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The allocation of contingency reserves is discussed in the electricity market. Three typical methods-the sequence allocating method, the allocating based the number of forced outages and the allocating based maximum output of large generators online each hour are introduced and their merits and shortcomings are analyzed and compared. On this basis the influence of various methods upon the provision of contingency reserves in units is illustrated with an example.

Pseudo Excitation Method (PEM) as a highly efficient and accurate algorithm series of stationary and nonstationary random vibration of structures has been widely used in China. Some well- concerned problems such as the seismic analysis of long-span bridges subjected to differential ground excitations, wind-induced flutter-buffet analysis of slender structures based on 3D finite element modeling have been solved and applied in some important projects taking place in China. Previously, bridges with the main span longer than 150 m were excluded in the 〈〈Specifications of Earthquake Resistant Design for Highway Engineering〉〉 (1989). Since 2008, this official document was replaced by 〈〈Guidelines for Seismic Design of Highway Bridges〉〉, in which PEM is recommended as a basic tool for seismic analysis of long-span bridges. In the design of high speed trains, random vibration can not be effectively analyzed by the traditional approach. The PEM has recently been used instead and some important progresses have been obtained.

An efficient and accuracy sensitivity analysis method for optimal analysis of random vibration of vehicle-bridge coupled system is purposed. The pseudo-excitation method is used to transform random road surface roughness into a series of deterministic harmonic excitations, and then the precise integration method is adopted to compute vehicle/bridge system response. The pseudo-excitation method and the precise integration method are both accurate and efficient, so that the first and second order sensitivity information of the responses can be obtained very conveniently. Taking ride comfort as the objective function, an optimal analysis for a vehicle/bridge system is performed.

A feasible scheduling strategy of AGC capacity has been proposed. A mathematical model of AGC operating expense is built firstly, which include fuel costs that are incurred when units are operating on basic point, capacity costs that are associated with AGC capacity reserved, and the AGC adjustment costs of units. Then, based on the model, we construct the Lagrangian function and deduce the shadow prices of AGC electricity of scheduled units and the equilibrium of the shadow prices. Last, a feasible scheduling strategy of AGC capacity is designed. The numerical experiment indicates that the strategy can allocate real-time scheduled AGC electricity fairly and reasonably, which can ensure the system perform reliably and securely, and be economical simultaneously.

A global optimization approach is put forward in the paper, which can minimize the total cost when the demands of ancillary services have been met. Based on the replacement of various of ancillary services, such as AGC, spinning reserve, non-spinning reserve and standby reserve. The highest-quality ancillary service is first met as various of ancillary services are bidding in the same time. Case studies show that the method is effective and practical, and can save more compared with the sequence approach.