The belt in the tire components is the special cord between tread and carcass. The belt, which is compose of some steel cord and thin rubber layer, prevent to propagate the crack or external damage from tread and the separation of rubber layer and carcass. The change of belt part such as the density of steel cord, the cutting angle of cord influences on tire performance. In this study, the density of steel cord and the cutting angle of cord are changed and investigated the static/dynamic characteristics(vertical / lateral stiffness, contact length / width / area, harshness) and noise.

The shape of tire footprint is one of the important factor which affects to the performance of tire such as handling, ride and wear. In this study, the effect of the stiffness for tire footprint is investigated. Some tires on the market were selected and tested the vertical stiffness, lateral stiffness by stiffness measuring system. And the contact length, contact width and contact area are tested, too. The contact width and length is reduced by the increase of the tire stiffness. According to the change of the tire stiffness, the leading edge and trailing edge in the footprint have a different shape.

The sound characteristics is changed by the cabin of the car which mount the speaker. Therefore the speaker must be design to consider the cabin of the car. In this study, the mechanical components of the nonlinear speaker model are investigated by measurement. The frequency characteristics of the sound and the sound pressure level for the same size speakers which are adapted to domestic car model(semi-mid size & mid size car) are investigated, too. From the measurement, we can investigate the differences of the sound characteristics and the thiele-small parameter such as force factor, mechanical mass of driver diaphragm, mechanical resistance of driver suspension losses and mechanical stiffness of driver suspension. This means that the speaker design parameters are changed by the car model

The human activity of most what kind of form belongs in the vibration. For example, we listen in order for the eardrum membrane to vibrate and for the light to fluctuate in order and we make see. The breath is relating in the vibration of the lung and walking becomes accomplished in compliance with the periodic oscillatory motion of the arm and the leg. With technical advancement joins in, the vibration of the passenger cars is influencing many in sound arresting and riding in a car feeling of the vehicle. Gradually the field where the vibration isolation and decrement technique automobile plan is important according to being turning out, the necessity of the measurement which the passenger cars vibration is accurate and analysis was augmented.

The automotive speaker is modeld to nonlinear speaker model using the large signal performance measurement. In order to study the characteristics for the mass of cone paper and damper, the mass of the cone paper and damper is changed and the nonlinear parameters of the speaker are studied using the experimental approach. From measurement data, the effect on force factor, compliance(stiffness), resonance frequency, Q-factor is investigated by changing the conpaper and damper.

Tire manufactures have dealt with noise problem by varying the pitch of the tread. The various formulas for the variations are generally determined differently, however. Often these variations are based on a combination of trial and error, intuition, and economics. Some manufactures have models and analogs to test tread patterns and their variations. These efforts, however practical, do not determine the best variation beforehand or guarantee the best results. For this reason it was felt that a general mathematical approach for determining the best variation was needed. Moreover, the method should be completely general, easy to use, and sufficiently accurate. This paper discusses a mathematical method called Mechanical Frequency Modulation(MFM) which meets the above requirements. Thus, MFM pertains to computing an irregular time sequence of events so that the resulting excitation spectrum is shaped to a preferred form. The first part of this paper treats the theoretical basis for computing an optimum variation ; the second part discusses experimental results and simulation program which corroborate the theory.

When the trains are passed the station, a serious force is applied to ground and the caused vibration is propagated to the area of the station by the ground and rocks. The caused vibration brings about the operation interruption of the equipment which is sensitive to the vibration, or will bring about the structural damage of the station. In this study, to investigate the vibrational evaluation of railway station by the train service, the vibration simulation was performed and analyzed the effect of the vibration isolating countermeasure. From the vibration measurement, all trains that passed through the station exceeded the vibration criteria. Therefore, the vibration isolating countermeasure was established and the vibration simulation was performed.

Articulation Index(AI) is the one of the evaluating methods for the interior sound of the automobiles. The AI measures the articulation level of the sound in the vehicle cabin as passengers talk to another. In this study, the effects of AI were investigated according to the various structures of tire. As the structures of tire were changed, the road noise of the vehicle tire was measured using objective measurement. From this measurement data, the AI was calculated. The AI of front is larger than that of rear. Increasing the tread hardness of tire or decreasing the apex height the AI is improved.

Articulation Index(AI) is the one of the evaluating methods for the interior sound of the automobiles. The AI measures the articulation level of the sound in the vehicle cabin as passengers talk to another. In this study, the effects of AI were investigated according to the various structures of tire. As the structures of tire were changed, the road noise of the vehicle tire was measured using objective measurement. From this measurement data, the AI was calculated. The AI of front is larger than that of rear. Increasing the tread hardness of tire or decreasing the apex height the AI is improved.