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Showing 1 to 17 of 17 for “"viewshed"”.
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A GIS-Based Optical Viewshed Optimization Algorithm
Traditional viewshed analyses distinguish between those areas which can be seen from a given observation point and those which cannot be seen. Given a surface digital elevation model (DEM) and observer properties (location and height), the algorithm computes whether or not each target cell is …
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Analysis of Viewshed Accuracy with Variable Resolution LIDAR Digital Surface Models and Photogrammetrically-Derived Digital Elevation Models
… packages include the ability to generate a viewshed, or a map of terrain surrounding a particular location that would be visible to an observer. Viewsheds are often generated using "bare-earth" Digital Elevation Models (DEMs) derived from the process of photogrammetry. More detailed models, …
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The Validity of Using a Geographic Information System's Viewshed Function as a Predictor for the Reception of Line-of-Sight Radio Waves
A Geographic Information System (GIS) viewshed is the result of a function that determines, given a terrain model, which areas on a map can be seen from a given point(s), line or area. In the communications industry, this function has been used to model radio wave coverages and to site transceiver …
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PERCEPTION & ROLE OF 3-D VISUALIZATIONS IN PLANNING: A CASE STUDY OF THE NORTHWEST PASSAGE SCENIC BYWAY'S VIEWSHED PROTECTION & VISUALIZATION PROJECT
… in the Northwest Passage Scenic Byway’s (NWPSB) Viewshed Protection and Visualization project. This project, which was conducted by the NWPSB Commission and Advisory Team, provided the perfect opportunity to study the use of several 3-D visualizations including digitally altered photographs and …
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PERCEPTION & ROLE OF 3-D VISUALIZATIONS IN PLANNING: A CASE STUDY OF THE NORTHWEST PASSAGE SCENIC BYWAY'S VIEWSHED PROTECTION & VISUALIZATION PROJECT
… in the Northwest Passage Scenic Byway’s (NWPSB) Viewshed Protection and Visualization project. This project, which was conducted by the NWPSB Commission and Advisory Team, provided the perfect opportunity to study the use of several 3-D visualizations including digitally altered photographs and …
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The Effect of Digital Elevation Model Resolution on Wave Propagation Predictions at 24Ghz
… using the prediction of ESRI's ArcView® viewshed algorithm. Results show that resolutions between one-meter and thirty-meters have little effect on the aggregate accuracy of the viewshed.
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Rock Imagery: A Cultural Landscape Analysis in the Yakima Uplands
… This study also explores the potentials of using viewshed analysis to examine the cultural landscape. The documentation and locational analysis support recommendations for future study and protection of rock image sites. There are currently twelve known rock imagery sites at the Joint Base …
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Factors affecting piping plover (Charadrius melodus) nest site selection following landscape and predator community changes
… site selection and the area visible from nests (viewshed) and evaluated its addition in nest site selection models including habitat variables. Piping plovers exhibited a preference for nest sites with increased predator visibility compared to random selection, indicating a strategic selection …
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Prediction of Building Count and Dimensions from U.S. Census Data Using Multiple Regression
… place transmitters to reach potential customers. Viewshed analysis, a technique found in Geographic Information Systems (GIS) software, can be used to model propagation of the wireless signals from different locations to find the best transmitter site. To carry out viewshed analysis, digital data …
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High Performance Geospatial Analysis on Emerging Parallel Architectures
… parallelism in several GIS-applied algorithms: viewshed calculation, image feature transform, and feature analysis. It presents implementations of these algorithms that exploit parallel processing to reduce execution time, and analyzes the effectiveness of the implementations in their use of …
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Effect of field-of-view on perceived representativeness and preference of visual simulations
… the test sites, regardless of the scenes viewshed. Preference ratings for the same images were analyzed and compared with response to representativeness. The results of the study reveal no relationship between image preference and the perceived accuracy of the images to represent the test …
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Resource Protection: a Model For National Parks
… a set of policy recommendations to preserve the viewshed of these three points. Additionally, guidelines were developed that other national park managers can use when constructing a resource protection plan designed specifically to protect their park's unique resources.
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Autonomous Navigation of a Ground Vehicle to Optimize Communication Link Quality
… GIS data is used primarily for evaluating the viewshed, or line-of-sight, between two network subsystems using elevation data. However, infrastructure and ground cover data are also considered in navigation planning. Both concepts prove to be powerful tools for effective autonomous …
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Mapas de visibilidade em grandes terrenos representados por grades regulares
… consiste no cálculo de mapas de visibilidade, ou viewsheds. Um mapa de visibilidade indica quais regiões de um terreno são visíveis a partir de um determinado ponto de observação, normalmente chamado de observador. Este trabalho apresenta dois novos algoritmos para cálculo de viewshed em grandes …
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Estrategias para la evaluación del impacto visual de plantas fotovoltaicas mediante sistemas de información geográfica
… 1). Esta metodología se basa en métodos de fuzzy viewshed (cuencas visuales difusas) y decaimiento visual con la distancia, que permiten calcular el número máximo de horas, de un día medio, en las que la nueva planta fotovoltaica puede ser vista por cada posible observador. Este observador puede …
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Crash severity modeling in transportation systems
… a geographic information system (GIS)-based viewshed analysis is developed to identify the locations that do not conform to AASHTO (2011) criteria regarding stopping and decision sight distances, which could then be used as potential risk factors in crash prediction. Moreover, this method …
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GIS and Satellite Visibility: Viewsheds from Space
… tool, a customization of ArcGIS named Satellite Viewsheds, which predicts satellite visibility for any place and time while considering line of sight obstructions. Satellite Viewsheds requires a raster surface model, the test date and time, and the orbital properties of the satellites. It …