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Determination of Active Components in a Natural Herb with Near Infrared Spectroscopy Based on Artificial Neural Networks 被引量:7
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作者 LIUXue-song QUHai-bin CHENGYi-yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期36-43,共8页
The non-linear relationships between the contents of ginsenoside Rg 1, Rb 1, Rd and Panax notoginseng saponins(PNS) in Panax notoginseng root herb and the near infrared(NIR) diffuse reflectance spectra of the herb wer... The non-linear relationships between the contents of ginsenoside Rg 1, Rb 1, Rd and Panax notoginseng saponins(PNS) in Panax notoginseng root herb and the near infrared(NIR) diffuse reflectance spectra of the herb were established by means of artificial neural networks(ANNs). Four three-layered perception feed-forward networks were trained with an error back-propagation algorithm. The significant principal components of the NIR spectral data matrix were utilized as the input of the networks. The networks architecture and parameters were selected so as to offer less prediction errors. Relative prediction errors for Rg 1, Rb 1, Rd and PNS obtained with the optimum ANN models were 8.99%, 6.54%, 8.29%, and 5.17%, respectively, which were superior to those obtained with PLSR methods. It is verified that ANN is a suitable approach to model this complex non-linearity. The developed method is fast, non-destructive and accurate and it provides a new efficient approach for determining the active components in the complex system of natural herbs. 展开更多
关键词 Near infrared diffuse reflectance spectroscopy artificial neural network PLSR Non-linearity Analysis of natural herb Panax notoginseng
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Prediction Modeling and Mapping of Soil Carbon Content Using Artificial Neural Network, Hyperspectral Satellite Data and Field Spectroscopy 被引量:4
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作者 Sudheer Kumar Tiwari Sudip Kumar Saha Suresh Kumar 《Advances in Remote Sensing》 2015年第1期63-72,共10页
Soil organic carbon (SOC) is an important and reliable indicator of soil quality. In this study, soil spectra were characterized and analysed to predict the spatial soil organic carbon (SOC) content using multivariate... Soil organic carbon (SOC) is an important and reliable indicator of soil quality. In this study, soil spectra were characterized and analysed to predict the spatial soil organic carbon (SOC) content using multivariate predictive modeling technique-artificial neural network (ANN). EO1-Hyperion (400 - 2500 nm) hyperspectral image, field and laboratory scale data sets (350 - 2500 nm) were generated which consisted of laboratory estimated SOC content of collected soil samples (dependent variable) and their corresponding reflectance data of SOC sensitive spectral bands (predictive variables). For each data set, ANN predictive models were developed and all three datasets (image-scale, field-scale and lab-scale) revealed significant network performances for training, testing and validation indicating a good network generalization for SOC content. ANN based analysis showed high prediction of SOC content at image (R2 = 0.93, and RPD = 3.19), field (R2 = 0.92 and RPD = 3.17), and lab scale (R2 = 0.95 and RPD = 3.16). Validation results of ANN indicated that predictive models performed well (R2 = 0.90) with RMSE 0.070. The result showed that ANN methods had a great potential for estimating and mapping spatial SOC content. The study concluded that ANN model was potential tools in predicting SOC distribution in agricultural field using hyper-spectral remote sensing data at image-scale, field-scale and lab-scale. 展开更多
关键词 Soil Carbon artificial neural network HYPERSPECTRAL IMAGINE spectroscopy HYPERION
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Artificial neural network approach to assess selective flocculation on hematite and kaolinite 被引量:2
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作者 Lopamudra Panda P.K.Banerjee +2 位作者 Surendra Kumar Biswal R.Venugopal N.R.Mandre 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第7期637-646,共10页
Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alt... Because of the current depletion of high grade reserves, beneficiation of low grade ore, tailings produced and tailings stored in tailing ponds is needed to fulfill the market demand. Selective flocculation is one alternative process that could be used for the beneficiation of ultra-fine material. This process has not been extensively used commercially because of its complex dependency on process parameters. In this paper, a selective flocculation process, using synthetic mixtures of hematite and kaolinite in different ratios, was attempted, and the ad-sorption mechanism was investigated by Fourier transform infrared (FTIR) spectroscopy. A three-layer artificial neural network (ANN) model (4?4?3) was used to predict the separation performance of the process in terms of grade, Fe recovery, and separation efficiency. The model values were in good agreement with experimental values. 展开更多
关键词 HEMATITE KAOLINITE FLOCCULATION artificial neural networks back propagation algorithm Fourier transform infrared spectroscopy separation efficiency
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Application of Near Infrared Diffuse Reflectance Spectroscopy with Radial Basis Function Neural Network to Determination of Rifampincin Isoniazid and Pyrazinamide Tablets 被引量:3
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作者 DU Lin-na WU Li-hang +5 位作者 LU Jia-hui GUO Wei-liang MENG Qing-fan JIANG Chao-jun SHEN Si-le TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第5期518-523,共6页
Partial least squares(PLS),back-propagation neural network(BPNN)and radial basis function neural network(RBFNN)were respectively used for estalishing quantative analysis models with near infrared(NIR)diffuse r... Partial least squares(PLS),back-propagation neural network(BPNN)and radial basis function neural network(RBFNN)were respectively used for estalishing quantative analysis models with near infrared(NIR)diffuse reflectance spectra for determining the contents of rifampincin(RMP),isoniazid(INH)and pyrazinamide(PZA)in rifampicin isoniazid and pyrazinamide tablets.Savitzky-Golay smoothing,first derivative,second derivative,fast Fourier transform(FFT)and standard normal variate(SNV)transformation methods were applied to pretreating raw NIR diffuse reflectance spectra.The raw and pretreated spectra were divided into several regions,depending on the average spectrum and RSD spectrum.Principal component analysis(PCA)method was used for analyzing the raw and pretreated spectra in different regions in order to reduce the dimensions of input data.The optimum spectral regions and the models' parameters were chosen by comparing the root mean square error of cross-validation(RMSECV)values which were obtained by leave-one-out cross-validation method.The RMSECV values of the RBFNN models for determining the contents of RMP,INH and PZA were 0.00288,0.00226 and 0.00341,respectively.Using these models for predicting the contents of INH,RMP and PZA in prediction set,the RMSEP values were 0.00266,0.00227 and 0.00411,respectively.These results are better than those obtained from PLS models and BPNN models.With additional advantages of fast calculation speed and less dependence on the initial conditions,RBFNN is a suitable tool to model complex systems. 展开更多
关键词 Rifampicin isoniazid and pyrazinamide tablets nir diffuse reflectance spectroscopy Partial least square Back-propagation neural network Radial basis function neural network
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Application of principal component-radial basis function neural networks (PC-RBFNN) for the detection of water-adulterated bayberry juice by near-infrared spectroscopy 被引量:5
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作者 Li-juan XIE Xing-qian YE Dong-hong LIU Yi-bin YING 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第12期982-989,共8页
Near-infrared (NIR) spectroscopy combined with chemometrics techniques was used to classify the pure bayberry juice and the one adulterated with 10% (w/w) and 20% (w/w) water. Principal component analysis (PCA) was ap... Near-infrared (NIR) spectroscopy combined with chemometrics techniques was used to classify the pure bayberry juice and the one adulterated with 10% (w/w) and 20% (w/w) water. Principal component analysis (PCA) was applied to reduce the dimensions of spectral data, give information regarding a potential capability of separation of objects, and provide principal component (PC) scores for radial basis function neural networks (RBFNN). RBFNN was used to detect bayberry juice adulterant. Multiplicative scatter correction (MSC) and standard normal variate (SNV) transformation were used to preprocess spectra. The results demonstrate that PC-RBFNN with optimum parameters can separate pure bayberry juice samples from water-adulterated bayberry at a recognition rate of 97.62%, but cannot clearly detect water levels in the adulterated bayberry juice. We conclude that NIR technology can be successfully applied to detect water-adulterated bayberry juice. 展开更多
关键词 Near-infrared nir spectroscopy Principal component-radial basis function neural networks (PC-RBFNN) Bayberry juice ADULTERATION Chemometrics technique
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Quantitative Near-infrared Spectroscopic Analysis of Trimethoprim by Artificial Neural Networks Combined with Modified Genetic Algorithm 被引量:1
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作者 SHAN Hongyan FEI Yanqun +2 位作者 HUAN Yanfu FENG Guodong FEI Qiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2014年第4期582-586,共5页
A novel method for rapid,accurate and nondestructive determination of trimethoprim in complex matrix was presented.Near-infrared spectroscopy coupled with multivariate calibration(partial least-squares and artificial... A novel method for rapid,accurate and nondestructive determination of trimethoprim in complex matrix was presented.Near-infrared spectroscopy coupled with multivariate calibration(partial least-squares and artificial neural networks) was applied in the experiment.The variable selection process based on a modified genetic algorithm with fixed number of selected variables was proceeded,which can reduce the training time and enhance the predictive ability when coupled with artificial neural network model. 展开更多
关键词 artificial neural network Genetic algorithm Near-infrared spectroscopy TRIMETHOPRIM
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Optofluidic identification of single microorganisms using fiber-optical-tweezer-based Raman spectroscopy with artificial neural network 被引量:1
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作者 Chenghong Lin Xiaofeng Li +7 位作者 Tianli Wu Jiaqi Xu Zhiyong Gong Taiheng Chen Baojun Li Yuchao Li Jinghui Guo Yao Zhang 《BMEMat(BioMedical Engineering Materials)》 2023年第1期70-79,共10页
Rapid and accurate detection of microorganisms is critical to clinical diagnosis.As Raman spectroscopy promises label-free and culture-free detection of biomedical objects,it holds the potential to rapidly identify mi... Rapid and accurate detection of microorganisms is critical to clinical diagnosis.As Raman spectroscopy promises label-free and culture-free detection of biomedical objects,it holds the potential to rapidly identify microorganisms in a single step.To stabilize the microorganism for spectrum collection and to increase the accuracy of real-time identification,we propose an optofluidic method for single microorganism detection in microfluidics using optical-tweezing-based Raman spectroscopy with artificial neural network.A fiber optical tweezer was incorporated into a microfluidic channel to generate op-tical forces that trap different species of microorganisms at the tip of the tweezer and their Raman spectra were simultaneously collected.An artificial neural network was designed and employed to classify the Raman spectra of the microorganisms,and the identification accuracy reached 94.93%.This study provides a promising strategy for rapid and accurate diagnosis of mi-crobial infection on a lab-on-a-chip platform. 展开更多
关键词 artificial neural network fiber optical tweezers MICROORGANISMS Raman spectroscopy single-cell identification
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苹果品种及损伤苹果的FT-NIR鉴别研究 被引量:11
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作者 李光辉 任亚梅 +4 位作者 任小林 赵玉 李帅 苏晋文 刘朵 《食品科学》 EI CAS CSCD 北大核心 2012年第16期251-256,共6页
用傅里叶近红外光谱技术(FT-NIR)对不同品种的苹果以及损伤嘎啦和完好嘎啦进行快速、无损检测,比较不同判别方法对所建立的区分苹果品种及苹果损伤模型的影响。结果表明:损伤嘎啦和完好嘎啦的近红外图谱经小波分析预处理后,用12000~400... 用傅里叶近红外光谱技术(FT-NIR)对不同品种的苹果以及损伤嘎啦和完好嘎啦进行快速、无损检测,比较不同判别方法对所建立的区分苹果品种及苹果损伤模型的影响。结果表明:损伤嘎啦和完好嘎啦的近红外图谱经小波分析预处理后,用12000~4000cm-1波数范围的前5个主成分分别结合多层感知神经网络、径向基神经网络、Fisher判别3种方法所建立的判别模型对未知样本的正确判别率分别为97.8%、87.2%和84.8%,基于权重法用多元线性回归(MLR)所选择的特征波长所建立的Fisher判别模型对未知样本的正确判别率为89.1%;用偏最小二乘判别(PLS-DA)所建立的判别模型对未知样本的正确判别率为100%,由于PLS-DA模型对训练集和验证集的正确判别率均为100%,因此PLS-DA模型优于其他模型。不同品种苹果的光谱经平滑预处理后,用全波数范围12000~4000cm-1的前6个主成分所建立的判别模型优于经验波数范围8000~4500cm-1所建立的判别模型,其较优模型对建模集和验证集的正确判别率分别为90.9%和92.1%。近红外光谱技术结合化学计量学可以快速、无损鉴别苹果是否有损伤以及不同品种的苹果。 展开更多
关键词 苹果 近红外技术 神经网络 偏最小二乘判别 FISHER判别
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基于FT-NIR的微生物快速鉴定方法研究 被引量:14
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作者 岳田利 王军 +1 位作者 袁亚宏 高振鹏 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2010年第11期2945-2949,共5页
微生物细胞的傅里叶变换近红外光谱(Fourier transform near infrared spectroscopy,FT-NIR)反映了细胞成分的分子振动信息,具有的高度特异性,为寻求一种基于FT-NIR的微生物快速鉴定方法提供了可能。文章通过采集1株酵母和5株细菌标准... 微生物细胞的傅里叶变换近红外光谱(Fourier transform near infrared spectroscopy,FT-NIR)反映了细胞成分的分子振动信息,具有的高度特异性,为寻求一种基于FT-NIR的微生物快速鉴定方法提供了可能。文章通过采集1株酵母和5株细菌标准菌株的近红外漫反射光谱,采用主成分分析法对光谱数据进行了分析,构建了基于FT-NIR的微生物快速鉴定模型。分析结果表明:①光谱鉴别指数Dy1y2值范围为1.61±1.05~10.97±6.65,重现性良好;②建立的基于线性判别分析模型的鉴定准确率为100%,基于人工神经网络模型的预测结果平均相对误差为5.75%,预测准确率高。研究结果证实该方法可以实现基于FT-NIR结合多元数学统计方法的微生物快速鉴定,并具有广阔的产业应用前景。 展开更多
关键词 傅里叶变换近红外光谱 微生物 快速鉴定 线性判别 人工神经网络
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利用神经网络提高偏最小二乘法的NIR多组分分析精度 被引量:17
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作者 白英奎 孟宪江 +1 位作者 丁东 申铉国 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2005年第3期381-383,共3页
提出了一种神经网络 (ANN)和偏最小二乘法 (PLS)结合的新的近红外 (NIR)多组分分析法。该方法首先把训练样本中待测组分涵盖的浓度区间分成若干个子区间 ,利用各个子区间的训练样本分别建立PLS校正模型 ,然后利用ANN对未知样本进行分类 ... 提出了一种神经网络 (ANN)和偏最小二乘法 (PLS)结合的新的近红外 (NIR)多组分分析法。该方法首先把训练样本中待测组分涵盖的浓度区间分成若干个子区间 ,利用各个子区间的训练样本分别建立PLS校正模型 ,然后利用ANN对未知样本进行分类 ,判断其所属的浓度子区间 ,应用对应子区间上的校正模型计算预测样本的组分浓度。和传统的PLS比较 ,此方法改善了模型的适应性 ,显著地提高了预测精度。实验及数据处理结果证明了本方法的有效性。 展开更多
关键词 子区间 多组分分析 校正模型 偏最小二乘法 证明 样本 预测精度 PLS nir 浓度
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基于舌诊NIR反射光谱血清总蛋白含量的无创测量 被引量:8
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作者 林凌 李哲 +4 位作者 李晓霞 李永成 李刚 张宝菊 宋维 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2012年第8期2110-2116,共7页
采用舌诊近红外反射光谱对人体血清总蛋白(TP)含量进行无创检测。采集58例舌尖反射光谱进行反射率归一化并记录相对应的血清总蛋白生化分析值,将样本分为训练集和预测集,运用主成分分析结合BP神经网络法和偏最小二乘算法分别建立预测模... 采用舌诊近红外反射光谱对人体血清总蛋白(TP)含量进行无创检测。采集58例舌尖反射光谱进行反射率归一化并记录相对应的血清总蛋白生化分析值,将样本分为训练集和预测集,运用主成分分析结合BP神经网络法和偏最小二乘算法分别建立预测模型。主成分分析结合BP神经网络模型对预测集进行预测,平均相对误差为7.35%,均方根误差为3.069 1g.L-1,相关系数为0.902 1。偏最小二乘模型对预测集进行预测,平均相对误差为4.77%,均方根误差为0.130 1g.L-1,相关系数为0.971 8。实验结果证实了舌诊近红外反射光谱可以较为准确地用于总蛋白含量的无创检测。 展开更多
关键词 近红外反射光谱 舌诊 血清总蛋白(TP) BP神经网络 偏最小二乘(PLS)
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基于Vis-NIR光谱的土壤质地BP神经网络预测 被引量:7
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作者 王德彩 张俊辉 《天津农业科学》 CAS 2015年第8期6-9,共4页
为快速、准确地获取土壤质地信息,提出了应用Vis-NIR光谱结合BP神经网络的建模方法。以河南封丘县的86个土壤样本为研究对象,以原始光谱和微分光谱主成分为输入变量,建立土壤粘粒和砂粒的BP神经网络预测模型,并将其预测结果与多元线性... 为快速、准确地获取土壤质地信息,提出了应用Vis-NIR光谱结合BP神经网络的建模方法。以河南封丘县的86个土壤样本为研究对象,以原始光谱和微分光谱主成分为输入变量,建立土壤粘粒和砂粒的BP神经网络预测模型,并将其预测结果与多元线性逐步回归模型进行比较。结果表明:基于原始光谱主成分的BP人工神经网络预测结果最好,优于多元逐步回归模型,预测粘粒和砂粒的RMSE分别为1.62和6.52。BP神经网络所建模型训练时间短、准确度也较高,能实现对土壤质地的高效预测。 展开更多
关键词 Vis-nir光谱 BP神经网络 主成分分析 土壤质地
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LS-SVM和BP-ANN在草莓糖度NIR检测中的应用 被引量:3
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作者 牛晓颖 赵志磊 张晓瑜 《农机化研究》 北大核心 2013年第5期204-207,共4页
为了提高草莓糖度近红外光谱定量模型的性能,采用偏最小二乘法提取的潜在变量作为最小二乘—支持向量机和反向传播人工神经网络的输入变量,建立了草莓糖度的近红外定量模型,并与偏最小二乘模型结果进行了比较,建模所使用的光谱范围为6 ... 为了提高草莓糖度近红外光谱定量模型的性能,采用偏最小二乘法提取的潜在变量作为最小二乘—支持向量机和反向传播人工神经网络的输入变量,建立了草莓糖度的近红外定量模型,并与偏最小二乘模型结果进行了比较,建模所使用的光谱范围为6 000~9 000 cm-1。结果表明,所建立的最小二乘—支持向量机和反向传播人工神经网络定量模型的校正性能、预测性能和稳定性均优于偏最小二乘定量模型,最优模型为前10个潜在变量得分作为输入变量的最小二乘—支持向量机模型,其校正和预测相关系数分别为0.957和0.951,校正和预测均方根误差分别为0.279%和0.272%,剩余预测偏差为3.23,与以往研究文献相比,获得了较为理想的预测精度和稳定性能。 展开更多
关键词 草莓 糖度 近红外 最小二乘支持向量机 反向传播人工神经网络 潜在变量
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人工神经网络NIR定量分析方法及其软件实现 被引量:5
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作者 祝诗平 《农业机械学报》 EI CAS CSCD 北大核心 2007年第1期108-111,共4页
在VisualC++环境中采用面向对象技术,开发了PCA-MBP-NIR定量分析模型软件。通过40份小麦样品的原始光谱、加噪光谱(信噪比为14dB)与含水率所建立的PLS-NIR与PCA-MBP-NIR模型,对10份未知小麦样品的原始光谱、加噪光谱分别进行含水率的PLS... 在VisualC++环境中采用面向对象技术,开发了PCA-MBP-NIR定量分析模型软件。通过40份小麦样品的原始光谱、加噪光谱(信噪比为14dB)与含水率所建立的PLS-NIR与PCA-MBP-NIR模型,对10份未知小麦样品的原始光谱、加噪光谱分别进行含水率的PLS-NIR与PCA-MBP-NIR预测分析。分析表明,对于含噪声的光谱,与PLS建模相比,使用PCA-MBP-NIR对未知样品预测结果具有更高的相关系数,更低的预测误差标准差。 展开更多
关键词 农产品 品质检测 近红外光谱分析 主成分分析 人工神经网络
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基于NIR的模式识别技术在地理标志产品响水大米鉴别中的应用 被引量:5
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作者 谌蓓 夏立娅 +2 位作者 窦玉蕾 马泽洋 熊娜 《河北大学学报(自然科学版)》 CAS 北大核心 2013年第5期484-488,共5页
分别利用多元线性回归判别分析和BP人工神经网络分析建立了近红外光谱(NIR)快速鉴别地理标志产品响水大米的新方法.大米的近红外光谱数据经过一阶导数和平滑处理后,利用主成分分析对数据进行了降维处理,并确定了相关性最大的特征... 分别利用多元线性回归判别分析和BP人工神经网络分析建立了近红外光谱(NIR)快速鉴别地理标志产品响水大米的新方法.大米的近红外光谱数据经过一阶导数和平滑处理后,利用主成分分析对数据进行了降维处理,并确定了相关性最大的特征波段(7700~6700cm-1与5700~4300cm-1).利用特征波段的主成分数据建立了多元线性回归判别分析和BP人工神经网络鉴别模型.2种模型对于地理标志产品响水大米的鉴别正确率均为100%,适用于地理标志产品的快速无损鉴别. 展开更多
关键词 多元线性回归分析 BP人工神经网络 地理标志产品 响水大米 近红外
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基于集群算法优化BP神经网络的NIRS树种识别研究 被引量:4
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作者 明曼曼 陈芳 +3 位作者 孙恺琦 顾崎岩 吴思齐 王学顺 《西部林业科学》 CAS 北大核心 2020年第5期124-128,共5页
为探究基于近红外光谱分析技术的木材树种准确、快速识别新方法,并研究光谱波段范围对识别的影响,以大叶桉、杉木、落叶松、马尾松、樟子松5种木材样品为研究对象,针对3种光谱波段范围,分别建立未优化的BP神经网络模型(BP-ANN)、粒子群... 为探究基于近红外光谱分析技术的木材树种准确、快速识别新方法,并研究光谱波段范围对识别的影响,以大叶桉、杉木、落叶松、马尾松、樟子松5种木材样品为研究对象,针对3种光谱波段范围,分别建立未优化的BP神经网络模型(BP-ANN)、粒子群算法优化BP神经网络模型(PSO-BP)和人工蜂群算法优化BP神经网络模型(ABC-BP),对比模型识别准确率和运行时间。研究结果显示,波段越长,模型的识别准确率越高;PSO-BP与ABC-BP模型的识别准确率均高于BP-ANN,其中ABC-BP模型的识别效果最好,可达到95.333%;ABC算法较于PSO算法优化BP神经网络模型用于木材近红外光谱树种识别时间更短。基于集群算法优化BP神经网络模型能有效应用于树种识别研究,具有一定应用前景。 展开更多
关键词 近红外光谱技术 木材树种识别 BP神经网络 人工蜂群算法 粒子群算法
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Quantitative Analysis of Berberine in Processed Coptis by Near-Infrared Diffuse Reflectance Spectroscopy 被引量:4
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作者 ZHANG Yong XIE Yun-fei +3 位作者 SONG Feng-rui LIU Zhi-qiang CONG Qian ZHAO Bing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期717-721,共5页
The near-infrared(NIR) diffuse reflectance spectroscopy was used to study the content of Berberine in the processed Coptis. The allocated proportions of Coptis to ginger, yellow liquor or Evodia rutaecarpa changed a... The near-infrared(NIR) diffuse reflectance spectroscopy was used to study the content of Berberine in the processed Coptis. The allocated proportions of Coptis to ginger, yellow liquor or Evodia rutaecarpa changed according to the results of orthogonal design as well as the temperature. For as withdrawing the full and effective information from the spectral data as possible, the spectral data was preprocessed through first derivative and multiplicative scatter correetion(MSC) according to the optimization results of different preprocessing methods. Firstly, the model was established by partial least squares(PLS); the coefficient of determination(R2) of the prediction was 0.839, the root mean squared error of prediction(RMSEP) was 0.1422, and the mean relative error(RME) was 0.0276. Secondly, for reducing the dimension and removing noise, the spectral variables were highly effectively compressed via the wavelet transformation(WT) technology and the Haar wavelet was selected to decompose the spectral signals. After the wavelet coefficients from WT were input into the artificial neural network(ANN) instead of the spectra signal, the quantitative analysis model of Berberine in processed Coptis was established. The R^2 of the model was 0.9153, the RMSEP was 0.0444, and the RME was 0.0091. The values of appraisal index, namely R^2, RMSECV, and RME, indicate that the generalization ability and prediction precision of ANN are superior to those of PLS. The overall results show that NIR spectroscopy combined with ANN can be efficiently utilized for the rapid and accurate analysis of routine chemical compositions in Coptis. Accordingly, the result can provide technical support for the further analysis of Berberine and other components in processed Coptis. Simultaneously, the research can also offer the foundation of quantitative analysis of other NIR application. 展开更多
关键词 Near-infrared(nir spectroscopy Partial least squares artificial neural network Wavelet transformation BERBERINE
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Selection of Spectral Data for Classification of Steels Using Laser-Induced Breakdown Spectroscopy 被引量:2
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作者 孔海洋 孙兰香 +2 位作者 胡静涛 辛勇 丛智博 《Plasma Science and Technology》 SCIE EI CAS CSCD 2015年第11期964-970,共7页
Principal component analysis (PCA) combined with artificial neural networks was used to classify the spectra of 27 steel samples acquired using laser-induced breakdown spectroscopy. Three methods of spectral data se... Principal component analysis (PCA) combined with artificial neural networks was used to classify the spectra of 27 steel samples acquired using laser-induced breakdown spectroscopy. Three methods of spectral data selection, selecting all the peak lines of the spectra, selecting intensive spectral partitions and the whole spectra, were utilized to compare the infiuence of different inputs of PCA on the classification of steels. Three intensive partitions were selected based on experience and prior knowledge to compare the classification, as the partitions can obtain the best results compared to all peak lines and the whole spectra. We also used two test data sets, mean spectra after being averaged and raw spectra without any pretreatment, to verify the results of the classification. The results of this comprehensive comparison show that a back propagation network trained using the principal components of appropriate, carefully selecred spectral partitions can obtain the best results accuracy can be achieved using the intensive spectral A perfect result with 100% classification partitions ranging of 357-367 nm. 展开更多
关键词 laser-induced breakdown spectroscopy classification of steel samples principal component analysis artificial neural networks selection of spectral data
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Geographic Classification of Chinese Grape Wines by Near-Infrared Reflectance Spectroscopy 被引量:1
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作者 赵芳 赵育 +1 位作者 毛文华 战吉宬 《Journal of Donghua University(English Edition)》 EI CAS 2012年第1期40-45,共6页
Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mod... Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mode in the wavelength range of 800-2500 nm. Wines (n=90) were randomly split into two sets, calibration set (n=54) and validation set (n=36). Discriminant analysis models were developed using BP neural network and discriminant partial least-squares discriminant analysis (PLS-DA). The prediction performance of calibration models in different wavelength range was also investigated. BP neural network models and PLS-DA models correctly classified 100% of the wines in calibration set. When used to predict wines in validation set, BP neural network models correctly classified 100%, 81.8%, and 90.9% of the wines from Changli, Huailai, and Yantai respectively, and PLS-DA models correctly classified 100% of all samples. The results demonstrated that NIRS could be used to discriminate Chinese grape wines as a rapid and reliable method. 展开更多
关键词 near-infrared reflectance spectroscopy (nirS) Chinese grape wines discriminant analysis models BP neural network PLS-DA
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Artifcial eur ral networks based estimation of optical parameters by diffuse reflectance imaging under in vitro conditions 被引量:1
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作者 Mahmut Ozan Gokkan Mehmet Engin 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2017年第1期1-10,共10页
Optical parameters(properties)of tissue-mimicking phantoms are determined through nonin-vasive optical imaging.Objective of this study is to decompose obtained difuse reflectance into these optical properties such as ... Optical parameters(properties)of tissue-mimicking phantoms are determined through nonin-vasive optical imaging.Objective of this study is to decompose obtained difuse reflectance into these optical properties such as absorption and scattering coefficients.To do so,transmission spectroscopy is firstly used to measure the coefficients via an experimental setup.Next,the optical properties of each characterized phantom are input for Monte Carlo(MC)simulations to get diffuse reflectance.Also,a surface image for each single phantom with its known optical properties is obliquely captured due to reflectance-based geometrical setup using CMOS camera that is positioned at 5°angle to the phantoms.For the illumination of light,a laser light source at 633 nm wavelength is preferred,because optical properties of different components in a biological tissue on that wavelength are nonoverlapped.During in vitro measurements,we prepared 30 different mixture samples adding clinoleic intravenous lipid emulsion(CILE)and evans blue(EB)dye into a distilled water.Finally,all obtained difuse reflectance values are used to estimate the optical coefficients by artificial neural networks(ANNs)in inverse modeling.For a biological tissue it is found that the simulated and measured values in our results are in good agreement. 展开更多
关键词 Optical properties difuse reflectance spectroscopy Monte Carlo simulation artificial neural networks.
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