• 한국자동차공학회논문집
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• 제15권5호
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• pp.72-77
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• 2007

Since 2000, sports utility vehicles(SUVs) occupy about 40% of domestic vehicle sales. As sports utility vehicle sales are increased the probability of crash accident between SUVs and passenger vehicles increases. Generally, SUVs are heavier than passenger vehicles and their drive height and front end stillness are higher than passenger vehicles. Because of these characteristics SUVs cause more severe injury and fatal injury in SUV to passenger vehicle head-on impact. To evaluate SUV's aggessivity to passenger vehicle, we carried out SUV to passenger vehicle head-on crash test. And finally the way how to reduce incompatibility between SUVs and passenger vehicles is suggested.

• Industrial Engineering and Management Systems
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• 제6권2호
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• pp.125-135
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• 2007

An automated guided vehicle (AGV) system is a group of collaborating unmanned vehicles which is commonly used for transporting materials within manufacturing, warehousing, or distribution systems. The performance of an AGV system depends on the dispatching rules used to assign vehicles to pickup requests, the vehicle routing protocols, and the home location of idle vehicles, which are called dwell points. In manufacturing and distribution environments which emphasize just-in-time principles, performance measures for material handling are based on response times for pickup requests and equipment utilization. In an AGV system, the response time for a pickup request is the time that it takes for the vehicle to travel from its dwell point to the pickup station. In this article, an exact dynamic programming algorithm for selecting dwell points in a tandem-loop multiple-vehicle AGV system is presented. The objective of the model is to minimize the maximum response time for all pickup requests in a given shift. The recursive algorithm considers time restrictions on the availability of vehicles during the shift.

• 한국철도학회논문집
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• 제2권1호
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• pp.28-37
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• 1999

Many residential areas are situated near to railroad tracks so that a railroad noise has been one of the major environmental issues. In this paper two important aspects have been investigated in order to properly evaluate the railroad vehicle noise : sound power levels for different types and sound propagation characteristics of the railroad vehicles. For noise source characteristics of railroad vehicles, sound power values for various types of trains that are in active service have been measured. In this paper, domestic railroad vehicles are measured and compared with high speed train(TGV). Based on sound power information of railway vehicles, prediction on the sound pressure level and equivalent noise level near to railway areas have been evaluated.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제1권1호
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• pp.1-5
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• 2001

In this paper, we propose a fuzzy traffic controller that is able to cope with traffic congestion appropriately. In order to consider such situation as loss of green time caused by spillback of upper crossroad, it imports a degree of traffic congestion of upper roads which vehicles on a crossroad are to proceed to. We constructed the equal-partitioned fuzzy traffic controller that uses the membership functions of the same size and shape, and modified the size and shape, and modified the size and shape of its membership functions by the membership function modification algorithm. In experiment, we compared and analyzed the fixed signal controller, the fuzzy traffic controller with the membership of the same size and shape, and the modified fuzzy traffic controller by using the delay time, the proportion of entered vehicles to occurred vehicles and the proportion of passed vehicles to entered vehicles. As a result of experiment, the modified fuzzy controller showed more enhanced performance than others.

• 한국수소및신에너지학회논문집
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• 제26권1호
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• pp.35-44
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• 2015

This paper deals with the economic analysis of domestic fuel cell vehicles considering subsidy and hydrogen price in 2015 and 2025. We selected TFCV (Tucson fuel cell vehicle) and TDV (Tucson diesel vehicle) to identify the economic feasibility of fuel cell vehicles compared with conventional internal combustion engine vehicles. We made some sensitivity analysis by changing input factors such as the size of the subsidy, the hydrogen price and the discount rate. Also, we made a break-even point analysis on hydrogen prices that equalize the economic feasibility of TFCV and TDV in 2025. As a result, TFCV is not economical in 2015 due to the relatively high prices of hydrogen and vehicles. If the sale prices of TFCV are 30,000,000 won and 35,000,000 won in 2025, then the break-even points of hydrogen prices are equal to 7,483 won/kg and 5,043 won/kg.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.698-704
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• 2007

Articulated vehicles which have a pivoting joint allowing the vehicle to rotate more easily are difficult to turn the curves because of their long length. In order to review operational safety, turning characteristics related to geometric design should be investigated when articulated vehicles run on the road which can be interfered with other vehicles. The vehicles to review the turning characteristics are the normal articulated bus in Seoul with FWS(front wheel steering) and new bimodal tram with AWS(all wheel steering). Steering characteristics and geometric design were investigated such as turning radius, offtracking, swept path width and swingout. The results were reviewed with respect to the standards of vehicle safety and road design.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.13-19
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• 2007

This study is to establish design method and evaluation technology for drive system appropriate to articulated vehicles. The transmission system of articulated vehicles serves in the other condition compared with those of commercial vehicles, namely, they have to transmit high power to run and they have to make maximum use of the limited space. This paper reports the reviews and results of the design and evaluation method for driving gear unit of articulated vehicles and discusses various design items and methods about assembly and parts of driving gear unit.

• 한국자동차공학회논문집
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• 제22권2호
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• pp.37-43
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• 2014

Exhaust emissions were studied as a function of gasoline olefin composition in two vehicles-MPI and GDi engine equipped vehicles. Three different gasolines were tested which varied in olefin contents-12, 16 and 20 vol%. Exhaust emissions in two vehicles were affected by changes in gasoline olefin composition. Responses to changes in olefins were similar in both vehicles : reducing olefins lowered emissions of NOx and CO. Measured exhaust emissions included total hydrocarbons (THC), oxides of nitrogen (NOx), carbon monooxide(CO), carbon dioxide($CO_2$), formaldehyde, benzene, toluene, xylene, 1,3-butadiene and acetylene.

• 한국대기환경학회지
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• 제11권2호
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• pp.153-162
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• 1995

As exhaust emission standards for new passenger cars amended in 1987 have become more stringent, vehicle manufacturers have employed three-way catalyst in order to meet these requirements. The purpose of this study was to gather informations on new emission control systems in customer use for in-use vehicles from the 1987 through 1992 model years were capable of achieving low exhaust emission levels although high levels do occur due to defects, deterioration or maladjustments with the emission control equipment. The vehicles with closed loop electronic control fuel injection system emitted low exhaust emission, but the carburetor control system equipped vehicles emitted high exhaust emissions and the high mileage vehicles exhibited higher average emissions than low mileage vehicles. It was also found that the useful life of 80, 000km is very important to maintain the low emission levels within customer service period.

• 한국자동차공학회논문집
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• 제5권1호
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• pp.195-206
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• 1997

In this study, a simulation tool is developed in order to investigate non steadystate cornering performance of 4WD/4WS vehicles. The 4WD/4WS vehicles are modeled as a 8-th order dynamic system which includes complex non-linear vehicle dynamics and tire models. The vehicle models are constructed into a modulated simulation tool and are utilized for analyzing cornering performance such as combined braking and steering, cornering on the icy read and $\mu$-split braking, The whole analysis is done with the simulation tool which consists of a number of subsystems and offers graphic environment. Simulation results show that this tool is useful and cost-effective in the dynamic analysis of the combustion-engine vehicles as well as electrically driven vehicles.