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141.
如何分析一个地区在未来地震中的经济损失水平,对于在现阶段采取相应的防震减灾对策有很大的决策参考意义。过去的振害损失预测分析,一般在考虑地震危险性时是有概率水平的,可是在分析震害及经济损失时,没有充分考虑这些因素的概率特征。本文从全概率的公式为基础,建立了区域震害经济损失预测的概率分析模型,综合考虑了地震、场地、结构和当地经济发展水平的影响。进而在对这个模型作一些简化以后,提出了以结构物破坏等级为基础的震害经济损失分析预测方法。此外,本文在如何考虑场地液化等方面也作了分析探讨。  相似文献   
142.
基于大气模式CAM5对比分析了三套基于物理过程发展而来的冰晶核化参数化方案,包括BN方案、KL方案和CAM5自带的LP方案。针对三个方案的离线测试结果表明,由LP和BN方案计算得出的冰晶数浓度随硫酸盐溶液滴的数浓度增加而明显增加,而KL方案对硫酸盐溶液滴的数浓度不敏感;CAM5模拟结果显示,这三套方案得出的云辐射强迫、冰晶数浓度及其概率分布非常相似,基本上都接近观测。但是,使用KL方案得出的全球平均云长波辐射强迫从工业革命前到当代增加0.05 W·m~(-2),明显低于LP方案的0.36 W·m~(-2)和BN方案的0.33 W·m~(-2);由此可见,选择哪个冰晶核化参数化方案不会明显影响模式对冰云的模拟性能,但对评估人为产生气溶胶的间接效应可能有显著影响。  相似文献   
143.
IndirectapproachmethodforspecifiedendpointsseismicraytracinginthredimensionalinhomogeneousmediaCHAOFANXU(徐朝繁)XIANKANGZH...  相似文献   
144.
大黄鱼溶藻弧菌LPS的间接ELISA检测   总被引:9,自引:0,他引:9  
用酚 水法从20dm3溶藻弧菌培养液中分离得到脂多糖(LPS)97.6mg,以0.5mg cm3的LPS溶液通过耳缘静脉注射免疫实验兔,经过3次加强注射后从颈动脉放血制备抗血清.该抗血清的效价为1∶2560,对副溶血弧菌等10株细菌的交叉反应效价都较低.用免疫吸附过滤法去除血清中的非特异性成分.用吸附后的抗血清进行溶藻弧菌间接ELISA检测,其检测限为97×104个 cm3.以ELISA进行大黄鱼体内溶藻弧菌检测.结果表明:用LPS抗血清可以较为灵敏地检测大黄鱼体内的溶藻弧菌,该方法不仅可以用于诊断大黄鱼的溶藻弧菌病,也可以检测无病症带菌大黄鱼.  相似文献   
145.
The deployment of the U.S. Atmospheric Radiation Measurement mobile facility in Shouxian from May to December2008 amassed the most comprehensive set of measurements of atmospheric, surface, aerosol, and cloud variables in China.This deployment provided a unique opportunity to investigate the aerosol–cloud interactions, which are most challenging and, to date, have not been examined to any great degree in China. The relationship between cloud droplet effective radius(CER) and aerosol index(AI) is very weak in summer because the cloud droplet growth is least affected by the competition for water vapor. Mean cloud liquid water path(LWP) and cloud optical depth(COD) significantly increase with increasing AI in fall. The sensitivities of CER and LWP to aerosol loading increases are not significantly different under different air mass conditions. There is a significant correlation between the changes in hourly mean AI and the changes in hourly mean CER,LWP, and COD. The aerosol first indirect effect(FIE) is estimated in terms of relative changes in both CER(FIECER) and COD(FIECOD) with changes in AI for different seasons and air masses. FIECODand FIECERare similar in magnitude and close to the typical FIE value of ~ 0.23, and do not change much between summer and fall or between the two different air mass conditions. Similar analyses were done using spaceborne Moderate Resolution Imaging Spectroradiometer data. The satellite-derived FIE is contrary to the FIE estimated from surface retrievals and may have large uncertainties due to some inherent limitations.  相似文献   
146.
叶面积指数间接测量方法   总被引:2,自引:0,他引:2  
叶面积指数是对地遥感的关键参数。间接测量法快速高效,已广泛应用于叶面积指数的地面测量和遥感验证中,服务于众多行业和领域,表现为论文被引数远远大于发文数。从理论基础、代表算法、测量仪器、影响因素几个方面全面总结了叶面积指数间接测量方法的发展和现状,指出聚集/尺度效应、叶倾角分布、木质组分、地形效应是影响测量精度的关键因素,针对这些影响因素对未来发展方向进行了展望。  相似文献   
147.
A risk analysis is developed for a test site located in the area north of Lisbon using a scenario of a temporary interruption of the motorway A9 due to a landslide of rotational or translational type. Landslide susceptibility is assessed at the regional scale independently for rotational and translational slides, comparing the landslide distribution with a set of assumed independent landslide predisposing factors. Susceptibility models are validated and classified through the computation of prediction rate curves based on the temporal partition of the landslide data sets. Landslide hazard maps are based on a scenario of future landslide occurrence for the next 27 years. These maps allow the definition of two critical areas on the motorway A9 with regards to landslide susceptibility. Direct costs associated with both critical spots are assessed taking into account the probable affected area of the motorway, and the reconstruction costs. Indirect costs derived from the traffic interruption are evaluated considering the alternatives paths to the motorway, and include costs resulting from: (1) additional fuel consumption; (2) decrease in tollgate income; and (3) loss of productive time. Results show that indirect costs may be 24 to 43 times higher than direct costs, assuming a temporary interruption of the motorway for 6 months.  相似文献   
148.
碘量法快速测定电解金属锰中硒   总被引:1,自引:0,他引:1  
王香桂 《岩矿测试》2006,25(1):93-94
采用在HCl介质中定量加入Na2S2O3溶液,用淀粉作指示剂,过量的Na2S2O3以碘标准溶液进行滴定,间接测定电解金属锰中的硒。方法的加标回收率为92.5%-107.5%,对w(Se)=0.078%的样品进行10次测定的RSD为3.02%,用于实际样品测定,结果与国标法相符。  相似文献   
149.
地壳应力状况主要是由重力和构造作用力引起的, 文章提出"构造附加静水压力"概念,认为地壳任一点静水压力是由重力所附加的静水压力和构造作用力所附加的静水压力叠合而成.并指出,构造叠加致使同一地壳深度的水平面上静水压力值不相等,这种压力梯度是流体及油气长距离水平运移的主要原因;通过建立岩石矿床形成深度的构造校正测算方法,得出胶东"玲珑-焦家式"金矿成矿深度仅3 km左右,这一结果得到区内找矿工程的初步验证,进而测得大别超高压变质带含柯石英榴辉岩形成深度≥32km,它们可能是壳内构造物理化学过程的产物;逐步形成构造通过影响物理化学环境的方式影响成岩成矿地球化学过程,即构造物理化学成矿的新认识,探讨应用构造物理化学场结构分析与界面成矿的观点进行预测未知区隐伏矿床.  相似文献   
150.
ABSTRACT

The optimization and extension of existing gauging networks are a challenging task, which can be done under consideration of many different aspects. One possibility is to maximize the obtained information on regional hydrological characteristics by new gauges compared to existing ones. For this, information theory approaches are most suitable. Here, the principle of maximum entropy is applied to calculate the probability of non-similarity of catchments to determine locations of new gauges according to the catchment characteristics that are most relevant for the hydrological conditions. The realization in an interactive application, provided online, makes use easy for practitioners and scientists. Goodness-of-fit measures are applied to investigate the explanatory power of the model and the contribution of each characteristic to the model, which gives information on the most influential properties of the catchment. The relevance of the proposed approach is proven by comparing hydrological signatures between similar and non-similar catchment.  相似文献   
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