multiple integral meaning in English

多重积分
重积分

Making use 0f the symmetry skill t0 calculate multiple integral
利用对称性技巧解多元函数重积分
The application of orthogonal transformation in multiple integrals
正交变换在多重积分中的应用问题
Monte - carlo method for calculating multiple integral and its optimized method
应用内外混合罚函数法
Compute the value of multiple integral by the symmetry of integral region
利用积分区域的对称性求重积分值