Each gas line shall be clearly labeled (colour and written code) for every 1.5-meter distance. Labeling shall also indicate the direction of gas flow.

气体管路每隔1.5米的距离，都要有明确标示，同时指示气体的流向。

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Results show that the gas flow velocity along the thickness direction is regularly distributed in a parabolic curve and the maximum velocity is in the center of the slot.

结果表明，其速度沿狭缝厚度方向按抛物线规律分布，狭缝中心速度最高，流动状态一般为层流；

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According to geologic model of unsteady groundwater flow in heterogeneous medium and adopting the finite difference solution, the direction and strength of oil gas migration can be quantified.

根据非均匀各向异性地层的非稳定的地下水流动模型，采用有限差分法求解，可以定量判断油气运移的方向及强度。

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