Masters Degrees (Computer Science and Informatics)

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Browsing Masters Degrees (Computer Science and Informatics) by Subject "Computer graphics"

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    3D visualization of data from groundwater flow and transport models
    (University of the Free State, 2000-11) Bekker, Meintjes; Messerschmidt, H. J.; Chiang, W. H.
    English: Groundwater flow and transport models produce large amounts of data, which the human brain cannot possibly grasp. Taking advantage of the natural abilities of the human vision system, 3D visualization is often the tool of choice for understanding and communicating conceptual models, verifying model input, understanding model output, explaining and communicating conclusions and recommendations, and motivating expenses. A 3D visualization tool has therefore been developed for intelligence amplification of model data. The tool is based on a groundwater modeling system (Processing MODFLOW) and makes use of the results from existing groundwater flow (MODFLOW) and transport models (MT3DMS, PHT3D and RT3D.). The Visualization Toolkit (vtk), a C++ class library for visualization was used to render 3D geohydrological objects. Realistic scenes of 3D geospatial models and 3D distributions of geohydrological properties, such as hydraulic conductivity, heads and solute concentrations, can be rendered. The advantages of 3D visualization are evident by applying the visualization tool to case studies.
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    Graphical processing unit assisted image processing for accelerated eye tracking
    (University of the Free State, 2015-02) Du Plessis, Jean-Pierre Louis; Blignaut, P. J.
    English: Eye tracking is a well-established tool utilised in research areas such as neuroscience, psychology and marketing. There are currently many different types of eye trackers available, the most common being video-based remote eye trackers. Many of the currently available remote eye trackers are either expensive, or provide a relatively low sampling frequency. The goal of this dissertation is to present researchers with the option of an affordable high-speed eye tracker. The eye tracker implementation presented in this dissertation was developed to address the lack of low-cost high-speed eye trackers currently available. Traditionally, low-cost systems make use of commercial off-the-shelf components. However, the high frequency at which the developed system runs prohibits the use of such hardware. Instead, affordability of the eye tracker has been evaluated relative to existing commercial systems. To facilitate these high frequencies, the eye tracker developed in this dissertation utilised the Graphical Processing Unit, Microsoft DirectX and HLSL in an attempt to accelerate eye tracking tasks – specifically the processing of the eye video. The final system was evaluated through experimentation to determine its performance in terms of accuracy, precision, trackability and sampling frequency. Through an experiment involving 31 participants, it was demonstrated that the developed solution is capable of sampling at frequencies of 200 Hz and higher, while allowing for head movements within an area of 10×6×10 cm. Furthermore, the system reports a pooled variance precision of approximately 0.3° and an accuracy of around 1° of visual angle for human participants. The entire system can be built for less than 700 euros, and will run on a mid-range computer system. Through the study an alternative is presented for more accessible research in numerous application fields.