumiques, en l'occurrence des isosurfaces, et de permettre à l'utilisateur de naviguer par une gestuelle naturelle et interactive dans l'ensemble des isosurfaces du jeu de données explorées, dans cadre de manipulation directe. Une nouvelle étude est proposée, dans laquelle l'utilisateur doit effectuer une tâche de recherche et de pointage d'une propriété locale dans un jeu de températures 3D. Cette étude a permis de choisir une méthode de rendu adaptée à l'affichage immersif d'isosurfaces et de valider l'approche interactive pour l'exploration de données.
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Gong, Weizhong. "Modular-MPC accelerators for cost-effective 3D visualisation based on surface rendering." Thesis, Brunel University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336643.
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Musa, Shahrulniza. "Visualising network security attacks with multiple 3D visualisation and false alert classification." Thesis, Loughborough University, 2008. https://dspace.lboro.ac.uk/2134/14241.
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Increasing numbers of alerts produced by network intrusion detection systems (NIDS) have burdened the job of security analysts especially in identifying and responding to them. The tasks of exploring and analysing large quantities of communication network security data are also difficult. This thesis studied the application of visualisation in combination with alerts classifier to make the exploring and understanding of network security alerts data faster and easier. The prototype software, NSAViz, has been developed to visualise and to provide an intuitive presentation of the network security alerts data using interactive 3D visuals with an integration of a false alert classifier. The needs analysis of this prototype was based on the suggested needs of network security analyst's tasks as seen in the literatures. The prototype software incorporates various projections of the alert data in 3D displays. The overview was plotted in a 3D plot named as "time series 3D AlertGraph" which was an extension of the 2D histographs into 3D. The 3D AlertGraph was effectively summarised the alerts data and gave the overview of the network security status. Filtering, drill-down and playback of the alerts at variable speed were incorporated to strengthen the analysis. Real-time visual observation was also included. To identify true alerts from all alerts represents the main task of the network security analyst. This prototype software was integrated with a false alert classifier using a classification tree based on C4.5 classification algorithm to classify the alerts into true and false. Users can add new samples and edit the existing classifier training sample. The classifier performance was measured using k-fold cross-validation technique. The results showed the classifier was able to remove noise in the visualisation, thus making the pattern of the true alerts to emerge. It also highlighted the true alerts in the visualisation. Finally, a user evaluation was conducted to find the usability problems in the tool and to measure its effectiveness. The feed backs showed the tools had successfully helped the task of the security analyst and increased the security awareness in their supervised network. From this research, the task of exploring and analysing a large amount of network security data becomes easier and the true attacks can be identified using the prototype visualisation tools. Visualisation techniques and false alert classification are helpful in exploring and analysing network security data.
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North, Steve. "Clients' 3D visualisation of construction performance : from s-curves to data surfaces." Thesis, University College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.406399.
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He, Shuang. "Production et visualisation de niveaux de détail pour les modèles 3D urbains." Ecole centrale de Nantes, 2012. http://portaildocumentaire.citechaillot.fr/search.aspx?SC=theses&QUERY=+marie+Durand#/Detail/%28query:%28Id:%270_OFFSET_0%27,Index:1,NBResults:1,PageRange:3,SearchQuery:%28CloudTerms:!%28%29,ForceSearch:!t,Page:0,PageRange:3,QueryString:%27Shuang%20he%27,ResultSize:10,ScenarioCode:theses,ScenarioDisplayMode:display-standard,SearchLabel:%27%27,SearchTerms:%27Shuang%20he%27,SortField:!n,SortOrder:0,TemplateParams:%28Scenario:%27%27,Scope:%27%27,Size:!n,Source:%27%27,Support:%27%27%29%29%29%29.
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Les modèles 3D urbains sont de plus en plus utilisés dans une large variété d'applications urbaines, comme plates-formes d’intégration et de visualisation de diverses informations. Ce travail porte sur la production et la visualisation de niveaux de détail pour les modèles 3D urbains, en vue de leur utilisation dans des applications SIG. Ce travail propose une solution hybride pour la production de niveaux de détail pour les modèles 3D urbains en utilisant une combinaison de techniques : l'extrusion, l'intégration, la généralisation et la modélisation procédurale. La condition préalable à l’utilisation de notre solution est de disposer des données (comme les empreintes au sol des bâtiments provenant du cadastre) pour générer des modèles volumiques de bâtiments et des données (comme le réseau routier, division administrative, etc. ) pour diviser la ville en unités significatives. Il peut également tirer avantage de l’utilisation d’autres modèles 2D et 3D d’objets de la ville autant que possible. Parce que ces exigences peuvent être remplies à faible coût, la solution peut être facilement adoptée. L’objectif principal de ce travail porte sur les techniques et les algorithmes de généralisation. Un cadre de la généralisation est proposé sur la base du diviser pour régner, réalisé par subdivision de la couverture du sol et la généralisation de cellules. Le cadre permet la généralisation à l’échelle de la ville entière vers des modèles plus abstraits et facilite la généralisation à l’échelle locale en regroupant les objets selon une subdivision hiérarchique de la ville. Une mise en œuvre de la généralisation à l’échelle de la ville est réalisée sur la base de ce cadre. Une approche basée sur l’empreinte au sol des bâtiments est développée pour généraliser les groupes de bâtiments 3D, qui peut être utilisée pour la généralisation à l’échelle locale. En outre, en utilisant les niveaux de détail des modèles 3D produits par la solution proposée, trois exemples de visualisation sont donnés pour démontrer quelques-unes des utilisations possibles : une visualisation multi-échelle, une visualisation « focus + contexte », ainsi qu’une visualisation dépendant de la vue3D city models have been increasingly used in a variety of urban applications as platforms to integrate and visualize diverse information. This work addresses level-of-detail production and visualization of 3D city models, towards their use in GIS applications. This work proposes a hybrid solution to LoD production of 3D city models, using a combination of techniques: extrusion, integration, generalization, and procedural modeling. The prerequisite for using our solution is to have data (like 2D cadastral buildings) for generating city coverage volumetric building models and data (like road network, administrative division, etc) for dividing the city into meaningful units. It can also gain advantage from using other accessible 2D and 3D models of city objects as many as possible. Because such requirements can be fulfilled at low cost, the solution may be easily adopted. The main focus of this work is placed on generalization techniques and algorithms. A generalization framework is proposed based on the divide-and-conquer concept, realized by land cover subdivision and cell-based generalization. The framework enables city scale generalization towards more abstract city models, and facilitates local scale generalization by grouping city objects according to city cells. An implementation of city scale generalization is realized based on the framework. A footprint-based approach is developed for generalizing 3D building groups at medium LoD, which can be used for local scale generalization. Moreover, using the LoD 3D city models produced by the proposed solution, three visualization examples are given to demonstrate some of the potential uses: multi-scale, focus + context, and view-dependent visualization
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ROCHA, CRISTINA. "Visualisation scientifique en epilepsie : fusion de signaux electroencephalographiques en imagerie morphologique 3d." Rennes 1, 1997. http://www.theses.fr/1997REN10080.
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Cette these s'inscrit dans le cadre de la visualisation scientifique. Le but de ce travail est de faciliter l'interpretation de donnees provenant de l'imagerie medicale 3d et de mesures electrophysiologiques. Cet objectif necessite: i) de bien connaitre les donnees a representer, ii) d'etudier les modes de representation possibles, iii) d'evaluer leur faisabilite. Sur le plan clinique, notre domaine d'application est l'epilepsie qui fournit un exemple riche et complexe de representation, si l'on considere la quantite importante de donnees, leur multidimensionnalite et leur heterogeneite (les signaux et les images qui apportent des informations morphologiques et fonctionnelles). Sur le plan theorique, nous menons une reflexion sur les donnees en visualisation scientifique. Dans un premier temps, une caracterisation de certains aspects (les objets, les signaux, les variables et les traitements) est effectuee. Cette caracterisation conduit a distinguer les representations naturelles de celles qui permettent de codifier les phenomenes mesures ne possedant pas de support spatial de representation. Dans un second temps, une visualisation de ces phenomenes est proposee. La methode utilisee pour effectuer le rendu de l'image est une adaptation de la methode du lancer de rayons. Enfin, les problemes de perception visuelle sont examines, en particulier sous l'aspect de la couleur. Une procedure de visualisation de donnees multimodalite comporte necessairement une etape de recalage qui fournit les parametres d'une transformation permettant de mettre en correspondance les donnees. Le choix de cette transformation doit s'effectuer en fonction de l'application visee. Dans ce travail, l'application - fusion de donnees image et de donnees signal - s'effectue par l'intermediaire du seul element, de nature anatomique, qui leur est commun: les electrodes d'acquisition des signaux. La solution proposee ici est un recalage point/surface. Les resultats de visualisation presentes sont obtenus en dimension 2 et 3: ils s'expriment en termes de nappes spatio-temporelles (pour les reseaux lineaires de capteurs) et en termes de cartographies pour les reseaux surfaciques. La construction de nappes 3d est basee sur les resultats de la transformee temps-frequence et de la decomposition par ondelettes. En 3d, l'introduction de la transparence et de la composition de couleurs et d'opacites permet la visualisation de resultats multisignaux multistructures
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Coertze, Johannes A. "Visualisation and manipulation of 3D patient-specific bone geometry using augmented reality." Master's thesis, Faculty of Health Sciences, 2020. http://hdl.handle.net/11427/32211.
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Computer-mediated reality technologies have the potential to improve the imageguided surgery (IGS) workflow; specifically, pre-surgical planning, intra-operative guidance, post-surgical assessment, and rehabilitation. Augmented reality (AR), a form of computer-mediated reality, uses an electronic display or projection module to add a hologram in the user's field of view (FOV). For intra-operative guidance, AR could aid in reducing the cognitive overload experienced by clinicians due to integrating multi-modal imaging data from several sources while performing the intervention on the patient. Three AR HMD systems have been developed to explore the capabilities of the Microsoft HoloLens as an AR HMD to be used in developing an AR HMD medical system. The three AR HMD systems required different software and hardware system architectures, however, each of the AR HMD system's software applications has been developed in Unity combined with the Mixed Reality Toolkit (MRTK). Each of the AR HMD systems implemented different registration techniques to localize the virtual object in the real-world coordinate system. The registration techniques were user calibration alignment to identified anatomical landmarks, fiducial marker tracking, and markerless tracking. For user calibration with anatomical landmarks, the MRTK was manipulated to allow alignment of the virtual object. For fiducial registration, the Vuforia Software Development Kit (SDK) was added to assess the alignment and spatial anchoring of the virtual object as specified. Finally, the Leap Motion Controller (LMC) and Leap's Orion SDK was used for exploring markerless tracking. The AR HMD systems developed enabled performance assessments, and alignment errors were identified during trials of the three systems. Most notably the location drift of the 3D virtual object in the spatial space due to the clinician moving around the registered location. This project entailed preliminary development towards the AR HMD medical system to create an in-vivo view of 3D patient-specific bone geometries as a hologram in the clinician's FOV.
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Prat, Sylvain. "Compression et visualisation de grandes scènes 3D par représentation à base topologique." Rennes 1, 2007. http://www.theses.fr/2007REN1S039.
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Si les applications de visualisation de scènes 3D sont maintenant légion depuis l'avènement de cartes graphiques 3D puissantes permettant un rendu 3D temps-réel, le rendu de grandes scènes 3D reste toujours problématique du fait du trop grand nombre de primitives 3D à traiter pendant le court laps de temps s'écoulant entre deux images successives. D'autre part, la démocratisation d'internet dans les foyers créé de nouveaux besoins, et notamment celui de naviguer dans de grands environnements 3D au travers d'un réseau. Les applications sont en effet nombreuses : jeu vidéo, tourisme virtuel, géolocalisation (GPS), architecture virtuelle, imagerie médicale 3D. . . Dans ce cadre, les utilisateurs échangent des informations concernant l'univers virtuel au travers du réseau. Le sujet de cette thèse s'inscrit entre ces deux problématiques. Nous nous interessons au cas particulier de la visualisation de villes virtuelles dans un contexte « communiquant » où les données 3D transitent sur le réseau. Ce type d'application soulève deux problèmes majeurs : d'une part, la sélection des données pertinentes à transmettre à l'utilisateur, car il est trop coûteux de transmettre l'intégralité de l'univers virtuel 3D avant le début de la navigation ; d'autre part, la prise en compte des contraintes réseau : faible débit, latence, tolérance aux erreurs. Dans cette thèse, nous proposons plusieurs contributions : une méthode de compression générique permettant notamment de traiter les maillages volumiques, une méthode de construction et de partitionnement de scènes 3D urbaines à partir d'emprises au sol, et une méthode optimisée de construction de surfaces complexes à partir d'une soupe de polygonesIf visualization applications of 3D scenes are now widespread since the advent of powerful 3D graphics cards allowing real-time 3D rendering, the rendering of large 3D scenes remains problematic because of the too many 3D primitives to handle during the short period of time elapsing between two successive image frames. On the other hand, the democratisation of the Internet at home creates new needs, including the need to navigate into large 3D environments through a network. Applications are indeed numerous: video games, virtual tourism, geolocalization (GPS), virtual architecture, 3d medical imaging. . . Within this context, users exchange and share information regarding the virtual environment over the network. The subject of this thesis is in-between these two issues. We are interested in the special case of viewing virtual cities in a "communicating" fashion where 3D data pass over the network. This type of application raises two major problems: first, the selection of relevant data to be transmitted to the user, because it's too expensive to transmit the full 3D environment before the navigation starts; on the other hand, taking into account the network constraints: low bandwidth, latency, error tolerance. In this thesis, we propose several contributions: a generic compression method, suitable for the compression of volume meshes, a method for constructing and partitioning 3D urban scenes from buildings footprints, and an optimized method for building complex surfaces from a polygon soup
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Chan, Warren. "An investigation of 3D visualisation and simulation systems for research and education." Thesis, Glasgow Caledonian University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.688300.
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Tang, Bo. "Image-based rendering for visualisation of 3D scenes in near real-time." Thesis, University of Central Lancashire, 2008. http://clok.uclan.ac.uk/19271/.
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In this research work, a software and hardware prototype for real—time 3D visualisation is developed. The proposed system takes two input videos to interpolate virtual in—between views, which are then combined into 3D videos after processing for viewing on a 3D monitor. The core section of this research work is based on view morphing, a type of image based rendering. The image based rendering is a technique used to render a scene from a number of source images. According to the knowledge of geometric information of captured scenes, the image based rendering technique can be classified into three categories: rendering without geometry, rendering with implicit geometry and rendering with explicit geometry. The view morphing technique, a subset of the second category, requires less geometric information and a few source images of captured scenes. These reduce the complexities of both computation and hardware configuration of the proposed system, moreover, the quality of interpolated virtual in—between views by view morphing technique is good enough for visualisation applications. In this thesis, the research work is presented from two aspects: the algorithmic and the system's points of view separately. The algorithmic development and optimisation consist of the procedures of automatically interpolating virtual in—between views from two source images. The work begun with two cameras calibration with the objective of finding out the geometric relationship in 3D space between the two cameras. Image rectification is followed to project two source images into two parallel planes. This enables to obtain physically valid virtual in—between views and also reduces the computational cost for correspondence estimation. Subsequently, stereo matching is applied to establish feature correspondences between the two rectified source images. A novel feature based correspondence estimation algorithm is proposed to raise the level of the computational efficiency and the reliability. After that, interval interpolation is used to synthesise virtual in—between views. Finally, image derectification is applied to obtain final interpolated virtual in—between views. A novel pseudo real—time 3D visualisation system is proposed in the system development and optimisation. The proposed system has been developed using the TI (Texas Instruments) DM642 EVM board which is a standalone Digital Media Processing board. The system also includes a stereo video capture module consisting of two PAL cameras and the X3D-19 DISPLAY AD 3D display unit for visualisation of 3D video output. The core algorithm utilises images captured from the cameras and generates 6 virtual in—between views using interpolation techniques. The combined views (eight views of 2D images) are displayed on the 3D monitor using a proprietary method developed specifically for X31) monitors. The advantage of the proposed system is that real 3D impressions are able to be visualised in front of the 3D monitor in near real—time without any special glasses. The proposed system has been evaluated on a number of real scenes. The experimental results indicate that the performance of the proposed 3D visualisation system is about 4.7 FPS.
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Widell, Alex. "An expansion of the 3D rendering discussion." Thesis, Konstfack, Inredningsarkitektur & Möbeldesign, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-6282.
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Vitale, Valeria. "Rethinking 3D visualisation : from photorealistic visual aid to multivocal environment to study and communicate cultural heritage." Thesis, King's College London (University of London), 2017. https://kclpure.kcl.ac.uk/portal/en/theses/rethinking-3d-visualisation(7079ff9d-6e19-4335-a3e6-fc53bf69620c).html.
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This research presents the issue of opacity in 3D visualisations of cultural heritage and explains how it prevents 3D technologies from being used to their full extent in an academic context. The impossibility to assess the provenance of the sources, cite references or identify individual contributions make the majority of available 3D models closer to mere illustrations than tools for the study and understanding of the past, regardless the amount of research that has informed the creation of the visual output. An analysis of some of the existing strategies of documentation of 3D visualisations highlights the current lack of a standard, or even a common language, that would make such documentations comparable and cross searchable. This work suggests the use of a simple, sustainable and well-established technology as Linked Open Data, together with a tailored domain ontology, as a possible approach. The use of the synthetic and formalised vocabulary of an ontology, with its classes and properties, is used experimentally, as a proof of concept, to document the 3D visualisation of an ancient building, the Iseum in Pompeii, and to connect each part of the model to the documents that have been used as sources. The proof of concept also shows how the application of LOD technology can, potentially, change the way 3D visualisation is used in academia, not only making 3D models documented and, therefore, closer to a scientific publication, but, also, encouraging exchange and reuse of data and facilitating preservation. The thesis discusses the rationale behind the creation of the ontology, its application to the documentation of a complex 3D model and its contribution towards a collaborative and transparent use of 3D technologies in academia. The 3D models, the ontology, and the text are equally important components of this work.
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McCreadie, Christopher Andrew. "Widening stakeholder involvement : exploiting interactive 3D visualisation and protocol buffers in geo-computing." Thesis, Abertay University, 2014. https://rke.abertay.ac.uk/en/studentTheses/c26f344f-29d1-4eea-8879-b83862c63143.
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Land use change has an impact on regional sustainability which can be assessed using social, economic and environmental indicators. Stakeholder engagement tools provide a platform that can demonstrate the possible future impacts land use change may have to better inform stakeholder groups of the impact of policy changes or plausible climatic variations. To date some engagement tools are difficult to use or understand and lack user interaction whilst other tools demonstrate model environments with a tightly coupled user interface, resulting in poor performance. The research and development described herein relates to the development and testing of a visualisation engine for rendering the output of an Agent Based Model (ABM) as a 3D Virtual Environment via a loosely-coupled data driven communications protocol called Protocol Buffers. The tool, named Rural Sustainability Visualisation Tool (R.S.V.T) is primarily aimed to enhance nonexpert knowledge and understanding of the effects of land use change, driven by farmer decision making, on the sustainability of a region. Communication protocols are evaluated and Protocol Buffers, a binarybased communications protocol is selected, based on speed of object serialization and data transfer, to pass message from the ABM to the 3D Virtual Environment. Early comparative testing of R.S.V.T and its 2D counterpart RepastS shows R.S.V.T and its loosely-coupled approach offers an increase in performance when rendering land use scenes. The flexibility of Protocol Buffer’s and MongoDB are also shown to have positive performance implications for storing and running of loosely-coupled model simulations. A 3D graphics Application Programming Interface (API), commonly used in the development of computer games technology is selected to develop the Virtual Environment. Multiple visualisation methods, designed to enhance stakeholder engagement and understanding, are developed and tested to determine their suitability in both user preference and information retrieval. The application of a prototype is demonstrated using a case study based in the Lunan catchment in Scotland, which has water quality and biodiversity issues due to intense agriculture. The region is modelled using three scenario storylines that broadly describe plausible futures. Business as Might Be Usual (BAMBU), Growth Applied Strategy (GRAS) and the Sustainable European Development Goal (SEDG) are the applied scenarios. The performance of the tool is assessed and it is found that R.S.V.T can run faster than its 2D equivalent when loosely coupled with a 3D Virtual Environment. The 3D Virtual Environment and its associated visualisation methods are assessed using non-expert stakeholder groups and it is shown that 3D ABM output is generally preferred to 2D ABM output. Insights are also gained into the most appropriate visualisation techniques for agricultural landscapes. Finally, the benefit of taking a loosely-coupled approach to the visualisation of model data is demonstrated through the performance of Protocol Buffers during testing, showing it is capable of transferring large amounts of model data to a bespoke visual front-end.
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Jamin, Clément. "Algorithmes et structures de données compactes pour la visualisation interactive d’objets 3D volumineux." Thesis, Lyon 1, 2009. http://www.theses.fr/2009LYO10133.
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Les méthodes de compression progressives sont désormais arrivées à maturité (les taux de compression sont proches des taux théoriques) et la visualisation interactive de maillages volumineux est devenue une réalité depuis quelques années. Cependant, même si l’association de la compression et de la visualisation est souvent mentionnée comme perspective, très peu d’articles traitent réellement ce problème, et les fichiers créés par les algorithmes de visualisation sont souvent beaucoup plus volumineux que les originaux. En réalité, la compression favorise une taille réduite de fichier au détriment de l’accès rapide aux données, alors que les méthodes de visualisation se concentrent sur la rapidité de rendu : les deux objectifs s’opposent et se font concurrence. A partir d’une méthode de compression progressive existante incompatible avec le raffinement sélectif et interactif, et uniquement utilisable sur des maillages de taille modeste, cette thèse tente de réconcilier compression sans perte et visualisation en proposant de nouveaux algorithmes et structures de données qui réduisent la taille des objets tout en proposant une visualisation rapide et interactive. En plus de cette double capacité, la méthode proposée est out-of-core et peut traiter des maillages de plusieurs centaines de millions de points. Par ailleurs, elle présente l’avantage de traiter tout complexe simplicial de dimension n, des soupes de triangles aux maillages volumiquesProgressive compression methods are now mature (obtained rates are close to theoretical bounds) and interactive visualization of huge meshes has been a reality for a few years. However, even if the combination of compression and visualization is often mentioned as a perspective, very few papers deal with this problem, and the files created by visualization algorithms are often much larger than the original ones. In fact, compression favors a low file size to the detriment of a fast data access, whereas visualization methods focus on rendering speed : both goals are opposing and competing. Starting from an existing progressive compression method incompatible with selective and interactive refinements and usable on small-sized meshes only, this thesis tries to reconcile lossless compression and visualization by proposing new algorithms and data structures which radically reduce the size of the objects while supporting a fast interactive navigation. In addition to this double capability, our method works out-of-core and can handle meshes containing several hundreds of millions vertices. Furthermore, it presents the advantage of dealing with any n-dimensional simplicial complex, which includes triangle soups or volumetric meshes
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Christoph, Heilmair. "GPU-Based Visualisation of Viewshed from Roads or Areas in a 3D Environment." Thesis, Linköpings universitet, Informationskodning, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130699.
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Viewshed refers to the calculation and visualisation of what part of a terrain isvisible from a given observer point. It is used within many fields, such as militaryplanning or telecommunication tower placement. So far, no general fast methodsexist for calculating the viewshed for multiple observers that may for instancerepresent a road within the terrain. Additionally, if the terrain contains over-lapping structures such as man-made constructions like bridges, most currentviewshed algorithms fail. This report describes two novel methods for viewshedcalculation using multiple observers for terrain that may contain overlappingstructures. The methods have been developed at Vricon in Linköping as a Mas-ter’s Thesis project. Both methods are implemented using the graphics program-ming unit and the OpenGL graphics library, using a computer graphics approach.Results are presented in the form of figures and images, as well as running timetables using two different test setups. Lastly, future possible improvements arealso discussed. The results show that the first method is a viable real-time solu-tion and that the second method requires some additional work.
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Jones, Gareth. "Region classification for 3D visualisation : representing static and dynamic properties for medical diagnosis." Thesis, University of Sussex, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262626.
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Dodo, Meva. "Etude de l'apport de la visualisation 3D interactive pour l'administration de systèmes complexe." Toulouse 3, 2008. http://thesesups.ups-tlse.fr/358/.
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Cette thèse propose de nouvelles méthodes qui permettent de faciliter l'analyse et la compréhension de la structure des systèmes complexes ainsi que les différents événements générés par les ressources. Des techniques de représentation 3D sont proposées afin de permettre la visualisation de tout type de structure de systèmes complexes. Notre approche est matérialisée par un nouvel algorithme d'affichage 3D de larges graphes. Cette algorithme est basé sur une nouvelle approche d'optimisation de l'algorithme force-attraction-répulsion (FDP) afin mieux de distribuer les nœuds d'un graphe dans un espace 3D, et nous l'avons associé à des méthodes d'optimisation afin d'améliorer sa performance. La deuxième approche se propose d'associer à la représentation 3D du graphe des mondes 3D qui facilitent l'analyse et l'exploration de la structure du système à étudierThe aim of this thesis is to study new methods which allow to improve the understanding of complex systems' structure and to analyze the various events generated by its resources. Three-dimensional techniques are proposed to easy the analysis of the structure of complex systems. A new algorithm for drawing, in 3D, large graphs is proposed in order to optimize the layout of a complex structure. Our method is based on the optimization of the force-directed placement algorithm (FDP) that allows effectively and aesthetically displaying large graphs. Our second approach is to propose metaphors that allow to easily understand the different events generated by devices. This approach is based on the three attributes that define an event: "what, when, where", and it is associated with filtering techniques that choose interesting events according to the management needs