通过理论分析与原位实验,研究三维电学监测系统对垃圾填埋场多渗漏点位置的检测能力,分析影响检测效果的主要因素,以为设计经济、合理、有效的实时监测系统提供依据。结果表明:膜下电位监测法具有清晰的理论基础;供电电流强弱只影响测量电位值大小,不改变其异常形态,供电强度应以保证测量电位具有较高信噪比为原则;电极系极距大小会影响对相邻漏洞的检测能力,当极距小于相邻漏洞间距时,系统可对漏点位置进行有效反映;供电
Vector-to-raster conversion is a process accompanied with errors.The errors are classified into predicted errors before rasterization and actual errors after that.Accurate prediction of the errors is
Regional inequality is a core issue in geography,and it can be measured by several approaches and indexes.However,the global inequality measures can not reflect regional characteristics in terms of sp
From 27th to 29th, May, 2011, the participants of the 2nd International Forum on Geoparks from 5 countries gathered in Taining, Fujian Province, China. The participants discussed developing and preser
The 32nd International Geographical Congress (IGC) was held on August 26-30 in Cologne, Germany. About 3000 geographers from countries and regions across the world participated in the IGC, which cause
通过湿沙表面风沙传输的风洞实验,研究了湿润海岸风沙流的垂直结构、输沙率随风速与表层湿度的变化规律。输沙测量使用60cm高直立式积沙仪,湿度(M)为沙面表层1mm厚的重量湿度值。结果表明,湿沙表面的输沙量和高度呈指数关系。一般,湿度增大,整体输沙率降低,高湿度床面的沙粒有相对更大的比例被传输到更高的位置。比起低湿度(M<0.587%)沙粒,高湿度(0.587%
通过莫高窟窟顶野外风洞实验对不同覆盖度砾石床面风速梯度的变化规律进行了研究。结果表明,床面砾石平均高度以下风速梯度随砾石覆盖度变化比较杂乱,而砾石平均高度以上风速梯度随覆盖度增加呈现出有规律的变化。从覆盖度5%到35%风速逐渐减小,40%～80%趋于稳定,35%最小。据此,大气边界层可明显分为两层,约以砾石平均高度为界,下层定义为粗糙亚层,上层定义为惯性亚层。粗糙亚层风速梯度随砾石间距高度比D/H
This study examined whether prolonged residence in the Antarctica had a significant impact on cognitive performance.Participants were members of the 24th and 25th Chinese National Antarctic Research E
测绘是通过计算机技术、光学技术、空间技术、地理科学以及网络通信技术为基础,以GPS定位技术、遥感技术、卫星技术为核心的技术整合,将所测量地面的地形特征和基准点以数字图像和数字信息的形式模拟出来,以供工程施工的规划设计和行政工作使用。本文结合实际情况,通过对当前测绘工程中采用的新仪器、新技术的特点进行客观分析,提出积极的技术措施,以供交流和探讨。