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왕세명;기성현;정성천
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 1998.04a
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- pp.154-159
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- 1998
In this paper, BLDC spindle motor is designed using CAE/CAT to reduce structural vibration. Motor is modeled and analyzed using a finite element analysis (FEA) program and correlated to the results of modal test. Design sensitivity analysis (DSA) of frequency is carried out and validated by the modal test of modified motor manufactured. This study shows that simulation-based design can improve quality with reduced development time.
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Kim, Dae-Kwan;Choi, Hong-Taek;Park, Gee-Yong
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2012.04a
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- pp.420-424
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- 2012
A 2-axis gimbal system is one of main disturbance sources affecting on image jitter response of a satellite. The gimbal system can be rotated on its azimuth and elevation axes, resulting in variation of its moment of inertia and structural modes, so that generates non-linear vibration characteristics. In order to estimate the jitter response, it is an indispensable process to characterize micro-vibration disturbance of the 2-axis gimbal system. In the present research, the vibration characteristics of the 2-axis gimbal system was investigated with respect to the types of stepping motors. The micro-vibration tests were performed for 2-phase and 5-phase stepping motors. The test results show that the disturbance can be reduced with vibration attenuation ratio of 60% by replacing the 2-phase stepping motor with the 5-phase one.
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Kim, Deuk-Seong;Jang, Seo-Il;Jeon, Hyeong-Jun;Lee, Yeon-Su
- Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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- 2007.11a
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- pp.1191-1196
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- 2007
This research presents a laboratory study about an annoyance of impulsive sound caused by construction site(breaker and blasting). The sources are sampled from outdoor noise and their levels range from 40 to 75 dB at the interval of 5dB. The noise unit is based on A-weighted sound exposure level (ASEL; $L_{AE}$). To make equal ASEL of outdoor noise, finite impulse response (FIR) filter is applied to the originally sampled source to include the effect of distance attenuation. The evaluation method of jury test adopted a Semantic Difference Method (SDM). In the result of the Jury test for impulsive noise, the annoyance response of blasting noise was higher than that of breaker noise.
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