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161.
Various application domains require the integration of distributed real-time or near-real-time systems with non-real-time systems.Smart cities,smart homes,ambient intelligent systems,or network-centric defense systems are among these application domains.Data Distribution Service(DDS)is a communi-cation mechanism based on Data-Centric Publish-Subscribe(DCPS)model.It is used for distributed systems with real-time operational constraints.Java Message Service(JMS)is a messaging standard for enterprise systems using Service Oriented Architecture(SOA)for non-real-time operations.JMS allows Java programs to exchange messages in a loosely coupled fashion.JMS also supports sending and receiving messages using a messaging queue and a publish-subscribe interface.In this article,we pro-pose an architecture enabling the automated integration of distributed real-time and non-real-time systems.We test our proposed architecture using a distributed Command,Control,Communications,Computers,and Intelligence(C4I)system.The system has DDS-based real-time Combat Management System components deployed to naval warships,and SOA-based non-real-time Command and Control components used at headquarters.The proposed solution enables the exchange of data between these two systems efficiently.We compare the proposed solution with a similar study.Our solution is superior in terms of automation support,ease of implementation,scalability,and performance. 相似文献
162.
进度风险的随机网络建模与仿真分析 总被引:1,自引:0,他引:1
为研究装备研制工程进度的风险分布特征,建立了包含正态分布、β分布、三角分布的随机网络进度风险分析模型,通过蒙特卡罗法仿真获得工程项目的进度估计及其统计分布特性,从而获得工程总工期的风险,并结合实例进行了分析. 相似文献
163.
This paper focuses on certain types of distribution networks in which commodity flows must go through connections that are subject to congestion. Connections serve as transshipment and/or switching points and are modeled as M/G/1 queues. The goal is to select connections, assign flows to the connections, and size their capacities, simultaneously. The capacities are controlled by both the mean and the variability of service time at each connection. We formulate this problem as a mixed integer nonlinear optimization problem for both the fixed and variable service rate cases. For the fixed service rate case, we prove that the objective function is convex and then develop an outer approximation algorithm. For the variable service rate case, both mean and second moment of service time are decision variables. We establish that the utilization rates at the homogeneous connections are identical for an optimal solution. Based on this key finding, we develop a Lagrangian relaxation algorithm. Numerical experiments are conducted to verify the quality of the solution techniques proposed. The essential contribution of this work is the explicit modeling of connection capacity (through the mean and the variability of service time) using a queueing framework. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005. 相似文献
164.
针对某新型弹药弹道性能检测的需要,利用气相色谱法对其发射药中钝感剂含量分布进行了测定,建立了考虑钝感剂含量分布的该新型火炮的内弹道模型。模型中钝感剂对弹道性能的影响是通过对火药燃速和火药力的影响来体现的。应用该模型对2个批次的弹药进行了内弹道计算,并对一定樟脑含量的火药内弹道性能进行了预测。计算结果表明,樟脑含量对最大膛压影响较大,但对初速的影响则不如膛压明显。 相似文献
165.
研究了基于对称Alpha稳定分布的浅海环境下混响及噪声的建模问题.分析了浅海环境下混响形成过程及其非高斯特性,采用对称Alpha稳定分布理论对其进行了建模,并从声呐接收端的混响瞬时值以及包络的概率密度分布与Alpha稳定分布的匹配程度验证了模型的有效性.研究了基于对称Alpha稳定分布模型的混响噪声背景下的目标信号检测方法.提出了三种检测方法并进行了仿真测试,通过检测性能及模型的精确性分析了三种方法的优缺点,验证了建模精度对检测性能的影响. 相似文献
166.
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 相似文献
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为解决炮射悬浮式GPS干扰弹的研制与应用问题,进行了炮射悬浮式GPS干扰弹靶场试验与评估研究,提出了基于雷达、GPS接收机和计算机的靶场试验解决方案和数据处理方法,给出了基于蜂窝结构的干扰弹分布覆盖设计步骤,提出了包括功能性指标、可靠性指标和安全性指标的炮射悬浮式GPS干扰弹评估方法,定义了各评估指标的效益函数。 相似文献
170.
采用贝叶斯方法 ,利用大量的历史数据和工程技术人员的丰富经验确定先验分布 ,制定出验收试验的一种新方案 .按照这一方案 ,在确保产品质量的前提下 ,可大大节省试验时间 ,从而得到十分可观的经济效益 . 相似文献