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961.
针对常规综合鉴别函数制作的复合匹配滤波器,对不同旋转角度的训练样本输出的相关峰值波动性较大,不便于后续探测和处理等问题,对常规综合鉴别函数到编码匹配滤波器的编码转化过程进行分析,找到导致相关峰值波动的原因,提出改进方法,即在计算综合鉴别函数的线性组合系数时将编码运算也考虑进去,并根据滤波器对各训练样本相关峰值的倒数来确定线性组合系数。计算机仿真结果表明:改进后的方法降低了复合滤波器对不同旋转角度样本输出相关峰值的波动性,提高了相关峰自动判别的准确性。  相似文献   
962.
Surface measurement using active vision and light scattering   总被引:3,自引:0,他引:3  
This paper reviews the recent progress in surface measurement methods using active vision and light-scattering techniques. The active vision methods with different structured light patterns and the corresponding techniques are summarized. The surface roughness and defects inspection with light-scattering are discussed. After the review, an integrative method to measure surface waviness and form, roughness is proposed.  相似文献   
963.
本文提出一种光闸条纹的轮廓推算法,同日本人提出的方法相比,此法简单而且概念明确。文中采用两种方法来验证推算法的正确性,即将常用的计算法计算的及实测的轮廓数值和推算的轮廓数进行比较,结果颇为满意。  相似文献   
964.
A digital speckle pattern interferometer with optical fibres is proposed for composite materials diagnostics in an operative environment. Detection of a variety of flaws, such as disbonds, delaminations and cracks in aircraft components, is reported. Additional fringes are introduced for linearizing the fringe pattern and obtaining quantitative deformation measurements by Fourier transform analysis.  相似文献   
965.
Light amplification was successfully demonstrated in an all-organic light transducer based on hybridization of an organic electroluminescent diode and a perylene pigment film as an electron photoinjecting electrode. Amplification gain of photon conversion from red to red light reached 25 with the assistance of effective electron photoinjection due to large photocurrent multiplication in a perylene film. Optical switching behavior caused by feedback of output-light to the photoconductive layer was observed.  相似文献   
966.
基于Log-Polar变换的星图识别方法   总被引:1,自引:0,他引:1  
魏新国  张广军  江洁 《光学技术》2006,32(5):678-681
基于Log-Polar变换提取特征模式,并将特征模式进行字符串编码,在KMP算法的基础上给出一种适合于星图识别的字符串匹配算法用以实现观测星和导航星的匹配识别。与栅格算法在相同实验条件下的比较表明:该方法对星点位置噪声和星等噪声具有更强的抗干扰能力,且具有更小的存储容量,但其识别速度还有待于进一步提高。  相似文献   
967.
We report here a novel in-situ synthetic method for the preparation of poly (o-methoxyaniline) and palladium nanoparticle composite material. Ortho-Methoxyaniline and palladium acetate were used as the precursors; during the reaction o-methoxyaniline was oxidized and forms poly (o-methoxyaniline) and palladium acetate is reduced forming palladium nanoparticles. IR and Raman spectra provide information on the structure of the polymer. The TEM and SEM analysis are used to determine the size of the nanoparticles and the morphology of the polymer respectively.  相似文献   
968.
The solid-state NMR experiment PISEMA, is a technique for determining structures of proteins, especially membrane proteins, from oriented samples. One method for determining the structure is to find orientations of local molecular frames (peptide planes) with respect to the unit magnetic field direction, B0. This is done using equations that compute the coordinates of this vector in the frames. This requires an analysis of the PISEMA function and its degeneracies. As a measure of the sensitivity of peptide plane orientations to the data, we use these equations to derive a formula for the intensity function in the powder pattern. With this function and other measures, we investigate the effect of small changes in peptide plane orientations depending on the location of the resonances in the powder pattern spectrum. This gives us an indication of the change in lineshape due to mosaic spread and a way to interpret these in terms of an orientational error bar.  相似文献   
969.
提出了一种用于高功率微波武器的等离子体通道天线(PCA),计算了该天线的辐射方向图。推导出了一般性天线的辐射方向函数;建立了PCA的近似电磁模型;给出了圆坐标系下PCA和周围空气中的电磁场,利用边界条件得出了PCA的色散方程,求出PCA的表面波波矢。重点讨论了PCA的辐射场随等离子体密度、天线长度、半径的变化,证实了PCA方向图的可控性。  相似文献   
970.
Processing methods used in photonics and nanotechnology have many limitations hindering the ability to realize devices and restricting the actual number of applications. An ideal processing method should require low-cost equipment, be able to produce very fine details, and be scalable to process large area specimens in an acceptable amount of time. Proximity field nanopatterning (PnP) is a lithography method possessing these features. By using interference patterns produced by a two-dimensional phase mask, the technique is able to generate a submicron detailed exposure on a millimeter-size slab of light sensitive photopolymer, which is then developed like a photographic plate to reveal three-dimensional interference patterns from the phase mask. While it is possible to use computer aided simulations to obtain the interference patterns produced by a mask with a certain pattern, the inverse problem of producing a mask for a desired interference pattern cannot be solved in the same way due to the intricacies of light interactions involved in producing the final interference pattern. An alternative method is to iteratively optimize the phase mask so that the interference patterns obtained converge to the desired pattern. The method is elaborated in this article.  相似文献   
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