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基于视觉的图像处理技术逐渐成熟,将图像处理应用在工件检测中也被广泛认同;利用图像检测螺纹的技术和装置也不断被改进和完善。针对螺纹图像检测中连续性较低、精度不高的问题,设计了一种连续自动螺纹检测系统。在圆盘上均匀分配四个工位,由电机和分割器带动,实现螺纹检测过程的放置提取、工件判断、表面除杂以及图像采集四个过程;高精度工业相机获取的螺纹图像,应用Labview中Vision assistant模块,实现图像的几何畸变矫正、边缘检测、目标分割、图像标定、参数计算和检测。经过实验证明,该系统实现了螺纹检测的自动化,并且提高了螺纹检测的精度。 相似文献
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斯特林制冷机回热器采用间隙密封,可以在完成密封作用的同时消除接触磨损和因此而产生的污染。但由于间隙内气体的泄漏,引起了冷量损失,使制冷量减少。文中建立了间隙密封式斯特林制冷机间隙泄漏率的数学物理模型,并获得了密封间隙的泄漏率的表达式。 相似文献
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Applying invariant eigen-operator method to deriving normal coordinates of general classical Hamiltonian 下载免费PDF全文
For classical Hamiltonian with general form H = 1/2 ∑ ij Mijpipj + 1/2 ∑ ij Lijqiqj we find a new convenient way to obtain its normal coordinates, namely, let H be quantised and then employ the invariant eigen-operator (IEO) method (Fan et al. 2004 Phys. Lett. A 321 75) to derive them. The general matrix equation, which relies on M and L, for obtaining the normal coordinates of H is derived. 相似文献
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船型网箱是一种新型抗风浪深水网箱, 其采用船形结构以及单点系泊方式, 合理的锚泊系统设计是保证船型网箱安全可靠的关键. 依据Stokes二阶波浪理论和Morison方法, 采用数值方法分析了锚泊系统串联浮筒对船型网箱水动力特性的影响以及不同波况作用下浮筒位置、大小对锚绳力的影响, 并进行了物理模型实验验证. 结果表明, 船型网箱最大锚绳力随着波高的增大而增大, 随周期变化不明显; 串联浮筒增加了浮架纵向位移, 使得浮架相对水质点速度减小, 从而减小了浮架所受最大波流力以及锚绳力; 最大锚绳力随着浮筒直径增加先减小后增大, 随着浮筒位置远离浮架连接点而减小. 相似文献
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We study the long-time limit behavior of the solution to an atom's master equation. For the first time we derive that the probability of the atom being in the α-th (α = j + 1 -jz, j is the angular momentum quantum number, jz is the z-component of angular momentum) state is {(1 - K/G)/[1 - (K/G)2j+1]}(K/G)^α-1 as t → +∞, which coincides with the fact that when K/G 〉 1, the larger the a is, the larger the probability of the atom being in the α-th state (the lower excited state) is. We also consider the case for some possible generaizations of the atomic master equation. 相似文献
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In this paper, we propose the so-called continuous Fresnel-wavelet combinatorial transform which means that the mother wavelet undergoes the Fresnel transformation. This motivation can let the mother-wavelet-state itself vary from |ψ> to Fr,s+ |ψ> , except for variation within the family of dilations and translations. The Parseval's equality, admissibility condition and inverse transform of this continuous Fresnel-wavelet combinatorial transform are analysed. By taking certain parameters and using the admissibility condition of this continuous Fresnel-wavelet combinatorial transform, we obtain some mother wavelets. A comparison between the newly found mother wavelets is presented. 相似文献
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