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91.
92.
Ana E. Seguí José L. Lerma Santiago Navarro Cristina Portalés 《The Photogrammetric Record》2009,24(127):280-294
Aerial images are valuable products when dealing with both geospatial and geotemporal analysis. Nowadays, they are widely used for many different purposes and by an extensive public, including private companies, official administrations and individual users. Although in the past few years there has been an increasing interest in showing all kinds of geographical information on the World Wide Web, access to aerial imagery and its dissemination are still difficult and lack flexibility. This paper introduces an aerial imagery management system based on client–server principles, operated so as to allow users quick and efficient queries, processing and management of huge sets of photogrammetric imagery stored on raster servers. It is a novel product that is ready to provide image-based cartographic data available in public and private digital warehouses, facilitating all the required visualisations and queries, as well as geometric and radiometric processing on the fly. This paper shows the design, system architecture and various functionalities of the system in a real-life scenario. 相似文献
93.
94.
西安地热田医疗热矿水的产出状况分析 总被引:1,自引:0,他引:1
本文介绍了西安地热田概况及开采现状, 重点讨论了西安地热田医疗热矿水的产出状况 相似文献
95.
公共服务设施可达性及其对新建住房价格的影响——以北京中心城为例 总被引:8,自引:0,他引:8
本文基于北京市公共服务设施的地理空间信息数据, 采用最短距离指标定量分析了商品 住房对教育、医疗、体育、文化、商业、绿地公园等6 大类公共服务设施的空间可达性( 以下简称 “可达性”) , 并通过Hedonic 特征价格模型定量分析可达性对商品住房价格的影响。研究结果表 明: 1) 按照“最短距离”可达性比较, 商品住房对绿地公园、医院和健身场所可达性最好, 而对大型 商场、文化设施、体育场馆的可达性较差; 2) 按照商品住房的区位和价格比较, 城市四环以内和高 价商品住房组别对公共服务设施的可达性明显优于其它组别; 3) 特征价格模型的定量分析表明, 重点高中、球类场馆、文化设施和绿地公园这4 种公共服务设施的可达性越好, 则商品住房价格 越高, 即目前北京市公共服务设施的规划布局在一定程度上被资本化入商品住房价格。 相似文献
96.
97.
Antoine S. Bailly 《The Professional geographer》1995,47(1):70-74
Four directions in producer services research in Europe are identified: the economic role of producer services for urban and regional development; the location of advanced producer services; the role of regional structures and innovative “milieu”; and local development and labor markets. Issues for future research include the role of producer services in the urban structuring and/or restructuring of world cities; the relation between producer services and interregional disparities; the integration of producer services into networks; and the impacts of the liberalization of producer services. 相似文献
98.
Producer Services Research in the United Kingdom 总被引:1,自引:0,他引:1
Peter W. Daniels 《The Professional geographer》1995,47(1):82-87
This paper reviews recent research in the United Kingdom on producer services and suggests directions for further research. A recurrent theme in UK-based geographic research into producer services is the role of service activities, establishments, and trade in uneven development of the UK space economy, a role manifested in uneven provision and quality of services in peripheral regions. During the 1980s, overall growth in demand for producer services and the rapid rise in metropolitan London real estate costs reduced London's dominance, but these trends moderated by the end of the decade. In the absence of adequate government statistics, regular and standardized surveys are needed to compile a time series of service change in the United Kingdom. Directions for continued empirical research include the role of producer services in innovation and technology transfer, the implications of information technology for the location of employment in the sector, and the impacts of productivity increases on employment and wages. 相似文献
99.
Jeff R. Crump 《The Professional geographer》1993,45(3):286-296
The purpose of this research is to analyze the composition and distribution of Department of Defense (DOD) services procurement. The results indicate producer services comprise 53% of DOD services outlays. Defense expenditures for services are particularly important in the Washington, D.C., region and in states that either produce weapons or house defense-related R&D facilities. Defense expenditures are providing impetus to service sector growth in Virginia and, simultaneously, are providing the initial stimulus for development of producer services in states such as New Mexico. 相似文献
100.
A Spatial Variant of the Basic Reproduction Number for the New Orleans Yellow Fever Epidemic of 1878
Andrew Curtis Jacqueline W. Mills Jason K. Blackburn 《The Professional geographer》2007,59(4):492-502
A spatial variant of the basic reproduction number (R0), here defined as the number of subsequent deaths attributed to an initial mortality, can be used to identify geographic variation within an epidemic. A spatial R0 was calculated at the neighborhood level, here defined by a 50‐m buffer surrounding an index case, for mortality data from the 1878 yellow fever epidemic of New Orleans. The highest number of secondary mortalities linked to a neighborhood index case was twelve, with a further eighty‐seven extrapolated morbidity cases. Results also highlight the importance of multideath residences and cultural contacts in neighborhood‐level disease spread. 相似文献