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Egineering running experience shows that with the increase of the operating voltage of the transmission line, the lightning trip rate is increasing. According to theoretical calculation ， UHV transmission lines should be provided with full lightning protection characteristics；however，running experience shows that the lightning withstand level of UHV transmission lines is high，not completely lightning protection; it puts forward higher requirements for lightning protection design of UHV transmission line in China. UHV transmission line is mainly against direct lightning stroke characteristics， one is caused by lightning counterattack trip，the other is the shielding failure of lightning around the line to strike the wound caused by the wire. The lightning fault type identification is based on the micro topography of UHV transmission tower，accumulation of historical data，the development of a more targeted and high voltage transmission line lightning protection scheme is of great significance. In this paper, a real-time identification system based on UV detection technology, which has high accuracy and fast response time, is proposed for lightning fault types of UHV transmission lines, the systems use ultraviolet light to realize online detection of high-voltage transmission line tower nearby lightning, can effective observation tower near lightning discharge, and it has the characteristics of continuous detection, longdistance, no power supply, no contact and no disassembly, it provides an advanced technology for the detection of lightning discharge in UHV transmission line.

This paper addresses the role of governments, industry, academics, and non-governmental organizations in Food Fraud prevention. Before providing strategic concepts for governments and authorities, definitions of Food Fraud are reviewed and discussed. Next there is a review of Food Fraud activities by the Global Food Safety Initiative (GFSI), the Elliott Review in the United Kingdom, the European Commission resolution on Food Fraud, and the US Food Safety Modernization Act including the Preventative Controls Rule. Two key concepts for governments or a company are: (1) formally, and specifically, mention food fraud as a food issue and (2) create an enterprise-wide Food Fraud prevention plan. The research includes a case study of the implementation of the concepts by a state or provincial agency. This analysis provides a foundation to review the role of science and technology in detection, deterrence and then contributing to prevention.

Based on the standardized modelling of the International Modelling Team, study on double-fed induction generator (DFIG) wind turbine is processed in this paper, aiming at capability of universally and reasonably reflecting key performance related to large scale system analysis. The standardized model proposed is of high degree of structural modularity, easy functional extension and universalization of control strategy and signal. Moreover, it is applicable for wind turbines produced by different manufacturers through model parameter adjustment. The complexity of the model can meet both needs of grid-connected characteristic simulation of wind turbine and large scale power system simulation.