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Aiming at the de-noising of GPR echo signal, a de-noising method based on EEMD and wavelet is presented. First the echo signal data is processed with EEMD and yields IMF components. Then the IMF components which indicate noise are subtracted. Next, the high frequency IMF components of the remaining are subjected to wavelet threshold. Finally, the signal is reconstructed using the de-noising IMF and low frequency IMF to realize signal de-noising. Compared with other commonly used methods, EEMD-wavelet method has improvement on SNR. The experiment results show its effectiveness and feasibility in GPR de-noising.

This paper has introduced the clustering algorithm into the model of urban tourism destination consumption structure, and has used MATLAB programming algorithm to improve the calculation model of consumption structure for tourism destination, which has obtained the spatial data model of the consumption structure. The model roundly considers the influence of geographical location, cultural factors, political factors and economic factors, and it establishes new clustering algorithm model with four coefficients, and has realized the algorithm by the use of MATLAB programming. Finally, the consumption structure of the same destination in different provinces is calculated by using the spatial system model, which has obtained the calculation curve of consumption space structure and the clustering results, and has provided technical reference for the research on consumption of urban tourism destination.

This paper has designed a new diamond computer evaluation method by the use of the diamond evaluation model, and the combination of VC programming technology, and the method has been introduced into the evaluation of regional tourism comprehensive competitiveness. In order to achieve the comprehensive evaluation function of new diamond model, we have designed new diamond comprehensive fuzzy evaluation model by using fuzzy evaluation function to, and have the developed computer evaluation system of regional tourism competitiveness by combining VC programming technology. The system uses the market, enterprises and infrastructure the three aspects of evaluation factors to score the tourism competitiveness, which has realized the evaluation of computer automation function. Competitiveness of regional tourism industry in Shandong, Yunnan and Gansu and other areas is respectively scored through the function, and the results indicate that the comprehensive evaluation score of Yunnan is the highest, and that of Gansu is the lowest.

By analysis the causal relationship of the public health emergency actions and effects, then establish a generalized model for the prevention and control of public health emergencies by Timed Influence Net (TIN), and on this basis of probability reasoning, inference result can assist analysis the pros and cons the emergency scenario. Method was applied to the example of SARS outbreak in Beijing in 2003 to show the rationality and validity of proposed method. According to the results have a study on the optimization of emergency scenario, optimized conditions comparative and analysis with the actual program. The results show that the proposed method can better support emergency scenario evaluation and optimization.

In Chinas semi-deregulated electricity market, a game-theoretic model has been set between users and power suppliers in order to ensure the whole network voltage load curve stay smooth, as well as to make the suppliers profitable on the basis of the satisfaction of users in power utilization in daily lives. The foundation of the model is the definition of the price elasticity of demand and its characters in micro-economy. According to this model, a Bayesian Nash equilibrium has been put forward based on the demand price elasticity, which can not only smooth the whole network voltage load curve effectively through the reciprocal process between users and power suppliers, but also can optimize the profit of the power suppliers. The simulation results of the voltage load curves and price changes graphs show the effectiveness of modeling simulation.

In this paper, a new control scheme of a variable speed grid connected wind energy generation system was presented. The scheme used a squirrel-cage induction generator (SCIG) as generator and it connected to the grid through a back-to-back double PWM converter. According to the characteristics of induction motor, the generator side adopted rotor flux linkage oriented slip frequency vector control technology, and the grid side used the network voltage oriented control and voltage and current dual close-loop control strategy. The simulation results show that the system can work in the state of variable speed constant frequency (VSCF)power generation and the active and reactive power can be controlled with no mutual interference and with good static-dynamic performance.

This paper proposes a novel rotor position estimation method based on line back EMF for brushless DC motor (BLDCM). The relationship between position phase error and the symmetric line back EMF is analyzed. It is noted that line back EMF error can exactly reflect rotor position phase error. If the amplitude of line back EMF at the beginning of commutation is equal to the amplitude of line back EMF at the end of commutation, the waveform of line back EMF should be symmetric. Based on the above analysis, a closed loop control method to correct rotor position phase is presented. Line back EMF error is employed to keep the waveform of line back EMF symmetrical by PI controller. This paper also develops a sensorless BLDCM driver to implement the proposed method based on DSP and the experimental results prove the validity of the proposed method.

The mathematical model of the grid-side converter is analyzed. A control system of the grid-side converter used in 7.5kW doubly-fed wind power generation simulation test platform is designed. The TI TMS320F28335 DSP is choosing to be the main controller. The decoupled control and the double closed loops control are adapted in the system. The control strategies of stabilizing DC-link voltage and unity power factor control operating at sub-synchronous and super-synchronous state are realized. The experimental results show that the mathematical model and control strategies are correct and effective.