Current police methods can only scan the ridgepattern to compare with database records.
警方现在使用的方法只能扫描突起的纹线，与数据库记录比较。
2
The paper computes the cutoff wavelength and field pattern at different ridge positions in asymmetric single ridge waveguide and L-shape waveguide. Some computational data and figures are presented.
The mountain wave induced by a ridge in two-layer stratifiedfliud has been successfully simulated in a tank . The wave pattern is almost the same compared with the linear theory result qualitatively.