• Journal of the Korean Wood Science and Technology
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• v.45 no.2
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• pp.202-212
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• 2017

This study was to establish the interrelation between chemical compositions and near infrared (NIR) spectra for the classification on distinguishability of domestic gymnosperms. Traditional wet chemistry methods and infrared spectral analyses were performed. In chemical compositions of five softwood species including larch (Larix kaempferi), red pine (Pinus densiflora), Korean pine (Pinus koraiensis), cypress (Chamaecyparis obtusa), and cedar (Cryptomeria japonica), their extractives and lignin contents provided the major information for distinction between the wood species. However, depending on the production region and purchasing time of woods, chemical compositions were different even though in same species. Especially, red pine harvested from Naju showed the highest extractive content about 16.3%, whereas that from Donghae showed about 5.0%. These results were expected due to different environmental conditions such as sunshine amount, nutrients and moisture contents, and these phenomena were also observed in other species. As a result of the principal component analysis (PCA) using NIR between five species (total 19 samples), the samples were divided into three groups in the score plot based on principal component (PC) 1 and principal component (PC) 2; group 1) red pine and Korean pine, group 2) larch, and group 3) cypress and cedar. Based on the chemical composition results, it was concluded that extractive content was highly relevant to wood classification by NIR analysis.

• Preventive Nutrition and Food Science
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• v.21 no.4
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• pp.393-397
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• 2016

Whole grain wheat flour (WGWF) is the entire grain (bran, endosperm, and germ) milled to make flour. The WGWF of 31 Korean wheat (Triticum aestivum L.) cultivars were analyzed for the chemical compositions, and classified into groups by hierarchical cluster analysis (HCL). The average composition values showed a substantial variation among wheat varieties due to different wheat varieties. Wheat cv. Shinmichal1 (waxy wheat) had the highest ash, lipid, and total dietary fiber contents of 1.76, 3.14, and 15.49 g/100 g, respectively. Using HCL efficiently classified wheat cultivars into 7 clusters. Namhae, Sukang, Gobun, and Joeun contained higher protein values (12.88%) and dietary fiber (13.74 %). Regarding multi-trait crop breeding, the variation in chemical compositions found between the clusters might be attributed to wheat genotypes, which was an important factor in accumulating those chemicals in wheat grains. Thus, once wheat cultivars with agronomic characteristics were identified, those properties might be included in the breeding process to develop a new variety of wheat with the trait.

• Journal of information and communication convergence engineering
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• v.21 no.3
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• pp.208-215
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• 2023

Deep learning techniques provide powerful solutions to several pattern-recognition problems, including Raman spectral classification. However, these networks require large amounts of labeled data to perform well. Labeled data, which are typically obtained in a laboratory, can potentially be alleviated by data augmentation. This study investigated various data augmentation techniques and applied multiple deep learning methods to Raman spectral classification. Raman spectra yield fingerprint-like information about chemical compositions, but are prone to noise when the particles of the material are small. Five augmentation models were investigated to build robust deep learning classifiers: weighted sums of spectral signals, imitated chemical backgrounds, extended multiplicative signal augmentation, and generated Gaussian and Poisson-distributed noise. We compared the performance of nine state-of-the-art convolutional neural networks with all the augmentation techniques. The LeNet5 models with background noise augmentation yielded the highest accuracy when tested on real-world Raman spectral classification at 88.33% accuracy. A class activation map of the model was generated to provide a qualitative observation of the results.

• Analytical Science and Technology
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• v.33 no.2
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• pp.86-97
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• 2020

Reconstruction and separation of explosive-contaminated overlapping fingerprints constitutes an analytical challenge of high significance in forensic sciences. Laser-induced breakdown spectroscopy (LIBS) allows real-time chemical mapping by detecting the light emissions from laser-induced plasma and can offer powerful means of fingerprint classification based on the chemical components of the sample. During recent years LIBS has been studied one of the spectroscopic techniques with larger capability for forensic sciences. However, despite of the great sensitivity, LIBS suffers from a limited detection due to difficulties in reconstruction of overlapping fingerprints. Here, the authors propose a simple, yet effective, method of using chemical mapping to separate and reconstruct the explosive-contaminated, overlapping fingerprints. A Q-switched Nd:YAG laser system (1064 nm), which allows the laser beam diameter and the area of the ablated crater to be controlled, was used to analyze the chemical compositions of eight samples of explosive-contaminated fingerprints (featuring two sample explosive and four individuals) via the LIBS. Then, the chemical validations were further performed by applying the Raman spectroscopy. The results were subjected to principal component and partial least-squares multivariate analyses, and showed the classification of contaminated fingerprints at higher than 91% accuracy. Robustness and sensitivity tests indicate that the novel method used here is effective for separating and reconstructing the overlapping fingerprints with explosive trace.

• Korean Journal of Oriental Medicine
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• v.3 no.1
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• pp.153-167
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• 1997

Conventionally, identification and classification methods of natural products include the morphological survey and assay of chemical disposition, sing these methods, however, is not satisfying for the precise identification of natural products because they are often valiable in the compositions and morphology To standardize the natural products identification and classification, genomic DNA analysis such as RAPD, RFLP and Amp-FLP can be adopted for this purpose. In this study, various ginsengs and bear gall bladder were tested for the development of genetic identification and classification method. Varieties of ginsengs such as, P. ginseng, P. quinquefolium, P. japonicus and P. notoginseng, were genetically analyzed by RAPD. Also, DNA isolated from Bear blood and gall bladder, Ursus thibetanus, Ursus americanus and Ursus arctos, were analyzed by the same method. The results demonstrated that the identification and classification of bear gall bladder and various ginsengs were possible by RAPD analysis. Therefore, this method was thought to be used as a additional method for the identification and classification of other natural products.

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.3
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• pp.179-186
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• 2014

Weathering indexes of the typical pedons derived from different parent materials of the soils of Korea were calculated by Kronberg and Nesbitt (1981) to understand weathering degree of the soils which might give a clue of soil formation and characterizing a soil pedon. The weathering index W1 was chemical change index, and the weathering index W2 was silicate dominant index. The chemical compositions of the 49 typic pedons were extracted from the Taxonomical Classification of Korean Soils (NIAST, 1999). The weathering indexes of Kimhae series, derived from fluvio marine material, were the highest among the analyzed soils. Within parent materials, the weathering indexes of the soils derived from limestones parent materials were high, and those derived from phorphyry materials were low. The relationship between W1 and W2 showed unique pattern which implied certain sequence within the same parent materials.

• Journal of the Korean Wood Science and Technology
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• v.47 no.4
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• pp.509-518
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• 2019

This study analyzed the effect of organic solvent extractives on the classification of wood species via near-infrared spectroscopy (NIR). In our previous research, five species of Korean softwood were classified into three groups (i.e., Cryptomeria japonica (cedar)/Chamaecyparis obtuse (cypress), Pinus densiflora (red pine)/Pinus koraiensis (Korean pine), and Larix kaempferi (Larch)) using an NIR-based principal component analysis method. Similar tendencies of extractive distribution were observed among the three groups in that study. Therefore, in this study, we qualitatively analyzed extractives extracted by an organic solvent and analyzed the NIR spectra in terms of the extractives' chemical structure and band assignment to determine their effect in more detail. Cedar/cypress showed a similar NIR spectra patterns by removing the extractives at 1695, 1724, and 2291 nm. D-pinitol, which was detected in cedar, contributed to that wavelength. Red pine/Korean pine showed spectra changes at 1616, 1695, 1681, 1705, 1724, 1731, 1765, 1780, and 2300 nm. Diterpenoids and fatty acid, which have a carboxylic group and an aliphatic double bond, contributed to that wavelength. Larch showed a catechin peak in gas chromatography and mass spectroscopy analysis, but it exhibited very small NIR spectra changes. The aromatic bond in larch seemed to have low sensitivity because of the 1st overtone of the O-H bond of the sawdust cellulose. The three groups sorted via NIR spectroscopy in the previous research showed quite different compositions of extractives, in accordance with the NIR band assignment. Thus, organic solvent extractives are expected to affect the classification of wood species using NIR spectroscopy.

• Korean Journal of Radiology
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• v.22 no.1
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• pp.86-96
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• 2021

CT is a diagnostic tool with many clinical applications. The CT voxel intensity is related to the magnitude of X-ray attenuation, which is not unique to a given material. Substances with different chemical compositions can be represented by similar voxel intensities, making the classification of different tissue types challenging. Compared to the conventional single-energy CT, spectral CT is an emerging technology offering superior material differentiation, which is achieved using the energy dependence of X-ray attenuation in any material. A specific form of spectral CT is dual-energy imaging, in which an additional X-ray attenuation measurement is obtained at a second X-ray energy. Dual-energy CT has been implemented in clinical settings with great success. This paper reviews the theoretical basis and practical implementation of spectral/dual-energy CT.

• Journal of Conservation Science
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• v.33 no.5
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• pp.331-344
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• 2017

In this study, glass beads from Osan Sucheong were classified according to color into 10 groups. Among these groups, reddish brown, bluish green, and purplish blue were identified as the main colors of glass beads based on their large quantities in Osan Sucheong. The glass beads of these main colors were then classified according to their chemical compositions and and looked at the changing process. Based on the results, reddish brown and bluish green glass beads can both be divided into five types, and purplish blue glass beads can be divided into four types. Furthermore, according to continuity of type, it was identified as the main attributes that the reddish brown beads belong to two types, whereas the bluish green and purplish blue each belong to one type. Based on a review of primary attributes, beads of these three colors were identified as soda glass and high-alumina glass. The results indicate that these beads came from a single, consistent route of origin into the region. However, it is possible that glass beads came through various routes into Osan Sucheong in the $4^{th}$ century, because many types of chemical compositions have been detected for beads from this time.

• Applied Chemistry for Engineering
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• v.16 no.1
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• pp.21-27
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• 2005

In order to conduct research on oil originated in Mongolia for further application of petroleum not only as fuel but also as raw material for organic synthesis, we need to study the physical, chemical characteristics and individual, group hydrocarbon's compositions of main petroleum fractions. A number of studies and surveys on the physical and chemical characteristics, group hydrocarbon's composition of petroleum deposits in Zuun-Bayan, Sukhaibulag, Tsagaan Elst, Tamsagbulag have been carried out earlier through n-g-M, aniline point and dispersimetric methods successfully. Yet a detailed chromatographical and NMR spectroscopic study for the individual hydrocarbon's composition of Tamsagbulag oil main fractions has not been conducted. In the present study the results of GC analyses of gasoline fractions of wells 19-3, 19-13 and 19-10, Tamsagbulag (Eastern Mongolia) were presence. The gasoline fractions of given wells were characterized by the high concentration of paraffins and presence of trace amount of olefins. There were identified 69 paraffins, 45 naphthenes, 41 aromatics and 3 olefins in total 158 individual hydrocarbons from each samples of gasoline fraction. The first attempts to classify Tamsagbulag oil under the individual hydrocarbon's composition data were successfully conducted and the supposition of a genetic classification of given oil as "sapropelic" type was made.