• Korean Journal of Computational Design and Engineering
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• v.15 no.2
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• pp.94-105
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• 2010

Todays, there is fast transition about the new manufacturing IT methodologies from the conceptual phase into the practical application phase for the strengthening of enterprise competitiveness in manufacturing industry. One of those new methodologies is PLM (Product Life-cycle Management). PLM methodology consists of 3D CAD for the product design, PDM (Product Data Management) for the data management based on the collaboration platform and lastly DM (Digital Manufacturing). DM has evoluted from the stand-alone computer simulation of early 1980s, and now it covers the overall production development and production. Unfortunately, there exist serious critical problems about the actual application of DM for the real work. This is owing to the transition of the point of view from stand-alone type application (such as flow simulation or robot simulation) to that of business process about product development and production management. In this paper, we propose an application framework for the successful project with the digital manufacturing methodology with the concept of Information Strategy Planning, which enables the systematic diagnosis and the quantitative evaluation. Also, we introduce the actual practice of the proposing framework with the ISP project for 'Analysis & Simulation Technique of manufacturing process project' that is being conducted by Chungnam Techno Park.

• Strategy21
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• s.36
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• pp.180-214
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• 2015

The Republic of Korea navy challenged from the unexpected surprise attacks by the North Korea navy, albeit, the developments of up-to-date naval forces' technology, and the ceaseless efforts for war preparedness. My study divided into two categories. Qualitative methods used for literature review of international relations theory related to the war onset and for investigating events occurred on the Peninsula and its surrounding seas from 1968 to 2007. Quantitative method used such as the analyses of national power index of the two Koreas, the United States, and China, the uses of equation model to calculate power index of alliance, COPDAB(Conflict and Peace Data Bank) index analysis. Like Choi's study on East Asia maritime conflict, as a conclusion, considering both AT theory and maritime national power as a tool for predicting maritime conflict in the Peninsula proved significant. Based on the study, ROK navy need to prepare for the maritime conflict because the results showed North Korea would initiate maritime disputes sooner or later using fatal asymmetric forces and methods. As a policy suggestion, we are required to maintain a concrete ROK-US alliance ties and to construct naval forces due to the deterring functions of maritime national power.

• Journal of Power Electronics
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• v.15 no.4
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• pp.1026-1034
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• 2015

In this paper, a unified control strategy using the current space vector modulation (CSVM) technique is proposed and applied to a bidirectional three-phase DC/AC converter. The operation of the converter changes with the direction of the power flow. In the charging mode, it works as a buck type rectifier; and during the discharging mode, it operates as a boost type inverter, which makes it suitable as an interface between high voltage AC grids and low voltage energy storage devices. This topology has the following advantages: high conversion efficiency, high power factor at the grid side, tight control of the charging current and fast transition between the charging and discharging modes. The operating principle of the mode analysis, the gate signal generation, the general control strategy and the transition from a constant current (CC) to a constant voltage (CV) in the charging mode are discussed. The proposed control strategy has been validated by simulations and experimental results obtained with a 1kW laboratory prototype using supercapacitors as an energy storage device.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.3
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• pp.258-266
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• 2012

This paper describes a biped walking algorithm for a hydraulic humanoid robot on inclined floors. To realize stable and robust biped walking, the walking algorithm was divided into five control strategies. The first is a joint position control strategy. This strategy is for tracking desired joint position trajectories with a gain switching. The second is a multi-model based ZMP (Zero Moment Point) control strategy for dynamic balance. The third is a walking pattern flow control strategy for smooth transition from step to step. The fourth is an ankle compliance control, which increases the dynamic stability at the moment of floor contact. The last is an upright pose control strategy for robust walking on an inclined floor. All strategies are based on simple pendulum models and include practical sensory feedback in order to implement the strategies on a physical robot. Finally, the performance of the control strategies are evaluated and verified through dynamic simulations of a hydraulic humanoid on level and inclined floors.

• Journal of the Korean Operations Research and Management Science Society
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• v.6 no.2
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• pp.57-64
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• 1981

This paper develops a method of modifying the usual maximum likelihood estimators of the parameters of a two state Markov process when the trajectory of the process can only he observed at regular epochs. The method utilizes the limiting behaviors of the process and the properties of state transition counts. An efficient adaptive strategy to be used together with the modified estimator is also proposed. The properties of the new estimators and the adaptive strategy are investigated using Monte Carlo simulation.

• Proceedings of the KIPE Conference
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• 1998.07a
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• pp.10-13
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• 1998

In this paper, a control strategy of the three phase ZVT inverter for ac motor drives is proposed. The topology of ZVT inverter analyzed with a description of the control conditions dependent on the load current and MSVM(Modified Space Vector Modulation). The detailed simulation results indicate that zero-voltage operation during transition of the MSVM algorithm can be achieved.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.04a
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• pp.30-33
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• 2004

This paper suggested that the technical specification of tilting train EMU for speed up on existing lines. High speed strategy of existing lines are the modification of railway system which are made on cant, lengths of transition curves, the catenary system and train system. Tilting technology is more useful a strategy for speed increases on existing lines with low investment needed. We performed a feasibility study which is considered out real track conditions and designed propulsion and braking system of tilting EMU system.

• Journal of the Speleological Society of Korea
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• no.92
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• pp.41-47
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• 2009

This study discussed revitalization of commercial caves. Transition of approach method about cave development is required. Each of the caves need differentiation strategy. In addition, the recognizing of the value of caves is required.

• Korean journal of communication and information
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• v.21
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• pp.63-86
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• 2003

Digital TV is expected to usher in a new era of TV. Thanks to digital and network technologies, TV will no more be a dumb terminal as it is today. It will incorprate the computer and thus become an intelligent device which serves not only high quality broadcast programming, but a variety of information services much like the current networked-computer. However, the real world picture of digital TV is clearly different from such a rosy vision. Albeit too early to tell, the cases in Europe and the US attest that the digital transition suffers a setback in terms of technology, policy, business, marketing, and the users. As such, the digital transition is generally problematized in terms of policy, business model, marketing strategy, and so on. Comparatively speaking, the issues of technology, policy, business and marketing are not so complicated than that of digital TV users because of the cultural issues involved in the adoption of digital TV. In other words, the technological transition to digital TV is far easier than its cultural transition. The cultural transition demands policy makers and industries of different approaches to successfully facilitating the digital transition.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.2
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• pp.337-342
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• 2018

Spent fuel is moved from the reactor into the spent fuel pool when nuclear power plant permanently shutdown. The sole function of a permanently defueled facility is to store spent fuel in a quiescent state. The function of electric system and loads are reduced. It is necessary to establish an operating strategy of electric system in the permanent shutdown nuclear plant. This paper reviews required loads and design criteria considering transition to permanent shutdown. An operating strategy of onsite electric system is proposed considering decommissioning strategy and stage of defueled condition.