近红外光谱法分析油页岩含油率中异常样品识别和剔除方法的研究  

Research on Outlier Detection Methods for Determination of Oil Yield in Oil Shales Using Near-Infrared Spectroscopy

作　　者：赵振英[1] 林君[1] 张怀柱[1] 

机构地区：[1]吉林大学仪器科学与电气工程学院,吉林长春130061

出　　处：《光谱学与光谱分析》2014年第6期1707-1710,共4页Spectroscopy and Spectral Analysis

基　　金：国家潜在油气资源(油页岩勘探开发利用)产学研用合作创新项目子课题(OSR-02-04)资助

摘　　要：研究了漫反射近红外(NIR)光谱法分析油页岩含油率过程中异常样品的识别和剔除方法。在近红外光谱定量分析中,环境变化和操作失误等都会产生异常样品,异常样品的存在会导致模型的预测能力下降,因此异常样品的剔除是建模过程中的关键步骤。分别采用主成分分析—马氏距离(PCA-MD)法和半数重采样(RHM)法识别油页岩光谱数据中的异常样品,通过剔除异常样品后所建的偏最小二乘(PLS)分析模型的性能来评价PCA-MD与RHM方法对异常样品的识别能力。实验中考察了不同MD阈值和RHM置信度对异常样品剔除结果的影响,比较了单独和同时应用PCA-MD及RHM法识别并剔除异常样品后所得PLS模型的预测能力。结果表明:与所有样品参与建模时预测偏差均方根(RMSEP)相比,采用PCA-MD法时阈值取平均值与标准偏差之和时RMSEP降低了48.3%;采用RHM法时置信度取85%时RMSEP降低了27.5%;同时采用PCA-MD法和RHM法时RMSEP降低了44.8%,研究内容有效地提高了分析模型的预测能力。In the present paper,the outlier detection methods for determination of oil yield in oil shale using near-infrared （NIR） diffuse reflection spectroscopy was studied.During the quantitative analysis with near-infrared spectroscopy,environmental change and operator error will both produce outliers.The presence of outliers will affect the overall distribution trend of samples and lead to the decrease in predictive capability.Thus,the detection of outliers are important for the construction of high-quality calibration models.The methods including principal component analysis-Mahalanobis distance （PCA-MD）and resampling by half-means （RHM）were applied to the discrimination and elimination of outliers in this work.The thresholds and confidences for MD and RHM were optimized using the performance of partial least squares （PLS）models constructed after the elimination of outliers,respectively.Compared with the model constructed with the data of full spectrum,the values of RMSEP of the mod-els constructed with the application of PCA-MD with a threshold of a value equal to the sum of average and standard deviation of MD,RHM with the confidence level of 85%,and the combination of PCA-MD and RHM,were reduced by 48. 3%,27. 5% and 44. 8%,respectively.The predictive ability of the calibration model has been improved effectively.

关 键 词：近红外光谱 异常样品剔除 油页岩 含油率 

分 类 号：O657.3[理学—分析化学]