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This paper mainly studies the design and implement of mobile meter reading system based on SOA. The mobile terminal can save offline power reading data in its local database and communicate online recorded data with the server through Web service interface based on the internet. The Web service components perform interaction with the database server. This system is developed by using programming language Java and embedded database SQLite on Android platform. This mobile application can be available to download customers' data from the server or update new meter reading data to the server and then the operators can accomplish their works conveniently during the interviewing with the customers without going back to the office.

In order to adapt to the demand of integration and sharing about electrical power school and to break the limitation of "Islands of information", it is necessary to develop a loosely coupled information system. This paper introduces the system application demand of electrical power school, and designs the functions of the system and scientific object-oriented data model. A concept of operating mode information system is designed based on cloud computing. Object-oriented programming language C# is used to develop the prototype of the system. The result of application is showed in various UI. This paper provides a valuable reference for the information technology future about electrical power school

Power semiconductor device and its control circuit of photovoltaic grid-connected inverter is the weakest part in the photovoltaic generation system. Fault feature extraction is the key to the inverter fault diagnosis. Output voltage of inverter is the most sensitive characteristic quantity which can reflect its working status directly. The single transistor open fault diagnosis of photovoltaic grid-connected inverter can be achieved by extracting the output voltage frequency spectrum with the help of windowed STFT. The simulation results demonstrate the effectiveness of the method.

Malfunction such as target non-reach ability, local minimum pole and oscillation happens when traditional APF is applied to route planning. This paper proposes an improved APF model, considering the relative distance between the UAV and the target, the relative distance between the lead craft and the wing craft and the safety. We ensure the point of target to be the global minimum point in the entire potential fieldtarget non-reach ability caused by the threat and target point being too close are solved by adopting the modified repulsive potential function; planning failure in which UAVs falling into local minimum point is solved by adopting random fluctuation method; considering the oscillation of traditional potential field, the obstacle link method is proposed. The results of the simulation indicate the single UAV simulation route after obstacles overall planning, track route of UAV formation and formation route with obstacles with turning angle constraints. Requirements of Formation control and formation obstacle avoidance have been well satisfied.

Along with the rapid development of correlative technology in the 21st century comes the upsurge of research and exploitation for stratospheric airship around the world. In this paper, on the basis of the unique strengths of stratospheric airship, we analysed its prospects of application in the fields of communication and earth observation. Besides, we explored the status quo of development and key techniques concerning the stratospheric airship, which lead a significant role in the reference and guidance for future development of advanced information technology and building of national defence.