| Popis: |
A new deflection tomography system was put forward and named Auto-adapted Iterative Deflection Tomography (AIDT). It was tested to approach accurate reconstruction of a high frequency field containing shock waves with sufficient projections. A high frequency field was constructed with Gauss and rectangle window functions. It was simulated to project in all directions with angle resolving rate per degree. Two cross projections was selected to simulate reconstructing the model field by AIDT. Then, the number of projections was increased step by step in order to approach the accurate values of the model. All reconstructed results were studied. As a result, all high frequency sections are distorted much. With a few projections, such as two projections, the reconstructed results lost the basic characteristics of the model. With projections increasing, the distortions get lighter and lighter. Near the critical projections, such as twenty-four projections, the reconstructed field becomes similar to the model except some high frequency sections. When eighty-four projections are employed, the reconstructed result is in accord with the model. In this case, the Mean Square Error(MSE) is 0.00003609. But up to one hundred and eighty projections, the reconstructed result almost stopped improving. In this case, the MSE is 0.00003231. As we know, these are most accurate reconstructions to now. AIDT can accurately reconstruct high frequency fields with shock waves. |
