Conversion criterion and time step control are corrected for smoothed particle hydrodynamics-finite element method (SPH-FEM) conversion algorithm. Impact of a 7.62 mm rifle bullet against a special heat treated 30CrMnSiA steel target plate is simulated in full-size in 3D using the corrected SPH-FEM conversion algorithm, in which distorted finite elements of the bullet are converted into SPH particles. An elastic-plasticity model is used for bullet, and corrected Johnson-Cook and Gruneisen EOS are used for target. Two destroyed modes of disc-shape plastic deformation and plugging perforation are calculated for different initial velocities of bullet. Good agreement between numerical results and experimental observations shows that the corrected SPH-FEM conversion algorithm could use finite elements and SPH particles efficiently, which provides an effective tool for simulation of a soft core bullet impacting on a hard plate.

A weighting approach for ray matrix in ART algorithm for ultrasonic computerized tomogrnphy of concrete is developed. Firstly。a low-resolution image is generated by BPT algorithm and which is used asinitial value of iteration.Then,information of lowresolution image is used as weighting coefficients for ray matrix of ART algorithm.Image information and numerical information are used fully.High speed and low speed abnormal units can be weighted.As data error is less than 0.5%.examples show that the accuracy and iteration speed of improved method are better than that of traditional ART algorithm.