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Traction load modeling for urban rail transport is a fundamental work, which is a necessary technique of energy consumption statistics, energy saving analysis and equipment evaluation. Dynamic train headway is the decisive factor of traction load level. The train headway in the morning peak and evening peak is the shortest, which leads to two peak loads. This paper analyzes the distribution characteristics of the headway, then based on the cosine function, it proposes a method of describing the headway on the operating day. By nonlinear curve fitting, the local volatility of the headway with the Cauchy distribution is determined. What is more, the sliding time window method is proposed to output the simulation time, train position and its load. According to the analysis of an actual case, the stochastic simulation method, we propose can accurately describe the fluctuation characteristics and probability distribution characteristics of the traction load.

DC traction power supply system is an important part of urban rail transit. The modeling of it is not only the basis of safe operation of urban rail transit, but also provides theoretical basis for failure mechanism analysis. In order to solve the problems caused by high traffic density and long power supply distance of suburban lines in the rush hours of urban rail transit, this paper established the integrated model of rectifier units-traction network-vehicle simulation on MATLAB/Simulink platform. Taking bilateral power supply mode as an example, the starting current of multi-vehicle in different locations and times in DC traction power supply system is analyzed. By comparing the simulation results, the characteristics are distinguished between multi-vehicle starting current and remote short-circuit current effectively to protect the DC traction power supply system reliably.

In order to study the impact of limited resource and maturation time on mosquito population dynamics, we formulate a simple stage-structured mosquito population model with saturated recruitment rate, where mosquito population is divided into two class. The basic investigation of the model, such as the existence of equilibria and their stability, has been finished. The global stability of the unique endemic equilibrium has been proved. A numerical simulation has been presented too. Our findings finally show that reducing the resource and maturation time, are effective methods to control the number of mosquitoes.