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Design and implementation of system of wireless-monitoring for goods train is based on ZigBee technology. The system is consisted of ZigBee monitoring nodes on-site and handheld display terminal. The JN5139 wireless microprocessor is used as the master controller for ZigBee monitoring nodes, which is produced by JENNIC Ltd. in Britain. ZigBee device nodes automatically form wireless sensor networks, and use door magnetic sensor circuit which has high sensitivity and fast response to monitor the status of the door. The alarm information about the status of the door will be transmitted to the handheld wireless terminal to display and alarm. RFID technology is useful in conditions that mobile and car numbers are arbitrarily setted for freight transport in the process of practical design. Furthermore, modular design is used to facilitate the maintenance of the system and improve the capabilities of real-time, reliability, stability and anti-jamming.

This paper proposed a railway wagon anti-theft system based on ZigBee technology. The system was consisted of Handheld device, Router and End device. The Handheld device was mainly used for the configuration of the net and initialization. The Router was used to relay the message between the Handheld device and End device. The End device was a monitoring node. The CC2430 microprocessor was the controller of the system. The magnetic sensor was used to monitor the status of the wagon door. The alarm information would be transmitted to the Handheld device to display and alarm. RFID technology was used to mark the number of train carriages. In addition, GPRS module was used for transmitting the wagon information to the remote PC, and finishing wireless long-distance monitor. The experiments verify the reliability of the system. It is proved that the system has a certain application value.

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Wind tunnel test can not simulate effectively the flow field of fuze electrical machinery at flight test conditions. In order to deeply research the structure of flow field and measure the flow field density out of fuze electrical machinery, the laser dual hologram interferometry was applied and the streaks photos were obtained clearly. To recognize the contours of density field, identification is needed to deal with interference streaks, and the density of local streaks is calculated with interference principle. The hologram interferometry photos of density field were pro-processed in the thesis, for the problem of photos that the left part was much brighter than the right, the method of multiple threshold was used to binary image. It can be seen that the method gives consistent results to a certain extent of human perception and gives ideal results to find uniform regions in the image plane. Then the binary image is thinned by pixels searching algorithm according to the lines to get coordinates of the pixels of each streak and to lay the foundation for extracting density field from density interference streak in future research.