We present a higher-order approach to the extraction of isosurfaces from unstructured meshes. Existing methods use linear interpolation along each mesh edge to find isosurface intersections. In contrast, our method de...
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Sustainable forest management requires new tools to analyze spatial and temporal forest dynamics and to examine those forest parameters that are related to sustainability. We built a prototype system for dataanalysis...
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Sustainable forest management requires new tools to analyze spatial and temporal forest dynamics and to examine those forest parameters that are related to sustainability. We built a prototype system for dataanalysis and decision-making at forest enterprise level by integrating a forest ecosystem model EFIMOD-PRO, (long-term prediction of forest growth and soil development) with an interactive visualization system CommonGIS for analysis of spatially and temporally related data. Using the prototype, a case study in Central European Russia simulated four silvicultural regimes over 200 years: natural development, selective forestry, legal forestry according to the Russian forestry legislation, and illegal forest practice. Exploratory analysis of the simulation results demonstrated that (1) natural stand development is the best alternative for carbon sequestration;(2) legal forest management is the best regime for timber production;(3). selective forestry combines the advantages of two previous strategies, and can be the best strategy for implementing sustainable forest management;and (4) illegal forest practices lead to a fast decrease in forest productivity and decreasing biodiversity. Interactive and dynamic visualizations With maps and statistical graphics played a crucial role in data cleaning, model validation, and analysis of simulation results. The case study demonstrated the potential of integrating forest ecosystem models with exploratory datavisualization for the analysis and expert evaluation at the local level. The prototype can be used to present ecological and silvicultural consequences of various management practices to stakeholders and differing social groups, thus stimulating effective decision-making for sustainable forestry. (c) 2005 Elsevier B.V. All rights reserved.
We present a web-based system to monitor the quality of the meta-data used to describe content in web portals. The system implements meta-dataanalysis using statistical, visualization and data mining tools. The web-b...
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ISBN:
(纸本)9780769527499
We present a web-based system to monitor the quality of the meta-data used to describe content in web portals. The system implements meta-dataanalysis using statistical, visualization and data mining tools. The web-based system enables the site's editor to detect and correct problems in the description of contents, thus improving the quality of the web portal and the satisfaction of its users. We have developed this system and tested it on a Portuguese portal for management executives.
Unrestricted access to both historical and archaeological sites is highly desirable from both a research and a cultural perspective. With the recent developments in 3D scanner technologies and photogrammetric techniqu...
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Unrestricted access to both historical and archaeological sites is highly desirable from both a research and a cultural perspective. With the recent developments in 3D scanner technologies and photogrammetric techniques, it is now possible to acquire and create accurate models of such sites. Through the process of virtualisation, numerous 3D collections are created that need to be visualised, indexed and eventually characterized. This paper presents a mobile virtual environment designed for the visualization of photorealistic high-resolution virtualised cultural heritage scenes and artefacts. In addition, it is shown how it is possible to describe and index the texture and the 3D shape of these artefacts with compact support feature vectors. A data mining system, based on these vectors, allows the characterization and the exploration of the 3D collections, through cluster analysis.
This paper presents a joint effort to make huge event traces accessible for interactive program analysis. It combines a distributed software architecture with compressible data structures and customized query algorith...
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ISBN:
(纸本)0769522807
This paper presents a joint effort to make huge event traces accessible for interactive program analysis. It combines a distributed software architecture with compressible data structures and customized query algorithms. The advanced technologies are discussed both theoretically and practically. Based on a proof-of-concept implementation the response times for typical queries are presented to show the practical relevance of this combined approach.
Systems on board spacecraft have since long manifested their weakness towards the violence of space weather conditions and events. At the European Space Operations Centre, the first step in what concerns the provision...
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In this paper we propose a novel method for learning a Mahalanobis distance measure to be used in the KNN classification algorithm. The algorithm directly maximizes a stochastic variant of the leave-one-out KNN score ...
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ISBN:
(纸本)0262195348
In this paper we propose a novel method for learning a Mahalanobis distance measure to be used in the KNN classification algorithm. The algorithm directly maximizes a stochastic variant of the leave-one-out KNN score on the training set. It can also learn a low-dimensional linear embedding of labeled data that can be used for datavisualization and fast classification. Unlike other methods, our classification model is non-parametric, making no assumptions about the shape of the class distributions or the boundaries between them. The performance of the method is demonstrated on several data sets, both for metric learning and linear dimensionality reduction.
Renderings of volumetric data have become an important dataanalysis tool for applications ranging from medicine to scientific simulation. We propose a volumetric drawing system that directly extracts sparse linear fe...
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Renderings of volumetric data have become an important dataanalysis tool for applications ranging from medicine to scientific simulation. We propose a volumetric drawing system that directly extracts sparse linear features, such as silhouettes and suggestive contours, using a temporally coherent seed-and-traverse framework. In contrast to previous methods based on isosurfaces or nonrefractive transparency, producing these drawings requires examining an asymptotically smaller subset of the data, leading to efficiency on large data sets. In addition, the resulting imagery is often more comprehensible than standard rendering styles, since it focuses attention on important features in the data. We test our algorithms on datasets up to 512(3), demonstrating interactive extraction and rendering of line drawings in a variety of drawing styles.
A survey of the ATLAS environment, a tool for the simulation of nuclear power plants and reactor safety analyses, is presented. The basic configuration, including a wide spectrum of simulation models, the interactive ...
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A survey of the ATLAS environment, a tool for the simulation of nuclear power plants and reactor safety analyses, is presented. The basic configuration, including a wide spectrum of simulation models, the interactive visualization system and a data server, is described. The modelling capabilities comprise general fluiddynamics and thermal-hydraulics, core damage, neutron dynamic models and the containment models for the pressurization and fission product behaviour. The visualization provides interactive process diagrams that may be designed by a graphic editor. A 3D-visualization tool is also integrated. Several analysis support tools are added for extended safety studies. Uncertainty analyses, operational procedure simulation and a leak estimation system are explained in more detail. Examples for the application of ATLAS in detailed plant specific analysis simulators, in the training of severe accident phenomena and for human factor analyses are given. The present development is focused on transient recognition and the increase of the simulation speed of the models.
The proceedings contain 135 papers and 1 PowerPoint presentation. The topics discussed include: discovering biostructure constraints using VRML visualization;multi-scale and multi-physics visualization;modeling the fl...
The proceedings contain 135 papers and 1 PowerPoint presentation. The topics discussed include: discovering biostructure constraints using VRML visualization;multi-scale and multi-physics visualization;modeling the fluffy lens: construction of the virtual chinchilla;an explorational exhibit of a pig's heart;robust automatic optic disk segmentation;3-D cancer cell visualization for patients and scientists;emphasizing the area of interest using real-time shaders;visualization of large ISO-surfaces based on nested clip-boxes;using 3D visualization to enhance understanding of computer network state;automatic cross-sectioning using 3D field topology analysis;particles with a history - visualizing flow fields with GPU-based streamlines;advanced datavisualization on 3D accelerated PDA's;a 3D graphics toolkit for studying neural basis of adaptive behaviors;a partial shape matching technique for 3D model retrieval systems;and realtime loop subdivision on the GPU.
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