• The Korean Journal of Ecology
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• v.7 no.3
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• pp.99-108
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• 1983

Diurnal acid fluctuation, stomatal resistance, and solar radiation with regard to the cladode orientation were investigated in Opuntia lanceolata Haw. growing at WPeolryeong-ri, Hallim-eup, Chejudo, Korea. Diurnal changes of titratable acidity showed the typical CAM pattern in all investigated cladodes. Water tissue in the cladode had the same pattern of acid fluctuation as mesophyll tissue. Stomatal resistance was low during the night, increased rapidly to be a peak right after sunrise and decreased again thereafter. The southern side of the cladode showed higher stomatal resistance than the northern side during the day time. It suggests that the stomata of the northern side opens under diffuse radiation. The amount of solar radiation varied depending upon the cladode orientation. It is thought that C4 acids move inter and intra mesophyll tissues in the cladode through the unknown pathways. RuBP carboxyulase activity in the cladode was very high at 14:00, but was not significant at 01:00. PEP-carboxylase had high activities both at 14:00 and at 01:00. The results of this study showed the possibility that O. lanceolata Haw. had the C3, C4 and CAM photosynthetic patterns under the environmental conditions at Weolryeong-ri.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.23 no.7 s.166
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• pp.1231-1237
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• 1999

Applying the conjugate contact condition, contact lines of a cylindrical worm gear has been calculated. The characteristics of tooth contact were analyzed and the pitting resistance were also assessed. It has been verified that: i) the length of contact is shortest on the 1st tooth of the front region, ii) the contact region is more narrow in the recess side than in the access side, iii) the contact region is more narrow in worm than in worm wheel. Hence, the pitting resistance is weakest in the recess side of the 1st contacting worm tooth.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.5
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• pp.14-20
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• 2020

In this study, the overall states of the airflow when a truck with or without side pairing is driven at a maximum speed of 90 km/h, regulated by domestic law, were investigated through computational fluid dynamics numerical analysis. All the tested models showed that the airflow went under the truck body; specifically, the air did not flow along the underside to the rear of the truck but through the sides of its underside. The drag with the drag coefficient at model 3 was clearly higher than those for the other two models. The results of this study could help to improve the truck performance by reducing its resistance against the air flown from it in driving itself.

• PNF and Movement
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• v.10 no.4
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• pp.71-76
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• 2012

Purpose : The purpose of this study was to examine the effects of PNF of irradiation using an indirect treatment of the stroke patient's static weight support and walking speed. Methods : Was carried out a total of nine different the PNF method of treatment for patients with left hemiplegia stroke. PNF of treatment is not in the non-paralyzed side of the trunk and upper and lower extremities by applying resistance and increased strength of the affected side. Assessment of treatment weight support both feet measured and modified using the timed up and go test were compared before and after treatment. Results : Treatment of the paralyzed side of the quadriceps and hamstring, gluteus medius muscle strength increased, and both sides of the foot body weight support improved walking speed was increased. Conclusion : Irradiation using PNF indirect treatment improves the function of the gait of stroke patients.

• The korean journal of orthodontics
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• v.27 no.2
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• pp.259-272
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• 1997

This study was performed to locate the anteroposterior position of the center of resistance of upper anterior teeth when intrusive forces are acted on them by applying segmented arch mechanics. Three-dimensional finite element model of upper six anterior teeth, periodontal ligament and alveolar bone was constructed The locations of the center of resistance were compared according to the three variables, which are number of teeth contained in anterior segment, axial inclination of anterior teeth, and degree of alveolar bone loss. The following conclusions were drawn from this study; 1. When the axial inclination and alveolar bone height were normal, the locations of center of resistance of anterior segment according to the number of teeth contained were as follows; 1). In 2 teeth segment, the center of resistance was located in the distal area of lateral incisor bracket 2) In 4 teeth segment, the center of resistance was located in the distal 2/3 of the distance between the brackets of lateral incisor and canine. 3) In 6 teeth segment, the center of resistance was located in 3mm distal of canine bracket, which is interproxirnal area. between canine and 1st premolar. 4) As the number of teeth contained in anterior segment increased, the center of resistance shifted to the distal side. 2. As the labial inclination of incisors increased, the center of resistance shifted to the distal side. 3. As the alveolar bone loss increased, the center of resistance shifted to the distal side.

• Korean Journal of Materials Research
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• v.13 no.2
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• pp.126-132
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• 2003

In order to evaluate the corrosion resistance at the anode side separator for molten carbonate fuel cell, STS316 and SACC-STS316 (chromium and aluminum were simultaneously deposited by diffusion into STS316 authentic stainless steel substrate by pack-cementation process) were applied as the separator material. In case of STS316, corrosion proceeded via three steps ; a formation step of corrosion product until stable corrosion product, a protection step against corrosion until breakaway occurs, a advance step of corrosion after breakaway. Especially, STS316 would be impossible to use the separator without suitable surface modification because of rapid corrosion rate after formation of corrosion product, occurs the severe problem on stability of cell during long-time operation. Whereas, SACC-STS316 was showed more effective corrosion resistance than the present separator, STS316 due to the intermetallic compound layer such as NiAl, Ni3Al formed on the surface of STS316 specimen. And it is anticipated that, in order to use SACC-STS316 alternative separator at the anode side, coating process, which can lead to dense coating layer, has to be developed, and by suitable pre-treatment before using it, very effective corrosion resistance will be achieved.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.369-378
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• 1996

A Lugged steel wheel was operated with two kinds of travel reduction on a sandy clay. " Small -sized transucers of the three-surfaced lug type " were installed to the wheel for the measurement of normal and tangential forces acting on a trailing lug side, lug face and a leading lug side separately . The external results acting on each surface were calculated from those measured forces. This results proved qualitatively that the relationships between external forces and lug surfaces obtained from mathematical analyses were external forces and lug surfaces obtained from mathematical analyses were correct. The traction, the motion resistance and the dynamic load were changing at the three lug surface under various operating conditions . Therefore, total analyses of three surface were indispensable to discuss the performance of the wheel lug.

• Journal of Ocean Engineering and Technology
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• v.18 no.1
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• pp.80-84
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• 2004

The initial hull form of a 3 G/T and 30 knots class coastal leisure boat is newly developed. The performances measured, resistance, trim and sinkage, are investigated in a high-speed, circulating water channel (CWC). The effect of a fin attached on the hull side is studied together. Wave patterns are observed to clarify the relationship between the resistance performance and the wave characteristics. It can be found that the fin plays a role of increasing the resistance performance above a certain velocity.

• Journal of Ocean Engineering and Technology
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• v.22 no.3
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• pp.58-63
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• 2008

A 32-ft class leisure boat was newly developed using statistical analysis of actual ships. Resistance performances were investigated by testing models in a high-speed circulating water channel, and with the CFD method. The effects of a trim tab and of a fin attached at the hull side were studied together. Wave patterns were observed to clarify the relationship between resistance performance and wave characteristics. It was found that a trim tab and a side fin play a role in increasing resistance performance within a certain velocity range.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.21-22
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• 2015

The CFT(Concrete Filled Tube) system has been developed to behave well in a structural performance such as stiffness, stress, ductility, fire resistance that is derived from its mechanical advantages of composite structure. There were number of studies about unprotected CFT columns for improving their fire resistance through reinforcing bars or plates being placed inside the steel tube. It was also known that reinforcing plates of flat type need stiffeners in a certain distance to avoid their buckling failure so it cost as much as their using consequentially. This paper is planned to test the work of beam elements attached inner side of CFT depending on its shape. More discussions on beam's design could be followed after some fire tests accordingly conducted within this project.