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基于小波分析的条纹图滤波方法 总被引:2,自引:0,他引:2
本文提出了一种新颖的干涉条纹图非线性滤波方法,可以选择性地在频域图像的不同区域选用不同的滤波方式,在滤掉图像中大部分散斑噪声的同时,能够减少信息的损失,使图像的内部边界仍然保持清晰。文中首先简介了正交小波变换的原理,然后介绍了去除散斑噪声的具体算法,最后给出了计算机模拟去噪声的结果 相似文献
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建立了具有粗糙核的Hardy—Littlewood极大算子高阶交换子及其相应的分数次极大算子高阶交换子在齐次Morrey-Herz空间上的中心BMO估计,并由此得到了由一类次线性算子所生成的高阶交换子在齐次Morrey—Herz空间上的相应结果. 相似文献
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Three-dimensional (3D) simulations and theoretical analyses on super-short pulse generated using free- electron lasers (FELs) at perfect synchronism are carried out with the help of our 3D OSIFEL code. The evolution of longitudinal pulse width in the Japan Atomic Energy Research Institute (JAERI) experiment is simulated. The results show that the optical pulse is compressed on successive passes due to the slippage between the optical and electron beams, and an ultra-short 221-fs optical pulse is finally obtained, which agrees with the experiment. Furthermore, to shorten wavelength such as soft ultraviolet (SUV) spectrum range, an ultra-short pulse generated at perfect synchronism is analyzed and studied. Finally, the relationship between the optical pulse length compressed and the peak electron beam current is calculated. It shows that the higher the electron beam current, the shorter the output FEL width length, due to the higher gain. 相似文献
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The current and the voltage of an X-pinch were measured. The inductance of the X-pinch was assumed to be a constant and estimated by the calculation of the magnetic field based on the well-known Biot-Savart's Law. The voltage of the inductance was calculated with L · di/dt and subtracted from the measured voltage of the X-pinch. Then, the resistance of the X-pinch was determined and the following results were obtained. At the start of the current flow the resistance of the exploding wires is several tens of Ohms, one order of magnitude, higher than the metallic resistance of the wires at room temperature, and then it falls quickly to about 1 , which reflects the physical processes occurring in the electrically exploding wires, i.e., a current transition from the highly resistive wire core to the highly conductive plasma. It was shown that the inductive contribution to the voltage of the X-pinch is less than the resistive contribution. For the wires we used, the wires' material and diameter have no strong influence on the resistance of the X-pinch, which may be explained by the fact that the current flows through the plasma rather than through the metallic wire itself. As a result, the current is almost equally divided between two parallel X-pinches even though the diameter and material of the wires used for these two X-pinches are significantly different. 相似文献
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合成了一种新的带有光交联基团的电光聚合物,其高分子基体是双酚A环氧树脂,二阶非线性生色团对硝基苯胺和光交联基团肉桂酰氯都键接在高分子链上.将聚合物溶解后旋涂成膜,对薄膜进行电晕极化.极化的后阶段用紫外光照射,使聚合物体系交联成网络结构,形成生色团取向长时间稳定的聚合物电光薄膜.用这种聚合物电光薄膜构成外部电光调制系统,测量了共面波导上的电信号. 相似文献
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运用Simufact有限元软件建立了三辊斜轧两道次成形多台阶涡轮轴的仿真模型, 通过数值模拟分析了涡轮轴成形情况, 探究了减径量对轧制过程中轧制力、等效应力-应变以及外圆度误差的影响规律. 结果表明: 随减径量的增大, 轧件第1道次和第2道次的径向载荷、等效应力、等效应变和外圆度误差均呈增大趋势. 综合比较3种方案下的轧件成形情况, 方案2为最佳的道次减径量分配方案, 即第1道次减径6mm, 第2道次各台阶减径量分别为2、9和14mm. 相似文献