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In this investigation, micro crystalline diamond (MCD) and nanocrystalline diamond (NCD) films are deposited on cemented carbide (WC-Co) balls by hot filament chemical vapor deposition (HFCVD) technique. After deposition, MCD and NCD films are characterized by field emission scanning electron microscopy (FESEM) and Raman spectroscopy. Then frictional tests are carried out between CVD diamond coated balls and graphite. The results show that the MCD-graphite and NCD-graphite tribo-pairs exhibit comparable frictional coefficients, while the wear rate of graphite in MCD-graphite working pair is much higher than that of graphite in NCD-graphite working pair. Furthermore, the element oxygen is detected in the wear groove of graphite, suggesting the oxycarbide of working materials at the increased temperature due to the heat generated from the mechanical friction.

This Paper has analyzed the relationship between the generation of multiple piezoelectric effects and boundary conditions of piezoelectrics and the experiments have studied tertiary piezoelectric effect of piezoelectric quartz which is applied extensively in engineering practice. We processed our experiment by piezoelectric quartz crystal unit made by two pieces of X-cut piezoelectric quartz, parallel connected it to a capacitor with the equivalent capacitance of about 1,000 times of that of piezoelectric quartz crystal unit and then got the result of pure primary piezoelectric effect excluding tertiary induced effect; then compared it with conventional primary piezoelectric effect and concluded that tertiary piezoelectric effect of piezoelectric quartz is about 1.7% of primary piezoelectric effect; thus quantified longitudinally tertiary piezoelectric effect of piezoelectric quartz crystal, concluded that piezoelectric coefficient of tertiary effect of X-cut piezoelectric quartz is about 0.04 pC/N by experiment and got relative uncertainty and standard uncertainty of the results by such experiment methods respectively as 9.49×10-3and 1.37×10-2. This study on tertiary piezoelectric effect has provided a new approach for improving precision and sensitivity of piezoelectric sensors.

Lane changing is the common behavior when cars are running. It will produce traffic conflict, reduce the efficiency of road system, and lead to malignant traffic accidents. Based on the analysis and evaluation of circular, cosine type, constant lane migration type and ladder lane transformation type, considering the driver behavior, vehicles control and dynamic constraints and thinking the obstacles as an infinite number of circles to idealize them, this paper establishes polynomial in horizontal and vertical directions respectively to indicate the position of vehicle, obtains the lane changing trajectory by testing whether the distance between circles meet some conditions, builds polynomial for the safe lane changing trajectory and real-time dynamic optimal distances between vehicles, and then utilize the MATLAB as the simulation tool to make experiments in various cases. Simulations and experimental results show that the method given in this paper to calculate the vehicle safety lane changing trajectory in the case of high-speed vehicle is feasible, effective and can give quickly safety lane changing distance.

Intelligent Transportation System (ITS) is a new industry and development greatly in recent years. The advanced electro-communication and computer technology combines detection, control, active warning and other information means. It provides a great guarantee for improving traffic safety and high efficiency. This paper puts forward the traffic rate-limiting sign and Lane Mark recognition method. In this study, four steps are applied to recognize a traffic and Lane Mark sign in an image. The first step, we transform the color space of image from RGB into HIS. Then the image blended HIS and RGB information is segmented. The third step, the text restrain and eliminate the isolated noise point based on eight-neighborhood. Finally, the traffic speed-limit sign and Lane Mark is recognized with template match. Our experiment results, in the out door, show that the method mentioned in the paper is useful and effective.