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To avoid possible conflicts between the maintenance scheduling and the unit commitment for hydro-thermal power systems under the traditional non-collaborative optimization mode,a collaborative maintenance scheduling and unit commitment model for hydro-thermal systems is proposed,in which the total cost of the system and the adjustment cost of maintenance scheduling as an objective are minimized with considering the coupling characteristics of cascade hydropower. Furthermore,the model is transformed into a mixed integer linear programming (MILP) model. To improve the solution of the MILP model,the objective scaling ensemble approach is proposed,including two stages. In the first stage,the coefficients of integer variables in the objective are scaled and the integer variables that may take 0 are probed. In the second stage,the reduced MILP model is solved after determining and fixing the integer variables with a value of 0. Finally,a 6-unit hydro-thermal power system and an actual provincial 86-unit hydro-thermal power system are taken as test systems. The results show that the proposed model can obtain a more economical and reasonable maintenance scheduling and unit commitment scheme compared with the non-collaborative optimization mode,thus effectively improving the solution speed by the objective scaling ensemble approach.

[Introduction] Aiming at allocating renewable energy consumption responsibility weight problem among market subjects, an allocation method based on evolutionary game and stochastic optimization is proposed. [Method] First of all, each market subject was taken as a limited rational individual participate in the weakly linked evolutionary game, and the absorption weight undertaking scheme that minimizes its own cost in the evolutionary equilibriumwas obtained and the selection strategy tendency of each market subject under the probability interval of different rewards and punishments adopted by the government was obtained. Then, after getting the probability interval of different reward and punishment measures taken by the government, a stochastic optimization model was used to get the specific scheme of absorbing weight which couldminimize the cost of each subject in each probability interval. [Result] The effectiveness and practicability of the proposed method is verified by calculating the data of 170 market entities in a provincial power grid. [Conclusion] A new method and idea on the weight distribution method of renewable energy absorption responsibility is provided, and feasible suggestions for the government to strengthen the enthusiasm of market subjects in the absorption of renewable energyare put forward in this paper.

High-speed maglev system is a hot research topic nowadays in the field of high-speed ground transportation. Characteristics of the track irregularity of high-speed maglev system is quite different due to its contactless vehicle-rail relationship and segmented track compared with traditional railway. However, research on maglev track irregularity is still insufficient. This paper summarises, for the first time, the track inspection data collected on Shanghai Maglev Demonstration Line (Shanghai Line) since 2006, and describes the main filtering methods and parameters for acceleration and gap signals, taking into account the characteristics of maglev track. Track irregularity is then determined using the inertial measurement principle. The measured track spectrum on Shanghai Line calculated by the Welch method obeys a chi-square distribution with 2 degrees of freedom, indicating that different track qualities can be transformed by probability methods according to the research requirements. Based on the samples obtained over the past 15 years, and referring to the seven-parameter model of the railway system, a high-speed maglev track spectrum is obtained by the fitting method, parameters of which are obtained by applying the damped least squares method. Preliminary vehicle dynamic analysis is conducted utilising the inverted excitations derived from the measured spectrum of the Shanghai Line. [ABSTRACT FROM AUTHOR]