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基于Comsol Multiphysics无限长圆柱载流导线产生的磁场分布研究 总被引:1,自引:0,他引:1
介绍一种基于Comsol Multiphysics软件的工程电磁场仿真方法。以无限长圆柱载流导线产生的磁场分布为例,在理论计算的基础之上,给出了基于Comsol Multiphysics软件的仿真过程。并对比分析了理论计算值和仿真结果。证明了Comsol Multiphysics软件是一款功能强大,操作简单,计算精度高的工程电磁场仿真软件。 相似文献
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为了满足多领域中水下复杂环境声压检测的需要,提出了一种基于微机电系统(MEMS)的电容式声压水听器,开发出注油孔及注油沟道设计,将传感器封装于硅油中,通过平衡振动薄膜内外压强可以提高其耐受静水压能力。使用Comsol Multiphysics仿真软件对水听器建模,采取热粘性声-结构多物理场对传感器进行静态分析、模态分析及谐波声信号扰动下的灵敏度分析,在用有限元法分析模型时考虑了热效应与粘滞效应对小尺寸声学换能器的影响,使仿真结果更具说服力。得到了在幅值为10 Pa,频率在1 Hz~10 kHz的谐波声信号扰动下水听器的接收灵敏度为-147 dB。仿真结果表明,设计的电容式声压水听器据有高灵敏度和宽频带等特点,可以满足不同领域对水下低频声压信号的测量需求。 相似文献
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针对目前电容层析成像(ECT)技术在管道流体监测方面存在的中心部位的信噪比低、边缘效应大以及识别精度低的缺点,提出一种双电压激励方法来提高检测区域中心的检测信号强度。采用软件COMSOL Multiphysics建立了一16电极外置传感器的有限元模型,分别采用传统的单电压激励法和本文提出的双电压激励方法对有限元模型进行仿真分析,并通过试验进行对比,结果表明:相对传统的单电压激励方法,双电压激励法能够改善管内区域的电场和电势分布均匀性,提高管内中心区域的检测信号强度及灵敏度水平,从而提高了对管内流体监测的识别精度。 相似文献
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增大传感器振子的质量和静态测试电容可以减小电容式MEMS惯性传感系统的噪声,而深度粒子反应刻蚀工艺由于复杂的工艺原因,当深宽比较大时,不能刻蚀出大质量和大初始电容的传感器.据此,本文研究了一种磁驱动增大检测电容的MEMS惯性传感器,通过电磁驱动器,传感器的静态测试电容可以大幅增加,在梳齿电容上刻蚀阻尼槽后,其机械噪声达到0.61μg每根号赫兹,仿真其共振频率为598Hz,静态位移灵敏度为0.7μm每重力加速度,基于硅 玻璃键合工艺,制作了栅形条电容式惯性传感器,并用电磁驱动的方式测试其品质因子达到715,从而验证了制作工艺的可行性和电磁驱动器改变传感器初始静态测试电容的可行性. 相似文献
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微电容传感器检测电路是微电容传感器中的关键技术,由于微电容传感器的电容变化量很小,电路中的杂散电容对传感器的影响就会非常大,所以微电容测量电路必须具备大动态范围、高测量灵敏度、低噪声、抗杂散性好等性能。因此提出了电桥式交流电容检测电路。首先将转换后的电压信号加载到高频正弦激励信号中,然后通过放大等一系列处理得到输出电压,最后根据待测电容与输出电压的关系得到待测电容的容抗。(1)采用Multisim仿真软件对提出的电桥式交流电容检测电路进行了调试及可行性验证。(2)在设计的基础上对电路进行了实物焊接和调试。(3)利用信号发生器和示波器对一批已调试的微电容进行了实验验证。实验结果表明,提出的电桥式交流电容检测电路测量的输出电压与理想情况下的输出电压基本一致?且该电路能很好地抑制寄生电容的影响,有良好的线性和稳定性。 相似文献
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GU Min-fen LIANG Zhong-cheng WANG Ren-zhou DONG Xiang-mei ZHANG Pei-ming CHEN Jia-bi 《光电子快报》2008,4(2):150-152
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
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R.Pelzer P.Lindner T.Glinsner B.Vratzov C.Gourgon S.Landis P Kettner C.Schaefer 《半导体技术》2004,29(7):86-91
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
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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
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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
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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
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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
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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
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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
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Thomas M.Trexler 《半导体技术》2004,29(5)
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. 相似文献
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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. 相似文献