一种用于战术通信网络仿真的通信业务量模型

针对战术通信网络仿真的实际需求,在分析现有通信业务量建模方法基础上,基于吸引系数法和泊松流模型,提出了一种用于战术通信网络仿真的通信业务量建模方法。该方法依据泊松流模型构建了指挥机构生成通信业务总量模型,根据指挥机构两两之间通信业务量大小关系建立了吸引系数矩阵,依据吸引系数占比将指挥机构生成通信业务总量分配至接收用户,最后引入了不同作战阶段通信业务量强度繁忙系数。仿真结果表明,该方法能够快速有效生成指挥机构通信业务量,较好满足战术通信网络仿真需求。     

延时下基于事件触发的多智能体系统一致性

研究了通信延时下基于事件触发的一阶多智能体系统一致性问题。针对有向固定拓扑,设计了通信延时下基于事件触发机制的控制器。利用李雅普诺夫稳定性理论提出了能够使系统稳定和一致的事件触发函数和时延上界,并利用该事件触发规则求取两次触发之间的最小间隔,证明了该系统不存在Zeno行为。事件触发机制的引入有效减少了控制器的更新次数和智能体之间的通信频率,节约了资源,最后通过仿真实例验证了该理论方法的可行性与有效性。     

作战运筹实验基本问题探讨

从军事运筹学研究的发展需求出发,阐述了模拟、实验与运筹之间的关系,分析了作战运筹的实验基础,引出了作战运筹实验的基本概念及其设计理论、方法、过程,并根据综合集成理论提出了综合集成模式下的作战运筹实验框架,最后对作战运筹实验的发展提出了一些建议.     

Approximation results for min‐max path cover problems in vehicle routing

This article studies a min‐max path cover problem, which is to determine a set of paths for k capacitated vehicles to service all the customers in a given weighted graph so that the largest path cost is minimized. The problem has wide applications in vehicle routing, especially when the minimization of the latest service completion time is a critical performance measure. We have analyzed four typical variants of this problem, where the vehicles have either unlimited or limited capacities, and they start from either a given depot or any depot of a given depot set. We have developed approximation algorithms for these four variants, which achieve approximation ratios of max{3 ‐ 2/k,2}, 5, max{5 ‐ 2/k,4}, and 7, respectively. We have also analyzed the approximation hardness of these variants by showing that, unless P = NP , it is impossible for them to achieve approximation ratios less than 4/3, 3/2, 3/2, and 2, respectively. We have further extended the techniques and results developed for this problem to other min‐max vehicle routing problems.© 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

便携式绳轨提升装置的轮盘-绳索摩擦提升力模型

为提高便携式绳轨提升装置的实用性,对基于摩擦的该类装置的提升能力展开研究。利用控制变量法分别研究末端拉力、包角与轮盘-绳索相对尺寸对两者之间摩擦提升力的影响,结果表明该提升力均随三种因素的增加而增加但趋势变缓;轮盘-绳索之间的静摩擦系数随绳索末端拉力与包角的增加而减小并趋于稳定,随轮盘-绳索相对尺寸的增加而增加并收敛。论证了包角与末端拉力对摩擦提升力的影响相互等效,发现了轮盘-绳索摩擦的尺寸效应,构建了以上因素共同作用下的轮盘-绳索摩擦提升力模型。该模型是对欧拉公式的扬弃,深化了对轮盘-绳索摩擦规律的认识,对便携式绳轨提升装置的小型化、轻量化设计具有重要意义。     

掠飞末敏弹耦合运动动导数计算

以新型掠飞末敏弹为研究对象,提出了基于欧拉转动定理和滑移网格技术的复杂角运动模拟方法,利用著名的罗德里格斯转换矩阵插值求得弹箭在每个时间步的角速度修正值,并指定给球形滑移网格区。通过对非定常气动参数进行求解辨识,分析了不同马赫数下掠飞末敏弹滚转运动对其俯仰组合动导数和升力系数动导数的影响规律。结果表明:所提角运动模拟方法可有效消除姿态角计算的累积误差,实现对弹箭任意给定角运动的准确模拟;弹箭滚转运动对俯仰组合导数和升力系数动导数的辨识结果均存在显著影响,在进行弹箭动导数计算和稳定性分析时需充分考虑俯仰耦合效应的影响。     

强爆轰驱动超高速碎片发射装置设计因素分析

为了得到发射装置设计因素和超高速碎片性能间的关系,考虑了药型罩的材料、炸药种类、装药长径比、药型罩的锥角、药型罩的厚度、药型罩顶部靠近装药侧的曲率半径等设计因素,采用AUTODYNTM,结合正交试验,对超高速碎片的发射过程进行数值模拟。结果表明,3种发射装置结构分别可以提供质量为1. 533 g的紫铜碎片、速度为11. 649 km/s的铝碎片、动能为85. 6 k J的铝碎片; 2种发射装置结构均可以提供质量大于1 g、速度高于11 km/s的密实结构圆柱状碎片。验证了仿真方法的可信性,对影响碎片性能的设计因素进行了分析、排序,并得到了这些设计因素与碎片质量、速度、动能的关系。     

Nonperiodic preventive maintenance for repairable systems

As a complex system with multiple components usually deteriorates with age, preventive maintenance (PM) is often performed to keep the system functioning in a good state to prolong its effective age. In this study, a nonhomogeneous Poisson process with a power law failure intensity is used to describe the deterioration of a repairable system, and the optimal nonperiodic PM schedule can be determined to minimize the expected total cost per unit time. However, since the determination of such optimal PM policies may involve numerous uncertainties, which typically make the analyses difficult to perform because of the scarcity of data, a Bayesian decision model, which utilizes all available information effectively, is also proposed for determining the optimal PM strategies. A numerical example with a real failure data set is used to illustrate the effectiveness of the proposed approach. The results show that the optimal schedules derived by Bayesian approach are relatively more conservative than that for non‐Bayesian approach because of the uncertainty of the intensity function, and if the intensity function are updated using the collected data set, which indicates more severe deterioration than the prior belief, replacing the entire system instead of frequent PM activities before serious deterioration is suggested. © 2010 Wiley Periodicals, Inc. Naval Research Logistics, 2010     

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。