• Journal of the Korea institute for structural maintenance and inspection
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• v.5 no.1
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• pp.188-194
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• 2001

A reinforced concrete structure is complex structure that works as one body with bonding role of steel bar and concrete. The bonding action between steel bar and concrete makes possible the compound structure. The transmission of mutual strength of the steel bar with concrete in structure is determined by the bonding characteristic of steel bar and concrete surface. But the efficiency of bonding characteristic of steel bar is Questionable by the corrosion cause by the delay construction term, the wrong management, etc. So this study investigate bonding characteristic of reinforced concrete using pull-out test method which steel bar removed rust and the principal variables of this study are concrete compression strength and the degree of corrosion. The result showed that bonding strength tend to increase when removed rust of steel bar whereas it tend to decrease when not removed rust.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.291-294
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• 2005

In the present study, a numerical analysis was performed for interior connections of continuous flat plate to analyze the effect of column section shape on the behavioral characteristics of the connections. For the purpose, a computer program for nonlinear FE analysis was developed, and the validity was verified. Through the parametric study, the variations of shear stress distribution around the connection were investigated. According to the result of numerical analysis, the column section shape has a serious effect on the behavior of the connections. As the length of the cross section of column in the direction of lateral load increases, the effective area and the shear strength at the sides providing the torsional resistance decrease considerably. Therefore the strength model for the flat plate-column connections should be modified by considering the effect of column section shape on the behavior of the connections.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.513-516
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• 2005

Previous study on recycled aggregate(RA) has largely been limited to the manufacture of nonstructural-grade concrete due to undesirable physical properties of them such as, high water absorption leading to high water demand of concrete. The restriction seriously limits its market and consequently diminishes the use of RA as a construction material. This paper presents the mechanical properties of recycled concrete substituted by both waste foundry sand(WFS) and recycled coarse aggregate replaced with fine and coarse aggregate concurrently. The result shows that the compressive and tensile strength decrease with the increment of substitution ratio of RA and WFS while bending strength of RA concrete increase.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05a
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• pp.61-64
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• 2003

The degradation of the dielectric properties of insulating papers that were used under loaded conditions at cryogenic temperature was paid attention. Electrical and tensile stress properties of dielectric paper at cryogenic temperature have been investigated to optimum insulating design of high-Tc superconducting(HTS) cable. Tensile strength of PPLP in liquid nitrogen was high more than that of air, but tensile strain could know that decrease sharply. According as tensile strength increases, the breakdown stress of PPLP in liquid nitrogen was decreased.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.87-88
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• 2018

In this study, the tensile properties of single and hybrid fiber reinforced cement composite according to strain rate was evaluated. Experimental results, in the strain rate 10^-6/s, fiber reinforced cement composite showed improved of tensile strength and decrease of strain at peak stress as SSF volume content increased. In the strain rate 101/s, the single and hybrid reinforced cement composite's tensile properties are improved, because of the improved bond strength between the fiber and matrix. And hybrid fiber reinforced cement composite showed high energy absorption capacity, because the SSF prevented the cracking and fracture of the surrounding matrix when during the HSF pull-out.

• Journal of International Academy of Physical Therapy Research
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• v.8 no.2
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• pp.1158-1162
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• 2017

The purpose of the study was to investigate the strength of sokinetic muscle by the position of a volleyball players. Analysis and comparison of shoulder dynamic stability will be conducted according to rotational movement of the shoulder during spiking and serving amongst the various positions. Fifty professional Korean female volleyball players (age: 20~30), all different positions - attacker (left and right), center, setter, and libero were The concentric peak torque, strength ration of the internal and external rotation of the shoulder girdle for both dominant and non-dominant arms. Firstly, there were significant differences found for the strength ratio between the setter and the other positions in the dominant arm. On a second note, there was a significant decrease in shoulder dynamic stabilization for both the attacker and center in the dominant arm. However, there were no significant differences for the setter or the libero. This study suggests that the isokinetic muscle strengths of the volleyball players are different from each other.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.813-816
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• 2004

This study was performed to investigate bonding performance of epoxy resins for repairing of cracks in concrete, as a part of project to establish quality control standard for epoxy resins. In the slant shear strength test for hard and soft type epoxy, hard type was higher about 3 times than soft one. From the results, it is thought that hard type is suitable for load carrying. Injection of epoxy resin in the notch made flexural strength increase about $47\%$ over the specimen that epoxy resin is not injected. There were no differences in bonding performances with viscosity. Application of epoxy resin on the wet concrete surface made slant shear strength decrease about $46\%$, but similar performance to the case of application on the dry surface appeared by using epoxy resin for wet condition.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.285-288
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• 2006

This paper provides a method to predict the ductile capacity of reinforced concrete beams that fail in shear after flexural yielding. The proposed method takes into account shear strength deterioration in the plastic hinge region of RC beams. The shear contribution of the concrete in the plastic hinge region decreases after flexural yielding of the beam due to a decrease in the effective compressive strength of the concrete. To verify the shear strength and the corresponding ductility of the proposed method, 8 RC beams were tested under reversed cyclic loading.

• Journal of Korean Medicine Rehabilitation
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• v.28 no.4
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• pp.125-130
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• 2018

This case report was conducted to introduce the use of miniscalpel-acupuncture for the treatment of hand osteoarthritis. A-76-year old female patient who had pain on both hands due to osteoarthritis was treated with miniscalpel-acupuncture for 7 weeks. The main outcome were the Numeral Rating Scale (NRS) and the grip strength by dynamometer. After miniscalpel-acupuncture treatment, NRS was decreased and the strength of grasp was increased. The result of this study suggests that the treatment of miniscalpel-acupuncture may be effectively used to decrease pain and increase grip strength of patients who suffer from hand osteoarthritis. Further research is necessary by the reason of the limited sample size of this study.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.623-624
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• 2006

The behavior of hardmetals under cyclic loads is investigated. Unnotched specimens were employed to obtain practical information regarding fatigue in hardmetals. All the tested hardmetals exhibit an increase in the number of cycles until failure with a decrease in the maximum stress, i.e., the hardmetals exhibit a high fatigue sensitivity. The fatigue strength increases with the cobalt content. Although distinct fatigue limits, as observed in metals, cannot be observed, the calculated fatigue limit stress at $10^7$ cycles is found to be approximately 70% of the flexural strength, and the stress value exhibits a linear relationship with the flexural stress.