Riemann problem for the zero-pressure flow in gas dynamics

The Riemann problem for zero-pressure flow in gas dynamics in one dimension and two dimensions is investigated. Through studying the generalized Rankine-Hugoniot conditions of delta-shock waves, the one-dimensional Riemann solution is proposed which exhibits four different structures when the initial density involves Dirac measure. For the two-dimensional case, the Riemann solution with two pieces of initial constant states separated at a smooth curve is obtained.     

Cauchy型奇异积分的近似求积和带Cauchy核的奇异积分方程的数值解

Ｃａｕｃｈｙ型奇异积分的近似求积和带Ｃａｕｃｈｙ核的奇异积分方程的数值解李杰权（北京师范大学北京市１００８７５）本文主要以广义复Ｈｅｒｍｉｔｅ插值样条为工具［１］（以下简称复样条），讨论了Ｃａｕｃｈｙ型奇异积分的近似计算方法和带Ｃａｕｃｈｙ核的奇异积...