• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 267
  • 261
  • 115
  • 64
  • 39
  • 25
  • 23
  • 6
  • 5
  • 5
  • 5
  • 4
  • 3
  • 1
  • 1
  • Tagged with
  • 920
  • 156
  • 105
  • 103
  • 98
  • 95
  • 68
  • 59
  • 53
  • 53
  • 50
  • 48
  • 46
  • 43
  • 43
  • 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.
331

Terénní čtyřkolový motocykl pro seniory / Off-road four-wheel motorcycle for seniors

Mihálik, Boris January 2014 (has links)
This diploma thesis deals with the design and realization of function pattern of off-road four-wheel vehicle for seniors. First part of the work consist of research of current commercial vehicles for the elderly, as well as small four-wheeled off-road vehicles and their individual design elements. In this part of the work were also dismantled the proposed legislation allowing legal movement of vehicles on public roads and seniors ergonomics. Another section dealt with the proposal of possible variants for solving the essential structural elements of the vehicle. The last major parts of the work deals with detail description of each selected construction elements of the vehicle. Functional pattern has been manufactured and tested. At the end of this work were published the results of testing of the vehicle and also were proposed possible changes of design.
332

Výletní místa / Picknick places

Fialová, Eliška January 2013 (has links)
I paint parks- places for trips, the terrains and spaces. I depict its structure, which is composed from various elements. I am interested in humane touch and movement and especially in their look. I am interested in the by human kind build environment or moved places. Moreover hove it influence humane being. Parks are places created for touch, for extraordinary feelings, for fulfill perceptions. Nevertheless I try to describe that sort of places and recreate them in my paintings.
333

Interaktivní editor 3D terénu / Interactive 3D Terrain Editor

Synáček, Jan January 2011 (has links)
The subject matter of this work is a concept of an interactive 3D terrain editor. Its basic functionality, graphical user interface and possible extensions are defined. There are a lot of existing terrain editing tools, therefore presentation of some existing systems capable of editing and generating computer terrain is also included. The editor is implemented and it is capable of performing simple editing, such as raising, lowering or levelling the terrain. Graphical user interface is also a part of the implementation. The editor allows inserting 3D models into the scene so it was easier to represent some objects displayed only in the texture in 3D space. Models can be edited using some simple transformations. Performance tests are undertaken and possibilities of extending the program discussed.
334

Caractériser et détecter les communautés dans les réseaux sociaux / Characterising and detecting communities in social networks

Creusefond, Jean 21 February 2017 (has links)
Dans cette thèse, je commence par présenter une nouvelle caractérisation des communautés à partir d'un réseau de messages inscrits dans le temps. Je montre que la structure de ce réseau a un lien avec les communautés : on trouve majoritairement des échanges d'information à l'intérieur des communautés tandis que les frontières servent à la diffusion.Je propose ensuite d'évaluer les communautés par la vitesse de propagation des communications qui s'y déroulent avec une nouvelle fonction de qualité : la compacité. J'y présente aussi un algorithme de détection de communautés, le Lex-Clustering, basé sur un algorithme de parcours de graphe qui reproduit des caractéristiques des modèles de diffusion d'information. Enfin, je présente une méthodologie permettant de faire le lien entre les fonctions de qualité et les vérités de terrain. J'introduis le concept de contexte, des ensembles de vérités de terrain qui présentente des ressemblances. Je mets à disposition un logiciel nommé CoDACom (Community Detection Algorithm Comparator, codacom.greyc.fr) permettant d'appliquer cette méthodologie ainsi que d'utiliser un grand nombre d'outils de détection de communautés. / N this thesis, I first present a new way of characterising communities from a network of timestamped messages. I show that its structure is linked with communities : communication structures are over-represented inside communities while diffusion structures appear mainly on the boundaries.Then, I propose to evaluate communities with a new quality function, compacity, that measures the propagation speed of communications in communities. I also present the Lex-Clustering, a new community detection algorithm based on the LexDFS graph traversal that features some characteristics of information diffusion.Finally, I present a methodology that I used to link quality functions and ground-truths. I introduce the concept of contexts, sets of ground-truths that are similar in some way. I implemented this methodology in a software called CoDACom (Community Detection Algorithm Comparator, codacom.greyc.fr) that also provides many community detection tools.
335

Detekce linií terénní kostry z dat leteckého laserového skenování / Detection of Terrain Skeleton Lines based on Laser Scanning Data

Jaroš, Jakub January 2011 (has links)
The objective of the thesis is to design a new detection method of terrain skeleton lines from airborne laser scanning data. The theoretical part provides a brief introduction to airborne laser scanning issue. There are presented major principles of the technology and procedures applied to create digital terrain model from laser data. There is also described an application of airborne laser scanning in the area of the Czech Republic in detail and follows an exact specification of key terms of the thesis. From the geomorphology, topography and geoinformatics point of view there are defined especially terms like terrain skeleton lines, breakline, valley and ridge. Literary research consists of the summary of already published method of breakline detection. There are algorithms focused on data processing in form of original point cloud as well as algorithms focused on processing data in the raster form. Primary goal of the theoretical part is to express major principles of already published method of detection. The practical part firstly introduces data that are used further in the thesis. The objective of the thesis is a description of a new method of detection of terrain skeleton lines. The method processes laser data converted into raster form and it is based on the analysis of transverse elevation profile...
336

Rivers, Mountains, and Everything in Between: How Terrain Affects Interstate Territorial Disputes

Burggren, Tyler Matthew Goodman 05 1900 (has links)
Geography has been a central element in shaping conflict through the ages, and is especially important in determining which states fight, why they fight, when they fight, and more importantly, where they fight. Despite this, conflict literature has primarily focused on human geography while largely ignoring the geospatial context of ‘where' conflict occurs, or crucially, doesn't occur. Territorial disputes are highly salient issues that quite often result in militarized disputes. Terrain has been key to mitigating conflict even in the face of major variance in state capability and power projection. In this study I investigate how terrain characteristics interact with power projection, opportunity, and willingness and the impact this has across territorial disputes. Exploring terrain's interaction with these concepts and its effect among different types of conflict furthers our understanding of the questions listed above.
337

Improving Ground Penetrating Radar Resolution of Features of Active Sinkholes

Gooch, Bradley Tyler 12 March 2010 (has links)
Ground penetrating radar (GPR) is widely used to identify locations of sinkholes in covered karst terrain in Florida. Some sinkholes serve as hydraulic conduits between the surficial and underlying aquifers. Their role is critical in determining the surficial aquifer response to pumping in deeper aquifers. Improved methods for discriminating between hydraulically active sinkholes and plugged sinkholes could help regional water management. In the covered karst of west-central Florida a clay-rich weathering horizon forms over the limestone. The clay-rich layer is in turn overlain by surficial sands. Ground penetrating radar profiles typically show a strong reflector from the top of clay-rich horizon as well as internal layering within sands. Active sinkholes are expected to have sandy conduits that broach the clay layer, and perhaps layering in the overlying sand indicative of ongoing subsidence. Three dimensional simulations of GPR profiles over sinkhole with and without conduits were run with the finite-difference time-domain (FDTD) program GPRMAX. Results from the synthetic surveys were then processed with standard techniques, including migration. The modeling confirms that conduits appear in GPR records primarily as gaps in the return from the clay layer. The modeling also shows that non-traditional survey geometries (varying antenna spacing and orientation) are unlikely to recover more information than traditional proximal transmitter-receiver separation. Also examined are GPR profiles and 3D grids over a set of active and inactive sinkholes in Tampa, Florida. Results from these surveys showed decent structural recovery of a small sinkhole similar in structure to that of the modeled ones. Indications of active subsidence and possible conduit structure were apparent from this data. Finally, the dense surveys served as a benchmark to compare interpretations taken with the same surveys at lower spatial resolutions and profiles with 2D-only processing methods in order to understand errors in analysis and interpretation that are possible from 2D surveys. Two-dimensional surveys, 2D processed and migrated, showed some similarity to the 3D results previously mentioned but contained more complexities and artifacts, which led to poorer interpretation ability.
338

Contribuer à la prévention des risques d'origine géologique :l'évaluation de la vulnérabilité des populations dans un contexte de rareté de données. Les cas de Goma et Bukavu (RDCongo)

Michellier, Caroline 13 September 2017 (has links) (PDF)
En République Démocratique du Congo (RDC), les provinces densément peuplées du Nord et du Sud-Kivu sont exposées à plusieurs types d’aléas d’origine géologique, tels que les glissements de terrain et les éruptions volcaniques des volcans Nyiragongo et Nyamulagira. En outre, la région souffre d'un faible niveau économique et de conflits récurrents qui contribuent à affaiblir encore davantage la population menacée.Cette recherche doctorale a été réalisée dans le cadre du projet GeoRisCA (Belspo, programme SSD, SD/RI/02A ;http://georisca.africamuseum.be), dont l'objectif global répond à la nécessité d'étudier les risques d’origine géologique dans la région du lac Kivu, afin de contribuer à la prévention des risques, à l’échelle régionale et locale. Cette recherche tente spécifiquement de répondre à la question de l’évaluation de la vulnérabilité d'une population confrontée à des aléas d’origine géologique, dans un contexte de rareté de données.L'étude a été menée dans deux sites urbains :Bukavu, chef-lieu de la province du Sud-Kivu qui compte environ 870.000 habitants, une ville affectée par des mouvements de terrain fréquents, et Goma, chef-lieu de la province du Nord-Kivu où vivent environ 775.000 personnes sous la menace des coulées de lave du volcan Nyiragongo dont la dernière éruption date de 2002. Pour combler le manque de données socio-démographiques fiables, une méthodologie adaptée à ce contexte particulier et s'appuyant sur la télédétection combinée à des enquêtes quantitatives, des entretiens approfondis et une connaissance détaillée de la zone étudiée a été développée. Deux bases de données démographiques comprenant des variables individuelles et de ménages ont été construites - une pour chaque ville étudiée. Ces données ont constitué la base de la réalisation de cartes détaillées de densité de population et ont permis l’analyse spatiale des caractéristiques socio-économiques des deux zones urbaines. Un indice de vulnérabilité sociale a ensuite été élaboré à partir de l’analyse en composantes principales (ACP) d’un large éventail de ces données socio-économiques. Un indice de vulnérabilité dit « opérationnel » a ensuite été déduit de l’indice de vulnérabilité sociale, afin de refléter davantage le contexte local et faciliter la reproductibilité du travail de terrain. La dernière étape de notre étude consistait à combiner spatialement l’évaluation de la vulnérabilité et la densité de la population aux analyses de susceptibilité aux glissements de terrain et de probabilité d’invasion des coulées de lave développées par des experts dans le cadre du projet GeoRisCA. Les cartes de risques obtenues constituent de nouveaux outils d'aide à la décision ;elles ont été transmises aux autorités locales et permettent d’une part le renforcement des politiques de réduction des risques de catastrophes et des programmes de prévention des catastrophes, et d’autre part une nouvelle approche de l’aménagement du territoire. Enfin, il est important de souligner que cette recherche n’aurait pu être réalisée sans un étroit partenariat avec les institutions scientifiques et les autorités locales, et a significativement contribué à améliorer les interactions entre ces différentes parties prenantes. / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
339

Förluster och stridsavstånd vid övningar för SIB

Olin, Max January 2020 (has links)
The significance of urban areas for military operations is increasing due to the proliferation of cities and the amount of people living in them; armed forces must, to a higher degree, fight in these urban areas in the future. This essay highlights that, despite the increasing importance of urban areas for armed forces, there is a lack of developed theory regarding how armed forces fight in urban areas and how tactics, techniques, and procedures result in casualties. Using previous research on urban warfare, this essay posits three hypotheses and applies these on exercises from the Swedish Armed Forces’ training area for military operations in urban terrain.        The results show that mortars are responsible for a large number of the casualties incurred during the exercises. When exercises involve vehicles the combat ranges, at which casualties are suffered, are longer in comparison to exercises without vehicles. A small percentage of casualties are suffered in close-quarters combat. Finally, the essay elaborates on the meaning of the results and offer some possible explanations that also are suitable for further research. It concludes that further research is warranted, especially regarding close-quarters combat and the use of hand grenades.
340

Run-time Terrain Deformation in Unreal Engine 4

Magnom, Rikard January 2020 (has links)
Background. When developing video games, an often desired trait is that of player immersion. Player immersion can be achieved through many different ways. However, a common technique used is to allow the player to affect the environment in some way, through destruction or deformation. Unreal Engine 4 is a commonly used commercial game engine, that lacks features necessary to deform terrain at run-time. Objectives. This thesis explores the viability of run-time performant terrain deformation in Unreal Engine version 4.23. A deformation technique of a depth-based Dynamically-Displaced Height Map (DDHM) is selected for implementation and tested with various sizes of landscape terrains. Methods. A small literature study is performed to select a feasible run-time terrain deformation technique. The technique is then implemented in the engine, along with modifications to the engine to provide the necessary functionality. The implementation is then tested on performance and accuracy. Results. The DDHM technique is shown to provide run-time performant terrain deformation for smaller terrain sizes, consisting of an individual landscape component. The selected technique does not meet the run-time requirements for full, large-scale deformation. Conclusions. Run-time performant terrain deformation is shown to be achievable in Unreal Engine 4.23. While the selected technique fails to achieve satisfying results for larger terrain sizes, results on individual landscape components show feasibility for generic technique implementations. / Bakgrund. Under utvecklingen av datorspel är det ofta en eftertraktad egenskap att kunna övertyga spelaren om realismen i spelvärlden. Detta kan uppnås på flera sätt, men en vanlig teknik är att låta spela påverka omgivningen i spelet på något sätt, genom förstörelse eller deformering. Unreal Engine 4 är en vida använd kommersiell spelmotor som saknar funktionalitet för att deformera terräng i realtid. Syfte. Syftet med detta arbete är att utforska genomförbarheten i att tillföra terrängdeformering i realtid i Unreal Engine version 4.23. En deformeringsteknik involverande en Dynamically-Displaced Height Map (DDHM) väljs ut för implementation och testas med olika storlekar på landskapsterräng. Metod. En mindre litteraturstudie genomförs för att välja en rimlig teknik för terrängdeformering i körtid. Tekniken implementeras sedan i motorn, i sambard med modifikationer till motorn för att tillföra nödvändig funktionalitet. Implementationen testas sedan på prestanda och precision. Resultat. DDHM-tekniken visas kunna tillföra körtidsduglig terrängdeformering för mindre terrängstorlekar, bestående av individuella landskapskomponenter. Tekniken möter inte realtidskriterierna för full, storskalig terrängdeformation. Slutsatser. Deformering av terräng i körtid visas vara genomförbart i Unreal Engine 4.23. Den utvalda tekniken visar lovande resultat för mindre storlekar av landskapsterräng, men misslyckas att prestera för större terrängstorlekar.

Page generated in 0.0451 seconds