目的为解决疲劳驾驶检测中人眼状态识别的难点,提出一种基于眼白分割的疲劳检测方法。方法首先对获取图像进行人脸检测,利用眼白在Cb-Cr上良好的聚类性,基于YCb Cr颜色空间建立高斯眼白分割模型;然后在人脸区域图像内做眼白分割,计算眼...目的为解决疲劳驾驶检测中人眼状态识别的难点,提出一种基于眼白分割的疲劳检测方法。方法首先对获取图像进行人脸检测,利用眼白在Cb-Cr上良好的聚类性,基于YCb Cr颜色空间建立高斯眼白分割模型;然后在人脸区域图像内做眼白分割,计算眼白面积;最后将眼白面积作为人眼开度指标,结合PERCLOS(percentage of eyelid closure over the pupil over time)判定人的疲劳状态。结果选取10个短视频进行采帧分析,实验结果表明,高斯眼白分割模型能有效分离眼白,并识别人眼开合状态,准确率可达96.77%。结论在良好光线条件下,本文方法能取得不错的分割效果;本文所提出的以眼白面积作为判定人眼开度的指标,能准确地判定人的疲劳状态。实验结果证明了该方法的有效性,值得今后做更深入的研究。展开更多
While pre-deformation is often conducted before aging treatment to increase the strength and microhardness of 2195 Al-Li alloy, it often increases the fatigue crack growth(FCG) rate and thus reduces the fatigue life o...While pre-deformation is often conducted before aging treatment to increase the strength and microhardness of 2195 Al-Li alloy, it often increases the fatigue crack growth(FCG) rate and thus reduces the fatigue life of the alloy.To determine the effects and causes of pre-deformation and heat treatment on the mechanical properties and FCG rate of2195 Al-Li alloy, and to provide a suitable calculation model for the FCG rate under different pre-deformation conditions, 2195 Al-Li alloy specimens with different degrees of pre-rolling(0, 3%, 6%, and 9%) were investigated. The experimental results indicate that with the increase of pre-rolling, the density of the T1phase and the uniformity of the S′distribution and the microhardness, tensile strength, and yield strength of the alloy increase and at the same time the FCG rate increases, and thus the fatigue life is reduced. It was also found that the normalized stress intensity factor of elastic modulus(E) can be applied to correlate the FCG rate of pre-rolled 2195 Al-Li alloy with constant C and K parameters.展开更多
文摘目的为解决疲劳驾驶检测中人眼状态识别的难点,提出一种基于眼白分割的疲劳检测方法。方法首先对获取图像进行人脸检测,利用眼白在Cb-Cr上良好的聚类性,基于YCb Cr颜色空间建立高斯眼白分割模型;然后在人脸区域图像内做眼白分割,计算眼白面积;最后将眼白面积作为人眼开度指标,结合PERCLOS(percentage of eyelid closure over the pupil over time)判定人的疲劳状态。结果选取10个短视频进行采帧分析,实验结果表明,高斯眼白分割模型能有效分离眼白,并识别人眼开合状态,准确率可达96.77%。结论在良好光线条件下,本文方法能取得不错的分割效果;本文所提出的以眼白面积作为判定人眼开度的指标,能准确地判定人的疲劳状态。实验结果证明了该方法的有效性,值得今后做更深入的研究。
基金Project(U21A20132) supported by the National Natural Science Foundation of ChinaProject(Gui Renzi2019(13))supported by the Guangxi Specially-invited Experts Foundation of Guangxi Zhuang Autonomous Region,China。
文摘While pre-deformation is often conducted before aging treatment to increase the strength and microhardness of 2195 Al-Li alloy, it often increases the fatigue crack growth(FCG) rate and thus reduces the fatigue life of the alloy.To determine the effects and causes of pre-deformation and heat treatment on the mechanical properties and FCG rate of2195 Al-Li alloy, and to provide a suitable calculation model for the FCG rate under different pre-deformation conditions, 2195 Al-Li alloy specimens with different degrees of pre-rolling(0, 3%, 6%, and 9%) were investigated. The experimental results indicate that with the increase of pre-rolling, the density of the T1phase and the uniformity of the S′distribution and the microhardness, tensile strength, and yield strength of the alloy increase and at the same time the FCG rate increases, and thus the fatigue life is reduced. It was also found that the normalized stress intensity factor of elastic modulus(E) can be applied to correlate the FCG rate of pre-rolled 2195 Al-Li alloy with constant C and K parameters.
