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141.
为北京铁路局各级防洪指挥部门 ,在汛期能够实时掌握所辖铁路范围内的降雨量情况 ,实现主动防洪 ,并做好铁路抗洪抢险准备工作 ,确保汛期铁路行车安全 ,笔者研究和开发了北京铁路局“降雨量远程实时监测系统”。概要介绍了系统软件的运行环境、数据库设计、系统功能以及系统达到的技术性能指标 ;重点分析了系统软件中数据的传输 ,以地理信息系统为平台的实时动态显示以及实时数据在Internet网上的发布技术 ;同时给出了系统在北京铁路局的应用案例 相似文献
142.
基于GIS的建筑物地震次生火灾危险性模拟 总被引:1,自引:1,他引:0
地震次生火灾对人类的危害极大 ,192 3年日本关东大地震中 ,大火烧毁了 4 4 .7万栋房屋 ,烧死5 .6万余人。笔者计算了建筑物发生地震次生火灾概率的大小 ,并在此基础上对建筑物发生地震次生火灾的危险性进行了模拟。通过对基于GIS的建筑物地震次生火灾危险性模拟 ,为预防地震次生火灾的发生提供有力的依据 ,同时为地震次生火灾发生后进行应急救灾提供了有力的支持。 相似文献
143.
144.
体育教学过程中,教学效果的好坏取决于师生双方对过程的调控程度,而对技能教学的调控,则依据教师的教学反馈和学生的自我反馈来实现。在体育教学过程中,教学反馈与自我反馈的有机结合,是提高教学质量的关键。 相似文献
145.
Specifying information needs: improving the working methodology 总被引:1,自引:1,他引:0
Jos G. Timmerman Joop Boer Matthijs Hisschemöller Wim Mulder 《Regional Environmental Change》2001,2(2):77-84
Specification of information needs is an important step in the design of monitoring networks. Within the framework of Monitoring
Strategy 2000+, a programme of the Dutch Directorate General of Public Works and Water Management (Rijkswaterstaat) which
seeks to provide innovation in the monitoring sector, a method has been developed to link water management policy to monitoring
through specification of information needs. Over the past 2 years, this method has been applied in several projects within
the Rijkswaterstaat organisation. Use of this method has led to improvements in the monitoring practice and was judged very
positively by the people involved. Nevertheless, the main obstacle to employing the method was the actual translation of policy
matters into information products. A special study is carried out, focusing on this aspect within the method, to provide the
participants of a project with a mental framework that enables them to clearly specify their information needs. The major
requirements for this mental framework are that all participants have a clear view of the process (system), and that they
are able to relate their contribution to this process and to the contributions of others (transparency). The first step of
the process is to focus the attention of stakeholders on the information they will actually need for decision-making. The
next step is to confront the different expressed opinions through the method of the 'devil's advocate', which implies criticising
the results of the first step by finding as many as possible arguments against these opinions. This should force the stakeholders
to better specify their arguments. The method, its improvements and the results of one pilot project will be discussed in
this paper.
Electronic Publication 相似文献
146.
147.
During the last few years in the Netherlands an integrated environmental policy has been developed. Solving environmental problems by means of effective and efficient solutions requires that the entire environmental cycle be considered in order to take all relevant compartments and aspects into account. Four different phases can be identified during the treatment of an environmental problem by management: recognition, formulation, solution, and control.Some qualitative and quantitative aspects of the information demand of environmental policy are explored. Special attention is given to the consequences of the integral approach in environmental policy in terms of information requirements. The process of information supply starts with an analysis of the demand. Subsequently data from the environmental cycle have to be selected, aggregated, and presented adequately. Further, integrated environmental policy puts increased demands on the associative power of environmental information systems. 相似文献
148.
本文通过本单位档案目标管理考核, 提出进一步完善环保档案管理工作, 是环保事业的需要。从以下四方面谈一谈认识。 相似文献
149.
Marcelo Reginato Thomas C. Piechota 《Journal of the American Water Resources Association》2004,40(6):1537-1551
ABSTRACT: A Geographic Information System (GIS) based non‐point source runoff model is developed for the Las Vegas Valley, Nevada, to estimate the nutrient loads during the years 2000 and 2001. The estimated nonpoint source loads are compared with current wastewater treatment facilities loads to determine the non‐point source contribution of total phosphorus (TP), total nitrogen (TN), and total suspended solids (TSS) on a monthly and annual time scale. An innovative calibration procedure is used to estimate the pollutant concentrations for different land uses based on available water quality data at the outlet. Results indicate that the pollutant concentrations are higher for the Las Vegas Valley than previous published values for semi‐arid and arid regions. The total TP and TN loads from nonpoint sources are approximately 15 percent and 4 percent, respectively, of the total load to the receiving water body, Lake Mead. The TP loads during wet periods approach the permitted loads from the wastewater treatment plants that discharge into Las Vegas Wash. In addition, the GIS model is used to track pollutant loads in the stream channels for one of the subwatersheds. This is useful for planning the location of Best Management Practices to control nonpoint pollutant loads. 相似文献
150.
ABSTRACT: Investigating natural, potential, and human-induced impacts on hydrologic systems commonly requires complex modeling with overlapping data requirements, plus massive amounts of one- to four-dimensional data at multiple scales and formats. Given the complexity of most hydrologic studies, the requisite software infrastructure must incorporate many components including simulation modeling and spatial analysis with a flexible, intuitive display. Integrating geographic information systems (GIS) and scientific visualization systems (SVS) provides such an infrastructure. This paper describes an integrated system consisting of an orographic precipitation model, a GIS, and an SVS. The results of this study provide a basis for improving the understanding of hydro-climatic processes in mountainous regions. An additional benefit of the integrated system, the value of which is often underestimated, is the improved ability to communicate model results, leading to a broader understanding of the model assumptions, sensitivities, and conclusions at a management level. 相似文献