• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 춘계학술대회 논문집 에너지변화시스템부문
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• pp.149-151
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• 2009

Hybrid electric vehicle has three operating mode, depending on the operation of the engine and electric motor. According to the speed range of BLDC motor, In hybrid traction mode, both the engine and electric motor deliver to drive train. Battery charge mode, the electric motor operates as generator and is driven by the engine to charge the batteries. In engine alone traction mode, the electric motor is do-energized, and vehicle is propelled by the engine alone. we propose hysteresis current control technique to maintain constant speed in the motor load torque at the reverse direction. The proposed method is verified by using Matlab Simulink software.

• Journal of Electrical Engineering and Technology
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• 제1권2호
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• pp.251-256
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• 2006

To design the effective usage of electric double layer capacitors (EDLCs) used for a storage device of dye sensitized solar cell (DSC) energy, we first investigated the accumulation state of electrical charges and the charge behavior in the EDLCs. Based on the results, the voltage characteristics of EDLCs connected to DSC energy were evaluated. The results showed that the charge accumulation region concentrated on the central part of the carbonaceous electrode in EDLCs and the required times for charging and discharging were almost the same.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.673-676
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• 2005

To design the effective usage of electric double layer capacitors (EDLCs) used for a storage device of dye sensitized solar cell(DSC) energy, we first investigated the accumulation state of electrical charges and the charge behavior in the EDLCs. Based on the results. the voltage characteristics of EDLCs connected to DSC energy were evaluated. The results showed that the charge accumulation region concentrated on central part of the carbonaceous electrode in EDLCs and the required times for charging and discharging were almost the same.

• 설비공학논문집
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• 제24권10호
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• pp.733-738
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• 2012

It is important issue to reduce the electric energy to save the operating cost of HVAC system. Even if electrical energy is the clean energy, it is difficult and takes high cost for storage of electricity. These cause the high peak load of electric energy for HVAC in summer season. In korea, government impose the electric charge with several grade for the purpose of cut-off the peak load of electricity. Government has a policy to support to design and install the heat/ice storage system using midnight electricity. In this study, analysis of cooling load and operating characteristics for ice storage system are performed. And, also economical efficiency is compared between ordinary charge system of electricity and midnight rate charge of electricity. The systematic and economical supports are needed for expansion of usage of energy saving equipments.

• Journal of Mechanical Science and Technology
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• 제20권5호
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• pp.681-691
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• 2006

Nucleate boiling heat transfer for refrigerants, R113, and R113+wt4% ethanol mixture, an azeotropic mixture under electric field was investigated experimentally in a single-tube shell/ tube heat exchanger. A special electrode configuration which provides a more uniform electric field that produces more higher voltage limit against the dielectric breakdown was used in this study. Experimental study has revealed that the electrical charge relaxation time is an important parameter for the boiling heat transfer enhancement under electric field. Up to 1210% enhancement of boiling heat transfer was obtained for R113+wt4% ethanol mixture which has the electrical charge relaxation time of 0.0053 sec whereas only 280% enhancement obtained for R113 which has relaxation time of 0.97 sec. With artificially machined boiling surface, more enhancement in the heat transfer coefficient in the azeotropic mixture was obtained.

• Korean Journal of Acupuncture
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• 제27권4호
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• pp.49-57
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• 2010

Objectives : The aim of this study is evaluation for significance of skin meridian-acupoints energy measurement system, and is verification of principle to measure the bio-ion charge on acupoints. Methods : To check a correlation between the MEP(Meridian Energy Potential) and bio-electric charge condition, ten acupoints(left/right BL meridian : BL13, BL15, BL18, BL20, BL23) were chosen. Based on basic theory concerning the upward trend of the bio-electric charge by cupping therapy, we measured MEP change before and after 600mmHg(80kPa) Negative pressure stimulation using cupping. Results : We could identify the correlation between MEP and the condition of bio-electric charge in acupoints. Also, we checked the balance or imbalance of left/right the MEP and unusual cases. Conclusions : We confirmed significance of proposed principle and meridian energy measurement system.

• 한국컴퓨터정보학회논문지
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• 제15권8호
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• pp.157-161
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• 2010

대도시 대기오염의 대부분이 자동차 배출가스에 의해서 이루어지고 있으며, 세계적으로 환경오염에 대한 규제수준이 점차 강화되고 있어 저공해의 환경 친화적인 자동차의 개발과 보급이 요구되고 있으며, 고유가 시대에서 이미 국내 외에서 개발 양산중인 하이브리드 자동차의 급속한 시장 확대가 예상된다. 하이브리드 자동차에서 전기에너지를 저장하는 배터리는 가장 중요한 구성요소 중 하나이며, 하이브리드 자동차용 배터리(전기에너지를 저장하는 2차 전지)는 순간적으로 에너지를 방출하는 특성 즉 고출력 특성이 일차적으로 요구되며, 자동차 부품으로서의 신뢰성과 내구성이 확보되어야 한다. 따라서 본 논문에서는 하이브리드 자동차에 장착되는 2차 전지의 충 방전 상태를 안정적으로 모니터링 하는 시스템과 전지의 충 방전 성능을 극대화할 수 있고 충 방전 제어가 가능한 실시간 충 방전 모니터링 시스템을 제안하였다. 논문에서 새롭게 제안한 감지부와 제어부로 구성되는 충 방전 시스템은 하드웨어 및 소프트웨어 모듈과 실시간으로 셀 배터리의 충 방전 상태를 효율적으로 제어할 수 있으며 데이터베이스와 통신모듈을 기반으로 원격제어가 가능한 시스템이다.

• 한국수소및신에너지학회논문집
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• 제29권6호
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• pp.661-667
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• 2018

Electric vehicles are taken a long time to charge and are restricted driving where charging infrastructure was not sufficiently constructed. The vehicle developed to solve these problems is a plug-in hybrid vehicle. It is possible to drive a certain distance by using electric motor and when the battery runs out, it operate the engine. Plug-in hybrid vehicle have a complicated structure and a lot of parts comparing a general vehicle because the electric parts and the internal combustion engine are installed together. Therefore, as the aging (mileage) of the plug-in hybrid vehicle, the influence which change of fuel consumption is expected to be larger than a general vehicle, but an experimental data are lacking. In this paper, we cumulate a mileage of the plug-in hybrid vehicle about 15,000 km and measured the fuel economy when the cumulated distance reached within 160 km, 6,500 km, 15,000 km respectively, by using domestic public test method. For measuring fuel economy of the vehicle, CD mode (driving distance on a single charge) which use only motor and the CS mode which operate motor and combustion engine were measured respectively. As a result, the fuel economy slightly increased at cumulated mileage of 6,500 km compared to the 160 km and the fuel economy of 15,000 km was similar to 160 km.

• 한국추진공학회지
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• 제10권4호
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• pp.19-25
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• 2006

STS 304 발열선과 $Zr-KCIO_4$ 기폭화약을 사용한 전기식 착화기에 대한 열전이 특성을 시험하고 Fitted Wire Model로 분석한 결과, 약 $300^{\circ}C$ 부근에서 기폭화약과 관련된 열전이 특성 파라미터가 급격하게 변화되었다. 이 현상은 기폭화약에 사용된 $KCIO_4$의 상변화로 인한 흡열반응에 의해 발생된 것으로 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1633-1635
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• 1996

This phenomena of streaming-electrification is generated between solid and liquid boundary called electric double-layer which is generated by potential difference. A charge separation at interfaces between a moving fluid and a solid boundary can give rise to the generation of substantial electric field and at last these can give rise ta insulating failure. Therefore injection of the adverse-charge in streaming-electrified insulating oil to eliminate the accumulation charge and its related phenomena was investigated.