The Research On The Application Of Isomap In The Near Infrared Spectrum Online Determination Of Traditional Chinese Medicine

Quality control is the core issue of the modernization of Traditional ChineseMedicine (TCM). The currently used fingerprint techniques cannot be used in theonline quality control for its long analysis time. Fortunately, the techniques of nearinfrared (NIR) can be adopted for its short analysis time and its ability to re?ect thephysical abilities of the analytes.Modeling methods of NIR spectra were mainly studied in this dissertation. Fore-casting calibration models were set up between o?ine NIR spectra and reference valuesof the fingerprints and the information of the online products. First, a software wasdeveloped based on Visual C++ and the commonly used modeling algorithm -partialleast squares (PLS). This software possessed various methods for spectra pretreatmentas well as wavelength selection, and can be used in both o?ine and online modeling.More importantly, manifold learning was introduced into the NIR modeling for thenonlinear relations between NIR spectra, and some improvements were made.Manifold learning algorithms are kinds of novelly promoted nonlinear methodsfor dimension reduction, which can e?ectively find out the intrinsic low dimensionalstructure from high dimensional data. One of these algorithms -Isometric mapping(Isomap) was studied and improved in this dissertation, which was introduced intoNIR modeling. First, some expansions were made to Isomap. That is, kIsomap methodwas established after the introducing of Kernel function; dIsomap could select numberof the neighbor points according to the density of sample distribution; kdIsomap wasformed after integrating kIsomap and dIsomap. Then a nonlinear modeling mothedwas put forward by combining Isomap algorithms and PLS. In the method, Isomapalgorhthms were used to reduce the dimensions of the high dimensional NIR spectraldata. PLS was used to dimension reducing and modeling by succession. Finally, allthe methods were applied to two public benchmark NIR datasets and modeling. Andresults showed that the modeling methods were better than PLS.Isomap is an important nonlinear algorithm for dimension reduction, but cannotbe used to process new samples and therefore cannot serve as a supervised learningalgorithm. Based on the capability of Kernel Isomap to process new samples, therelations exist between Isomap and KPCA as well as the relations exist between KPCAand KPCR, a new method -superviese Isomap (SKIsomap), which can be applied tonew samples and regression was put forward and applied to correlate the NIR spectrawith the concentrations of chrysophenine and icariin in the extraction of Anshen BunaoYe.The other two algorithms of manifold learning algorithms were also studied in this dissertation, namely locally linear embedding (LLE) and Laplacian Regularized LeastSquares (LapRLS). LLE-PLS and LapRLS regression were put forward. And it wasapplied to correlate the NIR spectra with the concentrations of salvia acid B in theelution of column chromatography of Salvianolate.The techniques of TCM fingerprint, NIR online determination, manifold learn-ing algorithms and auto-control were integrated and applied to TCM manufacture inthis study, and actualized the real-time monitoring and online control of the chemi-cal components in the medicine, consequently guarantee the uniformity, stability andcontrollability of the product quality.