• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.103-103
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• 2022

다복찰은 전라북도농업 기술원에서 2012~2020년에 신명흑찰과 익산488호를 교배하여 육성한 찰벼이며, 중대립, 단간, 내도복, 다수성의 특징을 보인다. 동진찰은 1998년도에 육성되었으며, 우리나라에서 가장 인기 있는 찰벼이다(재배면적 25,161ha/2021년 기준). 드문모심기 재배 기술은 2017년부터 도입되었으며, 밀파 육묘하여 재식밀도 및 재식주수를 감소함으로써 소요되는 재료비 등 경비 및 투입되는 노동력을 절감하는 경제성 있는 기술이다. 따라서 본 연구는 전라북도농업기술원에서 육성한 다복찰 보급 확대 및 가장 인기 높은 동진찰의 드문모심기 재배기술 확립 일환으로 시작되었으며, 2024년까지 3년간 실시할 계획이다. 시험은 기술원 논 포장에서 실시하였으며, 시험품종은 다복찰, 동진찰, 시험요인은 이앙시기(3처리) 및 재식밀도(4처리)를 두었다. 이앙시기별로 이앙 17일 전에 온탕소독(62℃, 10분), 종자소독(32℃, 1일), 침종(32℃, 1일), 간이출하(30℃, 3일) 과정을 거쳐 부직포 육묘(12일 정도)를 실시하였다. 5월20일(이앙520)부터 5월30일(이앙530), 6월9일(이앙609)까지 10일 간격으로 드문모심기 전용 이앙기로 이앙하였으며, 주당 본수는 5.7개 정도였다. 이앙 시기별로 시험포장을 구분하였고 포장내에 2품종, 각각 3.3m2당 80주, 60주, 50주, 37주 등 재식밀도 처리구를 두었으며, 처리구마다 3반복 조사구(10주/반복, 5본/주) 설치하였다. 10a당 9-4.5-5.7kg(N-P₂O₅-K₂O)를 밑거름(50%)-분얼거름(20)-이삭거름(30) 등 3회 거쳐 시비하였다. 중간물떼기는 이앙32일째부터 10일간 실시하였으며, 예상 출수 30일 전에 충분하게 담수하였다. 이앙20일째부터 10일 간격으로 경수, 초장, 엽색도 등 생육 조사, 그리고 출수기, 후기 생육 및 병해충을 조사하였다. 향후 수확기에 수량, 수량구성요소, 미질 및 품위를 분석할 계획이다. 시험토양은 pH 6.0~6.3, EC는0.68~0.85dS/m, 유기물함량은 52~57g/kg 수준으로 높았다. 동진찰 발아율(94.0~98.1%)이 다복찰(89.9~94.9%)보다 우수하였다(3~6%P ↑). 다복찰 묘 충실도(102~106mg/주)가 동진찰(79~101mg/주)보다 다소 좋았으며, 이앙530 묘소질이 가장 좋았다. 동진찰 초장은 다복찰에 비해 다소 길었으나 이앙시기 및 재식밀도별 초장의 변화 유형은 비슷하였다. 이앙520구의 80주에서 초장이 가장 작았고 이앙609구에서는 80주에서 다소 길었으나, 처리구간의 유의성은 없었다. 동진찰 및 다복찰 경수는 37주에서 이앙 후 40일째, 50주, 60주, 80주에서는 30일째 가장 컸다. 출수기는 다복찰에 비해 동진찰이 3~7일 정도 빨랐으며, 특히 이앙520 동진찰에서는 재식밀도가 높을수록 출수기가 빠른 경향을 보였으며, 이앙530 이후에는 재식밀도간 차이가 거의 없었다. 동진찰에 비해 다복찰 간장이 3~6cm 작았으며, 2품종 모두 이앙609구에서 가장 낮은 값을 보였다. 수장도 간장과 비슷한 경향을 보였다. 수수는 2품종 모두 이앙이 늦을수록 증가하였으며, 37주에서 가장 높았으며, 80주에 비해 다복찰, 동진찰 각각 73.8%, 77.4% 높았다. 다복찰의 경우 3.3m²당 수수는 이앙시기별과 관계없이 상대적으로 80주에서 가장 많았고 이앙520에서 재식밀도간 차이는 감소하였지만 이앙시기가 늦을수록 수수는 증가하는 경향을 보였다. 동진찰도 비슷한 경향을 보였으며, 이앙520과 이앙609 사이에 수수 차이는 적었다. 병 발생은 잎집무늬마름병, 세균성벼알마름병, 이삭누룩병이 주로 관찰되었으며, 세균성 벼알마름병은 출수기와 맞물린 이앙530에서 가장 크게 발생하였으며, 이앙520도 비슷한 경향을 보였다. 이삭누룩병 발생이 심하였는데 재식밀도간 차이보다는 이앙시기별 차이가 더 크게 발생하였으며 품종 간의 병 발생 차이는 없었다. 이상의 결과로 수수 측면에서 조기 이앙할 경우에는 50~60주, 늦은 이앙 시에는 80주가 유리할 것으로 보이며, 추후주당 립수, 등숙률, 천립중 등을 조사하고 경영비 등을 고려하여 합리적인 이앙시기 및 재식밀도를 판단할 수 있을 것으로 판단된다.

• Journal of the Korean Institute of Gas
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• v.27 no.3
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• pp.19-26
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• 2023

Hydrogen, a clean energy source free of COx emissions, is poised to replace fossil fuels, with its usage on the rise. Despite its high energy content per unit mass, hydrogen faces limitations in storage and transportation due to its low storage density and challenges in long-term storage. In contrast, ammonia offers a high storage capacity per unit volume and is relatively easy to liquefy, making it an attractive option for storing and transporting large volumes of hydrogen. While NH₃ decomposition is an endothermic reaction, achieving excellent low-temperature catalytic activity is essential for process efficiency and cost-effectiveness. The study examined the effects of different zeolite types (5A, NaY, ZSM5) on NH₃ decomposition activity, considering differences in pore structure, cations, and Si/Al-ratio. Notably, the 5A zeolite facilitated the high dispersion of Ni across the surface, inside pores, and within the structure. Its low Si/Al ratio contributed to abundant acidity, enhancing ammonia adsorption. Additionally, the presence of Na and Ca cations in the support created medium basic sites that improved N₂ desorption rates. As a result, among the prepared catalysts, the 15 wt%Ni/5A catalyst exhibited the highest NH₃ conversion and a high H₂ formation rate of 23.5 mmol/g_cat·min (30,000 mL/g_cat·h, 600 ℃). This performance was attributed to the strong metal-support interaction and the enhancement of N₂ desorption rates through the presence of medium basic sites.

• Journal of Life Science
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• v.33 no.11
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• pp.915-922
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• 2023

Lactic acid bacteria (LAB) are widespread in a variety of environments including fermented dairy products, gastroinstetinal and urogenital tracts of human and animals, plant, soil and water. Leuconostoc mesenteroides DB3 was detected by the strongest antibacterial activities among 24 Leuconostoc strains isolated from Camellia japonica flowers. Acid tolerance of L. mesenteroides DB3 existed up to pH 2.5, but the resistance did not show at pH 2.0, which relatively excellent acid resistance existed. Bile acid tolerance was very stable within the test range to 1.2%. L. mesenteroides DB3 exhibited the optimal growth at 30℃, and showed a slight slow growth when compared with L. mesenteroides KCTC3505, which reached a stationary phase at 18 hr. The pH was changed along with the growth curve, but was maintained above pH 3.98. L. mesenteroides DB3 had higher initial antibacterial activities when compared to L. mesenteroides KCTC3505, but it showed similar activities with the standard strain after the latter part of the logarithmic growth phase. Although lactic acid production in L. mesenteroides DB3 was induced by lower amount in the initial part to the standard strain, it was exhibited by similar amounts after the late logarithmic growth phase. Muicin adhesion of L. mesenteroides DB-3 maintained superior to L. mesenteroides KCTC3505. Both strains showed excellent emulsification ability for kerosene. In summary, we evaluate that L. mesenteroides DB-3 has a high potential for application as probiotics owing to its excellent antibacterial activity, acid resistance, bile acid resistance, and muicin adhesion.

• Korean Journal of Remote Sensing
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• v.39 no.6_1
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• pp.1413-1425
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• 2023

The increasing frequency of wildfires due to climate change is causing extreme loss of life and property. They cause loss of vegetation and affect ecosystem changes depending on their intensity and occurrence. Ecosystem changes, in turn, affect wildfire occurrence, causing secondary damage. Thus, accurate estimation of the areas affected by wildfires is fundamental. Satellite remote sensing is used for forest fire detection because it can rapidly acquire topographic and meteorological information about the affected area after forest fires. In addition, deep learning algorithms such as convolutional neural networks (CNN) and transformer models show high performance for more accurate monitoring of fire-burnt regions. To date, the application of deep learning models has been limited, and there is a scarcity of reports providing quantitative performance evaluations for practical field utilization. Hence, this study emphasizes a comparative analysis, exploring performance enhancements achieved through both model selection and data design. This study examined deep learning models for detecting wildfire-damaged areas using Landsat 8 satellite images in California. Also, we conducted a comprehensive comparison and analysis of the detection performance of multiple models, such as U-Net and High-Resolution Network-Object Contextual Representation (HRNet-OCR). Wildfire-related spectral indices such as normalized difference vegetation index (NDVI) and normalized burn ratio (NBR) were used as input channels for the deep learning models to reflect the degree of vegetation cover and surface moisture content. As a result, the mean intersection over union (mIoU) was 0.831 for U-Net and 0.848 for HRNet-OCR, showing high segmentation performance. The inclusion of spectral indices alongside the base wavelength bands resulted in increased metric values for all combinations, affirming that the augmentation of input data with spectral indices contributes to the refinement of pixels. This study can be applied to other satellite images to build a recovery strategy for fire-burnt areas.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.68 no.3
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• pp.188-196
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• 2023

Wheat (Triticum aestivum L.) is an important crop in Korea, with a per capita consumption of 31.6 kg in 2019. In the southern region, wheat is grown after paddy rice, and it is harvested during the rainy season in mid-June. This timing, in combination with high humidity and untimely rainfall, activates the enzyme alpha-amylase, which breaks down starch in the wheat grains. As a result, sprouted grains have lower quality and value for flour. However, seeds that absorb water before sprouting are expected to maintain better quality. The aim of the study was to identify the critical period during wheat maturation when rainfall has the greatest impact on grain quality, to prevent price declines due to quality deterioration. Two wheat cultivars, Jokyoung and Hwanggeumal, were grown in a speed breeding room, and artificial rainfall was applied at different times after heading (30, 35, 40, 45, 50, and 55 days). The proportion of vitreous grains decreased from 40 to 55 days after heading (DAH). Both cultivars had chalky grain sections from 35 DAH, with Hwanggeumal having a higher proportion of vitreous grains. Starch degradation was observed using FE-SEM (Field Emission Scanning Electron Microscope) at 40 DAH for Jokyoung and 50 DAH for Hwanggeumal. Color measurements indicated increased L and E values from 40 DAH, with rain treatment at 55 DAH leading to a significant increase in L values for both cultivars. Ash content increased at 45 DAH, whereas SDSS decreased at 35 DAH. Overall, grain quality from 40 DAH until harvest was found to be affected to the greatest extent by direct exposure of the spikes to moisture. Red wheat showed better quality than white wheat. These findings have implications for the cultivation of high-quality wheat and can guide future research efforts in this area.

• Journal of Life Science
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• v.33 no.12
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• pp.1002-1014
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• 2023

The root of Cirsium japonicum var. maackii (Maxim.) has long been used in traditional medicine to prevent the onset and progression of various diseases and has been reported to exert a wide range of physiological effects, including antioxidant activity. However, research on its effects on hepatocytes remains scarce. This study used the human hepatocellular carcinoma HepG2 cell line to investigate the antioxidant activity of ethanol extract of C. japonicum root (EECJ) on hepatocytes. Hydrogen peroxide (H₂O₂) was used to mimic oxidative stress. The results showed that EECJ significantly reverted the decrease in cell viability and suppressed the release of lactate dehydrogenase in HepG2 cells treated with H₂O₂. Moreover, an analysis of changes in cell morphology, flow cytometry, and microtubule-associated protein light chain 3 (LC3) expression showed that EECJ significantly inhibited HepG2 cell autophagy induced by H₂O₂. Furthermore, it attenuated H₂O₂-induced apoptosis and cell cycle disruption by blocking intracellular reactive oxygen species and mitochondrial superoxide production, indicating strong antioxidant activity. EECJ also restored the decreased levels of intracellular glutathione (GSH) and enhanced the expression and activity of superoxide dismutase and GSH peroxidase in H₂O₂-treated HepG2 cells. Although an analysis of the components contained in EECJ and in vivo validation using animal models are needed, these findings indicate that EECJ is a promising candidate for the prevention and treatment of oxidative stress-induced liver cell damage.

• Korean Journal of Organic Agriculture
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• v.31 no.4
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• pp.453-460
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• 2023

This study was conducted to confirm the growth performance of Hanwoo steers according to the crude protein and calcium levels and their effects on carcass characteristics. The experiment consisted of a total of 4 groups: HPHC (CP 15%, Ca 1.2%), HPLC (CP 15%, Ca 0.6%), LPHC (CP 12.5%, Ca 1.2%), LPLC (CP 12.5%, Ca 0.6%). In the feeding trial, Hanwoo steers (650.8±16.27 kg, n = 32, 24 months of age) were divided into four feeding groups (n = 8 each) with the same initial body weight. Animals were fed with each rice straw and concentrate (1:9) until the late fattening stage. Growth performance was measured by daily weight gain, feed conversion rate, and final weight. Carcass characteristics were measured carcass weight, loin area, back-fat thickness and marbling score. There was no significant difference in growth performance and carcass characteristics among the treatment groups. However, the ratio of meat quality grade 1⁺ or higher was 76% in LPLC, which was higher than other treatments (HPHC, 63%; HPLC, 63% and LPHC, 50%). Therefore, reducing crude protein in the feed did not affect growth and carcass characteristics. In addition, calcium control in the late fattening stage did not affect growth performance. In LPLC, the ratio of meat quality 1⁺ or higher was the highest, so additional research on calcium control in feed is thought to be necessary. However, there was no significant difference in the relationship between protein and calcium levels in feed in all study results, so the influence of the two factors on each other is thought to be low.

• Conservation Science in Museum
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• v.30
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• pp.71-88
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• 2023

This paper examined the visible characteristics and chemical composition of glass beads from the Joseon Dynasty as well as the associations thereof. It also explored the characteristics and uses of glass beads by region. This study covered a total of 1,819 pieces excavated from 25 locations in the Gyeonggi, Chungcheong, and Gyeongsang regions, of which 537 pieces were analyzed for their chemical composition. Glass beads of the Joseon Dynasty take a variety of shapes such as a Round, Coil, Floral, Segmented, Flat, Oval, and Calabash. Colors vary from shades of brown (brown, lemon yellow) and shades of blue (Bluish-Green, greenish-Blue, Purple-Blue) to shades of white (colorless, white) and shades of green (Green, Greenish-Blue, Greenish-Brown). Brown accounts for the largest percentage, followed by Bluish-Green, greenish-Blue. It was identified that Drawing technique was the most common glass bead production technique of the Joseon Dynasty. Potassium oxide (K₂O) was the most common flux agent for glass beads, while the potash glass and mixed alkali glass groups account for the largest quantity. The choice of stabilizers depended on the type of flux agents used, but the most common were calcium oxide (CaO) and aluminum oxide (Al₂O₃). The potash glass and potash lead glass groups are high in CaO and low in Al₂O₃, the mixed alkali glass group is high in CaO, and the lead glass group is low in CaO. In terms of the association between color and shape, most of the beads with shade of brown and blue have round shapes of brown and blue have spherical shapes, while the coil shape is prominent in blue beads. A high percentage of green and colorless beads also take the shape of a coil, while white beads in general have a floral shape. In terms of the association between shape and chemical composition, round, floral and segmented shapes account for a high percentage of the potash glass group, while coil and flat shapes are common in the mixed alkali glass group. This paper also analyzed the colorants for each color based on the association between color and chemical composition. Iron (Fe) was used as the colorant for brown and white, and titanium (Ti) and iron were used for light yellow. Purple-Blue was produced by by cobalt (Co), and greenish-Blue, Bluish-Green, green, Greenish-Blue were produced by iron and copper (Cu). Colorless beads had a generally low colorant content.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.3
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• pp.168-177
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• 2008

Trafficablility of a miner and potential environmental impacts due to mining activities should be considered in the selection of a commercial manganese nodule mining site. These two factors can be evaluated comparatively with physical properties and shear strength of sea-bed sediments. For the qualitative comparison of potential minig sites in terms of these two factors, physical properties such as water contents, void ratios, porosities, and grain densities, and shear strengths of surface sediments were determined for the three potential manganese nodule mining sites(KR1, KR2, and KR5) in the Korean manganese nodule contract area, northeast Pacific. For the study, sediment samples were collected from 107 stations from 2004 to 2006. The physical properties of surface sediments showed more significant differences between northern(KR1, KR2) and southern(KR5) blocks than between northern blocks(KR1 vs. KR2). Water content, void ratio, and porosity of sediments from KR5 were relatively higher than those from KR1 and KR2. Grain density of sediments from KR5 was relatively lower than those from KR1 and KR2. Shear strengths of the top 10cm sediments were higher in KR1 and KR2, whereas those of the deeper part were highest in KR5 block. Generally, sediments of high water contents are less suspendible than those of the low water contents by benthic disturbances, thus less disturbance is expected in the sediments of high water content by mining activities. In terms of trafficability, the shear strength of sediment below 10 cm deep is more important than shallower part because miner will disturb at least top 10 cm interval of the surface sediments. Base on these results, we conclude that KR5 area will be the best site for commercial mining among three investigated sites in this study.

• Food Science and Preservation
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• v.30 no.2
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• pp.347-357
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• 2023

The succulent plant Aeonium sedifolium leaves contain several compounds that are of interest for their cosmetic uses on the skin. This study measured the inhibitory effects of enzyme production and antioxidant, astringent effects and skin wrinkles using Aeonium sedifolium leaves (ASL). The total phenolics compounds (TPC) content of ASL under optimal extraction conditions was 34.49 mg/g for hot water extract (ASLW) and 61.64 mg/g for 50% ethanol extract (ASLE). The ASLW and ASLE extracts were freeze-dried, powdered, and used as solids. TPC content, 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity, and 2,2'-azinobis (3-ethylben-zothiazoline 6-sulfonate) (ABTS) radical inhibition of the ASL phenolics were tested. The DPPH radical scavenging activities of ASLW and ASLE were tested at a TPC of 100 ㎍/mL. ABTS radical inhibition showed antioxidant activity of 100.00% in ASLW and ASLE, and the antioxidant protection factor of ASLW and ASLE was 1.07 and 1.22, respectively. The thiobarbituric acid-reactive substance (TBARS) inhibitory activity of ASLW and ASLE was 77.00%. The elastase inhibitory activity of ASLE was 69.03%, and collagenase inhibition activity for ASLW and ASLE was 29.82% and 54.76%, respectively. The astringent effect of ASLE was 89.82% at a TPC of 200 ㎍/mL. Thus, we concluded that ASL has the potential as a functional cosmetic ingredient with anti-aging effects on the skin.