This paper concerns the development and application of the Hamiltonian function which is the sum of kinetic energy and potential energy of the system. Two dimen
Currently, domestic and abroad scholars put more attention on contra-rotating dual-rotor axial fan. But there is less scholars study on asymmetric dual-rotor sm
Extending the work carried out by [1], this paper proposes six combined-type estimators of population ratio of two variables in post-stratified sampling scheme,