X

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Comparative Studies. Non-European Languages/Literatures  (4)
  • 1
    Online Resource
    Online Resource
    Vibration spectroscopy and guided wave propagation data as indicators of structural and mechanical degradation of human bones
    Acoustical Society of America (ASA) ; 2008
    In:  The Journal of the Acoustical Society of America Vol. 123, No. 5_Supplement ( 2008-05-01), p. 3786-3786
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 123, No. 5_Supplement ( 2008-05-01), p. 3786-3786
    Abstract: Vibration spectroscopy and guided wave modes analysis of long bones are investigated as tools to assess bone quality or integrity. Two different methods of vibroacoustic experiments are undertaken to determine the health of dry human tibia bones. The first method involves vibratory modes of the bone, excited and measured by piezoelectric transducers and sensors respectively. The measured frequency response is validated using finite element simulation (FES), also used in the inverse problem for retrieval of the bone material properties. The principle of in-plane (IP) and out-of-plane (OP) mode splitting to determine the degree of the damage, that we developed in an earlier study, is applied to classify the bones according to their degree of damage. The second method involves the analysis of the guided wave phase velocities recovered using the reassigned Gabor spectrogram from signals measured along the diaphysis of the tibias. The frequency difference between the peaks of the split modes are then correlated to the phase velocities of the retrieved Lamb modes.
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.2935441
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2008
    detail.hit.zdb_id: 1461063-2
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 2
    Online Resource
    Online Resource
    Investigations in ultrasonic tomography
    Acoustical Society of America (ASA) ; 1999
    In:  The Journal of the Acoustical Society of America Vol. 105, No. 2_Supplement ( 1999-02-01), p. 1015-1015
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 105, No. 2_Supplement ( 1999-02-01), p. 1015-1015
    Abstract: Ultrasonic tomography (UT) is a technique to reconstruct the spatial distribution of some physical parameter of an object from measurements of the scattered field. The measurements are made for more or less dense sets of emitter and receiver positions and of frequencies of the interrogating wave. This inverse scattering problem was solved by using a Born approximation that leads to a particularly simple and attractive linear relation between the object function (OF) and the scattered field, particularly in the far-field (2-D or 3-D Fourier transform), making it possible, in principle, to reconstruct the OF in near real time for a sufficiently large set of scattering data. Ultrasonic tomography was investigated numerically and experimentally. Numerical simulations, using ideal measures with ideal objects, allow the examination in detail of the influence of various parameters such as the object’s dimension and contrast, transducers bandwidth, etc. It allows one to analyze what happens when the Born approximation is no longer valid (high frequencies, high contrasts), to find limits of quantitative and qualitative imagery, and to imagine various improvement procedures (e.g., superresolution procedures leading to high resolution with low frequencies). Experimentations (with a mechanical and an antenna-based system) show the applicability of the method for medical and materials applications.
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.424864
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 1999
    detail.hit.zdb_id: 1461063-2
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 3
    Online Resource
    Online Resource
    Acoustic response of a soniclike crystal within a rigid frame porous plate
    Acoustical Society of America (ASA) ; 2008
    In:  The Journal of the Acoustical Society of America Vol. 123, No. 5_Supplement ( 2008-05-01), p. 3039-3039
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 123, No. 5_Supplement ( 2008-05-01), p. 3039-3039
    Abstract: The acoustic response (in particular, the transmission) of a periodic distribution of macroscopic inclusions within a rigid frame, porous plate (similar to a sonic crystal) is studied by the multipole method. Numerical results show that the addition of grating stacks leads to band gaps within the audible frequency range for a small number of stacks, this being associated with a large decrease of the transmission coefficient of the initial plate. The first band gap is of practical interest for noise suppression. The second band gap enables total acoustic absorption within a narrow frequency range due to the fact that a modified mode of the plate lies within this band gap.
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.2932713
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2008
    detail.hit.zdb_id: 1461063-2
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
  • 4
    Online Resource
    Online Resource
    Recovery of structural degradation indicators of human bones using elastic waves.
    Acoustical Society of America (ASA) ; 2010
    In:  The Journal of the Acoustical Society of America Vol. 127, No. 3_Supplement ( 2010-03-01), p. 2032-2032
    Details
    In: The Journal of the Acoustical Society of America, Acoustical Society of America (ASA), Vol. 127, No. 3_Supplement ( 2010-03-01), p. 2032-2032
    Abstract: Non-ionizing techniques of bone characterization have mostly been based on ultrasonic wave propagation. In this study, bone is characterized via its linear response to vibratory solicitations. The analysis of the response of bones to transient mechanical excitation is made both theoretically and experimentally. An orthotropic three-dimensional finite element interaction model (FEIM) using computerized tomography scan image geometries of excised dry human tibiae bones is developed. The model parameters (nine elastic constants) are recovered by solving an inverse eigenvalue problem using resonance frequencies from vibration spectroscopy. Transient waves are excited and signals acquired along the diaphysis of the tibiae, experimentally by employing piezoelectric transducers and numerically using FEIM and a time integration scheme. The elastic waves propagating as guided modes in the bone are investigated using reassigned bilinear time-frequency distribution. To avoid ambiguity in determining the elastic wave phase velocities due to the dispersive nature of propagation in bone, the longitudinal L(0,1) and flexural F(1,1) phase velocities, measured at their asymptotes, i.e., the bar and Rayleigh velocities respectively, are proposed as indicators for assessing the strength of long bones. Their sensitivity to changes in bone state like the effect of cortical thickness variation due to aging and osteoporosis is examined.
    Type of Medium: Online Resource
    ISSN: 0001-4966 , 1520-8524
    URL: Article
    DOI: 10.1121/1.3385337
    RVK:
    EQ 1000
    Language: English
    Publisher: Acoustical Society of America (ASA)
    Publication Date: 2010
    detail.hit.zdb_id: 1461063-2
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Online Resource
    Open Access Request
    Availability (electronic / print)
Nothing or not found what you are looking for? Please check your search query or use the Interlibrary Loan Search.
Close ⊗
This website uses cookies and the analysis tool Matomo. Further information can be found on the KOBV privacy pages