• Proceedings of the KSR Conference
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• 2004.06a
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• pp.1007-1013
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• 2004

A three-arch NATM tunnel with a total length of 53.5m has been constructed for a metropolitan subway station in Daejon, Korea. The tunnel, whose crown is located 22m below the ground, crosses the old Daejon station underneath. Since the tunnel comprises a very large section (10${\times}$28 m; largest in Korea), it shows complicated mechanical behaviors, especially near portal, due to its short length relative to width. As far as its construction step is concerned, the center tunnel is excavated with pre-excavated pilot tunnel, which is a unique feature of this tunnel (first in Korea) to secure safety during construction and prevent excessive settlements. The both side tunnels are then excavated along with the center tunnel. Since significant amount of settlement was predictable from the design stage, extensive monitoring was performed during construction. During excavation of the side tunnels, unexpected large settlements up to ${\~}$140mm (estimated 41.8 mm at design stage) was measured at the center tunnel. In this paper, we study the causes of this unusually large ground settlement. We believe that the extra-wide tunnel excavation increases the stress influence zone of portal in longitudinal direction and consequently add more settlements to the existing due to excavation and consolidation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1998.03a
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• pp.144-147
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• 1998

VCR is a back-up roll with a special contour which leads to the length of the contact line between back-up roll and work becones self adjustable in accordance with the width of the strip. The simulation of a finite element model and the on-line test at production mill demonstrate that the VCR roll may keep the crown of the roll gap relatively stable, and at same time, permit the rolling pressure to be adjusted over a wider range, and increase the effect of work roll bending on the roll gap. The VCR rolls have been successfully used at the first stands of two largest cold rolling mills in China, and on-line test has been done at a wide hot strip finishing train. The use of VCR roll has created favorable conditions for subsequent rolling passes and the achievement of better flatness quality.

• Mycobiology
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• v.29 no.1
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• pp.58-60
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• 2001

A destructive stem rot of wild aster(Aster koraiensis) occurred sporadically some farmers' fields in Guman-myon, Kosonggun, Kyongsangnam-do in 2000. One of the most severely infected field in Kosong showed 28.6 percent of infection rate. The fungus also caused stem or crown rot and systemic wilt or blight of the plants. White mycelium spread over stems and petioles of infected plants and sclerotia formed on the old lesions and near the soil surface. The fungus showed maximum mycelial growth around $30^{\circ}C$ and did not grow under $5^{\circ}C$ and over $45^{\circ}C$ and mycelial width were $4.3{\sim}10.2{\mu}m$. Colony was white, usually many narrow mycelial stand in the aerial mycelium and formed clamp connection. Numerous sclerotia were formed on PDA at $30^{\circ}C$. The shape sclerotia were globoid and $0.8{\sim}3.0{\times}0.9{\sim}3.4$ mm in size. The fungus was isolated repeatedly from the infected tissues and confirmed its pathogenecity to wild aster and identified as Sclerotium rolfsii. This is the first report on the stem rot of wild aster caused by S. rolfsii in Korea.

• Mycobiology
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• v.30 no.2
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• pp.102-104
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• 2002

In July 2001, a destructive stem rot of tatarian aster(Aster taturicus) was occurred sporadically in exhibition farm of Gyeongsangnam-do Agricultural Research and Extension Services, in Hamyang, Korea. The fungus also caused collar and crown rot and systemic wilt or blight of whole plant. White mycelium spread over stems and petioles of infected plants and sclerotia formed on the old lesions and near the soil surface. The fungus showed maximum mycelial growth was obtained around $30^{\circ}C$ but did not grow below $5^{\circ}C$ or above $45^{\circ}C$. The mycelial width ranges $4.2{\sim}10.4{\mu}m$. and the color is white, usually many narrow mycelial stand grow in the aerial mycelium and formed clamp connection. Numerous sclerotia were formed in artificial media like PDA at $30^{\circ}C$. The shape of sclerotia were sphere and $1.0{\sim}3.2{\mu}m$ in diameter. The fungus was isolated repeatedly from the infected, tissues and confirmed its pathogenecity to aster and identified as Sclerotium rolfsii. This is the first report that Sclerotium rolfsii causes stem rot of tatarian aster in Korea.

• Journal of Environmental Science International
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• v.25 no.10
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• pp.1407-1415
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• 2016

In this study, we investigated the relationship between noise reduction and the community structure of nine groups of typical plant communities as well as the reduction in noise at different frequencies. The semantic differential method was adopted to explore the perception of noise reduction. The results indicated that there was a significantly positive correlation between noise reduction and coverage, a significantly negative correlation between noise reduction and bifurcate height, and a negative correlation between noise reduction and bare rate. However, there was no significant correlation between noise reduction and height, diameter at breast height, or crown width. The reduction of middle-frequency noise was better than that of low- and high-frequency noise. The indicators "quiet" and "calm" showed that plant communities could reduce the noise perceived by humans. However, overly dense woodland caused nervousness, fear, depression, and other negative effects. Relatively open environments and those with large forest gaps obtained the highest evaluation.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.3 s.39
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• pp.1-9
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• 1990

Landscape plants as attenuator of vehicular noise were basically experimented with 8 kinds of trees and shrubs at the university nursery, and checked the attenuating effects by the planted distances, species and sound frequencies. The experimental results are shown and sumarized as follows ; 1. Most plants showed the considerable noise attenuating function in the sound frequencies of 63Hz and 1,000Hz. Tall trees such as Juniperus chinensis var. kaizuka and Magnolia grandiflora showed better effects than shrubs or small trees such as Gardenia jasminoides, Osmanthus fragnance, Osmanthrs heterophyllus, Rhododendron indicum, Chamaecyparis obtusa 'Tetragona Aurea' and Pinus paruiflora in 63Hz frequency, but shrubs showed better effects in 1,000Hz. 2. Trees showed 6~8dB attenuation and shrubs 4~5dB regardless an increase of distance between sound source and receiver in 63Hz. 10 meter width of tree belt could reduce 10 more dB, but 5 meter of shrub belt showed the same effect in 1,000Hz. 3. Trees having more leaves and wider crown showed constantly increase of attenuation of sound by the distance in 1,000Hz, and distinct increase of attenuation were observed in 2,000 more Hz.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.1354-1363
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• 2006

Until now, NATM(New Austrian Tunneling Method) has been increasingly developed based on concept of making use of ground as support. Also, NATM in its essence is a method of risk based on monitoring behaviour of tunnel. This Monitoring is irreplaceable for the quality construction of tunnel, and safety of tunnel itself. Pre-reinforcement ahead of a tunnel face using long steel pipes in NATM, known as the RPUM(Reinforced Protective Umbrella Method), is the auxiliary method to sustain the stability of a tunnel face and reduce the ground settlements. Since design of RPUM has been dependent on the empirical design, it is necessary to develop the improved design methods. In this study, to understand behaviour of steel pipes, it is monitored displacement of tunnel crown, axial force of rock bolt, displacement and axial stress of steel pipes. Also, in order to clarify the mechanical behaviour and RPUM effects, 3-Dimensional numerical analysis is performed that various cases of different parameter combinations including original length and repeated length of steel pipes, installation width and angle, repeated length of steel. In the results of comparison monitoring with analysis, it is suggested more economical and efficient design technique than empirical design methods.

• Journal of the Korea Fashion and Costume Design Association
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• v.10 no.2
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• pp.105-115
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• 2008

Men's outer wear, such as jackets and coats appeared since the 16th century. They have been changed from doublets, coats, justaucorps, tail-coats, frock coats and morning coats to contemporary men's suits. Since the early 17th century, sleeve patterns of men's outer jackets had been mostly two-pieces close fitted patterns. The purpose of this article is to compare sleeve patterns of various jackets, which appear in various historic costume books. Armhole measurements, sleeve head measurements, amounts of ease, armhole depths, armhole widths, crown heights, sleeve width and sleeve angle had been compared to find out the differences among patterns of different times and styles. Coming to the present, the difference between top sleeve and under sleeve became more obvious, and the sleeve angle became less curvy. Another interesting point is that there had been considerable amounts of ease, which is the difference between sleeve head measurements and corresponding armhole measurements. It is because the sleeve has been attached to the armhole not by seam but by string. It is believed that the present sleeves have more natural curve and shape compared to the past.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.4
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• pp.506-521
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• 2007

Statement of problem: The cumulative success rate of wide implant is still controversial. Some previous reports have shown high success rate, and some other reports shown high failure rate. Purpose: The aim of this study was to analyze, and compare the biomechanics in wide implant system embeded in different width of crestal bone under different occlusal forces by finite element approach. Material and methods: Three-dimensional finite element models were created based on tracing of CT image of second premolar section of mandible with one implant embedded. One standard model (6mm-crestal bone width, 4.0mm implant diameter central position) was created. Varied crestal dimension(4, 6, 8 mm), different diameter of implants(3.3, 4.0, 5.5, 6.0mm), and buccal position implant models were generated. A 100-N vertical(L1) and 30 degree oblique load from lingual(L2) and buccal(L3) direction were applied to the occlusal surface of the crown. The analysis was performed for each load by means of the ANSYS V.9.0 program. Conclusion: 1. In all cases, maximum equivalent stress that applied $30^{\circ}$ oblique load around the alveolar bone crest was larger than that of the vertical load. Especially the equivalent stress that loaded obliquely in buccal side was larger. 2. In study of implant fixture diameter, stress around alveolar bone was decreased with the increase of implant diameter. In the vertical load, as the diameter of implant increased the equivalent stress decreased, but equivalent stress increased in case of the wide implant that have a little cortical bone in the buccal side. In the lateral oblique loading condition, the diameter of implant increased the equivalent stress decreased, but in the buccal oblique load, there was not significant difference between the 5.5mm and 6.0mm as the wide diameter implant. 3. In study of alveolar bone width, equivalent stress was decreased with the increase of alveolar bone width. In the vertical and oblique loading condition, the width of alveolar bone increased 6.0mm the equivalent stress decreased. But in the oblique loading condition, there was not a difference equivalent stress at more than 6.0mm of alveolar bone width. 4. In study of insertion position of implant fixture, even though the insertion position of implant fixture move there was not a difference equivalent stress, but in the case of little cortical bone in the buccal side, value of the equivalent stress was most unfavorable. 5. In all cases, it showed high stress around the top of fixture that contact cortical bone, but there was not a portion on the bottom of fixture that concentrate highly stress and play the role of stress dispersion. These results demonstrated that obtaining the more contact from the bucco-lingual cortical bone by installing wide diameter implant plays an important role in biomechanics.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.407-414
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• 2018

This study was aimed to evaluate the effect of application method and concentration of gibberellin $A_3$ ($GA_3$) on the growth, runner production, and seedling quality of strawberry plants (Fragaria ${\times}$ ananassa Duch. cv. Maehyang) during nursery period. The mother plants of strawberry were transplanted in pot ($64{\times}27{\times}18cm$) filled with commercial growing medium on March 20, 2018. $GA_3$ concentration was applied as 0, 50, 100 or $200mg{\cdot}L^{-1}$ with spray or drench to 45 mL per plant at 4 weeks after transplanting, respectively. Nutrient solution was supplied with the EC $1.5dS{\cdot}m^{-1}$ after the transplanting and supplied 350 mL per pot twice a day (15 min per one time) after rooting. The growth characteristics of mother plants of strawberry were measured at 7 weeks after treatment, and growth characteristics of daughter plants of strawberry were measured at 10 weeks after treatment. Runner length and diameter of mother plant was the longest or thickest in the spray with $200mg{\cdot}L^{-1}$ than the other treatments, respectively. Soil-plant analysis development (SPAD) value of mother plant was the lowest in spray with $200mg{\cdot}L^{-1}$. However, leaf length, leaf width, and crown diameter showed no significant differences in all treatment among application method and concentration of $GA_3$. As the concentration of $GA_3$ increased, physiological disorder like stretchiness of crown occurred more. The physiological disorder was the most occurred in spray treatment with $200mg{\cdot}L^{-1}$, but drench treatment occurred less than spray treatment. The number of runners and daughter plants increased with increasing concentration of $GA_3$ regardless of application methods. In the growth characteristics of the daughter plants, leaf length and leaf width of first daughter plant, plant height, crown diameter, leaf area and SPAD value of second daughter plant, and plant height of third daughter plant were the significantly greatest in drench with $100mg{\cdot}L^{-1}$ treatment. This results indicate that growth and runner production of mother plants and growth of daughter plants of strawberry were the best achieved by drench application in the $100mg{\cdot}L^{-1}$ $GA_3$.