Open Access

ARTICLE

Claude Prost^{1, *}, Bruno Abdelnour²
Sound & Vibration, Vol.52, No.5, pp. 2-5, 2018, DOI:10.32604/sv.2018.00002
Abstract Tall and slender substation equipment is prone to failure under seismic excitations. The consequences of such failure can be devastating and lead to weeks or months of lost power.
The IEEE Std 693-2005 ensures that all substation equipment installed in high seismic areas are designed to withstand earthquakes of a severity related to that area.
There are numerous ways to increase the seismic strength of substation equipment and this paper will discuss doing so by base isolation, specifically using wire rope isolators (WRIs).
It is the purpose of this paper to present a case study in which the Socitec Group… More >

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1286

Open Access

ARTICLE

Pei Yu, Yong Shen^*, Ziyun Liu
Sound & Vibration, Vol.52, No.5, pp. 6-11, 2018, DOI:10.32604/sv.2018.04090
Abstract A lot of work has focused on compensating nonlinear distortions of the microspeaker under large excitation, yet it is unclear at which level the effect of nonlinear distortion is imperceptible or not annoying. In this study virtual listening tests were performed to evaluate the deterioration of sound quality in music signals with different levels of nonlinear distortion by a microspeaker. Binaural recordings of the music played by the microspeaker were made at different voltage levels, adjusted to the same RMS power, and afterwards reproduced by a low distortion reference headphone. The “double-blind triple-stimulus with hidden reference” method was used in… More >

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2235

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ARTICLE

Ameya M. Mahadeshwar^{1, *}, Sangram S. Patil¹, Vishwadeep C. Handikherkar¹, Vikas M. Phalle¹
Sound & Vibration, Vol.52, No.5, pp. 12-21, 2018, DOI:10.32604/sv.2018.03927
Abstract Wide range of rotating machinery contains an inherent amount of unbalance which leads to increase in the vibration level and related faults. In this work, the effect of different operating conditions viz. the unbalanced weight, radius, speed and position of the rotor disc on the unbalance in rotating machine are studied experimentally and analyzed by using Response Surface Methodology (RSM). RSM is a technique which consists of mathematical and statistical methods to develop the relationship between the inputs and outputs of a system by distinct functions. L27 Orthogonal Array (OA) was developed by using Design of Experiments (DOE) according to… More >

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1299

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Ling Zhang^{1, 2}, Xiaoyan Lei¹, Jian Jiang², Qingsong Feng¹
Sound & Vibration, Vol.52, No.5, pp. 22-27, 2018, DOI:10.32604/sv.2018.04058
Abstract Underground railway vibration source strength is one of the key values used for environmental impact assessment and the evaluation of mitigation measure’s performance. However, currently there is no international standard of measuring the underground railway vibration source strength for such purposes. The available local standards and industrial guidelines do not agree on measurement locations as well as the metrics for presenting the source strength. This has caused many confusions. This paper aims to study the suitable measurement location and metrics using the data from a large scale field-testing carried out at the Nanchang underground railway (Metro Line 1, China) in… More >

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1204

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ARTICLE

Zhiliang Zhang, Yong Shen^*, Jie Xia, Yuchen Shen
Sound & Vibration, Vol.52, No.5, pp. 28-33, 2018, DOI:10.32604/sv.2018.03862
Abstract Since microspeakers are widely used in mobile phones, high power is usually applied to obtain sufficient output sound pressure. However, the electric power is almost converted into heat, leading to the thermal problem in microspeakers. Compared with large loudspeaker, microspeakers are smaller and the under yoke is relatively closed, causing the heat transfer more complex. In this study, a three-stage nonlinear thermal model was proposed for analyzing the thermal behavior in microspeakers. The inside air is a buffer area between the voice coil and magnet, and modeled as a middle stage of the heat transfer. The forced convection is still… More >

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