This document describes the creation of an informative Web GIS aimed at mitigating the impacts of flooding in the municipality of Ouagadougou, in Burkina Faso, a region that is highly sensitive to climate change. Burk...This document describes the creation of an informative Web GIS aimed at mitigating the impacts of flooding in the municipality of Ouagadougou, in Burkina Faso, a region that is highly sensitive to climate change. Burkina Faso, which is undergoing rapid urbanization, faces major natural threats, particularly flooding, as demonstrated by the severe floods of 2009 that caused loss of life, injury, structural damage and economic losses in Ouagadougou. The aim of this research is to develop a web map highlighting the municipality’s flood-prone areas, with a view to informing and raising awareness of flood risk reduction. Using the Leaflet JavaScript mapping library, the study uses HTML, CSS and JavaScript to implement web mapping technology. Data on Ouagadougou’s flood zones is generated by a multi-criteria analysis combining Saaty’s AHP method and GIS in QGIS, integrating seven (7) parameters including hydrography, altitude, slope, rainfall, soil types, land use and soil moisture index. QGIS processes and maps the themes, PostgreSQL with PostGIS serves as the DBMS and GeoServer functions as the map server. The Web GIS platform allows users to visualize the different flood risks, from very low to very high, or the high-risk areas specific to Ouagadougou. The AHP calculations classify the municipality into five flood vulnerability zones: very low (24.48%), low (27.93%), medium (23.01%), high (17.11%) and very high (7.47%). Effective risk management requires communication and awareness-raising. This online mapping application serves as a tool for communication, management and flood prevention in Ouagadougou, helping to mitigate flood-related natural disasters.展开更多
探索将万维网地理信息系统(Web Geographic Information System,WebGIS)技术引入数字无线电广播发射覆盖分析领域,重点研究数据处理、平台搭建、模型构建及可视化分析等关键技术环节,并探讨覆盖优化调整的策略与方法。通过构建高精度数...探索将万维网地理信息系统(Web Geographic Information System,WebGIS)技术引入数字无线电广播发射覆盖分析领域,重点研究数据处理、平台搭建、模型构建及可视化分析等关键技术环节,并探讨覆盖优化调整的策略与方法。通过构建高精度数据集、搭建高效WebGIS平台、改进传播模型、开发可视化分析工具等手段,力图为无线电广播网络的精细化规划和智能化管理提供新的思路和方法。展开更多
The multi-granularity spatial-temporal-related access control（MSTAC） model was proposed to meet the spatial access control requirements for the service-oriented spatial data infrastructure（SDI）. MSTAC extends the ...The multi-granularity spatial-temporal-related access control（MSTAC） model was proposed to meet the spatial access control requirements for the service-oriented spatial data infrastructure（SDI）. MSTAC extends the attribute constraints of role-based access control（RBAC）, which includes the user＇s location attribute, the role＇s time constraint, the layer vector constraint of a map class, the scale and time constraints of a geographic layer, the topological constraints of geographic features, the semantic attribute expression constraints of geographic features, and the field constraint of feature views. Through this model, authorized users would be limited to access different granularity spatial datasets, such as the map granularity, the graphic layer granularity, the feature object granularity and the feature view granularity. Finally, the MSTAC model is achieved in a web GIS, which shows the positive and negative authorizations to different services in different data granularities and time periods.展开更多
Recent advancements in internet mapping technology, efficient geospatial data management systems, and availability of different GIS API’s have revolutionized the way in which the geospatial data is being used, shared...Recent advancements in internet mapping technology, efficient geospatial data management systems, and availability of different GIS API’s have revolutionized the way in which the geospatial data is being used, shared and represented through distributed systems for business applications. However, development of powerful, highly functional, yet cost- and time-effective enterprise WebGIS business systems requires a very robust and highly scalable architecture. The architecture should have the inherent characteristics of rapid development, a well-defined object library and at the same time it should comply with the existing geospatial interoperability standards defined by Open Geospatial Consortium (OGC). On the other hand, development of extendible distributed business GIS systems requires the presence of tailor-made inbuilt models available as modules which can be extended further by readily implementable user-interface templates supported by object modeling environment which allows for custom design and delivery of the processes and map output. There are various commercial and open source web mapping solutions which offer a great deal of flexibility and functionality. Nevertheless, they restrict the user community with certain limitations, in terms of functionality, cost or complexity. This necessitates, defining a new approach which efficiently caters the user requirements and not limiting them with aforementioned shortcomings. This paper aims to evaluate various architectural alternatives for delivering robust?distributed GIS business solutions and also attempts to give an account of an implementable instance of a WebGIS architecture which can cater the multi-user and multi-industry requirements.展开更多
文摘This document describes the creation of an informative Web GIS aimed at mitigating the impacts of flooding in the municipality of Ouagadougou, in Burkina Faso, a region that is highly sensitive to climate change. Burkina Faso, which is undergoing rapid urbanization, faces major natural threats, particularly flooding, as demonstrated by the severe floods of 2009 that caused loss of life, injury, structural damage and economic losses in Ouagadougou. The aim of this research is to develop a web map highlighting the municipality’s flood-prone areas, with a view to informing and raising awareness of flood risk reduction. Using the Leaflet JavaScript mapping library, the study uses HTML, CSS and JavaScript to implement web mapping technology. Data on Ouagadougou’s flood zones is generated by a multi-criteria analysis combining Saaty’s AHP method and GIS in QGIS, integrating seven (7) parameters including hydrography, altitude, slope, rainfall, soil types, land use and soil moisture index. QGIS processes and maps the themes, PostgreSQL with PostGIS serves as the DBMS and GeoServer functions as the map server. The Web GIS platform allows users to visualize the different flood risks, from very low to very high, or the high-risk areas specific to Ouagadougou. The AHP calculations classify the municipality into five flood vulnerability zones: very low (24.48%), low (27.93%), medium (23.01%), high (17.11%) and very high (7.47%). Effective risk management requires communication and awareness-raising. This online mapping application serves as a tool for communication, management and flood prevention in Ouagadougou, helping to mitigate flood-related natural disasters.
文摘探索将万维网地理信息系统(Web Geographic Information System,WebGIS)技术引入数字无线电广播发射覆盖分析领域,重点研究数据处理、平台搭建、模型构建及可视化分析等关键技术环节,并探讨覆盖优化调整的策略与方法。通过构建高精度数据集、搭建高效WebGIS平台、改进传播模型、开发可视化分析工具等手段,力图为无线电广播网络的精细化规划和智能化管理提供新的思路和方法。
基金Projects(41074010,41171343)supported by the National Natural Science Foundation of ChinaProject(BK20140185)supported by Jiangsu Province Natural Science Foundation for Youths,China+1 种基金Project(51204185)supported by National Youth Science Foundation of ChinaProject(2014QNA44)supported by Youth Science Fund of China University of Mining and Technology
文摘The multi-granularity spatial-temporal-related access control（MSTAC） model was proposed to meet the spatial access control requirements for the service-oriented spatial data infrastructure（SDI）. MSTAC extends the attribute constraints of role-based access control（RBAC）, which includes the user＇s location attribute, the role＇s time constraint, the layer vector constraint of a map class, the scale and time constraints of a geographic layer, the topological constraints of geographic features, the semantic attribute expression constraints of geographic features, and the field constraint of feature views. Through this model, authorized users would be limited to access different granularity spatial datasets, such as the map granularity, the graphic layer granularity, the feature object granularity and the feature view granularity. Finally, the MSTAC model is achieved in a web GIS, which shows the positive and negative authorizations to different services in different data granularities and time periods.
文摘Recent advancements in internet mapping technology, efficient geospatial data management systems, and availability of different GIS API’s have revolutionized the way in which the geospatial data is being used, shared and represented through distributed systems for business applications. However, development of powerful, highly functional, yet cost- and time-effective enterprise WebGIS business systems requires a very robust and highly scalable architecture. The architecture should have the inherent characteristics of rapid development, a well-defined object library and at the same time it should comply with the existing geospatial interoperability standards defined by Open Geospatial Consortium (OGC). On the other hand, development of extendible distributed business GIS systems requires the presence of tailor-made inbuilt models available as modules which can be extended further by readily implementable user-interface templates supported by object modeling environment which allows for custom design and delivery of the processes and map output. There are various commercial and open source web mapping solutions which offer a great deal of flexibility and functionality. Nevertheless, they restrict the user community with certain limitations, in terms of functionality, cost or complexity. This necessitates, defining a new approach which efficiently caters the user requirements and not limiting them with aforementioned shortcomings. This paper aims to evaluate various architectural alternatives for delivering robust?distributed GIS business solutions and also attempts to give an account of an implementable instance of a WebGIS architecture which can cater the multi-user and multi-industry requirements.
