Abstract Construction projects usually get delayed for several time periods. When the planning horizon of a project is extended, projections for purchase and salvage of machinery within the planning horizon become inaccurate and less beneficial and often lead to unexpected costs. In this article, we formulate a parallel machine replacement (PMR) problem as a two-stage stochastic program with an uncertain planning horizon. We consider renting as an alternative to purchasing and maintaining the machinery. We show the application of the model through a case study in construction projects. Through numerical analysis, we derive managerial implications and show the value of the stochastic model.

中文翻译：

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地平线不确定下的并行机更换

摘要 建设项目通常会延迟几个时间段。当项目的计划期限延长时，计划期限内对机器的购买和回收的预测变得不准确且效益降低，并且经常导致意外成本。在本文中，我们将并行机器替换 (PMR) 问题表述为具有不确定规划范围的两阶段随机程序。我们考虑将租赁作为购买和维护机器的替代方案。我们通过建筑项目中的案例研究展示了该模型的应用。通过数值分析，我们推导出管理含义并展示随机模型的价值。