猕猴桃膨大果的近红外漫反射光谱无损识别  

Identification of Expanded Kiwifruits by Near-infrared Diffused Spectroscopy

作　　者：郭文川[1] 刘大洋[1] 

机构地区：[1]西北农林科技大学机械与电子工程学院,陕西杨凌712100

出　　处：《农业机械学报》2014年第9期230-235,共6页Transactions of the Chinese Society for Agricultural Machinery

基　　金：国家自然科学基金资助项目(31171720)

摘　　要：在833-2500 nm光谱范围内采集了120个猕猴桃膨大果和120个正常果的近红外漫反射光谱,采用变量标准化方法对光谱进行了预处理,基于Kennard-Stone方法对样本进行了划分,分别建立了基于全光谱（FS）、主成分分析法（PCA）提取的11个主成分和连续投影算法（SPA）提取的6个特征波长的偏最小二乘（PLS）、支持向量机（SVM）和误差反向传播（BP）神经网络识别模型。结果说明,所建立的9个模型对校正集和测试集中猕猴桃膨大果和正常果的正确识别率均分别大于96.7%和93.3%。PCA提取的主成分数和SPA提取的特征波长数仅是FS中波长数的0.53%和0.29%,建立的模型更加简单,且识别效率较高。PLS和SVM模型的识别率普遍高于BP神经网络模型。9种模型中PCA-PLS识别率最高,其对校正集和测试集中膨大果和正常果的正确识别率均达到100%。该研究结果表明,近红外漫反射光谱技术可作为一种准确、高效的方法应用于猕猴桃膨大果的无损识别中。In order to develop a nondestructive method for identifying expanded kiwifruits, near-infrared diffused spectra of 120 expanded kiwifruits and 120 normal kiwifruits were obtained between 833 and 2 500 nm using a Fourier transformation near-infrared diffused spectrograph. Standard normal variate transformation was used to preprocess original spectra. The samples were divided into calibrationset and prediction set based on Kennard - Stone method. Eleven principal components and 6 characteristic wavelengths were selected by principal component analysis （PCA） and successive projections algorithm （SPA）. Partial least squares （ PLS）, support vector machine （ SVM）, and error back propagation （BP） neural network identification model were established based on full spectrum （FS）, PCA, and SPA, respectively. The results showed that correct identification rates of all models were higher than 96.7% and 93.3% for calibration set and predication set, respectively. The established models based on PCA and SPA were much simpler than those based on FS, since the variable numbers of them were only about 0.53% and 0. 29% of that of FS, respectively. The identification performance of PLS and SVM were better than that of BP. The best model was PCA - PLS, whose accuracy rate reached 100% for calibration set and predication set. The results clearly indicate that near-infrared diffused spectra technique has the potential as an efficient, accuracy and non-invasive method for distinguishing expanded kiwifruits from normal kiwifruits.

关 键 词：猕猴桃 膨大果 近红外光谱 识别 

分 类 号：O657.33[理学—分析化学] S663.4[理学—化学]