Average credit scores for people in the United States (US) differ from state to state. Some states have high, and some states have low average credit scores. Since lenders and employers use credit scores to make loa...Average credit scores for people in the United States (US) differ from state to state. Some states have high, and some states have low average credit scores. Since lenders and employers use credit scores to make loan and employment decisions, people living in states where average credit scores are high should experience the benefits of living where credit scores tend to allow more favorable loan and employment decisions. Although credit scores are the direct result of credit histories, credit histories may be impacted by demographic factors. If the demographic factors that impact credit histories are identified, ways to improve credit scores are likely to be discovered and available to people and state government policymakers. This study looks for demographic factors to indirectly explain the average credit scores for people living in each state of the US. The methodology includes statistical analyses and geographic information systems (GIS) mapping. Statistical analyses provide evidence to suggest that state average credit scores are explained by the demographic factors of education, family, income, and health. GIS mapping reveals clusters of states with similar demographics and credit scores.展开更多
Over 16 million caregivers of people living with dementia require support in a range of issues, including self-care, disease education, and guidance for how to manage behavioral and psychological symptoms of dementia ...Over 16 million caregivers of people living with dementia require support in a range of issues, including self-care, disease education, and guidance for how to manage behavioral and psychological symptoms of dementia (BPSD). Non-pharmacological interventions are needed to address these areas, and online applications have been shown to be safe and effective. To ensure the efficacy of such interventions, racially, ethnically, geographically, and socioeconomically diverse participants must be recruited to increase the generalizability of study outcomes. This protocol paper describes a recruitment plan using Geographic Information Systems (GIS) to reach a representative sample of caregivers across the United States for a national Phase III clinical study. Using publicly available census data from the American Community Survey (ACS), combined with location data for local aging resources such as Area Agencies on Aging (AAA), recruitment will be derived from data analysis conducted in ESRI ArcGIS v10.7.1. Datasets including age, gender, income, and education will be assessed nationally at the county and census tract spatial scale in a nine-step process to develop recruitment priority areas containing high concentrations of eligible participants living in the community. Overall, the current protocol will demonstrate the value of GIS in tailoring targeted outreach strategies to recruit community-dwelling populations through local resource institutions. This novel approach may have far-reaching implications in future recruitment initiatives and help to secure racially/ethnically diverse samples.展开更多
With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources an...With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System (GIS). This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension (3D) visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology environment about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.展开更多
Yakla area is a very important and typical region in North Tarim, because it is the region that leads to a breakthrough in North Tarim oil/gas exploring. Therefore, a lot of exploration work has been already carried o...Yakla area is a very important and typical region in North Tarim, because it is the region that leads to a breakthrough in North Tarim oil/gas exploring. Therefore, a lot of exploration work has been already carried out in the area aiming at assessing the hydrocarbon anomaly and some techniques for anomaly delineation are being suggested. Yakla covers about 312 km 2 and lies 20 km south to Luntai Kuche road and displays as a long rectangular, with the length of 24 km in ENE and the width of 13 km in WSW. The surface is desert covered with saline akali, sand ribbon and sand dune. Samples collected from Yakla were analyzed for their hydrocarbon mass fractions and the spatial distribution of the concentrations of selected hydrocarbons C 1, C 2, C 3, i C 4, n C 4, i C 5, n C 5 and UF365 were estimated from these data sets. Multivariate statistical techniques including Kriging, moving average, factor analyses, cluster analyses and furrier filtering are used. The statistical techniques, spatial data analysis and transformation capabilities of geographic information systems, combined with geophysical and geological data, helped the authors to identify the hydrocarbon anomaly in Yakla.展开更多
The present study aims to propose the method for the quantitative evaluation of safety concerning evacuation routes in case of earthquake disasters in urban areas using ACO (Ant Colony Optimization) algorithm and G...The present study aims to propose the method for the quantitative evaluation of safety concerning evacuation routes in case of earthquake disasters in urban areas using ACO (Ant Colony Optimization) algorithm and GIS (Geographic Information Systems). Regarding the safety evaluation method, firstly, the similarity in safety was focused on while taking into consideration road blockage probability, and after classifying roads by means of the hierarchical cluster analysis, the congestion rates of evacuation routes using ACO simulations were estimated. Based on these results, the multiple evacuation routes extracted were visualized on digital maps by means of GIS, and its safety was evaluated. Furthermore, the selection of safe evacuation routes between evacuation sites, for cases when the possibility of large-scale evacuation after an earthquake disaster is high, is made possible. As the safety evaluation method is based on public information, by obtaining the same geographic information as the present study, it is effective in other areas regardless of whether the information is of the past and future. Therefore, in addition to spatial reproducibility, the safety evaluation method also has high temporal reproducibility. Because safety evaluations are conducted on evacuation routes based on quantified data, highly safe evacuation routes that are selected have been quantitatively evaluated, and thus serve as an effective indicator when selecting evacuation routes.展开更多
The MARGov Project consisted in strengthening the interaction among the Professor Luiz Saldanha Marine Park stakeholders, and to collaboratively construct, with social and institutional actors, a governance model for ...The MARGov Project consisted in strengthening the interaction among the Professor Luiz Saldanha Marine Park stakeholders, and to collaboratively construct, with social and institutional actors, a governance model for the Marine Park, located in the municipality of Sesimbra (Portugal). To pursue this goal, a PPGIS (public participation geographic information system) was developed, allowing the interaction, discussion and public participation of the stakeholders and actors involved. This PPGIS emerged as a crowdsourcing tool, with the purpose of assisting the georeferenced contributes from the local users of the Marine Park, regarding several relevant subjects, such as pollution, economic activities, opportunities and threats to the Marine Park, providing visual, analytical, and demonstrative qualities.展开更多
The lack of water resources in many regions is the main challenge for the human being and to extended investigations. Water resources controlling and management is essential in the areas depending on the seasonal rain...The lack of water resources in many regions is the main challenge for the human being and to extended investigations. Water resources controlling and management is essential in the areas depending on the seasonal rainfall. This research aims to estimate the surface water runoff for Basin of Alrakhmah Valley located in the southwestern part of Kirkuk Province in northeastern of Iraq. Analyzing of Spatial data and Digital Elevation Model (DEM) data has been conducted using Geographic Information System (GIS) to estimate the hydrological properties for the watershed valley with 158.5 km<sup>2</sup> surface area. The results showed that watershed valley type is from the fifth rank with a longitudinal shape and topography percentage of 0.568. The watershed textures found to be 3.24 and the drain density 1.5 at 3.49 river branching. Finally, the annual estimated surface water retreat according to the morpho-hydro climatic elements found to be 0.01286233 milliard cubic meter.展开更多
Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent im...Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent impetus to computerizing cadastral maps and creating digital cadastral data bases (DCDB). This process is creating many institutional, legal, technical and administrative problems. This desire to establish DCDBs is being given increased impetus due to a new range of enabling technologies such as satellite position fixing (GPS), improved spatial data collection techniques such as digital theodolites and “soft copy” photogrammetry, as well as a vast range of new information and communications technological tools, thus contributing to the advancement and keeping up with the great countries. This paper presents the problem of cadastral maps. The hitherto existing cadastre, consisting of paper maps and land registers, is now becoming insufficient. Its shortcomings force developments leading to its improvement. One of the ways is the creation of a Land Information System. A digital cadastral map is the main component of this system. The structure and information content of the map is presented, its differences from analogue maps are shown, and the process of map creation is described. A digital cadastral map can be the basis for additional thematic layers, successively converting it into a complex system for management of administrative units.展开更多
为了解决工业发展导致的灌区土壤投入品残留污染问题,给出一种基于地理信息系统(geographic information system,GIS)的土壤污染监测预警系统。该系统结合VOC-PF1型传感器、STM32主控芯片和GSM通信模块,实现了高效的数据采集和通信功能...为了解决工业发展导致的灌区土壤投入品残留污染问题,给出一种基于地理信息系统(geographic information system,GIS)的土壤污染监测预警系统。该系统结合VOC-PF1型传感器、STM32主控芯片和GSM通信模块,实现了高效的数据采集和通信功能。通过反距离加权(inverse distance weighted,IDW)插值法进行空间分析,并设立预警阈值,实现对灌区土壤投入品残留污染的实时监测和预警。实验结果表明:该系统的监测精度高达98%,监测时长最高为49 s,具有很高的实用性和效率。研究结果不仅为灌区土壤投入品残留污染监测提供了有效手段,也为环境保护和农业可持续发展提供有力支持。展开更多
Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional ...Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social stability.In recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological security.Based on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was evaluated.The results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.展开更多
This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected b...This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected by this disaster as well as for a reduction of the impact of natural disasters that may occur in the future with GIS (geographic information systems) as a social infrastructure positioned at the heart of the information infrastructure. Due to the fact that social media that used ICT (information and communication technology) was useful in the days directly after the disaster, it can be said that it is necessary to investigate the provision of an information infrastructure that uses ICT to reduce the impact of disasters. Therefore, this study proposes the construction of a geographical information database using GIS and the provision and sharing of information using social media GIS after discussion of the relationship between the development of the computerization of Japan and GIS as a valid example of using information systems for recovery and reconstruction after the Great East Japan Earthquake.展开更多
In this paper, we propose a novel approach to automatically building Informed Virtual Geographic Environments (IVGE) using data provided by Geographic Information Systems (GIS). The obtained IVGE provides 2D and 3D ge...In this paper, we propose a novel approach to automatically building Informed Virtual Geographic Environments (IVGE) using data provided by Geographic Information Systems (GIS). The obtained IVGE provides 2D and 3D geographic information for visualization and simulation purposes. Conventional VGE approaches are generally built upon a grid-based representation, raising the well-known problems of the lack of accuracy of the localized data and the difficulty to merge data with multiple semantics. On the contrary, our approach uses a topological model and provides an exact representation of GIS data, allowing an accurate geometrical exploitation. Moreover, our model can merge semantic information, even if spatially overlapping. In addition, the proposed IVGE contains spatial information which can be enhanced thanks to a geometric abstraction method. We illustrate this model with an application which automatically extracts the required data from standard GIS files and allows a user to navigate and retrieve information from the computed IVGE.展开更多
Yangtze Estuary Tidal Wetlands Geographic Information System (YETWGIS) is a comprehensive software system for environmental management and decision of Yangtze estuary tidal wetlands. Based on MapObjects components tec...Yangtze Estuary Tidal Wetlands Geographic Information System (YETWGIS) is a comprehensive software system for environmental management and decision of Yangtze estuary tidal wetlands. Based on MapObjects components technology, Data Mining technology, mathematical modeling method and Visual Basic language, this software system has many functions such as displaying, editing, querying and searching, spatial statistics and analysis, thematic map compiling, and environmental quality evaluation. This paper firstly outlined the system structure, key techniques, and achieving methods of YETWGIS, and then, described the core modules (the thematic map compiling module and environmental quality evaluation model module) in detail. In addition, based on information entropy model, it thoroughly discussed the methods of environmental quality evaluation and indicators' weight calculation. Finally, by using YETWGIS, this paper analyzed the spatial distribution characteristics of Heavy Metal and Persistent Organic Pollutants (POPs) of the Yangtze estuary tidal wetlands in 2002, and evaluated the environmental quality of the Yangtze estuary tidal wetlands in 2003.展开更多
The human living and developing depend on the land. The remote sensing images in Keerqinhouqi, Inner Mongolia Autonomous Region, China, were processed . Supported by a geographical information system, the image map wa...The human living and developing depend on the land. The remote sensing images in Keerqinhouqi, Inner Mongolia Autonomous Region, China, were processed . Supported by a geographical information system, the image map was formed by th e boundary making and overlaying to the precision-corrected remote sensed image . Finally, the current land use types were also classified and outlined. The area s were also calculated. The error is less than 10 precent, compared with the sur vey. Thus the proceduce is considered accepfable.展开更多
The paper proposes an architectural model of web-based geographic information system based on mashup-technologies. Represented system is designed using the programming patterns and is used to control access rights to ...The paper proposes an architectural model of web-based geographic information system based on mashup-technologies. Represented system is designed using the programming patterns and is used to control access rights to various functions or objects in the system.展开更多
Geographic information system(GIS)technology is a combination of computer’s graphic and database to store and process spatial information.According to the users’ demands,GIS exports the exact geographic information ...Geographic information system(GIS)technology is a combination of computer’s graphic and database to store and process spatial information.According to the users’ demands,GIS exports the exact geographic information and related in- formation for users with map and description through associating geographic place and related attributes.Based on the existing pop- ular technology,this paper presents a distributed web GIS application based on component technology and fractal image compres- sion.It presents the basic framework of the proposed system at first,and then discusses the key technology of implementing this sys- tem;finally it designs a three-layer WEB GIS instance using VC++ATL based on Geo Beans.The example suggests the proposed design is correct,feasible and valid.展开更多
文摘Average credit scores for people in the United States (US) differ from state to state. Some states have high, and some states have low average credit scores. Since lenders and employers use credit scores to make loan and employment decisions, people living in states where average credit scores are high should experience the benefits of living where credit scores tend to allow more favorable loan and employment decisions. Although credit scores are the direct result of credit histories, credit histories may be impacted by demographic factors. If the demographic factors that impact credit histories are identified, ways to improve credit scores are likely to be discovered and available to people and state government policymakers. This study looks for demographic factors to indirectly explain the average credit scores for people living in each state of the US. The methodology includes statistical analyses and geographic information systems (GIS) mapping. Statistical analyses provide evidence to suggest that state average credit scores are explained by the demographic factors of education, family, income, and health. GIS mapping reveals clusters of states with similar demographics and credit scores.
文摘Over 16 million caregivers of people living with dementia require support in a range of issues, including self-care, disease education, and guidance for how to manage behavioral and psychological symptoms of dementia (BPSD). Non-pharmacological interventions are needed to address these areas, and online applications have been shown to be safe and effective. To ensure the efficacy of such interventions, racially, ethnically, geographically, and socioeconomically diverse participants must be recruited to increase the generalizability of study outcomes. This protocol paper describes a recruitment plan using Geographic Information Systems (GIS) to reach a representative sample of caregivers across the United States for a national Phase III clinical study. Using publicly available census data from the American Community Survey (ACS), combined with location data for local aging resources such as Area Agencies on Aging (AAA), recruitment will be derived from data analysis conducted in ESRI ArcGIS v10.7.1. Datasets including age, gender, income, and education will be assessed nationally at the county and census tract spatial scale in a nine-step process to develop recruitment priority areas containing high concentrations of eligible participants living in the community. Overall, the current protocol will demonstrate the value of GIS in tailoring targeted outreach strategies to recruit community-dwelling populations through local resource institutions. This novel approach may have far-reaching implications in future recruitment initiatives and help to secure racially/ethnically diverse samples.
基金The Natural Science Foundation of Xi’an Jiaotong Universitythe China Scholarship Council postgraduate scholarship program under contract No 2007u0307
文摘With the development of modern oceanic observation technologies, coastal survey data have been experiencing a substantial growth. The integration management of the data from different disciplines, different sources and different formats has become a major research field in coastal geomorphology by using Geographic Information System (GIS). This paper puts forward a new methodology framework of GIS techniques in coastal ocean geomorphology, including data acquisition, process, analysis, and representation. It focuses on some major GIS techniques to study the land-ocean interaction mechanism, such as spatial analysis, submarine topography model and three-dimension (3D) visualization, and apply its result to coastal urban planning, harbor site selection and geomorphology environment about coral reef and islands on the continental shelf. The case studies cover the whole coastal ocean to serve the social community, economical development and diplomatic rights for decision-making all round in the coastal zone. The research shows clearly that the application of coastal multi-source geospatial platform has changed the traditional coastal geomorphology science dramatically from its research scope, fields and methods, however, as made clear in this paper, extracting accurate information from remote sensing data and GIS databases for coastal geomorphological applications is a nontrivial challenge that requires the combined knowledge and skills of information scientists and geomorphologists.
文摘Yakla area is a very important and typical region in North Tarim, because it is the region that leads to a breakthrough in North Tarim oil/gas exploring. Therefore, a lot of exploration work has been already carried out in the area aiming at assessing the hydrocarbon anomaly and some techniques for anomaly delineation are being suggested. Yakla covers about 312 km 2 and lies 20 km south to Luntai Kuche road and displays as a long rectangular, with the length of 24 km in ENE and the width of 13 km in WSW. The surface is desert covered with saline akali, sand ribbon and sand dune. Samples collected from Yakla were analyzed for their hydrocarbon mass fractions and the spatial distribution of the concentrations of selected hydrocarbons C 1, C 2, C 3, i C 4, n C 4, i C 5, n C 5 and UF365 were estimated from these data sets. Multivariate statistical techniques including Kriging, moving average, factor analyses, cluster analyses and furrier filtering are used. The statistical techniques, spatial data analysis and transformation capabilities of geographic information systems, combined with geophysical and geological data, helped the authors to identify the hydrocarbon anomaly in Yakla.
文摘The present study aims to propose the method for the quantitative evaluation of safety concerning evacuation routes in case of earthquake disasters in urban areas using ACO (Ant Colony Optimization) algorithm and GIS (Geographic Information Systems). Regarding the safety evaluation method, firstly, the similarity in safety was focused on while taking into consideration road blockage probability, and after classifying roads by means of the hierarchical cluster analysis, the congestion rates of evacuation routes using ACO simulations were estimated. Based on these results, the multiple evacuation routes extracted were visualized on digital maps by means of GIS, and its safety was evaluated. Furthermore, the selection of safe evacuation routes between evacuation sites, for cases when the possibility of large-scale evacuation after an earthquake disaster is high, is made possible. As the safety evaluation method is based on public information, by obtaining the same geographic information as the present study, it is effective in other areas regardless of whether the information is of the past and future. Therefore, in addition to spatial reproducibility, the safety evaluation method also has high temporal reproducibility. Because safety evaluations are conducted on evacuation routes based on quantified data, highly safe evacuation routes that are selected have been quantitatively evaluated, and thus serve as an effective indicator when selecting evacuation routes.
文摘The MARGov Project consisted in strengthening the interaction among the Professor Luiz Saldanha Marine Park stakeholders, and to collaboratively construct, with social and institutional actors, a governance model for the Marine Park, located in the municipality of Sesimbra (Portugal). To pursue this goal, a PPGIS (public participation geographic information system) was developed, allowing the interaction, discussion and public participation of the stakeholders and actors involved. This PPGIS emerged as a crowdsourcing tool, with the purpose of assisting the georeferenced contributes from the local users of the Marine Park, regarding several relevant subjects, such as pollution, economic activities, opportunities and threats to the Marine Park, providing visual, analytical, and demonstrative qualities.
文摘The lack of water resources in many regions is the main challenge for the human being and to extended investigations. Water resources controlling and management is essential in the areas depending on the seasonal rainfall. This research aims to estimate the surface water runoff for Basin of Alrakhmah Valley located in the southwestern part of Kirkuk Province in northeastern of Iraq. Analyzing of Spatial data and Digital Elevation Model (DEM) data has been conducted using Geographic Information System (GIS) to estimate the hydrological properties for the watershed valley with 158.5 km<sup>2</sup> surface area. The results showed that watershed valley type is from the fifth rank with a longitudinal shape and topography percentage of 0.568. The watershed textures found to be 3.24 and the drain density 1.5 at 3.49 river branching. Finally, the annual estimated surface water retreat according to the morpho-hydro climatic elements found to be 0.01286233 milliard cubic meter.
文摘Cadastral maps are an important component of land administration in most countries. In virtually all developed countries, the needs of computerized land and geographic information systems (LIS/GIS) has given urgent impetus to computerizing cadastral maps and creating digital cadastral data bases (DCDB). This process is creating many institutional, legal, technical and administrative problems. This desire to establish DCDBs is being given increased impetus due to a new range of enabling technologies such as satellite position fixing (GPS), improved spatial data collection techniques such as digital theodolites and “soft copy” photogrammetry, as well as a vast range of new information and communications technological tools, thus contributing to the advancement and keeping up with the great countries. This paper presents the problem of cadastral maps. The hitherto existing cadastre, consisting of paper maps and land registers, is now becoming insufficient. Its shortcomings force developments leading to its improvement. One of the ways is the creation of a Land Information System. A digital cadastral map is the main component of this system. The structure and information content of the map is presented, its differences from analogue maps are shown, and the process of map creation is described. A digital cadastral map can be the basis for additional thematic layers, successively converting it into a complex system for management of administrative units.
基金supported by the National Key Technology R&D Program of China under Grant No.2013BAK05B01the National Natural Science Foundation of China under Grant No.41371495+1 种基金the National Grand Fundamental Research 973 Program of China under Grant No.2010CB951102the National Key Technology R&D Program of China under Grant No.2011BAD32B00-04
文摘Ecological security defined as the creation of a condition where the physical surroundings of a community provide for the needs of its inhabitants without diminishing its natural stock,which is important for regional security and social stability.In recent years,land use patterns in the Changbai Mountain region have changed significantly with intensive human activities,and consequently led to increasing problems in regional ecological security.Based on the Pressure-State-Impact-Response(PSIR) model and the mathematical method of catastrophe progression supported by geographical information system(GIS),the ecological security situation of the study area under land use and cover change(LUCC) was evaluated.The results indicated that the ecological security in Changbai Mountain region varied nonlinearly,which got better from 1990 to 2000 but became worse from 2000 to 2007,the ecological security levels in Changbai Mountain region were mainly medium and medium to low during the past 17 years,with higher values of Ecological Security Index(ESI) in the central region and lower values in the east and west,the ecological security situation was more serious in the settlements and river valleys,where the LUCC was most remarkable.
文摘This study considers the regional characteristics of the Tohoku region and the extent of the damage caused by the Great East Japan Earthquake and makes proposals for recovery and reconstruction of the areas affected by this disaster as well as for a reduction of the impact of natural disasters that may occur in the future with GIS (geographic information systems) as a social infrastructure positioned at the heart of the information infrastructure. Due to the fact that social media that used ICT (information and communication technology) was useful in the days directly after the disaster, it can be said that it is necessary to investigate the provision of an information infrastructure that uses ICT to reduce the impact of disasters. Therefore, this study proposes the construction of a geographical information database using GIS and the provision and sharing of information using social media GIS after discussion of the relationship between the development of the computerization of Japan and GIS as a valid example of using information systems for recovery and reconstruction after the Great East Japan Earthquake.
文摘In this paper, we propose a novel approach to automatically building Informed Virtual Geographic Environments (IVGE) using data provided by Geographic Information Systems (GIS). The obtained IVGE provides 2D and 3D geographic information for visualization and simulation purposes. Conventional VGE approaches are generally built upon a grid-based representation, raising the well-known problems of the lack of accuracy of the localized data and the difficulty to merge data with multiple semantics. On the contrary, our approach uses a topological model and provides an exact representation of GIS data, allowing an accurate geometrical exploitation. Moreover, our model can merge semantic information, even if spatially overlapping. In addition, the proposed IVGE contains spatial information which can be enhanced thanks to a geometric abstraction method. We illustrate this model with an application which automatically extracts the required data from standard GIS files and allows a user to navigate and retrieve information from the computed IVGE.
基金National Natural Science Foundation of China No.40131020 No.40173030 Shanghai Science Committee and Environmental Bureau Program Shanghai Basic Science Research Key Program No.02DJ14029 Foundation for the Excellent You
文摘Yangtze Estuary Tidal Wetlands Geographic Information System (YETWGIS) is a comprehensive software system for environmental management and decision of Yangtze estuary tidal wetlands. Based on MapObjects components technology, Data Mining technology, mathematical modeling method and Visual Basic language, this software system has many functions such as displaying, editing, querying and searching, spatial statistics and analysis, thematic map compiling, and environmental quality evaluation. This paper firstly outlined the system structure, key techniques, and achieving methods of YETWGIS, and then, described the core modules (the thematic map compiling module and environmental quality evaluation model module) in detail. In addition, based on information entropy model, it thoroughly discussed the methods of environmental quality evaluation and indicators' weight calculation. Finally, by using YETWGIS, this paper analyzed the spatial distribution characteristics of Heavy Metal and Persistent Organic Pollutants (POPs) of the Yangtze estuary tidal wetlands in 2002, and evaluated the environmental quality of the Yangtze estuary tidal wetlands in 2003.
文摘The human living and developing depend on the land. The remote sensing images in Keerqinhouqi, Inner Mongolia Autonomous Region, China, were processed . Supported by a geographical information system, the image map was formed by th e boundary making and overlaying to the precision-corrected remote sensed image . Finally, the current land use types were also classified and outlined. The area s were also calculated. The error is less than 10 precent, compared with the sur vey. Thus the proceduce is considered accepfable.
文摘The paper proposes an architectural model of web-based geographic information system based on mashup-technologies. Represented system is designed using the programming patterns and is used to control access rights to various functions or objects in the system.
文摘Geographic information system(GIS)technology is a combination of computer’s graphic and database to store and process spatial information.According to the users’ demands,GIS exports the exact geographic information and related in- formation for users with map and description through associating geographic place and related attributes.Based on the existing pop- ular technology,this paper presents a distributed web GIS application based on component technology and fractal image compres- sion.It presents the basic framework of the proposed system at first,and then discusses the key technology of implementing this sys- tem;finally it designs a three-layer WEB GIS instance using VC++ATL based on Geo Beans.The example suggests the proposed design is correct,feasible and valid.