基于灰色理论的鱼雷装载可靠性分析

为解决在鱼雷装载可靠度试验数据较少的情况下进行装载可靠性分析困难的问题,利用灰色系统理论及 GM(1,2)建模的思想,研究了鱼雷装载可靠度和工作可靠度之间的灰色关系,基于灰色系统理论建立了两者之间关系的数学模型.计算实例表明,该方法简单实用,可在鱼雷装载可靠度数据样本量较少的情况下对鱼雷装戢可靠度进行有效预测,为鱼雷装载可靠度的评定提供了理论参考.     

综合保障理论之海军航空装备保障发展

现役的航空装备大部分以可靠性为中心来开展设计和维修保障工作，普遍存在装备可用性低、装备预防性维修周期不合理、装备保障成本高等问题，影响了装备保障效能的提升。针对该问题，论文梳理了综合保障理论产生和发展的意义，分析了当前海军航空装备综合保障的现状，针对性提出了几点发展建议和措施，对于开展综合保障工作有积极的推动意义，对现役装备的预防性维修周期规划、可靠性增长、可用性提高、降低保障成本有重要意义。     

Balancing a one‐way corridor capacity and safety‐oriented reliability: A stochastic optimization approach for metro train timetabling

In urban rail transit systems of large cities, the headway and following distance of successive trains have been compressed as much as possible to enhance the corridor capacity to satisfy extremely high passenger demand during peak hours. To prevent train collisions and ensure the safety of trains, a safe following distance of trains must be maintained. However, this requirement is subject to a series of complex factors, such as the uncertain train braking performance, train communication delay, and driver reaction time. In this paper, we propose a unified mathematical framework to analyze the safety‐oriented reliability of metro train timetables with different corridor capacities, that is, the train traffic density, and determine the most reliable train timetable for metro lines in an uncertain environment. By employing a space‐time network representation in the formulations, the reliability‐based train timetabling problem is formulated as a nonlinear stochastic programming model, in which we use 0‐1 variables to denote the time‐dependent velocity and position of all involved trains. Several reformulation techniques are developed to obtain an equivalent mixed integer programming model with quadratic constraints (MIQCP) that can be solved to optimality by some commercial solvers. To improve the computational efficiency of the MIQCP model, we develop a dual decomposition solution framework that decomposes the primal problem into several sets of subproblems by dualizing the coupling constraints across different samples. An exact dynamic programming combined with search space reduction strategies is also developed to solve the exact optimal solutions of these subproblems. Two sets of numerical experiments, which involve a relatively small‐scale case and a real‐world instance based on the operation data of the Beijing subway Changping Line are implemented to verify the effectiveness of the proposed approaches.