Systems and methods that provide a barrier for protection of active layers associated with a vertical multi junction photovoltaic cell. When performing a page program operation with a selected memory device, a memory controller loads the data into the page buffer of one selected memory device and also into the page buffer of another selected memory device in order to store a back-up copy of the data. The method provided by the embodiments of the present invention objectively reflects a current channel quality status, so that the base station can acquire accurate channel quality information, thereby objectively scheduling data based on the channel quality information and improving data sending efficiency of a channel. The pluralities of protuberances form converging and diverging optical shapes for mixing different wavelengths scattering from the optical surface. A second transceiver transmits at the second bandwidth and receives at the first bandwidth. This method is applicable to any composite structures, but is particularly valuable for light weight composite aircraft wing-to-fuselage connections.