A multi‐stage stochastic programming approach for network capacity expansion with multiple sources of capacity

In networks, there are often more than one sources of capacity. The capacities can be permanently or temporarily owned by the decision maker. Depending on the nature of sources, we identify the permanent capacity, spot market capacity, and contract capacity. We use a scenario tree to model the uncertainty, and build a multi‐stage stochastic integer program that can incorporate multiple sources and multiple types of capacities in a general network. We propose two solution methodologies for the problem. Firstly, we design an asymptotically convergent approximation algorithm. Secondly, we design a cutting plane algorithm based on Benders decomposition to find tight bounds for the problem. The numerical experiments show superb performance of the proposed algorithms compared with commercial software. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 600–614, 2017     

GPS时分二进制偏移载波调制信号的高精度无偏抗多径算法

二进制偏移载波调制信号将在卫星导航系统中得到广泛应用。全球定位系统的L1C信号导频分量采用了时分二进制偏移载波调制,对此信号直接采用码参考波形算法消除多径时的鉴别曲线收敛点存在偏差,从而影响测距偏差。因此,提出一种时分二进制偏移载波调制信号的高精度无偏抗多径算法。通过时分的方式分别生成针对BOC(1,1)和BOC(6,1)分量的本地闸波,以保证鉴相函数在码相位无偏差时等于0。由于更好地利用了BOC(6,1)信号分量,该技术在实现无偏跟踪的同时,还能提高跟踪精度。     

磁探针位置及角度偏移对电磁发射过程测试的影响

简化电磁发射装置中的导轨和电枢为线电流下的直导体,建立发射装置的物理模型。利用毕奥-萨伐尔定律和感应电动势原理,推导出磁探针线圈中心放置点的磁感强度。假设线圈范围内的磁场为均匀磁场,计算得到磁探针线圈产生的电动势。以此设计测量所用的磁探针,并和测试数据对比验证模型的正确性。在多次试验中发现,发射过程中装置振动导致磁探针距离变化和角度偏转问题。测量并分析三组单次发射中的故障测试状态。仿真和实验数据表明:小范围距离变化没有使磁探针的测试性能失效,但角度偏移对下一步的速度拟合带来误差干扰,且随着角度增大拟合速度逐步减小。     

适用于认知无线传感器网络的高效频谱分配方法

广泛工作在ISM(Industrial,Scientific and Medical)频段的无线传感器网络面临严重的频谱稀缺问题。在无线通信中,动态频谱分配被认为是提高频谱效能的重要途径。针对典型集中式管理的认知无线传感器网络设计了基于图着色结合负载强度的高效频谱分配算法。首先在协议干扰模型下确保频谱资源在空间上充分利用,随后综合考虑节点负载强度与公平性建立优化模型并按照乘子法加拟牛顿法框架求解最优值。仿真实验表明算法与固定频谱分配方式和传统自适应频谱分配算法相比,在系统吞吐量和节点缓冲区队列长度两个关键性能指标上具有显著优势。     

合成分队双层主从决策模型研究

针对合成分队不同指挥层级之间的决策交互优化问题,提出了基于主从决策的双层武器目标分配模型。该模型能够体现上下指挥层级之间交互式决策协调优化的特点:上层目标为主攻方向我方遭受威胁最小,下层目标为对敌打击最大。结合合成分队作战决策的特点和要求,提出了一种求解该模型的改进型粒子群优化算法。仿真结果表明,该模型合理有效,改进的求解算法能够获得满意解。     

基于双层规划的通信干扰兵力部署优化

投掷式通信干扰机是未来通信对抗装备发展的一种趋势,针对其压制无线战术通信的兵力部署优化问题,引入"通信干扰压制概率"和"通信干扰效益"两个指标,建立了基于双层规划的兵力部署优化模型,上层规划以整体通信干扰效益最大化为目标,下层为随机机会约束规划,以通信干扰压制概率满足一定置信水平为约束,以干扰机需求量最小化为目标。采用随机模拟、遗传算法和动态规划相结合的混合智能算法求解双层规划模型,并通过算例分析验证了模型的有效性。     

带优先级的单类型航空弹药转运多目标规划模型

针对航母航空弹药转运过程非常复杂、涉及设备多、要求高的特点,在对其流程进行细致分析的基础上,将其抽象为一个两阶段多目标规划问题。同时,深入分析了转运过程中的各种约束条件、构建了该问题的两阶段优化模型。建模时,不仅考虑了武器升降机的有效利用、弹药量的合理分配等因素,还考虑了转运时对于不同类型弹药转运优先级与停机区弹药需求优先级的要求。通过模型优化,在满足转运优先级要求的基础上,能有效提高航空弹药的转运效率。     

基于多Agent无人机协同侦察任务规划模型

建立了多无人机协同侦察任务规划模型,在考虑侦察时间间隔约束和目标载荷需求基础上,给出了位于不同基地的无人机优化部署和调度策略,并提出了基于多Agent的优化搜索仿真算法,利用Matlab实现了无人机优化配置和任务规划模型,得出了无人机优化配置和任务规划方案,最后分析了模型算法存在的某些不足,提出了模型改进的方向。     

The building evacuation problem with shared information

In this article, the Building Evacuation Problem with Shared Information (BEPSI) is formulated as a mixed integer linear program, where the objective is to determine the set of routes along which to send evacuees (supply) from multiple locations throughout a building (sources) to the exits (sinks) such that the total time until all evacuees reach the exits is minimized. The formulation explicitly incorporates the constraints of shared information in providing online instructions to evacuees, ensuring that evacuees departing from an intermediate or source location at a mutual point in time receive common instructions. Arc travel time and capacity, as well as supply at the nodes, are permitted to vary with time and capacity is assumed to be recaptured over time. The BEPSI is shown to be NP‐hard. An exact technique based on Benders decomposition is proposed for its solution. Computational results from numerical experiments on a real‐world network representing a four‐story building are given. Results of experiments employing Benders cuts generated in solving a given problem instance as initial cuts in addressing an updated problem instance are also provided. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008