Abstract
Near infrared(NIR) spectroscopy is a new chemical analysis method, with no pollution, no damage, rapid analysis, high efficiency, low cost and so on-line analysis can be achieved, in food, medicine, chemical industry, oil fields obtained unprecedented development, and its increasingly wide area involved. Therefore, this article on qualitative analysis by near infrared spectroscopy depth research, specifically including the following:
By a lot of reading in English and Chinese literature, the concept of near infrared spectroscopy, principles and application made a more systematic and complete exposition of the correction pattern recognition technology and quantitative methods in the near infrared analysis were careful to describe .
This will support vector machine (SVM) classification algorithm is successfully applied to the fast recognition of brands of gasoline. With other classification algorithms such as K-Nearest Neighbor (KNN), similar analysis (SIMCA) in the comparison shows that, SVM classification method was the best, the maximum classification error rate is very low, the results are stable and changes by the sample, the parameter changes have little effect, with a wide range of application.
In order to improve the accuracy of quantitative analysis, this paper presents a hybrid partial least squares (PartialLeastsquares, PLS) method. First, the test samples with svM method to classify, and then use a similar nature and applied to the sample part of the calibration samples similar model to predict property values tested. In order to overcome the impact of classification error samples, mixed PLS method contains the local PLS-based classification method and all the training set based on the local PLS method two algorithms. Mixed PLS method by comparing the output of two local PLS method to calculate the value of the tested samples tested property. Number of gas samples for experimental results show that the algorithm of the parameters of gasoline reached a high predictive accuracy.
Based on the above theoretical results, for the parameters of gasoline has been developed near-infrared spectrometer, and the proposed hybrid PLS Near Infrared Spectroscopy Quantitative Analysis of the parameters used in gasoline in the quantitative prediction to improve the performance of the instrument.