The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precisio...The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precision.To ensure its accuracy of detection,it is necessary to correlate their thermal models to in-orbit da⁃ta.In this work,an investigation of intelligent correlation method named Intelligent Correlation Platform for Ther⁃mal Model(ICP-TM)was established,the advanced Kriging surrogate model and efficient adaptive region opti⁃mization algorithm were introduced.After the correlation with this method for FY-3E/HIRAS-Ⅱ,the results indi⁃cate that compared with the data in orbit,the error of the thermal model has decreased from 5 K to within±1 K in cold case(10℃).Then,the correlated model is validated in hot case(20℃),and the correlated model exhibits good universality.This correlation precision is also much superiors to the general ones like 3 K in other similar lit⁃erature.Furthermore,the process is finished in 8 days using ICP-TM,the efficiency is much better than 3 months based on manual.The results show that the proposed approach significantly enhances the accuracy and efficiency of thermal model,this contributes to the precise thermal control of subsequent infrared optical payloads.展开更多
In the present study,thermal behavior and crystal transition of pure poly(butylene adipate)(PBA)upon heating process were investigated by FTIR spectroscopy.To gain further insight into the thermal behavior alteration ...In the present study,thermal behavior and crystal transition of pure poly(butylene adipate)(PBA)upon heating process were investigated by FTIR spectroscopy.To gain further insight into the thermal behavior alteration and the phase transition of PBA,we performed two-dimensional(2D)correlation analysis.We found thatβ-form PBA crystal undergoes not only the melting process but also crystal transition upon the heating process.展开更多
A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including...A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including some of the very recent developments,is reviewed with examples.Topics include merged or modified asynchronous 2Dcorrelation spectrum,two-dimensional codistribution spectroscopy(2DCDS),Pareto scaling,and null-space projection treatment of spectral dataset.展开更多
A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensi...A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%.展开更多
Time resolution of multipath delay profiles measured by using autocorrelation of pseudonoise (PN) code sequence is generally limited by the chip rate of the PN code sequence. In this paper, we propose a simple method ...Time resolution of multipath delay profiles measured by using autocorrelation of pseudonoise (PN) code sequence is generally limited by the chip rate of the PN code sequence. In this paper, we propose a simple method to improve the time resolution of delay profiles measured by the PN correlation method. Effectiveness of this method is demonstrated by indoor wireless propagation experiments.展开更多
交叉熵法可显著加速电网可靠性评估,但往往聚焦于独立随机变量,若将其拓展至相关性变量可进一步提升加速性能。为有效获取相关性变量的重要抽样密度函数以实现其重要抽样,针对相关性建模中广泛使用的核密度估计模型(kernel density esti...交叉熵法可显著加速电网可靠性评估,但往往聚焦于独立随机变量,若将其拓展至相关性变量可进一步提升加速性能。为有效获取相关性变量的重要抽样密度函数以实现其重要抽样,针对相关性建模中广泛使用的核密度估计模型(kernel density estimation,KDE)开展了交叉熵优化研究。因KDE模型不属于指数分布家族,传统交叉熵优化难以实施,故利用复合抽样算法特点提出了新颖的直接交叉熵优化方法,推导出KDE模型最优权重参数的解析表达式。因权重参数数量级较小,直接优化易导致准确性退化,故基于子集模拟思想进一步提出间接交叉熵优化方法,将较小的权重参数优化转换成较大的条件概率优化,提升了优化准确性。通过MRTS79和MRTS96可靠性测试系统的评估分析,验证了所提方法在含相关性变量电网可靠性评估中的高效加速性能。展开更多
为快速、准确预测接触网复合绝缘子临界污闪电压,减少人工污秽试验工作量,提出了一种复合绝缘子污秽闪络电压预测模型。首先,利用黄金正弦(golden sine algorithm,GSA)与分段线性混沌映射(piecewise linear chaotic map,PWLCM)改进的减...为快速、准确预测接触网复合绝缘子临界污闪电压,减少人工污秽试验工作量,提出了一种复合绝缘子污秽闪络电压预测模型。首先,利用黄金正弦(golden sine algorithm,GSA)与分段线性混沌映射(piecewise linear chaotic map,PWLCM)改进的减法平均优化器(subtraction average based optimizer,SABO)算法增强反向传播(back propagation,BP)神经网络的性能;其次,利用人工污秽试验获取10种不同复合绝缘子的闪络电压,收集相关试验参数;再次,依据Obenaus模型对复合绝缘子污秽闪络表现进行分析,利用斯皮尔曼(Spearman)相关系数法筛选出与复合绝缘子临界污闪电压密切相关的4个参数作为预测模型的输入特征量,以预测复合绝缘子临界污闪电压;最后,利用五折交叉验证法对预测模型进行综合评估,并与常用智能优化算法预测模型的预测结果进行比较。结果表明:GSABO-BP模型预测复合绝缘子污闪电压平均绝对误差为1.244 kV,平均绝对百分比误差为2.25%,模型可决系数稳定在0.98以上;与改进前的SABO-BP模型相比,预测值平均误差下降67.80%。GSABO-BP模型在复合绝缘子污闪电压预测上具有较高的预测精准度,对电气化铁路供电系统的防污保护工作具有重要意义。展开更多
基金Supported by the National Key Research and Development Program of China(2022YFB3904803)。
文摘The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precision.To ensure its accuracy of detection,it is necessary to correlate their thermal models to in-orbit da⁃ta.In this work,an investigation of intelligent correlation method named Intelligent Correlation Platform for Ther⁃mal Model(ICP-TM)was established,the advanced Kriging surrogate model and efficient adaptive region opti⁃mization algorithm were introduced.After the correlation with this method for FY-3E/HIRAS-Ⅱ,the results indi⁃cate that compared with the data in orbit,the error of the thermal model has decreased from 5 K to within±1 K in cold case(10℃).Then,the correlated model is validated in hot case(20℃),and the correlated model exhibits good universality.This correlation precision is also much superiors to the general ones like 3 K in other similar lit⁃erature.Furthermore,the process is finished in 8 days using ICP-TM,the efficiency is much better than 3 months based on manual.The results show that the proposed approach significantly enhances the accuracy and efficiency of thermal model,this contributes to the precise thermal control of subsequent infrared optical payloads.
文摘In the present study,thermal behavior and crystal transition of pure poly(butylene adipate)(PBA)upon heating process were investigated by FTIR spectroscopy.To gain further insight into the thermal behavior alteration and the phase transition of PBA,we performed two-dimensional(2D)correlation analysis.We found thatβ-form PBA crystal undergoes not only the melting process but also crystal transition upon the heating process.
文摘A number of useful techniques associated with two-dimensional correlation spectroscopy(2DCOS)to improve its performance and utility have been developed in the last 30years.Evolution of these 2DCOS techniques,including some of the very recent developments,is reviewed with examples.Topics include merged or modified asynchronous 2Dcorrelation spectrum,two-dimensional codistribution spectroscopy(2DCDS),Pareto scaling,and null-space projection treatment of spectral dataset.
文摘A series of soy protein isolate(SPI)films plasticized by glycerol(Gly)were studied using attenuated total reflectance-Fourier transform infrared spectroscopy(ATR/FTIR).Perturbation-correlation movingwindow two-dimensional(PCMW2D)and two-dimensional correlation(2DCOS)analyses were applied to the amideⅠband and thus the hydrogen bond interaction between SPI and Gly was systematically investigated.When Gly concentrations were in the range 0~35%,the hydrogen bond amongβ-sheets was replaced by the one between SPI chain and Gly molecule,which caused these protein chains being changed toα-helix.However,the transformation ofβ-sheet toα-helix was saturated and both of them tend to change to random coil when Gly concentrations were in the range 35%~60%.
文摘Time resolution of multipath delay profiles measured by using autocorrelation of pseudonoise (PN) code sequence is generally limited by the chip rate of the PN code sequence. In this paper, we propose a simple method to improve the time resolution of delay profiles measured by the PN correlation method. Effectiveness of this method is demonstrated by indoor wireless propagation experiments.
文摘交叉熵法可显著加速电网可靠性评估,但往往聚焦于独立随机变量,若将其拓展至相关性变量可进一步提升加速性能。为有效获取相关性变量的重要抽样密度函数以实现其重要抽样,针对相关性建模中广泛使用的核密度估计模型(kernel density estimation,KDE)开展了交叉熵优化研究。因KDE模型不属于指数分布家族,传统交叉熵优化难以实施,故利用复合抽样算法特点提出了新颖的直接交叉熵优化方法,推导出KDE模型最优权重参数的解析表达式。因权重参数数量级较小,直接优化易导致准确性退化,故基于子集模拟思想进一步提出间接交叉熵优化方法,将较小的权重参数优化转换成较大的条件概率优化,提升了优化准确性。通过MRTS79和MRTS96可靠性测试系统的评估分析,验证了所提方法在含相关性变量电网可靠性评估中的高效加速性能。
文摘为快速、准确预测接触网复合绝缘子临界污闪电压,减少人工污秽试验工作量,提出了一种复合绝缘子污秽闪络电压预测模型。首先,利用黄金正弦(golden sine algorithm,GSA)与分段线性混沌映射(piecewise linear chaotic map,PWLCM)改进的减法平均优化器(subtraction average based optimizer,SABO)算法增强反向传播(back propagation,BP)神经网络的性能;其次,利用人工污秽试验获取10种不同复合绝缘子的闪络电压,收集相关试验参数;再次,依据Obenaus模型对复合绝缘子污秽闪络表现进行分析,利用斯皮尔曼(Spearman)相关系数法筛选出与复合绝缘子临界污闪电压密切相关的4个参数作为预测模型的输入特征量,以预测复合绝缘子临界污闪电压;最后,利用五折交叉验证法对预测模型进行综合评估,并与常用智能优化算法预测模型的预测结果进行比较。结果表明:GSABO-BP模型预测复合绝缘子污闪电压平均绝对误差为1.244 kV,平均绝对百分比误差为2.25%,模型可决系数稳定在0.98以上;与改进前的SABO-BP模型相比,预测值平均误差下降67.80%。GSABO-BP模型在复合绝缘子污闪电压预测上具有较高的预测精准度,对电气化铁路供电系统的防污保护工作具有重要意义。
