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In order to improve the accuracy of gridless method, the third-order WENO reconstruction is introduced as the substitution of traditional linear reconstruction. The stencil required for implementing WENO reconstruction in the gridless cloud is obtained by setting a local coordinate in the direction of each satellite point and introducing a virtual point. Based on the obtained stencil, the WENO reconstruction is then carried out for approximating the flow variables at the midpoint between the central and satellite points of the gridless cloud. An interpolation technique is also proposed to determine the flow variables of the virtual point, in which the existed information of the cloud is adequately utilized. The resulting WENO reconstruction method, compiling with Roe's Riemann solver for obtaining numerical flux and third-order TVD Runge-Kutta scheme for time advancing, is applied to solve Euler equations. Typical 2D cases are first simulated, and the numerical results obtained present the desired third order of accuracy. The shock tube problem and supersonic semi-cylinder flow are then simulated, and a higher resolution of shock and contact discontinuity is observed. The paper ends with numerical example of the flow field of shock wave through curved channel around double cylinders, which demonstrates the ability of the present method for treating more complicated flows involving unsteady shocks. [ABSTRACT FROM AUTHOR]

Data on reproductive traits of 670 litters of different Am genotypes Wannanhua sow under different climatic conditions were analyzed by the least square model in order to investigate the effects of the climate factors and the Am genotypes on sow's reproductivity. The results showed that the reproductive performance of sow depended on the monthly change of climate regularly. High temperature from July to September had worse effect on sow's reproductivity, especially (P < 0.05). A certain variation existed among reproductive performances of Wannanhua sows at Am loci. AmAB's was better, followed by AmAA, then AmBB and AmBC were poor. But the variance was in significant (P > 0.05). Furthermore, there was strong interactive effect between Am genotypes and the breeding season. In addition, the litter size, the number of live born and the number of weaning pig had a negative correlation with the mean air temperature and photoperiod significantly (P < 0.05 or P < 0.01).