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101.
针对现有成像系统因数据冗余而无法兼顾大视场、高分辨、高效性的问题,结合人眼视网膜变分辨成像和并列式复眼成像原理,设计一种多分辨率成像的复合仿生成像系统.该成像系统按照球面和平面兼顾的曲面布局方式,利用11个相机镜头构建相机阵列,组成了四个等级分辨率的子眼拍摄模块.通过物距100 m的远景实验和物距10 m的近景实验发现,该系统在实现高分辨成像的同时,获得总视场达150.8°×37.8°.多分辨率成像实验结果表明,该系统获取的图像的分辨率从中心视场到边缘视场逐渐降低,并且相较于中心清晰全视场成像,四级分辨率成像的拼接图像数据量减少了17.2倍的数据冗余. 相似文献
102.
Propagation dynamics of the cosh-Airy vortex(CAiV) beams in a chiral medium is investigated analytically with Huygens–Fresnel diffraction integral formula. The results show that the CAiV beams are split into the left circularly polarized vortex(LCPV) beams and the right circularly polarized vortex(RCPV) beams with different propagation trajectories in the chiral medium. We mainly investigate the effect of the cosh parameter on the propagation process of the CAiV beams.The propagation characteristics, including intensity distribution, propagation trajectory, peak intensity, main lobe's intensity, Poynting vector, and angular momentum are discussed in detail. We find that the cosh parameter affects the intensity distribution of the CAiV beams but not its propagation trajectory. As the cosh parameter increases, the distribution areas of the LCPV and RCPV beams become wider, and the side lobe's intensity and peak intensity become larger. Besides, the main lobe's intensity of the LCPV and RCPV beams increase with the increase of the cosh parameter at a farther propagation distance, which is confirmed by the variation trend of the Poynting vector. It is significant that we can vary the cosh parameter to control the intensity distribution, main lobe's intensity, and peak intensity of the CAiV beams without changing the propagation trajectory. Our results may provide some support for applications of the CAiV beams in optical micromanipulation. 相似文献
103.
The ability to control the flow of quantum information is deterministically useful for scaling up quantum computation. In this paper, we demonstrate a controllable quantum switchboard which directs the teleportation protocol to one of two targets, fully dependent on the sender’s choice. Importantly, the quantum switchboard also acts as a optimal quantum cloning machine, which allows the receivers to recover the unknown quantum state with a maximal fidelity of . This protects the system from the complete loss of quantum information in the event that the teleportation protocol fails. We also provide an experimentally feasible physical implementation of the proposal using a coupled-cavity array. The proposed switchboard can be utilized for the efficient routing of quantum information in a large quantum network. 相似文献
104.
针对RC梁开裂荷载计算方法尚未统一的现状,首先,结合18根RC梁试验数据对比了已有的6种RC梁开裂弯矩计算公式,发现开裂弯矩理论计算值与试验值的偏差大小和混凝土强度有关;然后,通过提出塑性变形发展程度系数k,推导新的RC梁开裂弯矩计算公式,并进一步基于k值和塑性影响系数计算值γk进行改进;最后,选取12根RC试验梁验证改进公式的准确性,证明改进公式的计算值与试验值吻合更好且偏于安全。 相似文献
105.
将凝胶渗透色谱(GPC)中的示差与紫外检测器联用,测定了无规共聚丁苯橡胶和SBS三元嵌段共聚物中各级分的组成变化.实验方法选择中对比了两种浓度参数的确定方法,发现通过改变注射量来实现浓度变化的方法优于使用系列浓度样品的方法.分别测定标准样品在紫外和示差检测器上信号产生的时间间隔可以确定两个检测器上信号的时间差.根据紫外-示差检测器联用可以看到SBR无规共聚物和三嵌段SBS共聚物样品中每一个级分中随着相对分子质量的变化,苯乙烯含量的变化. 相似文献
106.
107.
Dynamics of refractory atom reactions have been studied with a crossed beam apparatus combining two pulsed, supersonic molecular beam sources, a pulsed UV laser for creating the refractory atoms in the gas phase by laser ablation, and a pulsed dye laser to probe the reaction products by laser-induced fluorescence. Examples of the A1(2Pj) + O2(X3∑g)→ A10(X2∑+) + O(3Pj), Mg(1So) + N2O(X1∑+) → MgO(X1∑+,a3Π) + N2(X1∑g+) andC(3Pj) + NO(X2Πr) → CN(X2∑+) + 0(3Pj) systems are given. Comparisons with the studies performed using the conventional steady-state beam approach are made. 相似文献
108.
109.
We quantitatively modeled the volume phase transition of a hydrogel containing a crystalline colloidal array with a crown
ether ligand which binds Pb2+. The hydrogel volume response and the wavelength diffracted depend on the Pb2+ concentration and on both the ionic strength and the valence of the nonbinding ionic species. We successfully modeled the
response of this hydrogel Pb2+ sensor to ionic strength and the cation valence of the added salts.
Figure Cation identity dependence of crown ether photonic crystal Pb+ sensing 相似文献
110.
High-performance liquid chromatography (HPLC) fingerprint has been commonly used in the quality control and assessment of herbal medicines, and two-dimensional (2D) fingerprint obtained by means of HPLC-diode array detector (HPLC/DAD) can provide higher reliability. In this paper, an approach to the analysis of the 2D HPLC/DAD fingerprints, which was based on digital image recognition techniques, was developed for the first time. First, wavelet transform was employed to eliminate noise signal in the 2D fingerprint, and then the 2D fingerprint was converted into grayscale image. Second, several features of the image were calculated, and hierarchical clustering. This approach was applied to the qualitative analysis of the different samples of coptis chinensis, and the clustering result of samples was all highly consistent with the real situation. Based on the densities in grayscale image, three components in standard samples were quantitative analyzed, and the obtained correlation coefficients between concentration and grayscale density were more than 0.999. Our study indicated that the analysis of the 2D HPLC/DAD fingerprint was successful based on the idea and techniques of digital image recognition techniques, and this proposed approach provided a new pathway for the analysis of two-dimensional spectrums. 相似文献