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1.
Zhi Zhang Xin Huang Yebin Chen Jianping Zhou 《International Journal of Adaptive Control and Signal Processing》2021,35(8):1438-1453
This article deals with the issue of input-to-state stabilization for recurrent neural networks with delay and external disturbance. The goal is to design a suitable weight-learning law to make the considered network input-to-state stable with a predefined -gain. Based on the solution of linear matrix inequalities, two schemes for the desired learning law are presented via using decay-rate-dependent and decay-rate-independent Lyapunov functionals, respectively. It is shown that, in the absence of external disturbance, the proposed learning law also guarantees the exponential stability of the network. To illustrate the applicability of the present weight-learning law, two numerical examples with simulations are given. 相似文献
2.
Bo Wu Huiying Du Ping Hu Zhanyu Gao Ruikai Liu Chonghua Pei 《Journal of Energetic Materials》2021,39(1):10-22
ABSTRACT In recent years, the exploration of a practical strategy for novel energetic molecules with high energy and low sensitivity is very desirable but highly challenging. Novel ionic energetic molecules have attracted much attention in this area due to their prominent advantages including low sensitivities, high thermal stability, and excellent energy performances. Herein, five different ionic energetic molecules based on new monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties with enhanced oxygen balance have been synthesized, characterized and evaluated as potential high-energy materials. Thermal stability, sensitivities and energy output test were measured and studied in detail. The heats of formation and energetic parameters were calculated by using Gaussian 09 suite of programs and EXPLO 5 code. The results suggest that all as-prepared new molecules exhibit good thermal stability with high decomposition temperature (3, 231°C; 5, 160°C; 6, 185°C; 7, 180°C; 8, 213°C), and relative low sensitivity (IS > 20 J, FS = 324 N). Inheriting the significant oxygen content of monovalent and divalent 4-oxyl-3,5-dinitropyrazolate moieties, they also possess good energy properties (v D = 8238 ~ 9208 m s?1, P = 26.8 ~ 36.7 GPa, V o = 481.8 ~ 959.4 L kg?1), which make them competitive high-energy materials. 相似文献
3.
Anis Zeglaoui Anouar Houmia Maher Mejai Radhouane Aloui 《International Journal of Adaptive Control and Signal Processing》2021,35(9):1842-1859
In compressive sampling theory, the least absolute shrinkage and selection operator (LASSO) is a representative problem. Nevertheless, the non-differentiable constraint impedes the use of Lagrange programming neural networks (LPNNs). We present in this article the -LPNN model, a novel algorithm that tackles the LASSO minimization together with the underlying theory support. First, we design a sequence of smooth constrained optimization problems, by introducing a convenient differentiable approximation to the non-differentiable -norm constraint. Next, we prove that the optimal solutions of the regularized intermediate problems converge to the optimal sparse signal for the LASSO. Then, for every regularized problem from the sequence, the -LPNN dynamic model is derived, and the asymptotic stability of its equilibrium state is established as well. Finally, numerical simulations are carried out to compare the performance of the proposed -LPNN algorithm with both the LASSO-LPNN model and a standard digital method. 相似文献
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本文通过对长江三峡黄陵结晶岩区的地质条件、斜坡分级、各类斜坡的分布特征及成因类型等方面的系统论述,综合评价结晶岩区各类斜坡的宏观稳定性与稳定性分区,从而达到对该区斜坡合理开发与综合利用的目的。 相似文献
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本文总结了声发射现场监测预报的试验结果,提出了采场稳定性预测的综合方法,应用灰色理论预测和神经网络方法较好地解决了采场冒顶预报问题。 相似文献
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近年来,门式刚架在工业厂房的设计中得到广泛的应用。对于一般的轻型门式刚架,通过设置隅撑来保证屋面梁受压下翼缘的平面外稳定,经多年的工程实践已经被证明是一种行之有效的构造措施。但对于大跨度、屋面荷载比较大的建筑物,经实例分析,如果仍采用这一措施则很难达到预期的效果。为保证结构的安全性和可靠性,探讨了一种行之有效的解决方案———摇摆支撑的设置。 相似文献
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