• Journal of Hydrogen and New Energy
• /
• v.26 no.2
• /
• pp.96-104
• /
• 2015

Reactivity of commercial WGS catalyst and four new catalysts(RMC-3, PC-73, PC-67SU, PC-59) manufactured with various compositions by Korea Electric Power Research Institute(KEPCO RI) were compared to select suitable WGS catalyst for SEWGS system. Steam/CO ratio, gas velocity, flow rates of syngas, and temperature were considered as operating variables. As a result, commercial catalyst showed the highest CO conversion and RMC-3 catalyst showed also high CO conversion. Therefore, commercial and RMC-3 catalysts were selected as applicable catalysts. However, PC-73 catalyst showed low CO conversion at low temperature($200^{\circ}C$) but showed good reactivity at high temperature($225{\sim}250^{\circ}C$), and therefore, PC-73 catalyst was selected as applicable catalyst for high temperature operation. Continuous operations up to 24 hours for those three catalysts(commercial, RMC-3, PC-73) were conducted to check reactivity decay of catalysts. All three catalysts maintained their original reactivity.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.2
• /
• pp.611-627
• /
• 2017

For enhancing the coverage of wireless networks and increasing the spectrum efficiency, small cell networks (SCNs) are considered to be one of the most prospective schemes. Most of the existing literature on resource allocation among non-cooperative small cell base stations (SBSs) has widely drawn close attention and there are only a small number of the cooperative ideas in SCNs. Based on the motivation, we further investigate the cooperative approach, which is formulated as a coalition formation game with power control algorithm (CFG-PC). First, we formulate the downlink sub-channel resource allocation problem in an SCN as a coalition formation game. Pareto order and utilitarian order are applied to form coalitions respectively. Second, to achieve more availability and efficiency power assignment, we expand and solve the power control using particle swarm optimization (PSO). Finally, with our proposed algorithm, each SBS can cooperatively work and eventually converge to a stable SBS partition. As far as the transmit rate of per SBS and the system rate are concerned respectively, simulation results indicate that our proposed CFG-PC has a significant advantage, relative to a classical coalition formation algorithm and the non-cooperative case.

• Bulletin of the Korean Space Science Society
• /
• 1993.04a
• /
• pp.17-17
• /
• 1993

태양의 전자파 복사와 입자의 방출은 지구자기구에 변화를 주어 여러 종류의 플라즈마를 발생시킨다. 관측되는 플라즈마파중에서 주파수가 가장 낮은 영역의 파를 극초저주파수 파동(Ultra Low Frequency pulsation)이라 부르며 주기는 수 초에서 수십 분에 이른다. 본 연구에서는 자기권 내부에 존재하는 플라즈마구 영역(L <5)에서 발생되는 주기가 10 \ulcorner45초인 Pc 3파를 다룬다. 210˚ 자기자오선상에 위치한 Kagoshima(KAG. L=1.22), Chichihima(CBI, L=1.44), Birdsvile(BSV, L=1.57) Adelaide(ADE, L=2.13)관측소에서 1990년 7월27일 잡음정도가 0.1nT rms인 fluxgate 자기계측기를 사용하여 측정하였으며 이 자료를 이용하여 Pc 3파의 Power Spectrurn을 구하고 자기위도 변화에 따른 Pc 3파간의 상관성을 알아본다.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1432-1433
• /
• 2008

Disruption and upset of computer system from intentional unintentional electromagnetic wave is not tenable, if the equipment is used in a security or safety critical application. This paper examines susceptibility of computer network to the HPM. The susceptibility level for PC-systems has been assessed using anechoic chamber. The some failure mode were observed in PC-system. Based on the results, susceptibility of computer network can be applied to database to elucidate the effects of microwaves on electronic equipment.

• Proceedings of the KIPE Conference
• /
• 2010.07a
• /
• pp.204-206
• /
• 2010

기존의 발전용 연료전지 PCS에서는 DC-DC 컨버터가 없이 인버터만 있는 방식이거나 3상 부스트 DC-DC 컨버터에 인버터를 사용하는 방식이었다. 본 논문에서는 6상 부스트 DC-DC 컨버터와 인버터의 구성을 갖는 발전용 연료전지 PCS를 제안한다. 또한 PCS의 운전제어를 위해 제어기간에 CAN통신을 이용하였고 비상상황 발생 시 보호기능을 갖는다. 제안하는 발전용 연료전지 PCS는 시작품을 제작하여 기능과 성능을 검증하였다.

• Journal of ILASS-Korea
• /
• v.7 no.2
• /
• pp.31-36
• /
• 2002

According to the improvement of PC performance, it is expected that calorific value, which causes PC to malfunction, is increased. Therefore, the development of new cooling system is recently required. As the method to solve this problem, we applied loop heat pipe to PC cooling system. The advantage of the loop heat pipe is that it has a small size, light weight, simple shape, long life and it has a good performance on heat transfer, no-noise, wide range of applicable temperature and no supply of power from the outside. It is confirmed that loop heat pipe reduces thermal resistance and has a good performance on PC cooling.

• Proceedings of the KIPE Conference
• /
• 2013.07a
• /
• pp.236-237
• /
• 2013

최근 박막 태양전지에 대한 관심이 증대되면서 이를 이용한 태양광 PCS에 대한 연구가 활발히 진행되고 있다. 박막 태양전지는 모듈의 특성상, 기존의 비절연형 PCS를 사용하여 시스템을 구성하기에 적합하지 않다. 본 논문에서는 승압형 컨버터, 계통 연계형 단상 인버터 2단으로 구성된 비절연형 PCS에 고주파 절연형 컨버터가 추가되어 3단으로 구성된 박막모듈용 3kW급 고주파 절연 PCS를 소개한다. 또한 각종 시험 결과를 통해 적합성 및 성능을 검증하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.10a
• /
• pp.653-656
• /
• 2005

Maglev straight track composes of guide rail, back iron, power rail and girder. Above all, girder is important. So this study analyzes the influence of PC girder and steel girder on stress analysis fur Maglev straight track, and to study the stress analysis the finite element method is utilized.

• Proceedings of the KIPE Conference
• /
• 2015.11a
• /
• pp.107-108
• /
• 2015

본 논문에서는 에너지 저장장치(ESS)용 대용량 PCS 성능검증을 위한 2MW급 성능검증설비의 구축에 대해서 기술하였다. 2MW급 PCS의 성능검증을 위한 시험설비는 피시험용 PCS에 DC전원공급을 위한 배터리 모의장치, 계통 이상에 대한 보호기능 검증을 위한 계통모의장치, 피시험용 PCS의 동작특성, 효율, 전력품질 등을 측정/평가하기 위한 평가시스템, 기타 계통연계설비 및 부하설비로 구성된다. 본 논문에서 기술한 시험설비를 활용하여 당사에서 개발한 2MW급 PCS의 개발검증 외에도 '15년 한전 FR용 ESS 공급사업 관련 당사 2MW급 PCS 인정시험 및 FAT 검수시험에 활용하였다.

• Proceedings of the KIPE Conference
• /
• 2016.07a
• /
• pp.365-366
• /
• 2016

This paper presents a single-phase transformerless photovoltaic (PV) power converter systems based on the AC/DC boost inverter, which is capable of solving the leakage current and second-order ripple power issues. By eliminating the inherent ripple power in single-phase inverter, the bulky electrolytic capacitor can be replaced by a small film capacitor. The validity of the proposed scheme has been verified by the simulation results.