• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.7
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• pp.767-774
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• 2012

A fluidic device (FD) has been adopted in the safety injection tanks (SITs) of APR1400. A flow control mechanism of the FD was used to vary the flow regime in the vortex chamber corresponding to the SITs water level. The flow regime in the vortex chamber has a different pressure loss from low to high in accordance with the SITs water level. Nitrogen at the top of the SIT could be released owing to inertia of discharge flow when changing from a high flow rate to a low flow rate. This phenomenon is important to design improvement perspective because it can affect the performance of the FD. This paper shows a result of a preliminary numerical study to obtain the transient data related to air release in the flow turn-down period using a two-fluid free-surface model provided from ANSYS CFX 13.0. In conclusion, there is no significant effect on the performance of the FD, though a small quantity of air is released during the flow turn-down period.

• Journal of Digital Convergence
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• v.13 no.8
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• pp.235-243
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• 2015

Recently, due to the spread of the Korean Wave, as worldwide interest in Korean culture and the appearance of Korean celebrities increases, overseas expansion of Korean beauty companies have been activated. Despite the global economic downturn, Beauty Industry is continuing to grow, Korea's growth rate is remarkable level. Despite this growth in order to maintain a steady growth since the beauty industry is small and polarization based on the Beauty-IT Convergence Technology creates new markets, that require development of Beauty-IT Convergence Industry. For the status and prospects of the Beauty Industry, some research has been carried out, not all the studies carried out so far for Beauty-IT Convergence Industry. Therefore, this study is significant that Beauty-IT Convergence Industry's first research. The global Beauty-IT Convergence Industry is at the beginning yet, tThe government selected research topics of Top-Down approach to Beauty-IT Convergence technology, granted extra points, supported by establishing long-term Technology Roadmap as other industries, such as by establishing a global market strategy for the systematic occupation and promising technology development planWe will get focused training.

• Journal of Korea Game Society
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• v.11 no.1
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• pp.159-168
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• 2011

Online game industry has achieved remarkable development not only in Korea, but also in the world with support from huge progress in information technology. By the way, there was calm period that top tier MMORPGs had held their ranks in oligopoly situation before Aion's appearance. At that time, NHNgames succeeded to penetrate into the market and settle down as a major player. In this context, this study will identify the factors of successful market entry strategy and draw helpful ideas by analyzing case of NHNgames which succeeded to enter the market of MMORPG through the basic strategic framework of Kalyanaram and Gurumurthy. This discussion will provide several implications for the solution of online game market penetration problem which might be never ended and for the way of industry's development.

• Korean System Dynamics Review
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• v.14 no.3
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• pp.51-74
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• 2013

Recently, Community Rebuilding Projects (hereinafter CRPs) in Korea have been driven and motivated by community inhabitants by themselves, and highlighted as an alternative approach to overcome the limitation revealed normally in top-down projects of community vitalization by the Government. The CRPs encourage community-lead development because it happens to integrate multiple stakeholders and to help inhabitants to participate in the process of the CRPs by accumulating and enlarging social capital and network among inhabitants, and the social gain consequently raises the efficiency of public investment in revitalizing communities. In this study, the series of Causal Loop Diagrams (CLDs) is to be elaborated and the System-Thinking (ST) approach is to be presented to understand the dynamic characteristics residing in the above development process of rebuilding communities. The ST approach refers to the CLDs analyzing 19 remarkable Korean CRP cases, and leads to a conclusion including some of policy instruments to support the bottom-up CRPs in Korea. This study contributes a theoretical framework to understand the dynamic relation between social capital and community revitalization as well as empirical suggestions to respond to the issues of the CRPs in Korean local governments.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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• pp.559-562
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• 2004

The methodologies to develop land use plans are divided into two different ways, top-down and bottom-up planning. The bottom-up method is more efficient and effective to detailed land use planning. However, it requires considerable amount of information about the present status of land use. Cadastral information system is one of the best information provider for the planning. Building Register Database shows the type, area, use and location of a building. Both cadastral and Building Register systems apparently contain useful information needed to the physical planning. The study focuses on developing a prototype to provide real time information for detailed physical planning by a federated database system using the two databases.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.189-192
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• 2012

Underground structure construction in the downtown is very difficult despite the development of construction technology. We have been a lot of research in order to solve the problem, it was a remarkable achievement. But there are still many difficulties. This study is to analyze the construction technology to demolish the existing underground structures and to build new building applied topdown method at the same time. This technology was effective to suppress interference between the exsisting structure and new building. Therefore, this technology is expected to be able to be used in similar cases in the future.

• Journal of the Korea Institute of Military Science and Technology
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• v.16 no.3
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• pp.348-357
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• 2013

This work describes an approach that contributes to derive from mission to critical functions of the attack helicopter under future battle space environment. An existing mission of the attack helicopter is limited to the only shooter oriented functions. In the future environment, mission and its functions of the helicopter might be much expanded. The functions should be derived by the top down approach based on systems engineering approach. In this point of view, this work describes network based future battle environment. From this environment, the missions of the attack helicopter are identified and optimized functions are derived through sequential procedures like from missions to tasks, tasks to activities, and activities to functions. The selected activities are obtained from the tasks using QFD. The weighting scores of the QFD are calculated by the AHP computational procedure. Finally the critical functions are presented through the similar procedure.

• Journal of the Korean Institute of Navigation
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• v.19 no.3
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• pp.29-34
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• 1995

IEC and CISPR have continuously endeavored the measurement method of Immunity Test as international unification, but not established yet. The main reason is that the measurement method and the normalization of threshold to obtain the complicated parameters for Immunity Test are difficult. Thus, the Immunity Test Setups are used differently according to the measured electromagnetic environments. This study developed an Immunity Test System and Algorithm for measurement software suitable for IEC801-3 Regulatons using ready-made amplifier, signal generator, and developes interconnecting interface board interacting with other appratus i.e., RF Switch, Power Meter, Field Sensor and Pre-amp. We are to develope an automated software using Top/Down and OOP(Object Oriented Programming) method.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.09a
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• pp.300-324
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• 1995

This research investigates the automatic identification of typical embedded structures in the Integer Programming(IP) models and automatic transformation of the problem to an adequate Lagrangian problem which can provide tight bounds within the acceptable run time. For this purpose, the structural distinctiveness of variables, constants, blocks of terms, and constraint chunks is identified to describe the structure of the IP model. To assist the identification of the structural distinctiveness, the representation by the knowledge based IP model formulator UNIK-IP is adopted. For the reasoning for the structural identification, the bottom-up, top-down, and case-based approaches are proposed. A prototype system UNIK-RELAX is developed to implement the approaches proposed in this research.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.3
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• pp.89-98
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• 2014

Platform-based product family design is recognized as an effective method to satisfy the mass customization which is a current market trend. In order to design platform-based product family successfully, it is the key work to define a good product platform, which is to identify the common modules that will be shared among the product family. In this paper the clustering analysis using dendrogram is proposed to capture the common modules of the platform. The clustering variables regarding both marketing and engineering sides are derived from the view point of top-down product development. A case study of a cordless drill/drive product family is presented to illustrate the feasibility and validity of the overall procedure developed in this research.