PROBLEMS IN WEIGHTING OF HYETOGRAPHS1

ABSTRACT: It was found that the conventional weighting factor application to hyetograph ordinates results in artificially attenuated storm patterns. A modified weighting procedure is suggested which allows adjustments in the storm timing, peak intensity, and volume but conserves the storm pattern observed at the raingage nearest to the watershed point of interest. The systematic underestimation of peak flood flows, which result from conventional hyetograph weighting, can be avoided by conserving the hyetograph shape from the raingage nearest to any subarea of a modeled watershed and merely applying weighting factors to the rainfall volumes and temporal center of gravity of several hyetographs.     

室内环境中化学污染物质测定法研究

室内环境中化学污染物质的测定是研究和解决室内环境问题的基础。本文以甲醛和挥发性有机化合物两种室内环境中的主要化学污染物质为例,介绍了目前世界各国采用的各种测定法及其动向,并探讨了测定时期、测定时间、采样点布置等有关问题,提出了一些看法供参考。     

地应力壶与临震预测

设计和安装了地应力壶，在１９７７～１９７８年进行了观测。用日变曲线异常进行临震预测。在地震三要素预测中，发震时间预测较准确；在地点上震中方位角预测较准，震中距难以预测；震级预测误差较大。     

基于灰局势决策的火灾形势评价方法

简要介绍灰局势决策的基本原理。以灰局势决策的多目标方案选优思想为基础,运用灰局势决策中统一效果测度的计算方法,对火灾统计数字进行灰处理。通过对反映火灾形势的4项基本指数进行测度变换、测度运算等处理,将原先相对独立的统计数字统一到一个可以涵盖原有数据有效信息的单一测度之下,从而得到一个可以评价各参评时段之间相对火灾形势的综合指标,以此为依据实现了对火灾形势的综合评价。结合实例,具体说明基于灰局势决策的火灾形势评价方法的操作过程。     

关于死亡赔偿计算方法的探讨

目前我国关于死亡事故的赔偿标准一是太低,二是标准不一致.由此产生的后果不仅使私了现象增多,增加了社会隐患而且怂恿了极个别肇事者采取故意至受伤者死亡的手段来减少自身的赔偿损失,严重危害了基本的人性道德标准.本文在认真分析的基础上,提出了"生命损失赔偿理论"的新思路,即针对死亡者因生命丧失带来的三大损失提出了科学的赔偿理论依据和计算方法,使死亡赔偿力求做到:客观、公正、科学、合理.     

灾害易损性研究的回顾与展望

近十余年来,易损性研究成为灾害学术研究和国际社会发展减灾策略的一个主题.本文概述了易损性研究的历史发展过程,评述了易损性的三类概念,总结了易损性的四个性质,阐述了易损性识别和测量的一些基本理念和方法,指出了易损性分析在灾害研究和减灾防灾中的积极意义.     

RAINGAGE NETWORK DESIGN USING NEXRAD PRECIPITATION ESTIMATES1

ABSTRACT: A general framework is proposed for using precipitation estimates from NEXRAD weather radars in raingage network design. NEXRAD precipitation products are used to represent space time rainfall fields, which can be sampled by hypothetical raingage networks. A stochastic model is used to simulate gage observations based on the areal average precipitation for radar grid cells. The stochastic model accounts for subgrid variability of precipitation within the cell and gage measurement errors. The approach is ideally suited to raingage network design in regions with strong climatic variations in rainfall where conventional methods are sometimes lacking. A case study example involving the estimation of areal average precipitation for catchments in the Catskill Mountains illustrates the approach. The case study shows how the simulation approach can be used to quantify the effects of gage density, basin size, spatial variation of precipitation, and gage measurement error, on network estimates of areal average precipitation. Although the quality of NEXRAD precipitation products imposes limitations on their use in network design, weather radars can provide valuable information for empirical assessment of rain‐gage network estimation errors. Still, the biggest challenge in quantifying estimation errors is understanding subgrid spatial variability. The results from the case study show that the spatial correlation of precipitation at subgrid scales (4 km and less) is difficult to quantify, especially for short sampling durations. Network estimation errors for hourly precipitation are extremely sensitive to the uncertainty in subgrid spatial variability, although for storm total accumulation, they are much less sensitive.     

利用超声波CT的容器内温度测量

本研究的目的是建立一种应用超声波CT原理测量容器内温度分布的非破坏性检测方法.为了详细描述超声波穿过铝管的传播过程(铝管内装满水),基于FDM(有限差分方法)编制的计算机源码用于计算机模拟,计算模拟结果与测定的超声传播时间相当吻合.同时,建立了一套温度测量的实验装置,以测定管道内的平均温度和温度分布,在温度分布测量中,CT技术被用于测量管道内的对称温度分布.结果显示整个测定系统的测量误差不超过±2度.     

典型装备温度响应测量及平衡时间研究

目的 研究武器装备在温度环境试验过程中温度的测量方法和温度平衡稳定的时间。方法 利用直接测量方法对3种典型装备进行温度响应时间测量和分析,找出不同类型装备的传热规律,明确其温度环境试验的作用机理,确定装备的温度平衡时间。结果 通过多项试验测试的数据分析了武器装备温度试验应力的选取,在低温和高温工作试验时,整体温度平衡所需时间应适当延长8～10h,高温贮存时间偏短,应适当延长4～6h。结论 在武器装备温度环境试验中,应根据自身性能特点获得装备的真实温度相应特性,在条件允许的情况下,尽可能地敞开武器装备的密闭空间,加快热交换,以缩短达到温度平衡的时间。对于关键及敏感部件,应实时进行温度响应测量,保证试验量级选取的科学合理,为装备环境分析及试验方案的制定提供参考依据。