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Photoinduced Floquet higher-order Weyl semimetal in C_(6) symmetric Dirac semimetals
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作者 许欣欣 王梓名 +1 位作者 许东辉 陈垂针 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期109-117,共9页
Topological Dirac semimetals are a parent state from which other exotic topological phases of matter, such as Weyl semimetals and topological insulators, can emerge. In this study, we investigate a Dirac semimetal pos... Topological Dirac semimetals are a parent state from which other exotic topological phases of matter, such as Weyl semimetals and topological insulators, can emerge. In this study, we investigate a Dirac semimetal possessing sixfold rotational symmetry and hosting higher-order topological hinge Fermi arc states, which is irradiated by circularly polarized light. Our findings reveal that circularly polarized light splits each Dirac node into a pair of Weyl nodes due to the breaking of time-reversal symmetry, resulting in the realization of the Weyl semimetal phase. This Weyl semimetal phase exhibits rich boundary states, including two-dimensional surface Fermi arc states and hinge Fermi arc states confined to six hinges.Furthermore, by adjusting the incident direction of the circularly polarized light, we can control the degree of tilt of the resulting Weyl cones, enabling the realization of different types of Weyl semimetals. 展开更多
关键词 Dirac semimetals Weyl semimetals periodic driving higher-order topology
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Higher-order expansions of powered extremes of logarithmic general error distribution
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作者 TAN Xiao-feng LI Li-hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第1期47-54,共8页
In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of nor... In this paper,Let M_(n)denote the maximum of logarithmic general error distribution with parameter v≥1.Higher-order expansions for distributions of powered extremes M_(n)^(p)are derived under an optimal choice of normalizing constants.It is shown that M_(n)^(p),when v=1,converges to the Frechet extreme value distribution at the rate of 1/n,and if v>1 then M_(n)^(p)converges to the Gumbel extreme value distribution at the rate of(loglogn)^(2)=(log n)^(1-1/v). 展开更多
关键词 logarithmic general error distribution convergence rate higher-order expansion powered ex-treme
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A Study of a Moral Dilemma Stories Teaching Model Focusing on the Development of Higher-Order Thinking --"Synthetic polymers" as an example
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作者 Lin Tang Yi Dai 《教育技术与创新》 2024年第1期27-35,共9页
Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral di... Cultivating students'higher-order thinking is one of the important goals of modern education,and innovative teaching model is an effective way to achieve this goal.Aiming at the inadequacy of the existing moral dilemma stories approach in the transformation of knowledge and behavior,this research constructs a new Project Based Learning-Ethical Dilemma Stories(PBL-EDS)Teaching Model applicable to China's secondary education stage based on the innovative features of the moral dilemma stories approach on the core competencies,taking the chemistry subject as an example to carry out practice,and puts forward suggestions for the implementation of the teaching model.Chemistry as an example to carry out the practice,and suggestions are made for the implementation of the teaching model. 展开更多
关键词 higher-order thinking moral dilemma stories teaching model secondary education
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The Importance of Setting Treatment Goals for Cardiovascular Diseases
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作者 David S. Schade Bramara Nagamallika Godasi +1 位作者 Teodor Duro Robert Philip Eaton 《World Journal of Cardiovascular Diseases》 CAS 2024年第1期10-15,共6页
Background: Guidelines are issued by most major organizations that focus on a specific disease entity. Guidelines should be a significant help to the practicing physician who may not be up-to-date with the recent medi... Background: Guidelines are issued by most major organizations that focus on a specific disease entity. Guidelines should be a significant help to the practicing physician who may not be up-to-date with the recent medical literature. Unfortunately, when conflicting guidelines for a specific disease are published, confusion results. Purpose: This article provides a suggested guideline outcome measure that would benefit the physician and patient. Methods: A review of 19 different guidelines for cardiovascular disease treatment is one example of the lack of specific outcomes that currently exist. The basic problem with most guidelines is that they do not state the expected end result (i.e., the benefit to the patient) if that guideline is followed. When guidelines use cardiovascular disease risk factors to dictate therapy, the end benefit is never stated so that the patient can make an appropriate choice of which (if any) guideline to follow. Results: A good example is guidelines published by the American Heart Association for reducing cardiovascular disease. These guidelines are risk factor based and only indicate that cardiovascular disease would be reduced if followed. No specific percentage in the reduction of the incidence of disease is given. In contrast, when elimination of the disease is the stated goal of the guideline, the end result is clear. To date, this goal has been stated by only one organization devoted to eliminating cardiovascular disease. Conclusion: Guidelines need to be written to provide the physician and the patient with a specific end point that is expected when the guideline is followed. Patient acceptance and compliance will be much improved if the patient knows the risk/benefit of following the guideline’s recommendations. 展开更多
关键词 Guideline goals for Cardiovascular Disease Prevention Cardiovascular Disease Risk Factors for Cardiovascular Disease Pooled Cohort Equations
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Spatial differences of Sustainable Development Goals(SDGs)among counties(cities)on the northern slope of the Kunlun Mountains
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作者 WANG Tao ZHOU Daojing FAN Jie 《Regional Sustainability》 2024年第1期1-10,共10页
The county(city)located on the northern slope of the Kunlun Mountains is the primary area to solidify and extend the success of Xinjiang Uygur Autonomous Region,China in poverty alleviation.Its Sustainable Development... The county(city)located on the northern slope of the Kunlun Mountains is the primary area to solidify and extend the success of Xinjiang Uygur Autonomous Region,China in poverty alleviation.Its Sustainable Development Goals(SDGs)are intertwined with the concerted economic and social development of Xinjiang and the objective of achieving shared prosperity within the region.This study established a sustainable development evaluation framework by selecting 15 SDGs and 20 secondary indicators from the United Nations’SDGs.The aim of this study is to quantitatively assess the progress of SDGs at the county(city)level on the northern slope of the Kunlun Mountains.The results indicate that there are substantial variations in the scores of SDGs among the nine counties and one city located on the northern slope of the Kunlun Mountains.Notable high scores of SDGs are observed in the central and eastern regions,whereas lower scores are prevalent in the western areas.The scores of SDGs,in descending order,are as follows:62.22 for Minfeng County,54.22 for Hotan City,50.21 for Qiemo County,42.54 for Moyu County,41.56 for Ruoqiang County,41.39 for Qira County,39.86 for Lop County,38.25 for Yutian County,38.10 for Pishan County,and 36.87 for Hotan County.The performances of SDGs reveal that Hotan City,Lop County,Minfeng County,and Ruoqiang County have significant sustainable development capacity because they have three or more SDGs ranked as green color.However,Hotan County,Moyu County,Qira County,and Yutian County show the poorest performance,as they lack SDGs with green color.It is important to establish and enhance mechanisms that can ensure sustained income growth among poverty alleviation beneficiaries,sustained improvement in the capacity of rural governance,and the gradual improvement of social security system.These measures will facilitate the effective implementation of SDGs.Finally,this study offers a valuable support for governmental authorities and relevant departments in their decision-making processes.In addition,these results hold significant reference value for assessing SDGs at the county(city)level,particularly in areas characterized by low levels of economic development. 展开更多
关键词 SUSTAINABLE Development goals(SDGs) Northern slope of the Kunlun Mountains Poverty alleviation Arid lands SUSTAINABLE development capacity
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APPLICATIONS OF HIGHER-ORDER UPWIND SCHEME FOR PROJECTILES IN TRANSONIC FLOW
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作者 鞠玉涛 郑亚 武晓松 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
针对弹丸跨音速粘性绕流流场进行了数值仿真研究,并与实验进行了对比。数值仿真的控制方程为雷诺平均的Navier-Stokes方程,湍流模型采用Baldwin-Lomax模型,应用了四阶的MUSCL TVD格式。结果表明,该方法可以取得高清晰度的流场结构。
关键词 TVD格式 NAVIER-STOKES方程 弹丸流动 APPLICATIONS OF higher-order UPWIND SCHEME FOR
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HIGHER-ORDER PETRI NET MODELS BASED ON ARTIFICIAL NEURAL NETWORKS
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作者 李金艳 陆以勤 +1 位作者 余英林 周伟诚 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 1997年第9期55-61,共7页
提出了一种新型Petri网———高阶Petri网,这种网可以应用于一阶谓词逻辑中的多项式子句集问题;还研究了目标转移结点T-不变量之间的关系,最后给出了几个例子。
关键词 高阶Petri网 可引发性 目标转移 多项式子句集 T-不变量
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Application of higher-order KdV-mKdV model with higher-degree nonlinear terms to gravity waves in atmosphere 被引量:6
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作者 李子良 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第10期4074-4082,共9页
Higher-order Korteweg-de Vries (KdV)-modified KdV (mKdV) equations with a higher-degree of nonlinear terms are derived from a simple incompressible non-hydrostatic Boussinesq equation set in atmosphere and are use... Higher-order Korteweg-de Vries (KdV)-modified KdV (mKdV) equations with a higher-degree of nonlinear terms are derived from a simple incompressible non-hydrostatic Boussinesq equation set in atmosphere and are used to investigate gravity waves in atmosphere. By taking advantage of the auxiliary nonlinear ordinary differential equation, periodic wave and solitary wave solutions of the fifth-order KdV-mKdV models with higher-degree nonlinear terms are obtained under some constraint conditions. The analysis shows that the propagation and the periodic structures of gravity waves depend on the properties of the slope of line of constant phase and atmospheric stability. The Jacobi elliptic function wave and solitary wave solutions with slowly varying amplitude are transformed into triangular waves with the abruptly varying amplitude and breaking gravity waves under the effect of atmospheric instability. 展开更多
关键词 gravity waves higher-order KdV-mKdV equation PROPAGATING BREAKING
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Mei symmetries and Mei conserved quantities for higher-order nonholonomic constraint systems 被引量:4
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作者 姜文安 李状君 罗绍凯 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第3期14-20,共7页
This paper presents the Mei symmetries and new types of non-Noether conserved quantities for a higher-order nonholonomic constraint mechanical system. On the basis of the form invariance of differential equations of m... This paper presents the Mei symmetries and new types of non-Noether conserved quantities for a higher-order nonholonomic constraint mechanical system. On the basis of the form invariance of differential equations of motion for dynamical functions under general infinitesimal transformation, the determining equations, the constraint restriction equations and the additional restriction equations of Mei symmetries of the system are constructed. The criterions of Mei symmetries, weak Mei symmetries and strong Mei symmetries of the system are given. New types of conserved quantities, i.e. the Mei symmetrical conserved quantities, the weak Mei symmetrical conserved quantities and the strong Mei symmetrical conserved quantities of a higher-order nonholonomic system, are obtained. Then, a deduction of the first-order nonholonomic system is discussed. Finally, two examples are given to illustrate the application of the method and then the results. 展开更多
关键词 higher-order nonholonomic system Mei symmetry Mei conserved quantity
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Influence of higher-order ionospheric delay correction on GPS precise orbit determination and precise positioning 被引量:5
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作者 Zhimin Liu Yangyang Li +1 位作者 Jinyun Guo Fei Li 《Geodesy and Geodynamics》 2016年第5期369-376,共8页
At present, Global Navigation Satellite Systems(GNSS) users usually eliminate the influence of ionospheric delay of the first order items by dual-frequency ionosphere-free combination. But there is still residual io... At present, Global Navigation Satellite Systems(GNSS) users usually eliminate the influence of ionospheric delay of the first order items by dual-frequency ionosphere-free combination. But there is still residual ionospheric delay error of higher order term. The influence of the higher-order ionospheric corrections on both GPS precision orbit determination and static Precise Point Positioning(PPP) are studied in this paper. The influence of higher-order corrections on GPS precision orbit determination, GPS observations and static PPP are analyzed by neglecting or considering the higher-order ionospheric corrections by using a globally distributed network which is composed of International GNSS Service(IGS) tracking stations. Numerical experimental results show that, the root mean square(RMS) in three dimensions of satellite orbit is 36.6 mme35.5 mm. The maximal second-order ionospheric correction is 9 cm, and the maximal third-order ionospheric correction is 1 cm. Higher-order corrections are influenced by latitude and station distribution. PPP is within 3 mm in the directions of east and up. Furthermore, the impact is mainly visible in the direction of north, showing a southward migration trend, especially at the lower latitudes where the influence value is likely to be bigger than 3 mm. 展开更多
关键词 higher-order ionosphere Precision orbit determination PPP Geomagnetic model
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兼顾能力与知识状态的Higher-Order CD-CAT选题方法
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作者 席崇钦 涂冬波 蔡艳 《江西师范大学学报(自然科学版)》 CAS 北大核心 2022年第2期111-117,共7页
Higher-order CD-CAT的选题方法是传统单目标(即只对知识状态自适应)选题方法,这将导致被试能力的测量精度不高.基于此,在高阶模型和PWKL选题方法的框架下,该文开发了适用于Higher-order CD-CAT的新选题方法,该方法在选题时能同时兼顾... Higher-order CD-CAT的选题方法是传统单目标(即只对知识状态自适应)选题方法,这将导致被试能力的测量精度不高.基于此,在高阶模型和PWKL选题方法的框架下,该文开发了适用于Higher-order CD-CAT的新选题方法,该方法在选题时能同时兼顾能力和知识状态.实验结果表明:与传统选题方法相比,新选题方法的能力和知识状态估计精度都更高,并且在题库安全性上也具有明显的优势. 展开更多
关键词 双目标CD-CAT 高阶模型 higher-order CD-CAT 选题方法
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A new higher-order shear deformation theory and refined beam element of composite laminates 被引量:3
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作者 WanjiChen ZhenWu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第1期65-69,共5页
A new higher-order shear deformation theory based on global-local superposition technique is developed. The theory satisfies the free surface conditions and the geometric and stress continuity conditions at interfaces... A new higher-order shear deformation theory based on global-local superposition technique is developed. The theory satisfies the free surface conditions and the geometric and stress continuity conditions at interfaces. The global displacement components are of the Reddy theory and local components are of the internal first to third-order terms in each layer. A two-node beam element based on this theory is proposed. The solutions are compared with 3D-elasticity solutions. Numerical results show that present beam element has higher computational efficiency and higher accuracy. 展开更多
关键词 Laminated composite beam higher-order shear deformation theory Refined beam element
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Tunneling dynamics of Bose-Einstein condensates with higher-order interactions in optical lattice 被引量:2
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作者 铁璐 薛具奎 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第12期95-100,共6页
The nonlinear Landau Zener tunneling and nonlinear Rabi oscillations of Bose-Einstein condensate (BEC) with higher-order atomic interaction between the Bloch bands in an accelerating optical lattice are discussed. W... The nonlinear Landau Zener tunneling and nonlinear Rabi oscillations of Bose-Einstein condensate (BEC) with higher-order atomic interaction between the Bloch bands in an accelerating optical lattice are discussed. Within the two-level model, the tunneling probability of BEC with higher-order atomic interaction between Bloch bands is obtained. We finds that the tunneling rate is closely related to the higher-order atomic interaction. Furthermore, the nonlinear Rabi oscillations of BEC with higher-order atomic interaction between the bands are discussed by imposing a periodic modulation on the level bias. Analytical expressions of the critical higher-order atomic interaction for suppressing/enhancing the Rabi oscillations are obtained. It is shown that the critical value strongly depends on the modulation parameters (i.e., the modulation amplitude and frequency) and the strength of periodic potential. 展开更多
关键词 Bose-Einstein condensates optical lattices higher-order interactions
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CONVERGENCE PROPERTIES OF HIGHER-ORDER MOMENT AND CUMULANT ESTIMATES 被引量:1
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作者 Li Hongwei(Institute of Information Science, Northern Jiaotong University, Beijing 100044)Cheng Qiansheng(School of Mathematical Sciences, Peking University, Beijing 100871) 《Journal of Electronics(China)》 1998年第3期240-247,共8页
The sample estimates of higher-order statistics are studied. Under certain conditions, the almost sure convergence of the third- and fourth-order moment and cumulant estimates of stationary processes is established. T... The sample estimates of higher-order statistics are studied. Under certain conditions, the almost sure convergence of the third- and fourth-order moment and cumulant estimates of stationary processes is established. The rate of almost sure convergence is obtained for the sample estimates of third- and fourth-order moment and cumulant. Additionally, it is shown that the third- and fourth-order moment and cumulant estimates are asymptotic normal. 展开更多
关键词 higher-order MOMENT higher-order CUMULANT ALMOST sure CONVERGENCE CONVERGENCE rate Asymptotic NORMALITY
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Experimental investigation on partially coherent higher-order non-diffractive beams 被引量:2
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作者 陈光明 华黎闽 +1 位作者 林惠川 蒲继雄 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期204-210,共7页
We experimentally study the generation of a partially coherent non-diffractive beam by focusing a partially coherent vortex beam with an axieon. The investigation results show that when the partially coherent vortex b... We experimentally study the generation of a partially coherent non-diffractive beam by focusing a partially coherent vortex beam with an axieon. The investigation results show that when the partially coherent vortex beam is focused by the axicon, the beam is transferred into a partially coherent higher-order non-diffractive beam. In the non-diffractive zone, the transverse intensity distribution of the partially coherent higher-order non-diffractive beam is invariant during propagation. In addition, the range of the non-diffractive zone is related to the coherence of the partially coherent vortex beam. The poorer the coherence of the partially coherent vortex beam, the shorter the range of the non-diffractive zone. 展开更多
关键词 physical optics higher-order non-diffractive Bessel beam AXICON partially coherence
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Numerical Simulation of Breaking Wave Based on Higher-Order Mild Slope Equation 被引量:2
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作者 陶建华 韩光 《China Ocean Engineering》 SCIE EI 2001年第2期269-280,共12页
The 'surface roller' to simulate wave energy dissipation of wave breaking is introduced into the random wave model based on approximate parabolic mild slope equation in this paper to simulate the random wave t... The 'surface roller' to simulate wave energy dissipation of wave breaking is introduced into the random wave model based on approximate parabolic mild slope equation in this paper to simulate the random wave transportation in chiding diffraction, refraction and breaking in nearshore areas. The roller breaking random wave higher-order approximate parabolic equation model has been verified by the existing experimental data for a plane slope beach and a circular shoal, and the numerical results of random wave breaking model agree with the experimental data very well, This model can be applied to calculate random wave propagation from deep to shallow water in large areas near the shore over natural topography. 展开更多
关键词 breaking wave ROLLER higher-order approximation parabolic mild slope equation random waves
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Estimate on the Dimension of Global Attractor for Nonlinear Higher-Order Coupled Kirchhoff Type Equations 被引量:3
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作者 Guoguang Lin Lingjuan Hu 《Advances in Pure Mathematics》 2018年第1期11-24,共14页
In this paper, we investigate the finite dimensions of the global attractor for nonlinear higher-order coupled Kirchhoff type equations with strong linear damping in Hilbert spaces E0?and E1. Under the appropriate ass... In this paper, we investigate the finite dimensions of the global attractor for nonlinear higher-order coupled Kirchhoff type equations with strong linear damping in Hilbert spaces E0?and E1. Under the appropriate assumptions, we acquire a precise estimate of the upper bound for its Hausdorff and Fractal dimensions. 展开更多
关键词 higher-order Kirchhoff-Type EQUATIONS Global Attractor Hausdorff DIMENSION Fractal DIMENSION
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Typical adaptive neural control for hypersonic vehicle based on higher-order filters 被引量:2
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作者 ZHAO Hewei LI Rui 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2020年第5期1031-1040,共10页
A typical adaptive neural control methodology is used for the rigid body model of the hypersonic vehicle. The rigid body model is divided into the altitude subsystem and the velocity subsystem. The proportional integr... A typical adaptive neural control methodology is used for the rigid body model of the hypersonic vehicle. The rigid body model is divided into the altitude subsystem and the velocity subsystem. The proportional integral differential(PID) controller is introduced to control the velocity track. The backstepping design is applied for constructing the controllers for the altitude subsystem.To avoid the explosion of differentiation from backstepping, the higher-order filter dynamic is used for replacing the virtual controller in the backstepping design steps. In the design procedure,the radial basis function(RBF) neural network is investigated to approximate the unknown nonlinear functions in the system dynamic of the hypersonic vehicle. The simulations show the effectiveness of the design method. 展开更多
关键词 hypersonic vehicle adaptive neural control higher-order filter differential explosion
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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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Mei symmetry and new conserved quantities of Tzénoff equations for higher-order nonholonomic system 被引量:3
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作者 ZHENG Shiwang ZHENG Wen 《商丘师范学院学报》 CAS 2012年第12期46-50,共5页
In this paper,the Mei symmetry of Tzénoff equations for the higher-order nonholonomic system and the new conserved quantities derived from that are researched,and the function expression of new conserved quantiti... In this paper,the Mei symmetry of Tzénoff equations for the higher-order nonholonomic system and the new conserved quantities derived from that are researched,and the function expression of new conserved quantities and criterion equation which deduces these conserved quantities are presented.This result establishes the theory basis for further researches on conservation laws of Tzénoff equations of the higher-order nonholonomic constraint system. 展开更多
关键词 higher-order nonholonomic constraint system Tzénoff equations Mei symmetry new conserved quantities
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