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Defect reconstruction of remote field eddy current belonged to electromagnetic inverse problem in materia Non-Destructive Testing. In view of disadvantages in present defect reconstruction methods, such as over-long time or excessive need for training samples, a new defect reconstruction method based on similar model and genetic algorithm was investigated as follows: similar model between non-axisymetric defect and axisymetric defect was represented, and proportionality factor was deduced by skin depth equation. As a result, the time-consuming forward problem solution in defect reconstruction, which using 3D finite element computation conventionally, was simplified to 2D finite element computation. At the same time, a method designed to accelerate convergence of genetic algorithm was adopted, and more times saving were obtained. Computation results show that, total defect reconstruction time is reduced to 7.6%, compared with directly 3D finite elemet computation, while reconstruction accuracy remains almost the same.

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Here we report molecular dynamics (MD) and free energy perturbation (FEP) simulations applied to hydroxamate-matrix metalloproteinase-2 (MMP-2) complex systems. We have developed some new force field parameters for the hydroxamate functional group that were not included in the AMBER94 force field but were necessary in our simulations. For the representation of the active zinc center, a bonded model was adopted in which restrained electrostatic potential fitting (RESP) charges were used as the electrostatic representation of this model. Using the resulted bonded model, FEP simulations predict the relative binding free energy in good agreement with the experimental value. By analyzing the molecular dynamics (MD) trajectories of the two complex systems, we can provide an explanation of why one of the two inhibitors is favored over the other. The results provide a chemical insight into the interactions between inhibitor and enzyme, and can indicate changes in the inhibitor that would enhance inhibitor-enzyme interactions.

The influence of surface polaritons on spectral energy flux at different temperatures or distances to the surface of a plate was analyzed. The relations of the net heat flux between two parallel plates with the material type were also discussed. The results demonstrate that the effect of surface polaritons is dominated in the spectral energy flux at 300 K when the distance is decreased to 100 nm. In addition, the intensity of surface polaritons increases with the temperature. The net heat flux between two parallel plates has a nearly linear relation with the temperature and is closely related to the material type. It reaches up to 2.792×107 W/m2 between two SiC plates, approximately 3~6 orders of magnitude larger than that between two different materials. However, the net heat flux between SiC and Al is merely 2329.7 W/m2, even smaller than the result calculated by the classical stefan-boltzman law between two blackbodies.