光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2010年
2期
327-330
,共4页
可见/近红外光谱%独立分最分析%BP神经网络%遗传算法%土壤
可見/近紅外光譜%獨立分最分析%BP神經網絡%遺傳算法%土壤
가견/근홍외광보%독립분최분석%BP신경망락%유전산법%토양
Visible/near infrared spectroscopy(Vis/NIR)%Independent component analysis%BP neural networks%Genetic algorithm%Soil
为实现土壤中有机碳(TOC)含量和阳离子交换量(CEC)的快速检测,对300个土壤样品的可见/近红外光谱数据进行了分析.使用快速独立分量分析(FastICA)算法对光谱数据矩阵进行分解,得到独立成分和相应的混合系数矩阵,再利用误差反向传播算法(back-propagation,BP)构造三层神经网络结构.为了克服传统BP神经网络结构难以确定和易于陷入局部极小点的缺点,采用遗传算法优化BP神经网络结构和初始权值,得到ICA-GA-BP模型.利用此模型对土壤中TOC含量和CEC进行预测,根据预测相关系数(R~2)和预测标准偏差(RMSEP)来评价预测模型的性能,表明该模型对TOC含量和CEC测定的相关系数R~2均达到0.98以上.说明文章提出的ICA-GA-BP建模方法具有很好的预测效果,为土壤品质的鉴别提供了一种新方法.
為實現土壤中有機碳(TOC)含量和暘離子交換量(CEC)的快速檢測,對300箇土壤樣品的可見/近紅外光譜數據進行瞭分析.使用快速獨立分量分析(FastICA)算法對光譜數據矩陣進行分解,得到獨立成分和相應的混閤繫數矩陣,再利用誤差反嚮傳播算法(back-propagation,BP)構造三層神經網絡結構.為瞭剋服傳統BP神經網絡結構難以確定和易于陷入跼部極小點的缺點,採用遺傳算法優化BP神經網絡結構和初始權值,得到ICA-GA-BP模型.利用此模型對土壤中TOC含量和CEC進行預測,根據預測相關繫數(R~2)和預測標準偏差(RMSEP)來評價預測模型的性能,錶明該模型對TOC含量和CEC測定的相關繫數R~2均達到0.98以上.說明文章提齣的ICA-GA-BP建模方法具有很好的預測效果,為土壤品質的鑒彆提供瞭一種新方法.
위실현토양중유궤탄(TOC)함량화양리자교환량(CEC)적쾌속검측,대300개토양양품적가견/근홍외광보수거진행료분석.사용쾌속독립분량분석(FastICA)산법대광보수거구진진행분해,득도독립성분화상응적혼합계수구진,재이용오차반향전파산법(back-propagation,BP)구조삼층신경망락결구.위료극복전통BP신경망락결구난이학정화역우함입국부겁소점적결점,채용유전산법우화BP신경망락결구화초시권치,득도ICA-GA-BP모형.이용차모형대토양중TOC함량화CEC진행예측,근거예측상관계수(R~2)화예측표준편차(RMSEP)래평개예측모형적성능,표명해모형대TOC함량화CEC측정적상관계수R~2균체도0.98이상.설명문장제출적ICA-GA-BP건모방법구유흔호적예측효과,위토양품질적감별제공료일충신방법.
For the rapid detection of the total organic carbon(TOC)content and cation exchange capacity(CEC)in soil,visible/near infrared spectra(Vis/NIR)of 300 soil samples were analyzed.The algorithm of fast independent component analysis(FastleA)was used to decompose the data of Vis/NIR spectrum,and their independent components and the mixing matrix were obtained.Then,the calibration model with three-level artificial neural networks structure was built by using Back-Propagation (BP)algorithm.Genetic algorithm was used to revise the weights of neural networks to quicken the rate of convergence and overcome the problem of falling easily into local minimums,and finally the ICA-GA-BP model was built The models were used to estimate the content of TOC and CEC in soil samples both in calibration set and predicted set Correlation coefficient(R~2)of prediction and root mean square error of prediction(RMSEP)were used as the evaluation indexes.The results indicate that the R for the prediction of TOC content and CEC can both reach 0.98.These indicated that the results of analysis were satisfiable based on ICA method,and offer a new approach to the fast prediction of components' contents in soil.