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A flexible traction power system is proposed for AC-fed railway due to its benefits in power flow optimisation, online catenary anti-icing and power quality improvement. In this system, an energy optimisation controller in section post is adopted to provide reactive anti-icing current and control the energy flow in regenerative braking of the locomotives. The energy optimisation controller in traction substations is adopted to eliminate three-phase unbalance in power grid and perform reactive power compensation. The mathematic model of the proposed system is built based on a power transformation analysis and the validity of compensation algorithms is verified by case studies.

According to the project interface risk classification including the physical interface risk, the contract interface risk, the tissue interface risk and the information interface risk, the integrated management model of project interface risk was put forward, which focused on the three dimensions: time dimension, relational dimension and information dimension. The project interface risk management system was developed, which consists of information subsystem, organizational subsystem, resources and support subsystem, and dynamic management subsystem. The system implements integration of project risk management from the perspective of the interface, and by using the system managers can foresee the exact location of the risk occurring or may occur.

Laboratory-scale carbon anodes were produced by a new method of high temperature mould pressing, and their physico-chemical properties were studied. The influence of mould pressing conditions and coal pitch addition on the bulk density, crushing strength, and oxidation resistance was analyzed. The microstructure of carbon anodes was investigated by scanning electron microscopy (SEM), and the mechanism of producing carbon anodes by high-temperature mould pressing was analyzed. The results show that when the anodes are produced by high-temperature mould pressing, coal pitch can expand into the coke particles and fill the pores inside the particles, which is beneficial for improving the quality of prebaked anodes. The bulk density of carbon anodes is 1.64–1.66 g/cm 3 , which is 0.08–0.12 g/cm 3 higher than that of industrial anodes, and the oxidation resistance of carbon anodes is also significantly improved.

The rapid urbanization in China has caused significant urban land use changes and extensive urban growth these years. That has led to a dramatic decrease in arable land and would challenge the national food security. To understand the anthropogenic driving forces of urban growth and find out effective control methods, this study established the Hierarchical Liner Model (HLM) to explore the influence of such factors including society and economy, population, and industry development. On the base of factor analysis and HLM, the decomposition of the affecting factors for urban growth was performed, it visually shows that the social retail goods, public transit passengers, and nonagricultural populations significantly drove the urban growth in China; the tertiary industry development has weak effects on urban growth. By weighting the role of the anthropogenic factors on urban growth, some advices were given at last, and it could provide possible management options for the government to mitigate the excessive urban growth in the near future.

According to the principle of muscular hydrostats, a flexible biomimetic octopus arm is put forward firstly. The method of vector control for the flexible biomimetic octopus arm is presented and analysed in detail. Based on the combination of ARM (advanced RISC microprocessor) and FPGA (Field Programmable Gate Arry), a control system for the flexibie biomiometic octopus arm is discussed, and the functions of every components is analysed. To verify the feasibility and reliability of the method of vector control, experimets are carried out. The experimemtal results demonstrate that this method applied in the control of the biomimetic octopus arm has a good performance.

Based on characteristics of environmental impact of railway construction projects, the paper drew on experience of environmental impact assessment (EIA) projects, carried out preliminary EIA on China's mid-long term railway network plan from macro perspective according to planning requirements, and discussed the key points of EIA on guiding special planning.

The outstanding power quality problems including three-phase voltage unbalance and large reactive power have drawn more and more attention of railway company and power system. Moreover, the neutral section insulators at exits of substations affect the safety and efficiency of the electric trains, especially in high speed railway and heavy haul railway. A new traction power supply system adopting Vx connection traction transformer and active power flow controller (PFC) is proposed. The mathematic model of the new system is built and the compensation currents of PFC are calculated for comprehensive compensation. Moreover, the optimized topology and control method of PFC are studied. The simulation and performance of the different operation modes verify the validity of the proposed system, which can be used in high speed and heave haul railways.

Credit sale acts a very important role in the operation of one company. Nowadays, in order to reduce the credit risks, ensure the benefits of companies, and communicate effectively with the customers, analysis of customerspsila credit has become a very popular research question. In this paper, the author develops a credit evaluation model for medicament enterprise based on data mining methods clustering and neural network. By using this model, a company can predict that if the customer will default of contract.