The equivalent viscous damping ratio and the equivalent natural frequency are obtained by comparing the system with a purely linear, spring-mass-damper system of single freedom.
通过和单自由度线性弹簧-质量-阻尼系统进行比较，得到该带裂缝梁结构的等效自然频率和等效粘滞阻尼比。
2
The natural frequency, damping ratio and mode shape of a multi-degree-of-freedom system are analyzed and the identified results are in good agreement with the theoretical values.
并针对一多自由度系统具体论述了固有频率、阻尼比和振型的识别方法，识别结果与理论结果吻合较好。
3
Identification of dynamic natural frequencies and viscosity damping coefficient for a large-scale structure in practical working condition is a very difficult problem.