Application of Markov renewal theory and semi-Markov decision processes in maintenance modeling and optimization of multi-unit systems

In this paper, a condition-based maintenance model for a multi-unit production system is proposed and analyzed using Markov renewal theory. The units of the system are subject to gradual deterioration, and the gradual deterioration process of each unit is described by a three-state continuous time homogeneous Markov chain with two working states and a failure state. The production rate of the system is influenced by the deterioration process and the demand is constant. The states of the units are observable through regular inspections and the decision to perform maintenance depends on the number of units in each state. The objective is to obtain the steady-state characteristics and the formula for the long-run average cost for the controlled system. The optimal policy is obtained using a dynamic programming algorithm. The result is validated using a semi-Markov decision process formulation and the policy iteration algorithm. Moreover, an analytical expression is obtained for the calculation of the mean time to initiate maintenance using the first passage time theory.     

基于排队论的反舰导弹突防概率研究

根据水面舰艇对海导弹攻击中作战指挥的需要,提出了基于排队论中随机服务理论的反舰导弹突防概率解算模型.综合研究了目标舰艇编队采用各种手段进行抗击帮助条件下,反舰导弹突防概率的计算问题,并且结合想定装备参数进行了算例分析.为指挥员实施导弹攻击提供辅助决策和量化支持.     

基于前景理论的CGF Agent决策建模研究

前景理论(Prospect Theory,PT)描述了个体在不确定条件下的决策规律,较好地刻画了决策者的风险偏好。分析表明,PT在作战决策建模中具有一定的适用性和可行性。提出了一种基于PT的计算机生成兵力(Computer Generated Forces,CGF)Agent决策建模方法,给出了CGF Agent的建模框架,对CGF Agent决策过程中方案选择的具体步骤和算法进行了详细阐述。实验表明,所提出的方法在一定程度上提高了CGF Agent决策行为的真实性,证明了所提出方法的有效性。     

人本主义教育思想的德育解读与借鉴

人本主义教育思想在教育理念、教育目标、教育过程、教育方法、教育评价等方面均对德育具有借鉴意义。德育的目标指向：培育受教育者的完美人性;实施途径：强调受教育者的直接经验;德育模式：凸显受教育者的主体地位。     

基于博弈论的装备科研、购置、维修经费比例关系优化分析

通过不同时期国家战略部署、科研发展情况及经济承受能力对装备经费分配的影响分析,采用博弈的方法,建立了装备科研、购置和维修费之间的比例关系优化模型,给出了寻求纳什均衡点的迭代算法,并进行了仿真计算.仿真结果证明了该方法的可行性与正确性.     

Empirical Biases and Some Remedies in Estimating the Effects of Selective Reenlistment Bonuses on Reenlistment Rates

Researchers have, for decades, been attempting to estimate the effects of Selective Reenlistment Bonuses (SRBs) on the probability of reenlistment for the military services. SRBs are targeted to specific military occupations for which reenlistment rates are lower (or expected to be lower) than what is needed. This article first identifies four primary sources of biases affecting these models: reverse causality from supply shifts (a negative bias), the endogeneity of the decision point causing coded SRBs to be higher for reenlisters than leavers (a positive bias), measurement error (a likely negative bias), and excess supply preventing the full effect of an SRB change to materialize (a positive or negative bias). The report proceeds to develop a model that attempts to address the first two biases. With U.S. Navy data from FY2001-FY2008, I examine the extent to which these two biases are affecting the estimated SRB effects. Despite these corrections, the difficulty of addressing the other biases calls into doubt studies that examine the effects of retention bonuses or even the effects of the structure of military pay in general.     

基于灰色系统理论的火灾事故预测方法

简要叙述应用灰色系统理论进行火灾事故预测的理论和方法 ,建立了火灾事故预测的GM (1,1)模型 ,并用该模型对火灾事故进行预测。     

微分对策界栅理论在舰艇作战能力评估中的应用

作战能力是表征战斗舰艇战术技术性能的一项重要指标,如何正确评价舰艇的作战能力一直是军事运筹研究的热点.利用定性微分对策的界栅理论研究了一类作战问题,通过构造捕获区面积和咽喉区域面积,并以此作为动态评估舰艇作战能力的衡量指标.研究结果可为综合评价舰艇作战能力提供一条新途径.     

横向效应增强型弹垂直侵彻薄靶的轴向剩余速度理论分析

为了得到横向效应增强型弹（Penetration with Enhanced Lateral Efficiency projectile, PELE）对金属薄靶垂直侵彻后的弹体轴向剩余速度，运用平面冲击波理论，对PELE的侵彻机理进行分析。参照平头弹体对靶板的侵彻模型，将PELE侵彻过程中的能量损失划分为以下几个部分：外壳体和内芯撞靶区域对应的环形塞块获得的能量、冲击波作用下弹体的内能增量以及剪切耗能等。然后根据能量守恒原理，得到PELE垂直侵彻金属薄靶后的PELE弹体轴向剩余速度的理论模型。为了验证该模型的合理性和准确性，设计相应的试验进行验证。结果表明，不同条件下得到的试验结果和理论模型得到的计算结果均吻合得较好。因此，得到的PELE垂直侵彻薄靶的轴向剩余速度理论模型可为工程应用提供指导和参考。     

内置频率对Duffing振子微弱二进制相移键控信号盲检测影响

采用Duffing振子实现对微弱二进制相移键控（Binary Phase Shift Keying, BPSK）信号的盲检测时，Duffing系统输出的周期态和混沌态转换之间存在过渡带。针对这一问题，推导出过渡带时长和Duffing系统内置频率之间的关系表达式；指出内置频率越高，过渡带时间越短；仿真实验给出时间频率响应曲线。内置频率的提高，会降低系统检测微弱信号的灵敏度。针对这一问题，推导出周期态下Duffing系统输出幅度作为因变量、内置频率作为自变量的表达式；仿真实验给出幅频响应曲线。针对微弱BPSK信号盲检测，建立变尺度方法和检测阵列相结合的基于S变换提取Duffing系统输出幅度包络的微弱BPSK信号盲检测模型，仿真实验验证了模型方法的有效性。