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11.
一、引言 观测托卡马克装置中等离子体引起的极向磁场扰动,通常把测得的磁扰动信号用电子学线路进行模拟量处理或计算机系统作数字量处理,如相关分析,空间付利叶分析等,以辨别各种扰动模式及其随时间的演化。用这些方法监测放电准稳阶段的磁流体扰动,已属常 相似文献
12.
讨论由Young函数生成的Orlicz空间L*_Φ(0,∞)的性质,并给出Orlicz空间L*_Φ(0,∞)具有Hardy-Littlewood性质的充要条件,然后借助加Jacobi权修正的K-泛函和加Jacobi权连续模及其等价性建立Gamma算子在Orlicz空间L*_Φ(0,∞)中加权同时逼近的两种强逆不等式. 相似文献
13.
14.
胡适耕 《高校应用数学学报(A辑)》1994,(4):391-400
本文对定义于一定有序局部紧空间上的向量值函数建立一个Bihari型积分不等式,并给出其对于非线性Volterra型积分方程的若干应用。 相似文献
15.
By analyzing the radiation dose on PIN photodetectors in space radiation environment, the variation of photocurrent and dark current after radiation is obtained. On the basis, the bit error rate of satellite laser communication based on space radiation dose of PIN photodetectors is established. According to simulation, when radiation dose is about 1.6 × 103 Gy and 7 × 104 Gy, bit error rate reaches 10−6 induced by 50 MeV and 10 MeV protons separately; and when radiation dose is within the range of 5 × 10 Gy–6 × 105 Gy, electrons and gamma-ray irradiation also cause increase in bit error rate to 10−6. The principle of damage dose on bit error rate is investigated, and the influence of decision threshold on bit error rate is further discussed. The result shows that when radiation dose is 1 MGy, if decision threshold is increased from 4.3 × 10−7 A to 5.5 × 10−7 A, bit error rate will decrease about 4 orders of magnitude. Hence, a proper decision threshold can improve system bit error rate efficiently. 相似文献
16.
《Mathematische Nachrichten》2018,291(2-3):492-517
We study the existence of nonnegative and nonzero solutions for the following class of quasilinear Schrödinger equations: where V and Q are potentials that can be singular at the origin, unbounded or vanishing at infinity. In order to prove our existence result we used minimax techniques in a suitable weighted Orlicz space together with regularity arguments and we need to obtain a symmetric criticality type result. 相似文献
17.
用激光诱导荧光(LIF)方法对芳香族化合物蒽进行了时间分辨谱研究,介绍了所用测试系统的组成和测试方法,获得了蒽的荧光强度-波长-时间三维立体图、峰值荧光时间图、等高图,并对实验结果进行了分析。研究表明,荧光产生的时间与峰值波长有关系,长波早于短波。 相似文献
18.
M.K. Kuo T.R. Lin B.T. Liao C.H. Yu 《Physica E: Low-dimensional Systems and Nanostructures》2005,26(1-4):199
Strain distribution and optical properties in a self-assembled pyramidal InAs/GaAs quantum dot grown by epitaxy are investigated. A model, based on the theory of linear elasticity, is developed to analyze three-dimensional induced strain field. In the model, the capping material in the heterostructure is omitted during the strain analysis to take into account the sequence of the fabrication process. The mismatch of lattice constants is the driving source of the induced strain and is treated as initial strain in the analysis. Once the strain analysis is completed, the capping material is added back to the heterostructure for electronic band calculation. The strain-induced potential is incorporated into the three-dimensional steady-state Schrödinger equation with the aid of Pikus–Bir Hamiltonian with modified Luttinger–Kohn formalism for the electronic band structure calculation. The strain field, the energy levels and wave functions are found numerically by using of a finite element package FEMLAB. The energy levels as well as the wave functions of both conduction and valence bands of quantum dot are calculated. Finally, the transition energy of ground state is also computed. Numerical results reveal that not only the strain field but also all other optical properties from current model show significant difference from the counterparts of the conventional model. 相似文献
19.
Some necessary and sufficient conditions for a Banach space to be K-smooth or Kstrongly smooth are obtained. 相似文献
20.
Various theories of Quantum Gravity predict modifications of the Heisenberg Uncertainty Principle near the Planck scale to a so-called Generalized Uncertainty Principle (GUP). In some recent papers, we showed that the GUP gives rise to corrections to the Schrödinger equation, which in turn affect all quantum mechanical Hamiltonians. In particular, by applying it to a particle in a one-dimensional box, we showed that the box length must be quantized in terms of a fundamental length (which could be the Planck length), which we interpreted as a signal of fundamental discreteness of space itself. In this Letter, we extend the above results to a relativistic particle in a rectangular as well as a spherical box, by solving the GUP-corrected Klein–Gordon and Dirac equations, and for the latter, to two and three dimensions. We again arrive at quantization of box length, area and volume and an indication of the fundamentally grainy nature of space. We discuss possible implications. 相似文献