longitudinal arch
1.thelongitudinal direction angle of lateral mass to sagittal plane was 16.43±2.00o,the longitudinal direction angle of C1 posterior arch to horizontal plane was6.12±2.15° (range -0.2°~14.6°).
2.It is found that the boundary element method has many advantages over the finite element method and that the longitudinal stress affecting the stability of rock masses varies evidently along the boundary of an arch drift.
3.A new waveguide made of changing a wide wall of a rectangular waveguide to a uniform curved wall is called conformal waveguide.A kind of expression of approximate solution for domain mode of the new waveguide,including symmetric,unsymmetric arc,parabolic arch,hyperbolic arch,elliptic arch,etc.,is constructed by using boundary condition of mental waveguide,variational method and boundary element method.By using the equivalence principle,an approximate calculating formula for equivalent resonant conductance of a narrow longitudinal halfwavelength slot cut in the curved wall of the unsymmetric arcrectangular waveguide is derived,and the result is shown.Although this solution is approximate,it can solve the problem in designing the slotted antenna of such conformal waveguide.
