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181.
HDMI(High—Definition Multimedia Interface)接口标准自2003年发布以来取得了巨大成功,截止至2009年4月的6年间,已有850位授权采用者。据产业研究机构In-Stat预测,到2012年,装有HDMI接口设备的出货量将超过600,000,其中数字电视、机顶盒、DVD播放器、蓝光播放器和PC将成为HDMI的主流应用。 相似文献
182.
Ching-Chung Yang 《Optik》2011,122(18):1684-1687
We demonstrate a novel method to modify the mask-filtering approach by enlarging the gray-level difference of any two nearby pixels in an image. Derivatives are calculated in different directions respectively instead of isotropically. Some higher spatial frequencies are then selectively magnified. The final image has better sharpened fine characteristics than that enhanced by the conventional technique. 相似文献
183.
Two novel fluorescent calix[4]arene derivatives 1a and 1b with benzoxazole or benzothiazole units in 1,3-alternate conformation have been synthesized and characterized by IR,~1H NMR,~(13)C NMR and MS.Their complexation properties to different heavy and transition metal ions have been studied by UV-vis spectroscopy and fluorescence spectrometer.Compounds 1a and 1b show selective recognition to Fe~(3+) and Cr~(3+). 相似文献
184.
In this paper, the root mean square (rms) technique is applied in order to reduce the non-coherent noise in phase-contrast image. The proposed technique is applied to a sample of 200 μm step height nominally. The recorded off-axis interferograms generated from two different wavelengths are processed to obtain an object wave (amplitude and phase) for each wavelength separately. The independent phase maps are subtracted and a phase map for the beat-wavelength is obtained and converted to height map. The rms values of 10 pixels profiles from the obtained height map are calculated automatically to show the three-dimensional (3D) profile. The experimental results show that the non-coherent noise is reduced by the order of 90% when the rms technique is applied and the uncertainty in measurement has been found to be of the order of 1.5 μm. The proposed technique can provide a simple and real solution for measuring 3D objects having high abrupt height difference. 相似文献
185.
186.
In this research we address in detail a mode III radial matrix crack penetrating a circular inhomogeneity. One tip of the radial crack lies in the matrix, while the other tip of the radial crack lies in the circular inhomogeneity. In addition the two tips of the crack are mutually image points (or inverse points) with respect to the circular inhomogeneity-matrix interface. First we conformally map the crack onto a unit circle Ca in the new ζ-plane. Meanwhile the inhomogeneity-matrix interface is mapped onto Cb, a part of another circle in the ζ-plane. In addition Ca and Cb intersect at a vertex angle π/2. By using the method of image in the ζ-plane, closed-form solutions in terms of elementary functions are derived for three loading cases: (1) remote uniform antiplane shearing; (2) a screw dislocation located in the unbounded matrix; and (3) a radial Zener–Stroh crack. 相似文献
187.
Gong Xing 《电子科学学刊(英文版)》2001,18(2):181-184
A trust region method is proposed to solve the problem of microwave tomography, which is very difficult to be solved for its ill-posedness and nonlinearity. Compared with the Levenberg-Marquardt method, this method introduces more a priori knowledge and might obtain better results, though the two methods are equal in some cases. 相似文献
188.
本文对第19届国际高速摄影与光子学会议做了简介,主要谈到了光机式相机、高速视频技术、全息和干涉计量。 相似文献
189.
A fast iterative scheme for multilevel thresholding methods 总被引:1,自引:0,他引:1
The previously published optimal thresholding techniques based on some objective functions are very efficient in the bi-level thresholding case, but they are impractical when extended to multilevel thresholding. The reason for this is their computational complexity which grows exponentially with the number of thresholds. In this paper, an iterative scheme is proposed to render these optimal thresholding techniques more practical. The proposed algorithm starts with a bi-level thresholding, then uses the initial results to obtain higher-order thresholds. This algorithm is iterative and the convergence is proved. We also introduce some useful programming techniques to make the computation more efficient. The proposed algorithm can therefore determine the number of thresholds automatically as well as save a significant amount of computing time. 相似文献
190.
磁场渗透导体壳的实验研究 总被引:2,自引:2,他引:0
本文叙述了测量阶跃脉冲垂直磁场和水平磁场渗透HL-1装置各种比例导体壳时间常数的方法。对空芯和铁芯变压器情况分别做了实验。给出了相应结果。 相似文献