• Korean Journal of Weed Science
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• v.15 no.4
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• pp.289-297
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• 1995

Field experiments were conducted to evaluate the competitive characteristics of weeds with direct-seeded rice. In both dry- and water-seeded rice a weeds) started to grow over the plant height of rice from 45 days after seeding, and there was a great difference in plant height between rice and weeds from 75 days after seeding. Dry weights of weeds drastically increased from 30 days after seeding in both dry- and water-seeded rice, and the increase of dry weight was faster in dry-seeded rice than in water-seeded rice with time. Although weeds competed with rice at earlier growth stages, they did not reduce rice yields and its components until competition period of 75 days after seeding. Required period of weed free at the beginning of the season was 30 to 45 days from seeding in order to avoid any yield loss. The numbers of panicle per plant, spikelets per panicle, grain weight and yield of rice in dry-seeded rice had highly negative correlations with the growth ratios of Echinochloa crus-galli, Ludwigia prostrata, Cyperus difformis, Bidens frondosa, and Cyperus serotinus. In water-seeded rice, the number of plants, panicle per plant, spikelets per panicle and yield had highly negative correlations with growth rate of Echinochloa crus-galli, but the percentage of filled spikelet had negative correlation with Cyperus difformis. Research indicated that in direct-seeded rice weed competition with rice started from 30 days after seeding and significant yield loss by weed competition occurred from 75 days after seeding.

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.1
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• pp.43-50
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• 2009

Two experiments were conducted to evaluate the effects of nitrogen (N) application level and regrowth period on the fatty acid (FA) concentration and forage production of tall fescue (Festuca arundinacea Schr.) and bermudagrass (Cynodon dactylon (L.) Pers.). N was applied at 0, 50 and 100 kg/ha, and swards were cut after regrowth periods (15d, 30d and 45d). Concentrations of Individual FA were determined by gas chromatography. FA composition of tall fescue contains a high proportion ($87{\sim}88%$) of total FA contents as palmitic (C16:0), linoleic (C18:2) and linolenic acid (C18:3). The FA composition was not affected by N application, but a longer regrowth period significantly (p<0.05) decreased the composition of linolenic acid (C18:3) and increased those of linoleic acid (C18:2). The FA composition of bermudagrass was not affected by N application, but a longer regrowth period significantly (p<0.001) decreased the composition of linoleic (C18:2) and linolenic acid (C18:3). Linoleic and linolenic acfd of tall fescue were higher than those of bermudagrass. Dry matter (DM) yield of bermudagrass was significantly (P<0.05) affected by N application level and regrowth period. DM yield was higher at high N application and was higher at longer regrowth period. The crude protein concentration was higher at high N application and was low at longer regrowth period. Application of nitrogen fertilizer Increases dry matter (DM) yield and crude protein (CP) content of bermudagrass. These studies demonstrate opportunities to affect the FA concentration and composition of FA in forage through management strategies, which could affect milk FA composition.

• Journal of The Korean Society of Grassland and Forage Science
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• v.37 no.2
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• pp.132-139
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• 2017

This study was conducted to find out the effects of over seeding using new grass varieties orchardgrass 'Kordione' and 'Onnuri', and tall fescue 'Greenmaster' on botanical composition and dry matter productivity from 2013 to 2016 in low productivity hilly pasture, middle area of Korea. There were used 3 grass seed mixture types made of different compositions and amounts {T1: control - no over seeding, T2: tall fescue (TF) 'Greenmaster' $18kg\;ha^{-1}$, orchardgrass (OG) 'Kordione' $9kg\;ha^{-1}$, Perennial ryegrass (PRG) 'Linn' $5kg\;ha^{-1}$, and Kentucky bluegrass (KBG) 'Kenblue' $2kg\;ha^{-1}$, T3: TF 'Greenmaster' $9kg\;ha^{-1}$, OG 'Kordione' $18kg\;ha^{-1}$, PRG 'Linn' $5kg\;ha^{-1}$, and KBG ' Kenblue' $2kg\;ha^{-1}$, T4: TF 'Greenmaster' $9kg\;ha^{-1}$, OG 'Onnuri' $18kg\;ha^{-1}$, PRG 'Linn' $5kg\;ha^{-1}$, and KBG 'Kenblue' $2kg\;ha^{-1}$}. In the botanical composition of grassland, T1 nearly remained constant in other seasons while ratio of weeds were increased in summer season. T2 was better than control (T1) in portion of grass ratio, which has increased by 80%. In the early time of establishment, the portions of OG were increased in T2, but TF rate was increased after 3 years later when grass was established. T3 and T4 showed a very similar patterns, grass ratio had increased by 80% and the portion of KBG had increased as time passed. T2 ($129,763kg\;ha^{-1}$) was showed the highest dry matter yield than other treatments (T1: $6,756kg\;ha^{-1}$, T3: 9641, and T4: 10,738) in 2016.

• Journal of the Society of Disaster Information
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• v.13 no.2
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• pp.233-248
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• 2017

Uniform laws and regulations and reasonable design is necessary for the prevention of possible fire in super high-rise building. To this end, this study focused on super high-rise and massive building-related architectural review performance-based design (PBD) evaluation disaster impact assessment (DIA), and provided fire engineering measures for improving fire prevention on the basis of performance-based design by analyzing the buildings subject to these systems and problems in terms of contents. Above all, in the aspect of law and standard improvement, first, with regard to dual parts of two statutes though significant portion of them has the same contents in performance-based design (PBD) evaluation and disaster impact assessment (DIA), it is necessary to operate the systems after making them conform with each other and consolidating or abolishing them. Second, if it is impossible to consolidate or abolish performance-based design (PBD) evaluation and disaster impact assessment (DIA), the areas of contents of performance-based design (PBD) evaluation and disaster impact assessment (DIA) should be precisely classified and established. Next, engineering improvement measures against fire hazard in super high-rise building are as follows. First, it is necessary to revise the provisions of straight-run stairs in special escape stairs. And in case of installing a mechanical smoke exhaust system instead of smoke vent, sandwich pressurization used in the United Stated should be permitted. Second, with regard to smoke control system for special escape stairs, it was shown that there was necessity for revising the standards in order to enable air to be supplied according to section in case of fire, carrying out performance-based design, and the like from the early design stages to the completion stages. In the future, it is expected that an epoch-making contribution will be made to a decrease in casualties and property damage due to fire in case of super high-rise building where the results can be reflected after carrying out a study on maintenance and carrying out an additional study on other considerations of super high-rise building together with reflecting the improvement measures provided in the above-mentioned study.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.248-253
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• 2015

This study was conducted to determine the impact of temperature elevated based on climate change scenario on growth and fruit quality of red pepper (Capsicum annuum L.) in walk-in plant growth chambers. The intraday temperatures of climate normal years (IT) were determined using intraday mean temperatures of climatic normal years (1971~2000) in the Andong Province during the growing season (May 1~July 30). Red pepper plants were cultivated under different temperatures (starting at IT rise by up to $6^{\circ}C$, $2^{\circ}C$ increment). Plant height, stem diameter, branch number, leaf number, fresh weight and dry weight increased under the temperatures higher than IT. The number of flower was the greatest under IT+$2^{\circ}C$ (mean temperature at $22.8^{\circ}C$). The total number and the weight of fruits were the highest under IT+$2^{\circ}C$. While the fruit weight, fruit length and fruit diameter decreased more than IT+$2^{\circ}C$ as the temperature increased gradually. These results concluded that in condition that the current diurnal temperature change cycle is maintained in Andong area, in accordance with climate change scenarios, when the temperature rise $2^{\circ}C$ higher than intraday temperature of Andong area the quantity of pepper fruits will increase while maintaining quality, but increases more than that degree yields are expected to decrease significantly. This result suggests that the fruit yield could increase under IT+$2^{\circ}C$ and fruit quality could maintain great, but the fruit yield could decrease under the temperatures higher than IT+$2^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.36 no.1
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• pp.63-71
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• 2009

Two experiments were conducted to investigate feed value of Yukmijihwangtang (herbal medicine) meal. In experiment 1, the chemical composition of Yukmijihwangtang ingredients was determined before and after extraction, and investigated the effects of partial substitution of dried Yukmijihwangtang meal on TMR for fattening cattle. In experiment 2, nine Korean native male goats were employed to investigate the palatability and ruminal parameters of Yukmijihwangtang meal silages. In experiment 1, the crude protein content after water extraction was higher in Alisma orientale Juzepczuk (Teaksa), and lower in Pachyma hoelen Rumph (Bokryeong). the crude fat content after water extraction was higher in Cornus officinalis Sieb. et Zucc (Sansuyu), and lower in other ingredients. ADF content after water extraction of Cornus officinalis Sieb. et Zucc (Sansuyu) was higher compared to those of Pachyma hoelen Rumph (Bokryeong) and Paeonia suffruticosa Andrews (Mokdanpi). Dioscorea japonica Thunberg (Sanyak) was the lowest in ADF content. Dry matter disappearance was increased by adding Yukmijihwangtang meal to TMR. In experiment 2, feed intakes of Yukmijihwangtang silage containing molasses (0.5 and 1%) for 30 min and 6 hr were significantly higher than that of control (0%) in Korean native goats. In various ruminl parameters, molasses addition to silage materials trended to increase total VFA, propionate and valerate contents, but trended to decrease iso-butylate, butylate and iso-valerate contents in Korean native goats. In conclusion, Yukmijihwangtang meal could be used as partial substitution of low level in TMR for fattening cattle. Molasses supplementation to silage materials contained with herbal medicine meal could improve its nutritional quality and palatability for Korean native goats. One percent level of molasses addition could give a useful effect in ensiling.

• Food Science and Preservation
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• v.24 no.5
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• pp.565-575
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• 2017

This study was carried out to investigate shelf-life and quality of fresh-cut Dungkunma (Dioscorea bulbifera) in order to elevate utilization of Dungkunma a fresh food. Before vacuum-packaging (in polyethylene/polypropylene film ($100{\mu}m$, $15{\times}20cm$, $75{\pm}2cmHg$) and storaging at $2^{\circ}C$, Dungkunma was peeled out and cut to dice type ($2.0{\pm}0.5cm^3$), and then washed and blanched using hot water (at $90{\pm}2^{\circ}C$ with 2% NaCl solution for 30 sec). Blanched Dungkunma was pre-dried at room temperature, $40^{\circ}C$ and $50^{\circ}C$ for removing surface water. Each peeled dice Dungkunma was packed 50 g in polyethylene/polypropylene film ($100{\mu}m$, $15{\times}20cm$) with vacuum treatment ($75{\pm}2cmHg$) and stored at $2^{\circ}C$ for 90 days. Hardness and adhesiveness of Dungkunma blanched by 2% NaCl and pre-dried at $50^{\circ}C$ (SB50) were the highest, but changes were the least during storage. Lightness and yellowness of stored Dungkunma in all treatments decreased slightly while redness increased during storage. Changes of color of SB50 was the least. Total concentration of aerobic bacteria in SB50 was $1.88{\pm}0.18log\;CFU/g$ during 90 days and E. coli was detected in all treatments during whole storage periods. Dioscin and allantoin contents of SB50 were virtually unchanged during the storage. Consequently, the results of this study suggest that vacuum packaged Dungkunma after blanching using 2% NaCl solution could be effective to prolong the quality of fresh-cut Dungkunma.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.37 no.3
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• pp.22-36
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• 2019

This research identified landscape characteristics of Chilitan(칠리탄) area, which had been managed by Son Giyang(1559~1617, p. Ohhan), in order to understand the political viewpoint and ideal landscapes, sought after by Confucian scholars in the 16~17th century. As the research method for the interpretation of each scene's spatial strucutres and meanings, paintings and poems in Chiltanjungsipyukgyeongdo(the Paintings of the 16 Scenes of Chiltanjung Area) were analyzed, which were followed by the on-site survey. Son lived hermit life with the nature after he decided to retire into the country for the chaotic political environment in the 4^th year of Gwanghaegun's reign. Admiring Eum Jareung(B.C. 39-41, p. Eumgwang)'s hermit life, he named a headstream to Chilitan, erected pavilion and made place for angling by the stream, as Eum did in the hermitage. However he worried the king and royal politics in spite of his hermit life, which showed his political viewpoint of Confucianism. In addition, every column of buildings in the garden was named in order to imply both thoughts of Neo-Confucianism and Idleness Naturalism, which highlight a moral training and being comfortable amid poverty and taking pleasure in and honest life style. The present landscape of wonlim could be back to 1936, where Unganru, Byeokripjae and Chiltanjung are surrounding Eupcheondang. Chines character, such as Jimamsuseok, Giam, Ohhansonsunseongjanggujiso and Jogi, are inscribed on the rocks in the landscape garden, from which placeness could be inferred. According to the record of the construction, pine, fir, paulownia, ginkgo, peach trees, bamboo and lotus were planted, and ginkgo, bamboo, crape myrtle, pine and chestnut tress are still living in the garden, which mean plants had been planted in the light of their practical values as well as symbolic meanings. The method for describing 16 scenes of Chiltanjung could be characterized to the structure of 「Place+Scene(a particural activity, event, or action), and these placeness could be analyzed by categorizing the scene to near, middle and far views. Each scene symbolically presents a hermit, noble man, Taoist ideology, homeland, or peacetime, which were adpoted to depict landscapes of Chiltanjung area as the Confucian utopia.

• Journal of Bio-Environment Control
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• v.25 no.3
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• pp.218-223
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• 2016

The calculation method of ground heat exchange in greenhouses has different ideas in each design standard, so there is a big difference in each method according to the size of greenhouses, it is necessary to establish a more accurate method that can be applied to the domestic. In order to provide basic data for the formulation of the calculation method of greenhouse heating load, we measured the soil temperature distribution and the soil heat flux in three plastic greenhouses of different size and location during the heating period. And then the calculation methods of ground heat exchange in greenhouses were reviewed. The soil temperature distributions measured in the heating greenhouse were compared with the indoor air temperature, the results showed that soil temperatures were higher than room temperature in the central part of greenhouse, and soil temperatures were lower than room temperature in the side edge of greenhouse. Therefore, it is determined that the ground heat gain in the central part of greenhouse and the perimeter heat loss in the side edge of greenhouse are occurred, there is a difference depending on the size of greenhouse. Introducing the concept of heat loss through the perimeter of building and modified to reflect the size of greenhouse, the calculation method of ground heat exchange in greenhouses is considered appropriate. It was confirmed that the floor heat loss measured by using soil heat flux sensors increased linearly in proportion to the temperature difference between indoor and outdoor. We derived the reference temperature difference which change the direction of ground heat flow and the perimeter heat loss factor from the measured heat flux results. In the heating design of domestic greenhouses, reference temperature differences are proposed to apply $12.5{\sim}15^{\circ}C$ in small greenhouses and around $10^{\circ}C$ in large greenhouses. Perimeter heat loss factors are proposed to apply $2.5{\sim}5.0W{\cdot}m^{-1}{\cdot}K^{-1}$ in small greenhouses and $7.5{\sim}10W{\cdot}m^{-1}{\cdot}K^{-1}$ in large greenhouses as design standard data.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.400-406
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• 2018

In this experiment the effect of supplemental lighting on the growth and yield of cucumber (Cucumis sativus L. 'Fresh') plants during low radiation period of winter season were investigated in glasshouses using common high-pressure sodium (HPS) lamps and newly developed plasma lighting system (PLS) lamps. Plants grown without supplemental lighting were considered as a control. Supplemental lighting was provided from November 20th, 2015 to March 15th, 2016 to ensure 14-hour photoperiod (natural+supplemental light), also lamps were operated automatically when the outside sun radiation levels were less than $100W{\cdot}m^{-2}$. Spectral analysis showed that HPS lamp had a discrete spectrum, lacked of the radiation in the 400-550 nm wave band (blue-green light), but had a high output in the orange-red region (550-650 nm). A higher red light output resulted in an increased red to far-red (R/FR) ratio in HPS lamp. PLS had a continuous spectrum and had a peak radiation in green region (490-550 nm). HPS has 12.6% lower output in photosynthetically active radiation (PAR) but 12.6% higher output in near infra-red (NIR) spectral regions compared to PLS. Both HPS and PLS lamps emitted very low levels of ultra-violet radiation (300-400 nm). Supplemental lighting both from HPS and PLS lamps increased plant height, leaf number, internode number and dry weight of cucumber plants compared to control. Photosynthetic activity of cucumber plants grown under two supplemental lighting systems was comparable. Number of fruits per cucumber plant (fruit weight per plant) in control, PLS, and HPS plots were 21.2 (2.9 kg), 38.7 (5.5 kg), and 40.4 (5.6 kg), respectively, thereby increasing yield by 1.8-1.9 times in comparison with control. An analysis of the economic feasibility of supplemental lighting in cucumber cultivation showed that considering lamp installation and electricity costs the income from supplemental lighting increased by 37% and 62% for PLS and HPS lamps, respectively.