• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.246-254
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• 2022

Domestic facility agriculture grows rapidly, such as modernization and large-scale. And the production scale increases significantly compared to the area, accounting for about 60% of the total agricultural production. Greenhouses require energy input to create an appropriate environment for stable mass production throughout the year, but the energy load per unit area is large because of low insulation properties. Through the rooftop greenhouse, one of the types of urban agriculture, energy that is not discarded or utilized in the building can be used in the rooftop greenhouse. And the cooling and heating load of the building can be reduced through optimal greenhouse operation. Dynamic energy analysis for various environmental conditions should be preceded for efficient operation of rooftop greenhouses, and about 40% of the solar energy introduced in the greenhouse is energy exchange for crops, so it should be considered essential. A major analysis is needed for each sensible heat and latent heat load by leaf surface temperature and evapotranspiration, dominant in energy flow. Therefore, an experiment was conducted in a rooftop greenhouse located at the Korea Institute of Machinery and Materials to analyze the energy exchange according to the growth stage of crops. A micro-meteorological and nutrient solution environment and growth survey were conducted around the crops. Finally, a regression model of leaf temperature and evapotranspiration according to the growth stage of leafy vegetables was developed, and using this, the dynamic energy model of the rooftop greenhouse considering heat transfer between crops and the surrounding air can be analyzed.

• Journal of Wetlands Research
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• v.24 no.3
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• pp.204-212
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• 2022

The LID technique began to be applied in Korea after 2009, and LID facilities are installed and operated for rainwater management in business districts such as the Ministry of Environment, the Ministry of Land, Infrastructure and Transport, and LH Corporation, public institutions, commercial land, housing, parks, and schools. However, looking at domestic cases, the application cases and operation periods are insufficient compared to those outside the country, so appropriate design standards and measures for operation and maintenance are insufficient. In particular, LID facilities constructed using LID techniques need to maintain the environment inside LID facilities because hydrological and environmental effects are expressed by material circulation and energy flow. The LID facility is designed with the treatment capacity planned for the water circulation target, and the proper maintenance, vegetation, and soil conditions are periodically identified, and the efficiency is maintained as much as possible. In other words, the soil created in LID is a very important design element because LID facilities are expected to have effects such as water pollution reduction, flood reduction, water resource acquisition, and temperature reduction while increasing water storage and penetration capacity through water circulation construction. In order to maintain and manage the functions of LID facilities accurately, the current state of the facilities and the cycle of replacement and maintenance should be accurately known through various quantitative data such as soil contamination, snow removal effects, and vegetation criteria. This study was conducted to investigate the current status of LID facilities installed in Korea from 2009 to 2020, and analyze soil changes through the continuity and current status of LID facilities applied over the past 10 years after collecting soil samples from the soil layer. Through analysis of Saturn, organic matter, hardness, water contents, pH, electrical conductivity, and salt, some vegetation-type LID facilities more than 5 to 7 years after construction showed results corresponding to the lower grade of landscape design. Facilities below the lower level can be recognized as a point of time when maintenance is necessary in a state that may cause problems in soil permeability and vegetation growth. Accordingly, it was found that LID facilities should be managed through soil replacement and replacement.

• Economic and Environmental Geology
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• v.55 no.5
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• pp.551-561
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• 2022

Geophysical exploration methods are very useful for generating high-resolution images of underground structures, and such methods can be applied to investigation of buried cultural properties and for determining their exact locations. In this study, image feature extraction and image segmentation methods were applied to automatically distinguish the structures of buried relics from the high-resolution ground-penetrating radar (GPR) images obtained at the center of Silla Kingdom, Gyeongju, South Korea. The major purpose for image feature extraction analyses is identifying the circular features from building remains and the linear features from ancient roads and fences. Feature extraction is implemented by applying the Canny edge detection and Hough transform algorithms. We applied the Hough transforms to the edge image resulted from the Canny algorithm in order to determine the locations the target features. However, the Hough transform requires different parameter settings for each survey sector. As for image segmentation, we applied the connected element labeling algorithm and object-based image analysis using Orfeo Toolbox (OTB) in QGIS. The connected components labeled image shows the signals associated with the target buried relics are effectively connected and labeled. However, we often find multiple labels are assigned to a single structure on the given GPR data. Object-based image analysis was conducted by using a Large-Scale Mean-Shift (LSMS) image segmentation. In this analysis, a vector layer containing pixel values for each segmented polygon was estimated first and then used to build a train-validation dataset by assigning the polygons to one class associated with the buried relics and another class for the background field. With the Random Forest Classifier, we find that the polygons on the LSMS image segmentation layer can be successfully classified into the polygons of the buried relics and those of the background. Thus, we propose that these automatic classification methods applied to the GPR images of buried cultural heritage in this study can be useful to obtain consistent analyses results for planning excavation processes.

• Korean Journal of Ecology and Environment
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• v.55 no.2
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• pp.132-144
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• 2022

The fish community in the Seomjin River-Seomjin River Estuary-Gwangyang Bay coast continuum was investigated three times from March 2019 to October 2019. The collected species at the eight sites during the survey period were 49 species belonging to 31 families, including two endangered species. According to Bray-Curtis similarities, observations were divided into four groups based on the fish community composition; two groups (group 1, 2) and two uncategorized groups (group 3, 4). ANOSIM based on spatial and temporal groupings indicated that the spatial differences in fish communities (R=0.398, P=0.001) were relatively more important than the temporal differences (analysis of similarities, R=0.273, P=0.002). In particular, there were significant differences between groups 1 and 2 (analysis of similarities, R=0.556, P=0.001), and similarity percentage analysis revealed that Argyrosomus argentatus (9.4%), Favonigobius gymnauchen (6.9%) and Konosirus punctatus (5.9%) contributed to these differences of fish assemblages for each group. The fish fauna distributed in the Seomjin River-Gwangyang Bay ecosystem were spatially divided and the number of species and number of individuals showed seasonal differences. This study could be a basis for understanding changes in the fish community and implementing conservation and management strategies on major species within a continuous environment of the river-estuary-ocean continuum.

• 한국체육학회지인문사회과학편
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• v.51 no.6
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• pp.515-522
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• 2012

The purpose of this study was to investigate the total energy expenditure (TEE) and then it's relationship between degree of energy expenditure and physical characteristics of Korean 1,370 children. The values of total energy expenditure were classified into under 1,000kcal/week, 1.000~2,000kcal/week, and over 2,000kcal/week. The average TEE of boys and girls were 2,088.4kcal/week and 1,695.6kcal/week. When compared with children of under 1,000kcal/week, the boys of the 1,000~2,000kcal/week showed significant difference in height (p<.001), weight (p<.05), waist circumference (p<.05), blood pressure (p<.001) and girls showed in height (p<.05), blood pressure (p<.01), heart rate (p<.01). However, the boys of over 2,000kcal/week showed significant difference in height, weight, waist circumference, BMJ, and blood pressure (p<.001) and girls in height (p<.001), waist circumference (p<.001), BMI (p<.05), blood pressure (p<.001). For correlation between the TEE and physical characteristics, TEE had significantly correlations with height (r=.298, p<.001), body weight (r=-.331, p<.001), waist circumference (r=-.236, p<.001), BMI (r=-.252, p<.001), blood pressure (r=-.239, p<.001), and heart rate (r=-.226, p<.001) for boys and height (r=.236, p<.001), systolic blood pressure (r=-.310, p<.001), and diastolic blood pressure (r=-.180, p=.016) for girls. These results show that physical characteristics were affected by physical activity for boys while only height and blood pressure were affected in girls.

• Journal of Food Hygiene and Safety
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• v.38 no.2
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• pp.37-45
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• 2023

The surge in food delivery systems during the coronavirus 2019 pandemic necessitated this study of heavy metal migration from food contact materials (FCMs). A total of 104 samples of FCMs, comprising 51 polypropylene (PP), 21 polyethylene (PE), and 32 polystyrene (PS) samples of six different types of FCMs (containers, covers, table utensils, cups, pouches, and wrappers) used for food delivery distributed in Korea, were collected and investigated for migration of three heavy metals (Pb, Cd, and As) using inductively coupled plasma-mass spectrometry (ICP-MS) to determine whether they complied with Korea's Standards and Specifications for Utensils, Containers, and Packages. Acetic acid (4%, v/v) was used as the food simulant, and tests were performed at 100℃ (in harsh conditions) for 30 min. Linearity of Pb, Cd, and As showed acceptable results with a coefficient of determination (R²) value of 0.9999. Limit of detection (LOD) and limit of quantification (LOQ) of Pb, Cd, and As were 0.001, 0.001, and 0.001 ㎍/L and 0.002, 0.003, and 0.003 ㎍/L, respectively. Accuracy and precision results complied with the criteria presented in the European Commission Joint Research Centre guidelines. The average concentration of Pb, Cd, and As migration detected in a total of 104 samples was 0.009-0.260 ㎍/L, which was very low compared with the migration specification set in the Standards and Specifications for Utensils, Containers, and Packages. The maximum level of Pb corresponded to 0.23% of the migration limit. There were no samples exceeding the limit. Thus, this study confirmed that the heavy metal contents of FCMs used for delivery food distributed in Korea were safely managed. The data from this study represent an invaluable source for science-based safety management of hazardous heavy metals migrating from FCMs used in the food delivery industry.

• Korean Journal of Poultry Science
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• v.50 no.2
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• pp.91-99
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• 2023

This study aimed to develop a high-productivity breed of Korean native Samgye chicken. We evaluated the production performance of six Korean native chicken combinations (KNC-SCYC, SCYD, SDYC, SDYD, SYYC, SYYD) and GSP-Hanhyup Korean native chickens, with Baeksemi chickens used as a control group. The performance test was conducted from hatching to 7 weeks of age on 756 chickens, and we measured survival rate, body weight, shank length, feed utility, and carcass yield. The overall survival rate was nearly 100% for all strains. However, body weight showed significant differences between strains at all ages (P<0.01), with Baeksemi weighing 863.8±76.9 g, GSP-Hanhyup weighing 804.7±72.5 g, and KNC-combinations weighing 543.0±61.8 g at 5 weeks of age. The duration needed to reach 850 g was estimated to be 34.5 days for Baeksemi, 37.5 days for GSP-Hanhyup, and 45.8-48.8 days for KNC-combinations. Carcass yield percentage was highest for KNC-SYYD combination at 63.3%, followed by Baeksemi at 60.4%, and GSP-Hanhyup at 56.1%. Shank length at 850 g body weight was 7.6 cm for KNC-SYYD combination, 7.8 cm for Baeksemi, and 8.0 cm for GSP-Hanhyup. The feed conversion ratio at 850 g body weight was 1.81 for Baeksemi, 2.17 for GSP-Hanhyup, and 2.27 for KNC-SCYC combination. Our results suggest that the KNC-SYYD combination and GSP-Hanhyup breed have the potential to be used in Samgye production due to their moderate growth performance, higher carcass yield, and shorter shank length, despite their lower growth productivity and feed efficiency when compared to Baeksemi.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.398-403
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• 2023

Process-based K-cabbage model is based on physiological processes such as photosynthesis and phenology, making it possible to predict crop growth under different climate conditions that have never been experienced before. Current first-stage process-based models can be used to assess climate impact through yield prediction based on climate change scenarios, but no comparison has been performed between big data obtained from the main production area and model prediction so far. The aim of this study was to find out the direction of model improvement when using the current model for yield prediction. For this purpose, model performance evaluation was conducted based on data collected from farmers growing 'Chungwang' cabbage in Taebaek and Samcheok, the main producing areas of Chinese cabbage in highland region. The farms surveyed in this study had different cultivation methods in terms of planting date and soil water and nutrient management. The results showed that the potential biomass estimated using the K-cabbage model exceeded the observed values in all cases. Although predictions and observations at the time of harvest did not show a complete positive correlation due to limitations caused by the use of fresh weight in the model evaluation process (R²=0.74, RMSE=866.4), when fitting the model based on the values 2 weeks before harvest, the growth suitability index was different for each farm. These results are suggested to be due to differences in soil properties and management practices between farms. Therefore, to predict attainable yields taking into account differences in soil and management practices between farms, it is necessary to integrate dynamic soil nutrient and moisture modules into crop models, rather than using arbitrary growth suitability indices in current K-cabbage model.

• Journal of Marine Life Science
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• v.8 no.2
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• pp.166-177
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• 2023

The giant freshwater prawn (Macrobrachium rosenbergii) suffers economic losses in aquaculture facilities due to problems such as poor body color and carapace weakness. While this species is farmed on an animal-based diet, in the wild it consumes a detritus diet with a high proportion of plant matter. The plant matter they consume in the wild is not only a source of basic nutrients, but also carotenoids, which are responsible for body color. Korean goldenbell (Forsythia koreana) is a flowering tree widely distributed in Korea, and its leaves contain carotenoids comparable to yellow carrots. In this study, we investigated the effects of feeding Forsythia leaves to M. rosenbergii on their body color and health. The experimental diets were 100% commercial feed (control), CON, 80% commercial feed plus 20% Forsythia leaf powder, FP, and 80% commercial feed plus 20% unprocessed Forsythia leaves, FL, and each diet was fed to juvenile prawn with an average weight of 1.1 ± 0.2 g for 10 weeks. In terms of body color, the CON prawn were consistently clear ivory in color, while the FP and FL prawn changed from blue to dark brown as the days of rearing progressed. Survival and growth were not significantly different between CON and FP or FL. Histological comparison of the hepatopancreas revealed that the vacuole size of B cells, the constituent cells of the hepatopancreatic tubule, was significantly larger in FP and FL compared to CON. The vacuoles of B cells are responsible for the absorption and digestion of nutrients, suggesting that the supply of Forsythia leaves may have had a positive effect on the health of the M. rosenbergii. The above results show that the use of Forsythia leaves in the aquaculture of M. rosenbergii can be expected to improve body color and health without inhibiting growth.

• Journal of Life Science
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• v.33 no.10
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• pp.820-827
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• 2023

Since COVID-19 began at the end of 2019, the wearing time of protective clothing used to prevent pathogenic bacteria and virus infection has increased, and the development of safe protective materials that are human-friendly and have antibacterial and antiviral functions has been required. In this study, we investigated the possibility of developing natural antibacterial protection materials using ethanol extract of the medicinal plant Zanthoxylum Piperitum DC. The antibacterial activity assay of the 80% ethanol extract of Z. piperitum DC leaves against various nosocomial infectious bacteria, using the disk diffusion method, showed that Staphylococcus aureus ATCC 25923, Klebsiella pneumoniae ATCC 13883, Salmonella typhimurium, and Aeromonas hydrophila are sensitive to the inhibitory action of the extract. The IC₅₀ values of the ethanol extract against S. aureus, K. pneumoniae, P. vulgaris and A. hydrophila were about 0.59 mg/ml, 0.50 mg/ml, 1.06 mg/ml, and 0.06 mg/ml, respectively. To determine whether the ethanol extract of Z. piperitum DC leaves can be applied to the development of antibacterial protective fabric, the ethanol extract was tested using a protective fabric from the KM Health Care Corp. using the JIS L1902-Absorption method. As a result, the bacteriostatic and bactericidal activity values of S. aureus ATCC 25923 and K. pneumoniae ATCC 13883 appeared to be more than 2.0 when treated with the ethanol extract at a concentration of 1% (w/v). Together, these results suggest that Z. piperitum DC leaves can be applied to develop natural antibacterial functional protective fabrics.