• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.159-162
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• 2002

A software, called touch-one, is developed about the determination of short-circuit values and protective co-ordination in power system. The used solution algorithm reviewed intensively, and the protective co-ordination determination technique presented by using the circuit-breaker's current-limitation characteristic. The protective coordination concerns the behaviour of two devices placed in series in an electrical network, with a short-circuit downstream circuit-breaker. It has two basic principles: First, discrimination which is an increasing requirement of low voltage electrical distribution systems. Second, which is less well known: cascading, which consists of installing a device, whose breaking capacity is less than the three-phase short-circuit current at its terminals and helped by main circuit-breaker. With this software, we can construct a electric-power system which is reliable and economic according to user's purpose.

• KDI Journal of Economic Policy
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• 제37권3호
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• pp.1-30
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• 2015

Based on a quantitative, heterogeneous agent general equilibrium model, we compute the optimal tax rates for labor and capital incomes for the Korean economy. According to our model, a more progressive income tax schedule along with a higher capital tax rate can increase average welfare by as much as 0.86% of permanent consumption. Approximately 64% of house-holds, those with low assets and low productivity, are better off when a more progressive optimal tax schedule is adopted. Despite the potentially significant welfare gains, our calculation should be interpreted with caution because our benchmark model does not take into account possible capital outflows or the increased administrative costs associated with high taxes.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2001년도 춘계 공동학술발표회 논문집
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• pp.66-70
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• 2001

Recently, mega-float offshore structure is studied as one of the effective utilization of the ocean space. And mega-structure are now being considered for various applications such as floating airports, offshore cities and so on. This mega-float structure is relatively flexible compared with real floating structures like large ships. when we estimate dynamic responses of these structures in waves, the elastic deformation is important, because vertical dimension is small compared with horizontal. The analysis of the dynamic response as it receives regular wave is studied. The finite element method is used in the analysis of structural section of this model. And the analysis is carried out using the boundary element method in the fluid division. In order to know the characteristics of the dynamic response of the mega-float structures, effects of wavelength, water depth, and wave direction on dynamic response of the floating structure are studied by use of numerical calculation.

• 수산해양교육연구
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• 제26권1호
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• pp.126-133
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• 2014

For boarding comfort and pleasant boarding sensitivity of passenger in passenger ship, there are a few methods such as motion sickness rate or MSI(Motion Sickness Incidence) to assess safety of passenger ship. To find out MSI or motion sickness rate of the training vessel Kaya of Pukyong National University, we use lots of various factors: sea condition, incident angle in main sail way, economic speed, calculation position of motion sickness, sea state, work place and reduce zone of ship. In this paper, we adopted Maxsurf Seakeeper program based on Strip Theory and carefully compared theoretical results with experimental results.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.582-582
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• 2012

Characteristics of a fusion-driven transmutation reactor was investigated. A compact reactor concept is desirable from an economic viewpoint. For the optimal design of a reactor, a radial build of reactor components has to be determined by considering the plasma physics and engineering constraints which inter-relate various reactor components. In a transmutation reactor, design of blanket and shield play a key role in determining the size of a reactor; the blanket should produce enough tritium for tritium self-sufficiency, the transmutation rate of waste has to be maximized, and the shield should provide sufficient protection for the superconducting toroidal field (TF) coil. To determine the radial build of the blanket and the shield, not only a radiation transport analysis but also a burnup calculation were coupled with the system analysis and it allowed the self-consistent determination of the design parameters of a transmutation reactor.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 추계학술발표회 논문집
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• pp.47-53
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• 2004

Water vapor is an important parameter in monitoring changes in the Earth's climate and it can be used to improve weather forecasting However, it haven't observed accurately by reasons of structural and economic problem of observation. GPS meteorology technique for precipitable water vapor measurement is currently actively being researched an advanced nation. Main issue of GPS meteorology is an accuracy of PWV measurement related weighted mean temperature and meteorological data. In this study, the korean weighted mean temperature had been recalculated by a linear regression method based on meteorological observations from 6 radiosonde stations for 2003 year. We examined the accuracy of PWV estimates from GPS observations and Radiosonde observations by new korean weighted mean temperature and others.

• International Journal of Aeronautical and Space Sciences
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• 제9권1호
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• pp.42-47
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• 2008

One of the main cases of the desertification impact is the negative contribution of human activities that worsen environment. There are historical facts of inability and excessive activities which destroyed the civilizations. The basic difference is only in the tempo and scales of civilization collapse. Human pressure was accumulated within the centuries and millennia due to the extremely active economic activities. But today it covers only the decades. Presently the process of desertification has a global scale. There are huge factors of Earth aridization as an increase of the quantity of C02 and atmospheric dust and bloom. This process related not only to the arid areas. Obviously a comprehensive approach of development of territories, particularly arid areas is very important. The use of the satellite information and technologies of remote sensing data processing can take a significant place for decision-makers for calculation and estimation of the environment impacts.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1997년도 하계학술대회 논문집 D
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• pp.1153-1155
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• 1997

Electric business all over the world is dramatically changed from vertically integrated monopoly to competition systems. Also, independent power producers(IPPs) will start their commercial operation from the year 2001 in Korea. In this regard, determination of the transaction cost between IPPs and electric utilities will be a hot issue, and electric utilities requires a new framework to support their decision-making. This paper presents the concept of the avoided cost which can be used for economic studies. This paper also describes a novel algorithm to evaluate the avoided cost of a IPP. The case studies are performed on the basis of the official generation expansion plan of Korea by using the Wien Automatic System Planning Package(WASP).

• 해양환경안전학회지
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• 제4권2호
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• pp.35-42
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• 1998

Marine casuality causes not only loss of lives and ships, but also severs damages to marine environment and related economic activities such as fishing industry, sea farming, and tourist industry. Basically, the great effort should be made to prevent the occurrence of maritime accidents by any means. However, once accident has occurred, the salvage works should be done rapidly and properly based on theoretical and technical informations, which could minimize the risk during salvage operation and the overall damage from the maritime accidents. Generally, to calculate accurate hydrostatics of a stranded ship, a large amount of input data is needed. But, an availability and a reliability of input data cannot be guaranteed in most situations, and the adequate time required for preparing all input data is not allowed to perform the timely operations of salvage. In this paper, the development process of simple computer program for salvage operation using limited input data is introduced and its application example is presented. This program was developed to provide technical support for planning salvage operations in the grounding accident.

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2003년도 종합학술대회 논문집
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• pp.197-203
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• 2003

The purpose of the study is to develop an integrated knowledge structuring system for the domain of engineering, in which ontology-based literature mining, knowledge acquisition, knowledge integration, and knowledge retrieval are combined using XML-based tag information and ontology management. The system supports combining different types of databases (papers and patents, technologies and innovations) and retrieving different types of knowledge simultaneously. The main objective of the system is to facilitate knowledge acquisition and knowledge retrieval from documents through an ontology-based dynamic similarity calculation and a visualization of automatically structured knowledge. Through experimentations we conducted using 100,000 words economic documents reported in the "Go！ Japan" project for analyzing Japanese industrial situation, and 100,000 words molecular biology Papers, we show the system is Practical enough for accelerating knowledge acquisition and knowledge discovery from the information sea.