• 전력전자학회:학술대회논문집
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• 전력전자학회 1996년도 창립기념 전력전자학술발표회 논문집
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• pp.89-92
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• 1996

This paper describes a detailed simulation model of the static condenser (STATCON) to analyze the dynamic interaction with the ac transmission line. The static condenser was represented by a 12-pulse voltage-source inverter sharing an energy storage dc capacitor. The voltage-source inverter consists of two 6-pulse bridges modeled with ideal gate-turn-off switches. The control system for the static condenser was designed through a mathematical model deduced from the equivalent circuit. Simulation results show that the conceived model is very effective to analyze the dynamic interaction between the static condenser and the ac transmission system.

• Interaction and multiscale mechanics
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• 제3권3호
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• pp.257-266
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• 2010

A novel resonance based proximity DC current sensor is proposed. The sensor consists of a piezo sensed and actuated cantilever beam with a permanent magnet mounted at its free end. When the sensor is placed in proximity to a wire carrying DC current, resonant frequency of the beam changes with change in current. This change in resonant frequency is used to determine the current through the wire. The structure is simulated in micro and meso scale using COMSOL Multi physics software and the sensor is found to be linear with good sensitivity.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.115-125
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• 2014

We investigate dissociation of diatomic molecules and anions using density functional theory (DFT) and density-corrected density functional theory (DC-DFT). We scan the potential energy curve of CH, NH and NO neutral molecule and its anion with both DFT and DC-DFT (in form of Hartree-Fock DFT, HF-DFT) using various functionals. Using CCSD(T) results as reference, we perform the error decomposition scheme recently proposed by Kim et al. The results show while most neutrals are $functio{\acute{n}}al$ error $domi{\bar{n}}ating$ normal calculations, $CH^-$ and $NO^-$ anions are density-driven error dominating abnormal calculations. In case of $NH^-$, traditional DFT goes to a wrong dissociation limit indicating abnormality, but both HF-DFT and CCSD(T) results need further investigation due to the kinks on the curve.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제49권4호
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• pp.272-281
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• 2000

This paper deals with the parallel operation of several numbers of PWM converters for a high speed railway train application. Several considerations are made to reduce the transformer interaction which can cause a current control problem in severe case. Also, in this paper, novel control strategy is proposed to achieve a harmonic free primary-side current control under a light load condition using one current sensor independent of the number of converters. In addition, the modified predictive current controller, which is suitable to a digital current controller with a relatively large sampling period, is used. Finally, to verify the system validity, digital control system with TMS320C44 micro-processor and small scale simulator are made and tested.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 하계학술대회 논문집 A
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• pp.446-448
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• 1995

This paper dscribes a detail simulation model with EMTP (Electro-Magnetic Transients Program) which is very effective to analyze the interaction between the ac transmission line and STATCON (static condenser). The SATCON was represented by two voltage-source converters connected in parallel and sharing an energy storage dc capacitor bank. The voltage source converters was modeled with ideal gate turn-off switches. The power system was represented by a detail generator model and a distributed tramnsmission line model for detail performance analyses. Analysis results show that the conceived simulation model is very effective to analyze the interaction between the ac transmission line and STATCON, and to evaluate the performance of STATCON.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2012년도 제38회 춘계학술대회논문집
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• pp.239-243
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• 2012

This paper is concerned with turbulent flow computations using Large Eddy Simulation (LES) and the flow interaction of vortex shedding in a cylindrical duct flow driven by mass blowing through the wall. The purpose is to analyze non-linear combustion characteristics in the presence of vortex shedding generated in a hybrid rocket motor. Experimental studies have shown sudden changes in pressure (referred as a DC-shift), which depend on the strength of vortex strength of incoming flow. The combustion instability because of a sudden change in pressure fluctuations is mainly related with the interaction between vortex shedding. Therefore LES computation on a duct with injected normal blowing was performed to simulate the turbulent flow interactions with the behaviors of vortices and vortex structures along the injected wall.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제10권4호
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• pp.299-308
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• 2004

최근 단백질 및 도메인과 관련된 방대한 양의 데이타들이 인터넷상에 공표되고 축적됨에 따라, 단백질간의 상호작용에 대한 예측 시스템의 필요성이 제기되고 있다. 본 논문에서는 이러한 데이타를 이용하여 계산적으로 도메인 조합 쌍에 기반하여 단백질의 상호작용 확률을 예측하는 새로운 단백질 상호작용 예측 시스템을 제안한다. 제안된 예측 시스템에서는 기존의 도메인 쌍(domain pair)의 제약성을 극복하기 위하여 도메인 조합(domain combination)과 도메인 조합 쌍(domain combination pair)의 개념이 새롭게 도입하였다. 그리고 도메인 조합 쌍(domain combination pair 또는 dc-pair)을 단백질 상호작용의 기본 단위로 간주하고 예측을 시도한다. 예측 시스템은 크게 예측 준비 과정과 서비스 과정으로 구성되어 있다. 예측 준비 과정에서는 상호작용이 있는 것으로 알려진 단백질 쌍 집합과 상호작용이 없는 것으로 추정되는 단백질 도메인 쌍 집합으로부터 각각 도메인 조합 정보와 그 출현 빈도를 추출한다. 추출된 정보들은 출현 확률 배열(Appearance Probability Matrix 또는 AP matrix)로 불리는 배열 구조에 저장된다. 논문에서는 출현 확률 배열에 기반을 두어, 단백질-단백질 상호작용을 예측하는 확률식 PIP(Primary Interaction Probability)를 고안하고, 고안된 확률식을 이용하여, 상호작용이 있는 것으로 알려진 단백질 쌍 집합과 상호작용이 없는 것으로 추정되는 단백질 도메인 쌍 집합의 확률 값 분포를 생성시킨다. 예측서비스 과정에서는 예측 준비 과정에서 얻어진 분포와 확률식을 이용하여 임의의 단백질 쌍의 상호작용 확률을 계산한다. 예측 모델의 유효성은 효모(yeast)에서 상호작용이 있는 것으로 보고된 단백질 쌍 집합과 상호작용이 없는 것으로 추정되는 단백질 쌍 집합을 이용하여 검증하였다. DIP(Database of Inter-acting Proteins)의 상호작용이 있는 것으로 알려진 효모 단백질 쌍 집합의 80%를 학습 집단으로 사용했을 때, 86%의 sensitivity와 56%의 specificity를 나타내어, 도메인을 기반으로 한 기존의 예측 시스템에 비해서 우월한 예측 정확도를 보여주었다. 이와 같은 예측 정확도의 개선은 본 예측 시스템이 상호작용의 기본 단위로 dc-pair를 채택한 점과 분류를 위하여 새롭게 고안하여 사용한 PIP식이 유효했던 것으로 판단된다.

• 한국재료학회지
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• 제26권1호
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• pp.35-41
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• 2016

The electrical transport properties of $La_{0.5}Sr_{0.5}CrO_3$ below room temperatures were investigated by dielectric, dc resistivity, magnetic properties and thermoelectric power. Below $T_c$, $La_{0.5}Sr_{0.5}CrO_3$ contains a dielectric relaxation process in the tangent loss and electric modulus. The $La_{0.5}Sr_{0.5}CrO_3$ involves the transition from high temperature thermal activated conduction process to low temperature one. The transition temperature corresponds well to the Curie point. The relaxation mechanism has been discussed in the frame of electric modulus spectra. The scaling behavior of the modulus suggests that the relaxation mechanism describes the same mechanism at various temperatures. The low temperature conduction and relaxation takes place in the ferromagnetic phase. The ferromagnetic state in $La_{0.5}Sr_{0.5}CrO_3$ indicates that the electron - magnon interaction occurs, and drives the carriers towards localization in tandem with the electron - lattice interaction even at temperature above the Curie temperature.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7335-7338
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• 2013

There is increasing evidence that natural killer (NK) cells play an important role in antitumor immunity following dendritic cell (DC) vaccination. Little is known, however, about the optimal stimulation of DCs by epitopes and NK interactions for cytotoxicity in tumors. In this study, DC cells activated by the HPV16E7.49-57 epitope and LPS were co-cultured with NK cells in vitro, and then used ot immunize mice to study CTL activity of TC-1, which constitutively expresses HPV16E6E7, with an LDH release assay. Cytotoxicity in mice immunized with DC loaded with epitope HPVE7.49-57 vaccine co-cultured with NK was enhanced significantly (p<0.01). In conclusion, talk-across between DC and NK cells enhances their functions, also improving cytotoxicity againsttumor cells, suggesting that activated DC-NK by epitopes has potential application for cancer-specific immuno-cellular therapy.

• 전력전자학회논문지
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• 제16권6호
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• pp.533-541
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• 2011

본 논문에서는 PSCAD/EMTDC 프로그램을 통해 제주 80kV Pilot HVDC 시스템을 구현하고 제어기를 모델링하였다. ac 계통 연계 시뮬레이션을 위해 제주 ac 계통을 축약하였으며, dc 계통 시뮬레이션을 위해 컨버터 변압기, 고조파 필터 및 dc 전송선로의 설계 파라미터를 적용하였다. HVDC 제어기는 컨버터의 운전모드에 따라 인버터 제어기와 정류기 제어기로 나뉘며, 인버터 제어기는 전류제어기, 전압제어기, 소호각 제어기로 구현하였고, 정류기의 제어기는 전류제어기 및 전압제어기로 구현하였다. 인버터와 컨버터의 V-I 특성곡선에 VDCOL을 적용하여 전압에 따른 전류의 의존 특성을 반영하였다. 제어기의 단위 응답, ac 계통 단상 지락 고장, 3상 지락 고장에 대해 시뮬레이션하여 설계한 제어기의 정상상태 및 과도상태시 동특성을 검증하였다.