TBM机施工隧道瞬变电磁超前探测研究

在隧道掘进机(TBM)施工隧道内,传统瞬变电磁的装置形式受到了TBM机械的限制,TBM自身的金属构件对二次场衰减电压的采集产生了强烈的电磁干扰.为了克服瞬变电磁法在TBM施工隧道内遇到的困难,在前人工作的基础上,尝试提出了一种基于电性源激发、电场分量采集的施工隧道瞬变电磁超前探测装置形式.针对钻爆法与TBM施工隧道各自不同的工况,利用三维时域有限差分法对单个电性源激励下隧道前方瞬变电磁场的分布规律与响应特征进行了正演模拟.通过对瞬变电磁场的分布规律以及响应特征进行分析,认为所述的电性源发射装置不仅可以在钻爆法施工隧道内使用,并且具有在TBM施工隧道内进行隧道超前预报的能力.     

基于主体功能区约束的大气污染物总量控制目标分配研究

考虑经济发展水平、污染物排放现状、污染物治理水平、空气质量,特别是国家主体功能区环境目标约束等因素,构建大气污染物排放总量分配的指标体系,用改进的等比例分配方法对2015年国家SO2,NOx总量控制目标进行区域分配。分配结果表明:SO2和NOx削减量大的省份主要集中在华北平原及其周围地区,这些地区污染物排放量大、空气质量较差;削减比例较大的地区主要集中在西部地区以及北京、天津2个直辖市,这些地区单位GDP能耗高、工业污染物去除率低、空气质量差;削减量相对较小的地区主要集中在西南和南部一些省份;削减比例较小的地区主要集中在中南部和南部几个省份,这些地区污染物排放量相对较少,空气质量好于其他省份。     

An algorithm to retrieve precipitation with synthetic aperture radar

This paper presents a new type of rainfall retrieval algorithm, called the model-oriented statistical and Volterra integration. It is a combination of the model-oriented statistical (MOS) and Volterra integral equation (VIE) approaches. The steps involved in this new algorithm can be briefly illustrated as follows. Firstly, information such as the start point and width of the rain is obtained through pre-analysis of the data received by synthetic aperture radar (SAR). Secondly, the VIE retrieval algorithm is employed over a short distance to obtain information on the shape of the rain. Finally, the rain rate can be calculated by using the MOS retrieval algorithm. Simulation results show that the proposed algorithm is effective and simple, and can lead to time savings of nearly 50% compared with MOS. An example of application of SAR data is also discussed, involving the retrieval of precipitation information over the South China Sea.