A Target Tracking System for Applications in Hydraulic Engineering

A new type of digital video monitoring system (DVMS) named user defined target tracking system (UDTTS), was developed based on the digital image processing (DIP) technology and the practice demands of construction site management in hydraulic engineering. The position, speed, and track of moving targets such as humans and vehicles, which could be calculated by their locations at anytime in images basically, were required for management. The proposed algorithm, dependent on the context-sensitive moving information of image sequences which was much more than one or two images provided, compared the blobs’ properties in current frame to the trajectories of targets in the previous frames and then corresponded them. The processing frame rate is about 10fps with the image 240-by-120 pixels. Experimental results show that position, direction, and speed measurements have an accuracy level compatible with the manual work. The user-define process makes the UDTTS available to the public whenever appropriate.     

基于视觉信息的堆石质量评价

为解决堆石混凝土(RFC)施工现场依靠人工巡视目测堆石质量的方法的不足,该文提出了一种用于堆石仓面质量管理的方法。该方法首先在施工现场采集堆石仓面的图像;其次对堆石图像上的视觉信息进行分析处理,为解决数字图像上石块间重叠、接触给石块识别带来的困难,应用分水岭算法实现块石的识别,进而提取块石粒径;最后得到堆石的级配曲线,从而对堆石仓面的质量进行等级评价。对在施工现场拍摄的堆石图像进行处理,将自动识别的块石粒径分布和人工识别的结果进行比较,验证了文中石块分割算法的准确性。该方法是一种非接触式、客观、便捷的用于堆石仓面质量管理的方法,可以应用于工程实践。     

基于增强现实的混凝土坍落扩展度测量

坍落扩展度是评价自密实混凝土工作性能的重要指标。该文提出了一种基于增强现实技术和智能手机平台的混凝土坍落扩展度测量方法。首先在扩展后的混凝土旁放置预定义标识;然后用手机的摄像头拍摄自密实混凝土的图像;接下来用图像处理技术求解手机与标识所在平面的相对位置;最后由用户在手机屏幕上指定需要测量线段的始末位置,进而计算出线段的实际距离。通过一系列坍落扩展度试验对该文方法进行了验证。试验结果表明:该文方法可以准确测量两点间的距离,测量结果与传统结果一致,适用于SCC坍落扩展度测量,是一种简便、实用的测量工具。