查询词典 aperture

Measures such as area ratio (the area under the aperture opening divided by the surface area of the aperture wall) and aspect ratio (aperture width divided by stencil thickness) can be used to determine appropriate aperture sizes.

因此，严格控制孔的质量是钢网成功设计的关键。特别是小量沉积材料要求精度高时的高精度要求。

It was illuminated that the width of the centre bright fringe decreased along with the increasing width of the rectangular aperture when the effect of the aperture on the beam couldn't be ignored,however,the width of centre bright fringe step changed with increase of the size of the aperture when the effect could be ignorable,the width of the half maximum intensity of the centre bright fringe decreased along with the accretion of the width of the aperture and then it tends to a constant.

结果表明，当光阑对光束的衍射影响明显时，光束衍射场的中央亮条纹的宽度随着光阑边长的增大而减小；当光阑对光束的衍射影响极小时，中央亮条纹的宽度随着光阑边长的增加而阶跃变化，中央亮条纹强度的半最大值宽度随着光阑边长的增大而减小；当光阑对光束衍射影响极小时，中央亮条纹半最大值宽度趋近于一定值。

The invention provides an insulation pad which is provided with high strength and high friction between a rail cap and a clamp, wherein the pad uses stainless steel as base, two faces of the pad are baked with enamel which is sanded and roughens the surface to brush a layer of silicon rubber, the outline is the same as the inside surface of the rail joint, the aperture on the pad and aperture distance are the same as the aperture and aperture distance of the clamp.

本发明就是制造一个钢轨端头与夹板间的高强度、高摩擦力的绝缘垫板，该垫板的由不锈钢板为基底，双面烤上搪瓷，搪瓷面先经喷砂处理，使其表面粗糙后，刷上一层的硅橡胶，轮廓与钢轨接头内侧表面相同，该垫板上的孔径与孔距与钢轨与夹板的孔径与孔距相同。

The position and size of the monochromator, focusing curvature radii and tilting angles of the germanium focusing monochromator under different different take-off angle, size and divergency of the second collimator and intensity loss due to the use of it were determined. The neutron flux at different wavelength, under different reflection and take-off angle of the monochromator and divergency of the first collimator, were given. The simulation on the aperture used for limiting beam size in front of the sample showed that, smaller the size of the aperture and further the distance from the aperture to the sample, greater the loss of the intensity and more serious the spread of the beam along vertical direction at the sample position which makes the practical sampling volume greater than expected.

用蒙特卡罗模拟方法对中子应力衍射谱仪的设计方案进行了优化研究，提出了一系列可供参考的数据：确定了单色器的位置、尺寸、垂直聚焦单色器在不同起飞角下的聚焦曲率半径和倾角；讨论了第二准直器的尺寸和发散，以及使用第二准直器造成的强度损失；给出了在不同单色器反射面、起飞角、中子波长和第一准直器发散度的情况下样品处的中子注量率，以及多种组合情况下谱仪的分辨率曲线；对限束方孔的尺寸、距离样品远近对强度损失和测量中的影响做了深入研究。

The hard-edge aperture is "moved out" in an complicated optical system, which means to transfer the system with such hard-edge aperture into an optical system with entrance and exit pupils, and the hardedge aperture is taken as an exit pupil so as to find the analytical solution of a light beam.

把硬边光阑从复杂光学系统中"移"出来，即把任意一个含有硬边光阑的复杂光学系统体现到含有入射光瞳和出射光瞳的光学系统中，使硬边光阑的作用转化为出射光瞳的作用，以便求出观察面上的解析解。

This utility model disclosed a dust removal equipment, environmental protection, their characteristics is that, including filters, dust collection equipment and negative pressure ventilation machines, referred to the vertical filter settings are arranged in descending sequence multi-aperture filter, its Set large aperture filters connected at one end of inlet pipe, set a small aperture at one end of filters connected through the vacuum exhaust fan out of the wind pipe, dust collection equipment installed in the bottom of each layer filters.

本实用新型公开了一种环保除尘设备，其特征在于，包括过滤器、集尘装置和负压抽风机，所述过滤器内垂直设置有多层孔径依次从大到小排列的过滤网，其设置有大孔径过滤网的一端连接进风管，设置有小孔径过滤网的一端通过负压抽风机连接出风管，集尘装置设置在每层过滤网的下端。

Based on the expression of diffractive field distribution of the Gaussian beams restricted by a rectangular aperture and focalized by a lens,the relationship between the width of the rectangular aperture and the spot size of the restricted beam,as well as the relationship between the aperture width and the power in the bucket,was numerically calculated with MATLAB.

为了研究矩形光阑边长与透镜像方焦面处光束光斑尺寸以及光斑内所包含功率的关系，根据高斯光束经矩形光阑和透镜变换后在透镜像方焦面的衍射场分布表达式，采用MATLAB进行数值计算的方法，进行了理论分析。

The first is termed aero-optic and involved optical transmission through aberrating fluid layer whose thickness, L, is smaller than or comparable with the viewing aperture dimension, A, and the turbulence scales, A , are smaller than or the order as the layers thickness:The second category, atmospheric propagation, involved optical transmission through the aberrating medium over very long propagation distance compare with the viewing aperture size, and the turbulent scales of note are generally less than or the same order as the propagation distance:Depending on the atmospheric conditions, for ground-based observatories, wave-front sensor operating at 300HZ can adequately resolved both the important spatial scales and the temporal evolution of the atmospheric-turbulence-induced aberrating wave front over viewing aperture associated with relatively large telescope.

第一类问题光学畸变发生在&近场&较短的光路上，即流层厚度L，光束直径A，以及湍流尺度Λ三者之间存在关系式：ΛA≤L≤A第二类大气传输问题光学畸变则发生在较长的一段光路上，L，A，以及Λ满足： A＜＜Λ≤L对于地基情况下的大气光学传输，300Hz的波前传感器就能实时地测得光波前畸变包括时间、空间频率的相关信息，为我们的自适应光学系统的设计、制造以及进行相关的自适应校正都有着相当重要的指导意义。

When the receiving aperture is much larger than the scattering disk scale, the aperture-smooth effect is remarkable and the derived variance approximates the result given by weak-fluctuation theory for any zenith; when the receiving aperture is much smaller than the scattering disk scale, the low-pass filter effect of the scattering disk scale is dominating and weak-fluctuation theory is valid only for small zeniths.

散射盘尺度和接收孔径对到达角起伏起平滑作用，当接收孔径远大于散射盘尺度时，由于孔径平滑作用，导出的表达式在任意天顶角都可以近似为弱起伏理论给出的结果；当接收孔径小于散射盘尺度时，散射盘尺度的平滑作用明显，接收孔径的平滑作用相对较小，传统的到达角起伏理论仅在小天顶角是适用的，在大天顶角必须用新导出的方差表达式。

ABSTRACT In this dissertation a number of theoretical and technical problems to be faced in applying synthetic aperture techniques to remote sensing of the earth are resolved, researching on synthetic aperture microwave radiometric imaging technology against the background of developing satellite microwave radiometric imaging system.

全文主要以星载微波辐射成像系统的研制为背景，对合成孔径微辐射成像技术进行了研究和探索，解决了将合成孔径技术移植到地球遥感领域存在的一些具。。。

Article 144 The Government of the Hong Kong Special Administrative Region shall maintain the policy previously practised in Hong Kong in respect of subventions for non-governmental organizations in fields such as education, medicine and health, culture, art, recreation, sports, social welfare and social

第一百四十四条香港特别行政区政府保持原在香港实行的对教育、医疗卫生、文化、艺术、康乐、体育、社会福利、社会工作等方面的民间团体机构的资助政策。原在香港各资助机构任职的人员均可根据原有制度继续受聘。

Small wonder, then, that the Chinese spend more in the shop than any other group of foreign visitors do .

这样的小惊喜，使中国顾客比任何国家的人消费得更多。