By using the methods of co-integration, impulse response function and variance decomposition, I conduct the empirical research on the dynamic relationship among
On the basis of overview of the study area,by analyzing the dynamic change of farmland in Ninglang County,we can find that the farmland area in this county tend
Traditionally, the transmission device for cutter adopts gear mechanism combined with planar crank-rocker mechanism. In line with this drawback, this paper pres