• Journal of the Korean Society for Precision Engineering
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• v.25 no.12
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• pp.100-106
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• 2008

In this paper, the injection molding process of automotive seat-back cover is analyzed in terms of simulation and of experiment. FE analysis was used to obtain molding conditions such as injection pressure, filling pattern, packing, shrinkage. Vacuum system for low pressure injection molding is developed in the experiment. Low pressure injection molded parts have been compared with conventional molded parts in terms of molding quality and mechanical properties. Based on the results, good product and the productivity improvement can be obtained in low pressure injection molding for automotive seat-back cover.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.2
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• pp.146-153
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• 2014

This study investigates the effects of seat-design elements such as seating arrangement, shape, and height on speech privacy in high-speed trains. For the evaluation of speech privacy, acoustic simulation software was used to reproduce room acoustical conditions in passenger cars on the basis of in-situ measurement data. The influences of speech source directivity and source height on privacy distance ($r_P$) were investigated, and it was found that $r_P$ determined using an omni-directional source was relatively shorter than that determined using a directional source. It was also found that $r_P$ decreased when the source height was lower than the height of the seat-back because the seat-back blocked the propagation of speech from the sound source. The effect of seating arrangement was not significant when comparing the vis-a-vis seating and one-side seating arrangements. In addition, among the alternative seat-designs, the seats that block the space between the seats and cover the space near the ear were found to show significantly enhanced speech privacy in high-speed train passenger cars.