An incremental approach for temporal analysis in networks with imprecise activity and time lag durations

This paper proposes algorithms for computing the possible values of the latest starting times and maximal floats in a network with imprecise activity and time lag durations, represented by means of interval or fuzzy numbers. Although these problems have been solved when the activity durations are imprecise, we propose polynomial algorithms which can handle the imprecision in time lags of the precedence relations and are simpler than the previously algorithms. Inserting the imprecise time lags in the network leads the proposed algorithms to be more practical. After positioning this paper in the scope of project scheduling under uncertainty, the algorithms for computing of the interval value of latest starting times and maximal floats of activities in networks with interval activity and time lag durations are proposed. Then, the interval activity and time lag durations are generalized into fuzzy numbers.