• Journal of the Korean Association of Geographic Information Studies
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• v.7 no.1
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• pp.62-74
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• 2004

Baekdu-daegan is the greatest mountain chain as well as the major ecological axis of the Korean Peninsula. In recent year, however, this area is faced with the various kinds of developmental urge. To cope adequately with these problems, this study was executed to prepare synthetic and systematic management with conservation-oriented strategy for Baekdu-daegan and to suggest spatially definite zoning for the managerial area. This study is to take into consideration the traditional concepts of stream and watershed as well as the actual disturbance on Baekdu-daegan area. The study area is selected with semi-mountainous type, from Namdeokyusan to Sosagogae. To propose the process for reasonably establishing the managerial boundary adjacent to the Ridges, the analysis was carried out that ArcGIS was mainly used for its analysis with digital maps, Landsat TM image and ArcGIS Hydro Model. Landsat TM image was classified by 5 land use types such as cultivated land, urban area, barren area, water body and forest. Based on these analyses results, the managerial boundaries as alternatives from the Ridges were produced by watershed expansion process, and used for tracing the changes of areal ratio of various land use types to the relevant watersheds to search out the adequate managerial boundary. The results show that watershed expansion process could be effective tool for establishing the managerial boundary, and eighth expanded watershed toward Muju-Gun(west) and fifth expanded watershed toward Geochang-Gun(east) might be included for the adequate managerial boundary of the case site.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.579-582
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• 2009

A new red leaf lettuce (Lactuca sativa L.) cultivar, "Mihong" which has late bolting and deep red leaf color was developed from a cross of "Danhongongchukmyeon" (deep red but early bolting and low yield) and "Hajicheongchukmyeon" (late bolting and high yield). The selection and breeding of advanced lines were done by pedigree method during 2000-2006. The advanced lines were evaluated for yield and adaptability in Korea (Gangwon, Kyunggi, Chungbuk, Kyungnam, Jeonnam, Jeonbuk, and Jeju) from 2007 to 2008. The "Mihong" has gray seed color, traverse elliptic leaves and deep red color. Compared to "Dukseomjeokchukmyeon", marketable yield of "Mihong" was higher by 2% (at 291 g per plant) as a 17.3 ton/ha, but with particularly improved good expression of deep red leaf color in high temperature cultivation in the field. The shelf-life of "Mihong" was three weeks longer than "Dukseomjeokchukmyeon" at $4^{\circ}C$. The amount of anthocyanin content of "Mihong" were higher than with "Dukseomjeokchukmyeon" at 28.9 mg/100 g. Especially the degree of leaf hardness in "Mihong" showed $26.9kg/cm^2$ compared to "Dukseomjeokchukmyeon". therefore, its taste is better, more crispy, and sweeter than "Dukseomjeokchukmyeon" This new cultivar "Mihong" can be cultivated in all year around even if summer time cultivation.

• Korean Journal of Medicinal Crop Science
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• v.26 no.6
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• pp.477-481
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• 2018

Background: Recently, jujube (Zizyphus jujuba Mill.) has been attracting attention as a fruit, and its cultivation in rain shelter house is increasing to produce the high quality fresh jujube. This study was carried out to investigate the growth and fruit characteristics of jujube according to the types of rain shelter house. Methods and Results: The characteristics of 5-year-old Bokjo cultivar cultivated in 3 types of rain shelter house, multi span rain shelter house with roof vent (Type I), single span house with a column in the center and roof vent (Type II) and single span house with a column in the center and without roof vent (Type III), and open field were examined. The sprouting and blooming period were different among the types of rain shelter house. The diameter of main stem was higher in rain shelter houses than in the open field. There was no a significant difference in fruit number per leaf stem among the types of cultivation. The incidence of fruit cracking in open field cultivation which was 51.2% was much higher than that in Type I 21.6%, Type II 19.3%, and Type III 25.5%. The fruit size and weight in rain shelter houses, especially in Type III rain shelter house were higher than those in the open field and the soluble solids content of fruit in Type I and Type II was higher than in Type III rain shelter house and the open field. Conclusions: The results show that the growth and fruit quality of jujube were improved by cultivation in rain shelter house, and affected by the types of rain shelter house.

• Journal of Life Science
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• v.29 no.2
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• pp.164-172
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• 2019

In Korea, shiitake mushroom, Lentinula edodes, is cultivated on artificial medium containing oak sawdust and wheat bran. The annual production of spent mushroom substrate (SMS) of shiitake, a byproduct of the mushroom industry, is estimated to reach over 50,000 tons per year. This study aimed to improve the use of SMS as a novel bioresource. Hot water extracts of SMS after the first and third harvest were prepared and their bioactivities evaluated. Hot water extracts of uninoculated medium and shiitake were used as controls. Extracts of SMS showed higher radical scavenging of DPPH anions, ABTS cations, nitrites, and a higher reducing power than those of shiitake or medium extracts. After the first and third harvests at 0.5 mg/disc, SMS extracts showed no antibacterial or antifungal activities against the pathogenic and food-spoilage bacteria and fungi. However, they showed good inhibitory activities against ${\alpha}$-glucosidase at 0.5 mg/ml. In addition, SMS extracts had strong anti-coagulation activities via their inhibition of thrombin, prothrombin, and blood coagulation factors without platelet aggregation activity. Our results suggested SMS should no longer be perceived as a useless byproduct but should be understood as a novel bioresource, the extracts of which could be developed as antioxidant, antidiabetic, and antithrombosis agents.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.3
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• pp.189-197
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• 2022

This study investigated the antioxidant and yield properties of eight adzuki bean (Vigna angularis L.) cultivars grown under different mean temperatures and sunshine hours in 2020 and 2021. Compared to 2021, which had a normal mean temperature, 2020 showed a lower mean temperature during the pod-extension and grain-filling periods. In addition, due to frequent rainfall during the vegetative period in 2020, there were fewer hours of sunshine in 2020 than in 2021. The adzuki bean yield was approximately 13% lower in 2020 than in 2021 due to the decreased number of pods per plant and 100-seeds weight. 'Hongda' and 'Hongjin' cultivars showed more stable yields than the 'Arari' variety, which is the most commonly cultivated variety in Korea. Moreover, the 'Hongda' and 'Hongjin' cultivars had higher yields than the 'Arari' variety in both years. Compared to 2021, in 2020, when the weather conditions were unfavorable, both antioxidant levels and activity were higher. 'Hongda' had higher antioxidant levels and activity than the other cultivars over the 2 years. These results suggest that the antioxidant levels and activity were good in 2020, with an approximately 13% decrease in yield compared to 2021, which was a normal year with respect to mean temperature and sunshine hours.

• Journal of Bio-Environment Control
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• v.32 no.1
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• pp.15-22
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• 2023

Roses are one of the most produced flower species in the world, and cut roses are produced in the greenhouses all year round. Recently, due to the increase in the temperature in the greenhouses in summer, the quality of cut roses is seriously deteriorated, such as shortening the stem length. This study was conducted to investigate the effects of the growing seasons on the qualities of cut roses and also to test the effect of cooling at night in high temperature season on the cut flower qualities of roses. Comparing the qualities and yields of cut roses for each season, the major cut flower qualities such as flower stem length, stem diameter and fresh weight were statistically significantly decreased in roses ('Pink Beauty' and 'Pink Shine') produced in summer. The yields didn't show a statistically significant difference in both cultivars. Investigating the cut flower qualities, the flower stem length increased by 15% for 'Pink Beauty', 11% for 'Ararat', and 12% for 'Pink Shine' when treated with cooling at night in warm season than the untreated control. In addition, when treated with cooling at night in warm season, the fresh weight of all three cultivars increased by 20-30% statistically significantly than conventionally cultivated control. It is expected that cooling at night in warm season will be helpful to improve the cut flower quality deterioration in summer.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.439-446
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• 2022

Soybean is a crop with high-quality of protein and oil, and it is one of the most widely used genetically modified (GM) crops in the world today. In South Korea, Kwangan is the most utilized variety as a parental line for GM soybean development. In this study, untargeted LC-MS metabolomic approaches were used to compare metabolite profiles of Kwangan and three other commercial varieties cultivated in Gunwi and Jeonju in 2020 year. Metabolomic studies revealed that the 4 soybean varieties were distinct based on the partial least squares-discriminant analysis (PLS-DA) score plots; 18 metabolites contributed to variety distinction, including phenylalanine, isoflavones, and fatty acids. All varieties were clearly differentiated by location on the PLS-DA score plot, indicating that the growing environment is also attributable to metabolite variability. In particular, isoflavones and linolenic acid levels in Kwangan were significantly lower and higher, respectively compared to those of the three varieties. It was discussed that it might need to include more diverse conventional varieties as comparators in regard to metabolic characteristics of Kwangan for the assessment of substantial equivalence biogenetically engineered soybeans in a Kwangan-variety background.

• Proceedings of the Korea Water Resources Association Conference
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• 2023.05a
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• pp.30-30
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• 2023

This study aims to establish the multi-reservoir operation system model in the Upper Mun River Basin which includes 5 main dams namely, Mun Bon (MB), Lamchae (LC), Lam Takhong (LTK), Lam Phraphoeng (LPP), and Lower Lam Chiengkrai (LLCK) Dams. The knowledge and AI technology were applied aiming to develop innovative prototype for SMART dam-reservoir operation in future. Two different sorts of reservoir operation system model namely, Fuzzy Logic (FL) and Constraint Programming (CP) as well as the development of rainfall and reservoir inflow prediction models using Machine Learning (ML) technique were made to help specify the right amount of daily reservoir releases for the Royal Irrigation Department (RID). The model could also provide the essential information particularly for the Office of National Water Resource of Thailand (ONWR) to determine the short-term and long-term water resource management plan and strengthen water security against flood and drought in this region. The simulated results of base case scenario for reservoir operation in the Upper Mun from 2008 to 2021 indicated that in the same circumstances, FL and CP models could specify the new release schemes to increase the reservoir water storages at the beginning of dry season of approximately 125.25 and 142.20 MCM per year. This means that supplying the agricultural water to farmers in dry season could be well managed. In other words, water scarcity problem could substantially be moderated at some extent in case of incapability to control the expansion of cultivated area size properly. Moreover, using AI technology to determine the new reservoir release schemes plays important role in reducing the actual volume of water shortfall in the basin although the drought situation at LTK and LLCK Dams were still existed in some periods of time. Meanwhile, considering the predicted inflow and hydrologic factors downstream of 5 main dams by FL model and minimizing the flood volume by CP model could ensure that flood risk was considerably minimized as a result of new release schemes.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.78-78
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• 2022

Food productivity in North Korea is about 50% lower than in South Korea. In order to increase the productivity of major crops, it is necessary to develop early maturing, disease resistance, and high-yielding varieties and apply them early. Since the late 1990s, North Korea has been actively developing potatoes, rice and com as major food crops, and soybeans are considered important as a protein-supplying crop. Domestic cultivated varieties, which are expected to be most adaptable eco-climatologically, are mainly selected from soil with high nutrient soil. It is necessary to test separately for adaptability in low organic soil. So it is very necessary to apply technology to improve soil improvement through rotational crop selection in the middle and long-term. Therefore, this study was conducted to test the adaptability to low organic soils of domestic cultivars and to select varieties. In 2021 there are twenty two (22) varieties of soybeans were grown in low organic soil at the field of Chungbuk National University. This year twenty two (22) varieties of soybeans were also grown in low organic soil at the field of Chungbuk National University. Sowing was done on June 10, the planting distance was 70cm × 15cm, after opening the cotyledons fully, the soybeans were thinned and leaving two plants per hole. In addition, various types of growth characteristics and quantitative components were investigated to evaluate the adaptability to low organic soil of domestic varieties. This study was conducted to investigate the growth characteristics and quantitative components of soybean varieties grown in low organic soil. The flowering period of 22 varieties of soybeans was about 14 days from July 22 to August 4. The flowers of the beans were white, purple, light purple and the pubescence color was gray and brown where most of them were gray. The highest plant height was up to 130.4 cm and lowest was 20.3 cm, highest stem length was up to 119.5 cm and lowest was 15.3 cm. Highest first pod height (FPH) was up to 34.0 cm and lowest was 3.0 cm. Highest stem diameter was up to 15.76mm and lowest was 1.76 mm. Number of main stem nodes was up to 19 and at least 1. Number of branch was up to 10 and at least 0. The number of pod per plant was up to 121. Bacterial pustule has been spread in soybean field.

• Korean Journal of Agricultural and Forest Meteorology
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• v.25 no.4
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• pp.245-257
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• 2023

The representative crop in the Republic of Korea, rice, is cultivated over extensive areas every year, which resulting in reduced resistance to pests and diseases. One of the major rice diseases, rice blast disease, can lead to a significant decrease in yields when it occurs on a large scale, necessitating early detection and effective control of rice blast disease. Drone-based crop monitoring techniques are valuable for detecting abnormal growth, but frequent image capture for potential rice blast disease occurrences can consume significant labor and resources. The purpose of this study is to early detect rice blast disease using remote sensing data, such as drone and satellite images, along with weather data. Satellite images was helpful in identifying rice cultivation fields. Effective detection of paddy fields was achieved by utilizing vegetation and water indices. Subsequently, air temperature, relative humidity, and number of rainy days were used to calculate the risk of rice blast disease occurrence. An increase in the risk of disease occurrence implies a higher likelihood of disease development, and drone measurements perform at this time. Spectral reflectance changes in the red and near-infrared wavelength regions were observed at the locations where rice blast disease occurred. Clusters with low vegetation index values were observed at locations where rice blast disease occurred, and the time series data for drone images allowed for tracking the spread of the disease from these points. Finally, drone images captured before harvesting was used to generate spatial information on the incidence of rice blast disease in each field.