• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.371-376
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• 2003

The objective of this paper is to compare the site-to-site variability of ISO 10844 pass-by-noise test sites. In order to investigate the site-to-site variance of test surfaces, European commercial tires are tested at seven different test sites. Three Korea test sites and four Europe test sites are selected.. The pass by noise test is executed according to a 2001/43/EC regulation. A]though the ISO surface has a very specific track composition, it does not reduce the variation of pass-by-noise measurements over the surface of test sites. This paper shows that the test results of pass-by-noise level are different depending on the test sites. The correlation obtained in this work is able to predict the pass by noise level for certain test site using the data measured from another test site. 17he prediction value is range with an error within 1dB(A).

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2013.04a
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• pp.623-625
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• 2013

Tire hydroplaning is one of the most important tire performances, especially for safety on wet road surface. And nowadays various methods such as FEM and FVM analysis are being applied to design and improve tire hydroplaning performance, along with on-vehicle test of tire hydroplaning. Conventional evaluation of tire hydroplaning has been done by comparing peak lateral acceleration and vehicle speed in time domain. But in this paper, frequency domain analysis of lateral acceleration when hydroplaning at high speed has been carried out to get the quantitative comparison between test tires. And it is concluded that the frequency spectrum analysis of lateral acceleration gives much better discrimination, as compared to the conventional time domain analysis of lateral acceleration and vehicle speed.

• Tribology and Lubricants
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• v.23 no.5
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• pp.228-233
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• 2007

This paper presents the case studies on the friction related wears of an automotive tire, which is strongly connected to the safety and comfort of a driver during a running of a car. Wear scars of a tire tread are affected by various causes such as an air pressure, a wheel alignment, a driving speed, road conditions, starting and braking habits of a driver. The data were collected from used tires for a replacement at the car service center. Most of the wear problems came from the improper repair and adjustment of revolving components, which cause an unbalanced wear of a tread part of a tire. Thus, the regular checking of a tire radically reduces the wear scars of a tire and may increase a driving safety and a fuel economy of a car and a wear life of a tire.

• Transactions of the Korean Society of Automotive Engineers
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• v.17 no.3
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• pp.102-109
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• 2009

The stumble (abrupt and big acceleration decrease) occurring in manual transmission vehicle while standing start is analyzed by simulation model. This model was verified by comparing to test results. Mechanism of the stumble is clarified by analyzing simulation results and the key mechanism of the stumble is angular vibration of powertrain including wheel and tires. As a result, several method that can reduce the stumble is proposed by carrying out parametric study, increasing low end torque of engine, increase gear ratio etc.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.5
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• pp.188-195
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• 2000

This study was conducted to develop the mathematical model and the computer simulation program(TPPMWV) for predicting the tractive performance of off-road wheeled vehicles operated on various soil conditions. The model takes into account main design parameters of a wheeled vehicle, including the radius and width of front and rear tires, the weight of vehicle, wheelbase and driving type(4WD, 2WD). Soil characteristics, such as the peressure-sinkage and shearing characteristics and the response to repetitive loading, are also taken into consideration. The effectiveness of the developed model was verified by comparing the predicted drawbar pulls using TPPMWV with measured ones obtained by field tests for two different driving types of wheeled vehicle. As a results, the drawbar pulls predicted by the TPPMWV were well matched to the measured ones within the absolute errors of 5.25%(4WD) AND 9.42%(2WD)for two different driving types, respectively.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.11a
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• pp.88-91
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• 1993

유동층 반응기 (H=0.8 m, ID=0.08 m) 에서 폐타이어의 열분해를 수행함에 있어 열분해에 사용되는 열을 외부에서 공급함과 동시에 일부는 내부에서 자체적으로 연소시켜 열을 얻고자 하였다. 온도 증가에 따라 가스의 수율은 40 %까지 증가하였고, 반면에 오일의 수율은 감소하였다. 또한 가스중에 heavy hydrocarbon 이 감소함과 동시에 H$_2$ 및 light hydrocarbon 이 증가하였고 이로 인해 가스 부피당 발열량은 감소하는 것으로 나타났다. 가스의 체류시간도 가스조성에 상당히 영향을 미치는 것으로 나타났으며, 본 시스템에서 발열량 및 가스생성량은 2 u$_{mf}$ 에서 최소치를 나타내는 것으로 보였다. 또한 $O_2$ 농도의 증가는 결국에는 생성가스의 연소를 일으키며, 적당한 $O_2$ 농도의 설정으로 이의 연소를 최소화하는 작업이 필요하다.

• Structural Engineering and Mechanics
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• v.22 no.5
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• pp.517-539
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• 2006

Friction problems involving rubber components are frequently encountered in industrial applications. Their treatment within the framework of numerical simulations by means of the Finite Element Method (FEM) is the main issue of this paper. Special emphasis is placed on the choice of a suitable material model and the formulation of a contact model specially designed for the particular characteristics of rubber friction. A coupled thermomechanical approach allows for consideration of the influence of temperature on the frictional behavior. The developed tools are implemented in the commercial FE code ABAQUS. They are validated taking the sliding motion of a rubber tread block as example. Such simulations are frequently encountered in tire design and development. The simulations are carried out with different formulations for the material and the frictional behavior. Comparison of the obtained results with experimental observations enables to judge the suitability of the applied formulations on a structural scale.

• Journal of Power System Engineering
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• v.4 no.1
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• pp.51-59
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• 2000

Active suspension systems have been using for improving ride quality and stability for vehicles. An active suspension system is composed of a hydraulic pump, pressure control valves, hydraulic dampers, vehicle body, tires and other components. In this study, the mathematical model for the active suspension system based on the quarter car concept is derived, and a program for analysing the dynamic behaviour of the suspension system is developed. The computed results by the developed program are compared with the experimental results for confirming the reliability and usefulness of the developed program.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2007.10a
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• pp.124-127
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• 2007

In this study, we focused on investigation of governing parameters affected on the fatigue properties in the hyper-eutectoid steel wires used for TBR tires. Steel wires are fabricated under different drawing strain from 3.36 to 3.80. Their diameters are 0.21 mm and 0.185mm, respectively. The fatigue properties was measured by hunter rotating beam tester, specially designed thin-sized steel wires. The results showed that the fatigue properites of steel wire, marked as A-1, were greater than the others, due to the low value of residual stress. In order to elucidate the variations of fatigue properties, the microstructure, surface defect and residual stress were observed and measured by useful analysis technique, such as TEM, 3D profiler and FIB.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.6
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• pp.71-80
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• 1994

The purpose of this paper is to explore the use of fuzzy set theory for image processing and analysis. As an application example, the fuzzy method of edge detection is proposed to extract the edges of raised characters on tires.In general, Sobel, Prewitt, Robert and LoG filters are used to detect the edge, but it is difficult to detect the edge because of ambiguity of representations, noise and general problems in the interpretation of tire image. Therefore, in his paper, the fuzzy property plane has been extracted from the spatial domain using the ramp-mapping function. And then the ideas of fuzzy MIN and MAX are applied in removing noise and enhancement of the image simultaneously. From the result of MIN and MAX procedure a new fuzzy singleton is generated by extracting the difference between adjacent membership function values. And the edges are extracted by applying fuzzy $\alpha$-cut set to the fuzzy singletion, Finally, these ideas are applied to the tire images.