The transverse iris of a rectangular waveguide is analyzed by the full wave technique,and combined with the design theory of the filter,the iris is equivalent to an impedance inverter,whose parameter is obtained by full wave analysis,and then a transcendental equation is established by equaling the inverter parameter obtained by the filer synthesis theory with the former.

Based on analyzing the diminutive relationship of bus running time and link flow, and the limited capacity for bus, the concept of congestion function was proposed to describe the relation of trip resistance and flow, transit network resistance was investigated combined with transit time chain.