Research On Two-Stage Reactive Scheduling Method For Resource-Constrained Project

The traditional resource-constrained project scheduling problem is a deterministic project scheduling problem,with the assumption that the project has complete information and the project execution environment is static.However,this assumption is usually not tenable in reality because all parameters defining a project may change during the process of project implementation.Uncertain factors make it difficult for the schedule based on the deterministic assumption to effectively achieve the established scheduling objectives.Reactive project scheduling refers to the process of modifying or re-optimizing the baseline schedule when it becomes no longer feasible or optimal after the occurrence of disruption events during the process of project implementation.In many cases,in order to avoid risks and improve project performance,ensuring the optimality of the new generated schedule is still a priority for reactive project scheduling.However,there is no research in this field among the existing literature.Reactive project scheduling is an important branch of project scheduling under uncertainty.The existing reactive project scheduling methods ignore the optimal realization of the deterministic project scheduling goal,so they cannot ensure that the reactive schedule is optimal in the new project execution environment.To address this issue,this thesis proposes a resource-constrained multi-mode project reactive scheduling problem with resource availability uncertainties and a resourceconstrained multi-project reactive scheduling problem with new project arrival.Different from the existing reactive project scheduling problems,the reactive project scheduling problems proposed in this thesis first ensure that the new generated schedule is optimal in the new project execution environment,and then minimize the deviation between the old schedule and the new one.In addition,a two-stage reactive project scheduling method based on CPLEX V12.8.0 is proposed.In the first stage,the optimal value of the deterministic project scheduling goal in the new project execution environment can be obtained by fully rescheduling the project.In the second stage,a new optimal schedule achieving the new optimal value of the deterministic project scheduling objective is formulated to minimize the adjustment cost of the baseline schedule.Finally,based on the benchmark instances,the proposed two-stage reactive scheduling method and the existing two methods,including the full rescheduling method,are sufficiently compared and tested.The results demonstrate that the proposed method not only considers the adjustment cost of the baseline schedule,but also optimally achieves the deterministic project scheduling objective,with distinct advantages over the existing methods.This will help to enrich the relevant theories in the field of reactive project scheduling and meet the specific needs of project managers in project management practice.