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31.
ABSTRACT: Rainstorms which exceed the design capacity of conveyance systems and cause extensive damage to structures and property, occur frequently in Alberta. After such a severe storm, an early and quick assessment of the storm's location and magnitude and the corresponding frequency for various duration (storm intensity-duration curve) is often required to estimate the damage. The storm intensity-duration curve is produced with information obtained from a sparse network of recording raingages, thus, creating a high degree of uncertainty in the result. Short-duration precipitation is usually quite variable in Alberta; hencea very dense network of recording precipitation stations would be required to provide precise measurements of the storm intensity-duration curve at all locations. Such a dense network does not exist in Alberta; it would be very expensive to install, maintain, and thus difficult to justify financially. One solution for obtaining a large amount of closely spaced in-intensity-duration values is to use weather radar. Using weather radar data, intensity-duration curves could be produced routinely for any set of prespecified locations. The radar data thus have the potential for facilitating the identification of the return period of rainfall events quickly, cheaply, and precisely when the long-term intensity-duration curves are available. As a pilot project to demonstrate the feasibility of the method and the potential of the radar data, computer software was developed to derive from archived radar data, intensity-duration values for up to a 2,500 2 area for a given storm.  相似文献   
32.
地质灾害专题地图编制研究   总被引:1,自引:0,他引:1  
吕卫  宫辉力 《灾害学》1993,8(3):75-78
地质灾害专题制图是地质灾害系统研究成果的高层次综合。本文论述了地质灾害制图的目的、原则、特点、表示内容与方法,为规划决策提供地质灾害背景图件。  相似文献   
33.
利用三维积云数值模式模拟了呼和浩特地区强对流天气的发展过程,并结合实时雷达回波资料进行了对比分析,指出模式输出的部分物理量与理论值、雷达回波或地面天气及降雹(水)实况符合得较好。从对模式输出的几个物理量的统计分析,得出利用三维积云数值模式预测强冰雹过程的概念模型。结果表明,三维积云数值模式能用于模拟对流云特别是强对流云的发展过程,可在人工影响天气业务工作中应用并不断发展。  相似文献   
34.
综述了车辆事故紧急呼救技术的原理,从车辆事故检测识别技术、移动车辆定位技术、无线通信技术和地理信息系统几方面概述车辆事故紧急呼救技术的研究内容。进一步介绍车辆事故紧急呼救技术的国内外研究和应用现状,并从车辆事故识别技术、地图匹配及组合导航、集群通信及通信网络几方面总结并指出车辆事故紧急呼救技术的关键技术和难点。展望了车辆事故紧急呼救技术的发展趋势,并就我国发展车辆事故呼救技术的可行性和发展方向进行探讨。  相似文献   
35.
空中交通管制雷达管制训练分类考核方法研究   总被引:1,自引:0,他引:1  
分析当前我国管制员雷达培训考核环节中存在的问题,提出一种新的雷达管制培训的考核方法——检查单式考核,根据管制过程所涉及的各个环节以及航空器在空中的运行状态,对雷达管制培训实施分类考核。并结合一个进近雷达管制考核表的实例,分析其检查单式考核表的设计思想,详细说明其考核表记录和考核结果量化的步骤和方法。  相似文献   
36.
ABSTRACT: An extensive research program in hydrometeorology was recently initiated in the Chicago region. Major objectives are to 1) develop a real-time, prediction-monitoring system for storm rainfall using a combination of weather radar and telemetered raingage data, 2) determine precipitation measurement requirements for hydrologic design, operation, and modeling purposes, 3) define the time-space characteristics of heavy rainstorms in the Chicago urban area, and 4) establish methods for applying the Chicago findings in other cities. Basic components of the field measurement program are a network of over 300 recording raingages in 4000 mi2 in and around Chicago, plus two sophisticated weather radar systems for obtaining real-time information on storm parameters pertinent to optimizing operation of urban water resources systems. The raingage networks are to be used to compile information relevant to both design and operational aspects of urban hydrology. Radars are to be used primarily in developing the real-time operational techniques. Testing and evaluation of the real-time operational system will be done in cooperation with the Metropolitan Sanitary District of Chicago, operator of one of the most complex urban water control systems among major metropolitan areas.  相似文献   
37.
The EU Flood Directive 2007/60 requires the assessment and delineation of flood risk maps. The latter should provide the required knowledge for the development of flood risk management plans (FRMPs), that should deal with all features of risk management: e.g. preparation, protection and prevention, comprising also the phase of the flood forecasting and warning systems, in addition to the emergency management. The risk maps, delineated through the expert-drive qualitative (EDQ) approach currently adopted in several European countries, such as Italy, fail to represent the information base that needed by stakeholders for selecting the suitable objectives and designing the appropriate mitigation actions for flood risk management. In the EDQ approach, the flood hazard and the potential damage degree maps are combined by means of a matrix to obtain a qualitative flood risk map. However, the performance of the risk matrix is not usually rigorous validated and, therefore, presents limits, such as subjective and not careful explained interpretation of rating and poor resolution, (due to range compression), that can produce errors in comparative ranking of risk areas. In this context, this paper proposes the FloodRisk approach that aims to improve the efficacy of flood risk map overcoming the limits of EDQ approach in supplying the knowledge base that allow to analyze costs and benefits of potential mitigation measures. However, the proposed approach is also able to involve the citizens in the flood management process, enhancing their awareness. An application of FloodRisk procedure is showed on a pilot case in “Serio” Valley, (North Italy), and its strengths and limits, in terms of additional efforts required in its application compared with EDQ procedure, have been discussed focusing on the efficacy of the outcomes provided for the fulfillment of FRMPs. The results have demonstrated the ability of FloodRisk, respect to EDQ approach, to distinguish successfully different levels of vulnerability of exposure elements, thanks to the use of asset value and depth-damage curves, that allows a suitably evaluation of the effectiveness of risk mitigation strategies. In this light, a successfully application of a cost-benefit analysis of FloodRisk approach on a portfolio of alternative mitigation actions, (i.e. structural and non-structural measurements), has been demonstrated on the proposed study case. However, FloodRisk requires additional information, e.g. water depths assessment and assets values, and it needs a proper analysis and communication of the uncertainty in its results. Although they still exist limitations that impede, at present, the FloodRisk application without an adequate understanding and a critical consideration of the hazard, exposure and vulnerability characteristics of the study area, considerations are supplied on how the utilization of this approach can be maximized in the light of the next flood risk maps revision due by December 2019.  相似文献   
38.
The main aim of this article is to demonstrate a method of complex landscape analysis in order to estimate the landscape suitability for the construction of surface-flow wetlands (SFW) for wastewater treatment. This is a multilevel suitability analysis from a more general regional (landscape) assessment based on a map of landscape types (1:100,000) toward a detailed analysis based on aerial orthophotos and detailed soil maps (1:10,000). The assessment scheme consists of landscape classification according to the physical-chemical properties of landscape factors (soil conditions, landforms, hydrogeology, expert decisions concerning landscape values, and suitability analysis). The partial suitability values of SFWs are derived by summarizing expert values for landscape factors (each ranging from -1 to +1). By multiplying the summarized partial suitability values with nature protection values (ranging from 0 to 1), we obtain the final suitability value for each landscape type. Any kind of nature protection area has been considered nonsuitable and excluded at regional-level analysis. The results of the regional analysis demonstrate that suitability is distributed relatively equally over the study area. The high suitability potential (classified as "very suitable") is relatively evenly distributed in lowland regions throughout the country. The share of "very suitable" and "suitable" areas in different counties varies from 5 to 23% and 7 to 49%, respectively. The detailed analysis based on aerial orthophotos showed that areas suitable for SFWs can also be found within the areas determined to be unsuitable based on the less detailed map of landscape types, whereas differences are much greater between settlements chosen for the detailed suitability analysis.  相似文献   
39.
飞机的雷击附着点是飞机防雷设计研究的基础,是飞机设计中的重要过程。本文以伊尔-76飞机模型为例,依据SAE-ARP5416和国内相关标准规定的雷击附着点试验方法,采用基于传输线矩阵法的数值仿真技术对飞机的雷击附着特性展开研究,分析了机载雷达天线对飞机雷击附着点的影响,为机载雷达天线的雷电防护设计提供了理论基础。  相似文献   
40.
坡度图在滑坡研究中的应用   总被引:2,自引:0,他引:2  
王念秦 《灾害学》1991,6(3):66-70
本文阐述了坡度图的概念和作用;详细介绍了坡度尺、坡度图的作法、以及坡度图在兰州地区的应用结果;简要分析了斜坡坡度与滑坡的关系。  相似文献   
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