薄体位势边界条件识别反问题正则化边界元方法

针对二维薄体位势柯西边界条件识别反问题，提出了解析积分和奇异值分解联合正则化算法．解析积分用于薄体位势问题边界元法中几乎奇异积分的正则化．奇异值分解技术用来求解系统方程．数值算例研究了狭长比为1E-8和1E-7的薄体问题，计算结果表明该算法的有效性和精确性．

Inverse identification of boundary conditions for potential problems of thin body using BEM

The optimum interference assembly and the elastic-plastic analysis of thick-walled combination cylinders subjected to internal pressure with the unified strengths criterion for materials with different strengths in tension and compression were studied. The contact pressure, optimum contact pressure, magnitude of optimum interference fit tolerance and elastic-plastic limits of thick-walled combination cylinders in conjunction with the unified strength criterion were derived. Unlike classical elastic-plastic solutions, the present solutions took into consideration the different strengths in tension and compression, and the intermediate principal stress effects, involving the two parameters of the unified strength criterion. The solutions of the thick-walled combination cylinders subjected to internal pressure with the Coulomb-Mohr yield criterion for materials with different strengths in tension and compression were also obtained. Comparisons between results with respect to Coulomb-Mohr yield criterion and the unified strength criterion, the effects of the strength-difference and the intermediate principal stress on the optimum contact pressure, the magnitude of optimum interference fit tolerance and the elastic-plastic limits were presented.