Laser shock peening is a well-known method for extending the fatigue life of metal components by introducing near-surface compressive residual stress. The surface acoustic waves (SAWs) are dispersive when the near-surface properties of materials are chang
Compared with traditional uniform fibers, tapered fiber has numerous unique advantages, such as larger mode area, higher pump absorption, suppression to nonlinear effects, and maintaining good beam quality. In this manuscript, we have constructed an all-f
Defect is built as that in the semiconductor when some metal posts are withdrawn regularly from the two-dimensional (2D) photonic crystal (PC) formed by triangular arrays of metal posts. Such defect can be used to design cavity. The relation among the lat
本文从离轴参考束全息图的基本方程出发,介绍了干涉型计算全息图。分析了宽条纹和窄条纹干涉型全息图的特点并给出了检验结果。指出了波差近似计算公式的适用范围。给出了三组实际检验结果。实验表明,(-1,0)和(0, 1)级波面的干涉图是相同的,并给出了解释。
为了实现对危化品仓储堆垛安全距离的实时监测和预警, 采用由激光测距、旋转云台、编码器等组成的激光扫描监控阵列对垛距进行安全监测。针对激光测距扫描点云数据中异常噪声的问题, 采用差值去噪算法。该算法是将扫描得到的激光测距数据点按角度值进行从小到大排序后, 相邻两点的距离值依次取差值, 然后对距离差值与预设阈值进行比较, 滤掉噪点数据。针对几种不同尺寸和形状的障碍物进行了实验研究, 结果表明差值去噪方差值明显小于加权二乘、Savitzky-Golay等拟合算法, 该算法不仅能有效去除扫描点云数据中的异常噪声,