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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
271

Visualising the Visual Behaviour of Vehicle Drivers / Visualisering av visuellt beteende hos fordonsförare

Blissing, Björn January 2002 (has links)
Most traffic accidents are caused by human factors. The design of the driver environment has proven essential to facilitate safe driving. With the advent of new devices such as mobile telephones, GPS-navigation and similar systems the workload on the driver has been even more complicated. There is an obvious need for tools supporting objective evaluation of such systems, in order to design more effective and simpler driver environments. At the moment video is the most used technique for capturing the drivers visual behaviour. But the analysis of these recordings is very time consuming and only give an estimate of where the visual attention is. An automated tool for analysing visual behaviour would minimize the post processing drastically and leave more time for understanding the data. In this thesis the development of a tool for visualising where the driver’s attention is while driving the vehicle. This includes methods for playing back data stored on a hard drive, but also methods for joining data from multiple different sources.
272

Interface development for environment's monitoring and exploring in the system of RESCUER

Mladenov, Dimitar January 2006 (has links)
This project presents a model of monitoring GUI, built for human search and rescue system, part of RESCUER system. This system is an innovative system with main task decreasing the human involvement in human search and rescue or another type of dangerous missions. In this project we try to make functional and easy to use interface that provide the most necessary information on one screen, such as map of the investigated area, human presence, environment status and status of the most important sensors of the robocar. We also present two already developed interfaces solving similar to ours problem and compare our interface with them and also we present the way of building our GUI on Matlab environment. The final result is an interface, combining the advantages of the other two investigated GUIs and visualises the risk zones, different types of risks that can be expected in the investigated area.
273

Visualisation et interaction pour l’exploration et la perception immersive de données 3D / Interaction and visualization techniques for immersive exploration and perception of 3D datasets

Wang, Nan 17 February 2012 (has links)
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. / The 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.
274

Modélisation moléculaire de matrikines et de protéines matricelles : approches théoriques et évaluations biologiques / Molecular Modelisation of Proteins within the Extracelluar Matrix : Theoretical Approaches and Biological Evaluations

Haschka, Thomas 21 December 2012 (has links)
Ce document traite des aspects différents de la modélisation moléculaire d'une protéine de la matrice extracellulaire. Le domaine de signature des thrombospondines est étudié en détail dans ce document en faisant appel aux champs variés de la science. La complexité de ce domaine nécessite l'utilisation des approches de la mécanique quantique moléculaire en plus de la dynamique moléculaire classique. En reliant les deux approches un nouveau algorithme a été développé afin d'attribuer des charges partielles à partir des résultats obtenus par des méthodes ab-initio. Pour implémenter cet algorithme d'une façon efficace, les nouvelles méthodes de la programmation massivement parallèle ont été utilisées qui nous permettent entre autres de faire tourner cet algorithme sur les procsesseurs graphiques. Nous avons également utilisé et développé des nouvelles méthodes de la visualisation moléculaire rapprochant l'art à la science. En plus, de ces développements nous avons obtenus des résultats intéressants sur la dynamique du domaine de signature. Nous avons pu identifier les ions échangeables de ce domaine. Nous avons vérifié et élargie les modèles existants de la thrombospondine dans des concentrations faibles de calcium. En utilisant la dynamique moléculaire nous avons également évalué des sites importants de fixations pour le développement de nouveaux médicaments contre le cancer. / This document deals with the various aspects of molecular modeling of a protein in the extracellular matrix. In this work the thrombospondin signature domain is studied in detail, using various methods from different fields of science. Due to the complexity of the protein, a classical molecular dynamics and a quantum molecular approach is chosen to gain insights into the thrombospondin signature domain. During this process a new algorithm that allows to derive partial charges from ab-initio calculations has been developed. In order to run this algorithm in an efficient way new programming techniques, such as massive multiparallel programming on graphics processors has been used. Further new visualization methods have been either tried or developed effectively generating a new kind of art from the scientific results that have been obtained in this project. Besides these developments several interesting insights into the dynamics of thrombospondins have been revealed. We were able to identify the exchangeable ions within the thrombospondin signature domain, and were further capable to verify and extend existing models for a low calcium signature domain structure. Binding sites important for cancer drug design have also been evaluated using the molecular dynamics simulations.
275

Waveform Visualisation And Plot Optimization

Hammarstedt, Emil January 2009 (has links)
This thesis is focused on the improvement of an existing implementation of a waveform visualizer. The problem area handled in this work has its focus on how to reduce the number of points to be plotted. The given waveform visualizer was extended by the use of two additional algorithms. First, a Level Of Detail (LOD) algorithm that gives the subset of points that are necessary to plot the waveform in the current zoom level. Second, a straight line identification algorithm to find a series of points aligned in a straight line, only leaving the end points and then drawing a line between them. These two optimizations are the main focus of this work.Additionally, an exporting functionality was implemented to export the plot data into several different data formats. Also some improvements of zooming, panning, some GUI design, and a new drag and drop functionality was constructed.
276

Kan 3D-visualisering hjälpa till vid artbestämning?

Hanson, Maria January 2008 (has links)
ABSTRACT Syftet med mitt examensarbete är att forska i om bilder genererade ur 3D-modeller är en effektiv illustreringsmetod vid artbestämning. Arbetet består av två delar, en praktisk och en teoretisk. Den praktiska delen av arbetet ska resultera i renderade bilder av en mångfoting sedd utifrån olika vinklar och avstånd. Detaljrikedom och manér ska vara fotorealistiska. Den teoretiska delen ska ta upp fördelar och nackdelar med 3D som bildteknik vid artbestämning. Jag ska även redogöra för de vanligaste bildteknikerna, som används vid naturvetenskaplig illustration samt kortfattat berätta om nya tekniker. En av de största fördelarna med att använda sig av 3D-visualisering vid artbestämning är om man arbetar med snarlika arter. Att generera bilder ur 3D-modeller kan vara en effektiv metod därför att man kan utgå ifrån en och samma grundmodell när man modellerar olika arter och endast göra förändringar där det behövs. Andra fördelar är att det går att vrida och böja på en grundmodell samt att man kan få ut renderingar av ett objekt i många olika vinklar och från olika avstånd. På så vis går det att använda sig av en och samma grundmodell när man jobbar med snarlika arter och ändå få ut varierade bilder i slutändan.
277

Analysis of the chemical space of antimalarial compounds by generative topographie mapping / Analyse de l'espace chimique des composés antipaludiques par la méthode GTM

Sidorov, Pavel 25 September 2017 (has links)
Cette thèse est consacrée à l’analyse de l’espace chimique des composés antipaludiques. L’analyse est faite à l’aide de la méthode des cartes topographiques génératrices (GTM). Un nouveau concept des cartes universelles est introduit et discuté en détail dans cette thèse : ce sont des cartes qui sont capables d’accommoder plusieurs jeux de données et les propriétés associées simultanément. Trois types des cartes sont construits et analysés : les cartes locales, globales et universelles. Elles sont toutes compétentes à la prédiction des composés actifs contre le parasite, ainsi qu’à l’analyse de l’espace chimique. Elles nous permettent d’étudier le recouvrement des données issues des sources différentes, de détecter des terra incognita de l’espace chimique, identifier des zones correspondantes aux différents mécanismes d’action, et révéler des incohérences d’annotations des données. / This thesis is dedicated to the concept of the analysis of chemical space, and the application of thatconcept to antimalarial compounds. The analysis of the chemical space of antimalarial compoundshere is done with the aid of the Generative Topographic Mapping (GTM) method. A concept ofUniversal GTM maps is developed and discussed in detail in this thesis: these are maps that areable to accommodate different datasets and associated properties. Three types of maps are builtand analyzed: local, global, and universal. All these maps perform well in predicting compoundsactive against the parasite, as well as in the analysis of chemical space: they help us to study theoverlap of data coming from different sources, detect terra incognita of the antimalarial space,delineate zones corresponding to various mechanisms of action, as well as highlight theinconsistencies in data annotations.
278

Graphicacy and the third dimension: an investigation into the problem of poor performance in relief mapwork in South African secondary schools

Burton, Michael St. John Whitehead January 1986 (has links)
Three-dimensional graphicacy is the part of map work that appears to be the most problematIcal. Bartz (1970) says that thinking and visualising in three-dimensional space is difficult enough, but trying to derive notions in three-dimensions, when you have only seen them as they are represented in distorted two-dimensional fashion, is even more difficult. Yet pupils of geography are required to learn such three-dimensional concepts from the two-dimensional distorted map presentations. The geography teacher has an important educational role to play in promoting graphicacy and Balchin (1965), who coined the term, felt that it should be an essential underpinning of an integrated education. The problem is that children perform badly, teachers are not successfully imparting three-dimensional graphicacy skills and as Board and Taylor (1977) indicate, for some time now it has been fashionable to dismiss maps as being irrelevant or useless in geographical research. This thesis attempts to analyse this reported malady, the problems are exposed and solutions offered. Investigation of the literature, with the aim of clarifying the problems involved, follows four leads. These are the part played by the map as a mode of communication, the physical processes involved in mapwork revealed by work in the realm of neurophysiology, the process of visualisation in the field of perception and psychology, and finally the stage of conceptual development of the mapworker. The state of affairs in South Africa is disclosed by an analysis of teacher-directed literature, of examination syllabuses, of text-book treatment of three-dimensional mapwork in South Africa and overseas, of past examination questions, and finally of teachers' views. Experimental exercises have been executed in an attempt to link the key findings of published research to the local scene. Conclusions are then drawn, and recommendations made for improving three-dimensional graphicacy in South African secondary schools.
279

HBTQ-historia i arkiv : Var finns den och hur ser den ut? / LGBTQ-history in archives : Where can we find it and what does it look like?

Rune, Matilda January 2017 (has links)
The aim of this study is to examine how the history about LGBTQ-people is represented in archives, focusing on the websites, social media and projects of the archives. The study revolves around three themes, identity, accessibility and participation and seeks to examine how four selected archives work to highlight, gather and inform about the history, experiences and lives of the LGBTQ-community represented in their collections.  The study is based on the theoretical framework of the connection between archives and identity and the problem of silence in archives where marginalised groups are not heard, and therefore seeks to examine how archives can work towards breaking the silence. The search process consists of a netographic survey and is analysed and then discussed in a broader perspective using the three themes and the theoretical frameworks. Conclusions of the study shows that the chosen archives, depending on their respective starting points, skills and resuscitations, work in ways that together could form a basis for better understanding of how to create and highlight LGBTQ-history. There are e.g difficulties today in searching for documents about LGBTQ-history in traditional archives, due to the need to revise the subject words to create more accessibility. This is something traditional archives can learn from the more progressive LGBTQ-focused archives. This is a two years master’s thesis in Archival Science.
280

Visualisation d'information : de la théorie sémiotique à des exemples pratiques basés sur la représentation de graphes et d'hypergraphes / Information visualization : from semiotic theory to practical examples based on graphs and hypergraphs representation

Sallaberry, Arnaud 18 October 2011 (has links)
La visualisation d'information est une discipline récente en pleine expansion et qui a pour objet l'étude des méthodes de représentation visuelle de données abstraites, c'est-à-dire non géolocalisées. La sémiotique est quant à elle une discipline beaucoup plus ancienne (fin du XIXième siècle) qui s'intéresse aux divers systèmes de signes nécessaires aux processusde communication. A ce jour, peu de travaux ont été réalisés pour mettre en parallèle ces deux disciplines. C'est pourquoi le premier chapitre de cette thèse est dédié à l'étude de la visualisation d'information selon les paradigmes élaborés par son ainée tout au long du XXième siècle. Nous montrons en particulier comment l'un des modèles les plus aboutis de validation de visualisations (modèle imbriqué de Tamara Munzner) correspond au processus d'étude sémiotique d'énoncés. Le second chapitre est consacré à la visualisation de graphe, outil de modélisation puissant de divers ensembles de données abstraites. Nous proposons d'une part une application permettant de visualiser et de naviguer à travers les pages Internet retournées par un moteur de recherche et d'autre part un algorithme de visualisation de hiérarchies dynamiques sous forme de "cartes géographiques". Enfin, nous évoquons dans le troisième chapitre un autre outil de modélisation de donnéesabstraites : les hypergraphes. Nous proposons des résultats théoriques concernant leur représentation et donnons une ébauche de solution permettant de les visualiser. / Information visualization aims at designing visual representations of abstract data, furthermore relying on interaction as a mean to discover knowledge. The first part of this thesis challenges Information Visualization by drawing a parallel with semiotics, a 19th century research field focusing on systems of signs required for communication. We develop a point of view on Information Visualization based on the paradigms developed by semioticians during the 20th century. In particular, we show how the visualization validation model proposed by Tamara Munzner is related to the process used by semioticians for utterance analysis. The second part of the thesis focuses on graph visualization and describes two techniques and system prototypes targeting specific application domains. The first one is an interactive technique to visualize and navigate through Web search results. The second one is an algorithm for the visualization of dynamic hierarchies exploiting the analogy with “geographical maps”. Finally, the third chapter is devoted to another model used to structure abstract data : hypergraphs. We propose theoretical results on hypergraph drawing and a preliminary technique to visualize hypergraphs.

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