Abstract: It is of the type comprising a corrugated and sealed internal metal tube (1), a pressure vault (2) wound at a short pitch and having an internal surface which faces the corrugations of the corrugated internal tube, an intermediate sheath, at least two groups of inner and outer armoring layers (3, 5), the armoring layers being wound at a lay angle of less than 55.degree., and an outer-sheath (6), and it is characterized in that the intermediate sheath (4) is sealed and is arranged between the two groups of armoring layers (3, 5), the said inner group of armoring layers (3) bearing directly on the pressure vault (2).

Abstract: The invention concerns a flexible conduit comprising an internal gasproof undulating metal tube (1), the wall of which has helical undulations (8), the external surface of said internal tube having at least concave (10) and convex (11) rounded parts corresponding to the internal and external parts of the undulations respectively, and at least an arch (2) arranged around said internal metal tube and made up of at least a form wire (9) coiled in spires. The invention is characterized in that the arch (2) has an internal surface with helical undulation, comprising at least concave (16) and convex (15) rounded parts and the external surface of the internal metal tube is supported in its concave rounded part (10) by a convex part (15) of the arch (2) internal surface and in its convex rounded part (11) by a concave part (16) of the arch internal surface, said internal arch surface and said internal tube external surface matching in form and the interstices (i) between the adjacent spires are small.

Abstract: The present invention discloses a method and apparatus for testing a memory array. The memory array includes a plurality of memory blocks. A test data item is written to the memory blocks at a pre-determined location in parallel. The data from the memory blocks are read at the pre-determined location in parallel. These data items are compared to determine if they are identical. One of these data items is compared with the test data item.