• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.459-463
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• 2002

ER mount can be used instead of rubber mount in cylindrical shell to improve the vibration and noise performance. The noise radiated by cylindrical shell will be reduced by reducing the force transmitted to the cylindrical shell through ER mount. In this paper LQ control theory is used to reduce the transmitted force to the cylindrical shell. The finite element method of cylindrical shell is formulated by NASTRAN and its vibrating shape is calculated in frequency domain. The noise radiated from the cylindrical shell is calculated by the use of SYSNOISE, the boundary element CAE tool. The vibration of the cylindrical shell and radiated acoustic pressure is compared in case of both controlled and uncontrolled ER mount.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.5
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• pp.455-460
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• 2011

In this work, an active hybrid mount using piezostack actuator and rubber element is manufactured, and its vibration control performance is evaluated via feedforward control. A hybrid active mount featuring inertia type of piezostack actuator is proposed and manufactured. After describing the configuration of the hybrid mount, a mount system is then constructed. To attenuate vibrations from vibration sources, a feedfoward controller is experimentally implemented to the system. Vibration control performances are evaluated at each mount. Effective control performances such as accelerations are obtained and presented in frequency domains.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.85-90
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• 2011

In this work, an active hybrid mount using piezostack actuator and rubber element is manufactured, and its vibration control performance is evaluated via feedforward control. A hybrid active mount featuring inertia type of piezostack actuator is proposed and manufactured. After describing the configuration of the hybrid mount, a mount system is then constructed. To attenuate vibrations from vibration sources, a feedforward controller is experimentally implemented to the system. Vibration control performances are evaluated at each mount. Effective Control performances such as accelerations are obtained and presented in frequency domains.

• Composites Research
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• v.13 no.5
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• pp.10-17
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• 2000

The fatigue properties of short nylon66 fiber reinforced Chloroprene rubber have been investigated as functions of interphase conditions and fiber content. The spring constant of rubber decreased about 21% after the fatigue test. On the contrary, that of reinforced rubber increased in all cases. The changing rate of spring constant for reinforced rubber decreased with increasing fiber content. This means that the better interphase condition, the smaller changing rate of spring constant. Temperature of matrix increased about 2.5 times and one of reinforced rubber showed 1.7∼2 times up after the test. The changing rate of temperature for reinforced rubber during fatigue test decreased with increasing fiber content. It is found that the better interphase condition, the smaller changing rate of specimen temperature at the same fiber content. Double coatings of bonding agent 402 and rubber solution became the best interphase model in this study. And, we have investigated the possibility of applying short-fiber reinforced rubber to automotive engine mount rubber, bush and stopper.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.6
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• pp.848-859
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• 2004

Mechanical testing methods to determine the material constants for large deformation nonlinear finite element analysis were demonstrated for natural rubber. Uniaxial tension, uniaxial compression, equi-biaxial tension and pure shear tests of rubber specimens are performed to achieve the stress-strain curves. The stress-strain curves are obtained after between 5 and 10 cycles to consider the Mullins effect. Mooney and Ogden strain-energy density functions, which are typical form of the hyperelastic material, are determined and compared with each other. The material constants using only uniaxial tension data are about 20% higher than those obtained by any other test data set. The experimental equations of shear elastic modulus on the hardness and maximum strain are presented using multiple regression method. Large deformation finite element analysis of automotive transmission mount using different material constants is performed and the load-displacement curves are compared with experiments. The selection of material constant in large deformation finite element analysis depend on the strain level of component in service.

• Composites Research
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• v.13 no.3
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• pp.30-37
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• 2000

The dynamic properties of short-fiber reinforced Chloroprene rubber have been studied as functions of interphase conditions and fiber content. The loss factor generally decreased with fiber content and showed different patterns according to interphase conditions. The better interphase condition showed the lower loss modulus, $E_2$. Also, the dynamic ratio decreased with fiber content and rapidly decreased in the case of double coatings, i.e., model C. Therefore, the short-fiber reinforced rubber could have the better isolation in frequency ratio($\sqrt{2}$ min.) compared to frequency ratio($\sqrt{2}$ max.). And we have investigate the possibility of applying short-fiber reinforced rubber to automotive engine mount.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.6
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• pp.100-106
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• 2012

Recently, the demand to acquire and improve durability performance has steadily risen in rubber components design. In design process of a rubber component, an analytical prediction is the most effective way to improve fatigue life. Existing methods of analytical estimation have mainly used an equation for fatigue life obtained from fatigue test data. However, such formula is rarely used due to costs and time required for fatigue testing, as well as randomness of rubber materials. In this paper, we describe fatigue life estimation of rubber component using only the results from a relatively simple tearing test. We estimated fatigue life of the Janggu type fatigue specimen and the automotive motor mount, and evaluated reliability of the proposed method by comparing the estimated values with actual test results.

• Journal of the korean Society of Automotive Engineers
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• v.10 no.2
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• pp.39-45
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• 1988

The analytical model of an engine mount system with six degrees of freedom is identified using the modal parameters obtained from the experimental modal analysis. The structural parameters, mass moment of inertia of the engine block and stiffness of the rubber mounts, of the engine mount system are determined by using the condition that the estimated model parameters should satisfy the corresponding eigenvalue problem. The simulated modal parameters of the identified analytical model are in good agreement with the measured modal parameters.

• Journal of KSNVE
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• v.7 no.4
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• pp.681-688
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• 1997

The purpose of engine mount system is to reduce the noise and vibration caused by engine vibration, and to decouple the roll and bounce mode at idle. To reduce the noise and vibration level in a vehicle, it is important to make the design optimization of engine mount system that consider the moment of inertia and inclination of mount rubber. As a result, according to the definition of Torque Roll Axis (TRA), the vibration axis at idle must be on the TRA or very close to it. In this paper, we studied the effect of the design optimization of engine mount system. And we have achieved good improvements in noise and vibration quality of F.R. vehicle.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.5
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• pp.129-137
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• 2002

Elastomers, which are used engine mounts and body mount rubbers, are traditionally designed for NVH use in vehicles, and for vibration isolation in specific frequency range. According to the measurement of the characteristics of the SUV's engine mounts, there are variability in same engine mount properties. Static and dynamic stiffness of the SUV's engine mounts are changed due to the driving miles accumulated. The pre-load of body mount rubbers are changed due to the empty vehicle weight, passenger's weight and gross vehicle weight. And the dynamic stiffness of body mount rubbers are changed very hard above 150Hz frequency range.