红外激光成像中的弱小目标的准确定位技术研究

由于红外激光成像中的弱小目标,存在信噪比低、无纹理信息和信号弱的特征,使得传统基于背景抑制的目标检测方法,无法将目标从复杂的背景中分割出来,检测准确率低。因此,将基于尺度空间的红外弱小多目标检测算法应用于红外激光成像中弱小目标的定位中,给出了红外激光成像中弱小目标定位硬件总体结构,其由传输控制模块、图像采集模块和弱小目标定位模块组成。采用传输控制模块TMS320F2812传递和处理系统中的图像,依据中央控制单元的命令对红外摄像机进行控制,通过核心芯片为XC95288XL的图像采集模块获取弱小目标图像,依据一定的字节顺序保存在RAM中。通过软件设计中的基于尺度空间的红外弱小多目标检测算法,完成弱小目标的准确定位。实验结果表明,该算法可在不同背景环境中,有效过滤干扰区域,准确检测出实际弱小目标,鲁棒性较高。     

背景自适应的多特征融合的弱小目标检测

针对红外复杂背景下的弱小目标检测难题,提出一种基于背景自适应的多特征融合的复杂背景下弱小目标的检测算法。首先,通过对红外图像进行空域滤波去除孤立噪声点,并利用恒虚警率分割消除大面积平稳背景,获得疑似目标集。然后融合红外图像的背景信息、弱小运动目标的灰度特征、目标与周围像素的方向梯度特征等多个典型特征,消除疑似目标集中的大部分假目标,最后运用运动特征获取真实目标的轨迹,最终实现复杂背景下的红外弱小目标的检测。实验表明:该算法能实现复杂背景下低信噪比的红外弱小目标快速检测,具有检测概率高,算法速度快,鲁棒性好的特点。     

基于蜕化决策树的红外目标检测

针对复杂背景下单帧红外图像中的弱小目标检测的问题,提出一种基于蜕化决策树的检测算法。该算法通过提取红外小目标梯度对比度、邻域灰度分布等多个统计特征,充分利用了各个特征的互补作用,达到了高检测概率和低虚警率。通过对实测数据进行仿真,结果表明该方法能有效检测红外弱小目标。     

基于光谱尺度空间与管道滤波的红外目标检测

为了准确地从复杂干扰背景下检测出真实弱小目标,本文引入视觉显著性,设计了基于快速光谱尺度空间与动态管道滤波的红外目标检测算法。基于真实目标与背景内容之间的整体差异,引入快速光谱尺度空间与阈值分割技术,设计视觉显著性机制,对红外图像完成处理,输出全局显著性映射,以高效过滤干扰背景内容。考虑目标与背景的局部特征差异,构建自适应局部对比度增强机制,对粗检测结果实施处理,获取对应的局部显著性映射,改善视觉显著性区域内目标的对比度。引入高斯差分理论,通过估算每一帧红外图像中的目标像素直径,形成动态管道滤波,充分消除虚警,准确识别出弱小目标。多组实验数据显示：较已有的红外目标检测技术而言,在各种不同的复杂背景干扰下,所提算法呈现出更好的检测能力,拥有更理想的接收机工作特性(ROC)曲线。     

基于多向差异度的红外弱小目标检测算法

在分析红外图像中弱小目标的特征后,针对目前经典的红外弱小目标检测算法性能不足的问题,提出了一种基于多向差异度的红外弱小目标检测算法.该算法利用待检测像素点在各方向上的差异度来判决其是否为目标,无需背景预测、图像增强等处理,因此其构造简单,计算量小,易于实现,并能有效改善复杂背景环境下红外弱小目标的检测性能.通过大量的仿真实验证明了该算法的有效性和优越性.     

利用局部灰度特征分析实现红外弱小目标检测

提出了一种利用局部灰度特征分析进行红外弱小目标检测的新方法.该方法通过判断图像局部灰度包络曲面是否具备二维高斯函数曲面特征实现红外弱小目标检测,不需要进行传统的背景预测.设计了新的目标局部灰度特征提取方法和适合工程计算的自动目标检测算法.实验结果证明了算法参数选择策略的有效性,验证了算法对复杂背景边缘良好的杂波抑制能力...     

采用尺度空间理论的红外弱小目标检测方法

为了检测红外场景中尺寸大小变化的弱小目标,针对传统滤波方法中固定大小滤波核对此类特性目标检测表现出的不足,提出一种基于尺度空间理论的红外弱小目标检测方法。首先对弱小目标特性进行分析,提出采用点扩散函数形式的目标模型来描述弱小目标;采用固定自适应邻域的方法对原始红外图像进行预处理,抑制背景杂波,增强目标能量;依据尺度规范化后的拉普拉斯尺度空间对图像不同元素滤波响应的不同,获取图像中的可疑目标,利用可疑目标点与其周围像素的梯度关系得到可疑目标点的中心坐标,并据此得到其在图中的尺寸大小;对每个可疑目标划分一个自适应大小窗口,获取分割阈值,分割出真实目标。实验结果表明,该方法能较好地检测出弱小目标,且具有较低的虚警率。     

基于注意力机制的复杂背景下红外弱小目标检测方法研究

针对复杂场景下红外图像中弱小目标像素占比少、特征细节不明显致使目标特征提取困难、检测准确率低的问题，提出了一种基于注意力机制的复杂背景下红外弱小目标检测方法。该方法以YOLOv5网络为基础，设计SimAMC3注意力机制模块，优化网络的特征提取层；设计目标检测头，通过增加特征融合层来改变其开始进行特征提取的深度，获得新的弱小目标检测层，使浅层特征层更好地保留弱小目标的空间信息；改进预测框筛选方式，提高距离相近或重叠目标的检测精度。实验选取了两个SIRST红外弱小目标图像数据集，对其进行标注并训练。实验结果表明，改进后的算法与原YOLOv5算法相比，平均精度均值（mAP）分别提升了4.8%和7.1%，在不同复杂背景下均可有效检测出红外弱小目标，体现了良好的鲁棒性和适应性，可以有效应用于复杂背景中的红外弱小目标检测。     

基于光流估计的红外弱小运动目标检测

提出了一种对复杂云层背景下红外图像序列中弱小运动目标分割和检测的方法.首先,利用Hom-Schunck算法计算序列图像的光流场,然后利用阙值分割和数学形态学滤波的方法进行目标检测,滤除噪声后提取出背景中的运动目标.实验结果表明,该算法对实时检测在复杂背景的红外图像中运动的弱小目标具有很好的效果.     

基于FPGA的红外弱小目标检测算法

传统的红外弱小目标检测算法一般采用DSP(digital signal processing)处理器实现,算法复杂且实时性差,本文提出了一种基于FPGA(field programmable gate array)的自适应阈值的FAST(features from accelerated segment test)算法对红外弱小目标进行检测,利用FPGA并行处理的特点,采用流水线设计实现了算法的硬件加速.改进的自适应阈值方法可以根据不同的环境生成合适的阈值,避免了由于阈值选择不当造成的红外弱小目标的丢失或冗余.最后采用4组不同的实测红外图像进行实验,结果表明:该算法能实时地检测出红外图像中的弱小目标,并且能够取得较高的检测率和较低的虚警率,满足实时性和有效性的要求.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks