Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 15 of 15 for “"Digital Terrain Models"”.
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Digital Terrain Models for Radio Path Loss Calculations
This work addresses the problem of digital terrain modelling for estimating radio path propagation within a mobile communication system. The ideal requirements are for a data structure which is storage efficient and computationally efficient for calculating profiles, whilst elevation errors should …
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Digital terrain modelling of catchment erosion and sedimentation / Hua Sun
… was developed and interfaced with the existing digital terrain models called TAPES-C and THALES, to estimate soil erosion and deposition in Sauerbier Creek catchment.
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Analysis of the impact of using GIS and 2.5D modelling in automating the determination of view factors for the purposes of CAMA modelling
… Five metre contour data is used to generate digital terrain models (DTM) in the TIN data structure and in the raster data structure. The two terrain surfaces are assessed for accuracy by using the Town Survey Marks (TSM) height data.
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Evaluating the quality of ground surfaces generated from Terrestrial Laser Scanning (TLS) data
… Aerial Laser Scanning (ALS) data to generate Digital Terrain Models (DTM) since the 1990s, and various algorithms developed for ground point extraction have been proposed based on the characteristics of ALS data. However, Terrestrial Laser Scanning (TLS) data, which might be a better indicator …
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Analysis and exploration of virtual 3D city models using 3D information lenses
… to objects and structures of virtual 3D city models. In contrast to digital terrain models, the application of focus & context visualization to virtual 3D city models is barely researched. However, the purposeful visualization of contextual data of is extreme importance for the interactive …
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An Analysis and Critique of DEM Creaion and 3-D Modeling Using Airborne LIDAR and Photogrammetric Techniques
… tool for many engineering projects. Accurate digital representations of terrain and ground features are extremely useful for efficient design, communication and data representation in projects involving land development, transportation planning, hydrologic analysis, environmental impact …
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LiDAR duomenų taikymas partizaninių kovų paveldo objektų Lietuvoje tyrimams /
… visualization and visual analysis of the digital terrain models of the territory, the initial results of which were verified in situ; analysis of the characteristics of the LiDAR data used in the study that may have an impact on the identification of partisan heritage sites; visualization …
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Evaluating the performance of multi-rotor UAV-Sfm imagery in assessing simple and complex forest structures: comparison to advanced remote sensing sensors
… UAV-based TH estimations depend on reliable Digital Terrain Models (DTMs), while UAV-based DBH estimations depend on reliable dense photogrammetric point cloud. The main aim of this study was to evaluate the performance of multirotor UAV photogrammetric point cloud in estimating homogeneous …
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Modeling Forest Canopy Distribution from Ground-Based Laser Scanner Data
… independently on the plot. Canopy height models, digital terrain models and 3D maps of the density of canopy surfaces were created using aligned point cloud data. Finally spatially explicit models of the horizontal and vertical distribution of plant area index (PAI) and leaf area index …
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An Evaluation of DEM Generation Methods Using a Pixel-Based Landslide Detection Algorithm
The creation of landslide inventories is an important step in landslide susceptibility mapping, and automated algorithms for landslide detection will increasingly be relied upon as part of the mapping process. This study compares the effects of three different DTM generation methods on a …
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The Volcanic Evolution of Syrtis Major Planum, Mars
… and uses base layer mosaics of CTX data and CTX Digital Terrain Models. The mapping shows that there were two major phases of magmatism at Syrtis Major. The first phase (~3.6 Ga – ~3.2 Ga) consisted of tube-fed lava plains interleaved with giant (>300 km) tabular lava flows emplaced from the …
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GPS augmentation using digital spatial data
… which are used to augment GPS using a variety of digital spatial data. It is well known that the use of GPS can be severely compromised by various error sources such as signal obstructions, multipath and poor satellite geometry etc., especially in highly built-up areas. In order to improve the …
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Three dimensional measurement of textured surfaces using digital photogrammetric techniques
… to quantify the deformations of the rock face. Digital photogrammetry provides an ideally suited method of monitoring these deformations, as the necessary equipment is portable and easy to use underground, where the conditions are extreme with temperatures approaching 40°C and humidity levels …
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Large-area forest assessment and monitoring using disparate lidar datasets
… were collected mostly to aid in the creation of digital terrain models and to support hydrological and engineering assessments. Such data is not ideal for forestry purposes mainly due to the low pulse density per square meter, the high scan angles and low swath overlaps associated with these …
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Holocene sedimentary history of Chilliwack Valley, Northern Cascade Mountains
… the volume evacuated from major gully sources. Digital terrain models of paleo-surfaces are constructed to calculate total sediment erosion and deposition from tributary valleys and the mainstem. Chilliwack Lake has effectively trapped the entire post-glacial sediment load from the upper …