基于机器视觉的车辆保险盒在线检测研究

摘要: 车辆保险盒作为汽车电控系统中的一个重要的元器件,其质量好坏直接影响汽车的性能,传统的车辆保险盒检测主要依靠人工检测,检测费时费力,针对该问题,提出一种基于视觉的车辆保险盒在线检测方法,分析了产品图像校正到标准模板图像的位置误差,采用SURF(Speeded Up Robust Feature)算法和平面单应性理论将待检产品图像变换到标准模板位置,利用颜色直方图匹配和模板匹配完成保险盒上元件的检测。实验结果证明,该方法检测效率高,稳定可靠,能够满足在线检测的要求,具有一定实用价值。     

Continuous-Wave Four-Wave Mixing via Electromagnetically Induced Transparency in Double-∧ Configuration

We investigate continuous-wave four-wave mixing via electromagnetically induced transparency in double-∧ con-figuration by using Schroedinger-Maxwell formalism. We derive the corresponding explicit analytical expressions.     

Bright Solitons in an Atomic Tunnel Array with Either Attractive or Repulsive Atom-Atom Interactions

Taking a coherent state representation, we derive the nonlinear Schroedinger-type differential-difference equations from the quantized model of an array of traps containing Bose-Einstein condensates and linked by the tunnelling process among the adjacent traps. It is shown that no matter whether two-body interactions among atoms are repulsive or attractive, a nearly uniform atom distribution can evolve into a bright soliton-type localized ensemble of atoms and a lump of atom distribution can also be smeared out by redistributing atoms among traps under appropriate initial phase differences of atoms in adjacent traps. These two important features originate from the tailoring effect of the initial phase conditions in coherent tunnelling processes, which differs crucially from the previous tailoring effect coming mainly from the periodicity of optical lattices.     

Deterministic Generation of Quantum State Transfer Between Spatially Separated Single Molecule Magnets

We propose a new scheme for realizing deterministic quantum state transfer （QST） between two spatially separated single molecule magnets （SMMs） with the framework of cavity quantum eleetrodynamics （QED）. In the present scheme, two SMMs are trapped in two spatially separated optical cavities coupled by an optical fiber. Through strictly numerically simulating, we demonstrate that our scheme is robust with respect to the SMMs＇ spontaneous decay and fiber loss under the conditions of dispersive SMMs-field interaction and strong coupling of cavity fiber. In addition, we also discuss the influence of photon leakage out of cavities and show that our proposal is good enough to demonstrate the generation of QST with high fidelity utilizing the current experimental technology. The present investigation provides research opportunities for realizing QST between solid-state qubits and may result in a substantial impact on the progress of solid-state-based quantum communications network.     

一种基于频率间插技术的DWDM-ROF系统

文章设计了一个基于频率间插复用的DWDM-ROF(密集波分复用—光载无线)系统,使每个信道载波与边带之间的空闲频段得到利用,从而提高了DWDM-ROF系统的频谱利用率.同时,为该系统设计了一种基于FBG(光纤布拉格光栅)的新颖的解复用器.数据传输的仿真实验不仅验证了该方法的可行性,还显示出了该系统具有良好的抗信道串扰能...     

Laser-polarization-dependent spontaneous emission of the zero phonon line from single nitrogen vacancy center in diamond

We investigate spontaneous emission properties and control of the zero phonon line （ZPL） from a diamond nitrogen- vacancy （NV） center coherently driven by a single ellipfically polarized control field. We use the Schrrdinger equation to calculate the probability amplitudes of the wave function of the coupled system and derive analytical expressions of the spontaneous emission spectra. The numerical results show that a few interesting phenomena such as enhancement, narrowing, suppression, and quenching of the ZPL spontaneous emission can be realized by modulating the polarization- dependent phase, the Zeeman shift, and the intensity of the control field in our system. In the dressed-state picture of the control field, we find that multiple spontaneously generated coherence arises due to three close-lying states decaying to the same state. These results are useful in real experiments.     

基于SOA-XGM的对称型UWB信号光学产生的研究

文章提出了两种利用SOA(半导体光放大器)的XGM(交叉增益调制)和FBG(光纤布拉格光栅)光学生成对称型UWB(超宽带)信号的新方法.分析了该方法的工作原理并进行了仿真实验,分别得到了符合FCC(美国联邦通信委员会)标准的中心频率为5.35 GHz、相对带宽为114％以及中心频率为4.7 GHz、相对带宽为132％的...     

Deterministic generation of Greenberger-Horne-Zeilinger and W states for three distant atoms via adiabatic passage

We propose two schemes for generating Greenberger-Horne-Zeilinger and W states of three distant atoms.In the present schemes,the atoms are individually trapped in three spatially separated optical cavities coupled by two optical fibres.Performing an adiabatic passage along dark states,the population of cavities and fibres excited is negligible under certain conditions.In addition,the spontaneous decay of atoms is also efficiently suppressed based on our proposals.Furthermore,the discussion about the entanglement fidelity is given and we point out that our schemes work robustly with small fluctuations of experimental parameters.     

一种新型的高容量光互连架构

光互连具有低功耗、大带宽等优越性能,可以实现数据中心节点数与交换容量的大幅增大.提出了一种基于阵列波导光栅(AWGR)的新型大容量光互连架构,通过可调波长转换器与AWGR提供波长路由,并利用分布式控制实现快速配置与低延迟.无缓冲的光交换机可能产生数据包争用,基于光纤延迟线的光缓冲可用于争用解决.详细描述了分别适用于严格...     

基于光纤XPM光学生成UWB信号的方法

提出了一种基于色散位移光纤(DSF)的交叉相位调制(XPM)效应的超宽带(UWB)光学生成方法。该方法首先利用DSF的XPM效应实现高功率的高斯泵浦光对低功率的直流探测光的交叉相位调制,然后利用光纤布拉格光栅(FBG)对探测光进行鉴频,实现相位调制到强度调制的转换,从而获得单周期UWB信号。利用光子仿真软件对方案进行了仿真实验,得到了中心频率分别为7GHz和6.95GHz、相对带宽分别为143%和145%的UWB信号,验证了所提方法的可行性。同时,研究了输入信号脉冲宽度、FBG的反射率、鉴频器的类型对产生的单周期UWB脉冲信号波形和频谱的影响。仿真实验的结果表明,该方案对输入信号脉冲宽度不是过宽的情况下具有良好的容忍度,光学高斯带通滤波器、波分复用器和FBG等光滤波器均可作为鉴频器,采用FBG优点是可通过改变反射率灵活地调整产生的UWB脉冲信号的波形。