^pof;
Mechanical;
Engineering,;
Xiangtan;
University,;
Xiangtan;
411105,;
China;
^pLaboratory;
of;
Computation;
and;
Simulation;
in;
Science;
and;
Engineering;
of;
Hunan;
Province;
(Xiangtan;
University),;
Xiangtan;
411105,;
China;