• Journal of the Korean Society for Precision Engineering
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• v.30 no.8
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• pp.790-796
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• 2013

Micro-speaker diaphragms play an important role in generating a desired audio response. The diaphragm is generally a circular membrane, and the cross section is a double dome, with an inner dome and an outer dome. To improve the sound quality of the speaker, a number of corrugations may be included in the outer dome region. In this study, the role of these corrugations is investigated using two kinds of finite element method (FEM) calculations. Structural FEM modeling was carried out to investigate the change in stiffness of the diaphragm when the corrugations were included. Modal FEM modeling was then carried out to compare the natural frequencies and the resulting vibrational modes of the plain and corrugated diaphragms. The effects of the corrugations on the vibration characteristics of the diaphragm are discussed.

• Journal of the Semiconductor & Display Technology
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• v.14 no.2
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• pp.1-7
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• 2015

In this paper, a new capacitive pressure sensor has been proposed for a displacement measurement. The new sensor is mainly composed of a gap of $5{\mu}m$ and a notch of $1{\mu}m$. And the sensor has the performance as the high sensitivity and capacitance compared with a commercial capacitive sensor. Therefore, the advantages of the new capacitive pressure sensor are good sensitivity in normal range, mechanically robust and large overload protection. The analytical model is induced for confirming the performance of the proposed sensor. In addition, FEM (finite elements method) simulation has been performed to verify the analytical model. Firstly, the displacement characteristics of diaphragm membrane were simulated by the analytical model and FEM in the case of different structure and materials. At last, through this analysis, these simulation results can be predicted the change of the performance when the device parameters are varied. And it is used as a design tool to achieve at a set of performance we desired.

• Journal of Korean Association for Spatial Structures
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• v.7 no.2 s.24
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• pp.115-124
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• 2007

The initial shape is arrived at by a self-formation process, which accomplishes a form in the natural world, or is determined analytically by considering the equilibrium of initial stress only. Therefore, the self-formation process, which accomplishes a form in the natural world is grasped and the types of modeling techniques available to find the shapes of soft structures are well investigated and classified. To establish a form-finding modeling techniques, the models of string, soap film, fabric, rubber, plaster, and etc. are used. These modeling techniques can be used as a method of understanding the characteristics of structures when the material of model shows similar characteristics. Generally, the model test confirms the structure based on numerical analysis, at the same time it is important preceding process to develop such a program. With the above process, the relationship between model test and numerical analysis becomes a feedback process. Therefore, in this study, two examples which have been accomplished from such a technique are investigated and considered according to modeling process.