• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2011년도 춘계학술발표대회
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• pp.1068-1070
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• 2011

건물 부문의 에너지 절약방안으로 신재생에너지를 이용한 에너지 관리 시스템을 제안하고자 한다. 신재생에너지를 이용한 BEMS(Building and Enviromental Management System)를 설계하고, 이것을 구현하기 위한 Software Framework 를 설계한다.

• 경영과학
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• 제28권3호
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• pp.47-60
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• 2011

While the literature is replete with arguments that corporate strategy, structure, and culture independently matter in explaining the growth and survival of firms, little theoretical and empirical attention has been devoted to understanding how the three organizational factors develop over time in interaction. Through in-depth case study, we examine the POSCO's historical development with respect to the strategy-structure-culture interface. Furthermore, by looking at the POSCO's longitudinal financial data we gain insight into whether the aligned evolution of strategy, structure, and culture is associated with performance.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 추계학술대회 논문집
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• pp.79-80
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• 2013

MMC(Modular Multilevel Converter)는 여러 개의 Power Module을 직렬로 연결하여 정현파에 가까운 고전압의 파형을 얻을 수 있는 토폴로지로 대용량 전력변환 분야의 요구를 만족하면서 전력 품질을 향상시킬 수 있어 근래에 상당히 주목받고 있다. 당사에서는 5Mvar급 STATCOM(STATic synchronous COMpensator)을 MMC 형태로 제작하였다. 제작된 5Mvar급 STATCOM은 한 상당 12대의 Power Module로 구성하여 25-Level로 제작되었다. 제어시스템은 DSP(Digital Signal Processor)를 이용하였으며, 하나의 Main Controller와 다수의 Cell Controller, FPGA 보드 등으로 구성되어 있다. Controller 간의 상호 정보를 교환하기 위해 CAN 통신을 이용하였고, Power Module의 스위칭을 위한 보드는 각각에 연결되어 있으며, Cell Controller보드와는 절연을 위해 광신호로 연결하였다. 본 논문에서는 MMC 시스템의 제어기간 CAN 통신인터페이스와 Power Module의 PWM 동기화에 대해 설명을 하였다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 추계학술대회
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• pp.151-152
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• 2011

본 논문에서는 스마트 그리드에 적용되는 2MVA 배터리 에너지 저장 시스템(BESS, Battery Energy Storage System)의 제어 알고리즘을 제안하고 검증하였다. BESS는 전력변환을 위한 PCS(Power Conditioning System), 배터리 제어 및 상태확인을 위한 BCS(Battery Conditioning System)와 상위 시스템으로부터 지령을 받아 PCS와 BCS를 제어하는 PMS(Power Management System)로 구성되어 있다. BESS는 풍력안정화를 위해 EMS(Energy Management System)의 지령을 받아 운전모드를 선택하고, 운전모드에 따라서 계통측 전력을 제어하거나 배터리측 전류를 제어하고, 배터리의 완전충전을 위해 전압제어를 한다.

• Journal of Welding and Joining
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• 제25권2호
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• pp.55-61
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• 2007

Flash butt weldability of 590MPa dual phase steel is carried out under micro metallographical examination and macro mechanical property tests. The objective of present study is to investigate the cause that brings on bond line fracture, and is to improve mechanical properties of the flash butt welded joint. The joint of flash butt welding has a superior tensile property, but has bad formability due to oxide formed at bond interface. The HAZ softening in the weld joint does not show. It was found that mechanical properties were increased with optimizing welding parameters and making application of oil dripping and post-weld heat treatment.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.107-108
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• 2012

This paper presents design and implementation of the LDC(1.8 kW DC-DC Converter for Electric Vehicles). For Implementation of the LDC, the adapted topology is ZVS(Zero Voltage Switching) PSFB(Phase Shift Full Bridge) with Digital Control is adopted. Also, for the purpose of stable operation of the LDC in vehicle with variable electrical load condition, Continuous Voltage and Current Limit Control scheme based on PI controller are developed. According to real-car test mode, the prototype of proposed the LDC is verified with performance and stability. Thus, optimizing design and implement of the LDC are discussed, and experimental results are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 추계학술대회 논문집
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• pp.201-202
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• 2012

This paper presents design and implementation of the PCU(150 kVA 3-Phase PWM Inverter for Electric Vehicles). For Implementation of the PCU, it is consist with Case, Connectors, IGBT module for PWM switching, DC-capacitor for dc-source, resolver for sensing of speed & position, and PCB board for control & gate-driver. Also, for the purpose of stable operation of the PCU in vehicle with variable torque condition in motor, current control scheme based on torque-map are developed. According to real-car test mode, the prototype of proposed the PCU is verified with performance and stability. Thus, design and implement of the PCU are discussed, and experimental results are presented in this paper.

• Corrosion Science and Technology
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• 제10권1호
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• pp.30-36
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• 2011

The effect of dynamic flow or forced convection were investigated and compared on the formation of inhibition layer, galvanizing and galvannealing reactions through the hot-dip galvanizing simulator with the oscillation of specimen in zinc bath, continuous galvanizing pilot plant with zinc pumping system through the snout and continuous galvanizing operation with Dynamic $Galvanizing^{TR}$ system. The interfacial Al pick-up was not consistent between the results of simulator, pilot plant and line operation, but the morphology of inhibition layer became compact and refined by the forced convection. The growth of Fe-Zn intermetallics at the interface was inhibited by the forced convection, whereas the galvannealing rate would be a little promoted.

• 지식경영연구
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• 제9권1호
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• pp.147-161
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• 2008

In the previous KM (Knowledge Management) studies, it has been repeatedly pointed that CoP (Community of Practice) should be used as a platform for boosting up corporate innovative activities. Despite this, it is very rare to find relevant literature in which real-world cases are introduced showing critical success factors, implemented strategies, and objective analysis of results. In this sense, main objective of this paper is very timely- to introduce a real-world CoP case in which POSCO, world-leading steel company, sorted out creative CoP strategies to nurture knowledge-sharing activities to solve various kinds of problems at hand, and maintain appropriate level of knowledge circulation throughout all the working units of company. In a nutshell, POSCO has been successful in any measure in utilizing the creative CoP activities as strategic means to change the paradigm of innovation and extract fruitful outcomes from integrating three important individual activities such as work, learning, and innovation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2010년도 하계학술대회 논문집
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• pp.166-167
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• 2010

최근 전기/전자 제품 개발에서 대용량, 소형화가 이루어지면서 제품 설계에 열유동 및 구조적 문제가 중요한 요소로 등장하였다. 열유동은 발열체와 공기의 흐름에 관련이 있기 때문에 시스템의 구조를 어떻게 설계 하느냐가 방열의 중요한 요소이다. 본 논문에서는 Ansys사(社)의 소프트웨어를 이용하여 연료전지용 PCS에 대한 열유동, 구조 및 강도 해석을 수행하였다. 3D설계는 CAD(Computer Aided Design) 소프트웨어인 Pro Engineer를 이용하였다. 설계된 3D 도면을 Ansys Multiphysics로 불러들여 구조 및 강도해석을 하였고 CFD(Computational Fluid Dynamics) 소프트웨어인 Icepak으로 열유동해석을 수행하였다.