Before revision:  The novel concepts of the direct, indirect and total transactions between any two sectors are introduced, and the corresponding requirements matrices  are systematically formulated relative to both final demands and gross outputs , based on the system decomposition theory  .
After revision:  The novel concepts of the direct, indirect and total transactions between any two sectors are introduced, and the corresponding requirements matrices are systematically formulated relative to both final demands and gross outputs based on the system decomposition theory .