• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.6D
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• pp.605-613
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• 2010

In this study, Impact factors are represented and barrier height of compact car road of safety barrier is suggested through the investigation of applying problems of existed standard of general car road. For this, traffic accidents analysis is performed and based on the analysis, impact vehicle weight, impact Angle, crash velocity, and barrier height are investigated. For the decision of impact angle, analysis is carried out by comparison of RISER and 2-lines expressway accidents data. Through this, higher-impact angle is suggested. Vehicle weight data of sub-compact car, small vehicle, medium and large vehicle, SUV, small truck is surveyed and analyzed. Based on the accident accumulation rate, regression analysis of vehicle weight impact and impact velocity is performed. Also, based on the cumulative rate of vehicle weight on expressways near Seoul, barrier height of compact car road is calculated. It is noted that the results of this study will be contributed to the decision of barrier type.

• The Journal of the Acoustical Society of Korea
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• v.37 no.4
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• pp.248-255
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• 2018

It is known that the road noise on the rear seat of a hatchback type car is worse than that of a sedan type car because of the weakness on sealing structure. Therefore, a sound sealing system and sufficient absorption/insulation performance are required. In the case of a compact segment car, however, the application of the sufficient absorption and insulation materials is limited, because of the restriction on the production cost and weight of the car. In this study, we estimate the noise transmission path on the vehicle's body structure from tires and ground using the PBNR (Power Based Noise Reduction) method which is useful in quantitative measurement. Based on these results, we suggest an alternative absorption/insulation method for the better performance of rear seat road noise reduction in a compact hatchback car.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.10a
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• pp.600-604
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• 2013

A CTBA(Coupled Torsion Beam Axle) is a general type for rear suspension of small/compact sedans. It connects left and right knuckles using torsion beam axle and trails rear wheels. Therefore, a CTBA performs a main role of ride & handing. But, a CTBA suspension has main bending mode around 120Hz and causes road booming noise in the interior of a car. Therefore, the mode control of a CTBA is very important for reducing road noise. In this paper, we optimized the shape of a CTBA to reduce road noise considering R&H performance, simultaneously. The vibration mechanism of CTBA was investigated using ODS(Operational Deflection Shape) and mode shape.

• Journal of Environmental Impact Assessment
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• v.4 no.2
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• pp.131-149
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• 1995

The object of this study is to suggest some alternatives for environmental management towards sustainable urban development of Chongju city in Korea. This study analyses urban environmental indicators (population density, land use, road, park, car, etc.), level of air and water pollution and solids waste generation by comparing Chongju city and other large cities. Some alternatives towards sustainable development in Chongju city would be summerized and suggested as higher concentrated land use(compact city), mixed land use, supply of mass transit, establishment of regional environmental standards, total emission regulation of air and water pollutants, the preparation of Local Agenda21 of Chongju, and the introduction of strategic environmental assessment(SEA) into environmental impact assessment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.4
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• pp.707-714
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• 2016

Active driving safety systems for vehicle, such as the front collision avoidance, lane departure warning, and lane change assistance, have been popular to be adopted to the compact car. For improving performance and competitive cost, FMCW radar has been researched to adopt a phased array or a multi-beam antenna, and to integrate the front and the side radar. In this paper we propose several efficient methods to implement the signal processing module of FMCW radar system using low cost DSP. The pulse width modulation (PWM) based analog conversion, the approximation of time-eating functions, and the adoption of vector-based computation, etc, are proposed and implemented. The implemented signal processing board shows the real-time performance of 1.4ms pulse repetition interval (PRI) with 1024pt-FFT. In real road we verify the radar performance under real-time constraints of 10Hz update time.