基于实时预报的舰载火控稳定跟踪控制技术

针对火控稳瞄系统存在较大的不确定性及干扰,其特征参数,如固有频率、阻尼以及负载干扰等,将随着被控炮之间差异、载弹量、目标位置的变化及工作海况的影响而产生较大变化的特点,提出了一种PFC-PID串级透明控制策略,通过内环PID控制来提高抗干扰性,外环采用预测函数控制来获得良好的跟踪性能和强鲁棒性。针对舰载火控系统的稳定瞄准中的预测函数控制,提出了船舶运动实时预报问题,根据不同海况、不同船舶的惯导信号特性的不同特点,研究了一种基于自适应长自回归模型和径向基函数神经网络芯片ZISC78的船舶运动实时预报方法。通过对射击过程的仿真,表明基于实时预报的PFC-PID串级透明控制完全可以满足舰载火控系统战技指标,且算法简单,鲁棒性好,是一种实用的火控算法。     

基于多层授权体制的档案全文检索系统设计与实现

档案资料不同于普通的信息资源,其在保密性和专属性上有较高的要求。研 究了在网络环境下建设数字档案全文检索系统时遇到的问题,分析了原有授权体制存在的 弊端,提出了一种基于角色、用户分离的多层授权体制,并在实际系统建设中应用此授权体 制,实现了高效的全文检索和安全、可靠、灵活的访问控制。     

亚超结合反舰导弹控制规律的选择与分析

针对现代海战的特点,分析了现代海战对反舰导弹的性能需求,提出了亚超结合反舰导弹是未来反舰导弹的发展方向。进一步分析了亚超结合反舰导弹对控制系统的要求,并对未来亚超结合反舰导弹控制系统控制规律的选取作了研究分析,最后提出了亚超结合反舰导弹设计的主要关键技术和应注意的几个问题。     

航空电子综合火控系统驾驶员操作程序(POP)仿真

驾驶员操作程序(POP)是航电综合设计最重要的顶层设计文件,其仿真对支持总体设计具有不可替代的作用。首先从整个航空火控系统的角度阐述了POP的组成及任务操作,然后介绍了POP仿真模型的建立方法和制作思路,并对某型飞机航电综合火控系统POP进行了仿真实现。其结果可用于评价飞机航电综合火控系统的POP操作逻辑关系的正确性。     

Fixed‐interval joint‐replenishment policies for distribution systems with multiple retailers and stochastic demand

We consider a distribution system consisting of a central warehouse and a group of retailers facing independent stochastic demand. The retailers replenish from the warehouse, and the warehouse from an outside supplier with ample supply. Time is continuous. Most previous studies on inventory control policies for this system have considered stock‐based batch‐ordering policies. We develop a time‐based joint‐replenishment policy in this study. Let the warehouse set up a basic replenishment interval. The retailers are replenished through the warehouse in intervals that are integer multiples of the basic replenishment interval. No inventory is carried at the warehouse. We provide an exact evaluation of the long‐term average system costs under the assumption that stock can be balanced among the retailers. The structural properties of the inventory system are characterized. We show that, although it is well known that stock‐based inventory control policies dominate time‐based inventory control policies at a single facility, this dominance does not hold for distribution systems with multiple retailers and stochastic demand. This is because the latter can provide a more efficient mechanism to streamline inventory flow and pool retailer demand, even though the former may be able to use more updated stock information to optimize system performance. The findings of the study provide insights about the key factors that drive the performance of a multiechelon inventory control system. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 637–651, 2013     

Directional change‐point detection for process control with multivariate categorical data

Most modern processes involve multiple quality characteristics that are all measured on attribute levels, and their overall quality is determined by these characteristics simultaneously. The characteristic factors usually correlate with each other, making multivariate categorical control techniques a must. We study Phase I analysis of multivariate categorical processes (MCPs) to identify the presence of change‐points in the reference dataset. A directional change‐point detection method based on log‐linear models is proposed. The method exploits directional shift information and integrates MCPs into the unified framework of multivariate binomial and multivariate multinomial distributions. A diagnostic scheme for identifying the change‐point location and the shift direction is also suggested. Numerical simulations are conducted to demonstrate the detection effectiveness and the diagnostic accuracy.© 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013     

Interpreting the Nuclear Non-Proliferation Treaty

Interpreting the Nuclear Non-Proliferation Treaty, by Daniel H. Joyner. Oxford University Press, 2011. 192 pages, $100.     

A NEW STANDARD FOR PREEMPTIVE MILITARY ACTION AGAINST WMD THREATS

International law clearly requires an imminent threat of attack as a justification for the preemptive use of military force. However, the standard definition of an imminent threat was derived centuries before the development of nuclear, chemical, or biological weapons or ballistic missiles and other delivery systems that can reach their targets in a matter of minutes. Any use of force to alleviate threats posed by weapons of mass destruction (WMD) prior to tactical warning of the actual launch of such weapons falls into the legally and ethically controversial category of “anticipatory self-defense,” leaving decision makers potentially liable to prosecution for war crimes. Effective and ethical enforcement of nonproliferation therefore demands a standard for imminence of threat broad enough to allow military action as a last resort but sufficiently restrictive to prohibit indiscriminate action against suspected WMD programs. Following a critical review of selected literature and cases on preemption, the author proposes a new standard for preemptive military action: the existence of operational WMD, or a clandestine program to develop WMD, in contravention of international law. The author discusses the implications of this new proposed standard, which at the time of writing would permit preemptive attack against WMD-armed terrorist groups but prohibit it against all states except Iran and possibly North Korea.     

GETTING BETTER ALL THE TIME

Detect and Deter: Can Countries Verify the Nuclear Test Ban?, by Ola Dahlman, Jenifer Mackby, Svein Mykkeltveit, and Hein Haak. Springer, 2011. 279 pages, $129.     

Building the next nuclear community

This viewpoint takes stock of the changes in the strategic nuclear landscape in recent decades and reflects on its consequences on the policy community. It finds that the number and scope of issues have expanded considerably; they have manifested themselves in many more regions of the world; and they have become deeply politicized and polarized. The consequences have been twofold: the nuclear policy field has seen the development of an increasingly diverse expert community composed of highly specialized functionalists and regionalists, and it has become ever more divided into two entirely separate ideological camps—one that believes in deterrence, the other in disarmament. The stove-piping of expertise and the widening gap between deterrence and disarmament ideologies are immensely problematic because, in different ways, they stand in the way of the emergence of a better and safer nuclear future. Looking ahead, it is critical to “bust the silos of expertise” and to build bridges between the deterrence and disarmament ideological camps. Only such a community-building effort will help solve today’s and tomorrow’s nuclear challenges.