• 한국전산구조공학회논문집
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• 제16권3호
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• pp.291-299
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• 2003

본 연구에서는 연속체해석을 토대로, 병렬코아를 갖는 아웃리거구조물의 수평하중에 대한 응력과 변위를 구하기 위한 방법을 제안하였고, 아웃리거의 위치에 따른 구조물의 거동에 대해 연구하였다. 아웃리거와 코아가 만나는 위치에서 코아의 회전병위가 아웃리거의 회전변위와 일치한다는 적합조건으로부터 아웃리거의 구속모멘트, 코아의 휨모멘트, 기둥의 축방향력, 그리고 구조물의 수평변위 등을 유도하였다. 구조모델들을 이용하여 MIDAS-GEN 프로그램에 의한 결과와 비교하였고, 병렬코아를 갖는 아웃리거구조물에 대해 만족할만한 결과를 얻었다. 구조물 최상단의 수평변위는 코아의 위치보다는 아웃리거의 위치에 의해 크게 영향을 받는 것으로 조사되었다. 비록, 이 논문에서 제시된 공식들이 이상적인 아웃리거구조물에 대한 것이지만 병렬코아를 갖는 실제 아웃리거구조물의 응력과 변위의 근사치를 추정하고, 구조물의 거동을 예측하기 위한 수단으로 유용하게 사용될 수 있을 것이다.

• Journal of Power Electronics
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• 제19권2호
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• pp.344-352
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• 2019

To achieve high efficiency and reliability, multiphase interleaved converters with coupled inductors have been widely applied. In this paper, a coupled inductor design method for 2-phase interleaved boost converters is presented. A new area product equation is derived to select the proper core size. The wire size, number of turns and air gap length are also determined by using the proposed coupled inductor design method. Finally, the validity of the proposed coupled inductor design method is confirmed by simulation and experimental results obtained from a design example.

• JSTS:Journal of Semiconductor Technology and Science
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• 제17권1호
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• pp.42-47
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• 2017

This paper proposes a new series-coupled voltage-controlled oscillator (VCO). The proposed VCO consists of four current-reuse Armstrong VCOs (CRA-VCOs) coupled by four transformers. The series-coupling, current-reuse, and Armstrong topologies improve the phase noise performance by increasing the negative-Gm of the VCO core with half the current consumption of a conventional differential VCO. The proposed VCO consumes 6.54 mW at 9.78 GHz from a 1-V supply voltage. The measured phase noise is -115.1 dBc/Hz at an offset frequency of 1 MHz, and the FoM is -186.5 dBc/Hz. The frequency tuning range is from 9.38-10.52 GHz. The core area is $0.49mm^2$ in a $0.13-{\mu}m$ CMOS process.

• Nuclear Engineering and Technology
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• 제30권2호
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• pp.164-172
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• 1998

This paper presents the detailed modelling of reactor vessel ledge region for the dynamic analysis of the coupled internals and core model. The dynamic responses due to earthquake and pipe break are calculated using the input motions of reactor vessel taken from Ulchin nuclear power plant units 3 and 4. Two different representations for detailed and simplified models of the RV ledge region are made. The dynamic responses of the reactor internals components are compared between them. Response characteristics are reported and simplified model is suggested for earthquake and pipe break analysis for the future design of the reactor internals.

• 벤처창업연구
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• 제19권3호
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• pp.173-186
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• 2024

본 논문은 대학에서 결합형 개방형 혁신을 통해 교원 창업을 성공적으로 진행한 사례를 핵심역량이론관점에서 분석해 보았다. 먼저 교원창업의 현 실태를 조망하고, 생성형 AI 기술을 활용한 초실감 3D 가상인간 스타트업인 '오모션(주)'의 사례를 중심으로 서로 다른 전공의 결합형 개방형 혁신의 효과를 탐구하였다. 연구 방법으로는 오모션(주)의 공동창업자들과 기술사업화 담당자, 해당 분야의 전문가들을 대상으로 심층 인터뷰를 실시하였고 근거이론에 따라 이를 분석하였다. 분석에 있어, 본 논문은 핵심역량 이론에 적용하여, 다양한 학문 분야의 전문 지식과 기술이 융합되는 과정을 분석하였다. 이를 통해 본 논문에서는 기존의 단일 기술 중심의 연구 분야로 국한된 교원 창업의 한계를 넘어, 융복합을 통한 고도화와 부가가치 창출의 가능성을 탐색하고, 대학 창업 생태계에 실질적 시사점을 제공하여 교육 및 연구라는 대학의 기존 역할을 넘어서는 경제적 가치 창출 역할을 제시하고자 하였다. 두 교원의 연구를 결합하여 새로운 기술과 비즈니스 모델을 창출하였고, 교원창업으로서 성공적인 결합형 개방형 혁신이 되기 위해서 창업기업은 핵심역량이론 관점에서 (1)기업가적 역량 (2)기술역량 (3)네트워킹 역량을 보유해야 한다는 것을 확인하였다. 본 연구의 시사점은 오모션(주) 사례를 통해 교원 창업의 결합형 오픈이노베이션을 핵심역량이론 관점에서 긍정적인 영향을 미친다는 결과를 도출하였고, 대학에서 창업을 준비하는 구성원을 대상으로 창업의 방향을 제시하였다는 점에 의미를 두고자 한다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2018년도 추계학술대회
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• pp.173-174
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• 2018

This paper proposes the coupled inductor instead of four non-coupled inductors in each leg of the flying-capacitor modular multilevel converter (MMC) to reduce the dimension, weight and cost of the magnetic core. The simulation results have verified the effectiveness of the proposed coupled inductor.

• 한국반도체및디스플레이장비학회:학술대회논문집
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• 한국반도체및디스플레이장비학회 2005년도 추계 학술대회
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• pp.197-202
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• 2005

Due to high permeability of the ferrite core, the characteristics of the ICP are expected to be greatly improved. We investigated the effect of the ferrite cores on conventional inductively coupled plasma. It was observed that the current and voltage in ike ICP antenna are slightly decreased and the power transfer efficiency is increased. However, due to eddy current and hysterisis loss, plasma density in the ICP with the ferrite cores is not increased. It seems that the ICP with the ferrite cores at low frequency (${\~}$100kHz) will be greatly improved since the losses at the low frequency can be negligible.

• Steel and Composite Structures
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• 제7권4호
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• pp.279-301
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• 2007

When coupling beams are proportioned appropriately in coupled core wall (CCW) systems, the input energy from ground motions is dissipated primarily through inelastic deformations in plastic hinge regions at the ends of the coupling beams. It is desirable that the plastic hinges form at the beam ends while the base wall piers remain elastic. The strength and stiffness of the coupling beams are, therefore, crucial if the desired global behavior of the CCW system is to be achieved. This paper presents the results of nonlinear response history analysis of two 20-story CCW buildings. Both buildings have the same geometric dimensions, and the components of the buildings are designed based on the equivalent lateral force procedure. However, one building is fitted with steel coupling beams while the other is fitted with diagonally reinforced concrete coupling beams. The force-deflection relationships of both beams are based on experimental data, while the moment-curvature and axial load-moment relationships of the wall piers are analytically generated from cross-sectional fiber analyses. Using the aforementioned beam and wall properties, nonlinear response history analyses are performed. Superiority of the steel coupling beams is demonstrated through detailed evaluations of local and global responses computed for a number of recorded and artificially generated ground motions.

• Nuclear Engineering and Technology
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• 제55권9호
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• pp.3213-3228
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• 2023

As an important part of the digital reactor, the pin-by-pin wise fine coupling calculation is a research hotspot in the field of nuclear engineering in recent years. It provides more precise and realistic simulation results for reactor design, operation and safety evaluation. CORCA-K a nodal code is redeveloped as a robust pin-by-pin wise neutronics and thermal-hydraulic coupled calculation code for pressurized water reactor (PWR) core. The nodal green's function method (NGFM) is used to solve the three-dimensional space-time neutron dynamics equation, and the single-phase single channel model and one-dimensional heat conduction model are used to solve the fluid field and fuel temperature field. The mesh scale of reactor core simulation is raised from the nodal-wise to the pin-wise. It is verified by two benchmarks: NEACRP 3D PWR and PWR MOX/UO₂. The results show that: 1) the pin-by-pin wise coupling calculation system has good accuracy and can accurately simulate the key parameters in steady-state and transient coupling conditions, which is in good agreement with the reference results; 2) Compared with the nodal-wise coupling calculation, the pin-by-pin wise coupling calculation improves the fuel peak temperature, the range of power distribution is expanded, and the lower limit is reduced more.

• Structural Engineering and Mechanics
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• 제10권3호
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• pp.263-275
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• 2000

In this paper, a core wall structure coupled with connecting beams is discretized and modeled as an equivalent thin-walled member with closed section, while the connecting beams between openings are replaced by an equivalent shear diaphragm. Then, a numerical method (finite member element method, FMEM) for dynamic analysis of the core wall structure is proposed. The numerical method combines the advantages of the FMEM and Vlasov's thin-walled beam theory and the effects of torsion, warping and, especially, the shearing strains in the middle surface of the walls are considered. The results presented in this paper are very promising compared with the ones obtained from finite element method.