全部 标题 作者
关键词 摘要

OALib Journal期刊
ISSN: 2333-9721
费用:99美元

查看量下载量

相关文章

更多...
工程力学  2013 

基于小波变换的非平稳脉动风时变功率谱估计方法研究

DOI: 10.6052/j.issn.1000-4750.2011.10.0656, PP. 89-97

Keywords: 健康监测,小波变换,非平稳随机过程,脉动风,时变功率谱

Full-Text   Cite this paper   Add to My Lib

Abstract:

为揭示非平稳随机脉动风的时频特性,基于小波变换原理推导了时变功率谱的时间、频率和幅值与小波变换系数的关系,建立了非平稳随机脉动风时变功率谱估计的小波函数加权和法,并采用模拟非平稳脉动风和实测台风过程对理论推导结果进行了验证。研究结果表明:非平稳随机过程在某一时刻的不同尺度小波变换系数是一个以此非平稳随机过程的调制函数与小波函数的乘积为调制函数的非平稳随机过程的傅里叶变换,非平稳随机过程的时变功率谱等于不同尺度和不同时移的小波函数模平方的加权和,小波函数加权和法计算的非平稳随机脉动风的时变功率谱与理论结果具有良好的一致性。小波函数加权和法可有效地估计非平稳随机脉动风的时变功率谱,估计的时变功率谱可为进一步理解强(台)风的随机脉动特性奠定基础。

References

[1]  Tian Yunsheng. Analysis of evolutionary power spectra density function of ground motion induced by blasting seismic [J]. Explosion and Shock Waves, 2007, 27(1): 7―12. (in Chinese)
[2]  Timoshenko S, Yang D H, Weaver W. 工程中的振动问题[M]. 胡人礼, 译. 北京: 人民铁道出版社, 1978: 293―295.
[3]  Priestley M B. Power spectral analysis of nonstationary random processes [J]. Journal of Sound and Vibration, 1967, 6: 86―97.
[4]  张亚辉, 林家浩. 多点非均匀调制演变随机激励下结构地震响应[J]. 力学学报, 2001, 33(1): 87―95.
[5]  Timoshenko S, Yang D H, Weaver W. Vibration problems in engineering [M]. Translated by Hu Renli. Beijing: People’s Railway Press, 1978: 293―295. (in Chinese)
[6]  克拉夫 R W, 彭津 J. 结构动力学[M]. 王光远, 译. 北京: 科学出版社, 1981: 210―211.
[7]  Clave R W, Penzien J. Structural dynamics [M]. Translated by Wang Guangyuan. Beijing: Science Press, 1981: 210―211. (in Chinese)
[8]  Bokaian A. Natural frequencies of beams under compressive axial loads [J]. Journal of Sound and Vibration, 1988, 126(3): 237―246.
[9]  Abramovich H. Natural frequencies of Timoshenko beams under compressive axial loads [J]. Journal of Sound and Vibration, 1992, 157(5): 183―189.
[10]  Kosmatka J B. An improved two-node finite element for stability and natural frequencies of axial-loaded Timoshenko beams [J]. Computer & Structures, 1995, 57(6): 141―149.
[11]  Zhang Yahui, Lin Jiahao. Seismic responses of structures subjected to non-stationary modulated differential evolutionary random excitations [J]. ACTA Mechanica Sinica, 2001, 33(1): 87―95. (in Chinese)
[12]  樊剑, 刘铁, 胡亮. 基于现代时频分析技术的地震波时变谱估计[J]. 振动与冲击, 2007, 26(11): 79―84.
[13]  Mei C, Karpenko Y, Moody S, Allen D. Analytical approach to free and forced vibrations of axially loaded cracked Timoshenko beam [J]. Journal of Sound and Vibration, 2006, 291(4): 1041―1060.
[14]  Fan Jian, Lin Tie, Hu Liang. Time-varying spectrum estimation of earthquake ground motion via modern time-frequency analysis [J]. Journal of Vibration and Shock, 2007, 26(11): 79―84. (in Chinese)
[15]  Li Q S. Vibratory Characteristics of Timoshenko beams with arbitrary number of cracks [J]. Journal of Engineering Mechanics, 2003, 129(11): 1355―1359.
[16]  Shinozuka M, Jan C M. Digital simulation of random processes and its applications [J]. Sound and Vibration, 1972, 25(1): 111―128.
[17]  Aydin Kamil. Vibratory characteristics of axially-loaded Timoshenko beams with arbitrary number of cracks [J]. Journal of Vibration and Acoustics, 2007, 129(6): 341―354.
[18]  Shinozuka M, Yun C B. Stochastic methods in wind engineering [J]. Journal of Wind Engineering and Industrial Aerodynamics, 1990, 36: 829―843.

Full-Text

Contact Us

service@oalib.com

QQ:3279437679

WhatsApp +8615387084133