ABSTRACT As maintenance and operation costs increase with usage over time, equipment is replaced when the value of new equipment is more attractive. Some methods have been developed to solve this problem. In the public transport sector, such problems are frequently analyzed by fleet managers and determined by bus age restriction regulations. We propose an Integer Programming model that integrates both budgetary and environmental constraints (CO2 emissions) which, as far as we know, have not previously been studied in conjunction. The study aims to determine the optimal replacement plan for a fleet of diesel buses of different size, age, maintenance costs and emissions rates, with new (less polluting) diesel buses over a time horizon of 50 years. The results indicate that it is possible to reduce emissions with a low annual budget using an optimal replacement policy.

中文翻译：

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具有预算和环境约束的公交车队更换优化模型

摘要 随着维护和运营成本随着使用时间的推移而增加，当新设备的价值更具吸引力时，就会更换设备。已经开发了一些方法来解决这个问题。在公共交通部门，此类问题经常由车队经理分析，并由公交车年龄限制规定确定。我们提出了一个整数规划模型，该模型整合了预算和环境约束（CO2 排放），据我们所知，之前还没有将其结合研究。该研究旨在为不同规模、车龄、维护成本和排放率的柴油巴士车队确定最佳更换计划，并在 50 年的时间范围内使用新的（污染较少的）柴油巴士。