• 기술사
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• 제43권6호
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• pp.27-30
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• 2010

Gyeongbu high-speed railway project which comprises the construction of the new line with 417.5km between Seoul and Busan is one of the biggest national projects with approx. 20-trillion-won project cost. The construction was started in June 1992 and afterward phase I (between Seoul and Daegu) was opened in April 2004 and phase II (between Daegu and Busan, 169.5km) is scheduled for opening in the end of October 2010. It is assured that the opening of the entire sections of Gyeongbu high-speed railway will significantly increase productivity and efficiency by improving the land utilization with the promotion of personal and material exchanges induced by the reduction of travel time between regions. Especially, Gyeongbu high-speed railway will be the opportunity to boost speed-up of Korea railway.

• 한국산학기술학회논문지
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• 제11권10호
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• pp.3654-3657
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• 2010

본 연구에서는 LCD 디스플레이 프레임의 제품 원가를 절감하기 위해 조립공정의 최적화에 대해 연구하였다. 첫째로 OTRS를 이용하여 조립공정의 효율성을 분석하였고, 둘째로 낮은 가격의 원자재 코일을 대상으로 정해진 신뢰성 기준에 합격할 수 있는 프레임을 생산할 수 있는지 평가하였다. 연구 결과, 프레임 조립공정은 자동화가 상당 수준 진척되었기 때문에 높은 생산성이 유지되고 있다는 것을 알 수 있었고, 동시에 정해진 기준에 합격할 수 있는 프레임을 확보할 수 있는 가능성이 제시되었다.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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• pp.734-737
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• 2004

When the margin level is set relatively low, margin violation probability increases and the default probability of the futures market rises. On the other hand, if the margin level is set high, the margin violation probability decreases, but the futures market becomes less attractive to hedgers as the investor's opportunity cost increases. In this paper, we investigate whether the movement of KOSPI200(Korea Composite Stock Price Index 200) futures daily prices can be modeled with the extreme value theory. Base on this investigation, we examine the validity of the margin level set by the extreme value theory. Computational results are presented to compare the extreme value distribution and the empirical distribution of margin violation in KOSPI200. Some observations and implications drawn from the computational experiment are also discussed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.830_831
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• 2009

Wind power system attracts most interest because of high-energy efficiency with environment-friendly. Small scale wind power applications requires a cost effective and mechanically simple generator in order to be a reliable energy source. The use of direct driven generators, instead of geared machines, reduces the number of drive components, which offers the opportunity to reduce costs and increases system reliability and efficiency. This paper presents the development of a coreless axial-flux permanent magnet(AFPM) generator for a urban wind power system. It is analyzed by electromagnetic simulation program Maxwell 3D

• 한국소음진동공학회논문집
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• 제19권7호
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• pp.673-678
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• 2009

The efficiency of active sonar that is used underwater observation equipment is important for obtain the information of topography and trace for the objects. Sound wave transmitted from sonar are distorted by acoustic window which is to protect sonar. Making various sonar dome is impossible for experiment, because consumed unnecessary time and expense. So, the purpose of this study is to simulate and analyze the acoustic window propagated sound wave from sonar for designing model reduced insertion loss. Simulation is performed by transient analysis and fluid-structure interaction analysis. As a result, this study will give a opportunity for efficient design of sonar dome without high cost and time consumption.

• 경영과학
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• 제12권2호
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• pp.77-87
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• 1995

In this paper we develop an efficient heuristic algorithm for the problem of scheduling n sequence-dependent jobs on a basic processor to minimize makespan. Efficient solution methods are already known for the sequence- independent case. But for the sequence-dependent case, this problem belongs to a set of strong NP-complete problems. We present a heuristic which is similar to shortest setup time heuristic but opportunity cost of setup time rather than shortest setup time is used for choosing next job. This heuristic algorithm has same computational complexity and worst case ratio as the shortest setup time heuristic. We used Wilcoxon signed rank test to show that our heuristic is superior to nearest setup time heuristic in term of average behavior.

• 한국콘텐츠학회논문지
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• 제2권1호
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• pp.46-51
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• 2002

인터넷의 발전과 더불어 많은 기업이 생산성을 향상하고 경쟁적 우의를 제고하는 한편 전세계적으로 고객의 저변확대를 하고 있다. 전자상거래의 도입 .확산과 관련하여 정부가 개입해야 할 필요성은 전자상거래가 미치는 파급효과에서 찾을 수 있다. 전자상거래가 경제적으로 미치는 가장 큰 파급효과는 일반적으로 사회 전반적인 거래비용의 절감으로 보고 있다. 이러한 시점에서, 본 연구는 기업간 전자상거래의 활성화에 영향을 주는 주요성공요인 분석을 통해 정부의 주도적인 역할이 필요한 세 가지 측면의 주요성공요인을 도출하고, 각 측면에서의 정부의 역할 및 정책 방안을 제안하고 있다.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.22.1-22.1
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• 2008

Media company is not a business which sells news and information but a company sells audience's attention. Advertisers estimate audience's quantity and quality which pay attention to media and pay the cost. Thus drawing audience's attention is a natural and instinctive behavior for survival of media company. News doesn't deliver the fact just as it. That's impossible. News is a commodity made by processing and selection of the media company and journalist. On the process, judge of values is involved and limitation of time and place of media is considered. If scientists understand media's character truly, their misunderstanding about media company and journalist may be cleared up. In this society, media is not a being to ignore, particularly for big science like space science which spends huge public capital. Nowadays, space science meets the time to take the leap in Korea. However that can be crisis cause of uncertainty of science activity. When the crisis which no one desires happens, preparation needs for new opportunity. We can take the crisis as a chance. Understanding about media and public will be the first step for this preparation.

• 시스템엔지니어링학술지
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• 제10권2호
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• pp.89-95
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• 2014

In recent years, the United States have been several major failures of launch. As a result of these failures, activity of mission assurance valued. Mission assurance is defined as the application of systems engineering process towards the goal of achieving mission success. Therefore, mission assurance perform independent technical assessments throughout the concept and requirements definition, design, development, production, test, deployment, and operations phases. Space system program was emphasized the importance of the system engineering for that required huge cost and long term development. For this reason, independent review and verification of mission assurance is essential. Mission assurance gives us confidence to proceed with launch and best opportunity for mission success. In this study, framework of mission assurance is proposed by foreign case analysis.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.83-89
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• 2001

This paper provides a short description of the COMPASS-model which is a concept for the simulation of multiway systems. The focus of the COMPASS-model is to offer an opportunity to investigate the effects of redistribution strategies on logistic and monetary values in a system of returnable transport items (RTI). The modeling concept consists of five modules: topology, system load, distribution, redistribution, cost. It includes the integration of highly sophisticated evolutionary algorithms for the optimal solving of complex capacitated vehicle routing problems (CVRP) which are typical for RTI-systems. The results of first experiments with a COMPASS-based prototype are repeated. They reveal some basic regularities in RTI-systems.