Browsing by Author "BAI, MR"

Now showing 1 - 7 of 7

ACOUSTICAL SOURCE CHARACTERIZATION BY USING RECURSIVE WIENER FILTERING
(1995-05-01)
BAI, MR
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交大名義發表
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機械工程學系
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National Chiao Tung University
;
Department of Mechanical Engineering
ACTIVE NOISE CANCELLATION BY USING THE LINEAR-QUADRATIC GAUSSIAN INDEPENDENT MODAL SPACE CONTROL
(1995-05-01)
BAI, MR
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SHIEH, CF
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交大名義發表
;
機械工程學系
;
National Chiao Tung University
APPLICATION OF BEM (BOUNDARY ELEMENT METHOD)-BASED ACOUSTIC HOLOGRAPHY TO RADIATION ANALYSIS OF SOUND SOURCES WITH ARBITRARILY SHAPED GEOMETRIES
(1992-07-01)
BAI, MR
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
;
Department of Mechanical Engineering
A method employing holograms that conform with arbitrarily shaped sources has been developed for enhancing conventional near-field acoustic holography, which has been limited to sources with simple geometries, e.g., planar or cylindrical surfaces. Four holography transformation algorithms have been developed, based on acoustic holography theory and the boundary element method (BEM). Singular value decomposition (SVD) has been incorporated into the algorithms in order to alleviate the ill-posed nature frequently encountered in backward reconstruction of a field. A pulsating sphere, a cylinder with spherical endcaps, and a vibrating piston set in a rigid sphere have been adopted in a numerical simulation for verifying the algorithms. Satisfactory agreement has been achieved between the holographically transformed results and the analytical solutions.
CONTROL BASED ACTIVE NOISE CANCELERS FOR DUCTS
(1992)
BAI, MR
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機械工程學系
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Department of Mechanical Engineering
EXPERIMENTAL CHARACTERIZATION OF THE VIBRATIONAL BEHAVIOR OF A FLUID-FILLED THIN SHELL FOR THE PURPOSE OF RESPONSE ESTIMATION
(1995-11-01)
BAI, MR
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LIN, YY
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機械工程學系
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Department of Mechanical Engineering
Experimental techniques are proposed for developing a model to estimate structural vibrations induced by internal acoustic pressure at low frequencies. In these methods, the acoustic field and the structure are treated as a coupled system with the acoustic loading effect taken into account. The response model between the internal pressure and the surface vibration is established by a modified modal test on the coupled system. Experiments are performed to investigate the surface vibrations of a closed steel cylindrical shell excited by a loudspeaker inside. The experimental results show that developed techniques provide accurate estimation for the acoustically induced vibrations. (C) 1995 Acoustical Society of America.
EXPERIMENTAL CHARACTERIZATION OF THE VIBRATIONAL BEHAVIOR OF A FLUID-FILLED THIN SHELL FOR THE PURPOSE OF RESPONSE ESTIMATION
(1995-11-01)
BAI, MR
;
LIN, YY
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
Experimental techniques are proposed for developing a model to estimate structural vibrations induced by internal acoustic pressure at low frequencies. In these methods, the acoustic field and the structure are treated as a coupled system with the acoustic loading effect taken into account. The response model between the internal pressure and the surface vibration is established by a modified modal test on the coupled system. Experiments are performed to investigate the surface vibrations of a closed steel cylindrical shell excited by a loudspeaker inside. The experimental results show that developed techniques provide accurate estimation for the acoustically induced vibrations. (C) 1995 Acoustical Society of America.
STUDY OF ACOUSTIC-RESONANCE IN ENCLOSURES USING EIGENANALYSIS BASED ON BOUNDARY ELEMENT METHODS
(1992-05-01)
BAI, MR
;
交大名義發表
;
機械工程學系
;
National Chiao Tung University
;
Department of Mechanical Engineering
It is well known that, from the modal theory of room acoustics, resonance will occur if the driving frequency of a sound source located in a room coincides with one of the natural frequencies of the sound field. In this study, an eigenanalysis technique based on the boundary element method (BEM) is developed for extracting eigenmodes of a sound field in an enclosure. A method of singular value search, in conjunction with a golden section optimization algorithm, is utilized for efficient calculation of eigenmodes. In particular, modes associated with repeated eigenvalues can be well resolved by the technique developed in this research. Enclosures of various geometries have been analyzed by using the developed algorithm in a numerical simulation. Satisfactory agreement has been achieved between the BEM results, the FEM results, and the analytical solutions if available.