• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1436-1441
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• 2004

Achieving the maximum blasting efficiency with minimum abrasive consumption is a critical concern in surface preparation stage of shipbuilding and offshore industry. Increasing the abrasive flow rate beyond the optimum point results in a major reduction in productivity even though the amount of abrasive used is larger. So, this study is intend to find out the optimum abrasive-to-air mixing ratio which can make a significant improvement in blasting efficiency and remarkably reduce the amount of abrasive used. From the test results, it can be identified that as the abrasive feeding rate is increased linearly, blasting efficiency is increased to a maximum point and then gradually decreased in the form of a bell-shaped.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2010.04a
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• pp.142-145
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• 2010

• Proceedings of the Korean Geotechical Society Conference
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• 2006.10a
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• pp.153-160
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• 2006

Tunnel type spillway is rarely constructed in worldwide, and designed secondary in Korea. In this paper we pronounce a case study of tunnel type spillway design. We firstly considered lining concrete abrasiveness and cavitations for tunnel safety. This paper describes the design of tunnel type spillway section, excavation method, blasting, support and concrete lining.

• Tunnel and Underground Space
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• v.16 no.5 s.64
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• pp.377-386
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• 2006

In generally blasting pattern design is carried out in-situ borehole blasting test and its analysis. We added the 3D numerical analysis for blast induced vibrations. This paper is case study of 3D numerical analysis in which considered blast induced vibration affected across buildings, and then we design the blasting pattern of tunnel excavation.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.3
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• pp.1-11
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• 2007

The purpose of this study is to predict promising Location Based Services under an ubiquitous environment based on their technical characteristics, which is strongly required in rapidly changing circumstances with ubiquitous computing and Broadband Convergence Network (BcN). To begin with, this study proposes a classification scheme of ubiquitous services and defines five technology factors required for ubiquitous services. Next, this study collects a number of ubiquitous services from previous researches and classified them according to the classification scheme of ubiquitous services. And then, technical importance of the collected ubiquitous services are evaluated in terms of technology factors by using service-technology metrics. Finally, a set of important Location Based Services under ubiquitous environments and the correlations between technology factors are identified by using the evaluation results.

• Journal of the Korean Chemical Society
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• v.42 no.4
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• pp.411-415
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• 1998

In the present study, we were evaluated cytotoxic effects of epigallocatechin gallate in human skin melanoma cells such as HTB-69. The light microscopic study showed morphological changes of the treated cells. Disruptions in cell organelles were determined by colorimetric methods; 3-(4,5-dimethyl thiazol-2-yl)-2,5diphenyl-2H-tetrazolium bromide (MTT) assay, neutral red (NR) assay and sulforhodamine B protein (SRB) assay. These results suggest that epigallocatechin gallate retains a potential antitumor activity.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.3
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• pp.204-210
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• 2000

This paper proposes a new reactive-power compensator composed of a soft-switching current-source inverter. The compensator consists of 3-Phase IGBT bridge, dc reactor, and a resonant circuit. The resonant circuit offers the IGBT bridge to have PWM operation with minimal switching losses. A theoretical analysis and computer simulation with Is-Spice were done to verify the operation of the proposed system. Also a acaled-model of the system was built and tested for verifying the feasibility of proposed system.

• 대한예방의학회:학술대회논문집
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• 1997.10b
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• pp.251-252
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• 1997

• 한국ITS학회:학술대회논문집
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• 2004.11a
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• pp.224-227
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• 2004

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.125-125
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• 2017

우리나라는 도시의 집중화 현상이 점차 심화되고 있으며, 기후변화에 따른 기상 수문학적 영향으로 인해 집중호우, 홍수 등 수재해 증가, 가뭄으로 인한 물 부족 및 물 자급율 저하로 도시의 수원 다원화 및 재활용에 대한 관심이 증가하고 있다. 최근들어 이러한 문제점을 인식하고 각 지자체 별 도시의 건전한 물순환을 회복시키기 위한 노력이 이루어지고 있다. 서울시는 서울특별시 빗물관리 기본계획을 수립하였으며, 수원시는 2013년부터 레인시티를 본격적으로 도입하였고, 환경부는 5곳의 물순환 선도도시를 공모하여 선정하였다. 또한 한국토지주택공사에서는 LID 분산형 빗물관리 기준을 수립하여 지구단위계획지침에 토지이용별 빗물관리 기준을 명시 하였으며, K-water는 에코델타시티와 송산그린시티 개발사업을 수행하면서 도시개발부터 건전한 물순환체계를 유지하기 위하여 저영향개발 기법을 적극 활용하기 위한 연구를 수행하고 있다. 본 연구에서는 수변도시 및 물순환 도시에 대하여 소개하고 수변도시, 물순환도시를 정의할 수 있는 여러 방향에 대한 고려사항을 제시하여 물순환 도시에서 검토되어야 할 사항을 확인하고자 하였다.