When using CBL-VDL logging information to carry out cement bond evaluation, formation wave energy is major sign to reflect the second interface cement degree.
在利用CB L-VDL测井资料进行水泥胶结评价时，地层波能量是反映第二界面水泥胶结好坏的主要标志。
2
When exciting Sin voltage source is applied to proper port, the stability of network depends on the sign of active and reactive components for fundamental-wave current entering port of networks.
若在适当端口施加正弦电压源，则网络的稳定性取决于进入端口基波电流的实功与虚功成份的符号值。
3
The handedness of the helical wave fronts of the LG modes is linked to the sign of the index land can be chosen by convention.