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Observation of the 532 nm-laser-induced fluorescence spectra of two kinds of Cr:Mg2SiO4 crystalline samples grown in different atomsphere are reported. The experiments were con-ducted at both room temperature and liquid-nitrogen temperature. The fluorescence spectra of the two kinds of samples were different with respect to the polarizing direction of the inducing leser, and two emission bands with different polarized characters and various en-hancement in intensity at low temperatures were also found. In the light of the calculated results by Ms-Xα method, the main experimental results are explained. 相似文献
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针对海空复杂背景下红外小目标识别的需要,对海空背景及其小目标的红外图像特性进行了统计分析。具体分析了在有目标和无目标两种情况下3~5 μm和8~12 μm两个波段图像的均值、方差和协方差等统计特性以及图像的局部对比度、信杂比和阈值随探测距离变化的规律;同时对生成的红外热像进行了直方图分析。结果表明:随着探测距离的减小,导弹的辐射逐渐增大,到达一定探测距离时(大约8 200 m)可以从热像图中区分导弹的蒙皮辐射和羽流辐射。根据有目标和无目标两种情况下图像特性的差异,可以判断图像中是否存在目标,从而为目标识别提供了关于目标和背景的先验知识,研究结果可用于海空背景下红外小目标的检测。 相似文献
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Observation of the 532 nm-laser-induced fluorescence spectra of two kinds of Cr:Mg2SiO4 crystalline samples grown in different atomsphere are reported. The experiments were con-ducted at both room temperature and liquid-nitrogen temperature. The fluorescence spectra of the two kinds of samples were different with respect to the polarizing direction of the inducing leser, and two emission bands with different polarized characters and various en-hancement in intensity at low temperatures were also found. In the light of the calculated results by Ms-Xα method, the main experimental results are explained. 相似文献
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