11 research outputs found
Imaging of Lamb Waves in Plates for Quantitative Determination of Anisotropy Using Photorefractive Dynamic Holography
Get PDFAnisotropic properties of sheet materials can be determined by measuring the propagation of Lamb waves in different directions. Electromagnetic acoustic transduction and laser ultrasonic methods provide noncontacting approaches that are often desired for application to industrial and processing environments. This paper describes a laser imaging approach utilizing the adaptive property of photorefractive materials to produce a real-time measurement of the antisymmetric Lamb wave mode in all directions simultaneously. Continuous excitation is employed enabling the data to be recorded and displayed by a CCD camera. Analysis of the image produces a direct quantitative determination of the phase velocity in all directions showing plate anisotropy in the plane
Reciprocal Family, Friendship and Church Support Networks of African Americans: Findings from the National Survey of American Life
No full textDiscrimination and Help-Seeking: Use of Professional Services and Informal Support Among African Americans, Black Caribbeans, and Non-Hispanic Whites with a Mental Disorder
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Post-mastectomy breast reconstruction: reducing the disparity through educational outreach to the underserved
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Profiles of Psychosocial Risk and Protective Factors and their Associations with Alcohol Use and Regular Smoking in Black Adults
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The Life Course Research Framework: Illustrative Application in the Study of Financial Behaviors
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