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A Large-scale Dynamic Vector and Raster Data Visualization Geographic Information System Based on Parallel Map TilingWang, Huan 08 November 2011 (has links)
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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Activity Location Assignment Comparison Using Geospatial Landuse and Building Data in MATSim : A Multi-modal Transport Case Study of StockholmGAO, YU January 2023 (has links)
Transport simulation models play a crucial role in transportation planning, design, and operations, allowing for the replication of various scenarios through the incorporation of real-world data and parameters. Recently, agent-based transport models have gained prominence for their ability to simulate intricate metropolitan transport systems. These models take into account the distinct characteristics, decision-making processes, and interactions of individual agents. Among the array of agent-based transport models, MATSim stands out as a potent and adaptable tool for modeling transportation systems. A critical aspect of MATSim’s input preparation involves assigning activity location points using land use raster data. However, the characteristics of land use raster data present limitations in certain urban case studies such as Stockholm. In response, some researchers have turned their attention to buildings shapefile data, a commonly used geospatial data format. This study aims to improve the activity location assignment model by developing an evaluation workflow of model uncertainty for different geospatial input data in MATSim and empirically analyzing their impacts on simulation outcomes. Despite acknowledging data availability and activity representation limitations, the study’s results demonstrate that utilizingbuildings shapefiles as input data yields more consistent outcomes with reduced uncertainty. This suggests the promising potential of buildings shapefiles as a favorable data source for transportation modeling and planning within the studied scenarios.
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Development Of A Methodology For Geospatial Image StreamingKivci, Erdem Turker 01 September 2010 (has links) (PDF)
Serving geospatial data collected from remote sensing methods (satellite images, areal photos, etc.) have become crutial in many geographic information system (GIS) applications such as disaster management, municipality applications, climatology, environmental observations, military applications, etc. Even in today&rsquo / s highly developed information systems, geospatial image data requies huge amount of physical storage spaces and such characteristics of geospatial image data make its usage limited in above mentioned applications. For this reason, web-based GIS applications can benefit from geospatial image streaming through web-based architectures. Progressive transmission of geospatial image and map data on web-based architectures is implemented with the developed image streaming methodology. The software developed allows user interaction in such a way that the users will visualize the images according to their level of detail. In this way geospatial data is served to the users in an efficient way. The main methods used to transmit geospatial images are serving tiled image pyramids and serving wavelet based compressed bitstreams. Generally, in GIS applications, tiled image pyramids that contain copies of raster datasets at different resolutions are used rather than differences between resolutions. Thus, redundant data is transmitted from GIS server with different resolutions of a region while using tiled image pyramids. Wavelet based methods decreases redundancy. On the other hand methods that use wavelet compressed bitsreams requires to transform the whole dataset before the transmission. A hybrid streaming methodology is developed to decrease the redundancy of tiled image pyramids integrated with wavelets which does not require transforming and encoding whole dataset. Tile parts&rsquo / coefficients produced with the methodlogy are encoded with JPEG 2000, which is an efficient technology to compress images at wavelet domain.
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GIS obce Dolní Újezd. / GIS of Dolní Újezd municipalityKlusoňová, Pavla January 2014 (has links)
The thesis deals with geographical information systems ( GIS) which are nowadays common tools for use in civil service and local administration. The theoretical part is focused on more detailed characterization of these systems including issues concerning geographical data and data base systems. The description of the particular GIS software solution for the selected village of Dolní Újezd in the application of ArcInfo is the main contain of the practical sections. The creation of spatial analysis is a component of the project with the aim of finding a suitable location for benches for public use. The resulting project called “GIS Dolní Újezd”wil be used by the local council in Dolní Újezd.
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A Survey of Methods for Visualizing Spatio-temporal DataPersson, Mattias January 2020 (has links)
Olika typer av data genereras kontinuerligt varje sekund och för att kunna analysera denna data måste den transformeras till någon typ av visuell representation. En vanlig typ av data är spatio-temporal data, vilket är data som existerar i både rymd och tid. Hur denna typ av data kan visualiseras har undersökts under en lång period och området är fortfarande relevant idag. Ett antal metoder har undersökts i detta arbete och en genomgående litteraturstudie har genomförts. En applikation som implementerar ett antal av dessa undersökta metoder för att visualisera klimatdata har även skapats. / Different kinds of data is generated continuously every second and in order to be ableto analyze this data it has to be transformed into some kind of visual representation. Onecommon type of data is spatio-temporal data, which is data that exists in both space andtime. How to visualize this kind of data have been researched for a long time and is still avery relevant subject to expand on today. A number of approaches have been explored inthis work. An extensive literature study has also been performed and can be read in thisreport. The study has been divided into different classifications of spatio-temporal dataand the visual representations are structured by these classes.Another contribution of this thesis is a climate data application to visualize spatiotemporaldata sets of temperatures collected for several countries in the world. This applicationimplements several of the visual representations presented in the survey includedin this thesis. This resulted in a four display application, each showing a different aspect ofthe chosen data sets that consisted of climate data. The result shows how effective multiplelinked views are in order to understand different characteristics of the data.
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Modelling the Cross-Country Trafficability with Geographical Information SystemsGumos, Aleksander Karol January 2005 (has links)
<p>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.</p><p>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.</p><p>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.</p><p>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.</p>
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Modelling the Cross-Country Trafficability with Geographical Information SystemsGumos, Aleksander Karol January 2005 (has links)
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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Defining GeoDesign and the emergent role of the sustainable sites initiative (SITES) for integrative project managementRisinger, Emily Diane 16 March 2015 (has links)
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. / text
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GIS využití krajiny obce Jinačovice / Land use GIS of Jinačovice municipalityKelblová, Kristýna January 2013 (has links)
This master thesis focuses on the development of the GIS in the Jinačovice municipality, particularly on the land use. The core data used for the research has been gathered by aerial photography since 1950. Other data sources include other types of maps, especially Cadastral map, ZABAGED data and statistical data. An analysis of the Land use has been carried out as well as additional analyses of the area. The research has been conducted specifically for the Jinačovice municipality.
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Modeling and optimization of least-cost corridorsSeegmiller, Lindsi January 2021 (has links)
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. / <p>QC 20210309</p>
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