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The VSC-HVDC technology, as the third generation HVDC transmission technology, is proactive and the most advanced transmission technology. The reliability of VSC-HVDC transmission system needs to be further researched since its short research duration and few projects. Based on reviewing VSC-HVDC technology development, this work investigates on the critical factors and equipment affecting normal operation. Then, the article summarizes reliability research status and presents deficiencies by contrasting with the reliability research methods for traditional HVDC transmission. Finally, combining with engineering example, some ideas and prospects for the application and development of VSC-HVDC reliability technology are proposed.

This article according to the current tendency of Chinese municipal transportation development, proposes the more reasonable solution about embedded platform. Connecting the MCU and the GPRS module through the serial ports, then transmits the AT instruction to the serial port. It causes the platform to be able to relation to the office terminal through the 3G network. Achieved that various sensors collected information in the vehicle can transmit mutually effect with the tube control center.

Based on the fabric image mosaics problem is researched. In the aspect of image edge extraction using cellular automaton model, carries on the research on the characteristics of fabric image mosaic of images, for the rough match of two images,to determine the overlapping area, in the range of the image mosaic, afterwards the image mosaic, the seam is eliminated by rapid and simple weighted smoothing algorithm between two images. Through numerical examples indicate that the method in fabric image mosaicing aspects have better effect.

Welding is developing to automatization and robotization, and robot welding is an important development direction. A robot real-time seam tracking system based on laser vision is researched, which includes laser vision sensing and seam image acquisition, seam images recognition and extraction, system coordinates calibration and transformation, communication between PC and robot, control for robot seam tracking, and robot seam tracking experiments. A way of image filtering is improved and four methods to recognize and extract seam images are studied. Lap-joint seam tracking experiments are performed to test the seam tracking system. Lap-joint groove experiment results show, corner detecting image recognition is satisfied with real-time seam tracking and has good precision and stability, and the whole system studied in the paper is satisfying for robot real-time seam tracking.

The quasi-regular patterns generated from hamiltonian has unique balanced symmetry. The patterns are quite suitable for the textile fabric. However the number of patterns just generated from hamiltonian are limited. Therefore in this paper a 110 of functions built by the methods of hamiltonian of superposition, nesting, combination and parameter variations, and it can increase the type and quantity. All of functions can generate fine patterns suited for textile fabric after computer graphics.

It is difficult that the detection of printing fabric, because the more complex color and pictorial. This article opted for the fabric color difference detection problem. This article is on the basis of analyzing of the fuzzy color, the fuzzy method can be used to describe it, proposed based on fuzzy membership function method size of the fabric color identification methods, and gave the L * a * b * color in the color model identification steps. Through simulation results show that the method proposed by the color of the fabric printing identification is feasible and effective manner.

A lot of function database were built by researching evolution law of uniform stochastic web and quasi-regular patterns mathematical model. It related quasi-regular pattern evolution mechanism with textile pattern design to translate formerly invisible information in mathematic area into visible textile pattern of art design. So the visual field on design could be effectively expanded, and formed the new design concept and thinking.

The detection of fabric color difference and classification issues are studied. First, to the question of color differences and analysis of the characteristics of different color space, we chose L * a * b * color space model. In this method color difference is converted into geometric distance, so we can detect the color difference with the corresponding calculation. For the complexity of color difference classification, we consider that the classification of color difference is fuzzy, so we use fuzzy method to describe it and fuzzy neural network to complete the classification. We also explain the algorithm and structure of fuzzy neural network. Finally, for the detection and classification of color difference of the fabric samples, characteristic and comparative analysis of the detection and classification concludes that the methods chosen are effective and feasible.

Camera calibration and robot hand-eye calibration are important parts in applications of robots with visions. A way to simultaneously carry out camera calibration and robot hand-eye calibration is presented in robot welding system with laser vision. It is based on a certain relation between hand-eye matrix and matrix of robot hand frame to robot base frame. Calibration experiments are performed in this way using specifically designed calibration objects. And all parameters to be calibrated are solved out in nonlinear least square optimization method. 3D world coordinates of 20 sample points selected from a v-groove seam are reconstructed with the calibration results. By contrasting their real coordinates, average error is 0.12 mm, which is sufficient to the requirement of robot seam tracking.

Health monitoring of the hydropower turbine and timely identification of potential failure areas can prevent failure of the entire vertical axis hydropower turbine. A health monitoring system integrated within the turbine could locate blade failures, reducing hydropower turbine life-cycle costs and the costs of energy. System health management is a concerted effort with applicability to machinery maintenance operations and support. Condition based maintenance (CBM) seeks to generate a design for a machinery CMB system that performs diagnoses and failure prediction on hydropower turbine. Eventually, a variety of monitoring systems will be instrumented with embedded high-performance processors to monitor equipment performance, diagnosis failures, and predict anticipated failures. The purpose of this paper is to discuss an approach to integrate data collection and analysis of hydropower turbine for the purpose of assessing equipment condition and maintaining their operational performance to support a system wide CBM concept in a cost effective way.

An on line monitoring and diagnosis system for a modern power plant is essential as hydropower turbine failures are rarely single mode events. Normally, hydropower turbine deterioration is a slow process involving many factors. Cavitations are most severe, eventually forcing a shutdown for repair of affected parts. Cavitations phenomenon in an operating turbine are ubiquitous and unpredictable, and much different in one type turbine from others. Cavitations are often connected with efficiency change, increase of noise level and vibrations. Consequently, early studies on cavitations detection in hydro-power turbines are indirectly based on observation or feeling of vibration pulsations on surface of the guide-vane stem, the draft tube wall, the lower guide bearing etc or intensity of acoustics emission on the turbine casing. The most feasible approach to detect cavitations must be of less influence to the normal turbine operation conditions, thus we must gain insights into its condition with a nondestructive technique (NDT). The aim in the present paper is to develop an adequate monitoring and diagnosis system on line based on NDT to detect the cavitations occurrence and to quantify its aggressiveness in order to optimize turbine operation and to extend inspections and repairs interval.