• Journal of KSNVE
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• v.12 no.2
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• pp.113-119
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• 2002

‘인체진동(human vibration)’은 진동에 대한 인체의 반응(human response to vibration)의 줄임말로써, 환경으로서의 진동 및 충격이 인체에 미치는 물리적, 심리적 영향을 측정, 평가하는 것을 주요 연구대상으로 한다. 인체진동 분야의 주요 연구개발은 객관적인 물리량의 산출뿐만 아니라 주관적인 느낌을 수치화하는 작업을 포함하기 때문에 기계진동, 생체역학(biodynamics)과 기본적인 역학과 심리측정학(psychometrics), 심리물리학(psychophysics), 인간공학(ergonomics) 등과 같이 다양한 종류의 학문이 요구된다.(중략)

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.550-553
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• 2009

도로 환경 모니터링을 위한 센서 노드의 전력원으로 유도풍을 이용한 압전에너지 하베스팅 기술은 기존 재생 에너지의 설치 및 작동 조건에 영향을 받지 않고, 도로상에 주오염원인 자동차에서 발생되는 폐에너지를 활용하는 친환경적 에너지 순환시스템을 구현하는 핵심 요소이다. 차량 유도풍에 의해 발생되는 풍압으로 도로 상의 구조물에 진동을 유발한다. 이 때 발생한 진동 에너지는 압전체를 통해 전기 에너지로 변환, 저장할 수 있다. 이렇게 저장된 에너지는 센서의 구동과 무선 데이터 송수신을 위한 센서 노드의 전력원으로 사용함으로써 별도의 전력원이 필요없게 된다. 본 연구에서는 60km/h로 주행하는 한 대의 차량에 의해 2.7m/s의 유도풍이 발생하여 0.6g로 도로 상의 구조물에 에너지를 전달하게 된다. 전달된 에너지가 압전체를 통해 15uJ 전기에너지로 저장된다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.8
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• pp.589-597
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• 2002

In this paper the nonstationary response of accelerating vehicle is firstly obtained by using nonstationary road roughness model in time domain. To get the result of nonstationary response in frequency domain, the maximum entropy method is used for Processing nonstationary response of vehicle in frequency domain. The three-dimensional transient maximum entropy spectrum (MES) of response is given.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.11a
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• pp.409-414
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• 2007

Nowadays, with the advancement of computational mechanics, and vehicle dynamics simulation linked up with virtual testing laboratory(VTL) and virtual proving ground(VPG) technologies has become a useful method for analyzing numerous driving performances and diverse noise/vibration characteristics. In this paper, the analytical vehicle model based on multi-body dynamics theory was developed to investigate the vibration characteristics according to various road conditions. For the purpose, the whole vehicle parameters, each vehicle's part parameter, and part connecting elements such as spring, damper, and bush were measured by an experiment. Also, the vehicle dynamics model, which includes the front suspension, rear suspension, steering, front wheel, rear wheel, and body subsystems has been constructed for computer simulation. With the developed vehicle dynamics model, three forces and three moments measured at each wheel center were applied to evaluate and analyze dynamics and vibration characteristics for miscellaneous road conditions.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.16 no.12 s.117
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• pp.1215-1223
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• 2006

A leaf spring suspension has been widely used since it can carry big load and its simplicity. But one major drawback is the poor ride performance because of the friction in the system and the high stiffness coefficient. To overcome these, an air spring suspension can be used. The air spring suspension system can improve the ride of the heavy vehicle significantly and also it can adjust the height to the loading and unloading. The road tests for the truck with the leaf spring suspension and air spring suspension are performed to compare the ride quality of the two systems. To develop the air spring suspension system tailored to the target truck, chassis development procedure using CAE has been applied.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.332-339
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• 2006

A leaf spring suspension has been widely used since it can carry big load and simplicity. But one major drawback is the poor ride performance because of the friction in the system and the high stiffness coefficient. To overcome these, air spring suspension can be used. The air spring suspension system can improve the ride of the heavy vehicle significantly and also it can adjust the height to the loading and unloading. A truck with the leaf suspension system is modified with the air suspension system and the performance of the vehicle is compared using the suggested method. The existing leaf suspension can be replaced with the air suspension system to improve the performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.576-582
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• 2017

The switching system in a maglev train is an indispensable element for distributing train routes, and it should be designed to ensure safe operation. Unlike conventional wheels on rails, the switching track in EMS-type maglev is supported by a group of 3 to 4 steel girders. When the vehicle changes its route, the segmented track allows the girders to change from a straight position to a curved one with a small radius of curvature. Hence, the structural characteristics of the segmented switching system may affect the levitation stability of the maglev vehicle. This study experimentally evaluates the dynamic interaction between maglev vehicles and a segmented switching system. The results may be helpful for improving the switching system. The measured levitation and lateral air gaps were evaluated at a vehicle speed of 25 km/h, and the ride quality of the Maglev vehicle was determined to be "comfortable" according to the UIC 513 standard.

• Journal of the Korean Society for Railway
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• v.12 no.2
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• pp.230-235
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• 2009

We have conducted an experimental study to analyze characteristics of the wheel profile wear and an influence of the wheel flange wear on the vehicle's vibration characteristics. In experiment with EMU, wheel profile wear is severe at the beginning of the commercial operation. In this stage, the variations of the wheel dimension parameters and equivalent conicity is changed rapidly. Along with a mileage of the test vehicle, the wear of the wheel flange is increased and also the vibration level of the car-body is increased. The peak-peak mean value of the body vibration is estimated as good level, but the level is approached at the limit of the good level as mileage increases. Especially, the peak-peak maximum value of the body vibration shows the distinct increase of vibration level.

• Journal of the Korean Institute of Gas
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• v.19 no.6
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• pp.67-71
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• 2015

Natural frequencies of a cryogenic fuel tank of LNG vehicle were computed to check the safety related to the resonances, and tests were performed to confirm the vibrational durability of a cryogenic fuel tank. There were 3 tests. The first test started at excitation frequency of 31.9Hz, and the test was performed reducing the excitation frequencies. Failure took place at 22.1Hz. The second test was performed with the frequencies to be increased. At 12.7 Hz, failure took place and nitrogen gas was exhausted. In the third test, the excitation frequencies were continuously changed, and the vibration port was failed in the range between 8 Hz and 19.3 Hz. Detailed research on the failed parts of the tank in this study is recommended to enhance the safety of the cryogenic fuel tanks of LNG vehicles.

• Journal of KSNVE
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• v.6 no.3
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• pp.274-285
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• 1996

본 글에서는 대형차량의 엔진 마운트 과정과 마운트 설계시 필요한 사항들에 대하여 간략히 정리해 보았다. 먼저 2장에서는 비교적 형상이 간단한 대형 차량의 마운트 강성을 정확히 설계하는 과정을 제시하였는데, 이 방법에 따라 아운트 재질에 대한 탄성계수를 데이터 베이스화 함으로써 다양한 경우에 원하는 특성을 갖는 마운트를 쉽게 설계할 수 있음을 보였다. 3장에서는 마운팅 설계를 위한 기초 데이터 -관성특성 및 가진력 등에 대하여 기술하였으며, 4장에서는 마운트 최적 설계과정을 정리하였다. 여기서 마운트의 강성을 선정하는 방법과 프레임의 유연성이 엔진 동특성에 미치는 영향을 고찰 최적화하는 과정을 기술하였다. 또한 시혐적 검토에 의한 평가방법을 5장에서 서술함으로 일반적인 엔진 마운트에서의 최적 설계에 대한 내용을 서술하였다.