• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.245-248
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• 2001

Recently, with the advancement of internet network the system has been needed to be controllable and observable through internet at industrial workplace. In this study, we developed the digital timer which has a communication function to control and observe many kinds of devices by combining relay and timer used for each type of control panel to realize control solution based on internet to be easily applicable at workplace with low cost and adding 485 serial communication module to have parallel expansibility and safety. And, this system was experimented and designed for easy system management and status check from remote station through internet. appling the developed digital timer to parallel sequence control of motor. As the result of experiment, the circuit configuration would be more simplified than the existing, and it is expected that multi-connection control and monitoring can be simply implemented with low cost equipment at industrial workplace.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.157-160
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• 2001

Recently, with the advancement of internet network the system has been needed to be controllable and observable through internet at industrial workplace. In this study, we developed the digital timer which has a communication function to control and observe many kinds of devices by combining relay and timer used for each type of control panel to realize control solution based on internet to be easily applicable at workplace with low cost and adding 485 serial communication module to have parallel expansibility and safety. And, this system was experimented and designed for easy system management and status check from remote station through internet, appling the developed digital timer to parallel sequence control of motor. As the result of experiment, the circuit configuration would be more simplified than the existing, and it is expected that multi-connection control and monitoring can be simply implemented with low cost equipment at industrial workplace.

• 대한안전경영과학회지
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• 제12권3호
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• pp.257-262
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• 2010

The study investigates the various Acceptance Control Charts (ACCs) based on the factors that include process independence, data weighting scheme, subgrouping, and use of control charts. USL - LSL > $6{\sigma}$ that used in the good condition processes in the ACCs are designed by considering user's perspective, producer's perspective and both perspectives. ACCs developed from the research is efficiently applied by using the simple control limit unified with APL (Acceptable Process Level), RLP (Rejectable Process Level), Type I Error $\alpha$, and Type II Error $\beta$. Sampling interval of subgroup examines i.i.d. (Identically and Independent Distributed) or auto-correlated processes. Three types of weight schemes according to the reliability of data include Shewhart, Moving Average(MA) and Exponentially Weighted Moving Average (EWMA) which are considered when designing ACCs. Two types of control charts by the purpose of improvement are also presented. Overall, $\alpha$, $\beta$ and APL for nonconforming proportion and RPL of claim proportion can be designed by practioners who emphasize productivity and claim defense cost.

• 대한안전경영과학회지
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• 제10권2호
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• pp.133-141
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• 2008

The need for total enterprise management that covers from accepting orders, design, cost, procurement, manufacture, and delivery has been recently raised in order for efficient project management of small and medium size plant construction enterprises. This trend is reflected in the introduction of EPM(Enterprise Project Management) solutions by some shipbuilding enterprises and large construction corporations. In step with the trend, small and medium size plant construction enterprises are enabled to provide knowledge base in terms of reducing cost and production period and managing portfolio for accepting orders and attaining contract by inducing customized EPM This study presents a design of customized EPM based on a case study of a company. It exhibits a collaborative/collaboration resource-supply model which can be universally applied to small and medium size job-order production enterprises. The research discusses that under the assumption that information is shared internally between departments on planning, supply, manufacture, and quality control in order to create collaborative environment and close participation is created externally between suppliers and orderers, productivity can be improved in cost reduction through planning efficient collaborative supply model.

• 한국기계기술학회지
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• 제20권6호
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• pp.947-956
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• 2018

This research has been conducted to design upright parts of hand-made vehicles with the purpose of reducing material and machining cost while ensuring structural safety. Aluminum knuckles were modelled with three parts in order to enhance design flexibility as well as to reduce CNC machining cost. A vehicle model was constructed in CAD program and simulated in ADAMS View in order to estimate joint forces developing during 20 degree step steering condition at 60km/h. The joint forces obtained in the vehicle dynamics simulation were used for the structural analysis in ANSYS and dimensions of knuckle parts were adjusted until the lowest safety factor reached 2.0. The weight of knuckle decreased by 50% compared to the previous version that was designed without the structural analysis. The overall manufacturing cost decreased by 33% due to the reduction in the material as well as the CNC machining effort.

• 대한토목학회논문집
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• 제34권6호
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• pp.1919-1924
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• 2014

최근 기후변화로 인해 극한강우사상의 빈도 및 강도가 증가함에 따라 과거 기준에 의해 설계 시공되어 현재 운영 중인 댐의 수문학적 안전성에 의문이 제기되고 있다. 이에 따라 댐을 증고하거나 여수로를 확장/신설하는 방안이 추진되고 있는데, 이러한 대안을 선정할 때 월류 가능성에 매몰된 나머지 하류 홍수피해를 간과하는 경향이 있다. 이에 본 연구는 회복탄력성의 개념을 도입해 종합적인 홍수조절기능의 관점에서 댐의 안전성 강화 대안을 평가할 수 있는 프레임워크를 제시하였다. 제시된 프레임워크를 활용해 기 수행된 사례에 적용한 결과 각 대안에 따른 홍수유출특성이 선정과정에서 중요한 요소로 평가되어야 함을 확인할 수 있었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.117-129
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• 2009

This paper studied the safety management network system of infrastructure which constructed smart sensors, closed-circuit television(CCTV) and monitoring system. This safety management of infrastructure applied to bridge, cut slop and tunnel, embankment etc. The system applied to technologies of standardization guidelines, data acquirement technologies, data analysis and judgment technologies, system integration setup technology, and IT technologies. It was constructed safety management network system of various infrastructure to improve efficient management and operation for many infrastructure. Integrated safety management network system of infrastructure consisted of the real-time structural health monitoring system of each infrastructure, integrated control center, measured data transmission using i of tet web-based, collecting data using sf ver, early alarm system which the dangerous event of infrastructure occurred. Integrated control center consisted of conference room, control room to manage and analysis the data, server room to present the measured data and to collect the raw data. Early alarm system proposed realization of warning and response within 5 minute or less through development of sensor-based progress report and propagation automation system using the media such as MMS, VMS, EMS, FMS, SMS and web services of report and propagation. Based on this, the most effective u-Infrastructure Safety Management System is expected to be stably established at a less cost, thus making people's life more comfortable. Information obtained from such systems could be useful for maintenance or structural safety evaluation of existing structures, rapid evaluation of conditions of damaged structures after an earthquake, estimation of residual life of structures, repair and retrofitting of structures, maintenance, management or rehabilitation of historical structures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.15-19
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• 2002

To provide a specified power quality under electric market system is becoming an important issue for customers and utility company. However, there is no realistic infra-structure to design a power system for the specified power quality. Present electric market is operating under the economic point of view. The low price could be attractive. but the effect of low price and low power quality for the long time should be considered for the system safety. This paper presents a model which conceptualize the dynamic power quality control mechanism to minimize total cost of a society which is affected electric power quality. This model aims to produce a basic infra-structure to balance cost and quality under the electric market system.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.586-590
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• 2011

This paper presents the case study of the CE by collaborative system and proposes a model of the CM group for the cable supported bridge. The cable supported bridges have a large project scale and need a high level of construction method. Therefore an advanced construction management system is required for successful completion of project. The construction management (CM) group which control design management, construction plan, subcontract, technical support and R&D is organized for the cable supported bridge project. The CM group established a collaborative system with construction site and drew an effective management of cost, process, quality, safety for each project. Furthermore, the CM group established the procedure of construction management based on the construction engineering (CE) items and performed the project management on the construction phase. Efficiency of cost reduction and site control is maximized by using a collaborative system.

• 한국항해항만학회지
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• 제41권5호
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• pp.287-296
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• 2017

The Formal Safety Assessment (FSA) is a structured and systematic methodology developed by the IMO, aimed at assessing the risk of vessels and recommending the method to control intolerable risks, thereby enhancing maritime safety, including protection of life, health, the marine environment and property, by using risk analysis and cost-benefit assessment. While the FSA has mostly been applied to merchant vessels, it has rarely been applied to a DP vessel, which is one of the special purpose vessels in the offshore industry. Furthermore, most of the FSA has been conducted so far by using the Fault Tree Analysis tool, even though there are many other risk analysis tools. This study carried out the FSA for safe operation of DP vessels by using the Bayesian network, under which conditional probability was examined. This study determined the frequency and severity of DP LOP incidents reported to the IMCA from 2001 to 2010, and obtained the Risk Index by applying the Bayesian network. Then, the Risk Control Options (RCOs) were identified through an expert brainstorming and DP vessel simulations. This study recommends duplication of PRS, regardless of the DP class and PRS type and DP system specific training. Finally, this study verified that the Bayesian network and DP simulator can also serve as an effective tool for FSA implementation.