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.

This research has been studied a quality management method of silicon wafers for solar cells using the time series analysis. The model which can forecast conversion efficiency in state of a silicon wafer of a solar cell was presented newly and studied its limits. The first approach analyzed correlation between quality characteristics which was currently known and the quality of the last production. Also, The special factor which was unknown to a general factor until now was found. This paper presented the time series analytical model which was transformed in order to forecast exactly the influence that these special quality characteristics were immersed in to the conversion efficiency of cells. Using the correlation of forecasted value along the arbitrary change of measured value, the most optimized reduction factor for calculation of weight to be suitable for this model was defined.

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.

Bonding glasses is one of the important PDP (Plasma Panel Display) manufacturing processes. Bonding process includes aligning front and rear glasses with fixing clips. In this process, clips have to maintain perfect alignment between the front and rear gl

Designers have to consider voice of customer, process capability, manufacturing standards & condition, manufacturing method and characteristics of products to decide tolerances. Especially, in case of position of hole and pin, designers have to consider process capability to decide tolerances. The traditional position tolerances used in a drawing are theoretical values which are allocated to position under the worst case assembling condition that both hole and pin are the maximum material condition(MMC). However, when the process capability is high, more exact product size can be produced under stable manufacturing condition. Larger clearance of hole and pin can be allocated. In this point of view, manufacturer could increase the yield by allocating larger position tolerance than theoretical position tolerance of hole and pin considering process capability.

Designers have to consider voice of customer, process capability, manufacturing standards & condition, manufacturing method, characteristics of products to decide tolerances. Especially, in case of position of hole and pin, designers have to consider process capability to decide tolerances. The traditional position tolerances used in a drawing are theoretical values which are allocated to position under the worst case assembling condition that both hole and pin are the maximum material condition(MMC). However, When the process capability is high, more exact product size can be produced under stable manufacturing condition. larger clearance of hole and pin can be allocated. In this point of view, manufacturer could increase the yield by allocating larger position tolerance than theoretical position tolerance of hole and pin considering process capability.

Load test is performed to obtain the data to evaluate load carrying capacity and check static & dynamic characteristics of a structure by estimating the real behavior of bridge due to loading the load. The subject facility in this paper is a bridge located on the spiilway of dam and traffic is relatively less than most brige. Considering the age and operation rules of a dam, however, load test and structure programming analysis were performed to check current conditions for structure under in-depth inspection and the results of that analysis are shown.

The purpose of measuring a dam operated after design & construction is to properly operate reservoir and maintain dam structural safety by comparing the really measured data for the behavior of dam with the data for design & construction, the past mesured data and analyzing them. In this paper, the really measured data is analized for a dam facilitiy located near a seismic epicenter of earthquake that occurred on 12th, Nov. 2016 in Gyeong-ju and the results of safety inspection for a dam is shown by comparing the behavior of dam before and after occuring earthquake

The purpose of measuring a dam operated after design & construction is to properly operate reservoir and maintain dam structural safety by comparing the really measured data for the behavior of dam with the data for design & construction, the past mesured data and analyzing them. In this paper, the really measured data is analized for a dam facilitiy located near a seismic epicenter of earthquake that occurred on 12th, Nov. 2016 in Gyeong-ju and the results of safety inspection for a dam is shown by comparing the behavior of dam before and after occuring earthquake.