• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.87.2-87.2
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• 2011

Many type of fuel cell stacks have been developed to improve the efficiency of reactants usage. The cascade type fuel cell stack using dead end operation is able to attain above 99% usage of hydrogen and oxygen. It is sectionalized to several parts and the residual reactants which are used previous parts would be supplied again to next parts which have less number of cells in dead end operation stack. The oversupply of reactants which is usually 120%~150% of the theoretical amount to generate current for preventing the flooding effect could be provided to each part except the last one. The final section which is called monitoring cells is supposed to be supplied insufficient the fuel or oxidant that would have some accumulated inert gas from former parts. It makes some voltage drop in the part and the fresh reactants must be supplied to the part for recovering it by venting the residual gas. So the usage of fuel and oxidant is depend on the time and frequency of opening valves for venting of residual gas and it is important to optimize the vent logic for achieving higher usage of hydrogen and oxygen. In this research, many experiments are performed to find optimal condition by evaluating the effect of time and frequency under several power conditions using over 100kW class fuel cell module. And the characteristics of the monitoring cells are studied to know the proper cell voltage which decide the condition of opening the vent valve for stable performance of the cascade type fuel cell module.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 추계학술대회 초록집
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• pp.160-160
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• 2010

ELVs (End-of-Vehicles) in Korea incrasease continusely because of increase of used car. Automobile Shredder Residue (ASR) is final product of ELVs (End-of-Vehicles) after recycling. Automobile Shredder Residue are composed of light and heavy fluffs and soil/dust. In this study, 5 ton/day pilot plant of shaft type has been designed and constructed and 15 times of test run were performed. For the stable operation, operation conditions such as the amount of fed ASR and cokes, air flow and temperature in the gasification melting system have been changed and the composition of the produced gas such as $H_2$, CO and $CH_4$ and air pollution compound including dioxin discharged from the stack have been analyzed.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.29-32
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• 2008

Testing was conducted to determine the performance of a residential fuel cell system when subjected to DSS and WSS operation, especially for start-up and shut-down characteristics. In terms of start-up time, it took about 70min to start output power generation and stably to reach 1kW at cold start. Measurement of the characteristics of heat and power generation were carried out at start-up and shut-down time. Fuel gas is used for heating both reformer and stack from start-up to the beginning of power generation. In terms of start-up and shut-down characteristics, it was important to control the reformer temperature precisely. The average output water temperature during the rated output operation(960W) was $63.2^{\circ}C$ constantly. The results of the investigation are being used to develop a new test protocols for residential fuel cell system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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• pp.132-134
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• 2006

This paper presents the design and implementation of 1 kW prototype DC-DC power converter with bridge voltage-doubler suitable for small scale PEM fuel cell system and its associated control scheme. The operation principle of this converter is described using some operating waveforms and the switching mode equivalent circuits based on simulation results and a detailed circuit operation analysis and soft-switching conditions.

• 한국수소및신에너지학회논문집
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• 제18권4호
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• pp.439-445
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• 2007

Proton exchange membrane Fuel Cells(PEMFCs) have been spotlighted because of their broad potential application for potable electrical devices, automobiles and residential usages. However, their utilization is limited to low temperature operation due to the electrolyte dehydration at high temperature. High temperature PEMFC operation offers high CO tolerance and easy water management. This review presents development of high temperature($120{\sim}200^{\circ}C$) PEMFC. Especially, PEMFC which is based on acid-doped PBI membrane is discussed.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.1596-1602
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• 2010

The government have plans to improve the railway transport capacity and transport hub for the sustainable national transport and logistics system. Specially, there are much efforts to improve transportation capacity such as high speed transportation of rail freight, enlargement of BT train, development of double stack train, etc. between railway transport hubs. If the transport capacity between railway logistics hubs is increased as planned, we must increase the handling capacity of railway hub terminals. But there are limits to enlarge the terminal infrastructure because of investment scale, location circumstances and urban development plans. To ensure the capacity, with the minimum required enlargement of infrastructure, it is necessary to extremely increase the efficiency of terminal operations. For improving the efficiency, we have to introduce the efficient terminal operation systems based on u-IT and operation optimize technologies. In this paper, we analyse the issues and problems of railway terminals(including ICD) and suggest the concept of intelligent railway terminal and the construction components of technology.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.135-142
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• 2012

DSRC system is a communication system that consists of road side equipment and on board equipment to provide services of communication technology for intelligent transportation systems. In this paper, we carry out a short-range dedicated high-speed wireless communications via DSRC system based on board equipment that is installed in the vehicle and road side equipment through wireless channels of communication. on board equipment is system that have a memory which initialization information is stored, it loads physical layer and MAC layer, LLC layer, L7 layer in turn. In the upper, it should analyze the various commands that are sent from roadside base stations, and carry out the operation which is in accordance with the command. and also it designs the structure of protocol stack which is TRM Layer loaded that is to initialize on L7 layer and MAC layer and efficiently designs operation between on board equipment and the road side equipment.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.135-138
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• 2009

Quality evaluation of laser welded MCFC separator panels with large active area was performed. Lap joint was applied to produce stable air-tight seam weld by employing Nd:YAG laser. Results showed that surface contamination played a key role to form weld defects at the joint interface. However, there was no evidence that weld width at the lap joint changed after the stack operation time of 2,890h. Test results also revealed that the reinforcement values which were measured on the weld line after long time operation, were stable.

• 대한안전경영과학회지
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• 제12권4호
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• pp.175-181
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• 2010

The government have plans to improve the railway transport capacity and transport hub for the sustainable national transport and logistics system. Specially, there are much efforts to improve transportation capacity such as high speed transportation of rail freight, enlargement of BT train, development of double stack train, etc. between railway transport hubs. If the transport capacity between railway logistics hubs is increased as planned, we must increase the handling capacity of railway hub terminals. But there are limits to enlarge the terminal infrastructure because of investment scale, location circumstances and urban development plans. To ensure the capacity, with the minimum required enlargement of infrastructure, it is necessary to extremely increase the efficiency of terminal operations. For improving the efficiency, we have to introduce the efficient terminal operation systems based on u-IT and operation optimize technologies. In this paper, we analyse the issues and problems of railway terminals(including ICD) and suggest the concept of intelligent railway terminal and the construction components of technology.

• 한국수소및신에너지학회논문집
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• 제14권3호
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• pp.195-206
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• 2003

Polymer electrolyte membrane fuel cells(PEMFC) are very interesting power source due to high power density, simple construction and operation at low temperature. But they have problems such as high cost, improvement of performance and effect of temperature. This problems can be approached using mathematical models which are useful tools for analysis and optimization of fuel cell performance and for heat and water management, in this paper, transient model consists of various energy terms associated with fuel cell operation using the mass and energy balance equation. And water transfer in the membrane is composed of back diffusion and electro-osmotic drag. The temperature calculated by transient model approximately agreed with the temperature measured by experiment in constant current condition.