Randall Summers

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—In this study we provided an experimental test bed for validating features of the Arbitrary Lagrangian Eulerian Grid for Research Applications (ALEGRA) code over a broad range of strain rates with overlapping diagnostics that encompass the multiple responses. A unique feature of the ALEGRA code is that it allows simultaneous computational treatment, within(More)
A method is described for automatically tracking spatial modulation of magnetization tag lines on gated cardiac images. The method differs from previously reported methods in that it uses Fourier based spatial frequency and phase information to separately track horizontal and vertical tag lines. Use of global information from the frequency spectrum of an(More)
Neointimal hyperplasia after angioplasty was followed in vivo in rats by using MR microscopy and surgically implanted RF imaging coils. By using an inductively coupled pick-up coil, the arteries were imaged 4 days before and 3, 7, and 14 days after angioplasty with a 3DFT spin echo sequence. Eight of 10 angioplastied rats showed moderate to severe stensois(More)
—ALEGRA is a multi-material, arbitrary-Lagrangian-Eulerian (ALE) code for solid dynamics being developed by the Computational Physics Research and Development Department at Sandia National Laboratories. It combines the features of modern Eulerian shock codes, such as CTH, with modern Lagrangian structural analysis codes. With the ALE algorithm , the mesh(More)
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