Communications to the Editor--A Note on "Decomposition of Project Networks"

In their paper Management Science, Vol. 11, No. 3, January 1965, pp. 444-459), S. C. Parikh and W. S. Jewell discuss the decomposition of cost-time project networks into subnetworks to aid in finding a cost function for the entire project. They suggest that each subproject be replaced by a set of fictitious activities (in series or in parallel) and that a subsequent analysis be performed using network flow theory. However, when the network configuration is such that series and parallel subprojects can be successively joined to give one project, a simpler method is available, which we wish to present here.