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61.
柔性低温多晶硅薄膜晶体管的弯曲稳定性   总被引:1,自引:0,他引:1  
研究了以聚酰亚胺为基板的p型低温多晶硅薄膜晶体管在不同弯曲半径下的偏压稳定性。当曲率半径从15 mm变到3 mm时,在拉伸弯曲状态下,阈值电压和平坦时保持一致(Vth=-1.34 V),迁移率μsat从45.65 cm~2/(V·s)降到45.17 cm~2/(V·s),开关比增大;在压缩弯曲状态下,转移特性曲线和平坦状态保持了非常好的一致性。在最小弯曲半径为3 mm时,进行了正负偏压稳定性测试,结果表明,器件依然具有很好的稳定性。  相似文献   
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.
岳鹏  文爱军  易湘  毋丹芳 《光子学报》2008,37(2):279-282
提出了一种改进型光可分突发交换性能分析模型(Modified Optical Composite Burst Switching,MOCBS).该模型考虑了截断剩余造成的影响,通过分析截断概率、平均截断剩余长度,得到截断剩余造成的分组丢弃概率,从而更准确地估计分组丢失率.在此基础上,推导出支持区分服务的POCBS(Prioritized OCBS)性能分析公式.仿真验证了MOCBS的准确性以及POCBS分析公式的有效性.  相似文献   
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.
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.
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.
就"教育部高等学校光电信息科学与工程专业教学指导分委员会及协作委员会2007年全体会议"内容,阐明了学科交叉对该学科教学模式和课程设置提出的诉求。从培养方案的知识体系结构入手,分析了现有教学模式存在缺乏纵向衔接和横向贯通的问题,并通过设置"交叉课程",成立关联课程"学科组"、开设"系统设计"课程和加强创新性实验四个方面入手,提出了改善培养模式,提高教学质量的建议。  相似文献   
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