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Full-Text Articles in Engineering
Inverse Scattering Image Quality With Noisy Forward Data, Thomas J. Sorensen
Inverse Scattering Image Quality With Noisy Forward Data, Thomas J. Sorensen
Theses and Dissertations
Image quality metrics for several inverse scattering methods and algorithms are presented. Analytical estimates and numerical simulations provide a basis for poor image quality diagnostics. The limitations and noise behavior of reconstructed images are explored analytically and empirically using a contrast ratio. Theoretical contrast ratio estimates using the canonical PEC circular cylinder are derived. Empirical studies are conducted to confirm theoretical estimates and to provide examples of image quality vs SNR for more complex scatterer profiles. Regularized sampling is shown to be more noise sensitive than tomographic reconstructive methods.
Development Of An Ultrasonic Nde&T Tool For Yield Detection In Steel Structures, Yilmaz Bingol
Development Of An Ultrasonic Nde&T Tool For Yield Detection In Steel Structures, Yilmaz Bingol
LSU Doctoral Dissertations
Nondestructive Evaluation and Testing (NDE&T) is a commonly used and rapidly growing field that offers successful solutions for health assessment of structures. NDE&T methods have gained increasing attention in the last few decades especially with the contribution of the advancements in computer and instrumentation technologies. The applications of numerous NDE&T methods in civil engineering mostly focus on material characterization and defect detection. Techniques for nondestructively identifying the stress state in materials, on the other hand, mostly rely on the Theory of Acoustoelasticity. However, the sensitivity and the accuracy of acoustoelasticity are affected by several factors such as the microstructure of …