• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.6
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• pp.496-505
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• 2020

In the previous research, the effectiveness of resonator was confirmed through the numerical analysis on two cases with the use of existing resonator at the Mukho and Imwon ports located in the eastern coast of South Korea by discussing the reduction rates of 1983 Central East Sea tsunami, and 1993 Hokkaido Southwest off tsunami, respectively. In this study, the reduction rates of tsunami height with three different resonators, Type I, II-1, and II-2, at the Samcheok port were examined respectively through the numerical analysis using COMCOT model under the same condition as the previous study. It was discussed the spatial distribution of maximum height of tsunami, change of water level, and effectiveness of resonator with the presence of new types of resonator, and change of their sizes. As a result, the effectiveness of resonator was verified through the application of new types of resonator reducing about maximum 40% of tsunami height. In order to design the optimal resonator for the variety of site condition, it is necessary to research about the various cases applying different shape, arrangement, and size of resonator as further study.

• Journal of Drive and Control
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• v.4 no.1
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• pp.16-22
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• 2007

• Journal of Drive and Control
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• v.7 no.2
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• pp.25-32
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• 2010

• Proceedings of the Korean Nuclear Society Conference
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• 2003.10a
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• pp.243.1-243.1
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• 2003

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.2
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• pp.107-112
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• 2013

In the paper, velocity controller of switching module and temperature controller for the high-voltage static var compensator are proposed. Because of the continuous increase in demand for electric power, transmission and distribution facilities of power plant are required. There is a bottleneck problem of transportation routes according to new construction and expansion of power transmission facilities. Therefore there are researches to maximize the utilization of existing facilities and to increase transmission capacity without new construction. The previous static var compensator detects voltage of input circuit of power, switches the SCR directly and generates switching noise. The proposed method increases switching velocity and decreases noise using switching control based on the voltage between both sides of SCR. Also the proposed method enhance the stability using realtime temperature control for heating of the system from increase of switching velocity. We experiment the velocity and temperature control of the proposed high-voltage static var compensator in the real environment and verify the performance of the proposed system by applying in the real field.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.323-323
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• 2011

산지가 많은 국내의 지형적인 여건은 토지의 이용에 다양한 영향을 준다. 산지주변에서는 능선을 따르거나 가로지르는 도로가 건설되고 산지계곡 하류에 발달한 선상지에는 가옥이 들어서거나 경작지로 활용되고 있다. 이러한 환경에서 우리나라는 지난 10년간 사면재해로 인한 사망자가 전체 자연재해에 27%에 달하고 이는 집중호우가 발생하는 시기에 집중되고 있어 이에 대한 연구가 필요한 실정이다. 본 연구에서는 호우 발생 시 산지하천에서 발생하는 토석류의 흐름특성을 연구하기 위해 국내 외 토석류 실험장치에 대한 조사와 토석류 실험장치를 개발하여 토석류발생 및 도달거리 예측을 위한 실험을 수행하였다. 토석류 실험장치는 수조길이 5.5m에 10-40cm의 가동폭 그리고 상 중 하류의 3단계 경사조절이 가능하며 토석류 퇴적장치를 결합하여 도달거리 및 퇴적분포를 계측할 수 있다. 토석류를 발생시키기 위해 토사공급장치 이용방법, 하상퇴적토사를 이용한 방법 등 다양한 시도를 하였다. 토석류 실험장치를 이용하여 발생시킨 토석류의 특성과 퇴적장치 에서의 도달거리를 측정하여 유량공급과의 상관관계를 분석하였다. 이러한 연구결과는 토석류 재해지도의 작성이나 토석류 해석모형의 개발에 필요한 기초자료로 활용될 수 있다.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.441-445
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• 2008

LRT is eco-friendly transportation system and can be constructed at less than half cost of subway. Therefore many local governments have planned to construct a various type of LRT and some of them were already under construction. In Para. 2 of Art. 22 of the "Enforcement Decree of Urban Railroad Act" - safety standard of urban railroad vehicle, It can't be operated if "structures and devices" don't come up to standard required to safety operation. Constructor or operator should give an order or operate according to safety standard in Art. 3 of the Safety Standard of Urban Railroad Vehicle. Safety Standard of Urban Railroad Vehicle of 2000 was reformed once to tighten fire safety standard in 2004 after subway accident in Daegue. It was entirely made for medium and large-sized electric motor car. LRT, based on driverless operation and articulated bogie, has different safety standard in signalling devices and the axle load. etc. So many institutes related LRT have required to amend. In this paper, we described features of LRT vehicle and necessity of amendment and discussed how it should be amended.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.6
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• pp.147-154
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• 2008

Experimental study has been performed in order to investigate the behavior of RC beams strengthened with externally unbonded post-tensioned CFRP (Carbon Fiber Reinforced Polymer) strips using embedded or stud-type plate anchorages. Total 10 small-scaled specimens were manufactured with the different post-tensioning level and types of mechanical anchorage as a main test parameter. A control specimen and specimens with simply bonded CFRP strips were included to compare the structural performances of each system. From the test results, it was observed that the specimens strengthened with simply bonded CFRP strips showed debonding failure below 50% of CFRP tensile strength due to premature debonding. On the other hand, all the specimens strengthened with post- tensioned unbonded CFRP strips reached the rupture strength of the CFRP strip. Also, it was observed that the specimens with stud-type anchorage have equivalent strengthening performance compared with embedded-type anchorage.

• Korean Journal of Construction Engineering and Management
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• v.9 no.1
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• pp.55-65
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• 2008

It is increasingly recognized that the construction equipment play an important role as resources in construction process. The number of registered construction equipment in korea is over 320,000 according to the statistics. It is obvious that the machine-intensive construction method achieves productivity and quality improvement as well as safety. The main objective of this paper is to propose improvement plans for construction equipment management system in terms of scope, registration, inspection, rental business, operating licenses, and etc., which are the major issues described in the Construction Equipment Management Law. In order to satisfy the objective, this research conduct survey and interview with experts, and literature review on domestic and overseas related laws and regulations. The results of the research are about 20 issues for improvement plans for the better management system, so the further in-depth study on each issue will be recommended for the practical application to the law.

• 월간 기계설비
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• s.306
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• pp.87-93
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• 2016

중소기업청은 지난 해 12월 30일 '중소기업자간 경쟁제품 지정내역 및 공사용 자재 직접구매 대상품목'을 개정하고 올해 1월 1일부터 3년(2018.12.31)간 적용에 들어갔다. 개정된 공사용 자재 직접구매 대상품목 중 그동안 대한기계설비건설협회(회장 이상일)가 지정 제외를 위해 총력을 기울였던 고무발포단열재가 기존 공사용자재 직접구매 대상품목 중에서 유일하게 제외됐다. 새로 개정된 공사용 자재 직접구매 대상품목은 고무발포단열재, 애자, 공기살균기, 플라스틱포대 등 4개 품목이 빠지고 신규 지정을 신청한 12개 품목 중 8개(커튼, 차양, 볼라드, 잡석, 데이터 포트장치, 디지털영상 정보 안내시스템, 막구조물, 포설형 탄성 포장재)만 채택돼 총 127개 품목으로 확정됐다. 고무발포단열재가 공사용 자재 직접구매 대상품목에서 제외됨으로써 앞으로 기계설비건설업계의 매출 신장과 생산성 향상에 크게 기여할 것으로 기대되고 있다.