• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.192-194
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• 2006

To elucidate possible challenges for outdoor practical use of dye-sensitized solar cells(DSC), compared with conventional Si solar cells. DSC modules still need the larger area than conventional Si solar modules to attain the same rated output because of lower photoelectron-chemical conversion efficiency. However, using batteries backup systems, the measured data shows that DSCs gathered over 12% more electricity than Si solar cells of the same rated output power in same outdoor condition. Moreover, battery charging time of DSC is about 1 hour faster than same rate of Si solar module. In this paper, 12 single DSC cells prepared for 4 serialized DSC cells was connected in 3 row parallel which have same output power rate of Si solar module. This DSC module was practiced generating characteristic experiment over outdoor daylight condition and applied with PV battery charger by using DC-DC converter. The main advantages of DSC module battery charger as compared with conventional Si solar module one are shorter charge time and lower cost.

• 전력전자학회논문지
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• 제22권4호
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• pp.330-335
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• 2017

Increased fossil fuel consumption causes global warming, environmental pollution, and abnormal climate change. Wind-generated power installation is proposed to solve this problem. Recently, the wind power plant construction case encourages the installation of the energy storage system (ESS) to improve the intermittency of wind power. The maximized ESS operation profits connected to wind power are not generated in the simplest operation pattern of charging at night and discharging at day. The battery charging efficiency improvement should be considered to get more profits. Thus, there is a possibility of increasing ESS operation profits by analyzing the battery AC and DC charging/discharging efficiency and the yearly average sealed maintenance free (SMP) in hours. In this paper, the battery impedance characteristic, AC and DC charging/discharging efficiency, and the yearly average SMP are analyzed. The operation scenario to improve the ESS battery charging efficiency connected to wind power is proposed and verified via simulation.

• 대한안전경영과학회지
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• 제4권4호
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• pp.137-146
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• 2002

In order to investigate the effect of irradiation by $^{60}Co-\gamma$rays as well as the e thermal treatment on the dielectric deterioration in ethylene propylene rubber, insulating material for electric cables used in atomic power plants, charging discharging current, residual built- up voltage and dielectric properties are measu discussed in this study. Variance in the characteristic of relative dielectric constant as a function of tem was observed in relatively high dose of irradiation. Since glass transition tem appeared at tens of degree Celsius below zero, the characteristic is attributed orientation polarization. Dielectric loss is generally increased, with increasing d irradiation in the characteristic of dielectric loss as a function of temperature, No d loss by thermal treatment was observed. Dielectric resistance decreases with increa of irradiation in the characteristic of charging current as a function of temperature be considered that dielectric resistance seems to be recovered by thermal treatm characteristic of discharging current as a function of time in the specimen less ir become similar to that of the unirradiated, when thermal treated. A peak is shown residual built- up voltage as a function of time, and the corresponding time of the shorten as increasing dose of irradiation. It is also observed that the corresponding the peak is lengthened by thermal treatment.

• 농촌계획
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• 제21권1호
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• pp.19-28
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• 2015

As environmental concerns including climate change drive the strong regulations for car exhaust emissions, electric vehicles attract the public eye. The purpose of this study is to identify rural areas vulnerable for charging infrastructures based on the spatial distributions of the current gas stations and provide the target dissemination rates for promoting electric cars. In addition, we develop various scenarios for finding optimal way to expand the charging infrastructures through the administrative districts data including 11,677 gas stations, the number of whole national gas stations. Gas stations for charging infrastructures are randomly selected using the Monte Carlo Simulation (MCS) method. Evaluation criteria for vulnerability assessment include five considering the characteristic of rural areas. The optimal penetration rate is determined to 21% in rural areas considering dissemination efficiency. To reduce the vulnerability, the charging systems should be strategically installed in rural areas considering geographical characteristics and regional EV demands.

• 대한전기학회논문지
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• 제31권11호
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• pp.146-154
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• 1982

This paper proposes a new circuit for the CDI system to have a constant ignition power at the engine speed range of 500 to 7500 rpm and the battery voltage range of 12 to 16 volts in the 4-cylinder automobile. The proposed CDI system has a closed-loop with a PWM DC-DC converter controlled by the error signal between capacitor voltage and reference voltage. In order to decrease the capacitor charging time, the primary winding of ignition coil is made to be shorted during capacitor charging. An experimental suystem is fabricated and the results obtained thereof are found to be satisfactory.

• Journal of Electrical Engineering and Technology
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• 제8권6호
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• pp.1276-1282
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• 2013

This paper proposes a stochastic modeling of plug-in electric vehicles (PEVs) distribution in power systems, and analyzes the corresponding clustering characteristic. It is essential for power utilities to estimate the PEV charging demand as the penetration level of PEV is expected to increase rapidly in the near future. Although the distribution of PEVs in power systems is the primary factor for estimating the PEV charging demand, the data currently available are statistics related to fuel-driven vehicles and to existing electric demands in power systems. In this paper, we calculate the number of households using electricity at individual ending buses of a power system based on the electric demands. Then, we estimate the number of PEVs per household using the probability density function of PEVs derived from the given statistics about fuel-driven vehicles. Finally, we present the clustering characteristic of the PEV distribution via case studies employing the test systems.

• 경영정보학연구
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• 제23권3호
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• pp.177-200
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• 2021

최근 전자지갑, 디지털화폐, 선불포인트, 선불카드 같은 선불전자지급수단의 사용이 점차 증가하고 있다. 선불지급수단은 선 충전, 후 사용이라는 특성이 있다. 본 연구는 선불 충전이 필요한 서비스의 개선에 도움을 주고자, 선불전자지급수단의 온라인 충전 이용의도에 영향을 미치는 요인들에 대하여 기술수용모델을 변형하여 실증적으로 연구하였다. 선불전자지급수단의 온라인 충전 이용의도에 관련된 선행연구가 많지 않아 기존 간편결제와 전자화폐에 대한 연구들을 통해 요인 변수를 도출하였다. 선불 교통카드 사용자를 대상으로 조절효과를 중심으로 온라인 충전의 이용의도를 분석하였다. 연구 결과 독립변수 중에서 '편리성', '보편성', '자기효능감'은 매개변수인 '지각된 유용성'에 정(+)의 영향을 미치는 것으로 나타났다. '지각된 유용성'은 종속변수인 '이용의도'에 유의한 영향을 미치는 것으로 분석되었다. 사용자들의 성별, 인터넷 사용시간, 인터넷 쇼핑 구매빈도, 모바일충전 이용빈도, 교통카드 이용형태 등에 따라서 '지각된 유용성'과 '이용의도'에 조절효과가 유의미하게 나타났다. 시사점으로 선불 서비스의 유용성을 높이는 방향으로 서비스에 대한 개선과 차별화된 마케팅의 필요성을 제안하였다. 다른 요인변수와 조절변수를 추가하여 전자지갑, 간편결제포인트, 디지털화폐 등의 서비스를 대상으로 향후 연구 방향을 제시하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 추계학술대회 논문집 학회본부 B
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• pp.570-572
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• 1999

An equivalent circuit model of vehicle charging-discharging system for simulation is developed. The vehicle electric power system consists of alternator and battery. The alternator must have adequate capacity for providing electric energy to all loads, and the battery supports the alternator by offering insufficient energy when the alternator output energy is not enough. The alternator model is simplified for the use of characteristic curve, which was provided by its manufacturer, and the battery model is separated in charging mode and discharging mode because of its complex characteristics. Developed circuit model is validated by comparing the simulation data and real experimental data.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1988년도 춘계학술대회 논문집
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• pp.60-62
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• 1988

In this study, the characteristic of charging current which flows into the polymer by applying the corona discharge carriers on the polymer surface was measured, so as to investigate the phenomenon of charge injection and movement if injected charge on polymer. Also. the characteristics of discharge current which flows by shorting both sides of corona charged polymers were measured. Experimental results are as follows; The amount of charges injected by corona discharge vary according to the state of surface and the type of carriers, and then the charging current varies according to the properties of injected carriers.

• 자원리싸이클링
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• 제16권2호
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• pp.56-62
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• 2007

본 연구에서는 마찰하전형정전선별법을 적용하여 폐플라스틱 종말품으로부터 회수된 고비중 산물에 대한 재질분리 실험을 수행하였다. 하전장치의 재질선정을 위한 하전특성 연구결과, PP가 고비중 폐플라스틱의 재질분리에 가장 효과적인 하전재질로 확인되어, PP재질을 이용한 cyclone 하전장치를 개발하였다. 본 연구에서 개발된 cyclone 하전장치를 이용한 재질분리 실험결과, 최적 실험조건에서 PET의 품위와 회수율이 각각 98.5%와 86.2%인 결과를 얻어, 종말품 heavy group 폐플라스틱의 재활용을 위한 재질분리 기술을 확립하였다.