Capacitated lot‐sizing and scheduling with parallel machines,back‐orders,and setup carry‐over

We address the capacitated lot‐sizing and scheduling problem with setup times, setup carry‐over, back‐orders, and parallel machines as it appears in a semiconductor assembly facility. The problem can be formulated as an extension of the capacitated lot‐sizing problem with linked lot‐sizes (CLSPL). We present a mixed integer (MIP) formulation of the problem and a new solution procedure. The solution procedure is based on a novel “aggregate model,” which uses integer instead of binary variables. The model is embedded in a period‐by‐period heuristic and is solved to optimality or near‐optimality in each iteration using standard procedures (CPLEX). A subsequent scheduling routine loads and sequences the products on the parallel machines. Six variants of the heuristic are presented and tested in an extensive computational study. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009     

雷达信号调制类型自动识别的一种新方法

雷达辐射源信号调制类型的自动识别是电子战系统的关键技术之一.深入分析了小波变换法提取信号脉内特征的基本原理,提出一种基于小波变换法提取的脉内特征自动判别信号调制类型的新方法.仿真结果表明,在满足一定的信噪比条件下,新方法能准确识别给定信号的调制类型.     

IP over DDN在某导弹试验指挥舰系统中的设计与应用

在某导弹试验指挥舰系统建设中,针对直接使用原卫星通信设备,存在接口数量、接口标准和通信带宽等方面的局限性,采用IP over DDN技术,解决了通信带宽不足和该条件下的多业务接入问题.对于实时应用特点,选用了IP组播协议进行网络配置,进行系统设计,既保护了前期投资,又较好地满足了海上武器试验指挥系统的通信需求.     

适于弹载平台的正交多载波雷达波形设计

设计了一种适于弹载平台的多载波雷达波形,模糊函数近似理想图钉型,且波形设计灵活,参数选择自由度高,与传统的单载波雷达波形相比,被截获概率大大降低。给出了一种具有9个子载波数量的雷达基带波形设计方案,为进一步改善主副瓣比,采用了脉间波形捷变及子载波频域加权技术,实现结果表明在基带信号带宽为9 MHz时主副瓣比可达-35 d B以下,且不同调制序列得到的雷达波形具有良好的低互相关特性,特别适合于多部弹载雷达协同工作场合。     

实验课课堂教学有效性的组织策略

本文从教学的有效性理论出发,通过分析,给出了在实验课课堂教学中实行滚动式、分层次教学的可行性分析,给出了具体的组织管理细节。讨论了以实验课为试点的优势及其可行性方案。     

一种基于交叉关联积分的功放无意调制识别方法

针对同频率连续波信号中的功放指纹分析问题,提出一种基于相空间交叉关联积分的无意调制识别方法(CCI-UMI).该方法通过对功放无意调制的机理分析和对重构矢量沿轨迹概率(PDT)的理论分析,建立了相轨迹比较的基本理论依据和参数选择方法.采用多尺度交叉关联积分算法,在重构相空间实现了对信号细微差别的灵敏比较.对任意波发生器两路通道实测数据的分类实验表明:本方法识别率较高,经合理选择参数,在低信噪比下可获得比功率谱方法和相空间微分方法更好的分类性能.     

近地卫星Ka频段数传链路抗雨衰ACM模式设计

针对近地卫星数传时的信道时变性和严重的Ka频段雨衰现象,采用自适应编码调制（ACM）技术能够充分利用链路资源,相对于传统的固定编码调制方式,进一步提高了链路的数据吞吐量。提出了近地卫星Ka频段数传链路ACM模式设计方法,在降雨环境下建立Ka频段数传链路模型,根据信道状况确定ACM选用模式;采用基于导频符号的最大似然信噪比估计算法结合移动平均的平滑方法实现信道估计,有效地减小了估计值的波动。仿真结果表明,无论晴天还是雨天,采用提出的卫星数传链路ACM模式设计方法,能够在保证系统可靠性的同时获取较高的数据吞吐量。     

A high performance waveform and a new ranging method for the proximity detector

Signal modulation is an essential design factor for proximity detectors and directly affects the system’s potential performance. In order to achieve the advantages of chaotic codes bi-phase modulation (CCBPM) and linear frequency modulation (LFM) simultaneously, this paper designed a waveform which combined chaotic codes bi-phase modulation and linear frequency modulation (CCBPM–LFM) for proximity detectors. The CCBPM–LFM waveform was analyzed in the aspect of time delay resolution (TDR) and Doppler tolerance (DT) based on ambiguity function (AF). Then, a ranging method, which we called instant correlation harmonic demodulation (ICHD), was presented for the detector using the CCBPM–LFM waveform. By combining time domain instant correlation with harmonic demodulation, the ICHD solved the problem caused by combination modulation and made the most of the linear frequency modulation (LFM) harmonics and the correlation of chaotic codes. Finally, a prototype was implemented and ranging experiments were carried out. From the theoretical analysis and experimental results, the proximity detector used the CCBPM–LFM waveform has an outstanding detection performance.     

用于堤坝检测的剖面声纳系统实验研究

针对水下堤坝安全检测,提出并设计实现了适合水下机器人等小平台为载体的可用于堤坝安全检测的高分辨率剖面声纳,系统通过获取被测堤坝内部的回波信号,由DSP构成的水下处理单元进行实时信号处理,从而可获得坝体内介质不连续的信息,并由水上分机进行堤坝内部剖面图像的重建及显示。通过水池和外场堤坝工程检测等应用实例,取得了良好的效果,验证了系统技术路线的可行性和性能的稳健性。     

激光末制导炮弹过重力补偿比例导引律的分析

以相对运动方程组为基础,分析了导引律的运动学实质和过重力补偿的信号流图,进而分别对比例导引和基于过重力补偿为常值的过重力补偿比例导引下的弹道进行了对比仿真计算。结果表明,过重力补偿比例导引适用于攻击非机动和机动性不大的目标,落角增大,命中点附近视线偏转和控制过载变大,能够实现对目标的大落角攻顶效应。