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21.
Mao Guangjun Li Zhuxia Zhuo Yizhong Han Yinlu Yu Ziqiang M. Sano 《Zeitschrift für Physik A Hadrons and Nuclei》1994,347(3):173-179
The collision term has been deduced based on the effective Lagrangian in addition to the mean-field. We propose the momentum- and density-dependent coupling strengths for scalar and vector fields. The saturation properties of nuclear matter, the experimental data of the energy-dependent optical potential and the mean free path in the nuclei can be reproduced simultaneously. The in-mediumn–n cross section has also been calculated for different densities and energies, our results are consistent with Dirac-Brueckner-Hartree-Fock calculations.Supported by National Natural Science Foundation of China 相似文献
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摘要本文利用基样条插值方法,给出非等距I型三次样条插值误差的余项渐近展开式,推广了文献[1]中的结果。 相似文献
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摘要本文用Feynmann路径积分方法,研究了一种U(1)规范场理论中的Casimir效应。在一圈图近似下,计算了带电标量场在两个平行的理想金属板之间的Casimir能,并对低维情况进行了讨论。 相似文献
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In this paper, the so-called local likelihood method is suggested for solving the change point problems when the data are distributed as multivariate normal. The detection procedures proposed not only provide strongly consistent estimates for the number and locations of the change points, but also simplify significantly the computation. 相似文献
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This study investigates the robust output tracking problem for a class of uncertain linear systems. The uncertainties are assumed to be time invariant and to satisfy the matching conditions. According to the selected nominal parameters, an optimal solution with a prescribed degree of stability is determined. Then, an auxiliary input via the use of an adapting factor, connected to the nominal optimal control, is introduced to guarantee the robustness and prescribed degree of stability for the output tracking control of the uncertain linear systems. This method is very simple and effective and can reject bounded uncertainties imposed on the states. A maglev vehicle model example is given to show its effectiveness. 相似文献
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Affective property of image and fractal dimension 总被引:3,自引:0,他引:3
Affective information processing is an advanced research direction in the AI world. Affective Information of image was taken as the objective of research in this paper. The influence of color vision properties’ histograms of image on human emotions was analyzed. Then based on fractal theory, the fractal aspect of different kinds of images was analyzed in keeping with the space domain. After that, psychological testing method of semantic difference was applied to verify the uniformity of the objective and subjective evaluations. At last, a conclusion was drawn that image having different affective properties could be classified by their fractal dimensions. 相似文献
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A two-dimensional (2D) subwavelength nanostructure for antireflection coating is fabricated upon a transparent substrate. Self-assembled 2D colloidal crystals are used as a nanoscale composite material with controlled thickness and low refractive index. The feature size of the structure is approximately 105 nm. The structure is used for antireflection coating, and the measured reflectivity of a glass substrate is reduced to 0.3%. Enhanced transmission through the substrate is also observed. 相似文献
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Positron-lifetime experiments have been carried out on two undoped n-type liquid encapsulated Czochralski (LEC)-grown InP samples with different stoichiometric compositions in the temperature range 10-300 K. For temperatures below 120 K for P-rich InP and 100 K for In-rich InP, the positron average lifetime began to increase rapidly and then leveled off, which was associated with the charge state change of hydrogen indium vacancy complexes from (VInH4)+ to (VInH4)0. This phenomenon was more obvious in P-rich samples that have a higher concentration of VInH4. The transformation temperature of approximately 120 K suggests that the complex VInH4 is a donor defect and that the ionization energy is about 0.01 eV. The ionization of neutral VInH4 accounted for the decrease of the positron average lifetime when the sample was illuminated with a photon energy of 1.32 eV at 70 K. These results provide evidence for hydrogen complex defects in undoped LEC InP. 相似文献