基于机载多基线PolInSAR的森林冠层高度反演

以美国航空航天局(National Aeronautics and Space Administration,NASA)、欧洲航天局(European Space Agency,ESA)、加蓬航天局合作的AfriSAR项目中的Lopenp和Mondah为实验区,以L波段的多基线全极化无人驾驶飞行器合成孔径雷达(unmanned aerial vehicle synthetic aperture radar,UAVSAR)数据为数据源,分别采用高度偏差(height variance,VAR)方法、偏心率(eccentricity,ECC)方法和平均相干幅度与分离度乘积(product of average coherence magnitude and separation,PROD)方法、原点到拟合直线距离与分离度乘积(product of fitted line distance from origin and coherence separation,LINE)方法进行基线选择,并基于地面随机体散射模型(random volume on ground,RVoG)三阶段方法反演森林...     

蓝洞中的“外星”细菌群落

蓝洞,很简单,就是蓝色的洞穴,会自己发出神秘的蓝光。早在古罗马时期就记载有人探险蓝洞,结论竟然是巫婆修练＂葵花宝典＂的秘密基地,这使得蓝洞变得愈发的引人入胜。     

大型土木工程结构的动态位移远距离实时监测系统(英文)

Based on digital image processing technique, a real-time system is developed to monitor and detect the dynamic displacement of engineering structures. By processing pictures with a self-programmed software, the real-time coordinate of an object in a certain coordinate system can be obtained, and further dynamic displacement data and curve of the object can also be achieved. That is, automatic gathering and real-time processing of data can be carried out by this system simultaneously. For this system, first, an untouched monitoring technique is adopted, which can monitor or detect objects several to hundreds of meters apart; second, it has flexible installation condition and good monitoring precision of sub-millimeter degree; third, it is fit for dynamic, quasi-dynamic and static monitoring of large engineering structures. Through several tests and applications in large bridges, good reliability and dominance of the system is proved.     

光缆：潜伏海底，直击未来

屡败屡战的海底光缆铺设史有史以来第一条海底缆线是在1850年英法之间铺设的,由约翰·沃特金·布莱特的盎格鲁-法国电报公司开设了一条穿越英吉利海峡的电缆。那时候的电缆,制作非常粗糙,打个不恰当的比方,就像是随手用纸卷成的卷烟,没有其他任何保障。