We consider life extension models for critical, complex systems with relatively long lifecycles. In contrast to traditional optimal preventive maintenance that usually minimizes the corresponding long run cost rate, a finite number of preventive maintenances are performed to increase the expected lifetime of these systems in an optimal way. The cases of periodic and aperiodic preventive maintenance actions are discussed. The proposed novel approach to life extension allows for simple sensitivity analysis with respect to parameters of the model. The obtained optimal solutions can result in a noticeable increase in the useful life of complex systems. Our findings are illustrated by numerical examples.

我们考虑生命周期相对较长的关键，复杂系统的寿命延长模型。与通常使相应的长期运行成本率最小化的传统的最佳预防性维护相反，执行有限数量的预防性维护以最佳方式增加这些系统的预期寿命。讨论了定期和非定期预防性维护措施的情况。所提出的延长寿命的新颖方法允许针对模型的参数进行简单的敏感性分析。获得的最佳解决方案可以显着增加复杂系统的使用寿命。数值示例说明了我们的发现。