• Journal of Korea Foresty Energy
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• v.21 no.3
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• pp.28-33
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• 2002

This study was carried out to develop the technique for the production of high quality container seedlings of Comus controversa Hemsley. The seedlings were grown on the medium of peatmoss : perlite : vermiculite (1:1:1, v/v) in plastic net container and no-net plastic container as control for five months in the PE house. The seedlings grown in the plastic net container showed better root collar diameter growth, better development of long and fine roots, more increment of dry mass of roots and shoots than those grown in the no-net container. But the height growth of the seedlings in both container was similar. In particular the seedlings grown in plastic net container had no spiraling roots which were always observed in the control container seedlings. This result was induced by air-root pruning effect from the plastic net container.

• Journal of the Korean Institute of Educational Facilities
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• v.11 no.5
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• pp.14-23
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• 2004

Building-integrated photovoltaic(BIPV) systems can operate as a multi-functional building components, which generates electricity and serves as part of building envelope. It can be regarded as a new architectural elements, adding to the building's aesthetics. Besides of these benefits, the application of PV systems into school buildings tends to play an important role in energy education to students. In this context, this study aims to analyse the applicability of PV systems into school buildings. For an existing school building, four types of BIPV designs were developed; rooftops, wall-attached, wall-mounted with angle, and sunshading device. Based on energy modeling of those BIPV systems, the whole 60.1kWp rated PV installation is expected to yield about 65.6MWh of electricity, that is about 50% more than the annual electricity consumption of the school, 44MWh. It was also found that the applicability of the PV systems into the school building was very high, and the rooftop systems with the optimized angle was the most efficient in energy production, followed by sunshading, wall-mounted with angle and wall-attached. It concludes that school buildings have a reasonable potential to apply PV systems in the aspects of building elements and electricity production.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.63 no.3
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• pp.186-195
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• 2018

A field study was conducted over a 3-year period from 2014 to 2016 in the central plain area, Suwon, Korea, 1) to compare the biomass production between machine-transplanted and water-broadcast seeded silage rice and 2) to elucidate the growth factors that affect the difference in biomass production between the two cultivation practices. The heading date for the water-broadcast seeded silage rice was September 11-18, which was delayed by 11-17 days when compared to that for the machine-transplanted silage rice. On average, water-broadcast seeded silage rice had a shorter plant height, more panicles per area, and a greater biomass production because of the increased straw dry weight. However, the difference in dry weight of each plant organ between the two cultivation practices exhibited yearly variation. When the data were pooled across experimental years, cultivation practices, and varieties, biomass production was highly positively correlated with straw dry weight but not with panicle dry weight. When the ratio of water-broadcast seeding to machine-transplanting was analyzed, total dry weight and straw dry weight were positively associated with each other, whereas no relationship was found between total dry weight and panicle dry weight. Despite that water-broadcast seeded silage rice produced more panicles per area than machine-transplanted silage rice, the two cultivation practices had a similar dry weight per culm. Therefore, we conclude that the silage rice from the water-broadcast seeding, compared to the machine-transplanting, produced more biomass because of the combination of the increased panicle number per area and a similar dry weight per culm. These results suggest that silage rice could be produced through water-broadcast seeding to increase biomass production with low labor and cost input.

• Journal of Bio-Environment Control
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• v.21 no.3
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• pp.271-275
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• 2012

The average annual and winter ambient air temperatures in Korea have risen by $0.7^{\circ}C$ and $1.4^{\circ}C$, respectively, during the last 30 years. The continuous rise in temperature presents a challenge in growing certain horticultural crops. Chinese cabbage, one most important cool season crop, may well be used as a model to study the influence of climate change on plant growth, because it is more adversely affected by elevated temperatures than warm season crops. This study examined the influence of transplanting time, nitrogen fertilizer level and climate parameters, including air temperature and growing degree days (GDD), on the performance of a Chinese cabbage cultivar (Chunkwang) during the spring growing season to estimate crop yield under the unfavorable environmental conditions. The chinese cabbage plants were transplanted from Apr. 8 to May 13, 2011 when 3~4 leaves were occurred, at internals of 7 days and cultivated with 3 levels of nitrogen fertilization. The data from plants transplanted on Apr. 22 and 29, 2012 were used for the prediction of yield as affected by planting date and nitrogen fertilization for spring production. In our study, plant dry weight was higher when the seedlings were transplanted on 15th (168 g) than on 22nd (139 g) of April. There was no significant difference in the yield when plants were grown with different levels of nitrogen fertilizer. The values of correlation coefficient ($R^2$) between GDD and number of leaves, and between GDD and dry weight of the above-ground plant parts were 0.9818 and 0.9584, respectively. Nitrogen fertilizer did not provide a good correlation with the plant growth. Results of this study suggest that the GDD values can be used as a good indicator in predicting the top biomass yield of Chinese cabbage.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.598-608
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• 2011

The purpose of this study was to examine potential effects of shading and fertilizing treatment - two basic applicable factors in production of 1-year-old container seedling - on growth and seedling quality of Quercus myrsinaefolia, one of evergreen tree species in warm temperate zone of Korean. Every experimental process was conducted in a facility that consisted of compartments under the lighting control with full sunlight and shading (35%, 55% and 75% of full sunlight). Based on fertilizing treatment, this study made an experiment in 4 groups of container seedling: control (non-treated seedlings) and 1000, 2000, 3000 ppm group (3 groups with different concentrations of water-soluble fertilizer (N:P:K=19:19:19, v/v). Seedlings under 55% shading with 2000 ppm concentration showed the highest height (totaling 21.1 cm), and under 35% shading with 2000 ppm concentration showed the highest root collar diameter growth (totaling 3.96 mm) among others. All three fertilizing groups except control showed H/D ratio ranging from 4.27 to 5.26 regardless of fertilizer concentration under 35% and 55% shading where container seedlings showed a tendency toward excellent growth of height and root collar diameter. Overall, 2000 ppm group under 55% shading showed highest dry mass production of leaves (1,292 g) among others, while 2000 ppm group under 35% shading showed highest dry mass production of shoots and roots (0.592 g and 0.998 g, respectively) among others. Also, it was found that 2000 ppm group under 35% shading showed the highest dry mass production of whole seedling, which was followed by 2000 ppm group under 55% shading and 3000 ppm group under 35% shading, respectively. According to analysis on LWR of Quercus myrsinaefolia depending on shading and fertilizing treatment, it was found that 3000 ppm group under 75% shading showed highest LWR level among others, whereas every fertilized group showed lower RWR level than control without fertilizing regardless of shading levels. In general, all fertilized groups under 55% shading had relatively high quality index (QI), and 2000 ppm group under 35% shading had highest QI among others. Based on the findings of this study, it is concluded that shading level ranging from 35 to 55% and fertilizing concentration of 2,000 ppm are suitable for producing 1-year-old container seedlings of Quercus myrsinaefolia with excellent growth and high quality index.

• Korean Journal of Medicinal Crop Science
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• v.7 no.2
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• pp.115-120
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• 1999

This study was carried out to compare the essential oil and its composition, and estragol content at different growth stages in the local collections of A. rugosa. Estragol was the major constituent in essential oil of all collections tested. Estragol content in essential oil was $82.3{\sim}89.1%$ in leaves, $81.1{\sim}89.2%$ in inflorescence, $72.0{\sim}45.2%$ in stem and there was no significant difference among nine local colletions. At full bloom stage, essential oil content was significantly higher than other growth stages and the highest content of estragol in essential oil was appeared at this stage. Especially, the content of essential oil in the inflorescence of Mokpo collection was 3.3%, which was the highest among the collections. Mokpo and Jindo collections produced much more essential oil and estragol than the other collections both at full bloom and ripening stages.

• Journal of the Korean Solar Energy Society
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• v.35 no.2
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• pp.93-101
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• 2015

Zero energy building is a self sufficient building that minimizes energy consumption through passive elements such as insulation, high performance window system and installing of high efficiency HVAC system and uses renewable energy sources. The Korea Government has been strengthening the building energy efficiency standard and code for zero energy building. The building energy performance is determined by the performance of building envelope. Therefore it is important to optimize facade design such as insulation, window properties and shading, that affect the heating and cooling loads. In particular, shading devices are necessary to reduce the cooling load in summer season. Meanwhile, BIPV shading system functions as a renewable energy technology applied in solar control facade system to reduce cooling load and produce electricity simultaneously. Therefore, when installing the BIPV shading system, the length of shadings and angle that affect the electricity production must be considered. This study focused on the facade design applied with BIPV shading system for maximizing energy saving of the selected standard building. The impact of changing insulation on roof and walls, window properties and length of BIPV shading device on energy performance of the building were investigated. In conclusion, energy consumption and electricity production were analyzed based on building energy simulations using energyplus 8.1 building simulation program and jEPlus+EA optimization tool.

• Journal of Digital Convergence
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• v.20 no.2
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• pp.277-287
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• 2022

ZEB is a building that increases the energy independence of the building itself, and new and renewable elements that can produce energy are essential, and BIPV is the most notable technology. In ZEB's design, BIPV should be planned early in the design, but BIPV plans are insufficient in the early stages. Therefore, this study derived elements for theoretical consideration of BIM and ZEB and analysis of ZEB independence rate based on BIM, a convergence design technology, and analyzed BIPV energy production and building energy consumption. Finally, by calculating the energy independence rate and reviewing the rating criteria in the project model, a basic research method for calculating the energy independence rate of ZEB at the beginning of the design was presented. Through this, it is expected that design productivity can be improved by supporting the decision of ZEB subjects.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.33-38
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• 2009

Effects of dry matter intake restriction to the level of recommend by NRC (2001) on intake balance of dry matter and nutrients in Holstein lactating cow were evaluated. 24 lactating cows were divided into two groups and individually fed one of the TMR offered as ad libitum (control) and restricted amount (treatment) as recommended by NRC (2001). Milk yield including 4% FCM and FPCM were showed higher tendency in treatment group then those of control group. Also, intakes of dry matter, net energy and metabolizable protein were tended to be higher in treatment group then control group. Actual dry matter and net energy intakes in control group were higher (p<0.001) then those of recommended amount by NRC (2001), whereas no significant differences in treatment group. The estimated $NE_L$ allowable milk yield were lower (p<0.001) in both control and treatment group than those of recommended by NRC (2001). It was concluded that to allow ad libitum feeding of diet containing high levels of concentrate to the lactating cows might decrease the efficiency of feed nutrients and hence result in no positive effect on productivity of milk.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.28-33
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• 1989

This study was examined for the effect of tuber size, bud and tuber removal, and tuber cutting on growth of Eleockaris kuroguwai Ohwi. Elongation of plumule and radicle, and the weights of tuber, rhizome and shoot were increased as tuber size is large. The weights of shoot and tuber reduced by bud planting without tuber at 15 days after budding, however number of tubers were increased compared with normal tuber. When cross-cutting tubers were seeded, the weights of shoot, rhizome and tuber were produced as 84%, 85%, 71%, respectively compared with normal tuber, and the number of tubers was not influenced. The weights of tuber, rhizome and shoot were lowed as the bud removal, and there were a great number of tubers at bud removal of 15 days after budding. Tuber of E. k, contained as nonfibrous 78.9gr, phosphorous 77mg, iron 16.8mg, niacin 1.3mg per 100gr edble portion. The positive correlations were observed between shoot weight and tuber weight, and number of tubers.