提高大型轴类工件轴径在线测量精度，其主要困难在于用非接触法时如何精确地确定测量点的位置。

The main difficulty for improving the on-line diameter-measuring accuracy of large-sized axis depends on how the measurement position is accurately determined by non-contact methods.

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本文先指出了非接触法测流量的优越性，再基于各种物理原理，叙述了封闭管道流量的几种非接触测量方法与特点。

The advantages. methods and their properties of the non-contact flow measurement for closed pipelines on the basis of some physical principles are described in this paper.

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介绍了滤纸法量测非饱和土吸力的工作原理，以及滤纸接触法量测土体基质吸力和非接触法量测土体总吸力的试验方法和注意事项。

The basic principle, approach and precautions for measuring both the matric and the total suction of unsaturated soils using the filter paper method are introduced.

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