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1.
本文提出了一种图像调制原理,即用一族密条纹调制另一幅条纹图,使其适于光学处理,称为光载波,并介绍了它在条纹图倍增中的应用。这是一个对光测力学中各种干涉条纹都适用的普遍方法。  相似文献   

2.
该文用Fourier光学方法分析了分离一定距离的2个Ronchi光栅产生的Moire条纹。在第二块光栅后面直接观察,所得Moire条纹实质上为多光束干涉条纹。在第二块光栅后面加上滤波系统,适当滤波后,Moire条纹成为三光束干涉条纹或双光束干涉条纹。文中对滤波后的Moire条件进行了理论分析,给出了零号频谱滤波和Ⅰ号频谱滤频波下Moire条纹的方程和对比度,得到条纹的方程和对比度与两光栅间距的关系,并给出了与理论相一致的实验结果。  相似文献   

3.
大型锻件温度高,测量条件恶劣、误差较大,精确的尺寸测量可有效减少加工余量并提高材料的利用率.以高温锻件图像采集方法为基础,双目视觉结合结构光法可用于大型锻件尺寸在线测量.为消除干扰光线对在线测量锻件尺寸的影响,提出通过对单幅锻件结构光图像处理提取结构光条纹中心线的方法.该方法利用结构光条纹在截面上近似高斯分布的特点,首先根据设定阈值在行方向上搜索,并确定结构光条纹及干扰光线的起始位置;其后从起始位置开始沿光条纹在设定范围内搜索,并判断光条纹截面是否近似符合高斯分布以去除干扰光线;最后以结构光条纹起始位置为起点上下搜索,并计算结构光条纹的亚像素中心.实验结果表明:该方法具有计算简单、实现快速、稳定性好的特点,可用于大型锻件尺寸测量中结构光条纹中心线的提取.  相似文献   

4.
实验研究了非均匀管径放电管中直流辉光放电发光条纹的特性及条纹特性的影响因素,设计了一种阶梯状的放电管,并测试了条纹间距与管径、电流和气体气压等因素的关系. 结果表明,不同管径处的条纹间距明显不同,条纹间距与管径之间具有分数指数关系;气压升高使条纹间距几乎呈线性下降;放电电流密度增大使条纹间距略微增加.  相似文献   

5.
对影响迭加条纹黑白条纹比例关系的动片条纹、定片条纹等因素进行了深入探讨,并通过对实验数据的分析找出了影响迭加条纹黑白比例关系的因素及其规律性。  相似文献   

6.
干涉条纹提取是干涉条纹图象自动定量分析的基础.本文提出一种有效的干涉条纹提取算法.首先检测出条纹曲线点,然后对被检测出的条纹曲线点进行跟踪和断口连接.文中详细讨论了条纹曲线点检测原理、条纹曲线点跟踪及断口连接准则,并给出了令人满意的实验结果.  相似文献   

7.
在一定温度下的掺杂铜氧化合物高温超导体中,空穴间的强库仑关联作用和对关联的竞争使得在一定温度下条纹相与超导相共存。从一个二维格点模型出发,重点研究自旋调制对条纹相的影响,利用Fortran程序计算出不同的序参量下的条纹结果并用Matlab画出相应的图形,分析不同的序参量对条纹的影响,并试图探讨条纹相和超导相之间的微妙关系。  相似文献   

8.
为了实现虚拟光弹性力学实验,提出并采用了一种基于有限元计算和理论分析确定虚拟应力条纹图的反演方法,对巴西圆盘径向压缩实验的光弹性实验结果进行了模拟,并将反演获得的应力条纹图同真实实验获得的条纹图进行了对比分析。结果表明,反演获得的应力条纹图同实验结果一致,该方法实现了在虚拟光弹性力学实验中的定量分析。该方法对虚拟光弹性力学实验研究具有可参考价值。  相似文献   

9.
利用具有大剪切量的横向剪切干涉法获得了有限长的水平圆管在自然对流条件下的稳态以及降温过程的实时条纹,提取出条纹相位以及背景条纹相位并将两者求差得到相位差分布,给出了经过端部效应修正后的温度场分布.实验结果表明:利用具有大剪切量的横向剪切干涉法获得的实时干涉条纹类似于利用马赫-曾德干涉仪获得的简单条纹,可以简单而精确地提...  相似文献   

10.
研究形成凸条纹毛衫面料的各种编织方法并分析各种编织方法形成的凸条纹毛衫面料特点.通过对毛衫面料小样的分析,得出形成凸横条纹面料、凸竖条纹、凸波折条纹的编织方法及各种方法形成的面料特点,并且根据凸条纹面料的立体效果的强弱对各种编织方法进行排列.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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