基于模糊逻辑的大气云粒子相态反演和效果分析   总被引：4，自引：1，他引：3  

王德旺  刘黎平  宗蓉  黄宁立  谢潇  欧建军  郭巍  勾亚斌 《气象》2015,41(2):171-181

为了探究8mm云雷达探测到的大气云粒子相态特征,根据Shupe总结得到云雷达探测参量:反射率因子、Doppler径向速度、线性退偏振比以及温度在不同相态水凝物对应的云雷达产品特征阈值,采用不对称T型的隶属函数,成员函数包括:反射率因子、线性退偏振比、径向速度以及垂直温度廓线,反演出的粒子相态包括:雪、冰晶、混合相态、液水、毛毛雨、雨等6种。通过联合分析中国气象科学研究院灾害天气国家重点实验室的偏振云雷达探测资料和GTS1型探空仪温度数据,结果表明;通过模糊逻辑法对云雷达探测的参量反演出的大气粒子相态结果与探空实时数据一致性较好,对现阶段常规天气预报参考、人工影响天气作业指挥以及效果评估来说具有较好指导性。  相似文献   

Hillside seepage and the steady water table. I: Theory     

《Advances in water resources》1996,19(2):63-73

Steady seepage through a hillslope aquifer results in the formation of a water table. In this paper, the boundary conditions governing the steady water table location are analysed, and an analytical series method applied to the problem, using eigenfunction expansions. Eigenfunction expansions, modified for non-orthogonal basis functions, provide a conceptually simple, efficient estimation process, that reduces the steady water table problem to a sequence of curve fitting exercises. A rigorous examination of the hodograph relationships reveals the possibility of more than one water table location, for given recharge rate. An elementary analysis reveals that one of these possibilities can always be eliminated. Also, the boundary conditions governing the steady water table are determined at a non-vertical upstream boundary. Hillslopes subjected to low recharge rates can be very difficult to analyse, and appropriate techniques for this case are detailed. In a companion paper (Adv. Water Resour., 19(2) (1996) 75–81), the techniques described in this paper are put to the test, and the upstream boundary conditions are investigated, using the series methods.  相似文献   

35GHz云雷达反射率因子数据的质量控制   总被引：2，自引：2，他引：0  

王德旺  黄宁立  谢潇  浦佳伟  欧建军 《气象科学》2014,34(5):508-514

大气非云粒子(气溶胶、昆虫、悬浮物)以及雷达元器件固有噪声,是影响云雷达定量探测大气云层宏观以及微观产品的重要因素。为了剔除云雷达基数据中的散点噪声对数据质量的影响,本文利用新一代多普勒偏振8.6 mm云雷达资料,基于模糊逻辑识别地物的方法分析雷达散点噪声、气溶胶以及大气云粒子的反射率因子回波的统计特征,通过统计的特征值对反射率因子进行分类,保留正常回波数据。结果表明:该方法能较好区分云粒子回波和非云粒子回波,提高云雷达反射率因子的数据质量。  相似文献