Vibration it can be very harmful – leading to eventual failure of the system. Consequently, one of the major reasons for vibration analysis is to predict when this type of resonance may occur and then to determine what steps to take to prevent it from occurring. As the amplitude plot shows, adding damping can significantly reduce the magnitude of the vibration. Also, the magnitude can be reduced if the natural frequency can be shifted away from the forcing frequency by changing the stiffness or mass of the system. If the system cannot be changed, perhaps the forcing frequency can be shifted
Shannon capacity of a graph "α"("G"). The effective number of signals transmitted per unit time step is the "k"th root of this number, "α"("G"). Using these concepts, the Shannon capacity may be defined as the limit (as "k" becomes arbitrarily large) of the effective number of signals per time step of arbitrarily long confusion-free codes. The computational complexity of the Shannon capacity is unknown, and even the value of the Shannon capacity for certain small graphs such as "C" (a cycle graph of seven vertices) remains unknown. A natural approach to this problem would be to compute a finite number of powers of the given