Through analyzing causes coming into being strand torsion of tubal strander and courses of self-elimination of torsion,it is thought that self-elimination of torsion and purposeful pre-torsion of rope and strand during stranding of tubal strander are effective measures to prevent loose and tight strand and it is unsuitable to install turing frame on the rocking frame of tubal strander.

Hence the shearing force flow of themulticell closed thin walled member under pure torsion is evaluated directly.

There are shear stresses as well as normal stresses,which can be neglected in the cases of small deformation,on the section of round straight bar under free torsion.

Study on ICI self-cancellation algorithm of OFDM systems;