An auto on line safety valve checking and adjustment system is developed to solve the problems of poor degree of accuracy and slow speedy that exists in the manmadesystem.
针对现行人工在线校验安全阀存在的校验准确度差、速度慢等问题，研制了自动在线安全阀校验整定系统。
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The Mississippi River system and the Great Lakes are connected only through the man-made Chicago Sanitary and Ship Canal, which leads from Lake Michigan to the Illinois River.
And not just man. The whole Earth was made from dust particles in orbit around the primitive sun, as were all the other solid objects in the solar system.