ABSTRACT Strategic business plans are based upon assumptions of future wood costs. Future wood costs are affected by future equipment cost inputs and technological change. Equipment replacement decisions react to future cost inputs and technological change, taking advantage of opportunities to reduce future wood costs. By explicitly defining future equipment cost inputs and technological change, and their effect on equipment replacement decisions, future wood costs used in strategic planning have a rational and consistent basis. To ensure consistency between strategic plans and equipment replacement decisions we developed a forward reaching dynamic programming algorithm that recognizes the special structure of the equipment replacement problem. The output is an equipment replacement schedule that can be used to project equipment investment needs, operational costs, and tree harvesting costs. The results show that when we compare the proposed algorithm with the classic infinite series machine replacement approach under constant costs, both of them presented an optimal life with 52 months and a discounted cost of 5.691 USD million. Considering a 1200 month planning horizon under technological changes, the economic life policy proved optimum with 80 months of use for the first machine, while the next generations varied between 69 and 71 months of use with a discounted cost value of 4.617 USD million. Under the estimates of future costs and technological improvements, production costs decline and production rises. The algorithm is intuitive, flexible, easy to calculate, and yields the exact solution. No restrictions are needed on cost inputs over time, technologies, or discount rates.

中文翻译：

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确保战略计划和设备更换决策之间的一致性

摘要 战略业务计划基于对未来木材成本的假设。未来的木材成本受未来设备成本投入和技术变革的影响。设备更换决策对未来的成本投入和技术变革做出反应，利用机会降低未来的木材成本。通过明确定义未来设备成本投入和技术变革，以及它们对设备更换决策的影响，战略规划中使用的未来木材成本具有合理和一致的基础。为了确保战略计划和设备更换决策之间的一致性，我们开发了一种前向动态规划算法，该算法可以识别设备更换问题的特殊结构。输出是设备更换计划，可用于预测设备投资需求，运营成本和树木采伐成本。结果表明，当我们将所提出的算法与恒定成本下的经典无限级数机器更换方法进行比较时，两者都呈现出最佳寿命为 52 个月，折现成本为 5691 美元。考虑到技术变革下 1200 个月的规划期限，第一台机器使用 80 个月的经济寿命政策证明是最佳的，而下一代机器的使用时间在 69 到 71 个月之间，折扣成本值为 461.7 万美元。在未来成本和技术改进的估计下，生产成本下降，产量上升。该算法直观、灵活、易于计算，并产生精确的解。随着时间、技术或贴现率的变化，不需要对成本投入进行限制。