• International Journal of Highway Engineering
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• v.12 no.4
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• pp.47-51
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• 2010

A vehicle classification data is essential for traffic road planning and pavement. In this study, the vehicle height, vehicle criteria for classification applied to measure the height of the car driving has devised a way to install equipment. It is capable of measuring the vehicle height was confirmed to field experiments, the measurement system is obtained to the vehicle length and height data. In this experiment, results showed the accuracy of 88.6% compared to classification data using the discriminant function obtained from video replaying. The height of vehicle applying the classification criteria can be utilized to determine the vehicle class.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.5
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• pp.91-99
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• 2010

The center of gravity on vehicle is a fundamentally important point for assessing and measuring the characteristics of vehicle dynamics. Especially, the center of gravity height on vehicles is the closest factor with respect to rollover accidents in a social issue nowadays. In this paper, the center of gravity height in conjunction with vehicle parameters of vehicle weight, driving axle and roof height after measured by vehicle weight and loading location by means of VCGM developed by KATRI with good performance that the accuracy was less than 0.6% and repeatability 0.3% for vehicles being used in the whole world was observed. As a result of study, the location of center of gravity height on vehicle was able to be estimated with only roof height on vehicle.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.6
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• pp.178-186
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• 2002

3-D numerical studies are performed to investigate the effect of the trunk height and approaching air velocities on the pressure distribution of notchback road vehicle. For this purpose, the models of test vehicle with four different trunk heights are introduced and PHOENICS, a commercial CFD code, is used to simulate the flow phenomena and to estimate the values of pressure coefficients along the surface of vehicle. The standard k-$\xi$ model is adopted for the simulation of turbulence. The numerical results say that the height variation of trunk makes almost no influence on the distribution of the value of pressure coefficient along upper surface but makes very strong effects on the rear surface. That is, the value of pressure coefficient becomes smaller as the height is increased along the rear surface and the bottom surface. Approaching air velocity make no differences on pressure coefficients. Through the analysis of pressure coefficient on the vehicle surfaces one tried to assess aerodynamic drag and lift of vehicle. The pressure distribution on the rear surface affected more on drag and lift than pressure distribution on the front surface of the vehicle does. The increase of trunk height makes positive effects on the lift decrease but negative effects on drag reduction.

• Journal of KSNVE
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• v.5 no.2
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• pp.197-206
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• 1995

Microphone array is designed to measure the equivalent source height of vehicle noise. The equivalent source position is defined for an arbirary distribution of acoustic sources above a perfectly reflecting plane and a microphone array for its measurement is developed. The normalized errors of the measured equivalent source heights are defined including the effects of background noise, the geometric near field, and source size. Normalized errors of the measured source heights obtained by a nemerical simulation for each parameter lead to optimization of the microphone spacing and to the design of an array which gives the equivalent source height as a function of frequency. The performance of the designed array is verified using the stationary loudspeaker experiments.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.12
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• pp.961-967
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• 2009

A 3-dimensional numerical investigation of a WIG effect vehicle with DUP (direct underside pressurization) is performed to predict aerodynamic characteristics and the static height stability. DUP can considerably reduce take-off speed and minimize the hump drag while the vehicle accelerates on the water to take off. The DUP of the model vehicle, Aircat, consists of a propeller in the middle of the fuselage and an air chamber under the fuselage. The air accelerated by the propeller comes into the camber through the channel in the middle of fuselage and augments lift by changing its dynamic pressure to static pressure dramatically. However, the air accelerated by a propeller produces excessive drag and reduces static height stability.

• Journal of Multimedia Information System
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• v.6 no.3
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• pp.119-124
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• 2019

In this paper, a method of detecting vehicle plates through depth pictures is proposed. A vehicle plate can be recognized by detecting the plane areas. First, plane factors of each square block are calculated. After that, the same plane areas are grouped by comparing the neighboring blocks to whether they are similar planes. Width and height for the detected plane area are obtained. If the height and width are matched to an actual vehicle plate, the area is recognized as a vehicle plate. Simulations results show that the recognition rates for the proposed method are about 87.8%.

• Journal of Industrial Technology
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• v.22 no.B
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• pp.27-34
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• 2002

3-D numerical studies are performed to investigate the effect of the air dam height and approaching air velocities on the pressure distribution of notchback road vehicle. For this purpose, the models of test vehicle with four different air dam heights are introduced and PHOENICS, a commercial CFD code, is used to simulate the flow phenomena and to estimate the values of pressure coefficients along the surface of vehicle. The standard $k-{\varepsilon}$ model is adopted for the simulation of turbulence. The numerical results show that the height variation of air dam makes almost no influence on the distribution of the value of pressure coefficient along upper and rear surface but makes strong effects on the bottom surface. That is, the value of pressure coefficient becomes smaller as the height is increased along the bottom surface. Approaching air velocity makes no differences on pressure coefficients. Through the analysis of pressure coefficient on the vehicle surface, one tries to assess aerodynamic drag and lift of vehicle. The pressure distribution on the bottom surface affects more on lift than the pressure distribution on the upper surface of the vehicle does. The increase of air dam height makes positive effects on the lift decrease but no effects on drag reduction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.2
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• pp.561-566
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• 2013

This study aims to develop the control system of vehicle height and apply this developed system to common passenger car. The vibration characteristics to affect ride comfort are examined through driving tests. The hydraulic control system of vehicle height is designed by Macpherson type used most commonly at current passenger car. Tests in this study are operated by the vehicle installed with genuine suspension system of Macpherson type, tuning suspension system and hydraulic control system of vehicle height. As vibration characteristics transmitted to vehicle become random types values of PSD(Power Spectrum Density) are compared.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.5
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• pp.133-139
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• 2009

When two cars impact each other, it is usually known smaller vehicle's passenger likely to be more seriously injured than bigger one's. Generally it is known that SUVs and Light Truck Vehicles (LTVs) are bigger and heavier than passenger vehicles and their drive height such as bumper rail and side member, and front end stiffness are higher than those of passenger vehicles. Because of these characteristics the occupants of passenger vehicle struck by SUVs or LTVs are more likely to experience severe injury or fatal injury. To evaluate SUV and LTV's aggressivity to passenger vehicle, SUV to passenger vehicle and LTV to passenger vehicle head-on crash test have been carried out. And finally the way how to reduce incompatibility between SUV and LTV and passenger vehicles is suggested.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.10 no.5
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• pp.47-52
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• 2011

Vehicle classification data are considerably used in the almost all fields of transportation planning and engineering. Highway agencies use a large number of vehicle classification schemes. Vehicles on the national highway are classified by 12-Category classification system, using number of axles, distances between axles, vehicle length, overhang, and other factors. In the case of using existing axle-sensor-based classification counters (that is, 12-category classification system), two-axle vehicles(Class 1 to 4) can be erroneously classified because a passenger vehicle becomes larger and similar with class 3 and 4. In this reason, this study proposes the vehicle classification scheme based on using vehicle height profiles obtained by a laser sensors. Also, the accuracy of the proposed method are tested through a field study.