• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.1000-1003
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• 2014

The primary purpose of this study is to observe the dynamic behavior within a vehicle on chassis dynamometer throughout cleat impact testing with two different constraining setups (Tie-down strap and one point fixation). Throughout this empirical experiment, no outstanding dynamic behavior characteristics are observed between two setups and thus, the performance of the one point fixation device is validated. Neither the interior noise nor acceleration at driver seat rail and knuckle is heavily influenced by two different constraining methods. However, one point fixation is far more advantageous considering its shorter set up time and its capability of measuring traction force with its built in force sensor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.595-595
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• 2008

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계 학술대회논문집(수송기계편)
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• pp.129-133
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• 2005

Vibration transmitted through rolling tire is a major source of road noise in vehicle interior noise on the range of low frequency.($0{\sim}500Hz$) Among various road noises, tire cavity noise has very peak on $200{\sim}250Hz$. And generally it is generated by cavity resonance of tire. In this paper, tire cut-sample is used to calculate the tire cavity frequency. Cavity resonance frequency of tire is measured through vertical/tangential forces at load cell of axle using drum cleat impact. This method is useful to find cavity peak because measured forces do not have complex peaks. And changing the test conditions (air inflation, loads), tire cavity resonance characteristics are identified. Finally, vehicle interior noise is measured as tire/vehicle are changing. As difference of tire vertical force is bigger, interior noise level is higher at cavity frequency. Also we can assume that vehicle sensitivity is important factor at tire cavity noise.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.551-552
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• 2001

온대와 열대의 연안해역에 형성되어 있는 해초지는 해양생태계 중 생산성이 높고, 작은 크기의 해양동물들이 큰 동물들로부터 보호되고 있는 해양환경을 이루고 있다. 특히 본 조사해역인 호주 동북부 해역은 Cleat Barrier Reef과 더불어 열대성 해초가 많이 밀생되어 있어서 많은 동물들이 서식하고 있다. 어류의 먹이습성 연구는 그 어류가 속해 있는 생태계의 기능적인 면을 이해하기 위한 기초자료를 제공한다. (중략)

• 한국소음진동공학회논문집
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• 제25권3호
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• pp.184-190
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• 2015

NVH engineering has become a hot issue due to radical technology changes and development in automotive industry since customers' expectations and needs for their vehicle is taken to a higher level. However, the source identification and quantification of the road noise within a vehicle is still not at the level where it needs to be to meet their expectations due to its' complex transfer path and difficulties in path optimization. The primary focus of this research is on direct force obtaining method at suspension hard points using suspension test rig. Directly obtained forces at suspension to body mounting points are critical and crucial for determining the effects of design changes of the suspension has on road noise performance. Direct force obtaining method has its limitation in sensor installation within an actual vehicle therefore, many has been indirectly calculating forces using full matrix inversion method or dynamic stiffness method. In this study, to circumvent this limitation, a suspension rig is used. Then, the suspension rig is verified through a comparative analysis of its dynamic behavior between the actual vehicle by cleat test on chassis dynamometer.

• International Journal of Automotive Technology
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• 제6권2호
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• pp.149-159
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• 2005

A full nonlinear finite element P185/70Rl4 passenger car radial-ply tire model was developed and run on a 1.7-meter-diameter spinning test drum/cleat model at a constant speed of 50 km/h in order to investigate the tire transient response characteristics, i.e. the tire in-plane free vibration modes transmissibility. The virtual tire/drum finite element model was constructed and tested using the nonlinear finite element analysis software, PAM-SHOCK, a nonlinear finite element analysis code. The tire model was constructed in extreme detail with three-dimensional solid, layered membrane, and beam finite elements, incorporating over 18,000 nodes and 24 different types of materials. The reaction forces of the tire axle in vertical (Z axis) and longitudinal (X axis) directions were recorded when the tire rolled over a cleat on the drum, and then the FFT algorithm was applied to examine the transient response information in the frequency domain. The result showed that this PI 85/70Rl4 tire has clear peaks of 84 and 45 Hz transmissibility in the vertical and longitudinal directions. This result was validated against more than 10 previous studies by either theoretical or experimental approaches and showed excellent agreement. The tire's post-impact response was also investigated to verify the numerical convergence and computational stability of this FEA tire model and simulation strategy, the extraordinarily stable scenario was confirmed. The tire in-plane free vibration modes transmissibility was successfully detected. This approach was never before attempted in investigations of tire in-plane free vibration modes transmission phenomena; this work is believed to be the first of its kind.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2009년도 제40회 하계학술대회
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• pp.1467_1468
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• 2009

지중 케이블의 고정 및 케이블 축력을 지지하는 목적으로 사용하는 케이블용 클리트는 실제로 여러 종류의 외력을 받으며, 이중 케이블 단락 사고시 발생하는 전자력이 가장 큰 영향을 미친다. 본 논문에서는 케이블 단락 사고시 발생 전자력을 계산하고 이 계산치를 바탕으로 클리트의 외력으로 모의하고, 이를 외력방향에 따라 인장시험을 통해 클리트 설계의 적절성을 확인하고자 한다.

• Structural Engineering and Mechanics
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• 제6권5호
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• pp.571-582
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• 1998

Testing of steel roof purlins is usually performed on full scale models in large vacuum test rigs. To undertake a comparison between web cleat connected purlins and flange bolted purlins a series of tests were performed on a 1:4 small scale model vacuum test rig. Various modelling issues need to be addressed to ensure reasonable comparison with actual constructed roof framing methods but still be suitable for an economical comparison between the connection methods. Model test results were supported by, and found to be in reasonable agreement with, deflection predictions from computer models based on finite element methods. This paper discusses the testing methods adopted and the value of small scale model testing programs as a means of obtaining comparisons between framing options.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집A
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• pp.483-488
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• 2001

As the technique of automobile industry is being advanced, the advancement of vehicle ride is being required. In order to achieve this purpose, the study on the vibration which are produced by moving vehicle is carried out actively. In this study, the tire vibration characteristics for passing over a cleat are analyzed. The model is verified against simulations and experiments. The tire is modeled with 7-DOFs (degree of freedom), and the effects of changing tire design parameters are considered. According to the results of analysis, the design parameters that reduce the tire and wheel vibration energy are conducted.

• 대한기계학회논문집B
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• 제25권12호
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• pp.1756-1765
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• 2001

The heat and mass transfer process between the falling liquid desiccant(TEG) film and the air in counter flow at the dehumidifier of desiccant cooling system were investigated. The governing equations with appropriate boundary and interfacial conditions describing the physical problems were solved by numerical analysis. As a result, the effects of the design parameters and the outside air conditions on the rates of dehumidification and sensible cooling were discussed. The results of the dehumidification and sensible cooling rates were compared with those of the cross flow at the same conditions.