The inevitable objection raised, is that the apparently closed system produced by this arrangement cannot result in an output force, but will merely produce strain within the waveguide walls.
必定有人提出反对意见：显然，封闭系统不能输出对外的推力，但只会产生应变在波导内墙壁。
2
The cutoff wavelength of ridge waveguide is very closed to the ridge position. It can be changed by changing the ridge position.
脊波导的截止波长与脊位置密切相关，其值可通过脊位置的改变而改变。
3
The coplanar waveguide on the substrate with finite dimensions is a physical model which is very closed to the engineering situation.