基于 ∆TOA 和方位角测量辅以间歇高度信息的双基地定位跟踪技术

本文讨论了双基地雷达系统中一种以收站△TOA和方位角测量为基础并辅以发射站传送的间歇高度信息的运动目标三维定位跟踪算法,详细分析了该技术的定位原理。在电子对抗条件下,发射站数据往往难以连续传送到接收站加以融合,因此有必要对间断传送的数据加以利用的方法进行研究。本文通过典型目标航迹的计算机仿真对该算法的性能做了评估。由于这种融合方法在双基地研究领域尚属初探,因此有待于在今后的研究中加以完善。     

只测角两站被动定位系统中虚假定位点的识别方法研究

多站被动定位中,虚假定位点的识别问题是电子侦察中尚待解决的一个重要问题。本文研究包含一个运动站的只测角两站被动定位系统,提出先用扩展Kalman滤波对多个辐射源精确定位,然后通过空间相关处理识别虚假定位点的方法,大量的计算机仿真结果表明,上述识别方法在两目标张角大于测角误差的均方根值时,具有良好的识别效果。系统识别出的真实定位点,其定位精度可达单目标环境下的同等定位精度。     

Approximation methods for the analysis of a multicomponent,multiproduct assemble‐to‐order system

In this article, we consider the performance evaluation of a multicomponent, multiproduct assemble‐to‐order (ATO) system. Each component is managed independently using a base‐stock policy at a supply facility with limited production capacity and an infinite buffer. The arrivals of demands follow a multivariate Poisson process and unfilled demands are backlogged. Because exact analysis of the proposed system is not feasible, we propose two approximation methods which provide upper and lower bounds for various performance measures such as fill rate, average waiting time, and average number of backorders of the proposed system. Our computational experiments demonstrate the effectiveness of the two approximation methods under various system settings. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011     

粒子滤波在误差配准中的应用

系统偏差严重影响了多部雷达航迹的互联和目标状态的融合,因此如何解决误差配准成为一个关键问题。因为系统偏差和雷达的量测之间是一种非线性关系,所以无法直接使用Kal-man等线性滤波直接进行系统偏差的估计。为解决这一问题,利用非线性的粒子滤波器(PF),对目标状态和系统偏差的估计进行了探讨,为了对比其性能,设计了一种扩展Kalman滤波算法。仿真结果表明PF在误差配准中的应用是可行的,性能高于扩展Kalman滤波。     

锆酸铅PbZrO3序参量的量子饱和

在503 K反铁电体PbZrO3发生立方-正交相变,序参量是反平行离子位移引起的超晶格;在低温相时,PbZrO3的反铁电超晶格反射强度随温度的变化成正比,可以由考虑量子效应的Landau唯象理论加以描述;高于室温时,Γ25超晶格反射强度显示了不同的温度依赖性。     

Dynamic order acceptance and capacity planning on a single bottleneck resource

We present a tactical decision model for order acceptance and capacity planning that maximizes the expected profits from accepted orders, allowing for aggregate regular as well as nonregular capacity. The stream of incoming order arrivals is the main source of uncertainty in dynamic order acceptance and the company only has forecasts of the main properties of the future incoming projects. Project proposals arrive sequentially with deterministic interarrival times and a decision on order acceptance and capacity planning needs to be made each time a proposal arrives and its project characteristics are revealed. We apply stochastic dynamic programming to determine a profit threshold for the accept/reject decision as well as to deterministically allocate a single bottleneck resource to the accepted projects, both with an eye on maximizing the expected revenues within the problem horizon. We derive a number of managerial insights based on an analysis of the influence of project and environmental characteristics on optimal project selection and aggregate capacity usage. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

The impact of component commonality on composite assembly policies

Assemble in Advance (AIA) policy reduces assembly cost due to advance planning, while Assemble to Order (ATO) policy eliminates assembly of excessive (more than demanded) units. The tradeoffs between the two policies have been studied in the past for single product environments. Moreover, it was shown that it is beneficial to employ AIA and ATO simultaneously. In this article, we study the employment of such a composite assembly policy in a multiproduct environment with component commonality. When common components are used, ATO may also enable us to benefit from the risk pooling effect. We provide important managerial insights such as: the multiperiod problem is myopic and changes in inventory levels due to the use of common components, and demonstrate the potential profit increase compared to other policies.© 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007     

卡尔曼滤波在水雷引信目标定位中的应用

介绍了用于水雷引信的目标跟踪定位卡尔曼滤波算法,推导了滤波公式,给出了仿真结果．经分析得知,利用该算法可有效提高目标运动要素估计精度．     

光栅过滤法测试陶瓷磨削表面残余应力

采用表面形貌技术对陶瓷磨削表面残余应力进行测试研究,对表面粗糙度曲线经过数据截取、滤波以及规范化处理后可得到表面挠度曲线,认为,此方法与X射线衍射法相比测试结果较接近,是测试残余应力的有效方法;其数据处理过程是保证测试精度的关键;挠度变化是个渐变的过程。     

引入测频信息进行无源被动定位的方法研究

无源被动定位技术中一个重要问题，是如何使定位的约束条件尽可能地少，即尽可能地提高方法的可操作性。只利用测角信息（ＤＯＡ）的定位方法，由于可观测性的要求，在单观测平台对运动目标定位时，常常需要观测平台作特殊的机动运动，这种约束给实际操作带来很大不便。本文提出了一种引入测频信息对运动目标进行定位的定位方法，并给出了可观测性分析。运用该定位法定位，观测平台的运动形式可以任意，特别有意义的是，在满足某些条件情况下观测平台还可以完全静止不动。