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Coupled DEM-FDM analyses of the effects of falling rock’s shape and impact angle on response of granular cushion and rock shed
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作者 Jingyu Xue Chen Cao +2 位作者 Jianhua Yan Yaopeng Ji Jianping Chen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第8期3353-3364,共12页
Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed... Rock shed is an effective protection measure against rockfall.To investigate the influences of falling rock’s shape and impact angle on the impact effect of the cushioned rock shed,a modeling approach for a rock shed with a cushion layer using PFC-FLAC.The granular cushion is modeled as an aggregate of discrete non-cohesion particles,while the concrete plate and the beam are modeled as zones.The falling rock with different sphericities and impact angles is modeled as a rigid assembly.The numerical model is validated by comparing the simulation results with experimental and numerical results from previous literature.This model is applied to analyze the effects of rock shape and impact angle on the dynamic interaction effects between falling rock and cushioned rock shed,including the impact force,transmitted bottom force,penetration depth,and plate deflection.The numerical results show that the variation in the falling rock’s shape has different effects on the falling rock with different impact angles.These findings could support rock shed design by revealing the limitations of the assumptions in the past research,which may result in unsafe rock sheds for some rockfall cases. 展开更多
关键词 Rockfall coupled DEM-FDM analysis Rock’s shape Impact angle Granular cushion Rock shed
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Fractional Noether theorem and fractional Lagrange equation of multi-scale mechano-electrophysiological coupling model of neuron membrane
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作者 王鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期409-415,共7页
Noether theorem is applied to a variable order fractional multiscale mechano-electrophysiological model of neuron membrane dynamics.The variable orders fractional Lagrange equation of a multiscale mechano-electrophysi... Noether theorem is applied to a variable order fractional multiscale mechano-electrophysiological model of neuron membrane dynamics.The variable orders fractional Lagrange equation of a multiscale mechano-electrophysiological model of neuron membrane dynamics is given.The variable orders fractional Noether symmetry criterion and Noether conserved quantities are given.The forms of variable orders fractional Noether conserved quantities corresponding to Noether symmetry generators solutions of the model under different conditions are discussed in detail,and it is found that the expressions of variable orders fractional Noether conserved quantities are closely dependent on the external nonconservative forces and material parameters of the neuron. 展开更多
关键词 Hamilton’s principle Noether theorem fractional derivative multiscale electromechanical coupling neuron membrane
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Unity Formulas for the Coupling Constants and the Dimensionless Physical Constants
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作者 Stergios Pellis 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2023年第1期245-294,共50页
In this paper in an elegant way will be presented the unity formulas for the coupling constants and the dimensionless physical constants. We reached the conclusion of the simple unification of the fundamental interact... In this paper in an elegant way will be presented the unity formulas for the coupling constants and the dimensionless physical constants. We reached the conclusion of the simple unification of the fundamental interactions. We will find the formulas for the Gravitational constant. It will be presented that the gravitational fine-structure constant is a simple analogy between atomic physics and cosmology. We will find the expression that connects the gravitational fine-structure constant with the four coupling constants. Perhaps the gravitational fine-structure constant is the coupling constant for the fifth force. Also will be presented the simple unification of atomic physics and cosmology. We will find the formulas for the cosmological constant and we will propose a possible solution for the cosmological parameters. Perhaps the shape of the universe is Poincare dodecahedral space. This article will be followed by the energy wave theory and the fractal space-time theory. 展开更多
关键词 Fine-structure Constant Proton To Electron Mass Ratio Dimensionless Physical Constants coupling Constant Gravitational Constant Avogadro’s Number Fundamental Interactions Gravitational Fine-structure Constant Cosmological Constant
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Studies on the structure and catalytic performance of S and P promoted Na-W-Mn-Zr/SiO_2 catalyst for oxidative coupling of methane 被引量:5
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作者 Wen Zheng, Dangguo Cheng, Ning Zhu, Fengqiu Chen, Xiaoli Zhan Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou 310027, Zhejiang, China 《Journal of Natural Gas Chemistry》 CSCD 2010年第1期15-20,共6页
A series of Na-W-Mn-Zr/SiO2 catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on t... A series of Na-W-Mn-Zr/SiO2 catalysts promoted by different contents of S or/and P were prepared and their catalytic performance for oxidative coupling of methane was investigated to clarify the effect of S and P on the Na-W-Mn-Zr/SiO2 catalyst. The catalysts were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). From the characterization results, it is found that the addition of S and P to the Na-W-Mn-ZffSiO2 catalyst helps the formation of active phases, such as α-cristobalite, Na2WO4, ZrO2, and Na2SO4. Moreover, the addition of S and P increases the concentration of surface-active oxygen species by improving the migration of active components from the bulk phase to the surface of the catalyst. According to the activity test, impressive methane conversion and C2 hydrocarbons yield were obtained at a low temperature of 1023 K over the six-component Na-W-Mn-Zr-S-P/SiO2 catalyst, which contained 2 wt% S and 0.4 wt% P simultaneously. The deactivation of Na-W-Mn-Zr-S-P/SiO2 was due to the loss of surface active components. 展开更多
关键词 oxidative coupling of methane Na-W-Mn-Zr/siO2 s P
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Decoupling Conditions for Elasto-plastic Consolidation Question Based on Numerical Modeling Method 被引量:1
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作者 Cheng Tao Wang Jingtao Dong Bichang 《Journal of China University of Geosciences》 SCIE CSCD 2005年第4期363-368,共6页
Elasto-plastic consolidation is one of the classic coupling questions in geomechanics. To solve this problem, an elasto-plastic constitutive model is derived based on the numerical modeling method. The model is applie... Elasto-plastic consolidation is one of the classic coupling questions in geomechanics. To solve this problem, an elasto-plastic constitutive model is derived based on the numerical modeling method. The model is applied to Blot's consolidation theory. Incremental governing partial differential equations are established using this method. According to the stress path, the decoupling condition of these equations is discussed. Based on these conditions, an incremental diffusion equation and uncoupling governing equations are presented. The method is then applied to numerical analyses of three examples. The results show that (1) the effect of the stress path should be taken into account in the simulation of the soil consolidation question; (2) this decoupling method can predict the evolvement of pore water pressure; (3) the settlement using cam-clay model is less than that using numerical model because of dilatancy. 展开更多
关键词 numerical modeling method Blot's consolidation stress path constitutive model liquisolid coupling decouple incremental diffusion equation dilatancy.
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Unified Equation of Fundamental Forces’ Coupling Values, and the Existence of Subsequent, Fifth and Other, Forces 被引量:2
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作者 Kaveh Mozafari 《Journal of Applied Mathematics and Physics》 2022年第8期2499-2507,共9页
This paper provides an equation to entangle all known fundamental forces by employing their coupling constants, i.e., strong (α<sub>s</sub>), electromagnetic (α), weak (α<sub>w</sub>), and g... This paper provides an equation to entangle all known fundamental forces by employing their coupling constants, i.e., strong (α<sub>s</sub>), electromagnetic (α), weak (α<sub>w</sub>), and gravitational (α<sub>g</sub>) interaction coupling values. The constant coupling formulation is further indicative of many other fundamental forces with significantly weaker coupling values. As an example, the fifth fundamental force, Kashi’s Force, is found to have a coupling constant of 10<sup>-1446</sup>, which is significantly smaller than the smallest known fundamental force, gravitational force, with an approximate coupling constant value of 10<sup>-38</sup>. Additionally, the paper finds the sum of all fundamental forces based on the equation proposed is equal to 0.118065, which is within the range of effective world value of the strong coupling constant α<sub>s</sub>(M<sup>2</sup>z</sub>). 展开更多
关键词 Fundamental Forces coupling Value Kashi’s Force Unified Equation
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Relations Between Helicity Coupling Amplitude and L—S Coupling Amplitude 被引量:1
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作者 WUNing RUANTu-Nan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2001年第6期693-696,共4页
Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also stu... Relations between helicity coupling amplitude and L-S coupling amplitude are discussed. The equivalence condition for these two kinematic analysis methods and the limitations of the L-S coupling amplitude are also studied in this paper. 展开更多
关键词 高能物理 手征性耦合振幅 L-s耦合振幅
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Characterization and catalytic behavior of Na-W-Mn-Zr-S-P/SiO_2 prepared by different methods in oxidative coupling of methane 被引量:2
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作者 Wen Zheng Dangguo Cheng Fengqiu Chen Xiaoli Zhan 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第5期515-521,共7页
Na-W-Mn-Zr-S-P/SiO2 catalysts for oxidative coupling of methane (OCM) were prepared by incipient wetness impregnation, sol-gel and mixture slurry methods. The catalyst prepared by mixture slurry method showed the be... Na-W-Mn-Zr-S-P/SiO2 catalysts for oxidative coupling of methane (OCM) were prepared by incipient wetness impregnation, sol-gel and mixture slurry methods. The catalyst prepared by mixture slurry method showed the best catalytic performance among all samples. In addition, the effects of different addition sequences of Na, W, Mn, Zr, S and P on the catalytic performance were studied. The absence of Na before the addition of Mn and Zr in the catalysts preparation depressed the formation of the active phases of Mn2O3 and ZrO2 and decreased the activities of the catalysts significantly. 展开更多
关键词 oxidative coupling of methane Na-W-Mn-Zr-s-P/siO2 prepared method
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A Finite Element Procedure for Analysis of Chemo-Mechanical Coupling Behavior of Hydrogels
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作者 Wei Wei Qingsheng Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2016年第7期33-58,共26页
Chemo-mechanical coupling behavior of materials is a transformation process between mechanical and chemical energy.In this paper,based on the coupled chemo-mechanical constitutive equations and governing equations dur... Chemo-mechanical coupling behavior of materials is a transformation process between mechanical and chemical energy.In this paper,based on the coupled chemo-mechanical constitutive equations and governing equations during isothermal process,the equivalent integral forms of chemo-mechanical coupling governing equations and corresponding finite element procedure are obtained by using Hamilton’s principle.An isoparametric plane element for chemo-mechanical coupling is associated into ABAQUS finite element package through user element subroutine UEL.The numerical examples exhibit that the ionic concentration variation can cause mechanical deformation and mechanical action can produce redistribution of ionic concentration for hydrogels.It is proved that the present developed chemo-mechanical coupling finite element procedure can be utilized to model the coupling behavior of hydrogels effectively. 展开更多
关键词 HYDROGEL Chemo-mechanical coupling Hamilton’s PRINCIPLE coupled FINITE element method
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Green Synthesis of Aryl Thioethers through Cu-catalysed C-S Coupling of Thiols and Aryl Boronic Acids in Water 被引量:1
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作者 涂佩华 JIANG Jun +1 位作者 XIAO Hongping 李新华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第4期987-993,共7页
An efficient, practical, highly selective and environmentally benign method is reported for the synthesis of aryl thioethers via the coupling of thiols with aryl boronic acids in the presence of NaOH and a catalytic a... An efficient, practical, highly selective and environmentally benign method is reported for the synthesis of aryl thioethers via the coupling of thiols with aryl boronic acids in the presence of NaOH and a catalytic amount of CuSO4 at 130 ℃ using water as a green solvent. The products were obtained in moderate to excellent yields;more importantly, the use of toxic ligands and solvents was avoided. A broad range of aryl boronic acids and scalable processes make this methodology valuable and versatile for the synthesis of a broad range of aryl sulfides. 展开更多
关键词 green synthesis Cu-catalysed C-s coupling ARYL boronic acids WATER solvent ARYL thioether
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Holographic superconductor models in the non-minimal derivative coupling theory
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作者 陈松柏 潘启沅 荆继良 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期126-133,共8页
We study a general class of holographic superconductor models via the Stiickelberg mechanism in the non-minimal derivative coupling theory in which the charged scalar field is kinetically coupling to Einstein's tenso... We study a general class of holographic superconductor models via the Stiickelberg mechanism in the non-minimal derivative coupling theory in which the charged scalar field is kinetically coupling to Einstein's tensor. We explore the effects of the coupling parameter on the critical temperature, the order of phase transitions and the critical expo- nents near the second-order phase transition point. Moreover, we compute the electrical conductivity using the probe approximation and check the ratios wg/Tc for the different coupling parameters. 展开更多
关键词 holographic superconductor non-minimal derivative coupling Einstein's tensor
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The Tension Cosmology, Largest Cosmic Structures and Explosions of Supernovae from SST
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作者 Sylwester Kornowski 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1029-1044,共16页
Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter lea... Here, using the Scale-Symmetric Theory (SST) we explain the cosmological tension and the origin of the largest cosmic structures. We show that a change in value of strong coupling constant for cold baryonic matter leads to the disagreement in the galaxy clustering amplitude, quantified by the parameter S8. Within the same model we described the Hubble tension. We described also the mechanism that transforms the gravitational collapse into an explosion—it concerns the dynamics of virtual fields that lead to dark energy. Our calculations concern the Type Ia supernovae and the core-collapse supernovae. We calculated the quantized masses of the progenitors of supernovae, emitted total energy during explosion, and we calculated how much of the released energy was transferred to neutrinos. Value of the speed of sound in the strongly interacting matter measured at the LHC confirms that presented here model is correct. Our calculations show that the Universe is cyclic. 展开更多
关键词 scale-symmetric Theory Tension Cosmology coupling Constants Parameters σ8 and s8 Largest Cosmic structures Dark Energy supernova Explosion Cyclic Universe
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Two Types of Coupling Integrable Couplings of the S-mKdV Hierarchy
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作者 魏媛 张玉峰 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第2期209-212,共4页
第一, 4 谎言代数学被构造。然后,循环代数学的应用程序被介绍获得由使用 Tu 计划联合 S-mKdV 层次的 integrable couplings 的二种类型。S-mKdV 层次的联合 integrable couplings 在纸还原剂获得了到 mKdV 方程的联合 integrable cou... 第一, 4 谎言代数学被构造。然后,循环代数学的应用程序被介绍获得由使用 Tu 计划联合 S-mKdV 层次的 integrable couplings 的二种类型。S-mKdV 层次的联合 integrable couplings 在纸还原剂获得了到 mKdV 方程的联合 integrable couplings 和非线性的 Schr 的联合 integrable couplings ? dinger 方程分别地。在纸给的方法能通常习惯于另外的层次。 展开更多
关键词 耦合类型 混合层 非线性薛定谔方程 MKDV方程 层次结构 李代数 屠格式
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Impact of coupling geometry on thermoelectric properties of oligophenyl-base transistor
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作者 S Ramezani Akbarabadi H Rahimpour Soleimani +1 位作者 M Bagheri Tagani Z Golsanamlou 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第2期420-427,共8页
Thermal and electron transport through organic molecules attached to three-dimensional gold electrodes in two different configurations, namely para and meta with thiol-terminated junctions is studied theoretically in ... Thermal and electron transport through organic molecules attached to three-dimensional gold electrodes in two different configurations, namely para and meta with thiol-terminated junctions is studied theoretically in the linear response regime using Green's function formalism. We used thiol-terminated(–SH bond) benzene units and found a positive thermopower because the highest occupied molecular orbital(HOMO) is near the Fermi energy level. We investigated the influence of molecular length and molecular junction geometry on the thermoelectric properties. Our results show that the thermoelectric properties are highly sensitive to the coupling geometry and the molecular length. In addition, we observed that the interference effects and increasing molecular length can increase the thermoelectric efficiency of device in a specific configuration. 展开更多
关键词 coupling geometry figure of merit Green's function oligophenyl thermopower
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可见光氧化还原协同镍催化构建C—S键偶联反应
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作者 李申 剧芳 +2 位作者 张舒雅 丁晶晶 康舒铭 《合成化学》 CAS 2024年第5期414-423,共10页
在可见光和过渡金属镍协同催化体系中,可见光催化可以通过单电子氧化或还原过程推动过渡金属镍催化,又可以通过能量转移过程推动镍催化循环。这为传统过渡金属催化的偶联反应提供了更多可能性。同时,大多数光催化剂使用基于Ru和Ir金属... 在可见光和过渡金属镍协同催化体系中,可见光催化可以通过单电子氧化或还原过程推动过渡金属镍催化,又可以通过能量转移过程推动镍催化循环。这为传统过渡金属催化的偶联反应提供了更多可能性。同时,大多数光催化剂使用基于Ru和Ir金属的配合物,不仅价格昂贵,还会在工业生产中存在金属残留。本文开发了一种高效且经济的协同催化体剂(Nap)_(2)PXZ-bpy-Ni,以吩噁嗪为有机光催化剂,NiBr_(2)·DME为镍催化剂,联吡啶作为配体,通过Click的方式将光催化剂和联吡啶镍催化剂连接起来。实验结果表明:在1%(物质的量分数,下同)催化剂负载下反应12H,C—S键偶联产物收率可达73%~95%,实现了高效的催化效率并显示出较好的官能团适用性和底物普适性。最后通过自由基捕捉实验推测了该反应可能的机理。 展开更多
关键词 光催化 镍催化 协同催化 有机光敏剂 C—s偶联反应
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基于三次S型速度控制算法的移动机械臂末端振动研究
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作者 刘益军 李正强 +1 位作者 赖建防 吕伟宏 《机械制造与自动化》 2024年第1期232-237,共6页
移动机械臂在实际工作环境中,受其自身柔性特征和外部因素的影响而引起机械臂末端的振动,而速度控制是实现机械臂末端抑振的有效手段之一。以UR10机械臂和Husky移动平台组成的移动机械臂为研究对象,针对梯形和S型速度控制算法的不足,提... 移动机械臂在实际工作环境中,受其自身柔性特征和外部因素的影响而引起机械臂末端的振动,而速度控制是实现机械臂末端抑振的有效手段之一。以UR10机械臂和Husky移动平台组成的移动机械臂为研究对象,针对梯形和S型速度控制算法的不足,提出一种三次S型速度控制算法,通过建立移动机械臂刚柔耦合动力学的理论和仿真模型得到移动机械臂末端的振动位移曲线和加速度变化曲线,验证了三次S型速度控制算法的正确性和抑振效果的有效性。 展开更多
关键词 移动机械臂 刚柔耦合 三次s型速度控制算法
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Soliton solution and interaction property for a coupled modified Korteweg-de Vries (mKdV) system 被引量:5
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作者 杨建荣 毛杰健 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第12期4337-4343,共7页
Hirota's bilinear direct method is applied to constructing soliton solutions to a special coupled modified Korteweg- de Vries (mKdV) system. Some physical properties such as the spatiotemporal evolution, waveform s... Hirota's bilinear direct method is applied to constructing soliton solutions to a special coupled modified Korteweg- de Vries (mKdV) system. Some physical properties such as the spatiotemporal evolution, waveform structure, interactive phenomena of solitons are discussed, especially in the two-soliton case. It is found that different interactive behaviours of solitary waves take place under different parameter conditions of overtaking collision in this system. It is verified that the elastic interaction phenomena exist in this (1+1)-dimensional integrable coupled model. 展开更多
关键词 coupled mKdV system Hirota's bilinear method soliton solution elastic interaction
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The Hirota bilinear method for the coupled Burgers equation and the high-order Boussinesq-Burgers equation 被引量:2
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作者 左进明 张耀明 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第1期69-75,共7页
This paper studies the coupled Burgers equation and the high-order Boussinesq-Burgers equation. The Hirota bilinear method is applied to show that the two equations are completely integrable. Multiple-kink (soliton)... This paper studies the coupled Burgers equation and the high-order Boussinesq-Burgers equation. The Hirota bilinear method is applied to show that the two equations are completely integrable. Multiple-kink (soliton) solutions and multiple-singular-kink (soliton) solutions are derived for the two equations. 展开更多
关键词 coupled Burgers equation high-order Boussinesq-Burgers equation Hirota's bilinear method
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The Inertial Manifolds for a Class of Higher-Order Coupled Kirchhoff-Type Equations 被引量:3
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作者 Guoguang Lin Sanmei Yang 《Journal of Applied Mathematics and Physics》 2018年第5期1055-1064,共10页
In this paper, we mainly deal with a class of higher-order coupled Kirch-hoff-type equations. At first, we take advantage of Hadamard’s graph to get the equivalent form of the original equations. Then, the inertial m... In this paper, we mainly deal with a class of higher-order coupled Kirch-hoff-type equations. At first, we take advantage of Hadamard’s graph to get the equivalent form of the original equations. Then, the inertial manifolds are proved by using spectral gap condition. The main result we gained is that the inertial manifolds are established under the proper assumptions of M(s) and gi(u,v), i=1, 2. 展开更多
关键词 HIGHER-ORDER couplED Kirchhoff-Type EQUATIONs Inertial MANIFOLD Hadamard’s Graph spectral Gap Condition
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Modified two-grid method for solving coupled Navier-Stokes/Darcy model based on Newton iteration 被引量:1
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作者 SHEN Yu-jing HAN Dan-fu SHAO Xin-ping 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2015年第2期127-140,共14页
A new decoupled two-gird algorithm with the Newton iteration is proposed for solving the coupled Navier-Stokes/Darcy model which describes a fluid flow filtrating through porous media. Moreover the error estimate is g... A new decoupled two-gird algorithm with the Newton iteration is proposed for solving the coupled Navier-Stokes/Darcy model which describes a fluid flow filtrating through porous media. Moreover the error estimate is given, which shows that the same order of accuracy can be achieved as solving the system directly in the fine mesh when h = H2. Both theoretical analysis and numerical experiments illustrate the efficiency of the algorithm for solving the coupled problem. 展开更多
关键词 Navier-stokes equation Darcy's law interface coupling two-grid algorithm Newton iteration
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