Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 5 de 5
Filter
Add more filters










Database
Publication year range
1.
Spectrochim Acta A Mol Biomol Spectrosc ; 299: 122828, 2023 Oct 15.
Article in English | MEDLINE | ID: mdl-37192577

ABSTRACT

Compared with the complexity of chemical methods, near-infrared spectroscopy (NIRS) is widely used in the detection of protein content because of its advantages of being fast and non-destructive. Aiming to tackle the problem that the raw near-infrared spectroscopy contains many redundant wavelengths, which affects the accuracy of quantitative prediction and requires expertise to process, we propose an end-to-end network: Band Reweighted Network (BR-Net) that automates wavelength reweighted and quantitative prediction of protein content in rapeseed. Unlike extracting part of wavelengths by the traditional wavelength selection methods, BR-Net retains all spectral wavelengths and assigns different weights to the wavelengths to express the correlation with the corresponding concentration, which enables wavelength selection without ignoring the information contained in the less relevant wavelengths. We compare BR-Net with traditional selection methods such as SPA, LARS, CARS, and UVE to verify its efficiency and robustness, finding that the R2 of the training set and test set are 0.9797 and 0.9215, the RMSEC and RMSEP are 0.4053 and 0.8501, respectively, and the RPD is 3.5686, which prove BR-Net outperforms all the traditional methods. The network described here is universally applicable to a variety of NIR quantitative analyses.


Subject(s)
Brassica napus , Least-Squares Analysis , Algorithms , Spectroscopy, Near-Infrared/methods , Proteins
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120757, 2022 Apr 05.
Article in English | MEDLINE | ID: mdl-34973617

ABSTRACT

The excessive content of additives in food is a radical problem that affects human health. However, traditional chemical methods are limited by a long cycle, low accuracy, and strong destructiveness, so a fast and accurate alternative is urgently needed. This paper proposes a prediction model introducing near-infrared spectroscopy and deep learning to perform fast and accurate non-destructive detection of artificial bright blue pigment in cream. The model results show that R2 is 0.9638, RMSEP is 0.0157, and RPD is 4.4022. In the preprocessing part, this paper compares the traditional preprocessing methods (SNV, MSC, SG) horizontally and innovatively proposes the use of autoencoders to mitigate the dimensionality of data, which has immensely improved the follow-up prediction effect. In addition, it tries to perform regression prediction on spectral data and establish a fully connected convolutional neural network model through deep learning, whose result indicators prove better than those of traditional methods such as PLSR and MLR. When constructing the deep learning model, this paper applies knowledge evolution to compress the model to achieve a lower calculation cost and higher accuracy. Compared with the traditional methods, the model proposed in this paper has greater accuracy and higher speed with samples undamaged, which is worth popularizing.


Subject(s)
Deep Learning , Spectroscopy, Near-Infrared , Food , Humans , Least-Squares Analysis , Neural Networks, Computer
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 242: 118718, 2020 Dec 05.
Article in English | MEDLINE | ID: mdl-32750652

ABSTRACT

Based on near-infrared spectrum and interval random forest, a fast quantitative analysis method for the content of sunset yellow content was established. The spectra of 132 cream pigment samples were obtained by FT-NIR spectrometer, and various preprocessing methods such as standard normal variable (SNV), wavelet transform (WT), and SG (Savitzky-Golay) were used to smooth and denoise the original spectrum. In this paper, WT and first-order differentiation were used as pretreatment and the Kennard-Stone algorithm was used to divide the data set. Finally interval partial least squares, partial least squares, interval random forest and random forest were used to construct an optimal quantitative analysis model. The experimental results show that the interval random forest can find the best sub-interval to achieve the prediction ability of the model. The R2 (the coefficient of determination) and RMSEP (root mean square error of the prediction) of the prediction set are 0.8965 and 0.2454, respectively. The research results show that near-infrared spectroscopy combined with interval random forest algorithm is a fast and non-destructive method to detect the content of sunset yellow in cream.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 227: 117551, 2020 Feb 15.
Article in English | MEDLINE | ID: mdl-31677907

ABSTRACT

Artificial pigment is a common food additive in cream products. If added in excess, it will do harm to human body. At present, there is no research on the detection of cream pigment by Near Infrared (NIR) spectroscopy. In this paper, a method based on random forest was applied to determine the indigotine in cream. Weighting in the experiments was accomplished using analytical balances with precision as low as 0.0001 g. The NIR spectra data of cream with different concentration of indigotine were recorded. The original spectra was pretreated by SG smoothing, mean centering and second derivative. Random forest was applied to establish a quantitative analysis model for cream pigment content, and multiple evaluation criteria were selected to comprehensively evaluate the model. The R2 was 0.9402, RMSEP was 0.2509 and RPD was 4.0893. Consequently, NIR spectroscopy, combined with data pretreatments and random forest model, was confirmed to be an interesting tool for non-destructive evaluation of pigment content in cream.


Subject(s)
Food Analysis/methods , Food Coloring Agents/analysis , Indigo Carmine/analysis , Spectroscopy, Near-Infrared/methods , Algorithms , Least-Squares Analysis , Machine Learning
5.
Sheng Wu Gong Cheng Xue Bao ; 35(7): 1151-1161, 2019 Jul 25.
Article in Chinese | MEDLINE | ID: mdl-31328472

ABSTRACT

Microbial cells cultivation is not only the origin, but also the foundation of microbiology. Researches in microbiology can only be carried out when the microbial cells can be cultured. However, conventional microbial cell cultivation is not only time consuming and labour intensive, but human error is also inevitable. Recent years, automated, modularised microbial cells micro-cultivation systems with small volume, good controllability, and equipped with real-time monitoring system have attracted great attention in microbiology. This review presents the state-of-the-art micro-cultivation systems which are implemented in microbial cells cultivation. The key development, applications of various system classified based on their construction, and the prospects of micro-cultivation system are discussed and insights into them are also provided.


Subject(s)
Bioreactors , Humans
SELECTION OF CITATIONS
SEARCH DETAIL
...