The present invention relates to a polygonal rib structure having {HEAD ~ ribs} directed orthogonal to {TAIL ~ one plane} and intersecting each other to form polygonal shapes 
directed orthogonal to
The present invention relates to a polygonal rib structure having { HEAD ~ ribs } directed orthogonal to { TAIL ~ one plane } and intersecting each other to form polygonal shapes
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH