A memory array includes a sensing circuit for sensing bit line current while keeping the voltage of the selected bit line substantially unchanged. The closure comprises a CD port attached to the bag. The chamber includes means for maintaining the disc media in a stable state within the chamber, including a structure defining support for the disc media such that the disc media is allowed to rotate, while limiting the linear movement of the disc media both perpendicular to and parallel to the plane of the media. In this configuration, the long paper side floats of the base fabric can provide a desirable balance of properties. In addition, this invention also provides photovoltaic cells and a manufacturing method thereof. In the method, LMS is used for estimating the parameters of the RBFNN.