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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.
41

Studying Window Energy Performance Using Thermal Camera

Akbari, Sevda January 2020 (has links)
Windows, which are responsible for 45% of overall heat loss, play a major role in a building’s energy performance. Therefore, it is critical to measure window energy performance for existing buildings. This study aimed to evaluate the energy performance of windows to determine if replacement of windows is necessary. The evaluation was based on window location, height, orientation, and weather condition in a high-rise residential building. A thermal camera was used for measurements and statistical analyses were performed for measured data. Analysis results showed different performance of each side and floor of the building with a significant difference at the 0.05 level due to various temperatures, wind speeds, and directions. This study suggests using more efficient windows on upper floors, particularly from the fourth floor and above is beneficial as well as considering dominant wind speed and direction for the best configuration of window design.
42

[en] AUTOMATIC CAMERA CONTROL IN VIRTUAL DYNAMIC ENVIRONMENTS / [pt] CONTROLE AUTOMÁTICO DE CÂMERA EM AMBIENTES VIRTUAIS DINÂMICOS

RODRIGO DE PROENCA GOMES HERMANN 03 January 2006 (has links)
[pt] Com o avanço do poder de processamento gráfico e a popularização dos jogos eletrônicos, começam a surgir novas formas de entretenimento, entre elas a de espectadores de jogos. Os requisitos para o posicionamento de câmera para os espectadores visualizarem os jogos são diferentes dos aplicados aos jogadores. Enquanto a câmera para os jogadores deve atender a requisitos de jogabilidade, a câmera para os espectadores deve explorar diferentes ângulos de visualização a fim de aumentar a imersão no ambiente dos jogos e explorar a emoção das cenas. O cinema já evoluiu toda uma linguagem cinematográfica que potencializa a interpretação de cenas. Pesquisas recentes procuram usar a cinematografia na visualização de jogos. O principal desafio na adaptação da cinematografia para os jogos reside na existência de um ambiente dinâmico, onde não se pode prever o andamento da história. Podemos identificar três módulos para a adaptação da cinematografia em jogos: roteirista, responsável por identificar o que está ocorrendo na cena; diretor/editor, responsável por definir as melhores tomadas para capturar a cena; cinegrafista, responsável por posicionar a câmera no ambiente dinâmico para melhor atender às demandas do módulo diretor/editor. Este trabalho propõe a implementação de um módulo cinegrafista. A partir de requisitos para o posicionamento da câmera oriundos de um módulo externo, propõe-se um modelo de câmera que faz o posicionamento automático da câmera. Os requisitos de posicionamento são expressos em um conjunto de restrições que devem ser atendidas pelo modelo de câmera. A câmera usa um modelo físico baseado em um sistema de partículas regido pelo método de Verlet, empregando o método de relaxação para a convergência do sistema a fim de atender às restrições impostas. Experimentos computacionais demonstram a capacidade do módulo proposto de atender a sofisticadas regras de posicionamento de câmera, baseando-se em composições de restrições simples. Princípios da cinematografia, como enquadramento, posicionamento e movimento de câmeras, e respeito à linha de ação, são facilmente respeitados pelo módulo proposto. / [en] With the evolution in graphics processing power and the popularization of electronic games, new forms of entertainment, such as being a game spectator. The requirements for positioning the camera for the spectators to view the games are different from those applied to players. The camera for the players must fulfill playability requirements, while the camera for the spectators must explore different viewing angles in order to increase the immersion in the game environment and to explore the thrill of the scenes. The cinema has evolved a whole cinematographic language that optimizes the scene interpretation. Recent research has been seeking to apply cinematography to game visualization. The main challenge in the adaptation of the cinematographic language for games lies in the existence of a dynamic environment in which the story`s progress cannot be anticipated. Three modules can be identified to adopt the cinematographic language in games: screenwriter, responsible for identifying what is happening in the scene; director/editor, responsible for defining the best takes to capture the scene; and cinematographer, responsible for positioning the camera in the dynamic environment to better comply with the director/editor`s demands. The present work proposes the implementation of a cinematographer module. Based on camera position requirements obtained from an external module, we propose a camera model that automatically positions the camera. The positioning requirements are expressed by a set of constraints that must be respected by the camera model. The camera uses a physical model based on a particle system oriented by Verlet`s method, and employs the relaxation method to obtain the system`s convergence in order to comply with imposed constraints. Computational experiments have demonstrated the capacity of the proposed module to comply with sophisticated camera positioning rules based on compositions of simple constraints. Cinematography principles such as framing, camera position and movement, and respecting the line of action are easily accomplished by the proposed module.
43

Parameter Extraction And Image Enhancement For Catadioptric Omnidirectional Cameras

Bastanlar, Yalin 01 April 2005 (has links) (PDF)
In this thesis, catadioptric omnidirectional imaging systems are analyzed in detail. Omnidirectional image (ODI) formation characteristics of different camera-mirror configurations are examined and geometrical relations for panoramic and perspective image generation with common mirror types are summarized. A method is developed to determine the unknown parameters of a hyperboloidal-mirrored system using the world coordinates of a set of points and their corresponding image points on the ODI. A linear relation between the parameters of the hyperboloidal mirror is determined as well. Conducted research and findings are instrumental for calibration of such imaging systems. The resolution problem due to the up-sampling while transferring the pixels from ODI to the panoramic image is defined. Enhancing effects of standard interpolation methods on the panoramic images are analyzed and edge detection-based techniques are developed for improving the resolutional quality of the panoramic images. Also, the projection surface alternatives of generating panoramic images are evaluated.
44

Spatial measurement with consumer grade digital cameras

Wackrow, Rene January 2008 (has links)
No description available.
45

Combined Visible and Infrared Video for Use in Wilderness Search and Rescue

Rasmussen, Nathan D. 20 March 2009 (has links) (PDF)
Mini Unmanned Aerial Vehicles (mUAVs) have the potential to be a great asset to Wilderness Search and Rescue groups by providing a bird's eye view of the search area. These vehicles can carry a variety of sensors to better understand the world below. This paper proposes using both Infrared (IR) and Visible Spectrum cameras on a mUAV for Wilderness Search and Rescue. It details a method for combining the color and heat information from these two cameras into a single fused display to reduce needed screen space for remote field use. To align the video frames for fusion, a method for simultaneously pre-calibrating the intrinsic and extrinsic parameters of the cameras and their mount using a single multi-spectral calibration rig is also presented. A user study conducted to validate the proposed image fusion methods showed no reduction in performance when detecting objects of interest in the single-screen fused display compared to a side-by-side display. Furthermore, the users' increased performance on a simultaneous auditory task showed that increased performance on a simultaneous auditory task showed that their cognitive load was reduced when using the fused display.
46

Vision Based Control of Autonomous UAV

Gottleben, Emil January 2016 (has links)
This master thesis investigates the problem of making an unmanned aerial vehicle(uav) follow a person or a group of persons while keeping a fixed distance tothe chosen target. The purpose of this thesis is to give a proof of concept prototypeof how such a system would work to achieve that task. The main problemconsists of controlling the uav based on visual input from a camera. With thehelp of a visual object detection and tracking system, the image coordinates ofthe targets can be found. An algorithm was developed to calculate the target’sworld position based on its image coordinates and the world position and orientationof the uav. A control system was implemented that uses that uses thepositional information to set the velocity of the uav, if its position needs to bechanged. Several strategies for handling groups of targets were investigated. Inaddition a simulator was developed that can be used to simulate the image coordinatesof a target when the world position of the target is known. The systemwas tested during live flights, using a high precision motion capture system forreference. The results were mainly positive in showing proof of concept and evenshowing a relatively high level of precision.
47

Neural networks for computer aided diagnosis of pulmonary images in nuclear medicine

Livieratos-Petratos, George N. January 1995 (has links)
No description available.
48

Analysis of dynamic radionuclide studies using principal components factor analysis

Nijran, Kuldip Singh January 1984 (has links)
No description available.
49

Real-time data compression for machine vision measurement systems

Arshad, Norhashim Mohd January 1998 (has links)
No description available.
50

Jacques : Your underwater camera companion

Edlund, Martin January 2014 (has links)
300 million pictures are uploaded everyday on Facebook alone. We live in a society where photography, filming and self-documentation are a natural part of our lives. But how does it inflict on our experiences when we always are considering camera angles, filters and compositions? We might very well ruin the experiences we so badly want to save. Scuba diving is a special experience. We enter a world with another space of movement, surroundings and animal life. An experience that can only be experienced for a limited time. An adventure one want to remember, save and share. But what implications does it have on ones experience if one also have to focus on documenting it? JACQUES is a product that enables the diver´s to document their dive as a memory to re-experience later and share with others while still leaving them fully immersed in their diving experience. With relatively simple technology such as sonar and video object recognition Jacques can film the diver´s underwater adventure and adept to their behavior without the diver even noticing it. And by being focused on the actual dive one also becomes a better and safer diver.

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