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.
Results
Showing 1 to 20 of 32 for “"terrain models"”.
-
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 …
-
Analysis of photogrammetrically-derived digital surface and terrain models for building recognition
… of three-dimensional CAD (computer aided design) models, is very important to many users such as architects, town planners and telecommunications and environmental engineers. This thesis examines the role of digital terrain and surface models in supporting this reconstruction process. The thesis …
-
Regularity-Preserving Terrain Simplification For Faster Line-of-Sight
Three-dimensional terrain models play a key role in many applications. Line-of-sight queries, which are important operations in some applications (e.g. battlefield simulations), test whether or not two entities can see each other over the terrain. Given enough entities and a large enough terrain, …
-
A Unified Spatial Data Structure for GIS
… buildings, the road network or the relief of the terrain. The spatial information used in GIS can be grouped into four main groups: polygonal maps, terrain models, networks and discrete, unconnected objects. Polygonal maps and terrain models are considered to be "field" models of space, covering …
-
Digital terrain modelling of catchment erosion and sedimentation / Hua Sun
… and interfaced with the existing digital terrain models called TAPES-C and THALES, to estimate soil erosion and deposition in Sauerbier Creek catchment.
-
Analysis of the impact of using GIS and 2.5D modelling in automating the determination of view factors for the purposes of CAMA modelling
… 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.
-
Evaluating the quality of ground surfaces generated from Terrestrial Laser Scanning (TLS) data
… 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 of …
-
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 and …
-
Quantifying the Impact of Seismic Lines on Methane Release in a Treed Bog Ecosystem using Unmanned Aerial Vehicles (UAVs)
… the ability to generate accurate peatland terrain models, and subsequently estimate seismic-line impacts on both physical parameters (microtopography and depth-to-water) and peatland methane emission, ultimately revealing one of the hidden impacts of seismic lines on Canada’s Boreal …
-
Beyond visualization : designing interfaces to contextualize geospatial data
… geospatial sensor data visualization and terrain models with various user interface modalities in an educational context to support data analysis and knowledge building using part-digital, part-physical rendering. The main contribution of this thesis is a concrete application scenario and …
-
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 …
-
Hazard avoidance for high-speed rough-terrain unmanned ground vehicles
… vehicles have important applications in rough-terrain. In these applications unexpected and dangerous situations can occur that require rapid hazard avoidance maneuvers. At high speeds, there is limited time to perform navigation and hazard avoidance calculations based on detailed vehicle and …
-
An Analysis and Critique of DEM Creaion and 3-D Modeling Using Airborne LIDAR and Photogrammetric Techniques
… 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 studies, and much more. Within …
-
Towards Systematic Selection of Terrain- and Ground Cover-Specific LiDAR Filtering Parameters
… is essential to creating useful bare-earth terrain models. Parameterization is particularly important in areas characterized by extremely low relief, such as the Little Red River Irrigation Project Area in central Arkansas. In this kind of landscape, analyses such as hydrological flow models …
-
Development and Evaluation of the Profile Synthesis Method for Approximate Floodplain Redelineation
… typically consist of developing new hydraulic models, or reusing existing hydraulic model results in conjunction with new, more detailed LiDAR terrain models. This research develops a profile synthesis method for redelineation of approximate flood boundaries, and evaluates the method's …
-
Evaluating the performance of multi-rotor UAV-Sfm imagery in assessing simple and complex forest structures: comparison to advanced remote sensing sensors
… 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 and …
-
Analysis of Viewshed Accuracy with Variable Resolution LIDAR Digital Surface Models and Photogrammetrically-Derived Digital Elevation Models
… of visibility between two points on the earth's terrain is a common use of GIS software. Most commercial GIS software 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 …
-
Implication of Terrain Topology Modelling on Ground Vehicle Reliability
… excitation input to a vehicle as it traverses terrain is provided by the surface topology. It is not computationally efficient to utilise physically measured terrain topology for these simulations since extremely large data sets would be required to represent terrain of all desired types. …
-
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 …
-
Delineation of Karst Potential Using LiDAR and GIS Analyses, Fort Hood Military Installation, Texas
… these systems have also been used to develop terrain models that allow the user to remotely delineate sinkholes and other surficial features. The Fort Hood Military Installation is a karst landscape that has been altered significantly for use in military training exercises. The ground surface …
Page 1 of 2