产品二维不完全预防性维修间隔期优化研究

针对故障受日历时间与使用时间共同影响的二维产品，传统的一维预防性维修已不能满足二维产品的实际需求，鉴于此,提出二维预防性维修概念，以日历时间与使用时间对二维产品进行二维预防性维修决策。建立二维产品故障率函数表达式，对二维预防性维修的过程进行具体的分析，以总期望费用最小为优化目标，建立有限使用期二维不完全预防性维修费用模型。通过实例求出最佳的二维不完全预防性维修间隔期，经对比分析验证了该模型的适用性与有效性，对二维维修策略提出了展望。

Research on Optimization of Two-dimensional Imperfect Preventive Maintenance Intervals of Products

For the products of which the failures are affected by the calendar time and service time, the traditional one-dimensional preventive maintenance can’t meet the actual demand. A concept of two-dimensional preventive maintenance is proposed. The two-dimensional preventive maintenance decision is made according to calendar time and service time. A failure rate function expression of two-dimensional maintenance is established, and the process of two-dimensional imperfect preventive maintenance is analyzed in detail. A cost model of two-dimensional imperfect preventive maintenance is proposed to minimize the consumer’s total expected cost in finite life span. An optimal two-dimensional imperfect preventive maintenance interval is derived through examples, and the the applicability and validity of the proposed model are verified through comparison and analysis. A brief discussion about future research area of two-dimensional maintenance is presented.