• 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.

• Journal of Distribution Science
• /
• v.21 no.12
• /
• pp.127-140
• /
• 2023

Purpose: In a situation where the local economy and alley economy are stagnant, efforts to revitalize the role of small business owners need a virtuous cycle system through consumers' consumption power, not just cash support. Research design, data, and methodology: The study site focuses on Daedeok-gu, the first to introduce local currency as a policy. In the case of the store survey, 254 stores out of 300 stores registered with local currency were analyzed, and the consumer survey was conducted on 1,394 out of 1,500 local people using local currency. Statistical analysis was performed using the SPSS. Result: As a result of time-series checking whether local economic activities are carried out smoothly due to the nature of the local currency, the average daily sales of Daedeok-gu increased by 388,980won compared to 2019. This proved through empirical research in the region that local currency played a priming role in bringing opportunities and rehabilitation to the local commercial districts and small business owners. Conclusions: In the monetary function of simply buying and selling value through payment, points supported as incentives can be used as local currency while inducing direct participation in solving social problems, and the concurrent effect of causing problem-solving and regional economic vitality began to sprout.

• International Journal of Contents
• /
• v.18 no.1
• /
• pp.76-84
• /
• 2022

Tidal power generation plays a critical role in reducing greenhouse gas emissions. It uses a tidal force generated by gravitational force between the moon, the earth, and the sun. The change of seawater height generates the tide-generating force, and the magnitude of the change is the tide level. The tide level change has the same period as the tide-generating force twice a day, every 29.5 days, every year, and every 18.6 years. Sihwa Lake Tidal Power Station is Korea's first tidal power plant that began commercial power generation in August 2011 and has been accumulating a large volume of data on electricity production, power generation sales, sluice displacement, and tide levels. The purpose of this paper was to analyze the impact of the inefficiency factors affecting production and the tidal level change on tidal power generation and their characteristics using Sihwa Lake Tidal Power's operational performance data. Throughout this paper we show that tidal power generating operation is accurately predicting the trends of magnitude of tidal force to be periodical for each day. determining the drop to initiate the water turbine generator factoring the constraints on the operation of Sihwa Lake, and reflecting the water discharge through the floodgate and water turbine during the standby mode in the power generation plan to be in the optimal condition until the initiation of the next power generation can maximize power generation.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.25 no.8
• /
• pp.70-81
• /
• 2011

In this paper, a multi-agent control system for DC-coupled photovoltaic (PV), fuel cell (FC), ultracapacitor(UC) and battery hybrid power system is studied for commercial buildings & apartment buildings microgrid. In this proposed system, the PV system provides electric energy to the electrolyzer to produce hydrogen for future use and transfer to the load side, if possible. Whenever the PV system cannot completely meet load demands, the FC system provides power to meet the remaining load. A multi-agent system based-power management and control algorithm is proposed for the hybrid power system by taking into account the characteristics of each power source. The main works of this paper are hybridization of alternate energy sources with FC systems using long and short storage strategies to build the multi-agent control system with pragmatic design, and a dynamic model proposed for a PV/FC/UC/battery bank hybrid power generation system. A dynamic simulation model for the hybrid power system has been developed using Matlab/Simulink, SimPowerSystems and Stateflow. Simulation results are also presented to demonstrate the effectiveness of the proposed multi-agent control and management system for building microgrid.

• Proceedings of the KIPE Conference
• /
• 2016.07a
• /
• pp.191-192
• /
• 2016

본 논문은 전기식 회생 보조 브레이크의 넓은 범위의 입력전압을 가진 전기에너지를 받아서 넓은 범위의 출력전압을 가진 리튬이온 배터리에 충전할 수 있도록 Buck-boost 토폴로지를 제안하고, 배터리와의 절연을 위해 출력 효율이 좋은 LLC 토폴로지를 제안한다. 제안된 2단 구성 회로의 유효성은 실험을 통해 검증되었다.

• Proceedings of the KIPE Conference
• /
• 2011.11a
• /
• pp.201-202
• /
• 2011

Existing AC distribution system lower the efficiency of the commercial power, and also generate the conversion loss of renewable energy. In this study, DC distribution system interconnected with PV system is produced, and it is studied about characteristics of the system through the experiments which are uesd load of 3[kW].

• Journal of the Korean Society for Nondestructive Testing
• /
• v.3 no.1
• /
• pp.31-35
• /
• 1983

AE technology developments directed at nuclear power plant application are reviewed and related activities in Korea are also briefly introduced.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
• /
• 2000.11a
• /
• pp.235-240
• /
• 2000

This paper presents the reasonable method for electric power management through efficient use of electricity. With a rapid of national economics and living standard, electrical energy consumption markedly increased. Especially it is increased electrical energy consumption in commercial buildings and thus an energy conservation through efficient use of electricity became more important.

• Journal of applied mathematics & informatics
• /
• v.35 no.1_2
• /
• pp.1-9
• /
• 2017

In this paper, we investigate the uniqueness problem related to the power of a meromorphic functions sharing a small function with its derivative. The results in this paper improve and generalize some well known previous results.

• Proceedings of the KWS Conference
• /
• 2003.05a
• /
• pp.143-145
• /
• 2003

The purpose of research is to measure power and dynamic resistance value through RMS module. Specially designed RMS-DC hardware module was tested. Its output which is obtained every half cycle was compared with that of commercial weld checker. The results show good agreement and the relative error in the measurement was found to be around 5%.