中国人工增雨研究进展

随着全球气候变暖的加剧,水资源短缺问题表现得越来越突出,如何有效地开发利用空中水资源已成为人们关注的热点问题之一。本文回顾了人工增雨的发展历史,概述了当今国内外人工增雨的发展状况,归纳了各地区云状、积云特征、液态含水量、冰晶浓度等云物理特征,并在此基础上对我国各地区尤其是西北地区的增雨潜力进行了分析,最后归纳总结了人工增雨的常用手段、经验和检验人工增雨效果的方法。     

Characteristics of Aerosol Ionic Compositions in Summer 2003 at Lin''''an of Yangtze Delta Region

With the size-resolved aerosol mass and ion composition data obtained at Lin'an regional atmospheric pollution monitoring station in July 2003, the size distributions of aerosol mass and ionic components, and the correlations between major ion pairs were analyzed. The primary results indicate that in the period of in-situ measurement, the aerosols are mainly composed of fine particles. The mass of aerosols with size less than 2.1μm accounts for 66% of the total mass of all size ranges, in which about 50% of the mass is contributed by the particles with size less than 0.65μm. Similar to the size distributions of aerosol mass, the water-soluble ions are mainly concentrated in the size range of <0.65μm, accounting for about 77% of the sum of analyzed ions, and the ions within the range of <2.1μm reach 88%. The sulfate, ammonium, and potassium are the dominant ionic components in fine particles (particle size less than 2.1μm). Ion correlation analysis suggests that the sulfates in fine particles are mostly in the compounds of (NH4)2SO4, Na2SO4, and K2SO4, but for submicron particles the sulfates are mainly in the form of (NH4)2SO4.     

可数背景状态下QBD过程的平稳分布尾渐近态

考虑在可数背景状态下，时间离散的拟生灭过程（QBD过程）平稳分布的尾概率的渐近态。通过对QBD过程某些条件的限定，应用马尔可夫更新定理，得出在一定合理的条件下，当水平趋于无穷时的尾概率的几何衰变。通过初等方法，将该结论应用于时间离散的加入最短队模型。     

中国大陆及邻区、川滇成组强震活动特征初步研究

将中国大陆及其邻区1902年以来MS≥7地震的成组活动划分出7组,其首发大震分别为1902年阿图什8.2级,1911年阿拉木图8.2级,1920年海原8.5级,1931年富蕴8.0级,1946年缅甸7.8级,1966年邢台7.2级,1988年缅甸7.2级。川滇MS≥6.7地震成组活动划分出5组,其首发强震为1913年峨山7.0级,1933年茂县7.5级,1948年理塘7.3级,1966年东川6.5级、6.2级,1988年澜沧7.4级。其中,川滇MS≥7的首发大震滞后中国大陆首发大震几个月至4年不等。按成组大震的界定,目前中国大陆处于1998~2007年(估计)的大震少发时段。川滇未来1~2年的大震形势为川滇西部存在发生大震的可能性。中国大陆新一轮强震成组活动中的大地震将可能在2007~2009年前后发生,主体危险区可能为天山地震带中段及川滇东部。2007~2008年可能出现5~6级地震的增强过程。巧家—东川一带可能最先发生6级地震。     

康定温泉逸出气短期预测研究

康定温泉逸出气气体百分含量的观测始于1986年,期间先后经历了多次甘孜州及邻区5.0级以上地震。地震前康定温泉逸出气观测资料均有不同程度的短临异常。本文在系统整理和深入剖析两泉点自有观测以来的在甘孜州及邻区发生的5.0级以上地震震例资料的基础上,借助多次“攻关”成果,排除观测资料的各种干扰因素及仪器标定变更情况,总结各观测资料短临异常特征、中短期异常特征及中短期异常特征随时间变化规律,提出康定温泉逸出气短临异常指标。     

Study on financial loss and its adjustment in earthquake insurance

Introduction Earthquake often brings large catastrophe to the mankind, especially in recent years when a large number of destructive earthquakes occur in the whole globe, which have caused tremendous casualties and losses to the people. Obviously, it is not very reasonable to make up financial losses and carry out post-seismic reconstruction by the government only for such kind of huge earth- quake losses. Therefore, as an effective measure to raise fund and make up financial losses, earth- qu…     

Interrelation among several important links in seismic risk analysis

Introduction In the probability analysis method of seismic risk considering time-space inhomogeneity of seismic activity and adopted commonly in China (State Seismological Bureau, 1996) (called in-homogeneous distribution model for short), the division of seismic statistical regions, delimitation of potential seismic sources and estimation of seismicity parameters are the main links that affect significantly the estimation of ground motion parameters of a site. HUANG and WU (2005) studied …     

Application of ensemble kalman filter to geophysical parameters retrieval in remote sensing:A case study of kernel-driven BRDF model inversion

Remote sensing can provide multi-spatial resolution, multi-temporal resolution multi-spectral band and multi-angular data for the observation of land surface. At present, one of research focuses is how to make the best of these data to retrieve geophysical parameters in conjunction with their a priori knowledge and simul-taneously consider the influence of data uncertainties on inversion results[1-5]. The essence of remote sensing lies in inversion. It is difficult to precisely retrieve parame…     

Hydraulic analysis of cell-network treatment wetlands

When individual cells of a multiple-cell treatment wetland are hydraulically connected, the wetland has a cell-network structure. The hydraulic performance of treatment wetlands is often characterized using tracer residence time distributions (RTDs) measured between the wetland inlet and outlet, such that the wetland is considered as a single hydraulic unit, regardless of the extent of networking between individual internal cells. This work extends the single hydraulic unit approach to enable the specification of moments and RTD parameters for individual cells, or clusters of cells, within the cell-network based on inert tracer tests with injection only at the network inlet. Hydraulic performance is quantified in terms of hydraulic efficiency and travel time dimensionless variance using both the method of moments and RTD modeling. Cell-network analysis was applied to a case study from the Orlando Easterly Wetland (OEW), demonstrating the improvement in hydraulic performance of individual wetland cells following wetland restoration activities. Furthermore, cell-network analysis indicated that the location of water quality sampling station locations within the cell network can significantly affect the accuracy of pollutant removal effectiveness estimation when the individual sample station RTD does not represent the hydraulic unit RTD. At the OEW, it was determined that historical nutrient removal effectiveness estimation may be underestimated for one area and overestimated for another, and recommendations were provided for sample station locations to minimize future performance estimation errors.