• Korean Journal of Agricultural Science
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• v.48 no.2
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• pp.299-310
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• 2021

Glycerol is a non-volatile compound with no aromatic properties that contributes significantly to the quality of wine by providing sweetness and richness of taste. In addition, it is also the third most significant byproduct of alcoholic fermentation in terms of quantity after ethanol and carbon dioxide. In this study, Fourier transform infrared (FT-IR) spectroscopy was employed as a fast non-destructive method in conjugation with multivariate regression analysis to build a model for the quantitative analysis of glycerol concentration in wine samples. The samples were prepared by using three varieties of red wine samples (i.e., Shiraz, Merlot, and Barbaresco) that were adulterated with glycerol in concentration ranges from 0.1 to 15% (v·v^-1), and subjected to analysis together with pure wine samples. A net analyte signal (NAS)-based methodology, called hybrid linear analysis in the literature (HLA/GO), was applied for predicting glycerol concentrations in the collected FT-IR spectral data. Calibration and validation sets were designed to evaluate the performance of the multivariate method. The obtained results exhibited a high coefficient of determination (R²) of 0.987 and a low root mean square error (RMSE) of 0.563% for the calibration set, and a R² of 0.984 and a RMSE of 0.626% for the validation set. Further, the model was validated in terms of sensitivity, selectivity, and limits of detection and quantification, and the results confirmed that this model can be used in most applications, as well as for quality assurance.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.57 no.1
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• pp.10-24
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• 2021

A seasonal characteristic of fish assemblages in the coastal waters of Gapa-do was determined using samples collected by a trammel net from 2015 to 2019. Annual mean temperature and salinity were 18.9℃, 33.6 psu (2015), 19.5℃, 33.6 psu (2016), 18.9℃, 33.8 psu (2017), 18.8℃, 34.5 psu (2018) and 19.5℃, 33.7 psu (2019), which show a stable water mass. During the survey period, a total of 50 species (30 families and 8 orders) of fishes were identified, including Scorpaeniformes (3 families and 9 species) and Perciformes (18 families and 29 species) that accounted for 68% of the total number. The number of species was higher in summer than in winter, showing the peak in the summer by 35 species and the low in the winter by 20 species. The number of individuals and the biomass peaked in the summer by 690 individuals and 151.4 kg, and were the lowest in the autumn by 336 individuals and 76.6 kg. The annual diversity index, evenness index and richness index were appeared to be 2.54-2.75, 0.68-0.76 and 5.32-6.65 at each stations. The dominance index was appeared to be the highest in 2018 and the lowest in 2015. Marbled rockfish (Sebastiscus marmoratus), rock fish (Sebastes inermis), filefish (Stephanolepis cirrhifer), rabbit fish (Siganus fuscescens), porcupine fish (Diodon holocanthus) and smallscale blackfish (Girella melanichthys) were dominant species, which occurred abundantly during the entire survey period. Subtropical fishes were identified as a total of 24 species (48.0%) and the number of species was higher in 2019 by 20 (60.6%) species and lower in 2015 by 13 (44.8%) species. The dominant species of the subtropical fishes were appeared to be rabbit fish, porcupine fish, smallscale blackfish, flag fish (Goniistius zonatus), stripey (Microcanthus strigatus), grunter (Parapristipoma trilineatum), and bluestriped angelfish (Chaetodontoplus septentrionalis) at the study sites.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.667-677
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• 2020

This study was conducted to investigate the fish fauna and characteristics of the Carassius auratus population in the Boryeong Reservoir in Chungcheongnam-do from October 2017 to June 2018. The collected fish were identified as 3,506 individuals of 15 species from a total of nine families. The dominant and subdominant species were H. nipponensis with 1,706 (48.6%) individuals and C. auratus with 1,021 (29.1%) individuals, respectively. The biomass of C. auratus (246,130g), P. fulvidraco(50,610g), C. cuvieri (14,730 g), S. asotus (11,560 g), and C. carpio (10,930 g) was analyzed. The results of the community analysis showed a dominant index value of 0.87 (±0.2), a diversity index value of 0.78 (±0.5), an evenness index value of 0.47 (±0.2), and a richness index value of 0.99 (±0.5). The length-weight analysis of C. auratus showed a regression coefficient b of 3.06, and a condition factor (K) of 0.0004 with a positive slope. The frequency distribution of the total length analysis of the C. auratus population inhabiting the Boryeong Reservoir showed a high distribution of lengths between 140-160 mm and a low distribution between 230-280 mm. The normalized difference water index (NDWI) was analyzed over the Boryeong Reservoir water surface from 2013 to 2014 using Landsat 8 channel data. The areas where the NDWI was decreased were located at the inflow site of Ungcheon Stream.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.714-723
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• 2020

This study was conducted to investigate the community stability and similarity of benthic macroinvertebrates in the Giran stream between August and September 2018, and compare results to those reported by Lee (2004). As relates to the total number of species in each taxon in 2018, 45 species were additionally discovered compared to the 2003 study; the number of EPT taxa increased by 14 species and OCH taxa increased by 18 species. The diversity and richness indexes increased while the dominance index tended to decrease. According to analysis of functional feeding groups, 11 more Gathering-collector species were found, making it the highest functional feeding group with 24 species. According to analysis of functional habitat groups, 15 more clinger species were found than in the past, making it the highest functional habitat group with 41 species. A community stability comparison showed that species belonging to 'Stability Group I' had the highest stability rate at 57.1% in 2003 and 61.5% in 2018. According to the biological water quality assessment, in 2018, the average water quality level at each survey site was 'Ia' and 'Very Good' in terms of environmental conditions. As a result of the similarity analysis between the survey points for the species that appeared, two large groups of similarities were classified (similarity group 1: 2003 sites, similarity group 2: 2018 sites).

• Journal of The Korean Association For Science Education
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• v.41 no.1
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• pp.59-70
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• 2021

Ability to make informed decisions by critically evaluating media information on socioscientific issues (SSI) is one of the crucial elements of scientific literacy that citizens should obtain. This study aims to investigate how middle school students evaluated media information about socioscientific issues (SSI) when they faced two different types of information (i.e., numerical and empathic information). To achieve the aim, 96 middle school students responded to the questionnaires asking them to evaluate reliability and persuasiveness of SSI media information. The questionnaires consisted of two sets of newspaper articles on each SSI (pro-numerical/empathic, against-numerical/empathic). After reading the articles, the students evaluated reliability and persuasiveness of each article and wrote the reasons for their evaluation. The results were as follows: First, the students believed that news articles with numerical information were more reliable than the ones with empathic information in all SSI contexts. They tended to trust scientific evidence and data from numerical information, and real cases, societal problems, expressions, and values from empathic information. In addition, they evaluated their reliability based on the logic of information, accuracy of information, breadth and depth of data, and quantity and quality of sources both numerical and empathic information. Second, in case of evaluating persuasiveness of the articles, they focused more on the values that information contained, richness and logicality of the information, rather than the types of information, regardless of the type of information.

• Journal of Apiculture
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• v.34 no.3
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• pp.197-206
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• 2019

Pollination is an important ecosystem service involved in plant breeding and reproduction. This study analyzed the pollination network, which is the interaction between flowering plants and flower-visiting insects in the agricultural landscape. Flower-visiting insects from blossoms of flowering crops and surrounding plants were quantitatively surveyed during summer time. The pollinator species and abundance on each flowering plant were analyzed. A total of 2,381 interactions were indentified with 154 pollinators on 30 species of plants. Species richness of the pollinators was highest in Coleoptera (34%) followed by Hymenoptera (28%), Diptera (28%) and Lepidoptera (10%). Apis mellifera dominated (50%) followed by Calliphora vomitoria (5.3%) and Xylocopa appendiculata among pollinators, and remaining wild pollinators provided complex interaction. Among plants, Platycodon grandiflorum, Perilla frutescen and Fagopyrum esculentum harbored most pollinators and showed highest interaction frequencies. In the modular analysis, Apis mellifera was located as a hub-species which connect the interaction of others, implying most important role in the network. This results provide the basic information on the pollinator species associated with each crop and pollinator habitat in which plant provide the nectar, pollen and habitat resources for wild pollinators.

• Korean Journal of Heritage: History & Science
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• v.54 no.1
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• pp.32-51
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• 2021

Architectural evidence of Gaya is insignificant than any other area. In this situation, house-shaped earthenware is particularly helpful in the study of Gaya architecture. However, house-shaped earthenware is not a building, it has just the shape of buildings. So, we have to find out architectural evidence from that. In this paper, I tried to estimate the architectural characteristics of Gaya through house-shaped earthenware in detail. I also consulted historical records, archeological results, and other scholars' papers. The results are as follows. First, house-shaped earthenware can be classified into three types according to its shape, and each type has distinct architectural structural characteristics. Second, house-shaped earthenware generally has a gambrel roof, and the characteristic of architectural design with the gable side of the gambrel roof as a front is the biggest feature of Gaya architecture. Third, various types of buildings existed according to their functions in Gaya architecture, and house-shaped earthenware was showed buildings of ancient storage, pens, and residences, which are symbols of the richness among various types of buildings.

• Journal of Microbiology and Biotechnology
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• v.32 no.3
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• pp.294-301
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• 2022

In our greenhouse experiment, soil heat treatment groups (50, 80, and 121℃) significantly promoted growth and disease suppression of Panax notoginseng in consecutively cultivated soil (CCS) samples (p < 0.01), and 80℃ worked better than 50℃ and 121℃ (p < 0.01). Furthermore, we found that heat treatment at 80℃ changes the microbial diversity in CCS, and the inhibition ratios of culturable microorganisms, such as fungi and actinomycetes, were nearly 100%. However, the heat-tolerant bacterial community was preserved. The 16S rRNA gene and internal transcribed spacer (ITS) sequencing analyses indicated that the soil heat treatment had a greater effect on the Chao1 index and Shannon's diversity index of bacteria than fungi, and the relative abundances of Firmicutes and Proteobacteria were significantly higher than without heating (80 and 121℃, p < 0.05). Soil probiotic bacteria, such as Bacillus (67%), Sporosarcina (9%), Paenibacillus (6%), Paenisporosarcina (6%), and Cohnella (4%), remained in the soil after the 80℃ and 121℃ heat treatments. Although steam increased the relative abundances of most of the heat-tolerant microbes before sowing, richness and diversity gradually recovered to the level of CCS, regardless of fungi or bacteria, after replanting. Thus, we added heat-tolerant microbes (such as Bacillus) after steaming, which reduced the relative abundance of pathogens, recruited antagonistic bacteria, and provided a long-term protective effect compared to the steaming and Bacillus alone (p < 0.05). Taken together, the current study provides novel insight into sustainable agriculture in a consecutively cultivated system.

• Knowledge Management Research
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• v.23 no.1
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• pp.203-225
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• 2022

Competition in the OTT (Over the Top) service market is getting fiercer since global OTT services enter the domestic market and existing platforms are actively reorganized. As powerful competitors with ultra-luxurious content continue to enter the marke with diversity required by users, various efforts are required for OTT service platforms to prevent subscriber churn in order to generate continuous revenue. Thus, this study tried to examine the effect of OTT service characteristics on continuous use intention through an empirical analysis based on Expectation-Confirmation Model(ECM). A total of 386 responses were collected from individuals who have experience or are currently using OTT service and analyzed using AMOS 24. Results show that content curation, content richness, and audience activity had a significant effect on expectation confirmation. Also, expectation confirmation had a significant effect on perceived usefulness and user satisfaction while perceived usefulness had a significant effect on user satisfaction, significantly influencing continuous intention to use OTT. Finally, price fairness was found to strengthen all proposed relationships. The findings are expected to provide useful information for service and content development for subscriber retention, which has the most direct impact on revenue generation of OTT service providers.

• Journal of Life Science
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• v.32 no.10
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• pp.803-811
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• 2022

Despite the importance of traditional Korean fermented foods, little is known about the microbial communities and diversity of fermented soy products. To gain insight into the unexplored microbial communities of both Doenjang (DJ) and Ganjang (GJ) that may contribute to the fermentation in Korean traditional foods, we carried out next-generation sequencing (NGS) based on the V3-V4 region of 16S rDNA gene analysis. The alpha diversity analysis results revealed that both the Shannon and Simpson diversity indices were significantly different between the two groups, whereas the richness indices, including ACE, CHAO, and Jackknife, were not significant. Firmicutes were the most dominant phylum in both groups, but several taxa were found to be more abundant in DJ than in GJ. The proportions of Bacillus, Kroppenstedtia, Clostridium, and Pseudomonas and most halophiles and halotolerant bacteria, such as Tetragenococcus, Chromohalobacter, Lentibacillus, and Psychrobacter, were lower in DJ than in GJ. Linear discriminant effect size (LEfSe) analysis was carried out to discover discriminative functional biomarkers. Biomarker discovery results showed that Bacillus and Tetragenococcus were identified as the most important features for the classification of subjects to DJ and GJ. Paired-permutational multivariate analysis of variance (PERMANOVA) further revealed that the bacterial community structure between the two groups was statistically different (p=0.001).