• Journal of Coastal Disaster Prevention
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• v.4 no.3
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• pp.111-118
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• 2017

In this study, pull box members were designed by finite element analysis of a steel plate covering a pull box to secure its safety on the landing pier dedicated to the large research survey ship. It was assumed that the maximum load is due to the 250 tonf class crane used for unloading work when the working environment in the upper part of the landing pier was considered. The safety of the pull box was evaluated by the comparison between the yield strength of the steel plate and the result of stress analysis on the steel plate due to the crane load. It was found that the stress at the plate from the crane load exceeded the yield strength of the steel(205MPa) when the upper part of the pull box was protected by a $1950{\times}1950mm$ steel plate cover. In order to compensate for this, a concrete filled steel tube(CFT) column with a diameter of 150 mm and a steel thickness of 10 mm was reinforced at the center of the plate, and the finite element analysis was carried out. However, the maximum stress at the steel plate was higher than the yield strength of the steel in some load cases so that it was tried to find appropriate thickness of the steel plate and diameter of the CFT columns. Finally, the analysis results showed that the safety of the pull box was secured when the thickness of the steel plate and the diameter of the CFT column were increased to 30mm and 180mm, respectively.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.521-528
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• 2003

In this study, a newly modified soil nailing technology called as the NDB(New Down and Board) soil nailing system is introduced. To improve the trafficability, workability, and economical efficiency, SMC(Sheet Molding Compound) board is adopted instead of using the concrete block facing. The SMC board has a distinct advantage of showing a fine view by directly coating with any kind of environmental photos. Composite material properties of the SMC board and cement grout are distinguished features of the NDB soil nailing system. In the present study, both laboratory tests(bending and punching failure tests) and field pull-out tests are carried out to analyze the behavior characteristics of the NDB soil nailing system, including the stress and strain distribution.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.238-239
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• 2014

It is well known that the bond characteristics of fiber govern the performance of fiber reinforced composite material. A preliminary study was carried out to investigate the pull-out behavior of amorphous and conventional single fiber in cement mortar in accordance with the JCI(Japan Concrete Institute) SF-8. The test was performed under displacement control, and results showed that the bond strength decreased with increasing fiber length. In addition, the amorphous steel fiber showed much higher pull-out load per unit weight compared to conventional steel fiber.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.651-658
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• 2002

A series of experimental study are performed to evaluate the shear strength and friction properties of fiber-mixed soil as backfill material in reinforced earth wall. In order to evaluate the properties of shear strength the big-size direct shear tests are carried out and on the friction properties, the shear friction tests and the pull-out tests are performed. In the results, when the mixed ratio of the net type fiber is 0.2%, the reinforcement effect was better than the others. Also the reinforcement effect of the net type fiber was larger than that of the line type fiber.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.435-442
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• 2002

Fluid Confirmation Tests(FCT) on 1500 ground Anchors install in weathered rock were carried out to investigate upper and lower limit of elastic elongation, frictional resistant of fixed anchor body, mobilized angle between anchor body and soil. All the measured data were analysed and compared with theoretical equations. The frictional angles of diaphragm wall and anchorage system in weathered rock showed nonlinear curve between upper and lower limit of standard elongation. The FCT results indicated that the frictional resistant angles increased with higher values of surcharge load. The quality assurance on the fixed anchor location was investigated by means of measuring elastic elongation during the FCT, and comparing these with theoretical design length, the quality of anchors in this particular site found to be above average standard. The results of this research works with provide valuable guide line on quality assurance of anchors system as well as resonable prediction of friction resistance between the fixed anchor body and the weathered rock.

• The magazine of the Korean Society for Advanced Composite Structures
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• v.3 no.1
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• pp.16-27
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• 2012

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.283-290
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• 1998

• Tribology and Lubricants
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• v.25 no.2
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• pp.86-95
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• 2009

Adhesion tests were carried out in order to investigate the effect of temperature on the adhesion behavior between a PMMA film and a fused silica lens in the micro scale. For the tests, a microtribometer system was specially designed and constructed. The pull-off forces on the PMMA film were measured under atmospheric condition as the temperature of the PMMA film was increased from 300 K to 443 K and decreased to 300 K. The contact area between the PMMA film and the lens was observed during the test. The adhesion behavior was changed with the change of the PMMA surface state as the temperature increased. In glassy state below 363 K, the pull-off force did not change with the increase of temperature. In rubbery state from 383 K to 413 K, the pull-off force increased greatly as the temperature increased. In addition, the area of contact was enlarged. In viscous state above 423 K, the fingering instability was observed in the area of contact when the PMMA film contacted with the lens. It was also found that the adhesion behavior can be varied with the thermal history of the PMMA film. The residual solvent in the PMMA film could emerge to the PMMA surface due to the heating and reduced the pull-off force.

• Advances in pediatric surgery
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• v.7 no.2
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• pp.130-136
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• 2001

The aim of this study was to evaluate the short-term outcomes of the trans anal one-stage pull-through procedure(TOP) in Hirschsprung's disease. Eight patients aged 3 weeks to 8 months with Hirschsprung's disease underwent this procedure. A rectal mucosectomy was performed from just proximal to dentate line to the level of peritoneal reflexion, where muscle layer was incised circumferentially. Rectosigmoid was mobilized out through the anus, and full-thickness frozen biopsy was taken for confirmation of ganglionic cells. After the rectal muscular cuff was divided longitudinally in the posterior aspect, aganglionic bowel was removed and ganglionic colon was anastomozed to the anus. The mean operating time was 161 minutes, and the mean hospital stay after operation was 3.8 days. Five patients had three to four bowel movement per day without other therapy at mean postoperative 39.2 days. Although long-term follow-up will be required, the TOP might be the new alternative surgical procedure for Hirschsprung's disease.

• Journal of Information Technology Applications and Management
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• v.27 no.5
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• pp.49-68
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• 2020

The Push-Pull-Mooring (PPM) model employ to explore the factors that affect the switching intention of mobile game players by analyzing the online survey data of 240 mobile game players in China. From the perspective of PPM model, Dissatisfaction with the current mobile game can promote players to leave the current mobile game, and other more attractive mobile games can pull players out of the current mobile game. As a mooring factor, habit can affect players' switching decisions. Players who have formed strong habits in current mobile games are more likely to resist or ignore the attractiveness of other mobile games and stay in the current mobile games rather than migrate to other mobile games. Another result shows that the more dissatisfied with the current mobile game, the higher the quality of alternative (relative challenge) mobile game, and the lower the investment size in the current mobile game, the more reluctant the players are to continue to maintain the relationship with the current mobile game. The higher the player's commitment to the current mobile game, the more likely it is to maintain the relationship with the current mobile game. The empirical results show that the framework of this study is highly consistent with the results of PPM model, and confirming that they can well apply to mobile game situations.