• Transactions of the Korean Society of Automotive Engineers
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• v.13 no.3
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• pp.35-40
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• 2005

In the present study, the influence of operating conditions on fuel economy for hybrid electric vehicle was analyzed. In order to accomplish this, vehicle speed, engine speed, battery current and voltage, SOC (state of charge),motor speed and torque, generator speed and torque, engine coolant temperature etc. were measured in real time. The tests were carried out under different driving cycles which are urban and highway cycles, KOREA CITY cycle and on-road driving, and also under various operating conditions such as different initial SOC, with or without regenerative braking etc.. Generally, conventional gasoline engines show a poor fuel economy at stop and go driving, because braking energy is wasted and the engine is operated in low thermal efficiency regions. However, in case of hybrid vehicles, higher fuel economy can be obtained because of utilizing the maximum thermal efficiency regions of engine, idling stop of engine, and regenerative braking etc..

• Journal of the korean Society of Automotive Engineers
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• v.6 no.4
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• pp.36-45
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• 1984

The relationship between vehicle driving pattern and fuel consumption in urban area was studied in Seoul along three representative routes using a test car equipped with all the instruments required for recording modes of traffic and measuring fuel consumption. Correlation with idle speed, fuel consumption and CO concentration of car in use was also measured. The average vehicle speed in Seoul was 31.4 km/h and the time spent in different modes was 23.0% in idle mode, 22.5% in acceleration mode, 32.4% in cruising mode and 22.3% in deceleration mode, respectively. Hence, traffic flow was suggested to be relatively smooth. Fuel consumption per unit distance, .phi. was closely related with trip time spent per unit distance, t, and correlation coefficient obtained from the test car was 0.925, and the relationship between .phi. and t was also obtained from the linear regression with the following equation. .phi.=42.87+0.38 t. Idle speed of vehicle in use was mostly adjusted low and cars which were over the permissible standard of CO concentration (4.5%) were 50% or more. As the idle speed decreased, the fuel consumption was decreased, while the CO concentration was increased. Therefore, the decrease of fuel consumption can not be expected with only a decrease in idle speed.

• Transactions of the Korean Society of Automotive Engineers
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• v.5 no.6
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• pp.77-88
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• 1997

The heat rejection to coolant is a dominant factor for building vehicle cooling system such as radiator and cooling fan. Since the vehicle cooling system also has effects on fuel consumption and noise, the study of heat rejection to coolant has been emphasized. However, the study on heat rejection to coolant has been mainly focused on the field that related to the characteristics of combustion and localized heat loss. It is no much of use in design for the entire cooling system because it is focused on such a specific point. In this work, the heat rejection rate to coolant for four different engines are obtained to derive a simple heat transfer empirical formula that can be applied to the engine cooling system design, and it is compared with the other studies. Also, to observe effects of engine operation factors and heat transfer factors on coolant, we measured the metal temperature and the heat rejection rate. The heat rejection to coolant does not depend significantly upon the coolant flowrate, but mainly upon the amount of air fuel mixture and the air fuel ratio as long as the composition of coolant does not change. The reduction of heat rejection to coolant did not effectively improve the fuel consumption, but was mostly converted to raise the exhaust gas temperature and the oil temperature.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.106-112
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• 2008

Modern vehicles require a high degree of refinement, including good drive ability to meet customer demands. Vehicle drive ability, which becomes a key decisive factor for marketability, is affected by many parameters such as engine control and the dynamic characteristics in drive lines. This paper focuses on the simulation of FTP-75 mode which is considered with spark timing control on transient condition. The acceleration is the most important factor for vehicle fuel economy. The retard of spark timing increases in proportion to acceleration. Likewise, bsfc(break specific fuel consumption) which is affected by spark timing also increases in proportion to acceleration. The result of simulation considered transient condition shows 0.3% of error comparing with a test on chassis-dynamometer.

• International Journal of Automotive Technology
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• v.7 no.1
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• pp.9-15
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• 2006

Prediction of the performance of a carbon canister in vehicle evaporative emission control system has become an important aspect of overall fuel system development and design. A vehicle's evaporative emission control system is continuously working, even when the vehicle is not running, due to generation of vapors from the fuel tank during ambient temperature variations. Evaporative emissions from gasoline powered vehicles continue to be a major concern. The objective of this paper is to clarity the flow characteristics and other such fundamental data for the canister during loading and purging are needed, and this data will prove valuable in the development of the canister. This paper is to evaluate the relationship between carbon canister condition and engine performance during engine operation, and the effects of evaporative emissions on the engine performance were investigated.

• Journal of Hydrogen and New Energy
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• v.27 no.1
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• pp.71-82
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• 2016

A fuel cell electric vehicle (FCEV) could be an alternative solution to gasoline powered vehicles. The Korean and Japanese governments have played the midwifery role in the development of the FCEV industry. This study explores the difference in policy goals for FCEV between the two countries. Koreans recognized that FCEV was innovative technology and put forward the notion of technology pre-occupancy. Whereas, the Japanese government discovered that FCEV was one way to apply hydrogen mechanisms, so they identified the supply of hydrogen as one of the industries of interest, and have played the demiurge role. This study suggests that the role of government is to introduce eco-friendly vehicles, using the cases of Korean and Japanese governments, who introduced FCEV to the world first.

• Transactions of the Korean Society of Automotive Engineers
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• v.24 no.5
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• pp.575-580
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• 2016

This paper sought to find a way to improve the fuel consumption rate of a vehicle for the Shell Eco-marathon Asia 2014, with a special focus on the correlation between vehicle dynamics, aerodynamics and chassis weight reduction. In 'KUTY-Eco 1' designed for SEM Asia 2014, a chassis made with an aluminum alloy tube, semi-monocoque structure and a pivot steering system were adopted to reduce weight and to secure better performance. The goals were achieved using computer-aided engineering(CAE) and parameter study. Finally, 'KUTY-Eco 1' was created, the lightest car in the competition's prototype petrol(gasoline) type category. 'KUTY-Eco 1' secured the official record of 142.7 km/liter during the competition.

• Journal of the Korean Society of Industry Convergence
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• v.22 no.6
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• pp.591-598
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• 2019

Today, due to the development of the industrial society, the need for sustainable research and development for energy depletion and environmental protection is increasing. Among sustainable research, remanufacturing is an ideal way to meet environmental and economic aspects. In this paper, we investigated the End-of-Life Vehicle(ELV) in order to find the recovery method of the core which is the preceding stage of remanufacturing. The number of End-of-Life Vehicle is increasing year by year, but the core recovery rate from ELV is still low. Therefore, a methodology to determine the disassembly priority of each part is proposed to increase the core recovery rate. Based on the analysis Table through the disassembly process, the decision rule was selected and the weighted score evaluation Table was completed to complete the disassembly priority system. Finally, evaluation was made on gasoline vehicles to determine priorities.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.2
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• pp.279-287
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• 2012

Recharging battery in electric vehicle takes a quite long time compared with gasoline and diesel vehicle which is a problem, the industries should solve, to introduce the electric vehicle into the market. For this reason, the institutions are suggesting a method replacing the discharged battery to recharged battery which is recharged in the switching center. However, this technology is still required to make clear the controversial issues such as threats to security and identification of users. In this paper, we explore the factors that threats to securities in battery exchange system and define the security requirements of the battery exchange system to solve suggested issues. The results of the research are expected to be the reference in the other studies of electric vehicle field of the commercialization of the battery recharging methods and analysis of the securities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1575-1580
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• 2011

A key factor in the study of hybrid vehicle is to enhance the usability of energy. The paper introduces the monitor and controlling technology of hybrid vehicle that can process the relevant information considering the structure of power system and driving strategies simultaneously, and can monitor its results. This technology, so called HEV algorithm analysis, has been applied to PRIUS THS made by Toyota Co. LTD. This model is adapted to parallel hybrid type. It has a somewhat comlex structure, but has several merits. It's energy loss is lower when conversing. and also it is easily applied to the conventional vehicle having a gasoline engine without any overall changing of its structure, and so on. This monitor and controlling technology is very useful to study on the various driving strategies of hybrid vehicle for maximizing the usability between engine and electric motor.