“…As can be seen, the output of the optimization process is a diagonalized matrix with 3 different cells, highlighted with gray color (3 machine groups {(6, 7), (1, 2), (3,4,5)} and 3 families of parts {(4, 5, 8, 10), (1,2,6,9), (3, 7, 11)}). The elements (5,4) and (3,1) are denoted in the MCPF literature as exceptional elements and correspond to entries with a value of 1 outside of the gray diagonal blocks. The elements (4,11) or (6,8) are called voids and correspond to 0s inside the diagonal blocks.…”