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With the development of the smart grid, the security and reliability of power communication are directly related to the safe reliable operation of power system. Not only are enough power communication communications capabilities required in power system production operation sector, but also high reliability. The richness of communication reliability research methods will help improve the reliability of electric power communication management. This paper summarizes the power communication reliability research methods and analyzes their advantages and disadvantages, which is benefit for the guidance of network reliability assessment under the actual operation.

Nowadays, communication protocols are used in safety-critical automotive applications. Among the communication protocols, FlexRay, with real-time and reliable characters, is expected to become the communication backbone for future automotive systems. Therefore, a DC motor speed control system based on FlexRay network is presented in this paper to verify these characters. The following works have been done in this paper: study the FlexRay protocol specification, design the structure, programming, analyze the test results to get transmission delay time. Using the test system, FlexRay network was verified that message can be transferred quickly and correctly.

Though the prestress degree that is selected under control of the specified stress limit is a key design parameter in design of the prestressed concrete bridges, study on long-term deformation of the long span prestressed concrete beam bridges is not popular both here and abroad. This paper reveals the time-dependent regularity of long-term stress and deformation effect to the critical sections of the long span prestressed bridges from various prestress degrees, thereby the necessity of stress and deformation control consideration during design of the long span prestressed bridge structures is verified, and the prestressing expression based on stress and deflection control for relative study and design reference is given.

Construction quality of epoxy-bonded steel plates is not easy to check for absence of inspection standard in situ. In this paper inspection methods of the critical evaluation factor-bond compactness of epoxy- bonded steel plates, hammer test based multi-level grids and infrared holography, are proposed by theory analysis ,specimen experiments and practical validation in engineering. In final he suggestion on the practical usage of these two methods are also presented.