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Based on their three-dimensional mode shapes, the vibrational modes of free finite length thick cylinders can be classified into 6 categories, consisting of pure radial, radial motion with radial shearing, extensional, circumferential, axial bending, and global modes. This classification, together with the numbers of both the circumferential and the longitudinal nodes, is sufficient to identify each mode of a finite length thick cylinder. The mode classification was verified experimentally by measurements on a thick cylinder. According to the displacement distribution ratio in the radial, tangential and longitudinal directions, the effect of varying cylinder length on the vibrational modes is such that all the modes can be broadly categorized as either pure radial modes, or non pure radial modes. The natural frequencies and mode shapes of the former are dependent upon only the radial dimensions of the models, while the natural frequencies and mode shapes of the latter are dependent upon both the axial length and radial thickness.

In this paper, a novel G-shaped defected microstrip structure (DMS) is presented. Compared with the conventional DMS, the proposed G-shaped DMS exhibits lower resonant frequency and wider stopband. A lowpass filter with 3 dB cutoff frequency at 3.17 GHz using four pairs of parallel cascaded G-shaped DMS units is designed and fabricated. The measured results show that the transition band is only 0.09 GHz and the stopband over 25 dB attenuation covers 3.4 GHz to 10 GHz. The measured and simulated results are in good agreement.

/npsi/ctrl?lang=en http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/ctrl?lang=fr Access and use of this website and the material on it are subject to the Terms and Conditions set forth at http://nparc.cisti-icist.nrc-cnrc.gc.ca/npsi/jsp/nparc_cp.jsp?lang=en NRC Publications Archive Archives des publications du CNRCThis publication could be one of several versions: author's original, accepted manuscript or the publisher's version. / La version de cette publication peut être l'une des suivantes : la version prépublication de l'auteur, la version acceptée du manuscrit ou la version de l'éditeur. Control Engineering Journal, 44, 2, pp. 79-91, 1996-04-01 Digital frequency-weighting filters for evaluation of human exposure to building vibration Hunaidi, O.; Guan, W. Noisehttp://www.nrc-cnrc.gc.ca/irc Digit a l fre que nc y-w e ight ing filt e rs for e va lua t ion of hum a n e x posure t o building vibra t ion NRCC-38968Hunaidi, O.; Guan, W. April 1996A version of this document is published in / Une version de ce document se trouve dans:Noise Control Engineering Journal, 44, (2), pp. 79-91, April 01, 1996The material in this document is covered by the provisions of the Copyright Act, by Canadian laws, policies, regulations and international agreements. Such provisions serve to identify the information source and, in specific instances, to prohibit reproduction of materials without written permission. For more information visit http://laws.justice.gc.ca/en/showtdm/cs/C-42Les renseignements dans ce document sont protégés par la Loi sur le droit d'auteur, par les lois, les politiques et les règlements du Canada et des accords internationaux. Ces dispositions permettent d'identifier la source de l'information et, dans certains cas, d'interdire la copie de documents sans permission écrite. Pour obtenir de plus amples renseignements : http://lois.justice.gc.ca/fr/showtdm/cs/C-42 Digital frequency-weighting filters for evaluation of human exposure to building vibration M. Osama AI-Hunaidi and Wei Guan s ) (Received 1995 March 09; revised 1995 December 26; accepted 1996 January 18) According to some International and National Standards, frequency weighting is the preferred method for evaluation of buman exposure to broadband vibration in buildings. The weighting functions are defined b)' prot,Qtype filters that may be implemented in analog or digital form. For this paper, frequency-weighting functions specified by the ISO 8041 and BS 6841 Standards were simulated in software as time-domain digital IDters. Simulation procedures, software implementation, and verification of tolerance requirements are presented. The digital filters implemented here conformed closely to specifications in the Standards. A FORTRAN subroutine is provided for calculating the coefficients of the digital filters.

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