• Korean Journal of Food Science and Technology
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• v.26 no.6
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• pp.718-725
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• 1994

The applicability of near infrared reflectance spectroscopy (NIRS) to determine moisture, protein, fat and amylose content of domestic rice was studied. The standard error of prediction (SEP) of moisture, protein, fat and amylose in polished rice was 0.014, 0.196, 0.098 and 1.427%, and those SEP of brown rice was 0.12, 1.226, 0.153 and 1.923%, respectively. It is concluded that the NIRS method allowed to detect the content of moisture and protein in rice samples with fair precision comparing conventional analysis, but the accuracy for determining amylose and fat was not acceptable.

• Korean Journal of Food Science and Technology
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• v.28 no.5
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• pp.916-921
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• 1996

This study was conducted to measure fat contents of potatochips by near infrared spectroscopy (NIRS). Both potatochip powder and potatochips were used to find correlations between the absorbance at certain wavelengths find the fat contents. Based on the correlation analysis, linear regression models predicting the fat contents were developed to predict the fat contents. Artificial neural network (ANN) models were also developed. Predicted values were compared to the measured ones. The regression and the ANN model predicting the fat contents of potatochip powder had determination coefficients of 0.93 and 0.92, and standard errors of prediction (SEP) of 1.29% and 1.17%, respectively. The correlation analysis of potatochips showed that the determination coefficients were low. Therefore, the fat contents of not potatochips but potatochip powder could be measured by NIRS.

• Analytical Science and Technology
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• v.15 no.3
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• pp.243-247
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• 2002

A rapid and simple determination of diazepam in intact diazepam tablets has been investigated using the near infrared spectroscopy(NIRS) combined with partial least squares regession. The separate calibration curves of 2 mg and 5 mg diazepam tablets were studied, as well as the linearity, concentration range and reproducibility of those calibration curves were evaluated. The correlation coefficients of calibration curves of 2 mg and 5 mg diazepam tablets are 0.9416 and 0.9159, respectively and the standard errors of calibration curves(SEC) are 0.018% and 0.032%, respectively.

• Journal of Animal Environmental Science
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• v.20 no.4
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• pp.183-188
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• 2014

Near-infrared reflectance spectroscopy (NIRS) was used to study the potential of adulteration of imported forage. Hay samples were prepared two set ; calibration set and validation one. The former were mixed 12 sets from 100% to 50% with Yangcho (Chinese leymus, leymus chinensis Trin.) and the latter were adulterated with 6 set of 8% to 38% in 5% interval. Mixed materials with Yangcho were rice straw, reed and alfalfa. Stand error of prediction (SEP) in calibration equation for alfalfa, reed and rice straw were 0.97, 0.97 and 0.99 also 0.54, 0.86 and 1.26%. Multiple correlation coefficient ($R^2$) for alfalfa, reed and rice straw were 0.99, 0.97 and 0.99. SEP in the same samples were 1.88, 2.15 and 1.49, respectively.

• Polymer(Korea)
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• v.26 no.1
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• pp.80-87
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• 2002

A comparative study using electron-beam(EB) and thermal curing techniques was carried out to determine the effect of cure behavior and thermal stability of epoxy resins. In this work, benzylquinoxalinium hexafluoroantimonate(BQH) was used as a latent cationic catalyst for an epoxy resin. According to the thermogravimetric analysis(TGA), the decomposed activation energy based on Coats-Redfern method was higher in the case of thermal curing technique. This could be interpreted in terms of slow thermal diffusion rate resulted from high crosslink density of the thermally cured epoxy resin. However, the increase of hydroxyl group in the epoxy resin cured by EB technique was observed in near-infrared spectroscopy(NIRS) measurements, resulting in improving the stable short aromatic chain structure, integral procedural decomposition temperature, and finally ductile properties for high impact strengths.

• Journal of Korea Multimedia Society
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• v.24 no.2
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• pp.295-304
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• 2021

Learning assistance system that continuously measures user's concentration will be helpful to grasp the concentration pattern and adjust the learning method accordingly to improve the learning efficiency. Although a lot of various learning aids have been proposed, there have been few studies on the concentration monitoring system in real time. Therefore, in this study, we developed an Android-based mobile application that can measure concentration during study by using functional near-infrared spectroscopy, which is used to measure brain activity. First, the task accuracy was predicted at a maximum level of 93.75% from the prefrontal oxygenation characteristics measured while performing the visual Q&A task on 11 college students, and a concentration calculation formula based on a linear regression model was derived. Then, a survey on the usability of the mobile application was conducted, overall high satisfaction and positive opinions were obtained. From these findings, this application can be used as a customized learning aid application for users, and further, it can help educators improve the quality of classes based on the level of concentration of learners.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1519-1519
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• 2001

The aim of this work was to test the feasibility of NIRS in analysing textural characteristics of “Pasta Filata” cheese during the shelf-life. For this purpose, 128 samples of “Pasta Filata” cheese, subdivided into two sets on the basis of the wax used to avoid mechanical damages (paraffin, biodegradable wax), were analysed by using an InfraAlyzer 500 (Bran+Luebbe). Analyses were performed at room temperature. Samples were cut into small cylinders (D=3.2 cm, height = 1 cm), in agreement with literature information. Data were processed by using Sesame Software (Bran+Luebbe). Samples were analysed, during the shelf-life, at 90 and 120 days. In parallel, textural characteristics were detected carrying out a compression method by using an Universal Testing Machine Instron model 4301 (Instron Corporation, Canton, Massachusetts). As compression probe was used a cylinder (D = 5.8 cm, height = 3.7 cm) and a speed rate of 20mm/min was applied. The load at 20 mm of compression was recorded on sample cylinders of 1.7 cm (D) by 2 cm (height). Qualitative analysis of full spectra showed the possibility to gather samples on the basis of the days of shelf-life. The textural characteristics of cheese during the shelf-life was evaluated by comparing NIRS data with rheological results. The best correlation was obtained applying MLR to the first derivative of normalized absorbance values at seven wavelengths. Load values were plotted against the NIR prediction values based on first derivatives. NIRS proved to be an useful tool in classifying samples on the basis of the shelf-life period as well as in predicting their textural characteristics ($R^2$= 0.916, SEC = 0.192, SEP = 0.248, SEV = 0.345).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.296-300
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• 2012

Discrimination of geographic origin of agricultural products is a important issue in Korea because the price difference between Korean domestic and imported cereals is a key among some reasons. NIRS (Near Infrared Reflectance Spectroscopy) has been applied to classify the geographical origin of soybeans. Total 135 samples (Korean domestic 92 and foreign 43) were used to obtain calibration equation through 400~2,500 nm wavelength. The math treatment with 1st derivative and 4 nm gap and the modified partial least squares(MPLS)regression was outstanding for calibration equation. The standard error of calibration and determination coefficient in calibration set(n=115) was 6.65 and 0.98, respectively. And it showed that the extra 20 samples for validation equation were identified their authentication correctly. This study describes that the application of NIRS would be possible for discrimination of geographical origin between Korean domestic and imported soybeans.

• Journal of Animal Environmental Science
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• v.20 no.3
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• pp.117-124
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• 2014

The objectives were to assess the use of near-infrared reflectance spectroscopy (NIRS) as a tool for estimating nutrient compositions of corn kernel, and to apply an NIRS-based indium gallium arsenide array detector to the system for collecting spectra and analyzing calibration equations using equipments designed for field application. Partial Least Squares Regression (PLSR) was employed to develop calibration equations based on representative data sets. The kennard-stone algorithm was applied to induce a calibration set and a validation set. As a result, the method for structuring a calibration set significantly affected prediction accuracy. The prediction of chemical composition of corn kernel resulted in the following (kennard-stone algorithm: relative) moisture ($R^2=0.82$, RMSEP=0.183), crude protein ($R^2=0.80$, RMSEP=0.142), crude fat ($R^2=0.84$, RMSEP=0.098), crude fiber ($R^2=0.74$, RMSEP=0.098), and crude ash ($R^2=0.81$, RMSEP=0.048). Result of this experiment showed the potential of NIRS to predict the chemical composition of corn kernel.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.49 no.3
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• pp.211-215
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• 2004

Near infrared reflectance spectroscopy (NIRS) is a rapid and accurate analytical method for determining the composition of agricultural products and feeds. This study was conducted to determine tocopherol and tocotrienol contents in rice bran by using NIRS system. Total 80 rice bran samples previously analyzed by HPLC were scanned by NIRS and over 60 samples were selected for calibration and validation equation. A calibration equation calculated by MPLS(modified partial least squares) regression technique was developed and coefficient of determination for tocopheyol and tocotyienol content were 0.975 and 0.984, respectively, in calibration sets. Each calibration equation was fitted to validation set that was performed with the remaining samples not included is the calibration set, which showed high positive correlation both in tocopherol and tocotrienol content file. This results demonstrate that the developed NIRS equation can be practically used as a rapid screening method for quantification of tocopherol and tocotrienol contents in rice bran.