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121.
介绍了基于Web的流动地震监测数据库查询系统的开发背景和目的,描述了数据库查询系统的设计和实现过程。该系统借助Internet/Intranet网络,以B/S(浏览器/服务器)体系结构作为基础架构,采用WAMP集成化软件开发,具有系统加密、数据查询、数据维护、数据导出和资料下载等功能。 相似文献
122.
Measuring spatial accessibility to primary care in rural areas: Improving the effectiveness of the two-step floating catchment area method 总被引:4,自引:0,他引:4
Quantifying spatial accessibility in relation to the provision of rural health services has proven difficult. This article critically appraises the two-step floating catchment area (2SFCA) method, a recent solution for measuring primary care service accessibility across rural areas of Victoria, Australia. The 2SFCA method is demonstrated to have two fundamental shortcomings – specifically the use of only one catchment size for all populations, and secondly the assumption that proximity is undifferentiated within a catchment (especially problematic when the catchment is large). Despite its advantages over simple population-to-provider ratios, the 2SFCA method needs to be used with caution. 相似文献
123.
云南宣威羊场煤矿资源潜力评价 总被引:1,自引:0,他引:1
羊场煤矿经50年开采,资源近于枯竭。通过地质调查和预测,提供可靠依据,为危机矿山新增储量,延长矿山服务年限。 相似文献
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学校图书馆是图书资料的供应与服务基地 ,其藏书量与藏书类别的多少 ,以及图书馆各专业情报资料源的数量与管理和服务水平 ,是办学条件的重要标志之一 ,因而 ,测绘图书情报资料的信息源建设、测绘科技文献的开发与利用和测绘科技情报资料为师生的服务 ,在测绘教育中有着举足轻重的地位与作用。 相似文献
126.
洞庭湖流域水生态系统服务功能经济价值研究 总被引:9,自引:2,他引:9
以洞庭湖流域水生态系统为例,在明确河湖库塘生态系统服务功能内涵的基础上,运用生态学与生态经济学方法对洞庭湖流域各类水生态系统服务功能经济价值进行了评估。结果表明,全流域河湖库塘水生态系统服务功能总价值量为1106.19亿元,约占湖南省2004年GDP(5612.26亿元)的19.7%,其中,城镇和农村生活供水、工农业生产供水、水力发电、内陆航运等直接利用价值为415.698亿元;调洪、输沙、水资源贮存等间接利用价值为690.492亿元。可以认为,流域水生态系统服务功能对湖南省工农业生产的持续发展,维系生态环境健康和人民生命财产安全起到了不可替代的支撑和保障作用。 相似文献
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Artemis Skarlatidou Muki Haklay Tao Cheng 《International journal of geographical information science》2013,27(12):1913-1930
Since the introduction of Xerox PARC Map Viewer, there is a high growth in the number of Web GIS (Geographical Information System) applications for public use in different contexts. These applications instruct, advise and provide the tools for spatial analysis to their users, and the people who use them depend or rely on these systems. Many of these users are non-experts who have no GIS expertise and a limited understanding of spatial data handling. These inherent characteristics of non-expert interaction establish risk and uncertainty, which are further increased due to the complexity of Web GIS interfaces. These issues of uncertainty, risk perception and dependence are all trust-related aspects. Online trust has been repeatedly identified as a major concept for online information systems and its value recognised as it influences the intentions to use and the acceptance of online systems and the overall user experience. However, there is a very limited understanding as to exactly how trust is constructed when people, especially non-experts, interact with Web GIS. To improve knowledge in this domain, this article explores the theoretical foundations on how trust can be investigated in this context. Trust studies (mainly from the e-commerce domain) suggest that a trust-oriented interface design may improve the trustworthiness of online systems, and such attention can be given to Web GIS interfaces. Such studies are reviewed and their applicability is considered in the Web GIS context, taking into consideration their special characteristics. A case study is used to discuss how some features may potentially influence the trustworthiness of Web GIS applications. This article concludes by suggesting future research directions for the implementation of a holistic approach, which is necessary to investigate trust in this context. 相似文献
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130.
This paper investigates the variation of the popular curve number (CN) values given in the National Engineering Hand Book–Section 4 (NEH‐4) of the Soil Conservation Service (SCS) with antecedent moisture condition (AMC) and soil type. Using the volumetric concept, involving soil, water, and air, a significant condensation of the NEH‐4 tables is achieved. This leads to a procedure for determination of CN for gauged as well as ungauged watersheds. The rainfall‐runoff events derived from daily data of four Indian watersheds exhibited a power relation between the potential maximum retention or CN and the 5‐day antecedent rainfall amount. Including this power relation, the SCS‐CN method was modified. This modification also eliminates the problem of sudden jumps from one AMC level to the other. The runoff values predicted using the modified method and the existing method utilizing the NEH‐4 AMC criteria yielded similar results. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献