CAJ | 학술논문

针对现有用于光谱预处理的小波变换算法对光谱噪声和背景荧光等处理效果不佳的局限性,本文提出了一种改进的小波变换算法--小波变换频率分量相关选择法,首先对拉曼光谱进行小波棱镜分解,然后计算各个频率分量与待测质量指标的相关系数,设定相关系数的相对阈值,提取高于阈值的小波频率分量波长点光谱数据作为校正模型的有效输入数据.将其应用于汽油低分辨率拉曼光谱的预处理,并采用预处理后光谱建立的偏最小二乘模型预测值的最大正负误差和交叉检验的均方误差作为指标.实验结果证明,与其他常见预处理方法比较,该方法并能够很好地减弱荧光背景干扰和高频噪声,显著提高了基于偏最小二乘方法建立的汽油辛烷值的模型预测精度,其均方误差减少为0.23;此外,采用该预处理方法的偏最小二乘模型的均方误差随主元数变化不大,稳健性也比采用其他预处理方法的效果好.
침대현유용우광보예처리적소파변환산법대광보조성화배경형광등처리효과불가적국한성,본문제출료일충개진적소파변환산법--소파변환빈솔분량상관선택법,수선대랍만광보진행소파릉경분해,연후계산각개빈솔분량여대측질량지표적상관계수,설정상관계수적상대역치,제취고우역치적소파빈솔분량파장점광보수거작위교정모형적유효수입수거.장기응용우기유저분변솔랍만광보적예처리,병채용예처리후광보건립적편최소이승모형예측치적최대정부오차화교차검험적균방오차작위지표.실험결과증명,여기타상견예처리방법비교,해방법병능구흔호지감약형광배경간우화고빈조성,현저제고료기우편최소이승방법건립적기유신완치적모형예측정도,기균방오차감소위0.23;차외,채용해예처리방법적편최소이승모형적균방오차수주원수변화불대,은건성야비채용기타예처리방법적효과호.
To overcome the limitations of existing wavelet transform(WT)preprocessing methods for Raman spectra,such as bad performance on spectral noise and fluorescence,an improved preprocessing method-WT frequency component correlative selection algorithm was proposed.In this method,Raman spectra are firstly prism-decomposed by WT,then correlations between every frequent weight and target are computed and threshold is set to select the efficient input data for calibration model.This method is applied in gasoline Low-Resolution Raman spectra data preprocessing;the max positive/negative error and root mean squares error of cross validation(RMSECV)of the partial least square(PLS)model based on spectra after preprocessing is used to build are selected as criterion.Compared with other existing method,the experimental results show the new algorithm obviously weakens the fluorescence and high frequent noise and improves the prediction performance of the PLS model for gasoline octane number,the RMSECV can be reduce to 0.23;besides,the RMSECV of PLS model based on proposed method does not change dramatically along with the change of the latent number of PLS model.So this method is more robust than others.