Visualization of Vector Tiles on CesiumJS Virtual Globe

Essentially, CesiumJS—which can be accessed through the link, http://cesiumjs.org, is an open-source JavaScript library for creating virtual globe environment in performance effective, high quality of rendering, precision, and user friendly. It is a wonderful tool for 3D-themed visualizations of earth. CesiumJS has a number of data sources, but none of them supports vector tile format. This article explains how to visualize Mapbox vector tiles in a CesiumJS virtual globe environment. CartoDB/BigQuery hosts vector tiles, and a process for producing vector tiles from massive vector data using the BigQuery tiler of CartoDB has been provided.

基于遗传算法局部方向梯度的古墓葬圆形土壤标志检测(英文)

中国新疆北部古墓葬目标在Google Earth上显示为两大类:一类是斑点型,另一类是圆环型,两类的边界都比较模糊。自动提取这些古墓葬目标比较困难,针对这一问题,提出了一种基于遗传算法局部方向梯度的圆形检测算法。该方法采用局部方向梯度,并且基于计算边缘方向梯度的主分量实现,因此该方法能适用各种边缘特征,遗传算法的加入能够提高在圆形不连贯、多圆相交等情况下圆形自动检测的鲁棒性。本文选取新疆北部作为试验区域,结果表明本文方法与传统的基于霍夫变换的圆形检测算法相比,能适应多特征的圆形边缘,而且不用设定自动检测中的阈值,更加智能化,自动化。