Flow in Process Models

The edge of the graph from vertex / to vertex 2 indicates a flow of information or perhaps material from vertex 1 to 2 and therefore the element r2l = 1. Similarly, there is a flow directed from vertex 1 to vertex 3 so that r31 = 1 also r43 = 1 and r14 = 1. All other elements of the matrix are 0 since there are no other flows in the graph. The adjacency matrix thus indicates all of the one step paths (flows between two vertices without an intervening vertex) between vertices. If ri = 1, there is a one-step path from vertex./ to vertex Therefore, all of the structure of the graph is contained in the adjacency matrix. 

Boolean multiplication is distributive with respect to Boolean union that is, 

Boolean union, on the other hand, differs significantly from addition. We have, for example, 

Boolean matrix multiplication is carried out according to the usual matrix rules, expressed in terms of the logical product and logical sum as defined above. 

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