Magnetic resonance elastography (MRE) is an elastic tissue property imaging modality in which the phase-contrast based MRI imaging technique is used to measure internal displacement induced by a harmonically oscillating mechanical vibration. MRE has made rapid technological progress in the past decade and has now reached the stage of clinical use. Most of the research outcomes are based on the assumption of isotropy. Since soft tissues like skeletal muscles show anisotropic behavior, the MRE technique should be extended to anisotropic elastic property imaging. This paper considers reconstruction in a transversely isotropic model, which is the simplest case of anisotropy, and develops a new non-iterative reconstruction method for visualizing the elastic moduli distribution. This new method is based on an explicit representation formula using the Newtonian potential of measured displacement. Hence, the proposed method does not require iterations since it directly recovers the anisotropic elastic moduli. We perform numerical simulations in order to demonstrate the feasibility of the proposed method in recovering a twodimensional anisotropic tensor.

Abstract. This study is aimed at investigating the anisotropy of shape memory effect in Fe-based alloy. An Fe-15Mn-3Si-4Co-5Cr alloy is cold rolled by 92%, and annealed at 630 "C for 45min. The alloy undergoes y-»e -*a ' transformation by cold rolling and y is restored with a major preferred orientation of (110) y [001] y by the annealing. The specimens for shape memory effect and tensile test are taken 0, 45, 70, 80 and 90 degs to the rolling direction. The specimen taken along 70 degs to the rolling direction exhibits the best shape memory effect. An analysis of the (110)y [001]y texture reveals that the specimen experiences the deformation stress along [221]y which is the most expandable direction in the y->e transformation. In tensile test, the best SME specimen shows the lowest yield stress, indicating that the transformation take place most easily since the deformation is applied to the preferential direction to the transformation. key words; shape memory effect, texture, Fe-based alloy, martensitic transformation