An apparatus for computing a coupling noise voltage occurring in a plurality of cells arranged on a plurality of word lines and a plurality of bit lines in a flash memory device includes: a coupling ratio computing unit and a coupling voltage computing unit. The weft thread in the reversal points in an edge portion is folded back forming a loop, and a catch thread which is fed through the loops of the weft thread. When used as a wound dressing, the conductive material is placed in contact with tissue around the periphery of the wound and with the wound, lowering the electrical potential and resistance of the wound and increasing the wound current.