A railway monitoring system firstly includes an optical fiber. A first part of the fiber is attachable to one of a pair of tracks of a rail, and a characteristic of the first part of the fiber is variable in correspondence to variance of a characteristic of said one track where the first part of fib.....
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The utility model provides a caution board including a rating plate, a luminous caution device, an acoustic caution device and a caution control unit. The utility model has the advantages that the caution board with an audible-visual device has a simple structure, and is easy to identify and availab.....
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Disclosed is an extendible emergency bump guard post arranged underground comprising a base with open top, a post placed in the base not in use and in vertical place in use and a protecting hood movably connected with one end of the base, wherein when the post is located in the vertical or horizonta.....
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The invention provides a side emitting light emitting diode light source within the lens. Its role is to change the light emitting diode chip emitting direction, most of the light from the side of the light emitting diode chip along the central vertical axis of the very small angle inward gathered a.....
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Faced with the problem of the present invention: For the catalyst carrier, not only requires a proper specific surface area and pore size distribution, but also to support the mechanical strength and thermal stability is also very strict requirements. Furthermore, the catalytic composition and prope.....
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