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71.
甘师信  梁汉营 《数学杂志》1996,16(2):171-178
本文建立了B值鞅的极大函数f,平削函数fp^#,fp^#的凸Φ-不等式,反过来用这些不等式刻划了Banach空间的凸性和光滑性,同时给出了超自反空间以及与Hilbert空间同构的Banach空间的特征。本文的结论推广了一些熟知的重要结果。  相似文献   
72.
<正>To assist with the commissioning [1] of the Five-hundredmeter Aperture Spherical radio Telescope (FAST), we performed a pulsar search, with the primary goal of developing and testing the pulsar data acquisition and processing pipelines. We tested and used three pipelines, two (P1 and P2 hereafter) searched for the periodic signature of pulsars  相似文献   
73.
In the strange metal phase of the high-Tc cuprates, it is challenging to explain the linear temperature dependence of the in-plane resistivity and the quadratic temperature dependence of the inverse Hall angle. In this paper, we investigate the temperature dependence of the in-plane resistivity and inverse Hall angle in the nonlinear electrodynamics holographic model developed in our recent work. Maxwell electrodynamics and Born-Infeld electrodynamics are considered. Both cases support a wide spectrum of temperature scalings in parameter space. For Maxwell electrodynamics, the T-linear in-plane resistivity generally dominates at low temperatures and survives into higher temperatures in a narrow strip-like manner. Meanwhile, the T-quadratic inverse Hall angle dominates at high temperatures and extends down to lower temperatures. The overlap between the T-linear in-plane resistivity and the T-quadratic inverse Hall angle, if occurs, would generally present in the intermediate temperate regime. The Born-Infeld case with a 0 is quite similar to the Maxwell case. For the Born-Infeld case with a 0, there can be a constraint on the charge density and magnetic field. Moreover, the overlap can occur for strong charge density.  相似文献   
74.
张正阶  汪克林  秦敢 《中国物理》2005,14(7):1317-1322
以一个与玻色场耦合的二能级粒子为例,证实了在静态极化子问题的研究中取得成功的相干态近似方法,同样也能够有效地用于非旋波近似下量子系统的时间演化问题。结果同时表明,在一般情况下,哈密顿算符中的非旋波项不能被忽略;并提供了在频率空间进一步检测非旋波项效应的可能性。  相似文献   
75.
徐晨 《数学研究》1998,31(3):312-318
本文讨论半马氏环境连续时间马氏决策过程中的平均准则.首先讨论了半马氏报酬过程中的逼近问题,进而讨论平均目标函数逼近问题。  相似文献   
76.
设计了一款可用于触发和自触发的针板型电晕稳定开关,其中针电极直径为2 mm,主间隙距离为10 mm,触发间隙为5 mm。通过静电场的模拟得知其场强的不均匀系数大于7,并且通过大量实验数据得出:开关起晕电压和击穿电压分别为6.8 kV和19.3 kV,由此得知电晕稳定开关的电晕稳定因子为0.55,这说明开关具有较好的电晕稳定性。  相似文献   
77.
Spectrally selective splitters with metal-dielectric-metal (MDM) subwavelength waveguides are proposed in this paper. The method is based on the Bragg grating structure with periodically modulated MDM waveguide width, which delivers a stop band effect for the surface plasmon propagating in the waveguide. By adding appropriate Bragg grating structure in one or more arms of the waveguide splitters, light in a certain frequency range can be readily guided into the desired directions, as demonstrated numerically by the finite-difference time-domain method. Dependence and optimization of the geometrical parameters are also considered in this paper.  相似文献   
78.
The α-Cr2O3 single-crystal nanocondensates were fabricated by pulsed laser ablation in air and characterized by analytical electron microscopy regarding shape-dependent local internal stress of the anisotropic crystal. The nanocondensates formed predominantly as rhombohedra with well-developed surfaces and occasionally hexagonal plate with thin edges and blunt corners. Such nanocondensates showed Raman shift for the CrO6 polyhedra, indicating a local compressive stress up to ca. 4 GPa on the average. Careful analysis of the lattice fringes revealed a local compressive stress (0.5% strain) at the thin edge of the hexagonal plates and a local tensile stress (0.3–1.0% strain) near the relaxed , , and (0 0 0 1) surfaces of truncated rhombohedra. The combined effects of nanosize, capillarity force at sharp edge, and specific surface relaxation account for the retention of a local internal compressive stress built up in an anisotropic crystal during a very rapid heating–cooling process.  相似文献   
79.
By swapping the entanglement of genuine four-particle entangled states, we propose a bidirectional quantum secure communication protocol. The biggest merit of this protocol is that the information leakage does not exist. In addition, the ideas of the ``two-step" transmission and the block transmission are employed in this protocol. In order to analyze the security of the second sequence transmission, decoy states are used.  相似文献   
80.
By swapping the entanglement of genuine four-particle entangled states, we propose a bidirectional quantum secure communication protocol. The biggest merit of this protocol is that the information leakage does not exist. In addition, the ideas of the "two-step" transmission and the block transmission are employed in this protocol. In order to analyze the security of the second sequence transmission, decoy states are used.  相似文献   
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