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1

Siwela, Blessing. "Web-based management of time-series raster data." Master's thesis, University of Cape Town, 2010. http://hdl.handle.net/11427/6441.

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Data discovery and data handling often presents serious challenges to organizations that manage huge archives of raster datasets such as those generated by satellite remote sensing. Satellite remote sensing produces a regular stream of raster datasets used in many applications including environmental and agricultural monitoring. This thesis presents a system architecture for the management of time-series GIS raster datasets. The architecture is then applied in a prototype implementation for a department that uses remote sensing data for agricultural monitoring. The architecture centres on three key components. The first is a metadatabase to hold metadata for the raster datasets, and an interface to manage the metadatabase and facilitate the search and discovery of raster metadata. The design of the metadatabase involved the examination of existing standards for geographic raster metadata and the determination of the metadata elements required for time-series raster data. The second component is an interactive tool for viewing the time-series raster data discovered via the metadatabase. The third component provides basic image analysis functionality typically required by users of time-series raster datasets. A prototype was implemented using open source software and following the Open Geospatial Consortium specifications for web map services (WMS) version 1.3.0. After implementation, an evaluation of the prototype was carried out by the target users from the RRSU (Regional Remote Sensing Unit) to assess the usability, the added value of the prototype and its impact on the work of the users. The evaluation showed that the prototype system was generally well received, since it allowed both the data managers and users of time-series datasets to save significant amounts of time in their work routines and it also offered some raster data analyses that are useful to a wider community of time-series raster data managers.
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2

Koehler, Richard Bruce. "Raster-based analysis and visualization of hydrologic time-series." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/280516.

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Annual, seasonal, and daily discharge patterns determine many of the physical and biological properties of a stream. Natural short- and long-term variation of streamflow is part of the normal processes of a river or stream whereas artificial short- and long-term fluctuations can disrupt the natural processes of a river. It is critical to recognize and identify such artificial fluctuations and disturbances to have a more complete understanding of river systems. This understanding can be used to modify current management efforts to achieve more natural flow regimes. A new procedure using dual-timescale graphs is presented to visualize streamflow characteristics and to measure temporal change objectively. Theoretical development, procedural guidelines, and interpretation of results are included in the development of this new approach. The raster-based method is applied to two large river systems in the western United States. Data from twelve U.S. Geological Survey (USGS) streamflow stations within the middle and upper Snake River Basin and upper Colorado River Basin were analyzed using a dual-timescale raster-grid to identify flow signatures and disturbances. Patch-analysis and pattern quantification techniques used in landscape ecology were applied to dual-timescale raster-based hydrographs. Both river basins included gaging stations where minimal human-caused disturbances have taken place within the respective watershed. These stations function as control sites for interpretation of grid-correlograms and patch-analysis results.
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3

Mayers, Margaret Grace. "A study of four raster-based data generalization procedures." Thesis, Virginia Tech, 1987. http://hdl.handle.net/10919/40979.

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Strategies for generalizing raster-based land cover data were investigated. Generalization strategies were studied as part of the U.S. Geological Survey's (USGS) Federal Land Information System (FLIS). Area filtering, category aggregation, resampling, and modal search and replace comprised the strategies tested on USGS Alaska Interim Land Cover data. Generalization of the land cover data was deemed necessary for two reasons: 1) reduction in the volume of homogeneous land cover regions required for computer memory storage, and 2) simplification of the highly complex land cover map. The generalization strategies were evaluated based upon how well they maintained the integrity of land cover information while minimizing the number of homogeneous land cover regions. Maintenance of land cover information after application of a generalization strategy was measured by omission and commission errors, percent unchanged, Cohen's statistic, and the number of land cover regions.
Master of Science
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4

Alexander, Julie G. "Hydrographic Surface Modeling Through A Raster Based Spline Creation Method." ScholarWorks@UNO, 2014. http://scholarworks.uno.edu/td/1842.

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The United States Army Corp of Engineers relies on accurate and detailed surface models for various construction projects and preventative measures. To aid in these efforts, it is necessary to work for advancements in surface model creation. Current methods for model creation include Delaunay triangulation, raster grid interpolation, and Hydraulic Spline grid generation. While these methods produce adequate surface models, attempts for improved methods can still be made. A method for raster based spline creation is presented as a variation of the Hydraulic Spline algorithm. By implementing Hydraulic Splines in raster data instead of vector data, the model creation process is streamlined. This method is shown to be more efficient and less computationally expensive than previous methods of surface model creation due to the inherent advantages of raster data over vector data.
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5

Edwards, Aron Shaun. "Raster based coastal marsh classification within the Galveston Bay ecosystem, Texas." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2592.

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6

Yu, Jinsongdi [Verfasser]. "Towards a Specification-based Quality Guarantee for Geo Raster Web Services / Jinsongdi Yu." Bremen : IRC-Library, Information Resource Center der Jacobs University Bremen, 2012. http://d-nb.info/1035219662/34.

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7

Niesterowicz, Jacek. "Unsupervised pattern-based regionalization of large multi-categorical raster maps using machine vision methods." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1490351367846515.

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8

Burgholzer, Robert William. "Using Accumulation Based Network Identification Methods to Identify Hill Slope Scale Drainage Networks in a Raster GIS." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/32001.

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The simple accumulation-based network identification method (ANIM) in a raster Geographic Information System (GIS) posed by Oâ Callaghan and Mark (1984) has been criticized for producing a spatially uniform drainage density (Tarboton 2002) at the watershed scale. This criticism casts doubt on the use of ANIMs for deriving properties such as overland flow length for nonpoint source pollution models, without calibrating the accumulation threshold value. However, the basic assumption that underlies ANIMs is that convergent topography will yield a more rapid accumulation of cells, and thus, more extensive flow networks, with divergent, or planar terrain yielding sparser networks. Previous studies have focused on networks that are coarser than the hill-slope scale, and have relied upon visual inspection of drainage networks to suggest that ANIMs lack the ability to produce diverse networks. In this study overland flow lengths were calculated on a sub-watershed basis, with standard deviation, and range calculated for sub-watershed populations as a means of quantifying the diversity of overland flow lengths produced by ANIM at the hill slope scale. Linear regression and Spearman ranking analyses were used to determine if the methods represented trends in overland flow length as suggested by manual delineation of contour lines. Three ANIMs were analyzed: the flow accumulation method (Oâ Callaghan and Mark, 1984), the terrain curvature method (Tarboton, 2000) and the ridge accumulation method (introduced in this study). All three methods were shown to produce non-zero standard deviations and ranges using a single support area threshold, with the terrain curvature method producing the most diverse networks, followed by the ridge accumulation method, and then the flow accumulation method. At an analysis unit size of 20 ha, the terrain curvature method produced a standard deviation that was most similar to those suggested by the contour crenulations, -13.5%, followed by the ridge accumulation method, -21.5%, and the flow accumulation method, -61.6%. The ridge accumulation produced the most similar range, -19.1%, followed by terrain curvature, -24.9%, and flow accumulation, -65.4%. While the flow accumulation networks had a much narrower range of predicted flow lengths, it had the highest Spearman ranking coefficient, Rs=0.722, and linear regression coefficient, R2=0.602. The terrain curvature method was second, Rs=0.641, R2=0.469, and then ridge accumulation, Rs=0.602, R2=0.490. For all methods, as threshold values were varied, areas of dissimilar morphology (as evidenced by the common stream metric stream frequency) experienced changes in overland flow lengths at different rates. This results in an inconsistency in ranking of sub-watersheds at different thresholds. When thresholds were varied to produce average overland flow lengths from 75 m to 150 m, the terrain curvature method showed the lowest incidence of rank change, 16.05%, followed by the ridge accumulation method, 16.73%, then flow accumulation, 25.18%. The results of this investigation suggest that for all three methods, a causal relationship exists between threshold area, underlying morphology, and predicted overland flow length. This causal relationship enables ANIMs to represent contour network trends in overland flow length with a single threshold value, but also results in the introduction of rank change error as threshold values are varied. Calibration of threshold value (varying threshold in order to better match observed overland flow lengths) is an effective means of increasing the accuracy of ANIM predictions, and may be necessary when comparing areas with different stream frequencies. It was shown that the flow accumulation method produces less diverse networks than the terrain curvature and ridge accumulation methods. However, the results of rank and regression analyses suggest that further investigation is required to determine if these more diverse ANIM are in fact more accurate than the flow accumulation method.
Master of Science
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9

Wang, Huan. "A Large-scale Dynamic Vector and Raster Data Visualization Geographic Information System Based on Parallel Map Tiling." FIU Digital Commons, 2011. http://digitalcommons.fiu.edu/etd/550.

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With the exponential increasing demands and uses of GIS data visualization system, such as urban planning, environment and climate change monitoring, weather simulation, hydrographic gauge and so forth, the geospatial vector and raster data visualization research, application and technology has become prevalent. However, we observe that current web GIS techniques are merely suitable for static vector and raster data where no dynamic overlaying layers. While it is desirable to enable visual explorations of large-scale dynamic vector and raster geospatial data in a web environment, improving the performance between backend datasets and the vector and raster applications remains a challenging technical issue. This dissertation is to implement these challenging and unimplemented areas: how to provide a large-scale dynamic vector and raster data visualization service with dynamic overlaying layers accessible from various client devices through a standard web browser, and how to make the large-scale dynamic vector and raster data visualization service as rapid as the static one. To accomplish these, a large-scale dynamic vector and raster data visualization geographic information system based on parallel map tiling and a comprehensive performance improvement solution are proposed, designed and implemented. They include: the quadtree-based indexing and parallel map tiling, the Legend String, the vector data visualization with dynamic layers overlaying, the vector data time series visualization, the algorithm of vector data rendering, the algorithm of raster data re-projection, the algorithm for elimination of superfluous level of detail, the algorithm for vector data gridding and re-grouping and the cluster servers side vector and raster data caching.
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10

Duerksen, Joel L. "A comparative analysis of the performance of floating point and integer based line drawing algorithms for raster displays." Virtual Press, 1988. http://liblink.bsu.edu/uhtbin/catkey/544005.

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In order to predict and analyze the performance of both floating point and integer line drawing algorithms the performance of individual instructions is examined. A select group of line drawing algorithms are implemented and timed in performance tests. An algorithms accuracy is observed along with its performance in three tests. These tests are performed on five computers for comparison. The effects of utilizing the standard code optimizer is included as an integral part of the research.
Department of Computer Science
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11

Basnet, Badri Bahadur. "Geographic Information System based manure application planning." University of Southern Queensland, Faculty of Engineering and Surveying, 2002. http://eprints.usq.edu.au/archive/00001410/.

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[Abstract]: The disposal of animal waste has become a problem in many parts of the world due to the rapid growth in the number and the size of intensive animal industries. Safe waste disposal sites are rarely available and the relocation and/or treatment of animal waste is seldom economically viable. The reuse of animal waste for energy recovery and re-feeding is also not popular. Animal waste is a valuable source of plant nutrients and a very good soil conditioner, and has been commonly applied as fertiliser to agricultural fields. However, due to the increasing oversupply of animal waste in recent years, it has often been applied in excess to the agricultural fields. Excessive application of animal waste, without due consideration of its implications, is a serious concern. The run-off and leaching losses of nutrients from the fields fertilised with animal waste have contributed significantly to the eutrophication and toxic blue-green algae blooms in surface water systems and nitrification of ground water systems. It has also led to nutrient imbalances in the soils and odour pollution to the surrounding communities. The animal waste, which is a valuable source of plant nutrients, has thus become both an economic and environmental burden, and there is a need to develop a strategy for its sensible use as a fertiliser in agricultural fields. Sensible use of animal waste involves the consideration of all the agricultural, environmental, social, and economical limitations. A rational method of achieving this is to restrict the use of animal waste to sites suitable for such uses, identify areas where it can be relocated and applied economically, limit the application rates to a safe level, and observe appropriate manure management practices. This study addressed each of these components by developing a comprehensive manure application plan (MAP) for the site-specific use of animal waste as fertiliser in agricultural fields. Various geographic information systems (GIS) based techniques, including a weighted linear combination model and map algebra based cartographic modelling, were employed to achieve the goal. The appropriateness of the existing techniques and procedures were evaluated and modified to meet the current input requirements. New methods of analysis were devised as necessary. The Westbrook sub-catchment of the Condamine River catchment in south-east Queensland was selected as the study area. The sub-catchment covers 24,903 hectares and contains 39 intensive animal industries. The catchment is also a part of the Murray-Darling Basin, which has been suffering from toxic blue green algae blooms recurrently since 1991. This study identified that only about one-fifth of the sub-catchment area is suitable for animal waste application. Depending on the method of site suitability analysis and the number of input factors used the suitable area ranged between 16 and 22 percent. This comparatively small area is mainly due to the presence of a large proportion of non-agricultural areas in the sub-catchment. The suitable areas were also found to have various degrees of suitability for waste application. However, the degree of site suitability was affected by the number of input factors used in the analysis, the weighting of the factors, and the method of factor attribute standardisation. Conventional methods of weighting input factors were found to be cumbersome and not particularly suitable. Hence, this study developed a new ‘objective oriented comparison’ method of factor weighting. Standardisation of input factors using a continuous, rather than discrete, classification (ie fuzzy set) method was found to be more consistent in degree of suitability determination. The discrete classification of factor attributes into classes of different numbers and sizes, and the weighting of classes to a sum of one, were identified as a limitation in using this standardisation method. A new ‘weight adjustment’ method was devised and demonstrated to reduce factor-weighting biases. The suitable sites, degree of site suitability, and other relevant spatial and non-spatial information were processed within a GIS framework to develop a comprehensive manure application plan. The inherently high presence of available phosphorus in the soils of the study area was recognised and the P2O5 content in the manure was used as the basis for determining manure application rates. A complimentary nitrogen supply map was also generated. Manure management practices applicable to the areas with a lower degree of suitability were also suggested.
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12

Lo, Shin-en. "A Fire Simulation Model for Heterogeneous Environments Using the Level Set Method." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/cgu_etd/72.

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Wildfire hazard and its destructive consequences have become a growing issue around the world especially in the context of global warming. An effective and efficient fire simulation model will make it possible to predict the fire spread and assist firefighters in the process of controlling the damage and containing the fire area. Simulating wildfire spread remains challenging due to the complexity of fire behaviors. The raster-based method and the vector-based method are two major approaches that allow one to perform computerized fire spread simulation. In this thesis, we present a scheme we have developed that utilizes a level set method to build a fire spread simulation model. The scheme applies the strengths and overcomes some of the shortcomings of the two major types of simulation method. We store fire data and local rules at cells. Instead of calculating which are the next ignition points cell by cell, we apply Huygens' principle and elliptical spread assumption to calculate the direction and distance of the expanding fire by the level set method. The advantage to storing data at cells is that it makes our simulation model more suitable for heterogeneous fuel and complex topographic environment. Using a level set method for our simulation model makes it possible to overcome the crossover problem. Another strength of the level set method is its continuous data processing. Applying the level set method in the simulation models, we need fewer vector points than raster cells to produce a more realistic fire shape. We demonstrate this fire simulation model through two implementations using narrow band level set method and fast marching method. The simulated results are compared to the real fire image data generated from Troy and Colina fires. The simulation data are then studied and compared. The ultimate goal is to apply this simulation model to the broader picture to better predict different types of fires such as crown fire, spotting fires, etc.
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Syphard, Alexandra Dunya. "A raster-based GIS analysis of the cumulative impacts of humans and beaver on wetland area and types in the Chickahominy River watershed (Virginia, USA) from 1953 to 1994." VCU Scholars Compass, 1998. https://scholarscompass.vcu.edu/etd/5538.

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Despite increased recognition of wetland functions and values, wetland loss and degradation continues in the United States. Digital wetlands and uplands coverages were analyzed to compare the cumulative impacts of humans and beaver (Castor canadensis) on wetland types in the Chickahominy River watershed (Virginia, USA) from 1953 to 1994. A vector-based approach was used for data manipulation, and a raster-based approach was chosen to analyze geographic change over time. Study findings indicated that anthropogenic activities were responsible for both wetland loss and gain in the watershed, and beavers substantially influenced shifting between wetland types. Wetland area increased 4% over 41 years.
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Seegmiller, Lindsi. "Modeling and optimization of least-cost corridors." Licentiate thesis, KTH, Geoinformatik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-291279.

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Given a grid of cells, each having a value indicating its cost per unit area, a variant of the least-cost path problem is to find a corridor of a specified width connecting two termini such that its cost-weighted area is minimized. A computationally efficient method exists for finding such corridors, but as is the case with conventional raster-based least-cost paths, their incremental orientations are limited to a fixed number of (typically eight orthogonal and diagonal) directions, and therefore, regardless of the grid resolution, they tend to deviate from those conceivable on the Euclidean plane. Additionally, these methods are limited to problems found on two-dimensional grids and ignore the ever-increasing availability and necessity of three-dimensional raster based geographic data. This thesis attempts to address the problems highlighted above by designing and testing least-cost corridor algorithms. First a method is proposed for solving the two-dimensional raster-based least-cost corridor problem with reduced distortion by adapting a distortion reduction technique originally designed for least-cost paths and applying it to an efficient but distortionprone least-cost corridor algorithm. The proposed method for distortion reduction is, in theory, guaranteed to generate no less accurate solutions than the existing one in polynomial time and, in practice, expected to generate more accurate solutions, as demonstrated experimentally using synthetic and real-world data. A corridor is then modeled on a threedimensional grid of cost-weighted cubic cells or voxels as a sequence of sets of voxels, called ‘neighborhoods,’ that are arranged in a 26-hedoral form, design a heuristic method to find a sequence of such neighborhoods that sweeps the minimum cost-weighted volume, and test its performance with computer-generated random data. Results show that the method finds a low-cost, if not least-cost, corridor with a specified width in a threedimensional cost grid and has a reasonable efficiency as its complexity is O(n2) where n is the number of voxels in the input cost grid and is independent of corridor width. A major drawback is that the corridor found may self-intersect, which is often not only an undesirable quality but makes the estimation of its cost-weighted volume inaccurate.
Med tanke på ett rutnät av celler, som vart och ett har ett värde som indikerar dess kostnad per areaenhet, är en variant av det billigaste banproblemet att hitta en korridor med en specificerad bredd som förbinder två terminaler så att dess kostnadsviktade område minimeras. Det finns en beräkningseffektiv metod för att hitta sådana korridorer, men som är fallet med konventionella rasterbaserade lägsta kostnadsspår är deras inkrementella orienteringar begränsade till ett fast antal (vanligtvis åtta ortogonala och diagonala) riktningar, och därför, oavsett nätupplösning tenderar de att avvika från de tänkbara på det euklidiska planet. Dessutom är dessa metoder begränsade till problem som finns i tvådimensionella nät och ignorerar den ständigt ökande tillgängligheten och nödvändigheten av tredimensionell rasterbaserad geografisk data. Denna avhandling försöker ta itu med problemen som belyses ovan genom att utforma och testa korridoralgoritmer till lägsta kostnad. Först föreslås en metod för att lösa det tvådimensionella rasterbaserade problemet med billigaste korridorer med minskad förvrängning genom att anpassa en distorsionsminskningsteknik som ursprungligen utformades för billigaste vägar och tillämpa den på en effektiv men distorsionsbenägen billigaste korridoralgoritm. Den föreslagna metoden för distorsionsminskning är i teorin garanterad att generera inte mindre exakta lösningar än den befintliga i polynomtid och i praktiken förväntas generera mer exakta lösningar, vilket demonstreras experimentellt med syntetiska och verkliga data. En korridor modelleras sedan på ett tredimensionellt rutnät av kostnadsvägda kubikceller eller voxels som en sekvens av uppsättningar av voxels, kallade "stadsdelar", som är ordnade i en 26-hedoral form, designar en heuristisk metod för att hitta en sekvens av sådana stadsdelar som sveper den lägsta kostnadsviktade volymen och testar dess prestanda med datorgenererade slumpmässiga data. Resultaten visar att metoden hittar en låg kostnad, om inte minst kostnad, korridor med en specificerad bredd i ett tredimensionellt kostnadsnät och har en rimlig effektivitet eftersom dess komplexitet är O (n2) där n är antalet voxlar i ingångskostnadsnätet och är oberoende av korridorbredd En stor nackdel är att korridoren som hittas kan korsa sig själv, vilket ofta inte bara är en oönskad kvalitet utan gör uppskattningen av dess kostnadsviktade volym felaktig.

QC 20210309

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15

Wu, Ying. "COTS GIS integration and its SOAP-based web services." ScholarWorks@UNO, 2004. http://louisdl.louislibraries.org/u?/NOD,99.

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Thesis (M.S.)--University of New Orleans, 2004.
Title from electronic submission form. "A thesis ... in partial fulfillment of the requirements for the degree of Master of Science in the Department of Computer Science."--Thesis t.p. Vita. Includes bibliographical references.
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Gumos, Aleksander Karol. "Modelling the Cross-Country Trafficability with Geographical Information Systems." Thesis, Linköping University, Department of Computer and Information Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-313.

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The main objectives of this work were to investigate Geographical Information Systems techniques for modelling a cross-country trafficability. To accomplished stated tasks, reciprocal relationships between the soil deposits, local hydrology, geology and geomorphology were studied in relation to the study area in South-Eastern Sweden.

Growing awareness of nowadays users of GIS in general is being concentrated on understanding an importance of soil conditions changed after cross-country trafficability. Therefore, in this thesis, constructing of the Soil Knowledge Database introduced to the genuine geological soil textural classes a new, modified geotechnical division with desirable for off-road ground reasoning measurable factors, like soil permeability, capillarity or Atterberg’s consistency limits.

Digital Elevation Model, the driving force for landscape studies in the thesis, was carefully examined together with the complementary datasets of the investigated area. Testing of the elevation data was done in association to the hydrological modelling, which resulted with the Wetness Index map. The three distinguishable soil wetness conditions: dry, moist and wet, were obtained, and used consequently for creation of the static ground conditions map, a visible medium of soils susceptibility to for example machine compaction.

The work resulted with a conceptual scheme for cross-country trafficability modelling, which was put into effect while modeling in GIS. As a final outcome, by combining all processed data together, derivatives were incorporated and draped over the rendered 3D animating scene. A visually aided simulation enabled to concretized theoretical, hypothetical and experimental outcomes into one coherent model of apprised under Multicriterial Evaluation techniques standardized factor maps for ground vehicle maneuverability. Also further steps of research were proposed.

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Poulsen, Henrik. "Potential of GPU Based Hybrid Ray Tracing For Real-Time Games." Thesis, Blekinge Tekniska Högskola, Avdelningen för för interaktion och systemdesign, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3488.

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The development of Graphics Hardware Technology is blazing fast, with new and more improved models, that out spec the previous generations with leaps and bounds, before one has the time to digest the potential of the previous generations computing power. With the progression of this technology the computer games industry has always been quick to adapt this new power and all the features that emerge as the graphic card industry learn what the customers need from their products. The current generations of games use extraordinary visual effects to heighten the immersion into the games, all of which is thanks to the constant progress of the graphics hardware, which would have been an impossibility just a couple of years ago. Ray tracing has been used for years in the movie industry for creation of stunning special effects and whole movies completely made in 3D. This technique for giving realistic imagery has always been for usage exclusively for non-interactive entertainment, since this way of rendering an image is extremely expensive when it comes to computations. To generate one single image with Ray Tracing you might need several hundred millions of calculations, which so far haven’t been proven to work in real-time situations, such as for games. However, due to the continuous increase of processing power in Graphical Processing Units, GPUs, the limits of what can, and cannot, be done in real-time is constantly shifting further and further into the realm of possibility. So this thesis focuses upon finding out just how close we are to getting ray tracing into the realm of real-time games. Two tests were performed to find out the potential a current (2009) high-end computer system has when it comes to handling a raster - ray tracing hybrid implementation. The first test is to see how well a modern GPU handles rendering of a very simple scene with phong shading and ray traced shadows without any optimizations. And the second test is with the same scenario, but this time done with a basic optimization; this last test is to illustrate the impact that possible optimizations have on ray tracers. These tests were later compared to Intel’s results with ray tracing Enemy Territory: Quake Wars.
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Ollinger, Christoph German Josef. "A waveguide-based lens-less x-ray microscope." Doctoral thesis, [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/ollinger.

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Gupta, Amar. "Grid based raster selection and vector extraction /." 2006. http://digital.library.okstate.edu/etd/umi-okstate-2054.pdf.

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Lin, Hong Yue, and 林宏嶽. "Raster based spatial analysis for landfill siting." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/94555035991486337805.

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Chih, Pin-shen, and 池品軒. "Automatically Vectorizing Raster Image based on Diffusion Curves." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/82900629675918303069.

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碩士
國立交通大學
資訊科學與工程研究所
102
Diffusion curve is a novel vector-based primitive. It partitions the space through which it is drawn and define colors on each side. These colors smoothly diffuse outwards from each side until they cover the entire image. In this thesis, we propose a method to automatically vectorize a raster image. Our method extracts the contour, color and blur attribute from the raster image, and represents the raster image by the geometry primitives of diffusion curves. The vector graphics, which is represented by a set of diffusion curves closely approximates the original image, can be easily edited or animated.
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王啟凱. "A Study of a Raster-Based Geographical Information System Combined with Object-oriented Database." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/06509365117472172749.

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碩士
國防管理學院
資源管理研究所
85
Geographical information system (GIS) has already been considered as an important tool in military or civilian applications. Less integration and disagreement with the real world are the relational database's shortages. The objective of this research is to develop a GIS based on the Gargantini's linear quadtree coding scheme with the object-oriented (OO) analysis and design concept. The Dorado, an object-oriented database management system (OODBMS), is applied to implement the proposed GIS.   The Gargantini's linear quadtree coding scheme has advantages of simple algorithm and easy implementation. Object-oriented design and analysis is a useful methodlogy to develop software systems. The proposed raster-based GIS using Two-Level Object-Oriented Model is a new method to demonstrate the feasibility of this research direction. Information in a raster-based map can be classified into many blocks and layers, every block and layer is viewed as a object. The characteristics and relationship among spatial data implied in quaternary codes are transformed into the attributes of objects.   According to the implementation of the prototype system, using information query and every kind of basic operations to test and verify its feasibility.
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23

Li, Ming-Ju, and 李明儒. "A sensitivity analysis of raster-based land use change model in multi spatial scales." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/03700055123623407803.

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Abstract:
碩士
國立臺灣大學
建築與城鄉研究所
96
There are many kinds of factors to impact on the land use pattern, because of it’s complicating interactive process, in recent years, many researchers expected to explain the process of environmental dynamic changes by finding the driving forces of land use or land cover change. In many land use change studies or simulations, most of researchers will convert vector data to raster data format, using the regular grid to be a basic unit for analyzing and simulating. At this time, grid is a basic unit to represent spatial information, it means when we chose the basic grid size, we also set the spatial resolution of the research. This study detects driving forces of land use change at different spatial resolution and extent. The outcomes show that when the basic grid size was too large, it will lead to detect wrong driving forces. At different sub-areas, driving forces have little differences. The result shows that before doing land use/cover change research, we should evaluate which grid size is suitable for the research area, research area should be divided to many sub-region when it’s geographical or social economical features are quite different.
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24

Hsu, Chien-Liang, and 徐建樑. "Location Selection Using Raster-based GIS : A Study on Siting Mobile Phone Base Stations." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/gfckhv.

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Abstract:
碩士
朝陽科技大學
建築及都市設計研究所
93
With the advent of mobile communication technology, the adoption rate of mobile phone in Taiwan is said to be over 80% of its population. Because of the basic requirement to offer good communication quality, the mobile phone system providers are constantly siting base stations as needed in order to provide enough signal coverage and strength. This research first discusses those issues related to siting mobile phone base stations, such as the location, the quantity, the radio signal coverage, the channel capacity of each base station, etc. It then uses the GRASS(Geographic Resource Analysis Support System), which is an open source Geographic Information System (GIS), combined with Location / Allocation theory to analyze the current issues of siting mobile phone base stations and devise improved solutions. Finally the Wufeng’s urbanized area of Taichung country is used as the study area to analyze the current issues and verify both enabled the mobile phone base station system to achieve the good quality on location set and the proper attention to mobile phone base station established efficiency.
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25

Liu, Hsiao-Yun, and 劉曉芸. "Investigating the Impact of Land Use Changes on Groundwater Recharge Using Raster Based Geographic Information System." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/98naje.

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Abstract:
碩士
國立交通大學
土木工程系所
104
The groundwater, providing fresh water for 1/3 of total water demand in Taiwan, is an important fresh water resource. Proper management is critical for sustainable use of the groundwater. Simulation models have been intensively used for the water resources evaluation. One of the most important factor is the groundwater recharge volume. This study uses python to develop a groundwater recharge evaluation platform which combines PCRaster software with raster-type data of land use, soil information, rainfall, etc. This platform is applied to estimate the groundwater recharge in Pingtung plain and study the influence of the land use associated with the groundwater recharge. The area of Pingtung plain is about 1234.26 km2. The annual groundwater recharge is between 1.2 and 2.0 billion tons of water during the period of 1999 through 2010. The average annual groundwater recharge is 1.7 billion tons with in the period. The annual precipitation in the period is 2415 mm. Accordingly, the recharge rate is about 57% in Pingtung plain. This study analyzes the relationship between the groundwater recharge and the land use. The result shows that 0.2 billion tons reduction of annual groundwater recharge if 10% of permeable land turns into impermeable. This result indicates significant impact on groundwater recharge associated with land use in Pingtung plain.
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26

Risinger, Emily Diane. "Defining GeoDesign and the emergent role of the sustainable sites initiative (SITES) for integrative project management." Thesis, 2012. http://hdl.handle.net/2152/29161.

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This report is a discussion of the multifarious applications of the modern day geographic information system and how the universal merit of the technology across disciplines has led to the emergence of GeoDesign. The purpose of this Master’s Professional Report was to retrace the core conceptual framework and landmark events occurring in the evolution GIS technology, and how these factors have led to recent creation of new performance based rating systems and evidence-based design techniques. The Sustainable Sites Initiative (SITES), a new performance based rating system that has emerged in response to the call for increased knowledge and best practices lacking in LEED, is discussed; along with integrated project management. This professional report was intended to be an exploratory discussion of the larger theoretical implications fueling the shift towards mandating greater standards for sustainable design. It offers some ideas for how we should continue evolving GeoDesign moving into the next century; and outlines the importance of all new rating systems needing to acknowledge the growing importance of GeoDesign and ever advancing imagery technologies in understanding complex system processes in the future.
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