A novel thickness measurement method for surface insulation coating of silicon steel based on NIR spectrometry is explored.The NIR spectra of insulation coating of silicon steel were collected by acousto-optic tunable...A novel thickness measurement method for surface insulation coating of silicon steel based on NIR spectrometry is explored.The NIR spectra of insulation coating of silicon steel were collected by acousto-optic tunable filter(AOTF) NIR spectrometer.To make full use of the effective information of NIR spectral data,discrete binary particle swarm optimization(DBPSO) algorithm was used to select the optimal wavelength variates.The new spectral data,composed of absorbance at selected wavelengths,were used to create the thickness quantitative analysis model by kernel partial least squares(KPLS) algorithm coupled with Boosting.The results of contrast experiments showed that the Boosting-KPLS model could efficiently improve the analysis accuracy and speed.It indicates that Boosting-KPLS is a more accurate and robust analysis method than KPLS for NIR spectral analysis.The maximal and minimal absolute error of 30 testing samples is respectively-0.02 μm and 0.19 μm,and the maximal relative error is 14.23%.These analysis results completely meet the practical measurement need.展开更多
High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating...High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating characters of laser damage, including determination of laser induced damage threshold and detection of absorption based on surface thermal lensing technique. Defect was deemed to be the initial source of laser damage, and was the main factor restricting the laser damage resistance of optical coatings. The contribution of several kinds of typical defects to laser damage was analyzed, and some deposition measures were adopted to control and eliminate the origin of defect. Furthermore, some post-treatment methods were also employed to alleviate the influence of the defect and to improve the laser damage resistance. Correction mask was introduced to improve the thickness uniformity, and the thickness uniformity can be amended to less than 1% in the range of Φ650 mm. Preliminary investigation related to surface deformation was also conducted.展开更多
针对涂层提高旋耕刀耐磨性但会增加作业功耗的问题,该研究通过仿真与试验探究了不同厚度涂层对旋耕刀功耗的影响规律,并优选了涂层厚度。通过仿真模拟旋耕刀作业过程,得到旋耕刀易磨损位置和涂层厚度对旋耕刀功耗的影响规律。采用等离...针对涂层提高旋耕刀耐磨性但会增加作业功耗的问题,该研究通过仿真与试验探究了不同厚度涂层对旋耕刀功耗的影响规律,并优选了涂层厚度。通过仿真模拟旋耕刀作业过程,得到旋耕刀易磨损位置和涂层厚度对旋耕刀功耗的影响规律。采用等离子堆焊技术制备1、1.5和2 mm 3种厚度耐磨涂层,并进行田间功耗测试。田间试验结果发现,随旋耕刀涂层厚度由0增至1、1.5、2 mm,平均功耗分别增加了12.4%、17.3%和26.8%,旋耕刀功耗随涂层厚度变化趋势与仿真试验一致,误差范围在0.17%~6.77%之间,验证了仿真模型的准确性,并根据旋耕作业仿真过程分析了涂层导致旋耕刀功耗增长的原因。基于成本分析与涂层耐磨性及其对功耗的影响,确定旋耕刀涂层强化最优厚度为1.25 mm。该研究得到了涂层对旋耕刀功耗影响机制,提出了综合成本、功耗与耐磨性选择涂层厚度的方法,可为旋耕刀涂层强化工艺厚度选择提供理论基础。展开更多
针对碳纤维复合材料涂层厚度检测问题,进行了综合性实验设计。提出结合L1范数的谱投影梯度算法(spectral projection gradient based L1,SPGL1)的涂层厚度检测方法,结合涂层测厚实际,明确了基底检测更适合使用反射式太赫兹时域系统。分...针对碳纤维复合材料涂层厚度检测问题,进行了综合性实验设计。提出结合L1范数的谱投影梯度算法(spectral projection gradient based L1,SPGL1)的涂层厚度检测方法,结合涂层测厚实际,明确了基底检测更适合使用反射式太赫兹时域系统。分析求解了凸最优问题需要的条件,给出了信号稀疏分解结合飞行时间法的涂层厚度检测方案。实验数据表明,当涂层折射率相差较大时,加入噪声后的结果与理想情况一致,当涂层折射率相近时,SPGL1方法具有良好的抗干扰能力。该实验基于教师科研成果,通过完整的实验设计能够帮助学生理解时域光谱、稀疏分解、飞行时间法等基本理论和方法,锻炼了学生的实践动手能力和知识综合运用能力,培养了探索热情和创新意识。展开更多
基金National High Technology Research and Development Program of China(2009AA04Z131)Natural Science Foundation of China (50877056)
文摘A novel thickness measurement method for surface insulation coating of silicon steel based on NIR spectrometry is explored.The NIR spectra of insulation coating of silicon steel were collected by acousto-optic tunable filter(AOTF) NIR spectrometer.To make full use of the effective information of NIR spectral data,discrete binary particle swarm optimization(DBPSO) algorithm was used to select the optimal wavelength variates.The new spectral data,composed of absorbance at selected wavelengths,were used to create the thickness quantitative analysis model by kernel partial least squares(KPLS) algorithm coupled with Boosting.The results of contrast experiments showed that the Boosting-KPLS model could efficiently improve the analysis accuracy and speed.It indicates that Boosting-KPLS is a more accurate and robust analysis method than KPLS for NIR spectral analysis.The maximal and minimal absolute error of 30 testing samples is respectively-0.02 μm and 0.19 μm,and the maximal relative error is 14.23%.These analysis results completely meet the practical measurement need.
文摘High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating characters of laser damage, including determination of laser induced damage threshold and detection of absorption based on surface thermal lensing technique. Defect was deemed to be the initial source of laser damage, and was the main factor restricting the laser damage resistance of optical coatings. The contribution of several kinds of typical defects to laser damage was analyzed, and some deposition measures were adopted to control and eliminate the origin of defect. Furthermore, some post-treatment methods were also employed to alleviate the influence of the defect and to improve the laser damage resistance. Correction mask was introduced to improve the thickness uniformity, and the thickness uniformity can be amended to less than 1% in the range of Φ650 mm. Preliminary investigation related to surface deformation was also conducted.
文摘针对涂层提高旋耕刀耐磨性但会增加作业功耗的问题,该研究通过仿真与试验探究了不同厚度涂层对旋耕刀功耗的影响规律,并优选了涂层厚度。通过仿真模拟旋耕刀作业过程,得到旋耕刀易磨损位置和涂层厚度对旋耕刀功耗的影响规律。采用等离子堆焊技术制备1、1.5和2 mm 3种厚度耐磨涂层,并进行田间功耗测试。田间试验结果发现,随旋耕刀涂层厚度由0增至1、1.5、2 mm,平均功耗分别增加了12.4%、17.3%和26.8%,旋耕刀功耗随涂层厚度变化趋势与仿真试验一致,误差范围在0.17%~6.77%之间,验证了仿真模型的准确性,并根据旋耕作业仿真过程分析了涂层导致旋耕刀功耗增长的原因。基于成本分析与涂层耐磨性及其对功耗的影响,确定旋耕刀涂层强化最优厚度为1.25 mm。该研究得到了涂层对旋耕刀功耗影响机制,提出了综合成本、功耗与耐磨性选择涂层厚度的方法,可为旋耕刀涂层强化工艺厚度选择提供理论基础。
文摘针对碳纤维复合材料涂层厚度检测问题,进行了综合性实验设计。提出结合L1范数的谱投影梯度算法(spectral projection gradient based L1,SPGL1)的涂层厚度检测方法,结合涂层测厚实际,明确了基底检测更适合使用反射式太赫兹时域系统。分析求解了凸最优问题需要的条件,给出了信号稀疏分解结合飞行时间法的涂层厚度检测方案。实验数据表明,当涂层折射率相差较大时,加入噪声后的结果与理想情况一致,当涂层折射率相近时,SPGL1方法具有良好的抗干扰能力。该实验基于教师科研成果,通过完整的实验设计能够帮助学生理解时域光谱、稀疏分解、飞行时间法等基本理论和方法,锻炼了学生的实践动手能力和知识综合运用能力,培养了探索热情和创新意识。
