• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.165-168
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• 2006

Fourier transform-near infrared spectroscopy (FT-NIRS) was evaluated for determination of total dietary fiber (TDF) content of brown rice. Enzymatic-gravimetric method was suitable to obtain reference values for calibration of NIR at 1,000-2,500 nm range. Standard error of laboratory procedure ranged 0.17 to 0.72%. Partial least square (PLS) regression was used to develop the calibration equations. Regression was performed automatically using NIRCal chemometric software. Accuracy of prediction model for TDF content was certified for regression coefficient (r), standard error of estimation (SEE) and standard error of prediction (SEP), showing 0.9780, 0.0636, and 0.0642, respectively. This prediction model can be used for determination of TDF in brown rice and would be useful for real-time analysis in food industry.

• Analytical Science and Technology
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• v.30 no.5
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• pp.234-239
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• 2017

Identifying the components of residues that are not completely burned at the sites of fires site can provide valuable information for tracing the causes of fires. In order to clarify the types of plastic combustion residues found at the scenes of fires, we studied the residue formed after the combustion of polyethylene (PE) and acrylonitrile butadiene styrene (ABS). Plastic samples were burned at 200, 300, 350, 400, and $500^{\circ}C$ for 3 min using a cone calorimeter, and the changes in weight and combustion products were observed. The powder products obtained by lyophilization and pulverization of the combustion products obtained at each temperature were analyzed by a Fourier transform-near infrared (FT-NIR) spectrometer. When the PE samples were burned, the weight did not change up to $350^{\circ}C$, however a significant change in the weight could be measured above $400^{\circ}C$. The principal component analysis (PCA) of the FT-NIR spectra of the PE and ABS samples obtained at each temperature confirmed that the combustion residues at each temperature were PE and ABS, respectively. Therefore, the types of unburned plastics found at the sites of fires can be confirmed rapidly by near infrared spectroscopy.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1158-1158
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• 2001

Fast and dynamic biochemical, enzymatic and morphological changes occur during the so-called generative development and during the vegetative processes in seeds. The most characteristic biochemical and compositional changes of this period are the formation and decline of storage components or their precursors, the change of their degree in polymerization and an extensive change in water content. The aim of the present study was to detect the maturation processes in seed nondestructively and to verify the applicability of near infrared spectroscopic methods in the measurement of physiological, chemical and biochemical changes in wheat seed. The amount and variation of different water “species” has been changed intensively during maturation. Characteristic changes of three water absorption bands (1920, 1420 and 1150 nm) during maturation were analysed. It was concluded that the free/bound transition of water molecules could be followed sensitively in different region of NIR spectra. Kinetic changes of carbohydrate reserves were characteristic during maturation. An intensive formation and decline of carbohydrate reserves were observed during early stage of maturation (0 -13 days, high energy demand). An accelerated formation of storage carbohydrates (starch) was detected in the second phase of maturation. Five characteristic absorption bands were analysed which were sensitive indicators the changes of carbohydrates occurred during maturation. Precursors of protein synthesis and the synthesis of reserve proteins and their kinetic changes during maturation were followed from NIR spectra qualitative and qualitatively. Dynamic formation of amino acids and the changes of N forms were detected by spectroscopic, chromatographic and by capillary electrophoresis methods. Calibration equations were developed and validated in order to measure the optimal maturation time protein and moisture content of developing wheat seeds. The spectroscopic methods are offering chance and measurement potential in order to detect fine details of physiological processes. The spectra have many hidden details, which can help to understand the biochemical background of processes.

• The Bulletin of The Korean Astronomical Society
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• v.35 no.1
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• pp.68.2-68.2
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• 2010

We present near-infrared (NIR) spectra of 6 young stellar objects (YSOs) around the supernova remnant G54.1+0.3 obtained with TripleSpec, a slit-based NIR cross-dispersion echelle spectrograph on th 5-m Palomar Hale telescope covering the entire NIR atmospheric window of 1-2.4 micron. These YSOs, whose formation was possibly triggered by the progenitor of G54.1+0.3, show significant mid-infrared (MIR) excess and have been proposed to be late O- and early B-type YSOs based on their spectral energy distribution. Our TripleSpec observations reveal the existence of strong H and He I lines, consistent with the previous interpretation of their spectral types, while the absence of Br-gamma emission line indicates that the YSOs do not have a nearby circumstellar disk. We discuss the relation between these YSOs and G54.1+0.3 based on the TripleSpec data and previous photometric data as well.

• Food Science and Preservation
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• v.21 no.6
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• pp.838-843
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• 2014

In this study, near-infrared spectroscopy was used to observe the drying non-uniformity of vegetables such as spring onions, onions, and garlic, which are commonly used for seasoning. For the warm-air convection drying method, the vegetables showed drying non-uniformity, which is due to the unevenness of the wind temperature and humidity depending on the height and position of the drying tray. The second derivative spectra between the vegetable samples with different drying degrees were compared. The peak at around 1,390~1,400 nm, which is assigned to weak hydrogen bonds of water, was changed during drying whereas the peak near 1,420 nm, which represents strong hydrogen (H-) bonds of water, was not changed, indicating that water with weak H-bonds evaporates first during drying, and that water with strong H-bonds remains after drying. The hyperspectral NIR imaging technique combined with principal-component analysis made it possible to discriminate the dried vegetables according to their drying degree.

• Clean Technology
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• v.18 no.3
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• pp.265-271
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• 2012

The use of renewable energies has been required to diminish the dependency on fossil fuels. As one of clean energy sources biomass has been extensively studied because various biomass resources necessitated rapid characterization of their chemical and physical properties in an on-line or real-time basis. For such an analysis near-infrared (NIR) spectroscopy has been successfully applied because of its non-invasive and informative characteristics. In this work, the applicability of nonlinear chemometric techniques based on biomass near infrared (NIR) data is evaluated for the rapid prediction of ash/char contents in different types of biomass. The prediction results of various prediction models and the effect of using preprocessing methods for NIR data are compared using six types of biomass NIR data. The results showed that nonlinear prediction models yielded better prediction performance than linear ones. It also turned out that by adopting the use of proper preprocessing methods the performance of prediction of biomass properties improved.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.240-246
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• 1998

Geographical origin of the Korean, Chinese and Japanese sesame seeds were identified very high accuracy by NIR spectroscopy. The NIR instrument of filter type showed the same accuracy of the monochromator scanning type to identify the geographical origin of the sesame seeds. In case of adulteration between the Korean and Chinese sesame seeds, the ratio of addition could be determined about 10% error level. The reason of identification of geographical origin by NIR spectroscopy, it was supposed to the difference, of oil cake substance.

• The Bulletin of The Korean Astronomical Society
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• v.44 no.1
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• pp.44.4-44.4
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• 2019

The supernova remnant Cassiopeia A (Cas A) provides a unique opportunity to observe the fine details of the explosion of core-collapse supernova (SN). Previous optical and near-infrared (NIR) observations of Cas A have shown that the spatial distribution of the metal-enriched SN ejecta is very complicated, indicating that the SN explosion should have been asymmetric and turbulent, especially near the core. Recently, we obtained a long-exposure (~10 hr) image of Cas A by using the UKIRT 3.6-m telescope with a narrow-band filter centered at [Fe II] 1.644 um emission. This 'deep [Fe II] image' provides an unprecedented panoramic view of Cas A, revealing the distribution of dense SN ejecta over the entire remnant. We have carried out NIR multi-object spectroscopic observations of the dense ejecta knots in the northeastern (NE) and eastern (E) outer regions of the remnant using the MMIRS attached on the MMT 6.5-m telescope. A total of 67 ejecta knots are detected. By analyzing their spectra, we have found that the knots in the NE area show strong [S II]/[S III] and [Fe II] lines but little or no [P II] line, while those in the E outer region show strong [Fe II] lines but weak [S II]/[S III] lines. In this talk, we present the preliminary results of our NIR spectroscopic observations and discuss the implications.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1266-1266
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• 2001

Pasture composition, an important attribute determining sward condition and value, is normally assessed by hand separation, drying and measuring weight contribution of each species in the mixture. This is a tedious, time and labour consuming procedure. NIRS has demonstrated the potential for predicting botanical composition of swards, but most of the work has been carried out on dry samples. The aim of this work was to evaluate the feasibility of developing NIR models for predicting the white clover and ryegrass content in fresh or dry mixtures artificially prepared from pure samples of both species. Mixtures from pure stands of white clover(Trifolium repens) and perennial ryegrass (Lolium perenne) were prepared with different proportions (0 to 100%) of each species (fresh weight). A total of 55 samples were made (11 mixtures,5 cuts). Spectra (400 to 2500 nm) were taken from fresh chopped (rectangular cuvettes, transport sample module) samples, in a NIR Systems 6500 scanning monochromator controlled by the software NIRS 3 (Infrasoft International), which was also utilized for calibration development. Different math treatments (derivative order, subtraction gap and smooth segment) and a scatter correction treatment of the spectra (SNV and Detrend) were tested. Equations were developed by modified partial least squares. Prediction accuracy evaluated by cross-validation, showed that percentage of clover or ryegrass, as contribution in dry weight, can be successfully percentage of clover or ryegrass, as contribution in dry weight, can be successfully predicted either on fresh or dried samples, with equations developed by different math treatments. Best equations for fresh samples were developed including a first, second, or third derivative, whereas for dry samples best equations included a second or third derivative. Standard errors of ross validation were about 6% for fresh and 3.6% for dry samples, Coefficient of determination of cross validation (1-VR) were over 0.95 times the value of SECV for fresh samples and over 8 times the value of SECV for dry samples. Scatter correction (SNV and Detrend) in general improved prediction accuracy. It is concluded more precise on dried and ground samples, it can be used with an acceptable error level and less time and labour, on fresh samples.

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.405.1-405.1
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• 2002

The amount of water for the cultivation of citrus is different based on the growing period. The water content in the leaves of citrus can be a index for watering during cultivation. The purpose of this study is to determine non-destructively the water content of Citrus leaves by using near infrared spectroscopy (NIRS). Citrus leaves were prepared from satsuma mandarin leaves (Citrus unshiu Marc. var. okitsu) ranging from 62.20 to 69.98% of water content by loss on drying, NIR reflectance spectra of Citrus leaves were acquired by using a fiber optic probe. (omitted)