This paper deals with resource unconstrained project scheduling problems with the objective of maximizing the net present value (NPV) of project cash flows. Here we present a heuristic algorithm named as differential procedure (Dif_AOA).&#10In order to evaluate the efficiency of this algorithm, networks with node numbers between 10-1000 and network complexity coefficients between 1.3-6.6 have ...

The minimization of makespan in open shop with time lags has been to be shown NP-hard the strong sense even for case two machines and unit-time operations. total completion time, however, remained that though it weighted or jobs release dates. This note shows operations is which answers long standing question.