| 摘要 |
The device (3) has a laminar part provided between planks (2) and a substructure (1), and an extension (3.2) provided in a gap between the adjacent planks. The width of the normal projection of the part of the extension on the level of the sub-structure with change of a direction, varies between a smaller minimum value and a larger maximum value. The extension is present between the neighboring planks, and the width is measured within the plane in the direction. A cross-section area of the extension is constant over a subrange of its height. |
