• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6C
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• pp.377-384
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• 2006

Theoretical and experimental study of the unconfined penetration (UP) test was conducted to suggest a new test method (referred to as IUP, Improved Unconfined Penetration) for determination of the tensile strength of compacted sand-bentonite mixtures. The tensile strength of compacted mixtures can be calculated from limit analysis based on the theory of perfect plasticity. The measurement errors in new test method were reduced by improving the UP device. Preliminary experiment results indicate that the tensile strength increases with increasing the disk size, loading rate and pH level. In addition, the disk diameter with 25.4 mm and the loading rate with 0.5%/min~1%/min are most suitable condition for the IUP test. The reliability of IPU test was verified by through the fact that good agreement between the IUP and conventional split tensile test results is observed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4C
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• pp.221-230
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• 2008

The George Massey immersed tunnel passes the Fraser River near Vancouver, Western Canada. The tunnel was founded on sandy soils and its behavior during earthquake was analyzed by an effective stress constitutive model called UBCSAND. This model is able to calculate pore pressure rise and resulting tunnel movements due to cyclic loading. Centrifuge tests conducted at Rensselaer Polytechnic Institute (RPI) were used to verify the model performance. The centrifuge tests consisted of 2 models: Model 1 was designed for an original ground condition, Model 2 for a ground improvement by densification. In Model 1, large deformation of the tunnel was observed due to liquefaction of surrounding soil. Because of the densified zones around the tunnel the vertical and horizontal displacements of the tunnel in Model 2 was 50% less than Model 1. Measured excess pore pressures, accelerations, and displacements from centrifuge tests were in close agreement with the predictions of UBCSAND model. Therefore, the model can be used to predict seismic behavior of immersed tunnels on sandy soils and optimize liquefaction remediation methods.

• Journal of Korea Foundry Society
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• v.18 no.5
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• pp.498-505
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• 1998

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.10
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• pp.1286-1293
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• 1995

Modified equivalent lumped element model for square spiral inductors have been derived. This model shows more accurate analysis performance than conventional models, and gives reliable design parameters. And this model is made through comparison among distributed multiple coupled line, numerical analysis and experimental data.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.32 no.9
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• pp.32-37
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• 2003

다양한 국가의 많은 지하철 중에서 테헤란은 기후와 문화경제 조건이 국내와는 대단히 상이하고 유럽 스타일의 설계를 적용하고 있어 차후 국내 지하철의 시설개량이나 2기 지하철에 이은 3기 지하철의 계획에 비교 검토 자료중의 하나로서 테헤란 지하철은 우리와는 사뭇 다른 설비와 구조를 가지고 있어 여기에 소개 하고자 한다.

• Journal of Korea Foundry Society
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• v.18 no.6
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• pp.604-612
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• 1998

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2009.10a
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• pp.160-163
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• 2009

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 1992.08a
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• pp.39-53
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• 1992

세계경제의 성장과 더불어 꾸준히 증가하는 해상물동량을 원활히 처리하기 위하여 정부에서는 항만시설 확충사업과 기존시설의 개량사업을 지속적으로 추진하고 있으나 국가재정의 한계로 항만시설에 대한 투자가 미흡하여 만성적인 하역능력 부족현상이 해소되지 못하고 있는 실정이다.(중략)

• Magazine of the Korea Institute for Structural Maintenance and Inspection
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• v.18 no.3
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• pp.57-61
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• 2014

• Ecology and Resilient Infrastructure
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• v.4 no.3
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• pp.180-185
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• 2017

Restoration of min-impacted arable land is often performed through stabilization of trace elements by amendment treatment combined with (clean) soil covering on the surface. Recently, soil loss problem from sloping remediated agricultural lands has risen as an emerging concern. In this study, efficacy of aggregation formation was assessed by single and binary treatments of four potential amendments (bentonite, lime, organic matter, and steel slag) applied on three cover soils having different clay contents (9.4, 14.7, and 21.2% for A, B, and C soils respectively). In results of single treatments, 5% organic matter for A soil and 5% lime for B and C soils were found most effective for the aggregation formation compared to the respective controls (without amendments). Among nine binary treatments, 3% organic matter + 1% lime for A soil and 1% organic matter + 3% lime for both B and C soils led to the highest formation of aggregation (30.4, 25.0, and 36.5% for A, B, and C soils). For a site-application, the soil erodibility difference between the cover soils (0.045, 0.051, and 0.054 for A, B, and C soils, respectively) and the national average of arable land (0.032) was assumed to be compensated by amendment addition, which is equivalent to 29.1% aggregation formation. To achieve the aggregation goal, 5% lime for A and B soils and 3% lime for C soil were best in the consideration of benefit/cost, thereby effectively and economically reducing soil loss from sloping remediation site. Soil alkalinity induced by lime treatment was not considered in this work.