排序方式: 共有57条查询结果,搜索用时 15 毫秒
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把模糊集理论中的模糊关系应用于对色彩相似性的判断,并在彩色图像的检索中进行了应用.其中仅使用了一种基于色彩空间的矢量表达的隶属函数即可分别计算出待检索图像与库图像对应特征色之间的相似性程度,并用α级关系来抽取其中的一些彩色图像,给出检索结果.在进行色彩相似性的计算中还采用了逐级筛选法及色彩矢量分区比较法,从而避免了大量涉及无关的色彩矢量的计算,有效地降低了红绿蓝(RGB)空间的色彩相关性,提高了检索准确性及检索速度
关键词:
模糊关系
色彩相似性
彩色图像检索
色彩矢量分区比较法 相似文献
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采用单管静电纺丝的方法成功制备了纯的与Yb掺杂的In_2O_3纳米管(Yb-In_2O_3).利用扫描电子显微镜和X射线衍射对样品的结构和形貌进行了表征,制作了基于纯In_2O_3和Yb-In_2O_3纳米管的气敏元件.研究表明,Yb-In_2O_3纳米管气敏元件在230℃下对100 ppm甲醛的灵敏度为69.8,是纯In_2O_3纳米管气敏元件对同浓度甲醛灵敏度(18.4)的3.8倍,其对100 ppm甲醛的响应恢复时间分别为4 s和84 s.并且,基于Yb-In_2O_3纳米管的气敏元件对100 ppb甲醛的灵敏度达到2.5.此外,该气敏元件还具有出色的选择性及稳定性,具备良好的实际应用前景. 相似文献
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The paper describes a novel method for copper preconcentration using microcrystalline triphenylmethane loaded with malachite green prior to the determination by the flame atomic absorption spectrometry (FAAS). Under the optimum conditions, Cu(Ⅱ) can be totally adsorbed on the surface of microcrystalline triphenylmethane, and completely separated from Pb(Ⅱ), Cd(Ⅱ), Co(Ⅱ), Cr(Ⅲ), Ni(Ⅱ), Mn(Ⅱ), Fe(Ⅲ) and Al(Ⅲ) by controlling acidity. The preconcentration factor of this proposed method is 200. The recovery is in a range of 97.5%-105%. The relative standard deviation (RSD) is not beyond 3.0%. The proposed method has been successfully applied to the determination of trace copper in various water samples with satisfactory results. 相似文献
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根据谐衍射元件的特殊色散原理及红外波段的窗口特性,将谐衍射透镜应用于红外超光谱探测器中.阐述了利用衍射光学元件色散特性的新型红外双波段超光谱探测成像的基本原理,给出了具体的系统设计实例.设计结果表明,此系统提高了图像的分辨率,增大了接收光能量的能力.在两个波段内同时较好地完成了系统的像差校正,波前差都小于1/4波长.在20线对/mm时, 光学传递函数在这两个波段内的各个变焦位置均达到衍射极限.
关键词:
谐衍射元件
超光谱探测
光学设计 相似文献
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ZHANG Jian-Fu RUAN Xi-Chao HOU Long LI Xia BAO Jie ZHANG Guo-Guang HUANG Han-Xiong SONG Chao-Hong 《中国物理C(英文版)》2010,34(7)
The light output functions for protons of ST-401 and BC-408 plastic scintillators were measured using white neutron source produced by the 9Be(d,n)10B reaction at the HI-13 Tandem Accelerator at China Institute of Atomic Energy(CIAE).The LOFs of plastic scintillators for protons in the energy range of 0.516.5 MeV were obtained by the time-of-flight(TOF)technique and an iterative procedure.Two parameters(kB and C)were deduced by fitting the experimental data. 相似文献
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Xiu-Lao Tian Xiao-Qiang Xi Guo-Fang Shi Ming-Liang Hu Guo-Guang Yao 《Optics Communications》2009,282(24):4815-4818
We propose the tensor representation of teleportation and controlled teleportation. By using this representation, it is easy to describe the process of teleporting an unknown N-qubit state via a genuine 2N-qubit channel, and to find the necessary and sufficient condition of realizing a successful teleportation (which is determined by the measurement matrix Tα and the quantum channel parameter matrix X). For controlled teleportation, if composing tensor representation with graph, one can easily design any kind of controlled teleportation. As examples, we give a scheme of symmetrically controlled teleportation of two-qubit states and a scheme of representative network controlled of three-qubit states. This method can also be generalized to the controlled teleportation of N-qubit states. 相似文献