| 摘要 |
<p>An apparatus is provided comprising a first tubular having an inside surface and outside surface defining an outside diameter; a second tubular concentric with and said first tubular, said second tubular having an inside surface defining an inside diameter greater than the outside diameter of said first tubular, an outside surface, and a longitudinal axis; a plurality of spacers between said first and second tubulars, each said spacer having a longitudinal axis parallel to the longitudinal axis of said second tubular, wherein at least one said spacer is hollow; and at least one means for sensing data and/or at least one means for collecting data and/or at least one means for transmitting data carried within said at least one hollow spacer.</p> |
