So the importance of the problem turns academia into focus on the transition from static defense unity to active prevention architecture, among which goes one possible way to the combination of the active networking and DDoS prevention system.

The ways to imporove the efficiency of de SO 2 and low the system resistance have been put forward at last.

The feasibility to simulate the initial earth stress of the large underground structure by using the algorithm of dynamic relaxation and system damping in LS-DYNA is investigated.

Based on a simplified model of a self-synchronous mechanical system,the influence of system damping on the steady-state rotational speed of non-ideal system is analyzed,including vertically translating damping and eccentric rotor\'s rotary damping.

For the important characteristic of the source system impedance applied in the power system, a novel method of on-line measurement for the source system impedance is proposed, which utilized the dynamic process of spontaneous short-circuit of the rectifier current transition.

It considers that the economic and feasible measures that decrease the voltage fluctuation of the bus bar are to reduce the system impedance and reasonably distribute impacting load users.

Introducing the principle of adaptive instantaneous trip current protection,the discrimination method of short circuit fault type,the real time and on-line calculation method of system impedance,the calculation method of jump-value of current and the protection area of adaptive instantaneous trip current protection respectively.