• 한국철도학회:학술대회논문집
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• 한국철도학회 2006년도 추계학술대회 논문집
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• pp.294-299
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• 2006

Korean high speed train(HSR-350x) has adopted a combined electrical and mechanical(friction) braking system. Brake blending control unit(BBCU) controls each brake system to fulfill the required brake performances such as braking distance, deceleration and jerk. When the disc brake is applied in the high speed region, the wear of pad is increased rapidly. In this paper, we discuss the optimized patterns of the disc brake force from the view point of braking energy.

• 센서학회지
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• 제13권3호
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• pp.244-251
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• 2004

In general, the braking system of high speed train has an important role for the safety of the train. To stop safely the train at its pre-decided position, it is necessary to combine properly the various brakes. Korean high speed train (HSR 350x) has adopted a combined electric and mechanic (friction) braking system. Electric brakes are consist of rheostatic brake, regenerative brake and eddy current brake and mechanical brakes are composed of disc brake, wheel disc brake and tread brake. In this paper, the measuring method that can take a measurement of the braking forces for disc brake and wheel disc brake has been suggested and we have verified that this method is valid through on-line test of HSR 350x.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.2249-2257
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• 2010

This paper describes the method of how to improve the probability of the tracing stopping ratio which is the most important factor in Automatic Train Operation (ATO). Aspects of improving the performance of automatic driving, the followings are investigated and studied : Brake system maintanence method of vehicle, the need to improve braking system, test method of blending brakes, how to minimize the delay of commands for real-time control. In this study, we applied this method to prove the effectiveness in DAEJEON LINE1.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 춘계학술대회논문집
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• pp.212-217
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• 2004

In general, the braking system of high speed train has an important role for the safety of the train. To stop safely train at its pre-decided position, it is necessary to combine properly the various brakes. The prototype of Korean high speed train (KHST) has been designed, fabricated and tested by the domestic researchers. It has adopted a combined electrical brakes, such as rheostatic brake, regenerative brake and eddy current brake, and mechanical brakes composed of disc brake, wheel disc brake and tread brake. In this paper, the performances and control algorithms of braking system have been reviewed by the experimental method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.103-109
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• 1999

The object of the study is to propose the control method of FSB(full service brake) for the standard EMU. Recently, the variable control function was applied to train by introducing the TCMS. When the vehicle in the train fails, the emergency brake of the train should be automatically operated. In case of VVVF EMU operated by the TCMS, the FSB is applied to the train for safety instead of emergency brake. When the FSB is applied to train regardless of its weight and the numbers, the train safety operation may not be obstained. Therefore, the FSB force which considers its weight and numbers should be applied to the train. This paper describes the blending brake control for standard EMU. The control algorithm of the FSB is proposed and its simulation was carried out by using MATLAB.

• 대한기계학회논문집B
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• 제32권8호
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• pp.582-588
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• 2008

An experimental investigation was conducted to investigate the effect of Bio-ethanol fuel on the engine performance and exhaust emission characteristics under various engine operating conditions. To investigate the effect of bio-ethanol fuel, the commercial 1.6L SI engine equipped with 4 cylinder was tested on EC dynamometer. The engine performance including brake torque, brake specific fuel consumption, and barke specific energy consumption of bio-ethanol fuel was compared to those obtained by pure gasoline. Furthermore, the exhaust emissions were analyzed in terms of regulated exhaust emissions such as unburned hydrocarbon, oxides of nitrogen, and carbon monoxide.Result of this work shows that the effect of blending of ethanol to gasoline caused drastic decrease of emissions under various operating conditions. Also, improved engine performance such as brake torque and brake power were indicated for bio-ethanol fuel.

• 한국수소및신에너지학회논문집
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• 제34권6호
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• pp.767-772
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• 2023

In this study, combustion experiments were conducted at various engine speeds under full-load conditions using a single-cylinder diesel engine by blending butanol, pentanol, and octanol with diesel at a volume ratio of 10%. Experimental results revealed that higher alcohol-diesel blends resulted in lower brake torque and brake power than pure diesel due to the lower calorific value and the cooling effect during evaporation. An evident improvement in the brake thermal efficiency of the blended fuels was observed at engine speeds below 2,000 rpm, with the butanol blend exhibiting the highest thermal efficiency overall. Furthermore, the brake-specific fuel consumption of the higher alcohol-diesel blends was lower than that of pure diesel at speeds below 2,200 rpm. When using blended fuels, the exhaust gas temperature decreased under lean mixture conditions due to heat loss to the air and the cooling effect from fuel evaporation.

• 한국산학기술학회논문지
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• 제14권2호
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• pp.822-827
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• 2013

본 논문에서는 정지시까지 전기제동을 하는 축소모형 추진시스템을 설계하고 제작하여 실험하였으며, 정지순간 제동토오크의 제어방법을 제안하였다. 또한, 레졸바를 사용한 회전자의 위치와 속도를 추정하는 관측기에 의하여 극저속에서 속도를 검출하는 방법을 개발하였으며, 또한 정지순간 제동 토오크의 감소와 동시에 공기 브레이크의 동작을 개시하여 블렌딩 제동을 사용하는 방법과 비교하여, 정지시까지 전기제동만을 사용하는 향상된 제동방법을 제안하였다.

• 한국수소및신에너지학회논문집
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• 제35권1호
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• pp.97-104
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• 2024

In this study, combustion experiments were conducted to assess engine performance and exhaust gas characteristics using four blends of 1-pentanol and diesel as fuel in a naturally aspirated 4-stroke diesel engine. The blending ratios of 1-pentanol were 5, 10, 15, and 20% by volume. The experiments were carried out under four different engine torque conditions (6, 8, 10, and 12 Nm) while maintaining a constant engine speed of 2,000 rpm for all fuel types. The results showed that the use of 1-pentanol/diesel blended fuel generally led to a decrease in brake thermal efficiency, attributed to the low calorific value of the blend and the cooling effect due to the latent heat of vaporization. Additionally, both brake specific energy consumption and brake specific fuel consumption increased. However, the use of the blended fuel resulted in a general decrease in NOx concentration, a decrease in CO concentration except some conditions, and a reduction in smoke opacity across all conditions.

• 한국자동차공학회논문집
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• 제16권2호
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• pp.43-48
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• 2008

The exhaust emissions of diesel engine are recognized as a major cause influencing environment strongly. In this study, the possibility of biodiesel fuel and oxygenated fuel(dimethoxy methane; DMM) was investigated as an alternative fuel for a naturally aspirated direct injection diesel engine. The smoke emission of blending fuel(biodiesel fuel 90vol-%+DMM 10vol-%) was reduced approximately 70% at 2500rpm, full load, in comparison with the diesel fuel. But, power, torque and brake specific energy consumption showed no significant differences. But, NOx emission of biodiesel fuel and DMM blended fuel increased compared with commercial diesel fuel due to the oxygen component in the fuel. It was needed a NOx reduction counterplan that EGR method was used as a countermeasure for NOx reduction. It was found that simultaneous reduction of smoke and NOx emission was achieved with BDF(95 vol-%) and DMM(5 vol-%) blended fuel and cooled EGR method(15%).