Proactive approach to address the uncertainty in short-term scheduling

The identification of reliable schedules serves a valuable function as a basis for coordinating outside activities within the highly dynamic and uncertain supply chain (SC) environment. A contribution is made in the area of proactive scheduling with the development of a stochastic modeling framework to support the short-term scheduling problem with uncertain operation times and equipment breakdowns. A set of scenarios for the uncertain parameters is anticipated in the decision stage, along with information concerning the reactive scheduling approach to be taken during schedule execution. A robust predictive schedule is pursued, with the flexibility to absorb disruptive events without major changes when rescheduling is required. Either rigorous or heuristic techniques can be used to optimize a robustness measure that explicitly accounts for the eventual wait times and idle times that may arise during execution. The application of the framework to different case studies shows the flexibility of the predictive schedule, the different decisions that can be drawn based on the rescheduling strategy considered, and the importance of exploiting the information of the uncertainty as well as the incorporation of the rescheduling policy proactively. (C) 2007 Elsevier Ltd. All rights reserved.