• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.2
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• pp.1126-1139
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• 2014

World is experiencing abnormal weather caused by urbanization and industrialization increasing greenhouse gas and one of these phenomenon domestically happening is flood and drought. The increase of green-house gases is due to urbanization and industrialization acceleration which are causing abnormal climate changes such as the El Nino and a La Nina phenomenon. It is expected that there will be many difficulties in water management, especially considering the topography and seasonal circumstances in Korea. Unlike in the past, a variety of water conservation initiatives have been undertaken like the river-management flow and water capacity expansion projects. To meet the increasing demand for water resources, new environmentally-friendly small and medium-sized dams have been built. Therefore, the development of a new paradigm for water resources management is essential. This study shows that additional security is needed for potential water resources through diversion tunnels and is very important to consider for future water supplies and situations. Using RCP 6.0 and RCP 8.5 in representative concentration pathway climate change scenario, specific hydrologic data of study basin was produced to analyze past observed basin rainfall tendency which showed both scenario 5%~9% range increase in rainfall. Through sensitivity analysis using objective function, population in highest goodness was 1000 and cross rate was 80%. In conclusion, it is expected that the results from this study will help to make long-term and stable water supply plans by using the potential water resource evaluation model which was applied in this study.

• Journal of Korea Water Resources Association
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• v.45 no.12
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• pp.1259-1273
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• 2012

In this study, a watershed-based surface water and groundwater integrated model, SWAT-MODFLOW was used to quantify the stream flow depletion due to groundwater pumping for the Sinduncheon watershed. Complex water use conditions such as water taken from a stream, sewage disposal release, irrigation from agricultural reservoir, groundwater pumping were considered for simulations. In particular, the model was revised to reflect the effects of reservoir operation and return flow from the used groundwater on streamflow variation. The simulated results showed that the groundwater pumping at current status has induced the decrease of more than 10% in annual average streamflow and 40% in drought flow at the outlet of the Sinduncheon watershed, The simulated results also revealed that the vast water withdrawals at green house areas during winter season have dramatically changed streamflow from April to June. The streamflow depletion was mainly attributed to pumping wells located within the distance of 300 m from the stream for Sinduncheon watershed.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.2
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• pp.77-84
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• 2001

To increase the utilization of soil survey results, classification of morphological types of paddy soils which was consisted of land-form, texture, and drainage classes etc. was attempted as an interpretive classification system. The paddy soils could be classified into 37 types. Among the types, the "Lfi(Fine loamy textured semi-wet paddy on local valley and fans)" acreage of about 224 thousand ha, "Lfd(Fine loamy textured dry paddy on local valley and fans)" 160 thousand ha. "Lmi(Coarse loamy textured semi-wet paddy on local valley and fans)" 112 thousand ha, and "Lkd(Loamy skeletal dry paddy on local valley and fans)" 93 thousand ha, respectively were the dominant types. The possibility of double cropping, plastic film house, green manure cropping etc., and that for soil managements such as application of raw straw or compost, deep plowing or adding fine earth materials, mole drainage, susceptibility to erosion or reduction injury etc. for each types were recommended.

• Horticultural Science & Technology
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• v.31 no.5
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• pp.538-543
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• 2013

During summer in Korea, the excessively high temperature causes growth retardation and quality reduction in cut roses grown in greenhouse. Mist treatments were conducted to reduce the temperature and avoid quality reduction of cut roses. The temperature change in the greenhouse, growth and quality of cut roses, and injuries caused by insects or fungi were investigated during mist treatment. Daily maximum temperature reduced as the number of mist treatment increased, resulting in $6^{\circ}C$ reduction by mist treatment for 10 seconds at 5 min interval. This temperature reduction occurred only when maximum temperature was over $40^{\circ}C$ in greenhouse, and not when it was less than $40^{\circ}C$ or rainy and/or cloudy day. Plant height and fresh weight of the cut roses were increased at the range of 10-20% by mist treatment. As frequency of mist treatment increased, however, malformed flowers increased and vase life of cut rose was largely shortened. The injuries by insects like as beet armyworm larvae and scale insect increased as well. In conclusion, it is recommended that mist treatment must be used when the daily maximum temperature in a green house is over $40^{\circ}C$ and forecasting for disease or insects should be conducted as well.

• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.715-725
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• 2017

Importance of climate change and its impact on agriculture and environment has increased with the rise in the levels of Green House Gases (GHGs) in the atmosphere. To slow down the speed of climate change, numerous efforts have been applied in industrial sectors to reduce GHGs emission and to enhance carbon storage. In the agricultural sector, several types of research have been performed with emphasis on GHGs emission reduction; however, only a few work has been done in understanding the role of carbon sink on reduction in GHGs emission. In this study, we investigated ecosystem carbon balance and soil carbon storage in an agricultural paddy field. The results obtained were as follows: 1) Evaluation of soil C sequestration in paddy field was average $3.88Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, average $3.22Mg\;C\;ha^{-1}$ following NPK+hairy vetch treatment, and average $1.97Mg\;CO_2\;ha^{-1}$ following NPK treatment; and 2) Net ecosystem production (NEP) during the paddy growing season was average $14.01Mg\;CO_2\;ha^{-1}$ following NPK+hairy vetch treatment, average $12.60Mg\;CO_2\;ha^{-1}$ following NPK+rice straw compost treatment, and average $11.31Mg\;CO_2\;ha^{-1}$ following NPK treatment. Therefore, it is proposed that organic matter treatment can lead to an increase in soil organic carbon accumulation and carbon sock of crop ecosystem in fields compared to chemical fertilizers.

• Korean Journal of Breeding Science
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• v.43 no.3
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• pp.180-183
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• 2011

'Yeomyeong', a new welsh onion (Allium fistulosum L.) variety, is developed by the Bioenergy Crop Research Center, NICS, RDA in 2004. This variety, as interspecific $F_1$ hybrid, is developed by a cross between onion (Allium. cepa L.) and welsh onion (A. fistulosum L). The first cross was conducted in 2003 between MOS8, onion male sterile line and G2, welsh onion inbred line. Horticultural and yield characteristics of this hybrid $F_1$ line was investigated in greenhouse for 2 years from 2004 to 2005 with fall cropping cultivation. It has a single pseudostem plant type, anthocyanin-colored pseudostem, and male sterile umbel. It showed intermediate plant type of the maternal parents in overall plant characteristics. 'Yeomyeong' is fall sawing variety and has higher plant height and pseudostem length than that of check variety 'Gumjang'. The yield potential of this variety was about 130.1MT/ha in greenhouse in spring harvseting season. This variety would be adaptable to the fall sowing cultivation in green house.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.6
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• pp.503-513
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• 2016

In order to reduce the green-house gas exhaustion, International Maritime Organization (IMO) has been reinforcing carbon gas regulations. Due to the regulations, a lot of competitions for designing Eco ship in the shipbuilding industry are progressing now. It is faced with the necessity of reducing hull weight by combining automated systems for optimal compartment arrangement with hull structural design. Most researches on optimum structural design method have been consistently in progress and applied to minimize weight and cost of mid-ship section in preliminary ship design stage based on analytical structural analysis method on fixed compartment arrangement. In order to reduce design period and to improve international technical competitiveness by shortening the period of hull structural design and enhancing design accuracy, it has been felt necessity to combine optimized compartment arrangement with optimum design of ship structure based on the international regulations and rules. So in this study, the automated design algorithm for longitudinal members has been developed to combine automated algorithm of compartment arrangement with hull structural design system for oil tanker. The SeaTrust-Hullscan software developed by Korean Register is used to perform ship structural design for mother ship and selected design cases. The effect of weight reduction is verified with comparison of ship weight between mother ship and the cases suggested in this study.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.1
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• pp.36-42
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• 2007

Korean paddy soils have long been almost uniformly managed throughout the whole country with flooded, deep tillage, puddlling, transplanting, and uncovering after harvest. Management of soil organic carbon could be more important in the sources of green house gases. However, soil organic carbon dynamics were not been studied for Korean paddy soils. Therefore, we evaluated the changes in soil organic carbon (SOC) of paddy soils between 1999 and 2003 at the same locations nationwide except islands. Soil organic carbon tends to increase in Inceptisols, which is predominant soil order for Korean paddy soils, from 1999 to 2003. Soil organic carbon increases in topographically plain paddy soils was greater than in valley soils, and was considerably high in predominant types of paddy soils (i.e., well adapted paddy soils, sandy paddy soils, and poorly drained paddy soils) but low and stable in the saline paddy soils. We also found that clay paddy soils are greater in soil organic carbon than sandy paddy soils. Through this study, we concluded that a proper management of paddy soils could contribute to soil organic carbon storage, which imply that the Korean paddy soils could help to enhance carbon dioxide sequestration via soil organic matter into the soil.

• Korean Journal of Breeding Science
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• v.40 no.4
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• pp.466-469
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• 2008

A new kidney bean cultivar, "Hwanghyeob 1" was developed at the National Institute of Crop Science in 2005. "Hwanghyeob 1" was selected from a cross between KLG50064 and KLG50073. It has determinate growth habit, white flower, yellow pod color, oval shape of crossed section of pod at the harvesting time for edible pod, white seed coat and middle seed size (21.7 grams per 100 seeds). The average yield of edible pod of "Hwanghyeob 1" was 23.55 M/T per hectare in the yield trials which was carried out at the green house in spring and autumn in 2005. This yield level was 4 percent higher than that of the check cultivar "Kangnangkong 1".

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.699-702
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• 2010

Anthracnose is a major limiting factor of the watermelon production in Korea. A mid-late maturing watermelon line, 'Hanbit' with resistance to anthracnose (Colletotrichum orbiculare) race 1 and 3, was developed by the cross between anthracnose resistant cultivar 'AU-Producer' and high quality inbred line '920533' at the National Institute of Horticultural and Herbal Science, Rural Development Administration (RDA). 'Hanbit' produces 5.4 to 9.5 kg of red flesh fruits with clear stripes on skin. Average soluble solid contents are ranged from 10.4 to 11.2$^{\circ}$Bx. The yield and quality of 'Hanbit' was comparable to or better than those harvested from the popular commercial cultivars. 'Hanbit' can be cultivated in open fields and under the protected green house condition. In addition to the commercial production, it can be used as a resistant material in $F_1$ hybrid breeding program.