基于AD8302的瞬时测频接收机

为了简化瞬时测频(IFM)接收机的结构、提高集成度,设计了采用AD8302为核心的IFM接收机,并分析了该测频接收机的灵敏度、动态范围、测频精度等关键指标。最后制作了实验系统对该IFM接收机的可行性进行了验证,实验结果表明采用AD8302实现的IFM接收机可以提高测频精度,简化接收机结构。     

In situ characterization of Ni-rich NMC811 thin films prepared by sol-gel method using different scanning probe microscopy techniques

In this paper, LiNi_0.8Co_0.1Mn_0.1O₂ (NMC811) thin films were prepared by the sol-gel method based on different parameter conditions, and the microstructure and electrochemical properties of the films were compared to obtain the film sample under the best preparation parameters. In order to explain the formation mechanism of cell battery performance based on the NMC811 cathode at the nano scale, electrochemical strain microscopy, conductive atomic force microscopy and Kelvin probe force microscopy are specifically utilized to study the changes of NMC811 thin film in electrochemical deformation, conductivity, and potential distribution under different electrical and thermal fields. The results indicate that the local amplitude, conductivity, and electrical potential of thin film in the scanning region increases with the voltage from 0 V to 3 V and the temperature from 25 °C to 150 °C. However, the electrochemical deformation, conductivity, and potential of the film decrease significantly when the voltage is applied to 4 V or the temperature rises to 200 °C.These results provide visual evidence for the influence of external field on the phase structure change and lithium-ion diffusion behavior of NMC811 thin film.     

多功能三坐标雷达ECCM技术研究

针对多功能三坐标雷达特点和电子对抗技术的发展,从反侦察和抑制干扰两个角度介绍了几种典型的雷达电子反对抗措施,最后又讨论了进一步提高雷达抗干扰能力的一些其他技术途径。     

一种快速机载无源定位方法的分析

提出一种快速无源定位技术,它得到目标位置的收敛时间大约为几十秒,对应的定位精度对２００ｋｍ以外的目标,可以达到位置误差的等效概率圆半径小于５～１０公里。分析了不同时间长度下的定位误差。     

舰载ESM设备的作战环境适应性分析

以舰载ESM所面临的多种作战环境的挑战为依据,对舰载ESM应具备的作战能力和一些关键问题进行了分析探讨,也提出了一些相应的解决途径,为舰载ESM设备的作战需求分析及试验评估提供一些思路和参考。     

基于脉冲样本图的机载RWR/ESM辐射源威胁评估

辐射源威胁评估是机载雷达告警器/电子支援措施(RWR/ESM)的重要功能,为了提高机载RWR/ESM设备应对复杂电磁环境的能力,建立了基于脉冲样本图的威胁评估专家系统,通过雷达威力模型确定了以脉冲样本图为输入的评估指标,运用TOPSIS方法,使得评估系统客观、有效,贴近电子战要求,符合机载RWR/ESM工作流程。仿真证明了评估系统的有效性及可行性。     

The psychology of psychiatric genetics: Evidence that positive emotions in females moderate genetic sensitivity to social stress associated with the BDNF Val??Met polymorphism.

Previous work indicated protective effects of positive emotions on genetically influenced stress sensitivity. Given the fact that expression of brain-derived-neurotrophic-factor (BDNF) is associated with stress-induced behavioral changes, it was hypothesized that the BDNF Val??Met genotype may mediate genetic effects on stress sensitivity, conditional on the level of concurrent positive emotions. Subjects (n = 446) participated in a momentary assessment study, collecting appraisals of stress and affect in the flow of daily life. Multilevel regression analyses examined moderation of daily life stress-induced negative affect (NA) by BDNF genotype, and to what degree this was conditional on concurrent positive emotions. Results showed that heterozygous BDNF "Met" carriers exhibited an increased NA response to social stress compared with "Val/Val" subjects. Positive emotions at the time of the stressor decreased BDNF genetic moderation of the NA response to social stress in a dose-response fashion. This effect was most pronounced in BDNF Met carriers. Thus, the impact of BDNF genotype on stress sensitivity is conditional on the experience of positive emotions. Interdisciplinary research in psychology and psychiatric genetics may lead to the improvement of treatment choices in stress-related disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

机载ESM与雷达航迹融合仿真系统研究

机载电子对抗侦察（ESM）和雷达已成为机载平台上获取目标信息的重要传感器。针对机载平台的特点模拟工程实践,从航迹配准、航迹关联和航迹融合三个阶段给出了一套仿真计算过程,构建了一个多参数航迹融合仿真模型。在航迹配准中主要考虑ESM传感器和雷达航迹数据之间的时空对齐问题,航迹关联中分析了基于统计理论的、基于模糊分析的和基于快速判别的三种航迹关联算法,在航迹融合中采用一种快速的加权融合的方法。仿真实验中给出了一种衡量不同航迹关联算法性能的评估计算方法,比较了在不同参数环境下三种航迹关联算法的性能及航迹融合的效果。最后给出了一些实验结论和工程实践性的建议,具有一定的工程参考意义。     

LTE系统中PDN连接过程的建立与实现

作为全IP化的LTE系统,接入分组数据网成为数据传输的重要手段.PDN连接过程是LTE通信系统接入分组数据网的一个重要过程,其目的是在UE和分组数据网络问建立一个默认承载.笔者通过对LTE终端协议栈结构的介绍,筛选出PDN连接过程涉及到的模块,提出了一种终端PDN连接过程的设计和实现的方法.使用TTCN测试工具对终端PDN连接过程的开发软件进行了测试与仿真,结果显示此过程完全符合LTE标准,验证了设计的正确性和可行性.     

使用ESM方位与多普勒频率量测的目标跟踪

针对ESM传感器能够同时测量方位角与多普勒频率的特点,提出了基于MGEKF的ESM多普勒频率/方位角目标跟踪算法(DB-MGEKF).与通常的纯方位角目标跟踪算法相比,DB-MGEKF算法增加了多普勒频率量测信息,并引入了能够较好处理系统非线性问题的修正增益扩展卡尔曼滤波器(MGEKF),从而提高了目标的估计精度及滤波...