• Geomechanics and Engineering
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• v.24 no.6
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• pp.589-597
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• 2021

The present study evaluates geocell reinforced slope behavior. A three dimensional analysis is carried out to simulate soil and geocell elastoplastic behavior using the finite difference software FLAC3D. In order to investigate the geocell reinforcement effect, the geocell aperture size, thickness, geocell placement condition and soil compaction had been considered as variable parameters. Moreover, a comparison is evaluated between geocell reinforcing system and conventional planar reinforcement. The obtained results showed that the pocket size, thickness and soil compaction have considerable influence on the geocell reinforcement slope performance. Moreover, it was found that the critical sliding surface was bounded by the first geocell reinforcement and the slope stability increases, by increasing the vertical space between geocell layers. In addition, the comparison between geocell and geogrid reinforcement indicates the efficiency of using cellular honeycomb geosynthetic reinforcement.

• Journal of Korean Tunnelling and Underground Space Association
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• v.24 no.6
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• pp.699-714
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• 2022

The objective of this study is to suggest a safe and economical pillar reinforcement method when very near-twin tunnels with a minimum interval of 1 m passes through a soft zone such as weathered soil or weathered rock. A standard cross-sectional view of a two-lane road tunnel was applied to suggest a pillar reinforcement method for the very near-twin tunnels. The thickness of the pillar was 1 m. The ground condition around the tunnel was weathered soil or weathered rock. There were four reinforcement methods for pillar stability evaluation. These were rock bolt reinforcement, pre-stressed steel strand reinforcement, horizontal steel pipe grouting reinforcement, horizontal steel pipe grouting + prestressed steel strand reinforcement. When the ground condition was weathered soil, only the pillar reinforced the horizontal steel pipe grouting + prestressed steel strand did not failed. When the ground condition was weathered rock, there were no failure of the pillar reinforced the horizontal steel pipe grouting or the horizontal steel pipe grouting + prestressed steel strand. It is considered that the horizontal steel pipe grouting reinforcement played a role in increasing the stability of the upper part of the pillar by supporting the upper load applied to the upper part of the pillar.

• Journal of the Korea institute for structural maintenance and inspection
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• v.10 no.3
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• pp.211-218
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• 2006

From the development of residential flat plate system, continuously bended shear reinforcement is developed for the prevention of punching shear. To know the punching shear capacity of developed shear reinforcement in slab-column joint, structural test is performed. The testing parameters are shear reinforcement types, such as no reinforcement, bended shear reinforcement, and head stud reinforcement. To verify the lateral capacity, cyclic load is applied under the constant vertical load condition. The results of tests are compared to as global displacement, slab-column joint strength. From the test results, the resisting capacity of developed shear reinforcement system has a good performance in the story drift ratio.

• Journal of the Korean GEO-environmental Society
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• v.15 no.11
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• pp.43-51
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• 2014

In this study, a series of pullout experiments were conducted on geogrid with attached passive reinforcement with respect to silt containments. Experiments were performed on man-made sand ground containing different silt of 0 %, 17 %, 35 % under various normal stresses 30 kPa, 60 kPa, 120 kPa respectively. The pullout test results showed that passive reinforcement increased the pullout strength over all silt contained condition and showed up to 20 % increases for same soil condition. The test results converted to the coefficient of interaction of pullout test to investigate the effect of reinforcement and the case of passive reinforcement showed 0.7~1.6 distribution depend on a silt contents. Therefore it is concluded that the overall length of geogrid can be reduced under the low vertical stress conditions.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.11-12
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• 2012

This study investigates the temperature rise of reinforcement bars located in the middle of the form (for reinforcement concrete) during hot weather condition. The temperature was measured for three consecutive days before placing concrete. Test results showed that the temperature started to increase at 7:00 AM before sun rised, and peaked at around 2:00 PM. It was found that the thinner the diameter of a reinforcement bar, the higher is the speed of temperature rise and drop of the bar. The peak level of temperature for D13, D19, D25 and D32 was 54.4℃, 55.2℃, 56.4℃ and 60.2℃, respectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.121-124
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• 2005

The existing reinforcement methods of construction are the actual condition without the method of checking exact injection of adhesives clearly by the opacity of reinforcement material. In this study, in order to solve such a problem, the high strength transparent panel using a glass fiber is developed and in order to examine reinforcement effect of a panel clearly, the structure performance evaluation experiment was conducted. As a result, we knew that it can check with the naked eye the injection process of adhesives and reinforcement effect was also observable.

• International Journal of Korean Welding Society
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• v.1 no.2
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• pp.18-22
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• 2001

The stress intensity factor has been calculated theoretically for the cracked plate subjected to remote normal stress and reinforced with a plate by symmetric seam welding. The singular integral equation was derived based on displacement compatibility condition between the cracked plate and the reinforcement plate, and solved by means of Erdogan and Gupta's method. The results from the derived equation for stress intensity factor were compared with FEM solutions and seems to be reasonable. The reinforcement effect gets better as welding line is closer to the crack and the stiffness ratio of the cracked plate and the reinforcement plate becomes larger.

• Journal of Welding and Joining
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• v.16 no.1
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• pp.63-69
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• 1998

The stress intensity factor has been calculated theoretically for the cracked plate subjected to remote normal stress and reinforced with a sheet by symmetric seam welding. The singular integral equation was derived based on displacement compatibility condition between the cracked sheet and the reinforcement plate, and solved by means of Erdogran and Gupta's method. The results from the derived equation for stress intensity factor were compared with FEM solutions and seems to be reasonable. The reinforcement effect gets better as welding line is closer to the crack and the stiffness ratio of the cracked plate and the reinforcement sheet becomes larger.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.910-917
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• 2020

In fire suppression, continuous delivery of water or foam to the fire source is essential. The present study concerns fire suppression in a ship under sea condition, by introducing reinforcement learning technique to aiming of fire extinguishing nozzle, which works in a ship compartment with six degrees of freedom movement by irregular waves. The physical modeling of the water jet and compartment motion was provided using Unity 3D engine. In the reinforcement learning, the change of the nozzle angle during the scenario was set as the action, while the reward is proportional to the ratio of the water particle delivered to the fire source area. The optimal control of nozzle aiming for continuous delivery of water jet could be derived. Various algorithms of reinforcement learning were tested to select the optimal one, the proximal policy optimization.

• Journal of Acupuncture Research
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• v.20 no.6
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• pp.190-200
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• 2003

Objective: The purpose of this study is to examine influences by the order, Reduction and Reinforcement in Acupuncture on cerebral hemodynamics [regional cerebral blood flow(rCBF) and mean arterial blood pressure(MABP)] in normal rats. Methods: This experiments was to to investigate eath other changes of rCBF and MABP at Xingjian(LR2)(1st) Shaofu(HT8)(2nd) Reduction, Xingjian(LR2)(1st) Shaofu(HT8)(2nd) Reinforcement, Shaofu(HT8)(1st) Xingjian(LR2)(2st) Reduction and Shaofu(HT8)(1st) Xingjian(LR2)(2st) Reduction in Acupuncture. Results: 1. LR2(1st) HT8(2nd) Reduction in Acupuncture was decreased rCBF and MABP in compared with normal condition. 2. LR2(1st) HT8(2nd) Reinforcement in Acupuncture was significantly decreased rCBF, and was decreased MABP in compared with normal condition. 3. HT8(1st) LR2(2st) Reduction in Acupuncture was decreased rCBF during acupuncture but was recovered rCBF after with-drawing of the neddle. 4. HT8(1st) LR2(2st) Reduction in Acupuncture was decreased MABP during acupuncture and after withdrawing of the neddle. 5. HT8(1st) LR2(2st) Reinforcement in Acupuncture was significantly increased rCBF during acupuncture and 30min after withdrawing of the neddle. 6. HT8(1st) LR2(2st) Reinforcement in Acupuncture was decreased MABP during acupuncture, but was recovered MABP after withdrawing of the neddle. Conclusions: I suggested that LR2 HT8 Reduction in Acupuncture and LR2 HT8 Reinforcement in Acupuncture cause a diverse response of cerebral hemodynas.