一种RetinaNet与SE融合的航空取证目标检测算法

针对在开展航空侦察取证时缺乏自动化、智能化取证手段的情况,提出了一种基于Reti-naNet与SE融合的航空取证目标检测算法,解决目标尺度变化大、数据集中类别不均衡的问题,并通过SE (squeeze-excitations)模块引入注意力机制进一步改进性能.该改进算法中的特征金字塔网络FPN可有效应对目标尺寸变化较大...     

基于双重酉滤波的再入目标实时跟踪

适当的运动模型和估计方法是提高再入目标跟踪性能的关键.选择机动再入动力学模型,将再入目标跟踪问题转化为状态和参数的联合估计问题,并利用试验数据分析了再入模型状态和参数的相关性.针对原始双重酉滤波算法的确定性系统输入假设造成信息损失的局限性,提出了一种基于随机性系统输入假设的改进双重酉滤波算法,并从理论上分析了该算法的估...     

Periodic review inventory management with contingent use of two freight modes with fixed costs

We study a stochastic inventory model of a firm that periodically orders a product from a make‐to‐order manufacturer. Orders can be shipped by a combination of two freight modes that differ in lead‐times and costs, although orders are not allowed to cross. Placing an order as well as each use of each freight mode has a fixed and a quantity proportional cost. The decision of how to allocate units between the two freight modes utilizes information about demand during the completion of manufacturing. We derive the optimal freight mode allocation policy, and show that the optimal policy for placing orders is not an (s,S) policy in general. We provide tight bounds for the optimal policy that can be calculated by solving single period problems. Our analysis enables insights into the structure of the optimal policy specifying the conditions under which it simplifies to an (s,S) policy. We characterize the best (s,S) policy for our model, and through extensive numerical investigation show that its performance is comparable with the optimal policy in most cases. Our numerical study also sheds light on the benefits of the dual freight model over the single freight models. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

基于层次分析法的桂西北古村寨火灾风险评估研究

应用层次分析法,根据桂西北古村寨的实际情况,建立了桂西北古村寨的火灾风险评估体系。采用专家打分法获取数据,并应用统计学中的众值原理,对获得的数据进行了统计,得到了指标的权重,建立了适用于实际情况的消防安全检查表。并应用实例证明了这种评估方法行之有效。     

灭火初战应把握的关键环节

灭火作战初战是整个灭火战斗的前期战,它的成功与否直接影响到整个灭火战斗的成败。重点论述了如何把握初战的火情侦查、火场救人、控制火势等三个关键环节,以期对基层广大指战员有所指导。     

基于聚类算法的多无人机系统任务分配

针对现有任务分配方法在任务点较多时不易解算,且计算量大的问题,提出了基于模糊C-均值聚类算法的多无人机系统任务分配方法.首先,利用模糊C-均值聚类算法得到的隶属度矩阵对任务点进行初始分配;其次,针对基于空间划分聚类可能造成各UAV任务不均衡的问题,设计任务的局部优化调整规则;最后,结合单旅行商问题,利用Tabu Sea...     

Quantifying the performance effects of idle time utilization in multiserver systems

In many practical multiserver queueing systems, servers not only serve randomly arriving customers but also work on the secondary jobs with infinite backlog during their idle time. In this paper, we propose a c‐server model with a two‐threshold policy, denoted by (e d), to evaluate the performance of this class of systems. With such a policy, when the number of idle servers has reached d (<c), then e (<d) idle agents will process secondary jobs. These e servers keep working on the secondary jobs until they find waiting customers exist in the system at a secondary job completion instant. Using the matrix analytic method, we obtain the stationary performance measures for evaluating different (e, d) policies. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007.     

遗传算法在防空导弹火力优化分配中的应用

介绍了遗传算法的基本原理、算法设计并结合遗传算法主要解决了如何把目标分配给火力单元的问题,编写了相应的程序,并给出了一个基于遗传算法的火力优化分配方案。     

始终处于大气层内飞行的TBM被动段弹道预测

对大气层内飞行的TBM弹道进行预测时,需要根据不同的应用要求,在求解精度允许范围内用近似方法对六自由度运动进行简化,获得简便实用的弹道预测方法。在假设获得TBM被动段弹道初始位置和速度参数的基础上,首先构建简便实用的处于大气层内飞行的TBM被动段抛物线弹道模型;然后将雷达测得的TBM被动段弹道初始位置和速度参数作为初始条件,对弹道方程采用精度较高的龙格-库塔法进行求解,相应得出被动段弹道上各点及落点的位置和速度参数,进一步确定出落点位置的地理位置经纬度。在某地空攻防对抗仿真项目中应用表明,弹道模型及其求解方法可应用于实战或较为逼真的仿真系统中。     

防空武器系统总体效能的灰色层次评价模型

以某型防空导弹为例,首先建立防空武器系统总体效能评价指标,并采用效用函数法进行指标量化。在此基础上,采用AHP法和Dephi法确定权重系数,采用灰色方法计算综合评估值,从而建立一种综合灰色系统理论、AHP法和ADC法三者优点的灰色层次评价模型。最后对该型防空导弹进行仿真分析。结果证明,灰色层次评价法较AHP法和ADC法具有更大的合理性。