光电对抗技术和装备现状评析

介绍了光电对抗技术和装备的现状,对光电对抗技术、光电干扰技术、光电隐身技术进行了综述,并对未来光电对抗技术发展趋势进行了预测。     

PCI接口卡硬件与驱动程序设计

介绍了一种较为通用的PCI接口卡的硬件结构,说明了硬件设计的几种可行性方案和硬件设计时需要注意的问题,同时详细地阐述了PCI设备WDM驱动程序开发的基本方法,比较了几种常用开发工具的优缺点,并对驱动程序中的PCI设备I／O端口与存储器的读写、中断处理以及应用程序与驱动程序之间多种通信方式作了详细的介绍。     

检测中断后机载雷达航迹连续跟踪算法

雷达检测数据的连续性对于雷达航迹跟踪来说是非常重要的,根据观测目标特性的不同,中断检测时长不同会造成不同程度的航迹误跟、漏跟甚至失跟。分析了在某些特定情况下出现雷达检测中断后对航迹处理造成的影响,针对常规航迹跟踪处理方法,从原理上对中断检测对航迹连续带来的问题进行了详细分析,设计并实现了一种检测中断前后航迹连续跟踪算法,获得了较为满意的效果,并通过仿真和实测数据的处理验证了方法的有效性。     

中小软件项目中基于敏捷过程域控制的QA外包探索

软件的质量管理是控制软件品质乃至项目品质的重要手段,但企业在建设中小型软件项目时,极易受到条件的制约而无法控制项目的质量.将质量保证(QA)外包给第三方评估机构,通过实施SSTL设计搭建的轻载质量管理框架SQAF,约束质量管理过程中关键过程域,既能保证中小型软件项目运行的过程受控,又能避免重载质量体系对项目的繁琐制约.     

温室大棚卷帘机无线远程控制系统的设计

针对目前温室大棚卷帘机存在一定安全隐患,为实现温室大棚卷帘机的自动升降,采用GSM技术和计算机控制技术,利用现有的移动网络平台,设计了一套远程无线卷帘机控制系统。通过试验证明,本系统稳定性高,价格低,真正实现了对温室大棚卷帘机的远程控制。     

静止图像的信息隐藏容量研究

信息隐藏容量的计算和估计是信息伪装领域中的最困难问题之一。该文从编码和集合论的角度考察了离散情形下静止图像的信息隐藏容量的计算和性质,给出了相关的定义和计算方法,并给出了在无攻击者条件下静止图像的信息隐藏容量只与失真限制和图像数据源的概率分布有关的结论。进一步,还给出了有攻击者情形下的隐藏容量的相关结果。     

基于卷积码的DFT-S-GMC系统迭代检测算法

针对基于离散傅立叶变换扩频的广义多载波系统(DFT-S-GMC),提出一种新的迭代检测方法.该方法基于DFF-S-GMC系统的频域收发结构,并根据线性最小均方误差(LMMSE)检测所得发送符号的后验均值和方差来表征其统计概率分布,从而完成检测器和译码器的信息传递.仿真结果表明,所提出迭代检测接收算法的性能明显优于传统的非迭代检测接收算法,并且在卷积码下的迭代检测性能超过了Turbo码下的非迭代检测性能,而其实现复杂度则有较大降低.     

Analysis of FMRI data using an integrated principal component analysis and supervised affinity propagation clustering approach

Clustering analysis is a promising data-driven method for analyzing functional magnetic resonance imaging (fMRI) time series data. The huge computational load, however, creates practical difficulties for this technique. We present a novel approach, integrating principal component analysis (PCA) and supervised affinity propagation clustering (SAPC). In this method, fMRI data are initially processed by PCA to obtain a preliminary image of brain activation. SAPC is then used to detect different brain functional activation patterns. We used a supervised Silhouette index to optimize clustering quality and automatically search for the optimal parameter p in SAPC, so that the basic affinity propagation clustering is improved by applying SAPC. Four simulation studies and tests with three in vivo fMRI datasets containing data from both block-design and event-related experiments revealed that functional brain activation was effectively detected and different response patterns were distinguished using our integrated method. In addition, the improved SAPC method was superior to the k -centers clustering and hierarchical clustering methods in both block-design and event-related fMRI data, as measured by the average squared error. These results suggest that our proposed novel integrated approach will be useful for detecting brain functional activation in both block-design and event-related experimental fMRI data.     

Nanowire Assisted Mechanotyping of Cellular Metastatic Potential

Nanotechnology has provided tools for next generation biomedical devices which rely on nanostructure interfaces with living cells. In vitro biomimetic structures have enabled observation of cell response to various mechanical and chemical cues, and there is a growing interest in isolating and harnessing the specific cues that 3D microenvironments can provide without the requirement for such culture and the experimental drawbacks associated with it. Here, a randomly oriented gold coated Si nanowire substrate with patterned hydrophobic–hydrophilic areas for the differentiation of isogenic breast cancer cells of varying metastatic potential is reported. When considering synthetic surfaces for the study of cell-nanotopography interfaces, randomly oriented nanowires more closely resemble the isotropic architecture of a natural extracellular matrix. In the study reported here, the authors show that primary cancer cells preferably attach to the hydrophilic region of randomly oriented nanowire substrate while secondary cancer cells do not adhere. Using machine learning analysis of fluorescence images, cells are found to spread and elongate on the nanowire substrates as compared to a flat substrate, where they mostly remain round. Such platforms can not only be used for developing bioassays but also as stepping stones for tissue printing technologies where cells can be selectively patterned at desired locations.     

Immunoregulation of Macrophages by Controlling Winding and Unwinding of Nanohelical Ligands

Developing materials with the capability of changing their innate features can help to unravel direct interactions between cells and ligand-displaying features. This study demonstrates the grafting of magnetic nanohelices displaying cell-adhesive Arg-Gly-Asp (RGD) ligand partly to a material surface. These enable nanoscale control of rapid winding (“W”) and unwinding (“UW”) of their nongrafted portion, such as directional changes in nanohelix unwinding (lower, middle, and upper directions) by changing the position of a permanent magnet while keeping the ligand-conjugated nanohelix surface area constant. The unwinding (“UW”) setting cytocompatibility facilitates direct integrin recruitment onto the ligand-conjugated nanohelix to mediate the development of paxillin adhesion assemblies of macrophages that stimulate M2 polarization using glass and silicon substrates for in vitro and in vivo settings, respectively, at a single cell level. Real time and in vivo imaging are demonstrated that nanohelices exhibit reversible unwinding, winding, and unwinding settings, which modulate time-resolved adhesion and polarization of macrophages. It is envisaged that this remote, reversible, and cytocompatible control can help to elucidate molecular-level cell–material interactions that modulate regenerative/anti-inflammatory immune responses to implants.