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Through the Merlot wavelet periodic analysis and Mann-Kendall mutation analysis about the maximum wind speed of 14 weather station in Hexi corridor over the past 41 years,the evolution characteristic of the maximum wind speed can be gotten:the Hexi corridor has about 28-29 years main period and 8-12 years secondary period,presenting sinusoidal curve,and the transformation energy cycled from small to big to small to big;After 1980,there were abrupt changes and decline in Anxi,Jiuquan,Zhangye and Wuwei.The Hexi corridor is in the wind speed environment of same climate conditions,and the inter-annual change feature becomes balanced; but in internal local areas,due to the influence of environment, terrain and urban heat island effect,the secondary period is different,presenting abrupt changes and decreasing tendency in 1980s.

On the base of appraising synthetically of measuring and testing technique and the monitoring system of thickness, the article analyzed the demand of thickness deviation. It also determined the control core of single chip, and studied on the on-line monitoring system of the wood-based Panel thickness, which is measured by laser sensor and differential transformer sensor and based on the technique of wireless sensors in order to develop monitoring precision and automation standard of blank thickness in wood-based panel industry.

Wood plastic composites (WPCs) are the industrial products. It is made out of wood waste fibre and waste plastic glued together by heat and pressure. Nowadays WPCs products are preferred over solid wood in many applications due to certain comparative advantages. Sawing is the machining operation frequently used in manufacturing parts of WPCs. The aim of this article is to study the effect of cutting speed on surface roughness in different WPCs sawing. A plan of WPCs sawing experiments was preformed with prefixed cutting parameters. The objective was to establish correlation between rice hull flour/PE composite, rice hull flour/PP, rice hull flour/PVC and cutting speed with the surface roughness after sawing. The results show that the spindle speed had significant effects on the surface qualities of rice hull flour/PE composites, rice hull flour/PVC composites and rice hull flour/PP composites. The advantage of using a high cutting speed in WPCs sawing is evident. With appropriate cutting parameters, one can obtain surfaces with Ra＜6μm and to get surfaces qualities (dimensional precision) in workpiece of different WPCs.