Abstract Project scheduling in manufacturing environments often requires flexibility in terms of the selection and the exact length of alternative production activities. Moreover, the simultaneous scheduling of multiple lots is mandatory in many production planning applications. To meet these requirements, a new resource-constrained project scheduling problem (RCPSP) is introduced where both decisions (activity flexibility and time flexibility) are integrated. Besides the minimization of makespan, two new alternative objectives are presented: maximization of balanced length of selected activities (time balance) and maximization of balanced resource utilization (resource balance). New mixed integer and constraint programming (CP) models are proposed for the developed integrated flexible project scheduling problem. Benchmark instances on an already existing flexible RCPSP and the newly developed problem are solved to optimality. The real-world applicability of the suggested CP models is shown by additionally solving a large industry case.

中文翻译：

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具有活动和时间灵活性的资源受限的多项目调度

摘要 制造环境中的项目调度通常需要在选择和替代生产活动的确切长度方面具有灵活性。此外，在许多生产计划应用程序中，多个批次的同时调度是强制性的。为了满足这些要求，引入了一个新的资源受限项目调度问题 (RCPSP)，其中集成了两个决策（活动灵活性和时间灵活性）。除了最小化完工时间，还提出了两个新的替代目标：最大化所选活动的平衡长度（时间平衡）和最大化平衡资源利用（资源平衡）。针对已开发的集成灵活项目调度问题，提出了新的混合整数和约束规划 (CP) 模型。已经存在的灵活 RCPSP 上的基准实例和新开发的问题都得到了最优解决。所建议的 CP 模型在现实世界中的适用性通过另外解决一个大型行业案例来展示。