Figure : Optimal placements for four and eight sensors as determined by the PORSS algorithm. The top row shows the optimal sensor placements across the entire site, and the bottom row shows the optimal sensor placements constrained along the fenceline of the site. Gray dots indicate possible sensor locations, while blue stars represent potential emission source locations, with their heights indicated by the adjacent numbers. Red dots denote the sensors selected by the algorithm, with their corresponding heights also indicated by the adjacent numbers. The optimal placement of four sensors across the site and along the fenceline achieves detection coverage of 52% and 47%, respectively. The optimal placement of eight sensors across the site and along the fenceline achieves detection coverage of 75% and 70%, respectively.