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71.
介绍了计算伏秒消耗的玻印亭方法,并通过扫描等离子体电流爬升率对伏秒消耗进行了优化分析。分析结果对EAST装置长脉冲稳态放电提供一定的参考。 相似文献
72.
Haibo Peng Boyu Wu Qiong Song Fei Lu Shuyun Luo 《International Journal of Infrared and Millimeter Waves》2003,24(9):1587-1596
Hybrid electrode combined coplanar waveguide (CPW) and microstrip lines in ultra-broadband electro-optic modulators. The characteristics of the modulators with hybrid electrode is like that of the modulator with the microstrip lines, in which the microstrip electrode is loaded above only one arm of Mach-Zehnder (M-Z) optical waveguide, besides the problem of microstrip line to coaxial transition and corona polarization in polymer modulators have been best solved at the same time. By using finite element method (FEM), the characteristic parameters such as half-wave voltage, modulation bandwidth characteristic impedance, effective microwave refractive index of polymer modulators with microstrip line and hybrid electrode are analysed and compared in this paper. The results present that velocity match, impendence match and lower microwave propagating loss is easily realized in modulators with hybrid electrode. 相似文献
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Min Zhang Aanying Ma Lu Bai Lewei Li Zhensen Wu 《International Journal of Infrared and Millimeter Waves》2005,26(5):701-713
We present an effective numerical technique to characterize the scattering of wide-slot antennas fed by waveguides with arbitrary terminations in terms of the method of moment (MoM) and the mixed potential integral equation (MPIE). In particular, the precorrected-fast Fourier transform (P-FFT) eliminates the need to generate and store the usual square impedance matrix andthus leads to speed up the matrix-vector multiplication in the resultant system. This property makes the Rao-Wilton-Glisson (RWG) functions to be useful in simulating electrically large-scale problems. In addition, the scattering from the finite ground surfaces is accounted for in the total scattered field by using the method of equivalent edge currents. The numerical results are presented and compared with both the traditional method of moment results obtained using the entire-domain basis functions and the experimental results, to demonstrate the proposed method to be a good candidate for study on the scattering of arbitrary wide-slot large array. 相似文献
75.
《Journal of Electrostatics》2014,72(2):99-106
Numerical modeling of corona discharges has followed the same set of procedures for many years. Corona discharges on large scales are modeled only for ion drift, neglecting ionization. Studies of the ionization zone are often conducted in uniform axisymmetric configurations. However, in configurations that induce non-uniform electric fields, a combination of the two procedures is necessary to accurately capture the discharge physics and ion distribution. The present study conducts numerical simulations of a wire-cylinder corona using both the models and demonstrates the necessity of including the ionization physics to obtain improved accuracy, particularly in the presence of non-uniform electric fields. 相似文献
76.
分析了CCD非线性产生的原因,提出了CCD非线性校正的新方法——多点多段线性逼近法.给出了CCD非线性产生及校正方法的简单公式推导及物理解释.通过计算机模拟和实验进一步验证了CCD非线性校正之后,明显地减小了γ级频谱的产生.模拟情况下物体面形恢复后的标准偏差明显减小:未校正时为0.040 7 mm,校正之后时为0.025 2 mm;实验情况下校正之后的物体恢复面形效果明显优于未校正时的效果. 相似文献
77.
《Current Applied Physics》2015,15(5):622-631
Lithium (Li) (0–5 wt%) doped V2O5 thin films were spray deposited at 450 °C onto ITO substrates. Structural analysis using X-ray diffraction and Raman spectroscopy revealed orthorhombic phase of the films. In addition to the V2O5 phase, presence of VO2 peaks due to high deposition temperature is also evident from structural and optical characterization. The non-stoichiometric nature of the films due to loss of the terminal O atom was confirmed from Raman spectroscopy. The direct band gap, indirect bandgap, and phonon energies were also calculated from optical studies. Different charge states of vanadium ions present in the film were identified from X-ray photoelectron spectroscopy study. Results from cyclic voltammetry experiments reflected significant differences between the undoped and Li doped V2O5 samples. Transport properties by Hall-effect measured at room temperature indicated significant increase in conductivity, carrier concentration and mobility of V2O5 thin films on doping with Li. A Dye Sensitized Solar Cell (DSSC) was fabricated using mobility enhanced 5 wt% Li doped V2O5 film as photoanode and its efficiency was found to be 2.7%. A simple electrochromic cell is fabricated using undoped V2O5 thin film to demonstrate the colour change. 相似文献
78.
近红外拓扑方法在南疆红枣品质分析中的应用 总被引:2,自引:0,他引:2
从南疆红枣的物理和光谱特征两方面,通过反复调整和逐步细分相结合的方法,给出红枣品质细分和特征因子分析框图。实际应用中可依据不同需要设置最佳光谱参数来提高光谱重复性和质量。实验分离出南疆红枣常见的裂口褐变、色泽和成分等光谱特征因子,如褐变特征因子明显尖峰特征谱线位置10 170cm-1。通过光谱图的特征分析,初步建立了红枣近红外光谱和部分品质之间的对应关系,为下一步红枣品质编码奠定了基础。该方法可节省大量重复建模费用,在建立红枣近红外品质分析标准和模型库共享方面有较好的应用前景。 相似文献
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