GPRS核心网自动拨测系统的设计与实现

GPRS核心网自动拨测系统是在GPRS核心网接口接入,以信令仿真方式向各实体发起拨测业务,从而实现业务可用情况、网元承载信令、路由通畅性、业务感知等指标的周期性自动测试的新一代业务测试系统。该系统具有独创性和前瞻性的特点,填补了国内外相关领域的空白。     

嵌入式工业级无线网关的设计与实现

文中提出了基于嵌入式Linux的异构网络互通互连方案,设计实现了一种基于ARM9平台的嵌入式Linux的无线网关。通过测试验证了以太网LAN和802.11无线网络之间互通和无线网关的可行性。     

基于传递闭包的任务时序依赖关系建模方法

建立正确、有效的任务模型是正确引导出信息系统需求的关键步骤。文中针对任务间时序依赖关系,给出与任务建模相关的若干形式定义和命题,帮助分析人员判断任务间的并发和死锁。给出任务间时序依赖关系建模的详细步骤,并根据时序依赖关系的传递性质,给出一种任务关系图上的传递闭包方法,可以帮助分析人员直观地判断任务间时序依赖关系的问题和错误,科学、合理地标记各个任务的时序等级属性,帮助建模人员从全局上明确各个任务在执行时所处的相对位置,以及在每个阶段需要同时展开哪些任务。     

模糊专家系统自动装弹机故障检测系统

针对步战车装弹机故障检测困难,设计步战车装弹机故障检测系统,自动高效地实现对步战车装弹机的故障检测。利用模糊专家系统解决模糊问题的基本方法,阐述了系统的总体设计和硬件设计,按照输入输出信号的特点,将系统分为模拟信号输入输出模块和数字信号输入输出模块,并详细介绍了系统软件的核心——模糊专家系统的设计,特别是对模糊专家系统中知识库、推理机、解释模块以及学习模块的开发进行了探讨。     

基于“北斗”卫星的四级车辆指挥管理系统研究

结合"北斗"卫星定位系统的原理和特点,提出了一种基于我国自主研制双星定位系统的四级车辆指挥管理系统的设计,并分析了其组成、主要功能和特点,该系统能有效地对多辆车实行实时管理与监控,有效地提高车辆的指挥管理效率。     

基于熵的炮兵武器系统效能评估

随着炮兵武器系统信息化程度的不断提高和作战样式的发展,如何根据这些变化进行科学、准确的效能评估对其作战运用等具有重要的现实意义.根据目前及将来可能的炮兵武器系统运用特点,将其划分为信息力、打击力、机动力、防护力和保障力五个分系统,用信息熵来度量各系统完成规定任务的程度,并以此为基础,提出了一种评估炮兵武器系统效能的方法,建立了评估模型,结合Matlab所绘图形对模型作了深入的分析,得出了炮兵武器系统效能与信息量并不是简单的正比关系,其增加速度经历了一个"快速增加→增加变缓→降低→趋于稳定值0"的变化过程的结论.     

调整接收站测距同步脉冲的双基地雷达测距新方法

提出了双基地雷达测距的一种新方法,该方法通过调整接收站测距同步脉冲的延时,使接收站对双基信号跟踪时坐标跟踪系统的输出为单基距.给出了调整接收站测距同步脉冲测距的原理及测距同步脉冲延时调整量的控制计算流程,给出了计算的数学模型,针对典型的目标航迹进行了仿真,仿真结果表明了该方法的可行性.该方法在将单基雷达改造为双基雷达时,可避免对原系统核心的软、硬件进行大的改装,使改装简单可行.     

导弹最优突防机动方式研究

将导弹的突防-拦截问题简化到某一平面上,基于此问题的非线性模型,确定了以突防导弹侧向机动为输入,拦截导弹脱靶量为输出的非线性状态方程.针对所研究问题的最优控制类型,构造了系统的Hamilton函数,并通过极大值原理,研究了在平面内导弹机动能力一定的情况下最优规避机动方式.对于简化后的系统线性模型,以机动方式的基波分量为输入,用伴随系统分析方法,通过拦截导弹脱靶量的稳态解,计算了最优的机动频率.     

Bayesian enhanced decision making for deteriorating repairable systems with preventive maintenance

Since a system and its components usually deteriorate with age, preventive maintenance (PM) is often performed to restore or keep the function of a system in a good state. Furthermore, PM is capable of improving the health condition of the system and thus prolongs its effective age. There has been a vast amount of research to find optimal PM policies for deteriorating repairable systems. However, such decisions involve numerous uncertainties and the analyses are typically difficult to perform because of the scarcity of data. It is therefore important to make use of all information in an efficient way. In this article, a Bayesian decision model is developed to determine the optimal number of PM actions for systems which are maintained according to a periodic PM policy. A non‐homogeneous Poisson process with a power law failure intensity is used to describe the deteriorating behavior of the repairable system. It is assumed that the status of the system after a PM is somewhere between as good as new for a perfect repair and as good as old for a minimal repair, and for failures between two preventive maintenances, the system undergoes minimal repairs. Finally, a numerical example is given and the results of the proposed approach are discussed after performing sensitivity analysis. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2008     

Scheduling of depalletizing and truck loading operations in a food distribution system

This paper studies a scheduling problem arising in a beef distribution system where pallets of various types of beef products in the warehouse are first depalletized and then individual cases are loaded via conveyors to the trucks which deliver beef products to various customers. Given each customer's demand for each type of beef, the problem is to find a depalletizing and truck loading schedule that fills all the demands at a minimum total cost. We first show that the general problem where there are multiple trucks and each truck covers multiple customers is strongly NP‐hard. Then we propose polynomial‐time algorithms for the case where there are multiple trucks, each covering only one customer, and the case where there is only one truck covering multiple customers. We also develop an optimal dynamic programming algorithm and a heuristic for solving the general problem. By comparing to the optimal solutions generated by the dynamic programming algorithm, the heuristic is shown to be capable of generating near optimal solutions quickly. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2003