基于Q学习的双机协同探测路径规划方法

建立双机协同被动探测的任务模型, 运用模糊理论对问题状态空间进行泛化, 针对不同的探测阶段给出了目标转移函数的不同形式, 通过合理定义动作空间和奖励函数将问题描述为Markov决策过程。给出了双机协同被动雷达探测的模糊Q学习算法, 并对算法进行仿真, 仿真结果表明, 该方法能够有效控制双机的飞行路径, 实现对机动及非机动目标的有效探测。     

中断角度跟踪的战斗机机动控制方法

基于跟踪雷达角度自动跟踪系统特性,提出了战斗机中断雷达角度跟踪的机动轨迹控制策略。推导了跟踪雷达角度自动跟踪系统的系统传递函数,研究了跟踪误差产生机理。以二维平面内导弹攻击为例,分析了导弹与战斗机的二阶相对运动模型。在此基础上,基于闭环反馈控制思想,提出了战斗机通过机动实现角度拖引,中断雷达角度跟踪的控制方法,推导了战斗机的机动轨迹控制律,给出了其解析形式。通过数值仿真,分析了该方法的适用性,为战斗机飞行员制定决策提供了依据。     

基于连通图的动态可重构多机协同干扰方法

针对多机空战电子对抗中,干扰目标分配和协同干扰资源选择问题,在分析空战有源电子干扰面临复杂电磁环境、雷达跟踪干扰源、干扰目标分配和干扰资源选择等问题的基础上,建立双机协同干扰数学模型,分析协同干扰对测角误差影响因素,提出基于连通图的动态可重构双机协同干扰方法,并应用于典型的“磨刀匠”攻击战术。仿真结果表明,基于连通图的动态可重构双机协同干扰方法,能够实现多机编队协同作战时的最优协同干扰资源和干扰目标选择,实现对单脉冲机载火控雷达协同角度欺骗干扰,且算法计算时间完全符合协同干扰需求,为新型战斗机协同干扰提供了借鉴。     

数据链信息连续引导雷达搜索策略

机外数据链信息引导雷达搜索目标是战斗机实现隐身战斗任务的重要技术手段。采用概率方法分别建立多拍连续数据链引导信息与累积发现概率、累积被检测概率之间的关系,通过动态规划方法建立多阶段动态决策模型,满足雷达探测性能的条件下,获得最优的雷达隐身性能。最后,在典型作战场景下对模型进行仿真验证,结果表明所提的最优搜索策略相比于经验搜索策略能减少雷达辐射时间67.5%,相比于模型保守策略减少83.75%。     

双机IRST系统协同自主引导搜索技术

双机IRST系统协同搜索是一种重要的无源探测手段。分析了双机IRST协同搜索关键问题,建立了自主引导搜索的数学模型,通过长机IRST系统探测到目标的角度信息,并利用IRST系统的探测距离范围限制计算目标在僚机机体系中的角度范围,据此引导僚机IRST系统对目标存在区域进行搜索。对于僚机搜索范围提出顺序搜索和中心搜索两种搜索策略,仿真结果表明了引导搜索的有效性,中心搜索比顺序搜索效率更高,所需时间更短。其中,根据中心搜索策略提出的两种一次搜索方案的仿真结果验证了成功引导搜索的性质,对研究双机IRST自主引导搜索系统配置具有一定的参考价值。     

面向低截获的雷达/红外控制与跟踪方法

机载雷达低截获性能是作战飞机隐蔽接敌和先敌发现的重要保障。将相控阵雷达控制灵活、红外搜索与跟踪(IRST)隐蔽性好等特点紧密结合,从尽可能降低雷达探测照射时间获取优良低截获性能角度出发,提出了一种复杂战场环境下机载雷达/红外融合探测控制与跟踪方法。首先研究了机载雷达/红外协同探测跟踪系统图,然后研究了自适应多速率交互式多模型融合跟踪方法,并给出了协同探测传感器控制策略、滤波发散与目标机动判断准则,最后通过仿真分析,验证了新算法的有效性。     

一种主/被动雷达协同探测跟踪模式及算法研究

为了提升地空导弹武器系统体系抗干扰及隐蔽性作战能力,结合新装备主动雷达和基于时差法测量的被动雷达系统各自技术优势,提出了一种主动雷达辅助的被动雷达协同探测跟踪模式,并针对该模式研究设计了一种协同探测跟踪算法。通过引入模糊推理函数,利用新息方差实际值和量测误差协方差变化率值作为模糊输入控制量,实时控制主动雷达的开关机工作,不仅实现了对主动雷达的精确化和实时化控制,而且提高了系统跟踪精度。通过Monte Carlo仿真,进一步验证了协同模式的合理性以及改进算法的有效性和正确性。     

多机协同探测相控阵雷达短时任务分配方法

针对多机协同探测中雷达资源合理配置问题,提出了一种相控阵雷达短时任务分配模型。首先,分别根据克拉美罗界和信号检测理论对机载相控阵雷达跟踪能力和搜索能力进行量化;接着,建立短时任务条件下工作时间最小的相控阵雷达管理优化函数。仿真结果表明,短时任务分配模型能够提升雷达的工作效能。     

IRST牵引机载预警雷达的探测效能评估与仿真

为定量分析和评估机载红外搜索跟踪系统（IRST）牵引探测模式对雷达探测效能的影响,以雷达探测效能概率作为评估指标,模拟IRST牵引雷达探测的过程,建立基于多波位搜索的牵引成功概率模型,确定满足一定牵引成功概率下的雷达搜索范围,并根据特定的目标特性推导雷达探测效能概率表达式。仿真结果表明,该模式利用红外的高精度角度信息进行牵引,极大缩小了雷达的搜索区域和搜索时间,加快雷达对目标的截获过程,并利用波束驻留时间的增加提高了雷达的发现概率,提升了雷达的探测效能。     

基于混沌粒子群优化算法的战斗机使用空射诱饵的攻击决策

针对战斗机使用空射诱饵进行一对一空战的攻击决策问题,提出了一种基于混沌粒子群算法的决策方法。建立了战斗机、空射诱饵和目标机的运动模型;在分析战斗机空战能力、空射诱饵欺骗能力和目标机威胁程度的基础上,建立了攻击决策指标函数;最后,建立了基于混沌粒子群算法的攻击决策模型。仿真结果表明,该方法可以使空射诱饵更好地发挥欺骗作用,提高战斗机生存能力。     

Interfacial reaction and shear strength of SnAgCu-xNi/Ni solder joints during aging at 150 °C

The interfacial microstructure and shear strength of Sn3.8Ag0.7Cu-xNi (SAC-xNi, x = 0.5, 1, and 2) composite solders on Ni/Au finished Cu pads were investigated in detail after aging at 150 °C for up to 1000 h. The interfacial characteristics of composite solder joints were affected significantly by the weight percentages of added Ni micro-particles and aging time. After aging for 200 h, the solder joints of SAC, SAC-0.5Ni and -1Ni presented duplex intermetallic compound (IMC) layers regardless of the initial interfacial structure on as-reflowed joints, whose upper and lower IMC layers were comprised of (CuNi)₆Sn₅ and (NiCu)₃Sn₄, respectively. Only a single (NiCu)₃Sn₄ IMC layer was ever observed at the SAC-2Ni/Ni interface on whole aging process. Based on the compositional analysis, the amount of Ni within the IMC regions increased as the proportion of Ni addition increased. The IMC (NiCu)₃Sn₄ layer thickness on the interface of SAC and SAC-0.5Ni grew more slowly when compared to that of SAC-1Ni and -2Ni, while for the (CuNi)₆Sn₅ layer the reverse is true. Except the IMCs sizes are increased with increased aging time, the interfacial IMCs tended to transfer their morphologies to polyhedra. In all composite joints testing, the shear strengths were approximately equal to non-composite joints. The fracturing observed during shear testing of composite joints occurred in the bulk solder, indicating that the SAC-xNi/Ni solder joints had a desirable joint reliability.     

有机发光二极管中ADN掺杂ErQ的1.54μm电致发光

自行设计了基于8-羟基喹啉铒(ErQ)为发射层(EMLs)和二硝酰胺铵(ADN)为蓝光主体材料的近红外有机发光二级管.器件的基本结构为(p-Si/NPB/EML/Bphen/Bphen:Cs2CO3/Sm/Au),设计并比较了三套不同发射层结构(ErQ/ADN为双层结构器件,(ErQ/ADN)×3为多层结构器件,ErQ:ADN为掺杂结构器件)的器件.三组器件在一定的偏压下,均可发出1.54μm的光,对应三价铒离子4I13/2→4I15/2的跃迁.其中,ADN:ErQ(1∶1)掺杂结构的近红外电致发光强度是ADN/ErQ双层结构中的三倍.此外,不同掺杂浓度的ADN:ErQ复合膜做了以下表征:吸收谱、光致发光谱和荧光寿命谱.实验结果证实了在近红外电致发光过程中存在从ADN主体分子到ErQ发射分子的高效率的能量转移.     

BNBST无铅压电陶瓷的制备工艺研究

设计了（Bi0.55Na0.5）1-X（BaaSrb）xTiO3（BNBST[100x-100a／100b]）无铅压电陶瓷新体系。该体系压电陶瓷具有工艺特性及压电响应好，压电常数高的特点，且有实际应用前景的新型压电陶瓷材料体系。采用传统的陶瓷工艺制备了（Bi0.55Na0.5）1-X（BaaSrb）xTiO3无铅压电陶瓷，研究了制备工艺参数对其物化结构性能的影响。生料的热重-差热（TGA-DTA）分析表明，粉料合成过程中，先是SrTiO3、BaTiO3的形成，然后是（Bi0．5Na0．5）Tio，的形成，同时三者形成固溶体；密度测试表明，陶瓷的体积密度随烧结温度的升高而增大，可较易获得理论密度94％的陶瓷；X-射线能谱分析（EDAX）研究表明，陶瓷的Bi、Na的挥发随着烧结温度的升高而加剧。研究结果表明，要制备性能优良的无铅压电陶瓷，需要精确控制制备工艺。     

Emerging interconnects: a state-of-the-art review and emerging solutions

Aluminium was a primary material for interconnection in integrated circuits (ICs) since their inception. Later, copper was introduced as interconnect material which has better metallic conductivity and resistance to electromigration. As the aggressive technology scaling continues, the copper resistivity increased because of size effects, which causes increase in delay, power dissipation and electromigration. The need to reduce the resistor-capacitor??????? delay, dynamic power utilisation and the crosstalk commotion is as of now the fundamental main impetus behind the presentation of new materials. The purpose of this paper is to do a survey of interconnect material used in IC from introduction of ICs to till date. This paper studies and reviews new materials available for interconnect application which are optical interconnects, carbon nanotube (CNT), graphene nanoribbons (GNRs) and silicon nanowires which are alternatives to copper. While doing a survey of interconnect material, it is found that multiwalled CNTs, multilayer GNR and mixed CNT bundles are promising candidates and are ultimate choice that can strongly address the problems faced by copper but on integration basis copper would last for coming years.     

钠离子对poly(dT).poly(dA).poly(dT)三螺旋DNA分子呼吸模式的影响

利用分子结构的螺旋对称性,建立了一个包括钠离子的三链DNA分子poly(dT)*poly(dA)*poly(dT)的晶格动力学模型,计算了poly(dT)*poly(dA)*poly(dT)的氢键呼吸模式.结果发现钠离子的加入明显地淬灭了位于较低频率的几个最为强烈的Hoogensteen氢键呼吸模式,而对Watson-Crick氢键呼吸模式影响不明显,这说明钠离子能提高poly(dT)*poly(dA)*poly(dT)三螺旋结构的稳定性.该计算结果很好地解释了poly(dT)*poly(dA)*poly(dT)的热融化实验.     

聚对苯撑苯并双(口恶)唑发光及其器件制备

采用光谱技术,研究了聚对苯撑苯并双(口恶)唑(PBO)溶液的光敏发光特性,并用相对法估算出溶液发光效率在50%范围.结合光谱技术、半导体电学和电化学等研究手段,具体研究了以PBO为发光层的单层电致发光器件,研究结果显示,电致发光与薄膜的光致发光有具有相同的发光中心,峰值位于510 nm左右.同时发现,由于存制备过程中不同处理条件使得不同厚度薄膜残留的掺杂物质浓度不同,从而引起薄膜的导电性的不同.使得器件的阈值场强随PBO厚度的减小而逐渐增加.     

人小肠粘膜免疫酶的定位研究—光镜和电镜免疫组织化学染色法

本文对免疫酶组织化学的样品制备程序和染色方法做了详细的阐述。用直接法、间接法和ABC法,对人小肠免疫酶的定位,进行了光镜和电镜的观察,染色阳性反应显著,获得了满意的效果。并对染色技巧做了分析和探讨。     

Arsenic deposition as a precursor layer on silicon (211) and (311) surfaces

We investigate the properties of arsenic (As) covered Si(211) and Si(311) surfaces by analyzing data from x-ray photoelectron spectroscopy (XPS) and low-energy electron diffraction (LEED) images. We then create a model using total surface energy calculations. It was found that both Si(211) and Si(311) had 0.68±0.08 surface As coverage. Si(211) had 0.28±0.04 Te coverage and Si(311) had 0.24±0.04 Te coverage. The Si(211) surface replaces the terrace and trench Si atoms with As for a lower surface energy, while the Si edge atoms form dimers. The Si(311) surface replaces all terrace atoms and adsorbs an As dimer every other edge site. These configurations imply an improvement in the mean migration path from the bare silicon surface by allowing the impinging atoms for the next epitaxial layer, tellurium (Te), to bind at every other pair of edge atoms, and not the step terrace sites. This would ensure a nonpolar, B-face growth.     

Joint estimation of TOA and DOA in IR-UWB system using a successive propagator method

Impulse radio ultra-wideband (IR-UWB) ranging and positioning require accurate estimation of time-of-arrival (TOA) and direction-of-arrival (DOA). With receiver of two antennas, both of the TOA and DOA parameters can be estimated via two-dimensional (2D) propagator method (PM), in which the 2D spectral peak searching, however, renders much higher computational complexity. This paper proposes a successive PM algorithm for joint TOA and DOA estimation in IR-UWB system to avoid 2D spectral peak searching. The proposed algorithm firstly gets the initial TOA estimates in the two antennas from the propagation matrix, then utilises successively one-dimensional (1D) local searches to achieve the estimation of TOAs in the two antennas, and finally obtains the DOA estimates via the difference in the TOAs between the two antennas. The proposed algorithm, which only requires 1D local searches, can avoid the high computational cost in 2D-PM algorithm. Furthermore, the proposed algorithm can obtain automatically paired parameters and has better joint TOA and DOA estimation performance than conventional PM algorithm, estimation of signal parameters via rotational invariance techniques algorithm and matrix pencil algorithm. Meanwhile, it has very close parameter estimation to that of 2D-PM algorithm. We have also derived the mean square error of TOA and DOA estimation of the proposed algorithm and the Cramer-Rao bound of TOA and DOA estimation in this paper. The simulation results verify the usefulness of the proposed algorithm.     

系统级封装新型埋入式电源滤波结构的研究

在高密度小尺寸的系统级封装(SiP)中,对供电系统的完整性要求越来越高,多芯片共用一个电源网路所产生的电压抖动除了会影响到芯片的正常工作,还会通过供电网路干扰到临近电路和其他敏感电路,导致芯片误动作,以及信号完整性和其他电磁干扰问题.这种电压抖动所占频带相当宽,几百MHz到几个GHz的中频电源噪声普通方法很难去除.结合埋入式电容和电源分割方法的特点,提出一种新型高性能埋入式电源低通滤波结构直接替代电源/地平面.研究表明,在0.65～4GHz的频带内隔离深度可达-40～75 dB,电源阻抗均在0.25ohm以下,实现了宽频高隔离度的高性能滤波作用.分别用电磁场和广义传输线两种仿真器模拟,高频等效电路模型分析这种低通滤波器的工作原理以及结构对隔离性能的影响,并进行了实验验证.