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Suphanut Jamonnak Shamal Al-Dohuki Xinyue Ye Farah Kamw 《International journal of geographical information science》2020,34(11):2115-2135
ABSTRACT Videos embedded with spatial coordinates, especially when combined with additional expert insights, offer the potential to acquire fine-scale multi-time period contextualized data for a variety of different environments. However, while these geospatial multimedia (GSMM) data include abundant spatiotemporal, semantic and visual information, the means to fully leverage their potential using a suite of visual and interactive analysis techniques and tools has thus far been lacking. In this paper, we address this gap by first identifying the types of tasks required of GSMM data, and then presenting a solution platform. This GeoVisuals system utilizes a visual analysis approach built on semantic data points that can be integrated spatially, which in turn enables management in a unified database with combined spatio-temporal and text querying. A set of visualization functions are integrated in two investigation modes: geo-video analysis and geo-location analysis. 相似文献
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We apply geospatial analysis to borehole imagery in an effort to develop new techniques to evaluate the spatial distribution and internal structure of karst conduits. Remote sensing software is used to classify a high resolution, digital borehole image of limestone bedrock from the Biscayne aquifer (South Florida, USA) into a binary image divided into cells of rock matrix and pores. Within a GIS, 2D porosity is calculated for a series of rectangular sampling windows placed over the binary image and then plotted as a function of depth. Potential conduits that intersect the borehole are identified as peaks of high porosity. A second GIS technique identifies a conduit as a continuous object that spans the entire borehole width. According to these criteria, geospatial analysis reveals ∼10 discrete conduits along the ∼15 m borehole image. Continuous sampling of the geologic medium intersected by the borehole provides insight into the internal structure of karst aquifers and the evolution of karst features. Most importantly, this pilot study demonstrates that GIS-based techniques are capable of quantifying the depths, dimensions, shapes, apertures and connectivity of potential conduits, physical attributes that impact flow in karst aquifers. 相似文献
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Aarthy Sabesan Kathleen Abercrombie Auroop R. Ganguly Budhendra Bhaduri Eddie A. Bright Phillip R. Coleman 《GeoJournal》2007,69(1-2):81-91
Geospatial data sciences have emerged as critical requirements for high-priority application solutions in diverse areas, including,
but not limited to, the mitigation of natural and man-made disasters. Three sets of metrics, adopted or customized from geo-statistics,
applied meteorology and signal processing, are tested in terms of their ability to evaluate geospatial datasets, specifically
two population databases commonly used for disaster preparedness and consequence management. The two high-resolution, grid-based
population datasets are the following: The LandScan dataset available from the Geographic Information Science and Technology
(GIST) group at the Oak Ridge National Laboratory (ORNL), and the Gridded Population of the World (GPW) dataset available
from the Center for International Earth Science Information Network (CIESIN) group at Columbia University. Case studies evaluate
population data across the globe, specifically, the metropolitan areas of Washington DC, USA, Los-Angeles, USA, and Houston,
USA, and London, UK, as well as the country of Iran. The geospatial metrics confirm that the two population datasets have
significant differences, especially in the context of their utility for disaster readiness and mitigation. While this paper
primarily focuses on grid based population datasets and disaster management applications, the sets of metrics developed here
can be generalized to other geospatial datasets and applications. Future research needs to develop metrics for geospatial
and temporal risks and associated uncertainties in the context of disaster management.
The U. S. Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged. 相似文献
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国土资源空间数据共享模式研究 总被引：1，自引：0，他引：1
本文分析了空间数共享的四种主要模式,指出基于图片的空间数据快速浏览模式是目前一种有效的空间数据共享模式,并介绍了应用该模式的国土资源空间数据快速浏览系统。 相似文献
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Measuring similarity between geospatial lifelines in studies of environmental health 总被引：3，自引：0，他引：3
Many epidemiological studies involve analysis of clusters of diseases to infer locations of environmental hazards that could be responsible for the disease. This approach is however only suitable for sedentary populations or diseases with small latency periods. For migratory populations and diseases with long latency periods, people may change their residential location between time of exposure and onset of ill health. For such situations, clusters are diffused and diluted by in- and out-migration and may become very difficult to detect. One way to address the problem of diffused clusters is to include in analyses not only current residential locations, but all past locations at which cases might have been exposed to environmental hazardous. In this paper, we assume that a persons residential history provides such information and represent it through a discrete geospatial lifeline data model. Clusters of similar geospatial lifelines represent individuals who have similar residential histories—and therefore represent people who are more likely to have had similar environmental exposure histories. We therefore introduce a lifeline distance (dissimilarity) measure to detect clusters of cases, providing a basis for revealing possible regions in space-time where environmental hazards might have existed in the past. The ability of the measure to distinguish cases from controls is tested using two sets of synthetically generated cases and controls. Results indicate that the measure is able to consistently distinguish between populations of cases and controls with statistically significant results. The lifeline distance measure consistently outperforms another measure which uses only the distance between subjects residences at time of diagnosis. However, the advantages of using the entire residential history are only partly realized, since the ability to distinguish between cases and controls is only moderately better for the lifeline distance function. Future work is needed to investigate modifications to the inter-lifeline distance measure in order to enhance the potential of this approach to detect locations of environmental hazards over the lifespan.This project is supported by grant number 1 R01 ES09816-01 from the National Institute of Environmental Health Sciences, NIH. Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the NIEHS or NIH. We wish to thank Peter Rogerson for helpful discussions of the migration models, and the anonymous reviewers for pointing out areas where the paper could be improved. 相似文献
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地理空间元数据管理的研究与实现 总被引：1，自引：0，他引：1
论述了地理空间元数据的基本概念 ,分析了地理空间元数据管理面临的困难和挑战 ;通过介绍国产GIS基础软件“吉奥之星”中地理空间元数据管理模块的实现 ,进一步论述了地理空间元数据管理的有关问题 ;最后提出了一种在国家地理空间数据交换中心的地理空间元数据管理模型。 相似文献
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Julia Wagemann Oliver Clements Ramiro Marco Figuera Angelo Pio Rossi Simone Mantovani 《International Journal of Digital Earth》2018,11(1):7-25
ABSTRACTBig Earth Data has experienced a considerable increase in volume in recent years due to improved sensing technologies and improvement of numerical-weather prediction models. The traditional geospatial data analysis workflow hinders the use of large volumes of geospatial data due to limited disc space and computing capacity. Geospatial web service technologies bring new opportunities to access large volumes of Big Earth Data via the Internet and to process them at server-side. Four practical examples are presented from the marine, climate, planetary and earth observation science communities to show how the standard interface Web Coverage Service and its processing extension can be integrated into the traditional geospatial data workflow. Web service technologies offer a time- and cost-effective way to access multi-dimensional data in a user-tailored format and allow for rapid application development or time-series extraction. Data transport is minimised and enhanced processing capabilities are offered. More research is required to investigate web service implementations in an operational mode and large data centres have to become more progressive towards the adoption of geo-data standard interfaces. At the same time, data users have to become aware of the advantages of web services and be trained how to benefit from them most. 相似文献