• Nuclear Engineering and Technology
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• v.41 no.5
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• pp.561-574
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• 2009

First ex-vessel core catcher has been applied to the practical design of NPPs with VVER-1000 reactors built in China (Tyanvan) and India (Kudankulam) for severe accident management (SAM) and mitigation of SA consequences. The paper presents the concept and basic design of this crucible-type core catcher as well as an evaluation of its efficiency. The important role of oxidic sacrificial material is discussed. Insight into the behaviour of the molten pool, which forms in the catcher after core relocation from the reactor vessel, is provided. It is shown that heat loads on the water-cooled vessel walls are kept within acceptable limits and that the necessary margins for departure from nucleate boiling (DNB) and of vessel failure caused by thermo-mechanical stress are satisfactorily provided for.

• Journal of Navigation and Port Research
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• v.40 no.5
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• pp.265-270
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• 2016

Extreme tropospheric anomalies such as typhoons or regional torrential rain can degrade positioning accuracy of the GPS signal. It becomes one of the main error terms affecting high-precision positioning solutions in network RTK. This paper proposed a detection algorithm to be used during atmospheric anomalies in order to detect the tropospheric irregularities that can degrade the quality of correction data due to network errors caused by inhomogeneous atmospheric conditions between multi-reference stations. It uses an atmospheric grid that consists of four meteorological stations and estimates the troposphere zenith total delay difference at a low performance point in an atmospheric grid. AWS (automatic weather station) meteorological data can be applied to the proposed tropospheric anomaly detection algorithm when there are different atmospheric conditions between the stations. The concept of probability density distribution of the delta troposphere slant delay was proposed for the threshold determination.

• Journal of the Korean housing association
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• v.13 no.5
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• pp.1-8
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• 2002

Contemporary architecture shows complex aspects of various design in form and material. Such trends even change classical materiality and this concept is believed to be the background of current ideas - digital, information, imagination with paradigm. This study inquires the general concept of dematerial. In the process searching for the forming basic background this study understands the characteristic. With characteristics drawn in chapter three, this study show the present status of the architectural expressions in the contemporary house in Korea under its dematerialized situation. And like this, we know fur study about the relation between dematerialization and current architecture, still more Korean present condition.

• Journal of the Korean Electrochemical Society
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• v.7 no.3
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• pp.155-162
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• 2004

This article covers the fundamentals of percolation phenomenon giving emphasis to the percolation concept involved in disordered electrochemical systems. After a brief discourse on the basic concepts of percolation theory, the geometrical properties and fractality of percolation clusters were presented. Then, anomalous behaviours of diffusion in percolation clusters were explained in terms of the fractal structures of the infinite percolation clusters. Finally, the conductivity-related properties of composite ionic materials were shortly discussed on the basis of percolation theory from practical points of view.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.25 no.4
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• pp.141-153
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• 2017

Various aviation safety performance and safety oversight programmes including CRM, SMS and USOAP are operated in various sizes, depending on the capacity of each State. Despite such activities, greate and small, aviation incidents and accidents are continuously occurred. In relation to this point, this paper suggests a result of comprehensive literature review for the purpose of building an aviation safety performance theory. This paper will define the concept of aviation safety and following created common perception on aviation safety will, as basic materials, contribute to pursue consistence and systematic aviation safety activities.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.18 no.1
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• pp.45-50
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• 2010

Air Traffic Management aims to fulfill the requirement of the aviation demander by constructing the most effective and safety aviation systems for providing safety and cost-effective service. All concerned parties of aviation present the needs of improving Air Traffic Management system for solving the issue of the current system and the air traffic capacity in the 21st century, and introduce the significant improvements from the conventional technology and method for the past 40 years. Accordingly, ICAO promotes the development of innovative procedures and technologies to solve the problems and meet the demands. It is the concept of Performance based Navigation(PBN) based on Communication, Navigation, and Surveillance/Air Traffic Management(CNS/ATM). This study defines differences between RNAV and RNP RNAV as methods of air navigation based on the CNS/ATM, and needs and requirements of PBN as an emerging global standard. It also outlines basic elements supporting and implementing the PBN concept.

• Korean Institute of Interior Design Journal
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• no.34
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• pp.86-95
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• 2002

In the 1950’s, after modernistic hospital is begun to build in our country, there were much changes in hospital construction plan such as function, scale, operation, technology for 40 years so far. Interest about 'Healing environment furtherance' which is one of basic function of hospital within these change is continued. Specially, concept about furtherance of healing environment limited in ward department in the early time is applied to hospital space magnificently whole coming at present. Entrance of hospital and change of Lobby may speak as the representative example. This interest about practically use of lobby is rising gradually. Lobby adds to existed concept of space to the importance revaluated. The first purpose of this study is to investigates main entrance and lobby of representative hospital in our country and to search change and present condition. The second purpose is hereupon to present necessary objective standard with direction of lobby plan in general hospital forward though this.

• Industrial Engineering and Management Systems
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• v.12 no.1
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• pp.16-22
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• 2013

This paper proposes a new concept of comonotonicity of uncertain vector based on the uncertainty theory. In order to understand the comonotonicity of uncertain vector, some equivalent definitions are presented. Following the proposed concept, some basic properties of comonotonic uncertain vector are investigated. In addition, the operational law is given for calculating the uncertainty distributions of monotone functions of comonotonic uncertain variables. With the help of operational law, the comonotonic uncertain vector is applied to the premium pricing problems. At last, some numerical examples are given to illustrate the application.

• Journal of computational fluids engineering
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• v.8 no.4
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• pp.26-33
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• 2003

Smart UAV Development Program, one of the 21c Frontier R&D Program sponsored by MOST(Ministry of Science and Technology), was launched in 2002 As an air vehicle for the Smart UAV, CRW(Canard Rotor/wing) concept was one of the candidates compared in trade-off study. The CRW concept has not only been proven completely but its aerodynamic characteristics not known in detail yet. Two calculation methods were adopted in this study to obtain aerodynamic data for the CRW First method was the superpose DATCOM method which is capable of three lifting sufaces, and second one is the full Navier-Stokes computation around CRW configuration using overset grid method. Basic aerodynamic characteristics of the CRW configuration was analyzed and the minimum drag level with lift to drag ratio is presented. The peculiar flow characteristics around rotor/wing and hub were also examined and considered in the configuration design.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2006.11a
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• pp.193-196
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• 2006

The meaning of the color which has from modern interior space has played important role, i.e. color itself Is the concept creation tool as well as the unique expression sphere in field of interior space far away from fixed idea relevant to the existing color which was only simple decoration or secondary element in space. Thus, this current work expresses that the color is related with decoration effect as well as basic designed-conceptual work process including the space is formed. Furthermore, through the side-composition with color, It activates the various space aspect perceptually, which created the colorful environment in using lightning, reflection of glass and penetrated nature etc. The keyword on color concept is as like various aspects, third dimension, non-materiality and symbolical meaning. In addition, it provides the color space equipped with functionality and artistry capable to arouse the diverse sensual capacity to space users on default of color image language.