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Fast detection study of foreign object intrusion on railway track

Niu H., Hou T.

Archives of Transport

2018

Vol. 47, iss. 3

79--89

The foreign objects intrusion on railway track has seriously affected the safe operation of the train, and it is extremely urgent to monitor them in real time. In order to improve the detection accuracy and rapidity of foreign objects intrusion on railway track, the new detection method of foreign object intrusion on railway track based on multi-background modeling, multi-difference and proportion method of black and white pixels is put forward in this paper. The multi-background modeling method that includes the historical background modeling, the multi-frame average background modeling and the previous frame of current frame background modeling method is used to model background modeling, and the three backgrounds are updated respectively to achieve background updating. The improved Canny method and Hough transform method is used to extract track edge, and get the final track edge image. Based on track edge image, the railway track dangerous area was established through the image segmentation method to reduce the amount of information in image processing and improve the processing speed. And then, according to the structure method of multi-background modeling, the detection method that fuses the historical background difference, average background difference and interframe difference is used to detect foreign object intrusion on track, and the detection result was processed by the morphological open processing. Finally, for the foreign objects intrusion, the decision is done by the quantitative proportion method of black and white pixels of image. The experimental results show that this method has better noise immunity performance and environmental adaptability, and the accuracy and rapidity of foreign objects intrusion detection is improved effectively.

New application of D-π-A molecules as a sensor for recognition of Cu2+ in polluted water

Niu H., Zhu G., Zhu M., Li X.

Environment Protection Engineering

2017

Vol. 43, nr 4

67--72

Novel chromophore GZP1 with D-π-A structure was designed and prepared for its application as a sensor for the recognition of Cu2+ ions in polluted water. Reaction of aldimine condensation was used to synthesize chromophore GZP1. Its chemical structure of was characterized by mass spectrum, nuclear magnetic resonance spectroscopy and ultraviolet-visible absorption spectrum. Cu2+ ions were recognized via fluorescence spectra. Chromophore GZP1 showed specific detection ability of Cu2+. 14 other metal ions were used as reference. The detection limit was estimated to be 0.06 μmol/dm3 in aqueous solution, which was significantly lower than the typical concentration of blood Cu2+ in normal individuals and the limit of copper(II) in drinking water.