• Korean Journal of Breeding Science
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• v.51 no.4
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• pp.496-503
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• 2019

The soybean cultivar, 'Saegeum', has been developed for preparing soy-paste and tofu. The soybean cultivars 'Daepung' and 'SS98207-3SSD-168' were crossed in 2003 to obtain 'Saegeum'. Single seed descent method was used to advance the generation from F₃ to F₅, and the plant lines with promising traits were selected from F₆ to F₇ by pedigree method. The preliminary yield (PYT) and advanced yield trials (AYT) were conducted from 2009 to 2010, and the regional yield trial (RYT) was conducted in 12 regions between 2011 and 2013. The morphological characteristics of 'Saegeum' were as follows: determinate plant type, white flower, tawny pubescence color, and brown pod color. Flowering and maturity dates were August 2, XXXX and October 17, XXXX, respectively. Plant height, first pod height, number of nodes, number of branches, and number of pods were 79 cm, 18 cm, 16, 2.3, and 44, respectively. The seed characteristics of 'Saegeum' were as follows: yellow spherical shape, yellow hilum, and the 100-seed weight was 25.4 g. 'Saegeum' was resistant to bacterial pustule and SMV in the field test, and its lodging resistance was mildly strong, whereas its shattering resistance was excellent. The ability of this cultivar to be processed into tofu, soybean malt, and other fermented products was comparable with that of 'Daewonkong'. The yield of 'Saegeum' in the adaptable regions was 3.02 ton ha^-1. Thus, 'Saegeum' is adaptable to mechanized harvesting because of its high first pod height, as well as lodging and shattering resistance. (Registration number: 5929)

• KOREAN JOURNAL OF CROP SCIENCE
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• v.56 no.4
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• pp.404-412
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• 2011

This experiment was conducted to clarify the effect of the temperature for grain filling duration on quality and taste of cooked rice cultivated in different region in Korea. In 2006 and 2007, 4 mid-late maturing group of rice varieties (Nampyeongbyeo, Ilpumbyeo, Junambyeo and Dongjin 1) were cultivated in 28 experimental plots of 27 different regions located in 8 provinces. The taste of cooked rice were positively correlated with 1,000 grain weight but negatively correlated with protein content of brown rice. Mean temperature for 30 days from heading was more closely correlated with grain filling and tastes of cooked rice than those for 40 days. Though, the optimum mean temperature for the best taste of cooked rice for 30 days after heading was 22.1 to $23.1^{\circ}C$ depending on varieties, in general, 1,000 grain weight and cooked rice taste were the highest in the mean temperature of $22.2^{\circ}C$ for 30 days from heading. But grains were poorly ripened in case of the mean temperature lower than $21.0^{\circ}C$ for 30 days after heading. Therefore, for the better taste of cooked rice in Korea, the developing new rice varieties and cultivation method should be focused to adjust the mean temperature within $22-23^{\circ}C$ during the period of 30 days after heading.

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.3
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• pp.435-443
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• 2012

This study investigated soil carbon storage and microbial activities influenced by different management practices in rice paddies and pastures. Soils under a single-crop farming of rice (CON) and rice-Italian ryegrass rotation farming (IRG) were compared in Jangheung, Jeollanam-do, Seocheon and Cheonan, Chungcheongnam-do. Soils from pastures were analyzed to investigate the effect of duration period (P1, P2, P3) in Namwon, Jeollabuk-do and Seosan, Chungcheongnam-do. In rice paddy, total and particulate carbon (PC) concentrations in the IRG soils were significantly higher than those in the CON soils both in Jangheung and Seocheon where the IRG has been established for three years, whereas carbon concentrations were not significantly different in Cheonan where IRG planting history is only one year. In rice paddy soils, PC was suggested as an early indicator to monitor changes in soil carbon storage followed by adopting different management practices. In pasture, total and PC concentrations increased with duration period especially in the 0-5 cm soils. Contrary to the rice paddy soils, the magnitude of change in PC concentration is not as great as that in total carbon concentration, implying that there is a need to develop a new early indicator other than PC using different fractionation scheme. The soil carbon storage in pasture also increased with years since establishment and the increasing rate was significantly greater in the early stage (0-5 yrs) than the later one (> 5 yrs). Microbial activities measured from fluorescein diacetate (FDA) hydrolysis analysis were significantly lower in the IRG soils than CON soils, whereas no difference was observed in the pastures of different ages. This shows that FDA activity is not a sensitive indicator to differentiate soil qualities influenced by management practices if it is used by itself.

• Journal of Korean Society of Forest Science
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• v.102 no.3
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• pp.345-354
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• 2013

To understand the community structures of the vegetation of the beaches and coastal dunes of Seocheon-gun, Boryeong-si, Anmyeon-do, Taean-gun in Chungcheongnam-do and Buan-gun in Jeollabuk-do at the west coast of South Korea, a plant sociological vegetation survey was carried out to make a classification of correlation vegetation communities, a cluster analysis and an inorganic component analysis on the soil and plant body. Regarding the vegetation of the coastal dunes, plant communities were classified into 31 communities by correlation dominant species, and as a result of a cluster analysis on the vegetation communities, they were classified into five vegetation types such as Calystegia soldanella community, Rosa rugosa community, Imperata cylindrica community, Vitex tend community and Elymus mollis community. The soil pH was highest in Seocheon area ($7.54{\pm}1.18$) while lowest in Buan area ($6.29{\pm}2.15$), and regarding inorganic components, the nitrogen content was highest in Robinia while lowest in Imperata cylindrica. The soil PH of vegetation I was highest (8.23) among the five vegetation types, and the organic matter was lowest (71.58). As a result of CCA ordination analysis to examine the correlation among environmental factors, Calystegia soldanella community, Rosa rugosa community and Imperata cylindrica community among the five vegetation types were distributed while they were not affected by soil environmental elements, but Vitex tend community and Elymus mollis community were distributed mainly at the places with high $K^+$ content in the soil.

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.146-154
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• 2016

In this study, understanding the habitats on spot-billed duck that wintering-breed in the korea, which using the GPS-Mobile based Telemtry (WT-200), I tried to take advantage as the basic data of the protection and management of the habitats of the waterbirds of Korea. Study area is Gyeonggi-do Bokhacheon, Chonmichon, Chungcheongnam-do Gokugyochon, Chungcheongbuk-do Byeongcheoncheon, Jeollabuk-do Mangyunggang, which Five rivers and Jeju Island reservoir, I have attached the tracking of the location(WT -200) to the twenty-five spot-billed ducks. among twenty five ducks, twelve ducks moved to overseas countries, the arrival site was China, North Korea, Russia. Moving average distance was 683km, the largest distance was 1,238km. The average northbound starting date was April 26. The average daily movement distance of thirteen ducks remaining in the domestic country is $1.0{\pm}0.89km$, maximum travel distance was 23.8km. The average daily movement distance of wintering prior to average going north dating is a 0.9km, is the largest 14.6km, the breeding season is an average 1.3km, maximum was 14.4km. Spot-billed duck used the rivers in domestic country most frequently, following was rice field, a filed, reservoir. It used the river most frequently during the wintering period, in the breeding season it used paddy paddies most frequently. While wintering, during the day and night's utilization rate was the highest in the river, but utilization rate was incleased on filed, paddy filed at night. During breeding season, daytime and night's utilization rate was the highest but, utilization rate was increased on river and utilization rate was decreased on river. In accordance with time change, spot-billed duck showed different tendency in paddy fields, and they utilized the filed adjacent to rivers mostly.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.272-280
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• 2013

This study aims to develop a standard diagnostic table for management and administration that oak mushroom cultivators of forestry households can utilize. By diagnosing their current level of management with the table, the cultivators themselves will be able to grasp and address their operational challenges better. The table is composed of; questions on the status of forestry households; columns for a series of management performance indices, and; questionnaire with 4 categories and 20 subcategories to check the current level of management and administration by the households. In order to prepare the standard diagnostic table for oak mushroom management, 196 forestry households throughout 10 areas - Cheong-yang, Gong-ju, Bu-yeo and Seocheon in Chungcheongnam-do, Mun-kyung and Ye-cheon in Gyeongsangbuk-do, Jin-an in Jeollabuk-do, Jangheung and Jang-seong in Jeollanam-do, and Jeju Islands - were interviewed with and a total of 190 questionnaires were acquired and made use of in the result analysis. Then, the score on management level of each forestry household was determined in the way of aggregating scores from each subcategory. The overall average score of every household was calculated at 62.2 point with more than half of the respondents, 54.7%, belonging to the range of 60 to 80. When considered by regional groups, the average score of Jin-an was the lowest with 57.6 point while that of Jang-seong was the highest with 69.6 point. In case of the 'cultivation management' category, there were a lot of cultivators who expressed a negative awareness of the term 'pest control' because they had a tendency to think the term in connection with 'herbicides or pesticides'. So it is inevitable to adapt and modify existing groups and grades to make sure that the cultivators can make a right choice without confusing the concept 'pest control' with 'herbicides or pesticides'. Meanwhile, the average scores of 'management and administration' categories were mostly low. It was remarkable in these categories that forestry households in Jeolla province, which had remained in lower ranks in the other three categories, recorded higher scores than those in Chungcheong province, boasting a relatively high level of management and administration.

• Korean Journal of Breeding Science
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• v.49 no.4
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• pp.420-427
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• 2017

'Pungwonmi', a new sweetpotato variety, was developed for table use by Bioenergy Crop Research Institute, National Institute of Crop Science (NICS), RDA in 2014. This variety was derived from the cross between 'Benisatsuma' and 'Luby3074' in 2006. The seedling and line selections were performed from 2007 to 2009, and preliminary and advanced yield trials were carried out from 2010 to 2011. The regional yield trials were conducted at five locations from 2012 to 2014, and it was named as 'Pungwonmi'. This variety has cordate leaf shape, and its leaves, stems, nodes, and petioles are green. Storage root of 'Pungwonmi' has an elliptical shape, red skin, and light orange flesh. 'Pungwonmi' was moderately resistant to fusarium wilt, and resistant to root-knot nematode. Dry matter content was 31.2%, and texture of steamed storage root was intermediate. Total sugar content of raw and steamed storage roots of 'Pungwonmi' was higher than that of 'Yulmi'. ${\beta}$-carotene content of 'Pungwonmi' was 9.1 mg/100g DW. Yield of marketable storage root over 50 g of 'Pungwonmi' was 24.3 MT/ha under the early season culture, which was 46% higher than that of 'Yulmi'. The number of marketable storage roots per plant was 2.8 and the average weight of marketable storage root was 156 g under the optimal and late season culture. Marketable storage root yield of 'Pungwonmi' was 24.1 MT/ha under the optimum and late season culture, which was 26% higher than that of 'Yulmi'. (Registration No. 6428).

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.243-254
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• 2019

With the recent accelerated policy-making and interests in new renewable energy, plans to develop and supply the new renewable energy have been devised across multiple regions in Korea. Solar energy, in particular, is being applied to small-scale power supply in provincial areas, as solar cells are used to convert solar energy into electric energy to produce electric power. Nonetheless, in the case of solar power plants, the need for a large stretch of land and considerable sum of financial support implies that the planning step should take into consideration the most suitable meteorological and geographical factors. In this study, the proxy variables of meteorological and geographical factors associated with solar energy were considered in analyzing the vulnerable areas regarding the photovoltaic power generation facility across the nation. GIS was used in the spatial analysis to develop a map for assessing the optimal location for photovoltaic power generation facility. The final vulnerability map developed in this study did not reveal any areas that exhibit vulnerability level 5 (very high) or 1 (very low). Jeollanam-do showed the largest value of vulnerability level 4 (high), while a large value of vulnerability level 3 (moderate) was shown by several administrative districts including Gwangju metropolitan city, Jeollabuk-do, Chungcheongbuk-do, and Gangwon-do. A value of vulnerability level 2 (low) was shown by the metropolitan cities including Daegu, Ulsan, and Incheon. When the 30 currently operating solar power plants were compared and reviewed, most were found to be in an area of vulnerability level 2 or 3, indicating that the locations were relatively suitable for solar energy. However, the limited data quantity for solar power plants, which is the limitation of this study, prevents the accuracy of the findings to be clearly established. Nevertheless, the significance of this study lies in that an attempt has been made to assess the vulnerability map for photovoltaic power generation facility targeting various regions across the nation, through the use of the GIS-based spatial analysis technique that takes into account the diverse meteorological and geographical factors. Furthermore, by presenting the data obtained for all regions across the nation, the findings of this study are likely to prove useful as the basic data in fields related to the photovoltaic power generation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.4
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• pp.273-281
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• 2018

Wet hill seeding (WHS) is one of the more famous labor and money saving methods technology used for rice cultivation. In WHS, rice standing percentage and weedy rice occurrence are the most important factors considered to secure a rice yield. We investigated the optimum seeding date of WHS in the Southern Plain area of South Korea. Weedy rice needed two weeks at $15^{\circ}C$ to show over 80% emergence. Germinated rice seed grown at $20^{\circ}C$ needed over for 10 days to achieve a shoot length over 3 cm. In field cultivation, the mean temperature for ten days after seeding showed a highly positive correlation with rice standing rate, spikelet number per square meter and yield index that favorably compared to machine transplanting. With these data, we suggest that the optimum seeding date of WHS that can secure over 98% of yield index of machine transplanting in Southern part of Korea is May. 21~Jun. 5 in Honam and May. 16~Jun. 5 in Yeongnam area.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.3
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• pp.149-155
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• 2021

Early warning systems for weather risk management in the agricultural sector have been developed to predict potential wind damage to crops. These systems take into account the daily maximum wind speed to determine the critical wind speed that causes fruit drops and provide the weather risk information to farmers. In an effort to increase the accuracy of wind risk predictions, an artificial neural network for binary classification was implemented. In the present study, the daily wind speed and other weather data, which were measured at weather stations at sites of interest in Jeollabuk-do and Jeollanam-do as well as Gyeongsangbuk- do and part of Gyeongsangnam- do provinces in 2019, were used for training the neural network. These weather stations include 210 synoptic and automated weather stations operated by the Korean Meteorological Administration (KMA). The wind speed data collected at the same locations between January 1 and December 12, 2020 were used to validate the neural network model. The data collected from December 13, 2020 to February 18, 2021 were used to evaluate the wind risk prediction performance before and after the use of the artificial neural network. The critical wind speed of damage risk was determined to be 11 m/s, which is the wind speed reported to cause fruit drops and damages. Furthermore, the maximum wind speeds were expressed using Weibull distribution probability density function for warning of wind damage. It was found that the accuracy of wind damage risk prediction was improved from 65.36% to 93.62% after re-classification using the artificial neural network. Nevertheless, the error rate also increased from 13.46% to 37.64%, as well. It is likely that the machine learning approach used in the present study would benefit case studies where no prediction by risk warning systems becomes a relatively serious issue.