• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.1
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• pp.70-74
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• 2015

An LED plant factory farm is an alternative way to grow crops regardless of weather, season, and blight in such times of climate change. In recent years, it is a currently active and vibrant research field. The industry, which ranges from leaf vegetables to high value products, is expanding. This study was conducted to test tthe response of LED (Light-emitting diode) irradiation on the growth characteristics and ginsenoside levels indoors, in order to find out suitable light conditions. Ginseng seedling was transplanted from a styrofoam pot ($L{\times}W{\times}D$:$495{\times}315{\times}215mm$, inside diameter) into a closed plant production system in four blue LED (BL) and red LED (RL) different ratios of 1:1, 1;2, 1:3, 1:4 in a temperature range of $20{\sim}25^{\circ}C$, relative humidity of between 55 and 65%, and a 12-hour photoperiod. The LED irradiation shows the highest levels were found at 1:1 of BL and RL ratio at $61.21{\mu}mol\;s^{-l}m^{-2}$, 1:2 ratio $68.55{\mu}mol\;s^{-l}m^{-2}$, 1:3 ratio $63.85{\mu}mol\;s^{-l}m^{-2}$ and 1:4 ratio $62.41{\mu}mol\;s^{-l}m^{-2}$ from highest to lowest respectively. After analyzing from shoot and root 2 yers old ginseng plant which were cultivated under 1:3 irradiation of BL and RL ratio, it generally showed a positive effect under a 1:3 ratio of BL and RL.

• Korean Journal of Environmental Biology
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• v.25 no.3
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• pp.223-227
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• 2007

Crop loss and damage by wildlife are becoming more serious to residents inside and around National Parks of Korea annually. It could be caused by small size of Parks, which is couples of ten $km^2$ only, and more than a third of total parks' areas are belonging to privates. Wild boar (Sus scrofa) is one of the most harmful pests in nationwide. Treading down crop field using as bedding or resting site are major damaged types and foraging behavior is following. Besides of boars, Korean water deer (Hydropotes inermis), racoon dog (Nyctereutes procyonoides), and badger (Meles meles) are another serious pests. Mainly, farm products planted in upland, such as corns, sweet potatoes, cabbages, etc. are harmed easily, a rate reaches up to 76.9% of whole losses. 92.4% (n=187) of interviewees, who are mostly seniors, cultivate small crop fields smaller than 1 ha. Crop damage would be started from June to late November, time differences are happened due to latitude, climate condition, and crop differences of National Parks. Dusting animal repellents are easier and widespread methods to prevent animal foraging to crop fields and installing noisy makers using gun powder and setting up scarecrows are traditional methods for repelling animals. Nevertheless, effects of these self-defence are turned out to be useful soon after labors done only. Since legal compensation for crop damages by wildlife are not prepared systematically so far, crop loss are rarely reported to local government by most farmers. Systematic and objective methods for quantifying of crop loss by wildlife and population managements system should be offered urgently to well-managed animals habitat and residents' living inside National Parks.

• Journal of Korean Society of Transportation
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• v.33 no.4
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• pp.357-367
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• 2015

This study aims to propose integrated management strategies based on the relationship between co-benefits and total benefits of greenhouse gases and air pollutant emissions for establishing a transport and environmental policy. The results show that the integrated management of the following policies: 'Car Free Day' and 'Early Scrapping of Decrepit Diesel Vehicle', which are used for reducing reduce gasoline and diesel, can together reduce both PM and $CO_2$ emissions and increase total benefits. In addition, the integrated management of 'Car Free Day' with environment policies and 'Congestion Charge' with environment policies simultaneously controls the three factors which influence emissions, including travel volume, travel speed and emissions factor, and was found to be effective in terms of co-benefits. This study reduces both air pollutants, which are harmful to health, and greenhouse gas emissions, which influence climate change, and improves the efficiency of policy through the integrated management of policies.

• Journal of Plant Biotechnology
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• v.43 no.3
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• pp.383-390
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• 2016

To determine whether FT-IR spectral analysis based on multivariate analysis could be used to discriminate Chinese cabbage breeding line at metabolic level, whole cell extracts of nine different breeding lines (three paternal, three maternal and three $F_1$ lines) were subjected to Fourier transform infrared spectroscopy (FT-IR). FT-IR spectral data of Chinese cabbage plants were analyzed by principal component analysis (PCA), partial least square discriminant analysis (PLS-DA), and hierarchical clustering analysis (HCA). The hierarchical dendrograms based on PLS-DA from two of three cross combinations showed that paternal, maternal, and their progeny $F_1$ lines samples were perfectly separated into three branches in breeding line dependent manner. However, a cross combination failed to fully discriminate them into three branches. Thus, hierarchical dendrograms based on PLS-DA of FT-IR spectral data of Chinese cabbage breeding lines could be used to represent the most probable chemotaxonomical relationship among maternal, paternal, and $F_1$ plants. Furthermore, these metabolic discrimination systems could be applied for rapid selection and classification of useful Chinese cabbage cultivars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.1
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• pp.43-49
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• 2015

This experiment was conducted to evaluate the agronomic characteristics and forage productivity of Italian ryegrass cultivars in Yecheon, Kyeongbuk from 2011 to 2013. The experimental design was a randomized complete block design (RCBD) with three replications. Italian ryegrass cultivars were seeded on Sep. 26 in 2011 and Sep. 25 in 2012. The Italian ryegrass cultivars were harvested on the heading date of the variety. The cold-resistance of domestic cultivars was stronger than other foreign varieties. Among early-maturing cultivars, the dry matter (DM) yield of the "Kowinearly" was 10,031 kg/ha, which was significantly higher than that of other cultivars (p<0.05). In medium-maturing cultivars, the DM yield of the "Kowinmaster" and "Tam 90" were 10,484 and 8,191 kg/ha, respectively. Of the two, the former's DM yield was higher than the latter's (p<0.05). Among late-maturing cultivars, the DM yield of "Hwasan 104" was 10,641 kg/ha, which was similar to that of "Hwasan 101" and significantly higher than the other late-maturing cultivars (p<0.05). According to the results obtained from this study, an early-maturing variety with cold-tolerance and high productivity is required for the paddy field cultivation of an Italian ryegrass cultivar after rice harvest in the mid-northern region of Korea. A medium- or late-maturing variety is more advantageous for the field cultivation of the maximum quantity that is possible. In conclusion, to select which variety/ies to grow, the climate of the growing area, weather conditions, and the cropping system must all be considered.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.1
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• pp.16-23
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• 2000

A topography-precipitation relationship derived from the southern part of Korean Peninsula was applied to North Korea where climate stations are few and widely separated. Two hundred and seventy seven rain gauge stations of South Korea were classified into 8 different groups depending on the slope orientation (aspect) of the region they are located. Monthly precipitation averaged over 10 year period (1986-1995) was regressed to topographical variables of the station locations. A 'trend precipitation' for each gauge station was extracted from the precipitation surface interpolated from the monthly precipitation data of 24 standard stations of the Korea Meteorological Administration and used as a substitute for y-axis intercept of the regression equation. These regression models were applied to the corresponding regions of North Korea, which were identified by slope orientation, to obtain monthly precipitation surface for the aspect regions. 'Trend precipitation' from the 10 year data of 27 North Korean standard stations was also used in the model calculation. Output grids for each aspect region were mosaicked to form the monthly and annual precipitation surface with a 1km$\times$1km resolution for the entire territory of North Korea. Spatially averaged annual precipitation of North Korea was 938 mm with the standard deviation of 246 mm.

• Korean Journal of Agricultural and Forest Meteorology
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• v.13 no.1
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• pp.41-46
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• 2011

Reliable information on the surface solar radiation is indispensable for rebuilding food production system in the famine plagued North Korea. However, transfer of the related modeling technology of South Korea is not possible simply because raw data such as solar radiation or sunshine duration are not available. The objective of this study is restoring solar radiation data at 27 synoptic stations in North Korea by using satellite remote sensing data. We derived relationships between MODIS radiation estimates and the observed solar radiation at 18 locations in South Korea. The relationships were used to adjust the MODIS based radiation data and to restore solar radiation data at those pixels corresponding to the 27 North Korean synoptic stations. Inverse distance weighted averaging of the restored solar radiation data resulted in gridded surfaces of monthly solar radiation for 4 decadal periods (1983-1990, 1991-2000 and 2001-2010), respectively. For a direct application of these products, we produced solar irradiance estimates for each sub-grid cell with a 30 m spacing based on a sun-slope geometry. These products are expected to assist planning of the North Korean agriculture and, if combined with the already prepared South Korean data, can be used for climate change impact assessment across the whole Peninsula.

• Korean Journal of Environmental Agriculture
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• v.39 no.3
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• pp.171-177
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• 2020

BACKGROUND: Recently, biomass conversion from agricultural wastes to carbon-rich materials such as biochar has been recognized as a promising option to maintain or increase soil productivity, reduce nutrient losses, and mitigate greenhouse gas emissions from the agro-ecosystem. This experiment was conducted to select an optimum conditions for enhancing the NH₄-N adsorption capacity of rice hull activated biochar. METHODS AND RESULTS: For deciding the proper molarity of KOH for enhancing its porosity, biochars treated with different molarity of KOH (0, 1, 2, 4, 6, 8) were carbonized at 600℃ in the reactor. The maximum adsorption capacity was 1.464 mg g^-1, and an optimum molarity was selected to be 6 M KOH. For the effect of adsorption capacity to different carbonized temperatures, 6 M KOH-treated biochar was carbonized at 600℃ and 800℃ under the pyrolysis system. The result has shown that the maximum adsorption capacity was 1.76 mg g^-1 in the rice hull activated biochar treated with 6 M KOH at 600℃ of pyrolysis temperature, while its non-treated biochar was 1.17 mg g^-1. The adsorption rate in the rice hull activated biochar treated with 6 M KOH at 600℃ was increased at 62.18% compared to that of the control. Adsorption of NH₄-N in the rice hull activated biochar was well suited for the Langmuir model because it was observed that dimensionless constant (R_L) was 0.97 and 0.66 at 600℃ and 800℃ of pyrolysis temperatures, respectively. The maximum adsorption amount (q_m) and the bond strength constants (b) were 0.092 mg g^-1 and 0.001 mg L^-1, respectively, for the rice hull activated biochar treated with 6 M KOH at 600℃ of pyrolysis. CONCLUSION: Optimum condition of rice hull activated biochar was 6M KOH at 600℃ of pyrolysis temperature.

• Research in Plant Disease
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• v.16 no.2
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• pp.176-182
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• 2010

Occurrence of plant diseases is dependent on various factors in the agricultural system. Due to recent extensive environmental climate changes, i.e. global warming, agricultural systems such as planting dates and cultivars are being affected. Gradual transition in disease occurrence and incidence in the agricultural fields can also be affected by direct and/or indirect environmental changes. In this study, we evaluated disease occurrence and incidence in soybean plants to investigate whether it could be related with cultivars, planting dates and geographical differences in Korea in 2008. Soybean cultivars including 'Taekwang', 'Pungsan', 'Cheongja 3', 'Saeol', and 'Dawon' were planted in four different dates, May 15, June 1, June 15, and June 30, in two locations, Suwon, and Naju. Soybean diseases such as wild fire and bacterial pustule were mainly found depending on cultivars, planting dates, and areas. Wild fire occurred severely on cv. 'Taekwang' while bacterial blight did on cv. 'Dawon' among tested cultivars. Disease developments of wild fire and bacterial blight generally decreased in delayed planting regardless of cultivars.

• Journal of Korea Water Resources Association
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• v.43 no.11
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• pp.995-1009
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• 2010

Accelerated soil erosion due to extreme climate change, such as increased rainfall intensity, and human-induced environmental changes, is a widely recognized problem. Existing soil erosion models are generally based on the gross erosion concept to compute annual upland soil loss in tons per acre per year. However, such models are not suitable for event-based simulations of erosion and deposition in time and space. Recent advances in computer geographic information system (GIS) technologies have allowed hydrologists to develop physically based models, and the trend in erosion prediction is towards process-based models, instead of conceptually lumped models. This study aims to propose an effective and robust distributed rainfall-sediment yield-runoff model consisting of basic element modules: a rainfall-runoff module based on the kinematic wave method for subsurface and surface flow, and a runoff-sediment yield-runoff model based on the unit stream power method. The model was tested on the Cheoncheon catchment, upstream of the Yongdam dam using hydrological data for three extreme flood events due to typhoons. The model provided acceptable simulation results with respect to both discharge and sediment discharge even though the simulated sedigraphs were underestimated, compared to observations. The spatial distribution of erosion and deposition demonstrated that eroded sediment loads were deposited in the cells along the channel network, which have a short overland flow length and a gentle local slope while the erosion rate increased as rainfall became larger. Additionally, spatially heterogeneous rainfall intensity, dependant on Thiessen polygons, led to spatially-distinct erosion and deposition patterns.