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81.
作者用Si(Li)探测器测量了能量为5~2keV的电子碰撞Ag的L壳总平均电离截面;用Monte Carlo方法计算的电子反射能谱,修正了来自衬底的反射电子对测量结果的影响.作者对实验结果与Cryzinski的理论计算结果进了比较. 相似文献
82.
83.
为了消除凸规划问题中极大熵方法所导致的数值病态,该文应用Lagrange乘子法及赋范原理,给出一类凸规划问题的极大熵函数序列,并证明该序列一致收敛于凸规划的最优解。 相似文献
84.
The measure of uncertainty is adopted as a measure of information. The measures of fuzziness are known as fuzzy information measures. The measure of a quantity of fuzzy information gained from a fuzzy set or fuzzy system is known as fuzzy entropy. Fuzzy entropy has been focused and studied by many researchers in various fields. In this paper, firstly, the axiomatic definition of fuzzy entropy is discussed. Then, neural networks model of fuzzy entropy is proposed, based on the computing capability of neural networks. In the end, two examples are discussed to show the efficiency of the model. 相似文献
85.
In this Note, we return to the theory of characteristic modes which was introduced 30 years ago for electromagnetic scattering problems. A simple mathematical framework is proposed and complete definitions are given. The potential interest of this theory in terms of Radar Cross Section (RCS) analysis is then discussed, especially in the low frequency case. Finally, a 3-D example is presented to illustrate the efficiency of this decomposition. To cite this article: Y. Morel et al., C. R. Mecanique 332 (2004). 相似文献
86.
Quantization consists in studying the L
r
-error induced by the approximation of a random vector X by a vector (quantized version) taking a finite number n of values. We investigate this problem for Gaussian random vectors in an infinite dimensional Banach space and in particular, for Gaussian processes. A precise link proved by Fehringer(4) and Dereich et al.
(3) relates lower and upper bounds for small ball probabilities with upper and lower bounds for the quantization error, respectively. We establish a complete relationship by showing that the same holds for the direction from the quantization error to small ball probabilities. This allows us to compute the exact rate of convergence to zero of the minimal L
r
-quantization error from logarithmic small ball asymptotics and vice versa. 相似文献
87.
88.
Using the thermodynamical approach and the method of York, the back-reaction of anti-de Sitter Schwarzschild black hole in thermal equilibrium with conformal spin-2 field is studied. It is found that both approaches give identical results. 相似文献
89.
Elastic electron scattering on the exotic light nucleus28S is investigated in the plane wave Born approximation. The variation of the squared form factors of28S with momentum transfer is compared with that of32S. It is found that the behavior of the form factors near the second minimum (with a moderate momentum transfer) is sensitive
to the alteration of the charge density distribution of halo protons in28S. This indicates that elastic electron scattering can be a good probe of the structure of proton-halo nuclei. 相似文献
90.
在流函数具有有限个拐点,初始值为两段常数和边界值为常数的条件下,研究非凸单个守恒律的初边值问题整体弱熵解的结构、初等波与边界的相互作用情况以及弱熵解在边界附近的性态. 相似文献