In this paper, the theory of optical synthetic aperture imaging system is described, with emphasis on the image evaluation by the Point Spread Function (PSF) and Optical Transfer Function (OTF). The optical synthetic aperture imaging technique achieves higher resolution at the cost of decreasing of Modulation Transfer Function (MTF) in near mid-band regions, and of increasing the sidelobes of the PSF. The image evaluation methods for optical synthetic aperture imaging system are given, such as two-point resolution criterion and MTF. The disadvantage of evaluation methods is analyzed by Rayleigh criterion, Sparrow criterion and threshold criterion. The conclusion is that the imaging quality of synthetic aperture system is no better than that of the single sub-aperture system when the sidelobe is 0.5 times of the central lobe of the PSF. Finally，we propose new evaluation criterions, such as the efficiency factor and quality factor, which are directly linked to MTF.

In a transient analysis of an edge dislocation accelerating through the shear wave speed barrier, stress on the forming Mach fronts is analyzed, the wave front equations are given, as well as the effect of the acceleration of the moving edge dislocation on the geometry of the fronts.

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The paper makes a deep analysis of the adverse selection formation mechanism under the condition of information asymmetry through the establishment of adverse selection game model in construction market. The paper seeks the root of the construction market risk based on the perspective of information economics. Due to asymmetric information, the adverse selection makes the low strength level engineering quality responsible units expel the high strength level engineering quality responsible units form the construction market , and greatly increases the risk of the construction market, which will make it difficult for construction engineering quality to be guaranteed, and lead to engineering project quality risk. The paper puts forward some effective countermeasures and suggestions to avoid construction market quality risk from both sides of the construction information symmetry angle.

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