• Applied Chemistry for Engineering
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• v.24 no.4
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• pp.344-349
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• 2013

Energy storage system is an energy reservoir which can store the electrical energy produced by the power plant into the chemical energy at the time whenever it needs to use. Accordingly, the energy storage system can help to improve the energy utilization efficiency and the stabilization of the power supply system. In addition, it can cope with the issues of carbon dioxide reduction and depletion of fossil fuel. Lead-acid battery in the secondary battery fields is one of the most developed technologies. It is also economical, reliable storage device. Therefore, the instantiation case of energy storage system using lead-acid battery was investigated for the reference studies.

• YAKHAK HOEJI
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• v.40 no.1
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• pp.10-18
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• 1996

Daunirubicin and doxorubicin analogues (5,7,8,9,) in which the natural amino sugar, daunosamine, is replaced by rhamnopyranosyl or 4'-amino rhamnopyranosyl residues have been p repared. The in vitro cytotoxicity of compound 5 or 7 was similar to that of doxorubicin for P388 murine leukemic cell line. But compound 8 or 9 was less cytotoxic than doxorubicin. When administered intravenously on day 1, compound 9 showed antitumor activity comparable to that of doxorubicin against ip-inoculated L1210 murine leukemia and found to be less toxic than doxorubicin. But the in vivo antitumor activity of compound 7 or 8 was inferior to that of doxorubicin.

• Journal of the Korean Applied Science and Technology
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• v.25 no.1
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• pp.52-57
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• 2008

In the present study, impedance characteristics for AgO-Zn cell at various State-of-Charge (SoC) has been studied. The impedance measurements of AgO-Zn cell at various SoC were made over the frequency range from 100kHz to 10mHz with an amplitude 5mV. The impedance parameters have been evaluated by the analysis of the data using an equivalent circuit and a Non-linear least squares (NLLS) fitting method. The total resistances reflects the SoC of the cell. This indicates that the total resistance is important parameter for predicting SoC of AgO-Zn cell.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.117-118
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• 2007

In this paper, we examined an effect by the binder in titanium dioxide film for dye sensitized solar cell. Binder(PEG and PEO) was added the quantity of 10- 40wt% to commercial $TiO_2$ (P25), Respectively. All of $TiO_2$ film was showed porous structure. but difference of film's porosity could not be confirm. Transmittances of $TiO_2$ film was decreased with the increase of binder's quantity, generally. In case of 20wt%, however, Transmittances of $TiO_2$ film was recoded the highest value. and it measured 1.77 of energy-conversion efficiency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.7
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• pp.525-536
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• 2020

The study data used for the analysis of this study were obtained from the raw data during the 1st survey of the 2nd wave of the 2019 Panel Survey on the Employment of Persons with Disabilities conducted by the Korea Employment Agency for Persons with Disabilities. The results showed that, for regular workers, when there was a fixed term of employment contract, it was more likely that the job was retained for 12 months or longer. For the day laborers, workers without a fixed-term employment contract were more likely to retain their jobs for 12 months longer. This suggests that owing to the types of jobs that did not consider disabilities, people with disabilities were facing difficulties in terms of the options available in their job choices and their self-decisions. Therefore, the state would have to develop more job types and skills for these individuals to expand their career options. The growth in the employment of people with disabilities by small businesses that hire day laborers will depend on the diversification of the employment subsidy, which is again dependent on the size of the businesses.

• Journal of the Korean Society for Marine Environment & Energy
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• v.19 no.3
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• pp.185-193
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• 2016

In this study, the present deployment of the multiple wave energy converters (WECs) in a floating wind-wave hybrid power generation platform was estimated considering the interaction effect among WEC buoys. The interaction processes of multiple buoys were very complex, since scattered and radiated waves from each buoy affected the others in the array. The interaction analysis of the diffraction and radiation problem by the array of WECs was applied by matched eigenfunction expansion method (MEEM). The analytical solutions were compared with the results of numerical calculation based on WAMIT. The overall performance of 24 WECs installed in the hybrid power generation platform was evaluated by the q-factor representing the interaction effect among buoys.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.20 no.2
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• pp.168-175
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• 2008

In this study, we estimated the discharge capacity of Solicheon sluice gate in Gunjang national industrial complex by hydraulic physical scale model test and FLOW-3D. It was showed that the discharge capacity of gate carried by physical model test and numerical analysis was similar.

• Electronics and Telecommunications Trends
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• v.27 no.5
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• pp.18-27
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• 2012

국내외 에너지 정책에 힘입어 LED 조명 보급이 늘어나면서 관련된 광 무선 기술이 주목받고 있다. 적외선 무선통신 포트를 장착한 상용 제품들이 수 년 전부터 공급되었다. 이들이 시장을 주도하지는 못했지만 LED 조명을 이용한 가시광 무선통신은 조명의 커버리지 안에서 안정된 출력과 채널 환경이 매력적이다. 하지만 조명 기능을 우선적으로 유지시켜야 하는 상황에서 광 신호를 다루는 해결책이 충분하지 않아 고속 통신에 제약이 따른다. LED 조명 융합 기술을 무선통신 기술 관점으로 접근하는 새로운 연구가 다양하게 이루어지고 있다. 무선통신은 RF 기반의 시스템이 대부분이지만, 무선 패킷 수요 증가를 고려하여 새로운 주파수 자원에 의한 근거리 무선 보조 수단으로 광 무선통신이 제안되고 있다. 이에 관하여 LED 조명과 연계한 광 무선통신 기술의 현황과 전망을 기술하였다.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.318-320
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• 1996

This paper describes a new dc/ac inverter system, which makes use of parallel loaded high frequency resonant inverter consisting of full bridge, for achieving sinusoidal ac waveform. Because current throughout switch at turn-on is always zero in proposed inverter, low stress and low switching loss is achieved. Operating characteristic of proposed system is analyzed in per unit system using computer simulation. Output voltage of it include low harmonics and almost close tn sine wave.

• Proceedings of the Korean Nuclear Society Conference
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• 1995.10a
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• pp.344-351
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• 1995

증기발생기가 원자로압력용기안에 위치한 일체형원자로의 개발을 위해서 가장먼저 개발되어야 할 요소기술은 관류형 증기발생기의 설계기술이다. 증기발생기는 기존의 상용로에서 사용되고 있는 재순환형 증기발생기와 관류형 증기발생기로 분류 할 수 있는데, U-튜브를 사용하는 재순환형 중기발생기의 경우 습분분리기와 증기건조기 등이 많은 공간을 요구하고 있고, 또한 중기발생기를 압력용기 안에 위치시킬 경우 일차측과 이차측의 냉각수 유로형태, 유동장의 안정성 등의 문제 때문에 일체형원자로에서는 관류형 증기발생기의 도입이 일반화 되어있기 때문이다. 본 연구에서는 관류형(직관 및 나선 전열관형) 증기발생기의 열수력학적 설계 및 성능분석을 위한 프로그램, ONCESG를 개발했다. 개발된 모델링 및 컴퓨터코드의 검증을 위해 외국의 관류형 중기발생기(직관형:미국/영국의 SIR, 나선형:일본의 MRX, SPWR)의 설계자료를 ONCESG프로그램을 사용해 모사한 결과와 이미 발표된 설계자료와의 비교분석을 수행했다. 모사결과 계산된 관류형 증기발생기의 열전달면적, 압력 및 온도분포가 외국의 발표된 설계자료와 잘 일치했으며, 개발된 ONCESG코드를 일체형 신형원자로의 개념설계시 다양한 목적으로 활용할 수 있음을 보였다.