A nitride-based semiconductor device including a substrate; a GaN-containing layer on the substrate; a nitride-containing layer on the GaN layer; a channel blocking layer on the nitride-containing layer, the channel blocking layer including a nitride-based semiconductor; a gate insulation layer on the channel blocking layer; and a gate electrode on the gate insulation layer. The pressure waves alter the surface tensile stresses in the treated metal by reducing the tensile stresses or forming surface compressive stresses. The male end includes a coupling feature. A sample despreader reconstructs the transmitted binary orthogonal symbols by despreading the first state signal obtained from the sample spreader according to a locally generated second subsequence to detect the first main sequence state sample. The digitized image may be taken by a video camera and color quantified to reduce the amount of computing power required before clusters of pixels with similar color classifications are determined and shapes identified. Said lug and groove configured portion of said sidewall is of a rubber composition comprised of a blend of cis 1,4-polyisoprene natural rubber and cis 1,4-polybutadiene rubber which contains reinforcement as carbon black, starchplasticizer composite and aggregates of participated silica together with a coupling agent.