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151.
Wavelength selection framework for classifying food and pharmaceutical samples into multiple classes
M. Anzanello F. Fogliatto M. C. A. Marcelo D. Pozebon M. F. Ferro 《Journal of Chemometrics》2016,30(6):346-353
Near infrared (NIR) spectroscopy is an efficient, low‐cost analytical technique widely applied to identify the origin of food and pharmaceutical products. NIR spectra‐based classification strategies typically use thousands of equally spaced wavelengths as input information, some of which may not carry relevant information for product classification. When that is the case, the performance of predictive and exploratory multivariate techniques may be undermined by such noisy information. In this paper, we propose an iterative framework for selecting subsets of NIR wavelengths aimed at classifying samples into categories. For that matter, we integrate Principal Components Analysis (PCA) and three classification techniques: k‐Nearest Neighbor (KNN), Probabilistic Neural Network (PNN) and Linear Discriminant Analysis (LDA). PCA is first applied to NIR data, and a wavelength importance index is derived based on the PCA loadings. Samples are then categorized using the wavelength with the highest index and the classification accuracy is calculated; next, the wavelength with the second highest index is inserted into the dataset and a new classification is performed. This forward‐based iterative procedure is carried out until all original wavelengths are inserted into the dataset used for classification. The subset of wavelengths leading to the maximum accuracy is chosen as the recommended subset. Our propositions performed remarkably well when applied to four datasets related to food and pharmaceutical products. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
152.
Russian Journal of Applied Chemistry - An increase in the production and consumption of polyurethane products used in heavy and light industry, in the construction industry, automotive, medicine,... 相似文献
153.
Kondrateva V. Yu. Martynenko E. A. Pimerzin A. A. Verevkin S. P. 《Russian Journal of Applied Chemistry》2022,95(1):126-134
Russian Journal of Applied Chemistry - Pt/Sup catalysts with SiO2, MCM-48, and Al2O3 supports (Sup) were prepared. The catalysts were studied by methods of low-temperature nitrogen adsorption,... 相似文献
154.
Markosyan A. I. Ayvazyan A. S. Gabrielyan S. H. Mamyan S. S. 《Russian Journal of Organic Chemistry》2022,58(2):200-208
Russian Journal of Organic Chemistry - Starting from 3-(2,2-dimethyltetrahydro-2H-pyran-4-yl)-2-thioxo-2,3-dihydro-1H-spiro(benzo[h]quinazoline-5,1'-cycloheptan)-4(6H)-one, a series of... 相似文献
155.
Russian Journal of Organic Chemistry - A new series of 4-(1H-imidazol-4-yl)-2-(substituted phenyl)-1,4-dihydrobenzo[4,5]imidazo[1,2-a]pyrimidines have been synthesized via a one-pot reaction... 相似文献
156.
Sarkate A. P. Sarode P. P. Bhandari S. V. Karnik K. S. Narula I. S. Kale B. D. Jambhorkar V. S. Rajhans A. P. 《Russian Journal of Organic Chemistry》2022,58(3):428-432
Russian Journal of Organic Chemistry - A new convenient method has been developed for the synthesis of quinazolinones from 2-phenyl-1H-indole and substituted amines under catalysis by... 相似文献
157.
Kustova T. P. Kochetova L. B. Khachatryan D. S. 《Russian Journal of Organic Chemistry》2022,58(4):512-517
Russian Journal of Organic Chemistry - The reactivities of the L-Tyr–L-Pro dipeptide and its analog with a hydroxymethyl group instead of carboxy group in the proline moiety were compared by... 相似文献
158.
Russian Journal of Organic Chemistry - A series of novel fused thiadiazine derivatives have been simply synthesized through the reaction of hydrazinecarbodithioic acid with various cyclic... 相似文献
159.
Brandaleze Elena Ávalos M. Benavidez Edgardo 《Journal of Thermal Analysis and Calorimetry》2022,147(1):219-228
Journal of Thermal Analysis and Calorimetry - Recent advances in the technology of black refractories for steel continuous casting promote the development of materials that operate at extreme... 相似文献