A roof decking membrane welding system and method comprises first and second roof decking membranes having edge portions thereof welded to each other so as to define a seamed connection therebetween. Gated amperometric pulse sequences including multiple duty cycles of sequential excitations and relaxations may provide a shorter analysis time andor improve the accuracy andor precision of the analysis. A volume multicast layer over RCP provides for multicasting to specified volume extents of the blocks. Thereby, when a plug is inserted in a socket, the cap is positioned stably to enhance using safety and aesthetics appearance.