• Journal of Biomedical Engineering Research
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• v.6 no.1
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• pp.13-18
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• 1985

A solution scheme for the squeeze film problem using the Newton-Raphson method with a tangential matrix is presented. The integration of elasticity equation is done with the aid of isoparametric elements and the film thickness under a sinusoidal load is obtained. A new squeeze-suction phenomenon which shoㅁvs the possibility oi maintaining fluid film under cyclic positive load conditions is observed for small load and Period and large compliance parameter cases. Thia could be an interesting result in applications like the viscous hydroplaning and the biological joints.

• The tire
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• s.104
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• pp.8-16
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• 1983

타이어가 마모되면 미끄러지기 쉬울뿐 아니라, 위험하다. 특히 과마모된 타이어가 젖은 노면을 주행하게 되면 ,정지거리가 길어지든가 또는 옆으로 미끄러지기 쉬우므로 위험하며, 또 타이어의 수상활주현상(Hydroplaning)이 일어나기 쉽다. 그러므로 본고에서는 날로 더해가는 교통량의 증가로 과마모타이어의 사용률이 늘어나게 됨으로써 교통사고와 직결되는 타이어의 위험부담을 조금이라도 줄여보고자 타이어로 인한 교통사고의 원인분석과 그 대책을 살펴본 것이다. 특히 본고에서는 일본의 전국 교통사고분석관회의에서 발표된 보고서의 자료를 인용하여 마모타이어와 교통사고의 연관성을 분석해 본 것이다. 따라서 본자료는 처음부터 완전한 것은 아니며 앞으로도 계속 연구할 필요가 있을 것으로 보며, 이 기회에 관련업체는 물론, 관계기관에서도 마모타이어로 인한 사고를 미연에 방지할 수 있는 적극적인 대책을 강구해 줄 것을 진심으로 바라는 바이다.<편자 주>

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.144-149
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• 2000

Porous cement concrete was developed to prevent hydroplaning of airway pavement or to reduce noise emission in highway. In has been introduced in domestic since early 1980' and applied to a pedestrian road or bike way. The concrete, however, has problems such as lack of optimized mix design, low strength and deterioration, etc. The purpose of this study is to manufacture porous cement concrete using blast-furnace slag to enhance mechanical properties. The results of this study are as follows; the compressive strength range is 102∼247kgf/㎠, the tensile strength range is 16∼70kgf/㎠, the bending strength range is 43∼70kgf/㎠, and the coefficient permeability range is 6.79 ×10-2∼1.17∼10-1cm/sec. To develope high-performance porous concrete, further studies are needed on optimum mixture of fineness modulus and admixture.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.4
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• pp.173-180
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• 2004

The tread pattern of a tire has an important effect on tire performances such as handling, wear, noise, hydroplaning and so on. However, a finite element analysis of a patterned tire with detailed tread blocks has been limited owing to the complexity of making meshes for tread blocks and the huge computation time. The computation time has been shortened due to the advance in the computer technology. The modeling of tread blocks usually requires creating a solid model using a CAD software. Therefore it is a very complicated and time-consuming job to generate meshes of a patterned tire using a CAD model. A new efficient and convenient method for generating meshes of a patterned tire has been developed. In this method, 3-D meshes of tread pattern are created by mapping 2-D meshes of tread geometry onto 3-D tread surfaces and extruding them through tread depth. Then, the tread pattern meshes are assembled with the tire body meshes by the tie contact constraint. Residual aligning torque and frictional energy are calculated by using a patterned tire model and compared to the experimental results. It is shown that the calculated results of a patterned tire model are in a good agreement with the experimental ones.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.3D
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• pp.223-229
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• 2012

Skid resistance is defined as the friction between pavement surfaces and vehicle tires. Lower skid resistances were observed as the vehicle speeds the water film thicknesses were increased according to the analysis results using computer modeling. The lift force is calculated from the analysis results and depends on vehicle speeds and the water film thickness. A modified IFI(international friction index) skid resistance prediction model was developed to reduce the differences between the IFI resistance prediction model and the actual skid resistance. The correlation analysis results between the IFI prediction model and the actual skid resistance revealed that the $R^2$ using the modified IFI prediction model was 0.64 whereas the $R^2$ using the conventional IFI prediction model was 0.49. This presents the modified prediction model is better than the conventional one. An improved precise prediction model is to be obtained if water film thicknesses are considered in the modified prediction model.