某型雷达板级模块测试适配器的设计与实现

某型雷达电路板测试适配器需要对二十多种电路板进行功能测试,被测电路板信号时序复杂,接口定义不统一,给适配器设计带来困难。本文采用通用适配器设计方案成功的解决了问题,实践证明,该适配器设计灵活,大大简化多电路板检测适配器的设计难度,具有一定的工程借鉴价值。     

Optically Tunable Field Effect Transistors with Conjugated Polymer Entailing Azobenzene Groups in the Side Chains

Semiconducting conjugated polymers with photoswitching behavior are highly demanded for field‐effect transistors (FETs) with tunable electronic properties. Herein a new design strategy is established for photoresponsive conjugated polymers by incorporating photochromic units (azobenzene) into the flexible side alkyl chains. It is shown that azobenzene groups in the side chains of the DPP (diketopyrrolopyrrole)‐quaterthiophene polymer ( PDAZO ) can undergo trans/cis photoisomerization in fully reversible and fast manner. Optically tunable FETs with bistable states are successfully fabricated with thin films of PDAZO . The drain‐source currents are reduced by 80.1% after UV light irradiation for ≈28 s, which are easily restored after further visible light irradiation for ≈33 s. Such fast optically tunable FETs are not reported before. Moreover, such current photomodulation can be implemented for multiple light irradiation cycles with good photofatigue resistance. Additionally, thin film charge mobility of PDAZO can be reversibly modulated by alternating UV and visible light irradiations. On the basis of theoretical calculations and GIWAXS data, it is hypothesized that the dipole moment and configuration changes associated with the trans‐/cis‐photoisomerization of azobenzene groups in PDAZO can affect the respective intra‐chain and inter‐chain charge transporting, which is responsible for the optically tunable behavior for FETs with thin films of PDAZO .     

Design of High Capacity Dissoluble Electrodes for All Transient Batteries

Transient electronics is an emerging engineering realm that requires materials, devices, and systematic designs with excellent and stable performance in regular operations, but to physically and chemically disappear at a prescribed time with controlled rates once being triggered by external stimulus, leaving no or minimum remnants. In this article, a high energy density rechargeable battery with a fully transient cathode based on tin (Sn)‐doped vanadium oxide (V₂O₅) is designed. Sn‐doped V₂O₅ nanofibers with a high mass loading of 12 mg cm^?2 are prepared and no conducting additive or binder is added to fabricate full cells. The transient battery exhibits an areal capacity of 2 mAh cm^?2 with a working voltage above 2.0 V and provides 0.27 mAh cm^?2 capacity at a current as high as 17.76 mA cm^?2. Once triggered by potassium hydroxide (KOH) aqueous solution, the full cell can be completely dissolved into the solution within a few minutes to achieve highly transient capability. This work provides a new approach to achieve an all‐transient lithium battery with high areal capacity for transient electronics applications.     

爆炸桥箔加速贮存前后的电爆特性

为了获得爆炸桥箔贮存后的电爆特性,对爆炸桥箔开展了高温(90℃)和高温高湿(80℃,RH95%)条件下的加速寿命试验。利用照相、扫描电镜分析、发火试验和光子多普勒测速(PDV)方法,研究了加速贮存试验前后爆炸桥箔的形貌、电爆特性和飞片速度。结果表明,加速贮存后桥箔的表面均发生了氧化,高温高湿条件下,杂质元素污染及湿度造成桥箔的颜色变化显著,电阻均值由贮存前的30.3 mΩ上升至66.8 mΩ。高温对桥箔的爆发电流、爆发电压和爆发时间没有显著影响。高温高湿贮存后桥箔的爆发电压显著降低。加速贮存后爆炸桥箔在聚酰亚胺基底的附着能力变差。PDV测速结果表明,随着加速贮存时间的延长,飞片速度由3600 m·s~(-1)降至2100 m·s~(-1)(高温)和1200 m·s~(-1)(高温高湿),加速贮存会影响桥箔驱动飞片的能力,高温高湿条件对飞片速度影响更严重。     

新型掠飞末敏弹的捕获概率分析

针对掠飞末敏弹新型扫描机理的作战效能进行评估,研究末敏弹在弹道末段的捕获特性。通过坐标变换的方法得到掠飞末敏弹的扫描线方程,耦合求解其六自由度弹道方程组,得到了弹丸的稳态扫描区域,通过证明扫描依赖区结论,进一步推导求解了捕获概率的解析公式。结果表明：掠飞末敏弹的空间扫描轨迹为螺旋线、扫描区域为圆柱体,平面上的扫描区域为左半椭圆;增加弹丸初速、降低弹丸射角、准确预估目标运动,能有效提升掠飞末敏弹的捕获概率,其中初速的影响更胜一筹;解析公式求得捕获概率与蒙特卡洛打靶法计算结果吻合较好,验证了公式的正确性。     

惯容器及惯容器-弹簧-阻尼器悬架研究进展

介绍了惯容器和惯容器-弹簧-阻尼器(ISD)悬架的概念、提出背景及特点,总结了惯容器结构形式、动力学特征和非线性特性、频率响应特性和击穿现象。从ISD悬架结构形式、性能特点和网络综合理论的应用、ISD悬架空间布置和一体化设计等方面,系统说明了ISD悬架研究进展。归纳总结提出了惯容器及ISD悬架未来的5大研究方向,包括惯容器的创新设计、惯容器非线性研究、ISD悬架网络综合、ISD悬架的应用研究及ISD悬架一体化融合设计。     

弹性翼S-C型末敏弹气动特性研究

采用双向流体-固体耦合方法对无伞末敏弹进行气动弹性分析,研究了末敏弹尾翼在气动力作用下的变形规律,并对尾翼变形后的末敏弹系统进行气动特性分析,总结了末敏弹气动参数、尾翼挠曲变形随运动攻角的变化规律。研究结果表明,末敏弹的阻力系数和转动力矩系数均随着攻角的增大呈先增加、后减小的趋势,升力系数则随着攻角的增大呈单调递增趋势;自由飞行试验结果显示,与刚性翼末敏弹相比,弹性翼末敏弹的气动参数仿真值与试验值更为贴近。     

三点起爆同步误差对尾翼EFP成型性能的影响

针对三点起爆同步误差对尾翼爆炸成型弹丸(EFP)成型的影响问题,利用LS-DYNA有限元软件,分析了三点起爆同步误差引起的爆轰波不对称碰撞以及药型罩在复合爆轰波作用下的压垮过程,研究了三点起爆同步误差对EFP的尾翼形成及飞行速度的影响。结果表明,三点起爆同步误差造成三叉形高压区和三叉形中心超高压区偏离药型罩中心,使EFP尾翼成型不规则;三点起爆成型装药形成较佳尾翼EFP应满足的最大起爆同步误差为100ns,且尽量使中间起爆点起爆同步误差约为最大同步误差的一半,有利于降低尾翼EFP的水平分速度,提高飞行稳定性。     

一种新型启发式搜索算法研究

提出了一种用于解决复杂优化问题的新的启发式算法--蚁群算法.采用该算法进行了无人机的航路规划,为求解无人机航路规划问题提供了一种新的算法.该算法对传统蚁群算法进行了改进,更好地解决了无人机的航路规划问题,文中进行了相应的仿真,仿真结果表明了算法的有效性.     

基于自适应卡尔曼滤波器的神经网络算法

针对传统神经网络算法速度慢,容易陷入局部极值的缺点,提出将自适应卡尔曼滤波应用于人工神经网络的训练算法中.把前馈网络中的所有权值、阈值作为自适应卡尔曼滤波算法的状态,网络输出为算法的观测.仿真结果表明, 该算法比BP算法在收敛速度方面有明显提高.