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1.
麻醉深度监测对提高麻醉质量,保障患者的手术期安全与康复具有极为重要的意义。系统地回顾了脑电信号分析算法,主要包括脑电双频指数、麻醉趋势指数、脑状态指数等多种不同参数的算法在麻醉深度监测中的应用研究及进展情况。首先比较了这些参数的脑电分析算法在临床应用中的优缺点,接着提出了具有优秀去噪能力的排序熵指数算法,并引入反向映射神经网络对脑电双频指数、麻醉趋势和排序熵指数进行校正优化,以便更精确地实现麻醉深度监护。最后展望了今后其应用于麻醉深度监测领域的发展前景。  相似文献   

2.
针对中国公路建设的高速发展,公路照明的电力消耗越来越大,为了同时满足照明节能与行车安全的需求,结合网络视频监控系统,提出了一套基于车辆检测技术的公路照明节能系统方案.系统前端采用嵌入式平台,分析并移植MJPG-Streamer视频流服务器,完成视频的采集传输和路灯驱动电路的设计.设计了一种基于车灯特征识别的车辆检测算法,根据检测到车辆的有无,自动控制路灯的开闭,实现路灯的智能节能控制.并且通过QT设计的人机交互界面,可按需强制控制路灯的开闭.通过实验测试,系统运行稳定,完成了预设的功能,具有很好的应用前景.  相似文献   

3.
本文采用随机等效采样方法,实现实时40MHz等效4GHz的采样速率.系统在可编程逻辑器件CPLD的时序控制下有序工作,DSP完成数据处理,处理结果通过USB总线送往主机.前端信号调理电路的设计、双斜率时间展宽电路的设计、等效排序算法的设计是设计的关键点所在.  相似文献   

4.
盲解调系统能够在未知调制方式的条件下完成信号解调,在认知无线电、电子对抗等领域具有重要的应用价值。现有的盲解调系统,大多调制方式识别精度低,容易产生解调错误,且受硬件平台限制,拓展性较差。本文设计并实现了一套基于深度学习和软件无线电的盲解调系统。该系统利用最新的深度学习算法替代传统的基于特征的算法,用于提高调制方式识别精度;同时,还采用软件无线电平台替代传统的硬件电路,便于系统功能的升级和扩充。测试结果表明,本文实现的系统达到了设计需求,在各种场景下均能正确解调信号,且能够对调制方式的改变及时作出反应。   相似文献   

5.
以Xilinx公司的V5系列FPGA芯片为研究对象,设计实现了一种基于VPX标准的6U射频收发前端信号处理系统。该系统主要由控制电路和射频电路组成,控制电路主要完成对外、对内的接口通信功能以及核心器件的控制。射频电路主要完成信号滤波、放大、正交上变频、功率放大等。设计的系统支持串行Rapid IO高速数据传输,为数据的高速交换提供了可能,满足了系统对带宽和数据处理能力的要求,经过验证系统的各项性能指标符合设计要求。  相似文献   

6.
庄子源  班恬 《电讯技术》2021,61(7):833-838
为了及时获取航迹信息,基于射频前端芯片AD9361以及基带数据处理芯片Zynq-7000设计了一种对广播式自动相关监视(Automatic Dependent Surveillance-Broadcast,ADS-B)信号解调的软件无线电接收系统,给出详尽的硬件框架设计,进行了Linux平台搭建,并完成了AD9361寄存器配置工作.经测试,在信噪比6 dB以上时,接收系统的检测概率超过60%;实际监测中,接收系统成功接收并解调信噪比为4.4 dB的ADS-B短报文信号.据此,此接收系统可被认为是一种性能良好的ADS-B信号接收系统.  相似文献   

7.
在现代复杂电子系统中,机内测试(BIT)技术作为提高系统可维修性和可测试性的重要手段,日益得到普遍重视和广泛应用。根据设计原则,BIT系统采用多机分布式结构,故障检测电路和故障检测软件采用通用化设计,故障定位采用基于故障传播有向图的故障定位方法。本文对雷达设备的维修性及状态监测方面进行了探索,主要阐述了机内测试系统的实现结构及其基于故障树算法实现故障定位的原理,介绍了通用故障检测电路的工作原理,总结了设计过程中应注意的问题及相应的解决方法。  相似文献   

8.
本文基于SMIC 40nm LL CMOS工艺对一款256Kb的低电压8T SRAM芯片进行测试电路设计与实现,重点研究低电压SRAM的故障模型和测试算法,并完成仿真验证与分析。电路主要包括DFT电路和内建自测试电路两部分,前者针对稳定性故障有着良好的覆盖率,后者在传统March C+算法基础上,提出了一种新的测试算法,March-Like算法,该算法能够实现更高的故障覆盖率。仿真结果表明,本文设计的DFT电路能够减小稳定性故障的最小可检测电阻,提高了稳定性故障的测试灵敏度;March-Like算法可以检测到低电压SRAM阵列中的写破坏耦合故障、读破坏耦合故障和写干扰故障。  相似文献   

9.
张燕子 《电视技术》2021,45(8):146-149,153
深度学习作为机器学习技术的拓展,凭借其自身强大的数据处理能力,在图像处理和语音识别等方面表现出色.在软件安全领域,恶意软件的威胁是软件领域主要安全风险之一,可以利用深度学习算法有效提升恶意软件的检测效率.基于此,分析传统和基于深度学习的恶意软件检测方法,验证了在传统的分析方式下融入深度学习模型框架,可以在大量恶意样本中训练出较好的检测模型,同时讨论了未来软件安全可能面临的主要挑战.  相似文献   

10.
混合式IRFPA读出电路参数测试系统   总被引:8,自引:0,他引:8       下载免费PDF全文
读出电路是红外焦平面阵列(IRFPA)的关键组成部分之一。它的质量直接影响到IRFPA的质量,因此读出电路参数的测试非常重要。本系统采用信号模仿的方法,对IRFPA读出电路注入电信号,调节电信号即可模拟不同的测试条件,利用读出电路的输出就可测试其主要参数的技术指标。系统采用虚拟仪器系统的精密数据采集卡(DAQ)和用于数据处理的软件(LabVIEW)来构建出混合式IRPFA读出电路参数测试系统。采集卡对读出电路输出信号进行采集,并利用软件的运算功能模块对采集的数据进行统计运算,就可定量得到各项参数指标,从而判断读出电路性能的好坏。采用本系统对128×128元读出电路进行测试,实验结果表明了系统的可行性,测试结果可以反映读出电路的质量。  相似文献   

11.
Waveguide multilayer optical card (WMOC) is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling & processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic (VB) language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.  相似文献   

12.
IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…  相似文献   

13.
The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.  相似文献   

14.
Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.  相似文献   

15.
A doping system consisting of NPB and PVK is employed as a composite hole transporting layer (CHTL). By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK : NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK : NPB at 1:3.  相似文献   

16.
An insert layer structure organic electroluminescent device(OLED) based on a new luminescent material (Zn(salen)) is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn(salen)/Liq/LiF/A1/CuPc/NPD/Zn(salen)/Liq/LiF/A1. Effective insert electrode layers comprising LiF(1nm)/Al(5 nm) are used as a single semitransparent mirror, and bilayer cathode LiF(1 nm)/A1(100 nm) is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.  相似文献   

17.
Due to variable symbol length of digital pulse interval modulation(DPIM), it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation(FDPIM) method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.  相似文献   

18.
It is a key problem to accurately calculate beam spots' center of measuring the warp by using a collimated laser. A new method, named double geometrical center method (DGCM), is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device (CCD) is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What's more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.  相似文献   

19.
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.  相似文献   

20.
High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET > PDMAT > TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.  相似文献   

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