• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.44-50
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• 1996

Accumulation of worn-out automobile tires creat fire and health hazards. As a possible solution to the problem of scrap-tire disposal, an experimental study was conducted to examine the potential of using tire chips as aggregate in Railroad block. This paper examines strength and toughness properties of Railroad block in which different amounts of rubber-tire particles of several sizes were used as aggregate. The Railroad block mixtures exhibited lower compressive, bending than did normal block. However, these mixtures did not demonstrate brittle failure, but rather a ductile, plastic failure, and had the ability to absorb a large amount of plastic energy under compressive loads.

• Journal of Ocean Engineering and Technology
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• v.15 no.2
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• pp.130-134
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• 2001

Recently environmental pollution at sea becomes serious, so every governmental organization makes its effort to solve this problem. Combustible ocean wastes as of ropes, fishing nets, and tires are usually highly polymerized compound materials. The problem of ocean waste treatment can be solved by using the pyrolysis method. Pyrolysis characteristics of ocean waste was examined to get the basic data for the production system of fuel from the ocean waste. Thermogravimetric experiment showed that residual mass rate decreases as the velocity of temperature-rising becomes lower. The pyrolysis of waste rope and fishing net occurs at 300~450$^{\circ}C $ and the waste tire does at 350~450$^{\circ}C $. Pyrolysis time is estimated about 15 to 20 minutes in the temperature range when lively act of pyrolysis temperature reached.

• Resources Recycling
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• v.12 no.2
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• pp.28-35
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• 2003

The powder utilization is the one of the best recycling methods for the waste tires. However, economic problem still exist. In order to overcome an economic problem the ground rubber particles are surface modified, which induced to the rubber particles that have good mechanical properties and higher compatibility. In this study, we investigated ultrasonic treatment and reduced rubber particle size. Results showed that sulfur cross-linkage network of the waste rubber is changed by the ultrasonic treatment.

• Journal of the Korean Society for Railway
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• v.4 no.1
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• pp.1-8
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• 2001

In this paper, the dynamics and stability of the automated guideway transit (AGT) vehicles with rubber tires are investigated. Two types of AGT systems are considered: the bogie-type and steering-type systems. The critical speeds for the dynamic instability of lateral and yawing motions are investigated by use of the Routh-Hurwitz's stability criterion. It is shown that the bogie-type AGT vehicles are likely to be stable within the range of practical operating speed, whereas it is not true for the steering-type AGT vehicles. It is also shown that the control performance of steering-type AGT vehicles can be improved by choosing proper steering gains of the closed-loop steering control system.

• International Journal of Control, Automation, and Systems
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• v.6 no.1
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• pp.126-134
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• 2008

As many systems depend on electronics, concern for fault tolerance is growing rapidly. For example, a car with its steering controlled by electronics and no mechanical linkage from steering wheel to front tires (steer-by-wire) should be fault tolerant because a failure can come without any warning and its effect is devastating. In order to make system fault tolerant, there has been a body of research mainly from aerospace field. This paper presents the structure of predictive hybrid redundancy that can remove most erroneous values. In addition, several numerical simulation results are given where the predictive hybrid redundancy outperforms wellknown average and median voters.

• Journal of Industrial Technology
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• v.31 no.A
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• pp.11-19
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• 2011

A new PCD (Pitch Circle Diameter) adjustment system has been designed in this study. Traditional system requires repetitive same works in changing automobile tires. The system proposed in this study requires just one simultaneous work to finish the job. We designed the system using Solidworks CAD software. We further investigate the jobs for both cases through work factor method. Based on careful clarification of the job, work factor units were assigned to each work factor. Even if further analysis should be processed for actual field application, the mechanism proposed in this study may provide good reference for practical usage.

• The Journal of the Acoustical Society of Korea
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• v.13 no.2
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• pp.13-22
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• 1994

A theoretical model is studied to describe the sound radiation by the surface vibration of in-service tires. The tire is modeled as a circular ring model. The effects of normalized frequency and structrual loss factor are included. Through numerical integration of the sound pressure, the radiated sound power is calculated as a fuction of normalized frequency and structural loss factor. The basic sound radiation mechanism is shown to be the damped progressive wave field on the structure in the vicinity of the applied force. The results indicate that the potential sound reduction might be obtained if values of normalized frequency and structural loss factor are investigated.

• Journal of Auto-vehicle Safety Association
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• v.5 no.1
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• pp.50-55
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• 2013

When it comes to commercial vehicles, their unique characteristics - center of gravity, size, weight distribution - make them particularly vulnerable to rollover. On top of that, conventional heavy vehicle brake exhibits longer actuation delays caused in part by long air lines from brake pedal to tires. This paper describes rollover prevention algorithm that copes with the characteristics of commercial vehicles. In regard of compensating for high actuating delay, predicted rollover index with short preview time has been designed. Moreover, predicted rollover index with longer preview time has been calculated by using road curvature information based on environment information. When rollover index becomes larger than specific threshold value, desired braking force is calculated in order to decrease the index. At the same time, braking force is distributed to each tire to make yaw rate track desired value.

• Elastomers and Composites
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• v.55 no.3
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• pp.176-183
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• 2020

Silica-styrene butadiene rubber (Silica-SBR) compounds have been used in the preparation of tire treads. The silica dispersibility of silica-SBR compounds is related to the processability, mechanical properties, and wear resistance of tires. Recently, in order to improve the silica dispersibility of the silica-SBR compounds, the wet masterbatch (WMB) process was introduced, which is a method of mixing rubber in the water phase. We aimed to improve the silica dispersibility of the silica-SBR compounds by preparing a silica dispersant applicable to the WMB process. For this purpose, cellulose, 2-hydroxyethyl cellulose, and cellulose acetate were employed as a silica dispersant. The silica dispersibility of the compounds was measured by a moving die rheometer. Improvement in the processability of silica-SBR compounds was evaluated by the Mooney viscometer. The wear resistance of silica-SBR compounds using a cellulose dispersant was improved by up to 29%.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1535-1540
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• 2008

This paper are using a test apparatus developed in the laboratory, friction and wear characteristics of various rubbers have been analyzed by experimental study. Friction coefficient has been calculated from the measured normal force and friction force under various speed operating conditions, such as, loads and temperatures. The tire are used in a automobile, the relations between the various operating conditions and friction characteristics have been verified.