采用车载激光雷达的带状地物矢量化与结构特征提取

针对车载激光点云带状地物形状多样、难以用规则语义信息矢量化,以及结构语义信息提取研究较少的问题,提出一种基于Ribbon Snake模型的车载激光雷达带状地物(道路边界、实线型标线、铁轨)矢量化与结构特征提取方法.首先,通过格网剖分构建点云特征图,利用Ribbon Snake模型提取带状地物矢量化数据;然后,分析不同道路和铁路场景的结构特征,生成具有准确几何和拓扑结构信息的三维矢量数据和属性数据.实验表明:该方法能够准确地提取带状地物矢量化与结构信息,实现不同场景下带状地物的有效完整描述.

带状地物控制点对高分一号影像几何校正精度的影响

遥感图像成图时,会受到各种因素的影响而产生几何变形。应用ENVI5.1平台并采用二次多项式模型分别基于9个、18个、24个地面控制点进行几何校正,校正后影像中线性地物相对误差差距不大。研究结果表明,增加带状地物控制点可以明显降低线性地物相对误差,提高校正精度。

TM卫片上带状地物面积误差研究

以 1∶2 .5万比例尺TM卫片为主要信息源进行二类调查 ,在内蒙古大兴安岭林区 ,已全面实行两年。由于TM卫片与基本图比例尺一致 ,且TM卫片为多中心投影 ,近似于垂直投影 ,图面精度可达 98 1%。但是 ,在TM卫片处理过程中 (线性拉伸 ,边缘增强等人为因素使带状地物 (河流、道路等 )宽度增加 ,造成卫片上带状地物面积误差较大 ,精度较低 ,从而影响二类调查质量。文章通过对毕拉河林业局境内河流、道路、带状林地转绘面积误差进行研究 ,找出误差规律性 ,以便在带状地物面积求算时加以调整 ,提高二类调查面积精度 ,从而保证二类调查质量。

无人机在带状地形监测方法中的应用研究

近几年来,无人机发展迅速,在稳定性、续航能力、自动化等方面都有了较大程度的进步。本文通过对无人机在某高速铁路航测项目作业方法的研究,充分显示了无人机在小面积测区机动、快速成图的特点。

P25 Scoring Method for the Assessment of R/C Buildings

An effective rapid assessment technique, called ＂P25 Scoring Method＂, has been developed and tested on 26 different case studies recently, in order to predict the collapse vulnerability of the R/C buildings. After a short description of the approach, the study presents the sensitivity study of the method to the selected structural parameters by considering incremental deviation of the final scores from the base model. Further, the methodology was applied to an additional 100 damaged buildings in order to check the reliability of the method and some necessary modifications have been applied to the algorithm after considering this larger database. The evaluation of the results has been interpreted as a beneficial guidance for local authorities. The risk bands are defined according to the final scores and the effect of changing the band-width has also been studied through a safe but an economical procedure. A satisfactory correlation of the method with real damage states is obtained and a ready-to-use methodology has been introduced for future studies.