The study investigated vulnerability of vegetation to El-Niño Southern Oscillation (ENSO) over Africa by correlating Normalized Difference Vegetation Index (NDVI) data from the Advanced Very High Resolution Radio...
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The Internet has redifined how maps are used. No longer restricted to paper, maps are now transmitted almost instantly and delivered to the user in a fraction of the time required to distribute maps on paper. They are...
ISBN:
(数字)9783540720294
ISBN:
(纸本)9783540720287
The Internet has redifined how maps are used. No longer restricted to paper, maps are now transmitted almost instantly and delivered to the user in a fraction of the time required to distribute maps on paper. They are viewed in a more timely fashion. Weather maps, for example, are updated continously throughout the day. Most importantly, maps on the Internet are more interactive. They are accessed through a hyperlinking structure that makes it possible to engage the map user on a higher-level than is possible with a map on paper. Finally, the Internet is making it possible to more easily distribute different kinds of cartographic displays such as animations. The Internet presents the map user with both a faster method of map distribution and different forms of mapping. This book provides an international perspective on this growing area of information dissemination.
This book addresses the Geographic Information Systems (GIS) and Remote Sensing communities worldwide by presenting a collection of 43 peer-reviewed interdisciplinary perspectives on Object-Based Image Analysis (OBIA)...
ISBN:
(数字)9783540770589
ISBN:
(纸本)9783540770572
This book addresses the Geographic Information Systems (GIS) and Remote Sensing communities worldwide by presenting a collection of 43 peer-reviewed interdisciplinary perspectives on Object-Based Image Analysis (OBIA). OBIA is a recent sub-discipline of Geographic Information Science devoted to developing automated methods to partition remote sensing imagery into meaningful image-objects, and assessing their characteristics through spatial, spectral and temporal scales. Its applications range from agriculture and natural resource management, to national defense and global climate change. Its economic impact spans from data collection, hardware and software vendors, developers and users, to recipients of sound sustainable environmental policy. Its effect is to synergistically bridge the raster world of remote sensing and the vector world of GIS by generating new semantically rich queryable geographic-information from multiscale earth observation data. We invite you to join us on this exciting state-of-the art journey into OBIA. The accompanying CD includes high resolution figures.
Modelling and managing topology in 3D CIS is a non-trivial task. The traditional approaches for modelling topological data in 2D CIS cannot be easily extended into higher dimensions. In fact, the topology of real 3D m...
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ISBN:
(纸本)9783540721345
Modelling and managing topology in 3D CIS is a non-trivial task. The traditional approaches for modelling topological data in 2D CIS cannot be easily extended into higher dimensions. In fact, the topology of real 3D models is much more complex than that of the 2D and 2.5D models used in classical GIS;in consequence there is a great number of different 3D spatial models ranging from constructive solid geometry to boundary representations. The choice of a particular representation is generally driven by the requirements of a given application. Nevertheless, from a data management point of view, it would be useful to provide a general topological model handling 2D, 2.5D and 3D models in a uniform way. In this paper we describe concepts and the realisation of a general approach to modelling and managing topology in a 3D CIS based on oriented d-Generalised Maps and the closely related cell-tuple structures. As an example of the applicability of the approach, the combination of a group of buildings from a 3D city model with the corresponding part of a 2D city is presented. Finally, an outlook to ongoing research is given in the context of topological abstraction for objects represented in multi-representation databases.
This paper describes the production process of 3D maps at Tele Atlas. Starting from a 2D City map which contains relevant features by their outline, 3D City maps are created by adding height to the outlines of buildin...
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ISBN:
(纸本)9783540721345
This paper describes the production process of 3D maps at Tele Atlas. Starting from a 2D City map which contains relevant features by their outline, 3D City maps are created by adding height to the outlines of buildings and other objects. Further enhancements are made by adding roof representations and facade textures. These textures can either be an exact representation of the facade or be composed of predefined elements from a library which leads to significant data size reductions. In the production process, Mobile Mapping a technology developed at Tele Atlas plays an important role. It serves to collect building heights and facade textures and components. To date this has resulted in the availability of 3D City maps of 12 cities with important extension planned for 2008. The paper ends by stating that whereas the original reason to develop 3D maps stems from a desire to improve the riser interface of navigation and other Intelligent Transport applications, it is likely that 3D models will have growing significance in future also for in-car safety systems.
Once 3D information is acquired and used for their initial applications, it is likely that the original source data or its derived products can be re-used. The purpose of this paper is to show the large potential for ...
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ISBN:
(纸本)9783540721345
Once 3D information is acquired and used for their initial applications, it is likely that the original source data or its derived products can be re-used. The purpose of this paper is to show the large potential for re-using 3D geo-information. The focus is on the re-use of laser scanner data and its derived products at four major geo-organisations in The Netherlands. Reusing data is not only of interest for end-users but especially for data owners who can better justify the costs for acquisition and maintenance of the data. We analyzed the flexibility of organizations to explore what can be done with the data in their possession. We found that once a 3D data set was acquired with requirements based on initial applications, many 'new' users recognized the added value of 3D data for their own application.
Today, 2D-GIS applications are standard tools in administration and management. As with all state-of-the-art systems certain environmental parameters were found to be difficult to perceive and convey, such that a nove...
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ISBN:
(纸本)9783540721345
Today, 2D-GIS applications are standard tools in administration and management. As with all state-of-the-art systems certain environmental parameters were found to be difficult to perceive and convey, such that a novel 3D-presentation of the environment was developed to be more intuitive. Them cost-effective graphics performance of current computers enables the move towards 3D-GIS and in turn, more detailed views of the environment. While current forestry-2D-GISs provide information on areas or collection of trees., the next generation of forestry-3D-GISs will store and make information available at level of an individual tree. In this paper we introduce an approach to bring vision technology, into the forest. We present a volumetric algorithm based on the, well-known watershed algorithm and use it to detect trees in laser-scanner point-clouds and four-channel aerial views. Based on this data, maps and virtual environments, 'virtual forests' are generated which can be used in a 3D-GIS for forest management, disaster management, forest machine navigation and other purposes.
Simulations of environmental processes are usually modelled by partial differential equations that are approximated with numerical methods, based on regular grids. An attractive alternative for simulating a fluid flow...
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ISBN:
(纸本)9783540721345
Simulations of environmental processes are usually modelled by partial differential equations that are approximated with numerical methods, based on regular grids. An attractive alternative for simulating a fluid flow is the Free-Lagrange Method (FLM). In this paper, I discuss the use of the FLM-based on the Voronoi diagram (VD)-for the modelling of fluid flow in three dimensions (e.g. the movement of underground water or of pollution plumes in the ocean). Such a technique requires the kinetic three-dimensional VD, which is a VD for which the points are allowed to move freely in space. I present a new algorithm for the movement of points in a three-dimensional VD, and show that it can be relatively easy to implement as it is the extension of a simple two-dimensional algorithm.
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