In this work, we propose a new scheme to generate frequency-doubled vortex beams from a radially poled LiNbO3 micro-ring resonator based on nonlinear Cherenkov radiation. The near-infrared fundamental wave is resonant in the micro-ring, while t
It is a dream of worldwide scientists to demonstrate fusion ignition and gain in the laboratory. The demonstration of laboratory fusion ignition via Inertial Confinement Fusion (ICF) will allow scientists to understand processes in the cores of stars, to
We employ the in-site automated observation radiometric calibration (AORC) approach to perform vicarious calibration, which does not require the manual efforts of a field team to measure the surface conditions. By using an automated test-
基于BOF(Bag of features)图像检索算法对电气设备图像进行分类,首先,通过加速鲁棒特征(SURF)算法寻找特征点位置,构造高维特征描述算子对特征进行描述和统计。然后,利用K-means聚类算法处理特征描述算子,得到独立的视觉词汇并汇总为特定数目的码书。将码书中的特征描述算子进行量化和加权统计,用特征向量直方图表示整个图像。最后,用训练集图像的高维特征向量进行机器学习,对未知图像进行