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There are many wetland resources in the area where the Yellow River enters the sea. This area has good ecological and economic value. Therefore, wetlands are precious resources. The accuracy of traditional wetland classification methods is low (for example, based on the support machine method). In order to explore ways to improve the accuracy of wetland classification, this paper selected the wetland at the mouth of the Yellow River as the study area. And, we used the hyperspectral data of “Zhuhai No. 1” as the research data. Then, we used the logarithmic transformation method to enhance the spectral characteristics of remote-sensing images. Finally, we used Markov random field method (MRF) and support vector machine method (SVM) to finely classify the wetlands in the Yellow River estuary area. We used these experiments to explore wetland classification methods for hyperspectral data. The results showed that the settings of the coupling coefficient and the initial value in the Markov model had a greater impact on the classification results. We found that the best result was when the initial classification number is 50 and the coupling coefficient is 0.5. Compared with the SVM classification method, the overall classification accuracy of our proposed method was improved by 3.9672%, and the Kappa coefficient was improved by 0.042.

In 2008, Beijing Electric Power Supply Company completed the construction of communication operation management information system, which greatly improved the management ability of power communication and provided strong support to the 29th Olympic Games and the 60th anniversary of People′s Republic of China. Based on the current situation of power communication network and combined with the requirements both from the construction of smart grid and the development of information system, this paper discusses the process of power information and telecommunication development, analyses key problems and put forward the solutions. With the experience of the construction telecommunication information system of Beijing Electric Power Supply Company, the system architecture and functions are also discussed. It has reference value for the construction of communication operation management system in power system.

This paper firstly introduces the standard models and key control techniques of microgrids. And then the battery energy storage and superconducting magnetic energy storage (SMES) charge-discharge principles and control strategies are discussed, and further more build the simulation models in PSCAD/EMTDC to analyze dynamic characteristics. A combination of energy storage model is built based on the different characteristics, and realize the unity of control. The study is focused on the operational characteristics of microgrids and composite energy storages during the process of connected operation switching to isolated operation and again to the connected operation. The results show that the composite energy storage has both the two energy storage advantages, it can response rapidly, balance the power flow, stable voltage fluctuation and meet the load demand of power supply. It ensures the stable operation of microgrids.