针对空间信息网络服务在现有C/S、B/S模式下客户端功能的不足和空间数据服务需求,采用一种新型的空间信息服务模式--G/S模式,即地学浏览器/空间信息服务器模式,并对其可视化客户端G端地学浏览器(Geo-Browser)的系统架构和关键技术进行...针对空间信息网络服务在现有C/S、B/S模式下客户端功能的不足和空间数据服务需求,采用一种新型的空间信息服务模式--G/S模式,即地学浏览器/空间信息服务器模式,并对其可视化客户端G端地学浏览器(Geo-Browser)的系统架构和关键技术进行详细论述。利用Google Earth COM API组件开发技术,在国际标准KML支持下,对地学浏览器进行详细设计和实例验证,得出G/S模式下的地学浏览器在海量空间信息处理和三维展示方面具有明显优势的结论。展开更多
为了研究G/S(geographic information browser/distributed spatial data servers)模式客户端动态聚合服务,提出了一种在Android系统下基于G/S模式的地理信息浏览器缓存技术。利用移动终端硬件与软件技术的发展优势,将缓存结构分为3部分...为了研究G/S(geographic information browser/distributed spatial data servers)模式客户端动态聚合服务,提出了一种在Android系统下基于G/S模式的地理信息浏览器缓存技术。利用移动终端硬件与软件技术的发展优势,将缓存结构分为3部分:用于存储显示地图瓦片的显示缓存,用于预存取的预存取缓存和由SQLite数据库管理的外部缓存。测试结果表明,该技术在提高地图瓦片加载速度的同时消除了移动终端在访问空间数据时的网络瓶颈。展开更多
Conventional, grid-based sampling location tracking approach with GPS or topographic maps is time-consuming and inconvenient. Therefore, this study combined the freely available virtual/digital globe with recent advan...Conventional, grid-based sampling location tracking approach with GPS or topographic maps is time-consuming and inconvenient. Therefore, this study combined the freely available virtual/digital globe with recent advancements of smartphone geo-browsers to develop a new sampling location tracking approach. The sampling frame was developed with pre-uploaded point map formulated in GIS environment by combining land-use map and one-kilometer grid with center coordinates. The sampling location grid was uploaded to smartphone and each point was tracked with Google Map path finder using point ID (coded grid coordinate) when searching each sampling location. The suitability of the new approach was tested for soil sample collection from paddy lands distributed in 0.9 million hectares in Sri Lanka. The sampling locations could be reached conveniently with the help of Google path-finder voice direction guide and optional routes. The efficiency of new approach was found to be remarkably high, <em>i.e</em>., over 99% of the 9000 sampling points, which were spread across Sri Lanka having an area of 65,610 km<sup>2</sup>. All sampling points in the country could be covered with twelve member field investigation crew who were guided through smartphones uploaded with sampling point grid on six motorbikes within 60 days. The new sampling location tracking approach is effective in terms of cost, time, human resource requirements, thus can be adopted in large-scale soil/plant sampling frames with high accuracy.展开更多
Several innovative‘participatory sensing’initiatives are under way in East Africa.They can be seen as local manifestations of the global notion of Digital Earth.The initiatives aim to amplify the voice of ordinary c...Several innovative‘participatory sensing’initiatives are under way in East Africa.They can be seen as local manifestations of the global notion of Digital Earth.The initiatives aim to amplify the voice of ordinary citizens,improve citizens’capacity to directly influence public service delivery and hold local government accountable.The popularity of these innovations is,among other things,a local reaction to the partial failure of the millennium development goals(MDGs)to deliver accurate statistics on public services in Africa.Empowered citizens,with access to standard mobile phones,can‘sense’via text messages and report failures in the delivery of local government services.The public disclosure of these reports on the web and other mass media may pressure local authorities to take remedial action.In this paper,we outline the potential and research challenges of a‘participatory sensing’platform,which we call a‘human sensor web.’Digital Africa’s first priority could be to harness continent-wide and national data as well as local information resources,collected by citizens,in order to monitor,measure and forecast MDGs.展开更多
文摘针对空间信息网络服务在现有C/S、B/S模式下客户端功能的不足和空间数据服务需求,采用一种新型的空间信息服务模式--G/S模式,即地学浏览器/空间信息服务器模式,并对其可视化客户端G端地学浏览器(Geo-Browser)的系统架构和关键技术进行详细论述。利用Google Earth COM API组件开发技术,在国际标准KML支持下,对地学浏览器进行详细设计和实例验证,得出G/S模式下的地学浏览器在海量空间信息处理和三维展示方面具有明显优势的结论。
文摘为了研究G/S(geographic information browser/distributed spatial data servers)模式客户端动态聚合服务,提出了一种在Android系统下基于G/S模式的地理信息浏览器缓存技术。利用移动终端硬件与软件技术的发展优势,将缓存结构分为3部分:用于存储显示地图瓦片的显示缓存,用于预存取的预存取缓存和由SQLite数据库管理的外部缓存。测试结果表明,该技术在提高地图瓦片加载速度的同时消除了移动终端在访问空间数据时的网络瓶颈。
文摘Conventional, grid-based sampling location tracking approach with GPS or topographic maps is time-consuming and inconvenient. Therefore, this study combined the freely available virtual/digital globe with recent advancements of smartphone geo-browsers to develop a new sampling location tracking approach. The sampling frame was developed with pre-uploaded point map formulated in GIS environment by combining land-use map and one-kilometer grid with center coordinates. The sampling location grid was uploaded to smartphone and each point was tracked with Google Map path finder using point ID (coded grid coordinate) when searching each sampling location. The suitability of the new approach was tested for soil sample collection from paddy lands distributed in 0.9 million hectares in Sri Lanka. The sampling locations could be reached conveniently with the help of Google path-finder voice direction guide and optional routes. The efficiency of new approach was found to be remarkably high, <em>i.e</em>., over 99% of the 9000 sampling points, which were spread across Sri Lanka having an area of 65,610 km<sup>2</sup>. All sampling points in the country could be covered with twelve member field investigation crew who were guided through smartphones uploaded with sampling point grid on six motorbikes within 60 days. The new sampling location tracking approach is effective in terms of cost, time, human resource requirements, thus can be adopted in large-scale soil/plant sampling frames with high accuracy.
文摘Several innovative‘participatory sensing’initiatives are under way in East Africa.They can be seen as local manifestations of the global notion of Digital Earth.The initiatives aim to amplify the voice of ordinary citizens,improve citizens’capacity to directly influence public service delivery and hold local government accountable.The popularity of these innovations is,among other things,a local reaction to the partial failure of the millennium development goals(MDGs)to deliver accurate statistics on public services in Africa.Empowered citizens,with access to standard mobile phones,can‘sense’via text messages and report failures in the delivery of local government services.The public disclosure of these reports on the web and other mass media may pressure local authorities to take remedial action.In this paper,we outline the potential and research challenges of a‘participatory sensing’platform,which we call a‘human sensor web.’Digital Africa’s first priority could be to harness continent-wide and national data as well as local information resources,collected by citizens,in order to monitor,measure and forecast MDGs.
