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61.
62.
The minimal quantization structure is employed to investigate the quantum version of the Stackelberg duopoly with continuous distributed asymmetric information, i.e a continuous distribution while the second mover has the first mover has incomplete information that obeys complete information. It is found that the effects of the positive quantum entanglement on the outcomes exhibit many interesting features due to the information asymmetry. Moreover, although the first-mover advantage is counteracted by the information asymmetry, the positive quantum entanglement still enhances the first-mover advantage and improves the first-mover tolerance of the information asymmetry beyond the classical limit. 相似文献
63.
64.
用数码相机实现未琅禾费衍射测量细丝直径 总被引:4,自引:1,他引:4
介绍利用激光获得丝夫琅禾费衍射图样,并采用数码相机实现计算机辅助非接触自动测量细丝直径的方法,以及将其用于设计性实验的尝试。 相似文献
65.
Sihua Xiang Author Vitae Sihai Chen Author Vitae Xin Wu Xiawei Zheng 《Optics & Laser Technology》2010,42(1):42-46
In the field of lidar system design, there is a need for laser scanners that offer fast linear scanning, are small size and have small a rotational inertia moment. Currently, laser scanners do not meet the above needs. A new laser scanner based on two amplified piezoelectric actuators is designed in this paper. The laser scanner has small size, high mechanical resonance frequencies and a small rotational inertia moment. The size of the mirror is 20 mm×15 mm. To achieve fast linear scanning performance, an open-loop controller is designed to compensate the hysteresis behavior and to restrain oscillations that are caused by the mechanical resonances of the scanner's mechanical structure. By comparing measured scanning waveforms, nonlinearities and scan line images between the uncontrolled and controlled scanner, it was found that the scanning linearity of linear scanning was improved The open-loop controlled laser scanner realizes linear scanning at 250 Hz with optical scan angle of ±12 mrad. 相似文献
66.
In recent years, spatial self-phase modulation (SSPM) with two-dimensional (2D) materials has attracted the attention of many researchers as an emerging and ubiquitous nonlinear optical effect. In this review, the state of the art of 2D material-based SSPM is summarized. SSPM measures or tunes the nonlinearity of 2D materials, and it is also an effective approach to study the band structure of 2D materials. Several modified forms of SSPM, such as high-order, white-light-excited, vector field excited, and optically nonlinearly enhanced SSPM are also presented. Subsequently, the physical origin of the SSPM formation mechanism is compared and analyzed. Furthermore, the applications of SSPM with 2D materials, including passive photonic devices, generation of Bessel beams, and identifying the mode of the orbital angular momentum, are listed. Finally, several urgent problems of the SSPM with 2D materials, potential applications, and prospects for future development are presented. 相似文献
67.
The ferroelectric polarization of triangular-lattice antiferromagnets induced by helical spin-spiral order is not explained by any existing model of magnetic-order-driven ferroelectricity. We resolve this problem by developing a general theory for the ferroelectric polarization induced by spin-spiral order and then by evaluating the coefficients needed to specify the general theory on the basis of density functional calculations. Our theory correctly describes the ferroelectricity of triangular-lattice antiferromagnets driven by helical spin-spiral order and incorporates known models of magnetic-order-driven ferroelectricity as special cases. 相似文献
68.
The mechanical properties of monolithic metallic glasses depend on the structures at atomic or subnanometer scales, while a clear correlation between mechanical behavior and structures has not been well established in such amorphous materials. In this work, we find a clear correlation of (27)Al NMR isotropic shifts with a microalloying induced ductile-to-brittle transition at ambient temperature in bulk metallic glasses, which indicates that the (27)Al NMR isotropic shift can be regarded as a structural signature to characterize plasticity for this metallic glass system. The study provides a compelling approach for investigating and understanding the mechanical properties of metallic glasses from the point of view of electronic structure. 相似文献
69.
ZHAO Chuan SUN Sheng-Sen LI Cheng ZHANG Xiao-Jie HE Kang-Lin AN Qi CHEN Hong-Fang DAI Hong-Liang FENG Chang-Qing HENG Yue-Kun HUANG Ya-Qi HUANG Yan-Ping GUO Jian-Hua LI Wei-Dong LI Xiu-Rong LIU Fang LIU Huai-Min LIU Shu-Bin LIU Shu-Dong LIU Yong MA Xiang MAO Ze-Pu SHAO Ming SUN Yong-Jie SUN Zhi-Jia WU Jin-Jie YANG Gui-An ZHAO Lei ZHU Xing-Wang ZUO Jia-Xu 《中国物理C(英文版)》2011,35(1):72-78
The time calibration for end cap TOF system of BESⅢ is studied in this paper.It has achieved about 110 ps time resolution for muons in dimu events.The pulse height correction using electronic scan curve and the predicted time calculated using Kalman filter method are introduced.This paper also describes the study of using electrons and muous as calibration samples. 相似文献
70.
We have developed a rigorous model for analyzing excess conduction loss in normal metals surface by using the spatial dispersion theory. We have used the model to account excess conduction loss and dissect the discrepancies between excess conduction loss measurements and classical theoretical predictions in normal metals surface below terahertz frequencies. Our analysis shows that the conductivity is not only frequency but also wave vector dependent. We demonstrate good quantitative agreement with the published experimental data for the room temperature excess conduction loss of normal metals surface below terahertz frequencies. 相似文献