In accordance with the prop tree diagram theory, adding the marking stations, the path-marking model in accurate way changes he annular structure speedway network into the tree structure.

准确路径识别模型是指依据图的支撑树理论，添加标识站，把环形路网结构变为树状结构的模型。

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The path leads past a dry-stone wall, marking the boundary of a nature reservation.

BBC: The perfect trip: Switzerland

Six of the recycled stone pillars marking the main paths up the mountain - Llanberis Path, Rhyd-Ddu Path, Snowdon Ranger Path, Miners Track and the Pyg Track - are being erected over the next few weeks.

BBC: Snowdon: Pillars to guide walkers on paths