• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.12
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• pp.2254-2259
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• 2011

The introduction of Personal Rapid Transit (PRT) has been widely discussed in the Korean transportation research field. However, there is no robust criterion to derive the throughput of cars and passengers at PRT stations, which plays a primary role in determining the overall capacity of PRT systems. The present study provided a methodology to rigorously compute the capacity for simple-serial PRT stations with a single platform, considering three decisive factors, i.e., the demand level of incoming cars and outgoing passengers, the station structure, and the operation strategy. A micro-level simulator was developed for the analysis of station capacity. And, by using this, station capacities were presented for various combinations of the decisive factors. In particular, the relationship between capacity and station structure was investigated in detail. Station structure is represented by the numbers of platform berths, input queue berths, and output queue berths. Moreover, both waive rate and waiting time, which represent the level of passenger service, were taken into account when the station throughput was computed.

• Journal of ILASS-Korea
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• v.1 no.2
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• pp.24-32
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• 1996

Most of the research of small engines to date focused on developing spark ignition engines occupied much parts. Recently the number of a small direct injection diesel engine applied in small cars has been increased and considered as a next generation power source for passenger cars because of its high efficiency. Therefore the combustion chamber becomes smaller and the fuel injection pressure goes higher, which makes fuel sprays impinged easily on the combustion chamber walls. When strong swirls are not induced, the fuel may not mix with air because of fuel deposition on the wall. As a positive way, the combustion chamber systems which is using spray wall impaction has been introduced and assessed by an experimental or a simulate manner. In these systems the raised lands are positioned in tile chamber for spray impaction in order to break up the fuel drops into much smaller and direct them into desirable direction. This study addresses to the effects of rho position and size of the raised land or glow plug to help the chamber design using spray wall impaction. The characteristics of the spray impinged on various lands are investigated and compared with each other. Then the chamber shapes are discussed with the characteristics and their proper position and size is proposed in any chamber volume.

• Journal of Korean Society for Atmospheric Environment
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• v.9 no.4
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• pp.320-328
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• 1993

Gaseous pollutants in Namsan Nos. 1, 2, and 3 tunnels and Pukak tunnel were measured along the road by an air-monitoring van from the evening of February 9 to the morning of February 12 in 1993. Average concentrations of pollutants in Namsan tunnels were 9.2-13.5 ppm CO and 0.037-0.047 ppm SO$_{2}$. Average concentrations of SO$_{2}$ in Pukak tunnel was 0.79 ppm, higher than those in Namsan tunnels, due to the traffic of heavy-duty buses and trucks. The pollutant concentrations in Namsan tunnesl could be explained by emission of passenger cars using unleaded gasolin and LPG taxies. Average concentration of NO$_{x}$ in Namsan tunnels was at least 1.1 ppm, estimated from the emission factor of pasenger cars using unleaded gasoline. Pollutant concentrations in Namsan No. 3 tunnel were higher at the exit because of the piston action of air mass in the tunnel provided by the traffic. Fans installed at Namsan and Pukak tunnes could be useful, but their flushing action of ambient air in the tunnel was not clearly observed.d.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.3
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• pp.141-149
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• 2015

In this study, there is an investigation about the sound quality of automotive horn that attached to luxury sedans. In order to define a questionnaire of horn sound quality the factor analysis is conducted. Ten automotive horns are selected for this research and ten passenger cars(nine is luxury sedan and one economy class car). Luxury is used for the questionnaire as an attribute for the sound quality of car horn. The interior noises for ten test cars are recorded and used for the subjective analysis of car horn sound. In the paper, new sound metric for the car horn sound is presented. The new sound metric is used for the objective sound index for the prediction of subjective sound quality of car horn.

• Journal of Applied Reliability
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• v.12 no.2
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• pp.79-90
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• 2012

The torsion beam type of rear suspension has been adopted by most manufactures of small to medium front wheel drive passenger cars. Previous studies analyzed only the load characteristics of CTBA(the coupled torsion beam axle)'s components. This paper analyzed the results of measurement after measuring loads and displacements, angles when a car equipped with the coupled torsion beam axle is driving in various roads. The most important durability factors for CTBA part are the force and direction of rear CTBA trailing arm. If there are design changes, it was difficult to make a sensor and install each time for measuring the trailing arm forces. After analyzing the loading histories between body and chassis, we developed the transformation matrix that can be converted to mutual force. This paper also deals with the analysis of the force behavior through the analysis of the influence and correlation between the body and chassis parts of cars.

• Land and Housing Review
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• v.2 no.3
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• pp.217-226
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• 2011

The Seoul Metropolitan Government is striving to minimize the amount of traffic according to the supply of apartment houses along with the solution of housing shortage for the low income people through high density development near the subway area. Therefore, a stronger policy is necessary to control the traffic of the passenger cars in a subway area for the successful high density development focusing on public transportation, and especially, the estimation of the demand of cars with high reliability is necessary to control the demand of parking such as the limited supply of parking lot. Accordingly, this study developed car ownership forecasting model using Look-up Table among category analyses which are easy to be applied and have high reliability. The estimation method using Look-up-Table is possible to be applied to both measurable and immeasurable types, easy to accumulate data, and features the flexible responding depending on the changes of conditions. This study established Look-up-Table model through the survey of geographical location, the scale of housing, the accessible distance to a subway station and to a bus station, the number of bus routes, and the number of car owned with data regarding 242 blocks in Seoul City as subjects.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.152.1-152.1
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• 2011

This study analyzes transitions to a green path in transportation system in South Korea. We develop transportation system model with four new technology options, green cars; Hybrid electric vehicle, plug-in hybrid vehicle, electric vehicle and fuel cell vehicle. Among those technologies fuel cell vehicle is the best option assuming no GHG emissions when driving. We use MESSAGE model to get an optimal solution of pathway for high deployment of fuel cell vehicles under the Korea BAU transportation model. Among hydrogen production sources, off gas hydrogen is most economic since it is hardly used to other chemical sources or emits in South Korea. According to off gas hydrogen projection it can run 1.8 million fuel cell vehicles in 2040 which corresponds to 10% of all passenger cars expected in Korea in 2040. However, there are concerns associated with technology maturity, cost uncertainty which has contradictions. But clean pathway with off gas and renewable sources may provide a strong driving force for energy transition in transportation in South Korea.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.2
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• pp.212-219
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• 2002

In the frontal collision of cars, front parts of cars such as engine rail and side members that are composed of hatted section tubes should absorb most of the collision energy far the passenger compartment not to be deformed. For these reasons the study on the collapse characteristics, maximum crushing load and energy absorption capacity of hatted section tubes are needed. In this study, top hatted section tubes and double hatted section tubes are investigated. The maximum crushing load of hatted section tubes is induced from plastic buckling stress of plates by considering that the hatted section tubes are composed of plates with each different boundary conditions and that its material has a strain hardening effect. On this concept maximum crushing load equations of hatted section tubes are derived and verified by experiments. from the results of experiment, the differences of collapse characteristics between top hatted section tube and double hatted section tube are analysed. And mean crushing loads of hatted section tubes from experiments are compared with other theory.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.804-805
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• 2006

Electric scroll-compressor drives are commonly used for e.g. home appliance cooling units. The recent development of hybrid cars with internal combustion engine in combination with electrical propulsion requires new solutions to be able to cool the passenger compartment of cars at stand-still. Both application areas demand efficient motor drives to reach good economy and efficient use of limited battery power as well as competitive volume/weight for a given output. The BLDC motor is a controllable and efficient solution. A major part of the motor is the soft-magnetic core. The powder based $Somaloy^{(R)}$ material shows high resistivity and induction as the result of engineered iron particles with in-organic coating. The unique features of compacted $Somaloy^{(R)}$ components can be utilized to enhance the shape and total volume of the BLDC motor with at least maintained efficiency compared to the use of traditional laminated steel sheet cores. A careful design of the $Somaloy^{(R)}$ components can also simplify assembly and positively influence the coil configuration. This study shows a comparison between a typical laminated BLDC motor and a redesigned, $Somaloy^{(R)}$ based version adapted for a scroll-compressor application.

• Journal of ILASS-Korea
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• v.22 no.1
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• pp.8-12
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• 2017

Recently, manufacture and sales of passenger car with GDI (Gasoline Direct injection) were dramatically increased in Korea. In this study, investigation on the exhaust emission characteristics of GDI vehicles according to mileage were conducted by using chassis dynamometer and emission analyzer. Test cars selected 5 types with G4FD engine (1600 cc) and emissions of total 14 vehicles analyzed. Measurement and evaluation on emissions (CO, NOx, NMOG, $CO_2$) characteristics of GDI vehicles with mileages from 40,000 to 80,000 km in certification driving cycle (CVS-75) were carried out in this study. It is revealed that emission results of all test cars shows below emission standard, NMOG emission value of about 80,000 km doubled that of 40,000 km and emission increased by accumulated mileage. Also, increasing pattern of NOx emissions shows when the vehicle mileages was increased and $CO_2$ emission increasing trend obviously do not show according to mileages.