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排序方式: 共有1018条查询结果,搜索用时 15 毫秒
101.
Location-Based Services (LBS),an emerging new business based on smartphone and mobile networks,are becoming more and more popular.Most of these LBSs,however,only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role.Our specific aim is to solve these issues.This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders.  相似文献   
102.
基于SOA的数字城市公共平台设计与实现   总被引:1,自引:0,他引:1  
杨丽娜  彭玲  池天河  孙旭 《测绘科学》2011,36(6):230-232,186
针对城市信息化建设中存在的建设周期长、开发成本高、运行维护困难等问题,本文从软件架构、系统功能、服务性能等方面进行研究,设计并开发基于SOA的数字城市公共平台。平台采用松散耦合的WebSer-vices、Ajax等技术,结合数据资源控制访问、平台架构分离等策略,实现对多源异构空间数据的分布式集中管理和授权共享,封装形成统一的服务接口及应用框架,辅助业务系统的快速搭建与无缝集成;并在二维GIS基础上扩展添加三维GIS服务。  相似文献   
103.
福建省地理信息公共服务平台数据应用服务模式探讨   总被引:1,自引:0,他引:1  
介绍了福建省地理信息公共服务平台数据构成和应用服务,探讨了针对不同用户类型、不同网络环境下的平台数据共享应用服务模式,实现横纵向部门间数据服务的互联互通,为政府、企业和社会公众提供地理信息基础支撑。  相似文献   
104.
从地理信息服务的内涵、发展和社会需求等几个方面对地理信息服务进行综合分析,从而提出了加强地理信息服务的几点建议.  相似文献   
105.
多重加密格网内插法坐标转换   总被引:1,自引:0,他引:1  
我国CGCS2000坐标系启用后,各地均面临着大批量、多类型、多坐标系成果数据坐标转换的需求,而国家大地坐标系、地心坐标系及独立坐标系之间的转换参数属于绝密级别,保密要求高,因此给实际应用带来了困难。顾及与参数法坐标转换成果的一致性及数据的安全要求,本文提出了多重加密格网内插坐标转换方法,研制了适用于多种数据格式的二/三维格网坐标转换软件,并将该算法应用于CORS服务,通过实例验证了该方法的可靠性与实用性。  相似文献   
106.
陈波  崔蓓  丁鑫 《测绘通报》2020,(12):75-78
自然资源部制定的信息化建设总体方案中,要求构建“互联网+自然资源政务服务”应用体系,实现“服务事项标准统一、整体联动、业务协同,自然资源政务服务和共享开放能力全面提高”。一体化政务服务系统作为政务服务应用体系的重点建设内容,也是落实自然资源管理“两统一”职责的重要支撑,如何整合各类数据资源、发挥系统作用,成为亟待研究的问题。本文在分析自然资源业务管理需求后,提出了一体化政务服务系统及数据融合的建设思路。  相似文献   
107.
The Lower Mississippi Alluvial Valley (LMAV) was home to about ten million hectare bottomland hardwood (BLH) forests in the Southern U.S. It experienced over 80 % area loss of the BLH forests in the past centuries and large-scale afforestation in recent decades. Due to the lack of a high-resolution cropland dataset, impacts of land use change (LUC) on the LMAV ecosystem services have not been fully understood. In this study, we developed a novel framework by integrating the machine learning algorithm, county-level agricultural census, and satellite-based cropland products to reconstruct the LMAV cropland distribution during 1850–2018 at a 30-m resolution. Results showed that the LMAV cropland area increased from 0.78 × 104 km2 in 1850 to 6.64 × 104 km2 in 1980 and then decreased to 6.16 × 104 km2 in 2018. Cropland expansion rate was the largest in the 1960s (749 km2 yr−1) but decreased rapidly thereafter, whereas cropland abandonment rate increased substantially in recent decades with the largest rate of 514 km2 yr−1 in the 2010s. Our dataset has three notable features: (1) the depiction of fine spatial details, (2) the integration of the county-level census, and (3) the inclusion of a machine-learning algorithm trained by satellite-based land cover product. Most importantly, our dataset well captured the continuous increasing trend in cropland area from 1930–1960, which was misrepresented by other cropland datasets reconstructed from the state-level census. Our dataset would be important to accurately evaluate the impacts of historical deforestation and recent afforestation efforts on regional ecosystem services, attribute the observed hydrological changes to anthropogenic and natural driving factors, and investigate how the socioeconomic factors control regional LUC pattern. Our framework and dataset are crucial to developing managerial and policy strategies for conserving natural resources and enhancing ecosystem services in the LMAV.  相似文献   
108.
Optimization of land use structure consists of economic and social and ecological optimization. Applying the minds of system engineering and principles of ecology, this paper presents such thoughts: the optimal forest-coverage rate calculated according to the reality of a district is set as main standard of ecological rationality in the district; through considering the value of ecosystem services of the land with GREEN equivalent (mainly cultivated land and grassland) and based on the rule, GREEN equivalent, this paper introduces the area conversion between woodland and cultivated land, also between woodland and grassland; this paper establishes a multi-dimension controlling model of optimization of land use structure. In addition, a multi-objective linear programming model for optimization of land use structure is designed. In the end, this paper tests and verifies this theory of ecological optimization, taking Qionghai city in Hainan Province as an example.  相似文献   
109.
Location-Based Services (LBS), an emerging new business based on smartphone and mobile networks, are becoming more and more popular. Most of these LBSs, however, only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role. Our specific aim is to solve these issues. This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders.  相似文献   
110.
随着浙江省天然气供应规模的逐步扩大,应用领域的不断拓展,用WebGIS对天然气管线进行管理更显其优势。气象条件的变化与天然气供需有着密切的联系,本文基于WebGIS建立了浙江省天然气调控应急保障气象服务系统。对天然气管网数据进行了整理,并结合气象数据进行了分析和统一存储及管理。系统采用B/S架构,实现了天然气管道沿线实况监测、沿线天气预报、沿线气象历史资料查询、管网负荷预测、地图管理和操作、系统管理和维护等功能。探索了气象条件对燃气负荷的影响规律,能及时查询天然气沿线的天气实况和预报,为天然气调控应急保障提供了直观的气象服务和数据保障。  相似文献   
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