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This paper investigates the problem of decentralized coordination control in the context of fractionated spacecraft free flying that drawn inspiration from the cyclic pursuit research in the field of multi-agent systems. The mathematical background and formation flying preliminaries are firstly introduced. Then, the cyclic pursuit algorithms for single-integrator and double-integrator are presented, the stability of the controller is also analyzed. The cyclic pursuit control laws to form the circular and elliptical formation are put forward. Finally, the numerical simulations of fractionated spacecraft re-gathering, reconfiguration to a circular and elliptical formation are carried out. The simulation results indicate that the cyclic pursuit control is a very promising technique for fractionated spacecraft free flying, because it is leaderless, easy for implementation, and most important of all, it only requires the local information for control.

The resource of coke oven gas is very rich in China. Electric power generation from coke oven gas is helpful to save resource and protect environment. The model of key equipments of gas turbine combined cycle was approached in the thesis. The influence of air temperature on gas turbine combined cycle when firing no matter natural gas or coke oven gas was given. The part load performance of gas turbine combined cycle was also obtained. The results show that the net power and thermal efficiency of gas turbine combined cycle are decreased after firing coke oven gas. The economic performance of gas turbine combined cycle was also evaluated, and the results show that the project has great ability to make profit.

Compressors constitute an integral part of most turbo machinery systems and are widely used in many chemical, industrial, and aerospace applications. The performance map of compressor is influenced by IGV closure angle and relative humidity of air. The calculation model of axial flow compressor is built in the paper, and the influence of IGV and relative humidity on performance map is analyzed in the paper.

Extraction steam pressure loss will occur as extraction steam flows through the pipe and the heater. The thermal economy of the unit is decreased by the occurrence of extraction steam pressure loss. Based on the basic equations of thermodynamic system, the influence of drain water enthalpy on thermal efficiency of unit is calculated in the paper, and the law of formulas is found. It is proved by the paper work that the influence of extraction steam pressure loss on thermal economy is actually the superposition of the influence of heater outlet water enthalpy and drain water enthalpy on thermal economy. Based on the paper work, the influence of extraction steam pressure loss on thermal economy of unit is built. The method discussed in the paper is not only prone to be used, but suitable for computer program. The method possesses the universal property. The general calculation formula is proved to be right by an application example.

Cooling tower outlet-water temperature concerns greatly economic and safety operation of unit. A calculation model of cooling tower outlet water temperature is discussed in the paper. The results are given in the paper. The difference between calculated value and measured value is very little. The factors, which concern the inlet and outlet water temperature of cooling tower, are analyzed from the view of cooling tower and condenser influencing each other. The result indicates that the influence of all kinds of factors on inlet water temperature is greater than on outlet water temperature. It is helpful for cooling tower and condenser to calculate exactly in off-design condition.