运用动态规划的智能卫星集群星间通信路由算法

通过建立智能卫星集群网络模型,把智能卫星集群星间通信路由问题转换为时延最短路径问题,进而提出一种求解此问题的智能卫星集群星间通信路由算法.该路由算法采用动态规划策略分阶段规划智能卫星集群两个成员之间的星间通信路由,在每个规划阶段,负责发送数据的智能卫星自主调用一种星间通信路由静态规划算法,以求出其在当前时刻的后继卫星来...     

大型舰船电力系统网络重构研究

大型舰船电力系统的出现使供电方式由原来的辐射状向环形发展,其网络重构是一个崭新的问题.文中给出了大型舰船电力系统的网络拓扑结构并综合考虑了线路容量限制、节点电压约束及供电负荷优先性的重构数学模型,保证了各种情况下最大限度地给负荷供电.将规划遗传算法应用于所建模型的求解,并应用算例验证了此解法的可行性.     

非饱和土与特殊土力学的理论与实践

对非饱和土与特殊土(包括填土、黄土、膨胀土、膨润土等)开展了持久深入的研究,取得了系统的创造性成果:在国内率先研制成非饱和土固结仪、直剪仪、渗气仪、小型三轴仪、温控三轴仪、多功能三轴仪和土工CT-三轴仪等一系列仪器设备,揭示了非饱和土与特殊土的水气运动规律、变形、强度、屈服、水量变化、细观结构演化、温度效应等许多重要力...     

Algorithms for solving the conditional covering problem on paths

Consider the conditional covering problem on an undirected graph, where each node represents a site that must be covered by a facility, and facilities may only be established at these nodes. Each facility can cover all sites that lie within some common covering radius, except the site at which it is located. Although this problem is difficult to solve on general graphs, there exist special structures on which the problem is easily solvable. In this paper, we consider the special case in which the graph is a simple path. For the case in which facility location costs do not vary based on the site, we derive characteristics of the problem that lead to a linear‐time shortest path algorithm for solving the problem. When the facility location costs vary according to the site, we provide a more complex, but still polynomial‐time, dynamic programming algorithm to find the optimal solution. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005.     

On parallel machine replacement problems with general replacement cost functions and stochastic deterioration

The parallel machine replacement problem consists of finding a minimum cost replacement policy for a finite population of economically interdependent machines. In this paper, we formulate a stochastic version of the problem and analyze the structure of optimal policies under general classes of replacement cost functions. We prove that for problems with arbitrary cost functions, there can be optimal policies where a machine is replaced only if all machines in worse states are replaced (Worse Cluster Replacement Rule). We then show that, for problems with replacement cost functions exhibiting nonincreasing marginal costs, there are optimal policies such that, in any stage, machines in the same state are either all kept or all replaced (No‐Splitting Rule). We also present an example that shows that economies of scale in replacement costs do not guarantee optimal policies that satisfy the No‐Splitting Rule. These results lead to the fundamental insight that replacement decisions are driven by marginal costs, and not by economies of scale as suggested in the literature. Finally, we describe how the optimal policy structure, i.e., the No‐Splitting and Worse Cluster Replacement Rules, can be used to reduce the computational effort required to obtain optimal replacement policies. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005     

Optimal power control in a wireless network using a model with stochastic link coefficients

This paper addresses optimal power allocation in a wireless communication network under uncertainty. The paper introduces a framework for optimal transmit power allocation in a wireless network where both the useful and interference coefficients are random. The new approach to power control is based on a stochastic programming formulation with probabilistic SIR constraints. This allows to state the power allocation problem as a convex optimization problem assuming normally or log‐normally distributed communication link coefficients. Numerical examples illustrate the performance of the optimal stochastic power allocation. A distributed algorithm for the decentralized solution of the stochastic power allocation problem is discussed. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2005     

信息不完备群组决策问题的ANP方法

群组决策是一类重要的决策问题,信息不完备的群组决策问题,因为判断矩阵有缺损,传统的AHP不能求解.文中将评价图引入信息不完备的群组决策问题,在此基础上提出用二次规划问题解决在这种情况下的权重确定问题,最后通过ANP的超矩阵得到总排序结果.经过实例检验,证明了ANP方法的正确性与可行性.     

基于二阶锥规划的MIMO雷达稳健自适应波束形成

针对MIMO雷达自适应波束形成中期望目标导向矢量的失配问题,提出了一种基于二阶锥规划(SOCP)的稳健自适应波束形成算法。该算法首先将1个MN维(M,N分别为发射和接收阵元数)的权矢量分解成2个低维(1个M维和1个N维)权矢量的Kronecker积,然后分别限制实际的目标发射导向矢量和目标接收导向矢量与假定的导向矢量之间的误差范数的边界,通过优化最差性能,利用SOCP求得分解后的2个权矢量,最后再合成原权矢量。通过降维处理,算法在保证波束形成器性能的基础上,有效地降低了运算复杂度。仿真结果验证了算法的有效性。     

反导作战管理技术研究

反导作战管理技术是指对反导体系内的传感器和火力资源进行以任务规划为核心的指挥与控制技术,主要包括传感器资源作战管理和火力资源作战管理两大部分。首先对反导作战管理与指挥控制系统的发展情况进行了简要分析,然后针对反导作战管理技术的内涵、主要任务、层次结构进行了系统研究,最后初步探讨了反导作战管理的核心内容和涉及的关键技术。     

Production/distribution system design with inventory considerations

This study addresses the design of a three‐stage production/distribution system where the first stage includes the set of established retailers and the second and third stages include the sets of potential distribution centers (DCs) and potential capacitated suppliers, respectively. In this problem, in addition to the fixed location/operating costs associated with locating DCs and suppliers, we consider the coordinated inventory replenishment decisions at the located DCs and retailers along with the appropriate inventory costs explicitly. In particular, we account for the replenishment and holding costs at the retailers and selected DCs, and the fixed plus distance‐based transportation costs between the selected plants and their assigned DCs, and between the selected DCs and their respective retailers, explicitly. The resulting formulation is a challenging mixed‐integer nonlinear programming model for which we propose efficient heuristic solution approaches. Our computational results demonstrate the performance of the heuristic approaches as well as the value of integrated decision‐making by verifying that significant cost savings are realizable when the inventory decisions and costs are incorporated in the production distribution system design. © 2012 Wiley Periodicals, Inc. Naval Research Logistics 59: 172–195, 2012