• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.2
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• pp.84-90
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• 1986

This experiment was carried out to evaluate the effect of cutting frequency and the last cutting date on the dry matter yield, the initial characteristics of spring growth, the yield of the first crops after winter, crude protein and crude fiber yield and the correlation efficients among the above items in timothy-dominated award. Cutting frequency was scheduled by 2, 3 and 4 times a year as main plot and the last cutting date in autumm were sept. 30, Oct. 10 and Oct. 20 as subplot. Experiment was arranged as a split-plot design with three replications and was performed for 4 years from 1980 to 1983 at the alpine area. The results obtained are summarized as follows: 1. The start of spring growth was somehow early as cutting frequency increased but not significant, and was not influenced by the last cutting data. 2. The dry matter yield was decreased by cutting frequency, but was not affected by the last cutting data. 3. The dry matter yield of the first crops after winter significantly decreased by cutting frequency, but failed to show and significant differences by the last cutting date. 4. Crude protein yield was increased by cutting frequency, while dry matter percentage was decreased. Crude fiber yield did not show the same trends. 5. There was a significant positive correlation between DM yield and DM percentage and yield of the first crops after winter, and between DM percentage and yield of the first crops after winter. However, there was a significant negative correlation between crude protein yield and DM percentage and yield of the first crops after winter. 6. It may be concluded from the above results that three times as cutting frequency and Sept. 30 as the last cutting data were desirable for the DM yield, but four times as cutting frequency and Sept. 30 as the last cutting data for the crude protein yield.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.3
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• pp.206-211
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• 1984

The influence of fertilizer on the growth characteristics in Korean lawn grass was studied from June through October in a experiment. The results were as follows: 1. Maximum dry matter weight of Korean lawn grass was achieved in early in early August when it was $64.3g/m^2$ without fertilizer and $157.9g/m^2$ with fertilizer. On the other hand, the dry matter weight of whole plant including Korean lawn grass reached the maximum in late September, which was late, to some extent, compared with that if pure Korean lawn grass, presumably associated with seed maturing period of $C_4$ type plants. 2. Notable positive effect on leaf blade and non-leaf part weight in Korean lawn grass was also detected. However, the rate of dry matter occupied by non-leaf part was markedly increased by fertilizer application. 3. The dry matter portion occupied by Korean lawn grass the in total dry matter weight of whole plant was significantly decreased as time went by, particularly in case of fertilizer application. 4. Fertilizer, which might imply an increased potential of tiller numbers according to fertilizer. 5. In general, the seasonal change pattern of the rhizome of Korean lawn grass coincided with that of the aboveground organs: Its maximum dry matter weight achieved from late August to early September was $194.2g/m^2$ with nil fertilizer, and, with fertilizer, $259.7g/m^2$, of which figures were equivalent to be increased to 33.7%, compared to that with nil fertilizer. Applying fertilizer increased the weight of root: The highest values were $36.7g/m^2$ with nil fertilizer and $80.9g/m^2$ with fertilizer.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.1
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• pp.41-60
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• 1983

Experiments were conducted to study the effect of stage of maturity at harvest on the quality of silage. Herbage samples taken from the barley plant, rye plant, wheat plant, oat plant, Orchardgrass, Italian ryegrass, a mixed grass sward of Orchardgrass and Italian ryegrass and corn plant at different stages of maturity and ensiled in order to evaluate the effect of maturity on the chemical composition and feeding value as well as digestibility using sheep. Forage material were ensiled in small concrete silo. 1. The dry matter yield per 10a increased with advancing the maturity. Yield of brarley plant was 404, 635 and 900 kg at heading, milk and milk dough stage, respectively. Rye plant yield was 279, 589, 708, 10,000, 1,265, 1,376 and 1,492 kg at booting, before heading, early heading, late heading, early flowering, late flowering and after flowering stage, respectively. Italian ryegrass yield was 355, 613, 844 and 1,109 kg at vegetative, booting, heading and flowering, respectively. Orchardgrass/Italian ryegrass production was 477, 696, 891 and 1,027 kg at before was 458, 1,252, 1,534, 1,986 and 2,053 kg at tassel, early milk, yellow ripe and ripe stage, respectively. 2. Dry matter content increased with advancing maturity, but crude protein declined markedly. The NFE content decreased with advancing maturity of all the herbages except corn plant where NFE content increased, but corn plant increased. The content of crude fiber increased with advancing maturity except corn plant. The content of crude ash decreased with advancing maturity. In the rye plant, the content of neutral detergent fiber (NDF), acid detergent fiber (ADF) and cellulose increased with advancing maturity. 3. In vitro dry matter digestibilities of the rye plant was 53.6, 54.1, 50.7, 47.1, 44.9, 40.1 and 38.9% booting, before hcading, early heading, late heading, early flowering, late flowering and after flowering stage, respectively. The regression equation was $Y=56.22-0.74X+0.009X^2$ (X=cutting date from the first cut, Y=dry matter digestibilities). 4. In vitro digestible dry matter yield (kg/10a) of rye plant increased with advancing maturity, but declined from the flowering stage. The regression equation was $Y=168.88+26.09X-0.41X^2$ (X=cutting date from the first cut). 5. In vitro digestibility of dry matter in the corn plant was 69.2, 71.5, 69.8 and 69.9% at tassel, early milk, milk and yellow ripe stage, respectively. 6. The digestibility of crude protein and crude fiber of all plants decreased with advancing matuity, but NFE of the barley and corn generally increased. 7. The TDN contents on the dry matter basis decreased, but those of barley and corn silage were not different. TDN content of barley was 57.8, 57.1 and 57.9% at heading, milk and milk dough stage, respectively. That of rye silage was 50.0, 27.2 and 43.7% at early flowering, after flowering and milk stage, respectively. Italian ryegrass silage was 67.9, 63.7, and 54.9% at before heading, early heading and after heading, respectively. In case of Orchardgrass silage the TDN was 54.8, 52.9 and 46.1% at after heading, after flowering and milk, respectively. Corn shows TDN value of 59.5, 62.8 and 61.6% at milk, yellow ripe and ripe, respectively. 8. The pH value increased slightly by advancing maturity. 9. the content of organic acid decreased by advancing maturity and also increasing the DM content.

• Journal of the Korea Concrete Institute
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• v.16 no.1 s.79
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• pp.36-42
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• 2004

Although steel-reinforced concrete(SRC) is widely used in a high-rise building, a methods used to predict the column shortening of SRC structural members has many problems in applying a theoretical equation which considers only the material characteristics of reinforced concrete. In this study, the degree of accuracy of the existing method calculating the column shortening of a high-rise building is examined. For this, first, the actual measurement data are chosen about the column shortening of a high-rise building established with SRC structural members. Then the column shortening of a SRC structural member is calculated through computer program. Finally, the comparison between the measurement data and the analytical ones is executed. According to this study, it can be concluded that there is little difference between the former and the latter. Therefore, the existing method can be used to evaluate the column shortening of a high-rise building using a SRC structural members.

• Journal of Korean Association for Spatial Structures
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• v.10 no.4
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• pp.93-102
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• 2010

In this study, a smart sky-bridge composed of MR damper and FPS has been proposed and vibration control performance of a smart sky-bridge for the connected buildings was investigated. To this end, 10-story and 20-story building structures connected by a smart sky-bridge were selected as example structures and El Centro and Kobe earthquakes, which have near and far fault ground motion characteristics respectively, were used for time history analyses. In order to effectively control the smart sky-bridge, fuzzy logic controller was developed and multi-objective genetic algorithm was used to optimize fuzzy logic controllers. Based on optimization results, it has been seen that there is a trade-off between seismic responses of 10-story and 20-story buildings and a suite of Pareto optimal solutions of fuzzy logic controllers for seismic response control can be obtained by multi-objective genetic algorithm. It is shown from numerical study that seismic responses of adjacent buildings can be efficiently controlled by using a smart sky-bridge.

• Korean Journal of Medicinal Crop Science
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• v.1 no.2
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• pp.125-128
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• 1993

This study carried out to know the growth characteristics and Co-production effect of leaf, newly developed stem and fruit by different harvest times. The dry matter yield of above growth part shown the highest at mid of July. Leaf dry matter, however, shown the highest at end of June and after that decreased drastically. The dry matter yield of newly developed stem increased gradually from early stage to harvest. Fruit set number of first branch was much higher than that of main stem and 2nd branch. The more leaf and newly developed stem harvest the less fruit yield obtained. When Co-production considered by economic yield, fruit yield with three times of leaf harvest shown the best production.

• Korean Journal of Weed Science
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• v.13 no.1
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• pp.44-54
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• 1993

This experiment was conducted to understand the environmental factors affecting growth and tuber formation such as temperature, day length, tight intensity, water condition and cutting time of Eleocharis kuroguwai Ohwi. Plant height, shoot number and dry weight of E. kuroguwai were higher at high temperature, 25/$25^{\circ}C$ (day/night), while nitrogen content was higher at low temperature, 20/$15^{\circ}C$. Plant height was more affected by water temperature, while shoot number and dry weight were more affected by air temperature. Contents and absorption of nitrogen, phosphorus, and potassium in top parts of E. kuroguwai were higher under greater difference between air and water temperatures, i.e., 18/$28^{\circ}C$ and 28/$18^{\circ}C$. The number and weight of tubers were increased under greater difference between air and water temperatures, i.e, 18/$28^{\circ}C$ and 28/$18^{\circ}C$, while they were inhibited at low or high air/water temperatures (18/$18^{\circ}C$ or 28/$28^{\circ}C$). Tubers of E. kuroguwai were formed at 8-or 12-hour day length, however, no tuber was formed at l6-hour day length. Photoinductive period for tuber initiation of E. kuroguwai was between 30 and 45 days after emergence, and the induction period of short-day treatment was less than 10 days. Tuber number and weight were reduced by shading due to inhibition of the growth of top and underground parts. Number of days from planting to tuber initiation was shortned as planting time was delayed and plant height, dry weight, and tuber number were also reduced by delayed planting. Tuber number at l0 to 15cm water depth was decreased 63 to 75% as compared with 1 to 5cm water depth. Tuber number and dry weight were not affected by the size of tubers at planting. Due to the reduced growth of top and underground parts, tuber number and dry weight of E. kuroguwai were decreased by delayed shoot cutting. The critical cutting time to inhibit the growth of E. kuroguwai was about 70 days after emergence.

• Horticultural Science & Technology
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• v.28 no.5
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• pp.728-734
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• 2010

We studied the accumulation and partitioning of dry weight (DW) and nitrogen (N) in different parts of field-grown 'Fuyu' persimmon to elucidate that the foliar applications of supplemental N in June or September compared favorably with the traditional soil application in securing leaf area and fruit production. We also estimated the proportion of N permanently removed from the tree at the end of a growing season. Urea was applied either to leaves in June and/or September or to the soil in June and September for three consecutive years, and the trees were excavated in November for analyses. Total DW ranged from 4.2-4.8, 8.7-9.2, and 17.1-21.5 kg in a 4-, 5-, and 6-year-old tree, respectively, without statistical difference among the four treatments. Of the total DW, 3.3-10.2% was in shoots, 5.7-10.5% in leaves, 8.3-31.4% in aerial woods, 13.0-27.0% in root, and 28.0-59.3% in fruits. As the trees became more productive, DW proportion of fruits significantly affected that of the root: in 6-year-old trees, root DW accounted for only 10.6-15.8% of the tree total when fruit DW accounted for 50-60%. N contents ranged from 24.6-28.3, 48.3-53.5, and 98.3-122.6 g in a 4-, 5-, and 6-year-old trees, respectively, without statistical difference among the treatments. Of the total N, 6.2-11.5% was in shoots, 16.7-24.3% in leaves, 17.6-23.5% in aerial woods, 17.2-37.5% in roots, and 16.9-34.4% in fruits. As in DW, the increase in the proportion of N in fruits decreased in the root most significantly. Application methods for supplemental N did not affect the proportion of DW and N removed from the tree through abscising leaves and harvested fruits. Percentage of DW removal was 41 in 4- and 5-year-old trees, but it was 61 in more productive 6-year-old trees; that of N was 39, 43, and 49%, respectively. No significant changes in the contents of DW and N in field-grown trees, as well as their percentages removed from the tree at the end of the season, demonstrated that foliar application of supplemental N was as good as soil applications with much less N.

• The Magazine for Energy Service Companies
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• s.47
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• pp.22-25
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• 2007

경기도 시흥시 정왕동에 위치한 한국산업기술대학교가 국내대학 최초로 공학교육과 연구개발, 기숙사 기능을 혼합한 새로운 형태의 '산학협력 복합시설'을 선보였다. 기술혁신파크(TIP)가 바로 그것. 이곳은 연면적 $47,273m^2$로 대학 단일 건물로는 전국 최대 규모를 자랑한다.

• 주택과사람들
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• s.208
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• pp.68-71
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• 2007

최근 국내 설계 업체들의 해외 진출이 눈에 띄게 활발해지고 있다. 국내 설계 업체들이 드디어 해외에서도 그 실력을 당당히 인정받고 세계적인 업체들과 어깨를 나란히 하게 된 것이다. 아랍에미리트(UAE)와 베트남, 중국에 우리 건축가와 설계팀이 디자인한 건물이 들어서는 것은 자부할 만한 일임이 분명하다. 숨겨진 한류 열풍의 주역들을 만나보았다.