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In order to maintain power quality and system reliability, distributed power supply system must maintain the dynamic balance of power, energy storage systems ensure stable and reliable quality of power supply system. This paper briefly analyzed the current situation and development of energy storage technologies, described the meaning and value of distributed power supply system suitable for ultra capacitors and lithium hybrid energy storage structural studies, more comprehensive descripted common models of the super capacitors, lithium batteries and accumulators illustrate, and compared the advantages and shortcomings.

The coal information system based on the electric power line was put forward after analyzing briefly the structure of mine distribution power network in roadway underground, connected with communication and monitoring networks existed already. The system uses a multi-level distributed bus network structure, roadway where harsh conditions, using a combination of multi-carrier and spread spectrum technology to overcome channel interference, orthogonal frequency division multiplexing ability to increase resistance of inter-symbol interference, wideband multi-carrier digital communications technology to improve mine of information processing ability. The system make use of the integrated services digital network to improve the security and economic value of the line, improve system compatibility, and build automation systems including integrated digital control system. Finally, the article describes the experiment and analysis based on spread spectrum modulation on power line as the data transmission medium.

Customer Participation has become a relatively mature theory in marketing with its fast development in the recent 30 years. This article brings this theory into the research of service innovation in tourism and holds the view that customer participation has changed into an important dimension in it. The external causes can be found in that it follows the shifting background setting from product economy to service economy, conforms to the competitive customer-centered environment in present-day hospitality industry, embodies the latest international trend in innovation theory and gains the full support of modern information technology. The fact that it represents the essence of all-round customer experience in modern tourism, helps the service providers with the actualization of their economic and social values, satisfies the mental needs of the service consumers accounts for the internal causes. The four basic and evaluative conclusions that the paper draws is that the atmosphere for tourism service innovation with customer participation is well-formed, it is high time to innovate tourism service to make customer participation a mainstream in the industry, and more researches on China's local practice of customer service innovation and cross-disciplinary studies are required. But meanwhile the author points out the limitations of the theory as a new perspective in tourism service innovation and warns the impossibility of it as a therapy to all problems.

The measure system in power plant based on Orthogonal frequency division multiplexing technology was put forward after the signal sources are described firstly, connected with communication and monitoring networks existed already. In this system, wireless sensor networks or carrier transmission on power line or fiber-optic is used in fully mechanized working face and electric power line systems is used as broadband networks in order to make complete signal transmission system. This system has the advantages of economy,cheapness, good protective measure and “No New Wire”, and exploit the advantage of OFDM, such as strong anti-interference. We compared the typical wavelet basses in practical application, analyzed the effects of the orthogonal bases and its character of orthogonality, compactly supported and vanishing moments in system. System structure of the powered support’ communication system and hardware design, main motion flow of the monitoring equipment were pointed out in this paper.

Sources of interference in power line are summarized. An adaptive approach to suppression of the harmonic currents based on the classical way of harmonic injection and artificial neural network is presented in this paper. The ANN keep in contact with inputs and its weights are adjusted through BP algorithms,its output can vary adaptively with the input. Membership functions of fuzzy neural variables and control rules are shown. The computing load is not very large compared with the traditional methods. It is a new use of the control system based on fuzzy neural control. This method builds a harmonic-suppression system and uses active power filter and power filter to realize power line communication based on ElectroMagnetic Compatibility.

—The electromagnetic environment of the main features in power plants is analyzed, and then the communication system based on OFDM technology was put forward in this paper, the way of selection the wavelet bases function to pass the signal communication system is discussed in the last. The system uses OFDM technology to remove the signal noise in which the cosine carriers of the conventional OFDM system are replaced by the multi-scale orthogonal wavelets transformation, and proposed the use of multi-carrier data transmission strategy, using data classification sub-carrier transmission according to the purpose and nature of the data, the sub-carrier independent of each other. This system exploits the advantage of OFDM, such as strong anti-interference. We compared the typical wavelet basses in practical application, analyzed the effects of the orthogonal bases and its character of orthogonality, compactly supported and vanishing moments in system. The common method for choosing wavelet bases, how to calculate future and direction of development is pointed out.

The power plant communication system based on Orthogonal frequency division multiplexing technology was put forward, connected with communication and monitoring networks existed already, in which the cosine carriers of the conventional OFDM system are replaced by the multi-scale orthogonal wavelets transformation. In this system, wireless sensor networks or carrier transmission on low voltage power line communication is used and electric power line systems is used as broadband networks in the main lane in order to make complete signal transmission system under well. This system exploits the advantage of OFDM, such as strong anti-interference. We compared the typical wavelet basses in practical application, analyzed the effects of the orthogonal bases and its character of orthogonality, compactly supported and vanishing moments in system. This paper discussed how to select wavelet basis when we adopt the system of OFDM based on wavelet in power plant. In OFDM system, it is important to choose the wavelet bases with batter orthogonality and larger vanishing moments.

More and more large amounts of data shared with researchers and workstations worldwide are generated by scientific experiments and engineering applications. High performance grids aim at facilitating the distribution of such data to geographically remote places. For high performance data grids where users require remote access to large files, dynamic replication is an efficient method to improve performance. In this paper, Fast Cascading, a new dynamic replication algorithm, is proposed for the multi-tier Data Grid. The simulation results obtained by Simulator OptorSim which has been modified show that this algorithm can reduce the average response time of data access greatly for random access pattern compared with other algorithms,such as Fast Spread, LRU and Economy-Zipf dynamic replication strategy, and the gain increases with the number of jobs submitted.

In this paper the chirp signals are analyzed by time-varying autoregressive (AR) model according to their characteristics, and the recursive least squares algorithm is considered to estimate time-varying coefficients of AR model. The method has the advantage of simple, saving computation time and storage space. Theoretical analysis and simulation results all show the validity of this method.