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Nonlocal Kuramoto-Sivashinsky方程渐近吸引子的构造 被引量:1
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作者 罗宏 《湖南师范大学自然科学学报》 CAS 北大核心 2010年第3期7-12,共6页
研究了Nonlocal Kuramoto-Sivashinsky方程解的长时间行为.利用正交分解法构造了方程的一个有限维解序列,证明了该解序列在长时间后无限趋近方程的整体吸引子,并得到了渐近吸引子的维数估计.
关键词 nonlocal KURAMOTO-SIVASHINSKY方程 解序列 渐近吸引子 维数估计
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Parametric modeling of carbon nanotubes and estimating nonlocal constant using simulated vibration signals-ARMA and ANN based approach 被引量:1
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作者 Saeed Lotfan Reza Fathi 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期461-472,共12页
Nonlocal continuum mechanics is a popular growing theory for investigating the dynamic behavior of Carbon nanotubes(CNTs).Estimating the nonlocal constant is a crucial step in mathematical modeling of CNTs vibration b... Nonlocal continuum mechanics is a popular growing theory for investigating the dynamic behavior of Carbon nanotubes(CNTs).Estimating the nonlocal constant is a crucial step in mathematical modeling of CNTs vibration behavior based on this theory.Accordingly,in this study a vibration-based nonlocal parameter estimation technique,which can be competitive because of its lower instrumentation and data analysis costs,is proposed.To this end,the nonlocal models of the CNT by using the linear and nonlinear theories are established.Then,time response of the CNT to impulsive force is derived by solving the governing equations numerically.By using these time responses the parametric model of the CNT is constructed via the autoregressive moving average(ARMA)method.The appropriate ARMA parameters,which are chosen by an introduced feature reduction technique,are considered features to identify the value of the nonlocal constant.In this regard,a multi-layer perceptron(MLP)network has been trained to construct the complex relation between the ARMA parameters and the nonlocal constant.After training the MLP,based on the assumed linear and nonlinear models,the ability of the proposed method is evaluated and it is shown that the nonlocal parameter can be estimated with high accuracy in the presence/absence of nonlinearity. 展开更多
关键词 nonlocal theory nonlocal parameter estimation autoregressive moving average artificial neural network feature reduction
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Nonlocal Kuramoto-Sivashinsky方程近似惯性流形的构造
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作者 罗宏 《重庆理工大学学报(自然科学)》 CAS 2010年第9期89-93,共5页
研究了Nonlocal Kuramoto-Sivashinsky方程解的长时间行为,利用压缩映像原理,构造了方程的近似惯性流形,并得到了近似惯性流形逼近方程全局吸引子的阶数估计。
关键词 nonlocal KURAMOTO-SIVASHINSKY方程 近似惯性流形 压缩映像原理 阶数估计
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Static and dynamic stability responses of multilayer functionally graded carbon nanotubes reinforced composite nanoplates via quasi 3D nonlocal strain gradient theory
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作者 Ahmed Amine Daikh Mohamed Sid Ahmed Houari +2 位作者 Mohamed Ouejdi Belarbi Salwa A.Mohamed Mohamed A.Eltaher 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第10期1778-1809,共32页
This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)nano... This manuscript presents the comprehensive study of thickness stretching effects on the free vibration,static stability and bending of multilayer functionally graded(FG)carbon nanotubes reinforced composite(CNTRC)nanoplates.The nanoscale and microstructure influences are considered through a modified nonlocal strain gradient continuum model.Based on power-law functions,four different patterns of CNTs distribution are considered in this analysis,a uniform distribution UD,FG-V CNTRC,FG-X CNTRC,and FG-O CNTRC.A 3D kinematic shear deformation theory is proposed to include the stretching influence,which is neglected in classical theories.Hamilton's principle is applied to derive the governing equations of motion and associated boundary conditions.Analytical solutions are developed based on Galerkin method to solve the governing equilibrium equations based on the generalized higher-order shear deformation theory and the nonlocal strain gradient theory and get the static bending,buckling loads,and natural frequencies of nanoplates.Verification with previous works is presented.A detailed parametric analysis is carried out to highlight the impact of thickness stretching,length scale parameter(nonlocal),material scale parameter(gradient),CNTs distribution pattern,geometry of the plate,various boundary conditions and the total number of layers on the stresses,deformation,critical buckling loads and vibration frequencies.Many new results are also reported in the current study,which will serve as a benchmark for future research. 展开更多
关键词 3D shear deformation theory Free vibration Buckling Bending Galerkin method Functionally graded nanotube nonlocal strain gradient theory
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Hadronic contribution from light by light processes in(g-2) of muon in nonlocal quark model
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作者 ZHEVLAKOV A.S. DOROKHOV A.E. RADZHABOV A.E. 《中国科学技术大学学报》 CAS CSCD 北大核心 2016年第6期456-461,共6页
The hadronic corrections to the muon anomalous magnetic moment αμ,due to the full gaugeinvariant set of diagrams with dynamical quark loop and intermediate pseudoscalar and scalar states lightby-light scattering ins... The hadronic corrections to the muon anomalous magnetic moment αμ,due to the full gaugeinvariant set of diagrams with dynamical quark loop and intermediate pseudoscalar and scalar states lightby-light scattering insertions,are calculated in the framework of the nonlocal chiral quark model. These diagrams correspond to all hadronic light-by-light scattering contributions to α_μ in the leading order of the1 / N_c expansion in quark model. The result of the quark loop contribution is α_μ^(HLbL,Loop)=(11. 0 ± 0. 9) ·10^(-10),and the total result is α_μ^(HLbL,Loop)=(16.8 ± 1.2) ·10^(-10). 展开更多
关键词 anomalous magnetic moment of muon nonlocal model light-by-light chiral model
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后处理在数字抠像中的应用与解析 被引量:4
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作者 姚桂林 刘绍辉 +2 位作者 李敏 姚鸿勋 胡文 《电子学报》 EI CAS CSCD 北大核心 2017年第3期719-729,共11页
数字抠像是将一幅图像中的前景物体与背景进行分离的问题,它的关键在于Alpha通道的计算.以往通过采样方法求得的Alpha中,由于采用逐点计算的离散化方式,求解出的Alpha通常不连续,并且包含很多噪声,因而需要对Alpha进行后处理,这不仅会增... 数字抠像是将一幅图像中的前景物体与背景进行分离的问题,它的关键在于Alpha通道的计算.以往通过采样方法求得的Alpha中,由于采用逐点计算的离散化方式,求解出的Alpha通常不连续,并且包含很多噪声,因而需要对Alpha进行后处理,这不仅会增强Alpha在视觉上的平滑性,而且能够进一步提高Alpha的精确度.在目前国际上,有关数字抠像后处理领域已经进行了许多研究,但缺少相关的综述性文献,并且对后处理后的Alpha如何进行定量的评价也仍未系统解决.本文首先将数字抠像中的后处理方法分为2类:与仿射类方法相结合的方式及自平滑方式,其次,对两类方法进行了全面的总结和梳理,并对方法的优缺点进行了分析,对将来研究方向提出了建议,最后,针对后处理后的Alpha结果进行了全面的量化比较,弥补了传统方法基本上仅在视觉层面上进行比较的缺陷. 展开更多
关键词 图像分割 图像抠像 后处理 Laplacian抠像矩阵 nonlocal方法 自平滑
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Quantum key distribution and controlled quantum direct communication applying product state of qutrit 被引量:20
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作者 ZHU Ai-dong ZHANG Shou 《量子电子学报》 CAS CSCD 北大核心 2007年第3期316-322,共7页
On basis of the nonlocality without entanglement proposed by Bennett,the properties of an orthogonal set of product states of two qutrits are revealed,i.e.,the transformation among different composite spaces can be re... On basis of the nonlocality without entanglement proposed by Bennett,the properties of an orthogonal set of product states of two qutrits are revealed,i.e.,the transformation among different composite spaces can be realized by using three unitary operations,and the correlation between two composite spaces is found.These properties can be used to quantum communication and quantum cryptography.As examples,we propose a scheme of controlled quantum secure direct communication and one of quantum key distribution.It is shown that applying the product state of qutrit to quantum information processing not only is of the advantages of large capacity and high efficiency,but ensures the security. 展开更多
关键词 quantum information nonlocalITY QUTRIT product state quantum communication quantum key distribution
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Mechanical analysis of double-layered circular graphene sheets as building material embedded in an elastic medium 被引量:1
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作者 WU Zheng-tian HU Fu-yuan +2 位作者 ZHANG Yang GAO Qing CHEN Zhen-ping 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第11期2717-2724,共8页
Possessing the unique and highly valuable properties, graphene sheets(GSs) have attracted increasing attention including that from the building engineer due to the fact that Graphene can be utilized to reinforce concr... Possessing the unique and highly valuable properties, graphene sheets(GSs) have attracted increasing attention including that from the building engineer due to the fact that Graphene can be utilized to reinforce concrete and other building materials. In this work, the nonlocal elastic theory and classical plate theory(CLPT) are used to derive the governing equations. The element-free framework for analyzing the buckling behaviors of double layer circular graphene sheets(DLCGSs) relying on an elastic medium is proposed. Pasternak-type model is adopted to describe the elastic medium. Accordingly, the influences of boundary conditions, size of GSs and nonlocal parameters on the buckling behavior of DLCGSs are investigated. The results show that the OP buckling modes are only sensible to the van der Waals forces. 展开更多
关键词 nonlocal ELASTICITY theory double layer CIRCULAR graphene SHEETS (DLCGS) element-free method BUCKLING analysis Pasternak model
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基于非局部理论在移动力作用下Euler-Bernoulli纳米梁的动态响应(英文)
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作者 雷东侠 霍占磊 欧志英 《应用数学和力学》 CSCD 北大核心 2015年第S1期44-52,共9页
Based on the nonlocal beam theory,the dynamic behavior of simply supported Euler-Bernoulli nano-beams subjected to moving loads was studied.T he governing equations of motion for the dynamic responses of the nano-beam... Based on the nonlocal beam theory,the dynamic behavior of simply supported Euler-Bernoulli nano-beams subjected to moving loads was studied.T he governing equations of motion for the dynamic responses of the nano-beam under nonlocal effects were derived by according to Eringen’s theory.T he analytical solution to the differential equations was obtained with the state-space method.The effects of the nonlocal stresses and the magnitude of the moving force velocity on the dynamic responses of the nanobeam were discussed in detail.T he results indicate that the nonlocal effects and moving force velocity play a significant role on the dynamic mechanical responses of nano-beams. 展开更多
关键词 simply SUPPORTED beam nonlocal theory MOVING FORCE
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Higher-order electroelastic modelling of piezoelectric cylindrical nanoshell on elastic matrix
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作者 Xiao-ping Huang Peng-fei Hu Mohammad Arefi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第5期781-796,共16页
This paper develops electro-elastic relations of functionally graded cylindrical nanoshell integrated with intelligent layers subjected to multi-physics loads resting on elastic foundation.The piezoelectric layers are... This paper develops electro-elastic relations of functionally graded cylindrical nanoshell integrated with intelligent layers subjected to multi-physics loads resting on elastic foundation.The piezoelectric layers are actuated with external applied voltage.The nanocore is assumed in-homogeneous in which the material properties are changed continuously and gradually along radial direction.Third-order shear deformation theory is used for the description of kinematic relations and electric potential distribution is assumed as combination of a linear function along thickness direction to show applied voltage and a longitudinal distribution.Electro-elastic size-dependent constitutive relations are developed based on nonlocal elasticity theory and generalized Hooke’s law.The principle of virtual work is used to derive governing equations in terms of four functions along the axial and the radial directions and longitudinal electric potential function.The numerical results including radial and longitudinal displacements are presented in terms of basic input parameters of the integrated cylindrical nanoshell such as initial electric potential,small scale parameter,length to radius ratio and two parameters of foundation.It is concluded that both displacements are increased with an increase in small-scale parameter and a decrease in applied electric potential. 展开更多
关键词 Higher-order shear deformation theory Electro-elastic bending Functionally graded materials Size-dependent analysis nonlocal parameter Cylindrical nano shell
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