| 摘要 |
The structure (11) has a set of wooden boards (12) regularly spaced with each other and oriented parallel with respect to each other. The boards cooperate with a lower face of sound-absorbing panel so as to define a set of grooves (15) at level of lower side (14). Each of the grooves includes a distal face (16) opposite to a bottom face (17). Sum of areas of the distal faces of the structure is less than one-third of total area of developed surface forming the lower side of the structure. The boards have same thickness (e) and width (l). |
