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Explanation of the BGS subsurface viewer
Get PDFThe Subsurface Viewer is a package developed by INSIGHT Geologische
Softwaresysteme GmbH for the visualisation and analysis of
digital geoscientific spatial models.
The viewer has been developed following the popularity of
INSIGHT’s Geological Surveying and Investigation in 3D (GSI3D)
software tool that is in use extensively inside the British Geological
Survey (BGS) for the construction of systematic near surface models
(Kessler and Mathers 2004; Kessler et al. 2005; Kessler et al. 2009).
These notes describe and display the use of the interface windows to
the software.
A Geological Model is embedded within the Viewer as a means of
publication and distribution to the wider world. In this way the constructed
model can be examined and analysed to produce:
models displaying the geology or other pre-selected
applied themes (e.g. hydrogeological properties)
geological maps (at surface and uncovered)
user defined synthetic borehole logs
user defined horizontal slices and vertical sections
visualisation of the geometry of single and combined
units
The model supplied with the Subsurface Viewer is encrypted and
cannot be altered, nor can users add additional data as the viewer is a
standalone package. The model and the necessary Java software and
extensions are all included in the package. The model described
herein (West Thurrock) is freely downloadable from the BGS website
at:
http://www.bgs.ac.uk/science/thamesgateway/3dModels.htm
3D terrain visualisation for GIS: A comparison of different techniques
No full textGeographic Information System (GIS) applications are now moving towards 3D as it has a better representation of the real world.Most GIS applications now can be visualised not only in 2D but also in 3D.Currently most of the applications are capable of operating in an online environment such as Google Earth, Microsoft Virtual Earth and World Wind.Recently, many people use these online applications for their daily work and also for decision making.Terrain visualisation is an important aspect for these three applications, in visualizing the world in 3D.The quality of terrain visualisation depends on the techniques used by the developer.The research for generating good quality terrain visualisation for depicting the real world is ongoing and faces big challenges. There are many techniques available that can be used to visualize the terrain in 3D such as photorealistic and non-photorealistic rendering (NPR). The aim of this paper is to compare different techniques of terrain visualisation in GIS environment. The techniques involved in this experiment are colour shading, terrain overlaid with satellite image and silhouette rendering algorithm for NPR. The comparison is based on the quality of terrain visualisation, representation of object on terrain, representation of slope, and error in terrain. Three different areas in the Universiti Putra Malaysia (UPM) were chosen for this experiment; grid Digital Elevation Model (DEM) generated from R2V software was used as topographic data and Quick Bird satellite image of UPM for satellite data. Each of the areas was tested by the three different techniques of terrain visualisation.The results from these different techniques of terrain visualisation are discussed in detail. The results of this paper will be of help to the users in identifying the best technique of terrain visualisation suitable for GIS data
Operational Digital 3D-Image Acquisition and Photogrammetric Processing with the High Resolution Stereo Camera (HRSC)
No full textAgronomic Suitability Studies in the Russian Altai Using Remote Sensing and GIS: Untersuchungen der Landwirtschaftseignung im Russischen Altai unter Verwendung von Fernerkundungsdaten und GIS
Get PDFThe doctoral thesis describes methodologies and appropriate adaptations of existing solutions to model land suitability in two ways for the valley and basin areas of the South-Siberian Altai Mountains within a geo-information system (GIS) environment. Starting-point approaches are: 1) the Agricultural Soil Suitability Model „Almagra” and Land Capability Model “Cervatana”/MicroLEIS System (De la Rosa et. al 1992, 1998) developed for Mediterranean regions and a method specifically compiled by Burlakova L. M. (1988) for the Altai based on the weighted means of a factor set. 2) For comparison purposes, second, third and fourth versions of the same model are developed using three different types of Fuzzy Logic approaches. They are used to present how Gauss membership functions of particular classes can be computed as different classes and how variables taking values in ranges can be handled in a mathematical way. Furthermore, the paper presents ideas on how remote sensing might interact with the geo-information system (GIS) where - like in the present case – the required input geo-data are not fully sufficient to (i) feed the models formalising soil and climatic conditions, and (ii) to characterise the patterns of land management within the study area. Three agricultural crops (summer wheat, sunflowers and potatoes) are relevant to the Altai Region at a regional level and are, therefore considered. A rating is classified using five suitability classes according to the FAO classification (1976). For the case study the Uimon Basin was chosen. Social and economic factors are so far excluded but can be added within a further phase of development.Diese Doktorarbeit beschreibt Methoden und geeignete Anpassungen bereits existierender Lösungen, um auf zwei verschiedenen Wegen die Landeignung für die Tal- und Beckenregionen der Südsibirischen Altaigebirges innerhalb eines Geoinformationssystems zu modellieren (GIS). Die Ausgangsmethoden sind: 1) die Bodeneignungsmodelle „Almagra" and „Cervatana“ (MicroLEIS System), entwickelt für die Mittelmeerregionen (De la Rosa et al. 1992 and 1998) und die „Gewichtsmethode“, welche Burlakova L. M. (1988) speziell für die Altairegion entwickelte. Letztgenannte Methode basiert auf den gewichteten Mitteln für eine gegebene Anzahl von Faktoren. 2) Zum Vergleich, die zweite, dritte und vierte Version des gleichen Modells mit drei unterschiedlichen Typen wurden mit Fuzzy-Logik-Methoden entwickelt. Sie werden benutzt, um darzustellen, wie unscharfe Mengen zum einen die Berechnung von Gauß-Mitgliedschaftsfunktionen bestimmter Klassen veranschaulichen können, welche zu anderen Klassen gehören, und wie die Variablen in einer mathematischen Handhabung angefasst werden können. Außerdem stellt diese Arbeit Ideen vor, wie die Fernerkundung das Geoinformationssystem (GIS) eingesetzt werden kann, wenn - wie im vorliegenden Fall - nur unzureichend Geodaten vorhanden sind, (i) um in die Modellierung der Boden- und Klimabedingungen einzugehen und (ii) um die Charakteristik des Landmanagements im Untersuchungsgebiet zu kennzeichnen. Drei landwirtschaftliche Agrarkulturen (Sommerweizen, Sonnenblumen und Kartoffeln) sind für die Altairegion auf regionaler Ebene von Bedeutung und wurden daher in die vorliegende Untersuchung einbezogen. Die Bewertung erfolgte nach fünf Eignungskategorien, entsprechend der FAO Klassifikation (1976). Das Uimon-Becken wurde als Untersuchungsgebiet ausgewählt. Soziale und ökonomische Faktoren wurden bisher ausgeschlossen, können aber innerhalb einer weiteren Entwicklungsphase hinzugenommen werden
Calculating and Visualising Terrain Slopes based on Digital Elevation Models derived from High-Resolution Stereo Images
No full textCartographic Representation of Spatial Data Quality Parameters in Volunteered Geographic Information
No full textVolunteered geographic information (VGI) are constantly being added, edited or removed by the users, so their quality is not static. As VGI users do not necessarily have high spatial knowledge, system administra-tors control the quality of information in order to provide the users with the appropriate datasets. However, quality of spatial data has several parame-ters, so the appropriate data may differ from one application to another. Unlike the geographic communities, presenting the standard metadata statements is not so efficient, as they may not be familiar for VGI users. In this paper, we propose providing VGI users with the spatial data quality parameters through simple cartographic representations and let them de-cide on appropriateness of the datasets for the application at hand. The us-ers select the desired quality parameters as well as the visualization element (e.g. color, line thickness, intensity, style, etc.) to classify the datasets. The datasets are represented by the selected element based on their metadata information, which help the users to visually evaluate the quality of da-tasets.Volunteered geographic information (VGI) are constantly being added, edited or removed by the users, so their quality is not static. As VGI users do not necessarily have high spatial knowledge, system administra-tors control the quality of information in order to provide the users with the appropriate datasets. However, quality of spatial data has several parame-ters, so the appropriate data may differ from one application to another. Unlike the geographic communities, presenting the standard metadata statements is not so efficient, as they may not be familiar for VGI users. In this paper, we propose providing VGI users with the spatial data quality parameters through simple cartographic representations and let them de-cide on appropriateness of the datasets for the application at hand. The us-ers select the desired quality parameters as well as the visualization element (e.g. color, line thickness, intensity, style, etc.) to classify the datasets. The datasets are represented by the selected element based on their metadata information, which help the users to visually evaluate the quality of da-tasets
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