• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.2
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• pp.1-22
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• 2022

The modification effects of street trees on outdoor thermal comfort in summertime according to tree planting types and road direction were analyzed using a computer simulation program, ENVI-met. With trees, the air temperature and wind speed decreased, and the relative humidity increased. In the case of mean radiant temperature (T_mrt) and human thermal sensation, physiological equivalent temperature (PET) and universal thermal climate index (UTCI), there was a decrease during the daytime. The greatest change among the meteorological factors by trees happened in Tmrt, and PET and UTCI showed similar patterns with T_mrt·The most effective tree planting type on thermal comfort modification was low tree height, wide tree crown, high leaf area index, and narrow planting interval (LWDN). T_mrt, PET and UTCI showed a large difference depending on shadow patterns of buildings and trees according to solar altitude and azimuth angles, and building locations. When the building shade areas increased, the thermal modification effect by trees decreased. In particular, results on the east and west sidewalks showed a large deviation over time. When applying the LWDN, the northwest, west and southwest sidewalks showed a significant reduction of 8.6-12.3℃ PET and 4.2-4.5℃ UTCI at 10:00, and the northeast, east and southeast sidewalks showed 8.1-11.8℃ PET and 4.4-5.0℃ UTCI at 16:00. On the other hand, when the least effective type (high tree height, narrow tree crown, low leaf area index, and wide planting interval) was applied, the maximum reduction was up to 1.8℃ PET and 0.9℃ UTCI on the eastern sidewalks, and up to 3.0℃ PET and 0.9℃ UTCI on the western ones. In addition, the difference in modification effects on T_mrt, PET and UTCI between the tree planting types was not significant when the tree effects were reduced by the effects of buildings. These results can be used as basic data to make the most appropriate street tree planting model for thermal comfort improvement in urban areas in summer.

• Journal of Environmental Impact Assessment
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• v.30 no.2
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• pp.105-116
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• 2021

In the city of high population density crowded with buildings, Urban Heat Island (UHI) is intensified, and the city is vulnerable to thermal comfort. The maintenance of vacant land in downtown is treated as a factor that undermines the residential environment, spoils the urban landscape, and decreases the economic vitality of the whole region. Therefore, this study compared the effects on microclimate in the surrounding area according to the development scenarios targeting the vacant land in Songhyeon-dong, Jongno-gu, Seoul. The status quo, green oriented, building oriented and green-building mediation scenarios were established and ENVI-met was used to compare and analyze the impact of changes in wind speed, air temperature and mean radiant temperature (MRT) within 1 km of the target and the target site. The result of inside and 1 km radius the targeted area showed that the seasonal average temperature decreased and the wind speed increased when the green oriented scenario was compared with the current state one. It was expected that the temperature lowered to -0.73 ℃ or increased to 1.5 ℃ in summer, and the wind speed was affected up to 210 meters depending on the scenario. And it was revealed that green area inside the site generally affects inside area, but the layout and size of the buildings affect either internal and external area. This study is expected to help as a decision-making support tool for developing Songhyeon-dong area and to be used to reflect the part related to microclimate on the future environmental effects evaluation system.

• Journal of the Korea Convergence Society
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• v.11 no.12
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• pp.97-103
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• 2020

This study sets the solar power system installed and applied to the vertical side wall among the photovoltaic systems in the building as the scope of the research. The theoretical background was considered through literature research as a research method, and the current status, trends and characteristics of solar generator design installed and applied to domestic and foreign vertical side walls were then investigated and analyzed cases. As a result, the importance and necessity of photovoltaic generators, potential for power generation and growth were identified, and positive factors and directions were found for improving aestheticity. Based on this point, we would like to propose expected effects that can be applied to photovoltaic system design installed and applied to vertical side walls in the future, and confirm the direction and significance of the improvement of aesthetic quality of the proposal for development of thin film solar cell design technology using green facade design.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.4
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• pp.335-340
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• 1989

In order to find out the optimum harvest (clipping) date combined with sowing date on yield and nutrient Quality of forage rape which is suitable at the southern part of Korea, Velox, introduced variety was grown from Sep. 1987 to May 1988 at Sunchon National University, and yield and nutrient Quality of plant were observed. As harvest date and sowing date were delayed, the plant length was longest, number of branch and leaves per main stem were increased in the time of full bloom clipping and Sep. 24 sowing but stem diameter was thickest in the early sowing. Fresh yield was heaviest in the time of flowering clipping and Sep. 24 sowing but the most dry matter yield was heaviest in the time of full bloom clipping and Sep. 24 sowing. Content of crude protein was highest and that of crude fiber such as NDF, ADF, hemicellulose, cellulose and lignin were lowest in the late time of clipping and sowing. Further more IVDMD was high and dry matter yield and digestible dry matter yield were highest in the time of flowering clipping and Sep. 24 sowing. Judging from the results reported above, at optimum harvest (clipping) date combined with sowing date for yield and nutrient Quality of forage rape seemed to be the time of flowering clipping and Sep. 24 sowing.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.30 no.3
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• pp.277-286
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• 1985

From a series of studies conducted on the local maize lines at the Agr. College of the Chungnam National Univ., a few maize lines with many tillers and ears per plant were identified and tentatively named as MET. The purpose of the study was to evaluate the MET lines, which were selfed for five generations, for silage purpose under the different plant densities. A hybrid, Suwon #19 and a synthetic variety, Puyo #3${\times}$#2, were included for comparison. Plant height at harvesting times showed no significant varietal differences. However, the MET lines were very slow in early plant growth compared to the hybrid or synthetic variety, probably due to inbreeding depression of the MET lines. Total fresh weight at the harvesting times was highest in the MET 1 line. The MET 1 line was about 2,000 kgr. per 10a. higher than the hybrid at the harvesting time. The highest fresh weight was obtained when grown under the plant density of 60 ${\times}$ 20cm. Total dry weight per unit area showed the same tendency as the fresh weight. Total dry weight of MET 1 line was about 2.4 tons per 10a., which was about 10% higher than the hybrid, Suwon #19. As the fresh weight, the total dry weight was also highest in the plant density of 60 ${\times}$ 20cm. The grain yield per 10 are of MET 1 was comparable to the grain yield of the hybrid, especially in the low plant density, 60 ${\times}$ 40cm. The average number of effective tillers of MET lines were 4.5, while the mean tiller number of the hybrid or synthetic variety were none. However, the lodging was one of the problem for growing MET lines. The 100 kernel weight of MET lines was about 9 gr., while the 100 kernel weight of the hybrid or synthetic variety was about 30 grm.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.4
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• pp.317-324
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• 1999

This study was conducted to evaluate the dry matter yield and quality of mixture swards associated with Festulolium braunii(Festuca pratensis Huds. ${\times}$ Lolium multiflorum Lam.). The experiment was arranged in a randomized block design with four mixture types: A(control); orchardgrass(seeding rate 60%) + tall fescue 20% + Kentucky bluegrass 10% + white clover 10%, B; orchardgrass 60% + tall fescue 20% + Festulolium braunii 10% + white clover 10%, C; orchardgrass 60% + Festulolium braunii 20% + Kentucky bluegrass 10% + white clover 10%, and D; orchardgrass 30% + Festulolium braunii 30% + red clover 40%. This study was carried out from Sept. 1996 to Dec. 1998 at Chungnam National University. The DM yield of D mixture type was higher than that of other mixture types(P<0.05). Compared with A(control) mixture type, the DM yield of the B mixture type which substitutes Kentucky bluegrass with Festulolium braunii was higher, but the C mixture type which substitutes tall fescue with Festulolium braunii was lower than that of A(control) mixture type. The content of CP, NDF, ADF, hemi-cellulose and cellulose among mixture types shows no significant differdence. Howerever, the DMD was not significantly different among mixture types in 1997, but the DMD of C and D mixture type were significantly higher than those of other mixture types in 1998(P<0.05). On the otherhand, the yield of CP and DDM in D mixture types was higher than those of the other mixture types(P<0.05). In botanical composition, the Festulolium braunii percentage of B, C and D mixture type with mixed Festulolium braunii wasd highly maintained, especially D mixture type was ranging from 40% to 60% in experimental periods. Following the above result, It is the most favorable mixture method for Festulolium braunii to make use of top grass like orchardgrass + red clover. It is also recommened to substitute bottom grass like Kentucky bluegrass with Festulolium braunii rather than with tall fescue in A(control) mixture type.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.3
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• pp.233-240
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• 1999

Understanding of the relationships between seeding rate and planting date is important for production of spring oats during the fall season. Therefore, this experiment was conducted to investigate seeding rate and planting date effects on forage performance and quality of spring oats(Avena sativa L.) at Suweon in 1997. The experiment was arranged in a split plot design with three replications. The main plots consisted of different seeding rates such as 150, 200, and 250kg/ha. The subplots consisted of different planting dates of spring oats such as 15, 22, and 29 August and 5 September. Dry matter content of oats was significantly decreased(P<0.01) as the planting date was delayed except the planting date of 5 September(24.8%). Dry matter content of forage oats planted on 15, 22, and 29 August was 23.0, 21.5, and 20.5%, respectively. A seeding $rate\;{\times}\;planting$ date interaction for dry matter content was highly significant(P<0.01). Crude protein content of oats was significantly increased(P<0.01) from 15.6 to 27.9% as the planting was delayed, while a significant seeding $rate\;{\times}\;planting$ date interaction for crude protein content of oats was observed. Acid detergent fiber(ADF) and neutral detergent fiber(NDF) contents of oats increased with early planting(P<0.01), but there was no significant difference among the seeding rates. ln vitro dry matter digestibility(IVDMD) of oats was significantly increased(P<0.01) as the seeding rate was increased together with late planting. Average dry matter yield of oats decreased(P<0.01) from 2,647 to 615kg/ha as the planting was delayed, but there was no significant difference among the seeding rates. A seeding $rate\;{\times}\;planting$ date interaction was observed for average dry matter yield of oats that the seeding rate increase in this experiment showed better at early planting dates. Crude protein yield of oats increased from 171 to 410kg/ha as the planting was delayed, and a significant increases(P<0.01) for crude protein yield was found among the seeding rates. ln vitro digestible dry matter(IVDDM) yield of oats decreased(P<0.01) as the planting was delayed, but there was no significant difference among the seeding rates. A significant seeding $rate\;{\times}\;planting$ date interaction for lVDDM of oats was found. The results of this study indicate that both the seeding rate of 200kg/ha and early planting before 29 August would be recommendable for forage yield and quality of oats in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.21 no.3
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• pp.115-122
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• 2001

The purpose of this study was to suggest the possibility of utilizing the wildflower pasture as the livestock herbage sources as well as promoting the public interests. Not only dry matter (DM) yield and soil properties of pastures were observed, but also chemical composition of herbages was analyzed. The experimental design includes four treatments: Conventional pasture(COP, forage 6 species), Bottomgrass pasture(BOP, turf grass 6 species), Native wildflower pasture(NWP, turf grass 6 species + native wildflower 11 species) and Introduced wildflower pasture(IWP, turf grass 6 species + introduced wildflower 9 species). The field trials were carried out on the experimental pasture plots at Chungnam National University throughout from 1997 to 2000. The results obtained are as follows : 1. As wildflower pasture was composed of turf grasses and wildflowers, the yearly mean of DM yield in the wildflower pastures (NWP 6,688kg/ha and IWP 7,240kg/ha) was lower than that of COP(8,592kg/ha) or BOP(7,264kg/ha)(p<0.05). This result indicated that the forage productivity of wildflower pasture for livestock is low. 2. The nutritive quality of herbages from wildflower pasture tended to be slightly low compared to that of COP and BOP. On the other hand, compared with IWP, the content of CP, NDF and lignin of herbages from NWP were lower than those from IWP, while IVDMD was higher(p<0.05). 3. The pH and the content of exchangeable Ca in NWP and IWP soils were tended to be low compared to those of COP in changes of soil properties after 3-years experimental trials, while the contents of organic matter, nitrogen, available phosphate, Mg and K were slightly improved. In conclusion, even though DM yield seem to be lower in wildflower pasture than those of COP, and the nutritive quality of herbages from wildflower pasture tended to be slightly low compared to that of COP and BOP. but, possibility of utilizing herbages from wildflower pasture for livestock was to some extent expected. In addition. compared to COP, wildflower pastures improved the property of soil. Thus, although wildflower pasture was not enough for livestock as a herbage, wildflower pasture has enough possibility for promoting the public interest.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.2
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• pp.53-60
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• 2019

This study was carried out from 2015 to 2016 to identify the suitable sowing and harvesting dates of summer crops in the mountain of Yeongnam, South Korea. The experimental design consisted of the different sowing and harvesting dates as follows: corn hybrid (Z. mays, Kwangpyeongok) of sowing (May 8, 19, and 27) and harvesting (August 10, 20, and 30); sorghum${\times}$sorghum hybrid (Sorghum bicolor ${\times}$ Sorghum bicolor, SS405) of sowing (May 27, June 19 and June 27) and harvesting (August 10, 20, and 30). In corn hybrid, ear rate and dry matter (DM) yield decreased (p<0.05) with the postponement of sowing date. Otherwise, ear rate and DM yield increased (p<0.05) with the postponement of harvesting date. Crude protein content decreased (p<0.05) with the postponement of sowing date, but neutral detergent fiber content increased (p<0.05). In sorghum${\times}$sorghum hybrid, plant length and DM yield with the postponement of harvesting date increased (p<0.05), while crude protein content with the postponement of harvesting date decreased (p<0.05). This study concluded that sowing corn hybrid in early May and sorghum${\times}$sorghum hybrid in early June then harvest in the middle of August was recommend to increase dry matter yield and feed value.

• Journal of Korean Physical Therapy Science
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• v.3 no.2
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• pp.989-995
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• 1996

This study was conducted to investigate variation of cardiopulmonary function by use of building stairs, a questionnair survey and measurement was carried out for 50 students of department of physical therapy Andong Junior College from 20th September to 3rd October, 1995. The result were as follows: The average systolic blood pressure(SBP) of stability for 50 college students who were measured was 121.3 mmHg, the average diastolic blood pressure(DBP) of stability was 78.5 mmHg, the average pulse frequency of stability was 71.8(frequency/min), the average breathing frequency of stability was 20.4(frequency/min), and the body temperature of stability was $36.8^{\circ}C$. SBP among the second, third, and fourth floors was 129.0 mmHg, 127.0 mmHg, and, 132.0 mmHg (p=0.1919), DBP was 80.1 mmHg, 76.5 mmHg, and, 82.0 mmHg (p=0.4229), the pulse frequency was 74.0, 73.1, and 74.0(frequency/min). The breathing frequency among the second, third, and fourth floors was statistically gradually increased according to 21.4, 23.1 and 24.6(frequency/min)(p=0.0071). The body temperature among the second, third, and fourth floors was statistically less and less decreased according to $36.8^{\circ}C,\;36.6^{\circ}C$ and $36.5^{\circ}C$(p=0.0040). It was revealed by this study, the breathing frequency among the second, third, and fourth floors was statistically significant increased, the body temperature was statistically significant decreased.