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GEOSENSING SYSTEMS ENGINEERING FOR OCEAN SECURITY AND SUSTAINABLE COASTAL ZONE MANAGEMENT

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Journal of Systems Science and Systems Engineering 2010年第1期19卷 22-35页

作者： Hamid ASSILZADEH Jason K. LEVY Xin WANG Yang GAO Zhinong ZHONG Department of Geomaties Engineering University of Calgary Calgary Alberta Canada L. Douglas Wilder School of Government and Public Affairs Virginia Commonwealth University Department of Geomatics Engineering University of Calgary Calgary Alberta Canada School of Electronic Science and Engineering National University of Defense Technology Changsha China

Three major threats to ocean security and coastal zone sustainability - global warming, the loss of ocean biodiversity, and pollution - are combining to threaten the ecological integrity of our marine environment and life support systems. We put forward a geomatics-based systems engineering architecture to identify the location and extent of oil spills, thereby improving the ecological integrity of the world＇s oceans and helping contingency planners to determine required assets, personnel and other resources. This real-time, event-based and cost effective emergency management decision support system can aid in the classification, detection, and monitoring of oil spills in the marine environment. The developed Synthetic-Aperture Radar （SAR） processing and calibration techniques efficiently monitor environmental changes in inaccessible ocean regions, characterize oil spill scenarios, and help to identify spill sources. The system is used to improve emergency management in the Gulf of Mexico, with application to oil spills arising from Hurricane Katrina.

关键词： Ocean security geosensing systems engineering coastal zone management SAR

DEM Fusion using a modified k-means clustering algorithm

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International Journal of Digital Earth 2016年第12期9卷 1242-1255页

作者： Colleen E.Fuss Aaron A.Berg John B.Lindsay Department of Geography University of GuelphGuelphCanada

Digital elevation models(DEMs)are a necessary dataset for modelling the Earth’s surface;however,all DEMs contain *** can reduce this error using DEM fusion techniques since numerous DEMs can be available for a ***,the use of a clustering algorithm in DEM fusion has not been previously *** this study a new DEM fusion algorithm based on a clustering approach that works on multiple DEMs to exploit consistency in the estimates as indicators of accuracy and precision is *** fusion approach includes slope and elevation thresholding,k-means clustering of the elevation estimates at each cell location,as well as filtering and smoothing of the fusion *** of the input DEMs,and the products of each step of the fusion algorithm,with a higher accuracy reference DEM enabled a detailed analysis of the effectiveness of the DEM fusion *** main findings of the research were:the k-means clustering of the elevations reduced the precision which also impacted the overall accuracy of the estimates;the number of final cluster members and the standard deviation of elevations before clustering both had a strong relationship to the error in the k-means estimates.

关键词： DEM fusion k-means clustering DEM error

Abstraction of informed virtual geographic environments

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Geo-Spatial Information Science 2012年第1期15卷 27-36页

作者： Mehdi MEKNI Eau Terre Environnement Center Institut National de Recherche Scientifique(INRS)Quebec CityCanada G1K 9A9

We propose a novel method for the automated generation of virtual geographic environments that allows using geographic information system data to build what we call informed virtual geographic environment(IVGE).The description of an IVGE integrates semantic information expressed using conceptual graphs,a standard knowledge representation *** addition,we propose an abstraction process that uses geometric,topologic,and semantic characteristics of geographic features to build a hierarchical graph-based structure describing this *** IVGE model enables the support of large-scale and complex geographic environment modeling for multiagent geo-simulations in which the agents are situated and with which they interact.

关键词： GIS informed virtual geographic environment(IVGE) abstraction process semantic information

Characterization of spatial relationships between three remotely sensed indirect indicators of biodiversity and climate:a 21years’data series review across the Canadian boreal forest

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International Journal of Digital Earth 2016年第7期9卷 676-696页

作者： Liliana Perez Trisalyn Nelson Nicholas C.Coops Fabio Fontana C.Ronnie Drever Laboratory of Environmental Geosimulation(LEDGE) Department of GeographyUniversity of MontrealMontrealQCCanada Spatial Pattern Analysis&Research(SPAR)Lab Department of GeographyUniversity of VictoriaVictoriaBCCanada Department of Forest Resources Management University of British ColumbiaVancouverBCCanada The Nature Conservancy OttawaONCanada

Climate drives ecosystem processes and impacts *** patterns over large areas,such as Canada’s boreal,can be monitored using indirect indicators derived from remotely sensed *** this paper,we characterized the historical space–time relationships between climate and a suite of indirect indicators of biodiversity,known as the Dynamic Habitat Index(DHI)to identify where climate variability is co-occurring with changes in biodiversity *** represented biodiversity using three indirect indicators generated from 1987 to 2007 National Oceanic and Atmospheric Administration Advanced Very High Resolution Radiometer *** quantifying and clustering temporal variability in climate data,we defined eight homogeneous climate variability zones,where we then analyzed the *** identified unique areas of change in climate,such as the Hudson Plains,that explain significant variations in *** variability in temperatures and growing season index had a strong influence on observed vegetation productivity and seasonality changes throughout Canada’s *** in precipitation,for most of the area,was not associated with DHI *** methodology presented here enables assessment of spatial–temporal relationships between biodiversity and climate variability and characterizes distinctive zones of variation that may be used for prioritization and planning to ensure long-term biodiversity conservation in Canada.

关键词： Climate change biodiversity boreal forest spatial–temporal analysis fPAR DHI

最小二乘谱及其在超导重力观测数据分析中的应用

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武汉大学学报（信息科学版） 2005年第7期30卷 613-616页

作者：尹晖 Spiros D.Pagiatakis 武汉大学测绘学院武汉市珞喻路129号430079 约克大学地球与空间科学和工程系

运用投影理论和基于向量空间中最小二乘平差原理,介绍了最小二乘谱分析方法,给出了最小二乘谱的计算公式。利用加拿大超导重力观测数据实例,讨论了最小二乘谱分析的策略和步骤。

关键词：最小二乘谱超导重力仪数据分析