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Accounting for Quadratic and Cubic Invariants in Continuum Mechanics–An Overview
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作者 Artur V.Dmitrenko Vladislav M.Ovsyannikov 《Fluid Dynamics & Materials Processing》 EI 2024年第9期1925-1939,共15页
The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first ... The differential equations of continuum mechanics are the basis of an uncountable variety of phenomena and technological processes in fluid-dynamics and related fields.These equations contain derivatives of the first order with respect to time.The derivation of the equations of continuum mechanics uses the limit transitions of the tendency of the volume increment and the time increment to zero.Derivatives are used to derive the wave equation.The differential wave equation is second order in time.Therefore,increments of volume and increments of time in continuum mechanics should be considered as small but finite quantities for problems of wave formation.This is important for calculating the generation of sound waves and water hammer waves.Therefore,the Euler continuity equation with finite time increments is of interest.The finiteness of the time increment makes it possible to take into account the quadratic and cubic invariants of the strain rate tensor.This is a new branch in hydrodynamics.Quadratic and cubic invariants will be used in differential wave equations of the second and third order in time. 展开更多
关键词 Quadratic invariant cubic invariant continuity equation generation of periodic waves N.E.Zhukovsky’s hydraulic shock TURBULENCE
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Constructing Hopf Insulator from Geometric Perspective of Hopf Invariant
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作者 常治文 郝维昌 +1 位作者 Miguel Bustamante 刘鑫 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第3期121-126,共6页
We propose a method to construct Hopf insulators based on the study of topological defects from the geometric perspective of Hopf invariant I.Firstly,we prove two types of topological defects naturally inhering in the... We propose a method to construct Hopf insulators based on the study of topological defects from the geometric perspective of Hopf invariant I.Firstly,we prove two types of topological defects naturally inhering in the inner differential structure of the Hopf mapping.One type is the four-dimensional point defects. 展开更多
关键词 HOPF TOPOLOGICAL invariant
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Solving Invariant Problem of Cauchy Means Based on Wronskian Determinant
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作者 Yingjun Ni Fen Wang 《Advances in Pure Mathematics》 2024年第7期515-522,共8页
This paper studied the invariance of the Cauchy mean with respect to the arithmetic mean when the denominator functions satisfy certain conditions. The partial derivatives of Cauchy’s mean on the diagonal are obtaine... This paper studied the invariance of the Cauchy mean with respect to the arithmetic mean when the denominator functions satisfy certain conditions. The partial derivatives of Cauchy’s mean on the diagonal are obtained by using the method of Wronskian determinant in the process of solving. Then the invariant equation is solved by using the obtained partial derivatives. Finally, the solutions of invariant equations when the denominator functions satisfy the same simple harmonic oscillator equation or the denominator functions are power functions that have been obtained. 展开更多
关键词 Cauchy Mean Wronskian Determinant Arithmetic Mean invariant Equation
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Optimized Evaluation of Mobile Base Station by Modern Topological Invariants
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作者 Khalid Hamid Muhammad Waseem Iqbal +3 位作者 Muhammad Usman Ashraf Ahmed Mohammed Alghamdi Adel A.Bahaddad Khalid Ali Almarhabi 《Computers, Materials & Continua》 SCIE EI 2023年第1期363-378,共16页
Due to a tremendous increase in mobile traffic,mobile operators have started to restructure their networks to offload their traffic.Newresearch directions will lead to fundamental changes in the design of future Fifth... Due to a tremendous increase in mobile traffic,mobile operators have started to restructure their networks to offload their traffic.Newresearch directions will lead to fundamental changes in the design of future Fifthgeneration(5G)cellular networks.For the formal reason,the study solves the physical network of the mobile base station for the prediction of the best characteristics to develop an enhanced network with the help of graph theory.Any number that can be uniquely calculated by a graph is known as a graph invariant.During the last two decades,innumerable numerical graph invariants have been portrayed and used for correlation analysis.In any case,no efficient assessment has been embraced to choose,how much these invariants are connected with a network graph.This paper will talk about two unique variations of the hexagonal graph with great capability of forecasting in the field of optimized mobile base station topology in setting with physical networks.Since K-banhatti sombor invariants(KBSO)and Contrharmonic-quadratic invariants(CQIs)are newly introduced and have various expectation characteristics for various variations of hexagonal graphs or networks.As the hexagonal networks are used in mobile base stations in layered,forms called honeycomb.The review settled the topology of a hexagon of two distinct sorts with two invariants KBSO and CQIs and their reduced forms.The deduced outcomes can be utilized for the modeling of mobile cellular networks,multiprocessors interconnections,microchips,chemical compound synthesis and memory interconnection networks.The results find sharp upper bounds and lower bounds of the honeycomb network to utilize the Mobile base station network(MBSN)for the high load of traffic and minimal traffic also. 展开更多
关键词 Hexagonal networks k-banhatti sombor invariants MAPLE network graph artificial intelligence contraharmonic-quadratic invariants HONEYCOMB
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On the Construction and Classification of the Common Invariant Solutions for Some P(1,4) -Invariant Partial Differential Equations
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作者 Vasyl M. Fedorchuk Volodymyr I. Fedorchuk 《Applied Mathematics》 2023年第11期728-747,共20页
We consider the following (1 + 3)-dimensional P(1,4)-invariant partial differential equations (PDEs): the Eikonal equation, the Euler-Lagrange-Born-Infeld equation, the homogeneous Monge-Ampère equation, the inho... We consider the following (1 + 3)-dimensional P(1,4)-invariant partial differential equations (PDEs): the Eikonal equation, the Euler-Lagrange-Born-Infeld equation, the homogeneous Monge-Ampère equation, the inhomogeneous Monge-Ampère equation. The purpose of this paper is to construct and classify the common invariant solutions for those equations. For this aim, we have used the results concerning construction and classification of invariant solutions for the (1 + 3)-dimensional P(1,4)-invariant Eikonal equation, since this equation is the simplest among the equations under investigation. The direct checked allowed us to conclude that the majority of invariant solutions of the (1 + 3)-dimensional Eikonal equation, obtained on the base of low-dimensional (dimL ≤ 3) nonconjugate subalgebras of the Lie algebra of the Poincaré group P(1,4), satisfy all the equations under investigation. In this paper, we present obtained common invariant solutions of the equations under study as well as the classification of those invariant solutions. 展开更多
关键词 Symmetry Reduction Classification of invariant Solutions Common invariant Solutions The Eikonal Equations The Euler-Lagrange-Born-Infeld Equations The Monge-Ampère Equations Classification of Lie Algebras Nonconjugate Subalgebras Poincaré Group P(1 4)
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Invariant measures for the strong-facilitated exclusion process
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作者 LEI Yu-huan SU Zhong-gen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2023年第3期317-337,共21页
Consider a generalized model of the facilitated exclusion process, which is a onedimensional exclusion process with a dynamical constraint that prevents the particle at site x from jumping to x+1 (or x-1) if the sites... Consider a generalized model of the facilitated exclusion process, which is a onedimensional exclusion process with a dynamical constraint that prevents the particle at site x from jumping to x+1 (or x-1) if the sites x-1, x-2 (or x+1, x+2) are empty. It is nongradient and lacks invariant measures of product form. The purpose of this paper is to identify the invariant measures and to show that they satisfy both exponential decay of correlations and equivalence of ensembles. These properties will play a pivotal role in deriving the hydrodynamic limit. 展开更多
关键词 equivalence of ensembles exclusion process facilitated dynamic invariant measure
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Invariant manifold growth formula in cylindrical coordinates and its application for magnetically confined fusion
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作者 魏文崟 梁云峰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2023年第9期51-67,共17页
For three-dimensional vector fields,the governing formula of invariant manifolds grown from a hyperbolic cycle is given in cylindrical coordinates.The initial growth directions depend on the Jacobians of Poincaré... For three-dimensional vector fields,the governing formula of invariant manifolds grown from a hyperbolic cycle is given in cylindrical coordinates.The initial growth directions depend on the Jacobians of Poincarémap on that cycle,for which an evolution formula is deduced to reveal the relationship among Jacobians of different Poincarésections.The evolution formula also applies to cycles in arbitrary finite n-dimensional autonomous continuous-time dynamical systems.Non-Möbiusian/Möbiusian saddle cycles and a dummy X-cycle are constructed analytically as demonstration.A real-world numeric example of analyzing a magnetic field timeslice on EAST is presented. 展开更多
关键词 magnetic topology TOKAMAK invariant manifold
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Second-Order Invariant Domain Preserving ALE Approximation of Euler Equations
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作者 Jean-Luc Guermond Bojan Popov Laura Saavedra 《Communications on Applied Mathematics and Computation》 2023年第2期923-945,共23页
An invariant domain preserving arbitrary Lagrangian-Eulerian method for solving non-linear hyperbolic systems is developed.The numerical scheme is explicit in time and the approximation in space is done with continuou... An invariant domain preserving arbitrary Lagrangian-Eulerian method for solving non-linear hyperbolic systems is developed.The numerical scheme is explicit in time and the approximation in space is done with continuous finite elements.The method is made invar-iant domain preserving for the Euler equations using convex limiting and is tested on vari-ous benchmarks. 展开更多
关键词 Conservation equations Hyperbolic systems Arbitrary Lagrangian-Eulerian Moving meshes invariant domains High-order method Convex limiting Finite element method
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Lie symmetry analysis and invariant solutions for the(3+1)-dimensional Virasoro integrable model
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作者 胡恒春 李雅琦 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期249-254,共6页
Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with a... Lie symmetry analysis is applied to a(3+1)-dimensional Virasoro integrable model and the corresponding similarity reduction equations are obtained with the different infinitesimal generators.Invariant solutions with arbitrary functions for the(3+1)-dimensional Virasoro integrable model,including the interaction solution between a kink and a soliton,the lump-type solution and periodic solutions,have been studied analytically and graphically. 展开更多
关键词 (3+1)-dimensional Virasoro integrable model Lie symmetry invariant solutions
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A road map to higher genus Gromov-Witten invariants of Calabi-Yau quintics
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作者 CHANG Huailiang LI Weiping 《中山大学学报(自然科学版)(中英文)》 CAS CSCD 北大核心 2023年第2期1-9,共9页
This is a survey of using NMSP method to study higher genus Gromov-Witten invariants of Calabi-Yau quintics.It emphasizes on how and why the various methods are introduced to solve several important conjectures for hi... This is a survey of using NMSP method to study higher genus Gromov-Witten invariants of Calabi-Yau quintics.It emphasizes on how and why the various methods are introduced to solve several important conjectures for higher genus Gromov-Witten invariants of Calabi-Yau quintics. 展开更多
关键词 Gromov-Witten invariants Calabi-Yau manifolds
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Mathematical Aspects of SU (2) and SO(3,R) Derived from Two-Mode Realization in Coordinate-Invariant Form
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作者 Alfred Wünsche 《Journal of Modern Physics》 CAS 2023年第3期361-413,共53页
Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter  instead of the Euler angles and ... Some mathematical aspects of the Lie groups SU (2) and in realization by two pairs of boson annihilation and creation operators and in the parametrization by the vector parameter  instead of the Euler angles and the vector parameter c of Fyodorov are developed. The one-dimensional root scheme of SU (2) is embedded in two-dimensional root schemes of some higher Lie groups, in particular, in inhomogeneous Lie groups and is represented in text and figures. The two-dimensional fundamental representation of SU (2) is calculated and from it the composition law for the product of two transformations and the most important decompositions of general transformations in special ones are derived. Then the transition from representation of SU (2) to of is made where in addition to the parametrization by vector  the convenient parametrization by vector c is considered and the connections are established. The measures for invariant integration are derived for and for SU (2) . The relations between 3D-rotations of a unit sphere to fractional linear transformations of a plane by stereographic projection are discussed. All derivations and representations are tried to make in coordinate-invariant way. 展开更多
关键词 Boson Operators Lie Algebra Root Diagram invariant Integration Hamilton-Cayley Identity Cayley-Gibbs-Fyodorov Parametrization Composition Law Quaternion Stereographic Projection Fractional Linear Transformation
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Lie symmetries, perturbation to symmetries and adiabatic invariants of Poincaré equations 被引量:10
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作者 陈向炜 刘翠梅 李彦敏 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第3期470-474,共5页
Based on the invariance of differential equations under infinitesimal transformations, Lie symmetry, laws of conservations, perturbation to the symmetries and adiabatic invariants of Poincaré equations are presen... Based on the invariance of differential equations under infinitesimal transformations, Lie symmetry, laws of conservations, perturbation to the symmetries and adiabatic invariants of Poincaré equations are presented. The concepts of Lie symmetry and higher order adiabatic invariants of Poincaré equations are proposed. The conditions for existence of the exact invariants and adiabatic invariants are proved, and their forms are also given. In addition, an example is presented to illustrate these results. 展开更多
关键词 Poincaré equations perturbation to symmetry exact invariant adiabatic invariant
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Lie symmetrical perturbation and adiabatic invariants of generalized Hojman type for Lagrange systems 被引量:7
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作者 罗绍凯 陈向炜 郭永新 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第11期3176-3181,共6页
Based on the invariance of differential equations under infinitesimal transformations of group, Lie symmetries, exact invariants, perturbation to the symmetries and adiabatic invariants in form of non-Noether for a La... Based on the invariance of differential equations under infinitesimal transformations of group, Lie symmetries, exact invariants, perturbation to the symmetries and adiabatic invariants in form of non-Noether for a Lagrange system are presented. Firstly, the exact invariants of generalized Hojman type led directly by Lie symmetries for a Lagrange system without perturbations are given. Then, on the basis of the concepts of Lie symmetries and higher order adiabatic invariants of a mechanical system, the perturbation of Lie symmetries for the system with the action of small disturbance is investigated, the adiabatic invariants of generalized Hojman type for the system are directly obtained, the conditions for existence of the adiabatic invariants and their forms are proved. Finally an example is presented to illustrate these results. 展开更多
关键词 Lagrange system Lie symmetrical perturbation exact invariant adiabatic invariant of generalized Hojman type
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Exact invariants and adiabatic invariants of Raitzin's canonical equations of motion for a nonlinear nonholonomic mechanical system 被引量:6
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作者 乔永芬 李仁杰 孙丹姗 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期1919-1925,共7页
The exact invariants and the adiabatic invariants of Raitzin's canonical equations of motion for a nonlinear nonholonomic mechanical system are studied. The relations between the invariants and the symmetries of the ... The exact invariants and the adiabatic invariants of Raitzin's canonical equations of motion for a nonlinear nonholonomic mechanical system are studied. The relations between the invariants and the symmetries of the system are established. Based on the concept of higher-order adiabatic invariant of a mechanical system under the action of a small perturbation, the forms of the exact invariants and adiabatic invariants and the conditions for their existence are proved. Finally, the inverse problem of the perturbation to symmetries of the system is studied and an example is also given to illustrate the application of the results. 展开更多
关键词 nonholonomic system Raitzin's canonical equation SYMMETRY PERTURBATION exactinvariant adiabatic invariant
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Hojman Exact Invariants and Adiabatic Invariants of Hamilton System 被引量:1
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作者 WANG Peng FANG Jian-Hui DING Ning ZHANG Xiao-Ni College of Physics Science and Technology,China University of Petroleum,Dongying 257061,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第12期996-998,共3页
The perturbation to Lie symmetry and adiabatic invariants are studied.Based on the concept of higher-order adiabatic invariants of mechanical systems with action of a small perturbation,the perturbation to Lie symmetr... The perturbation to Lie symmetry and adiabatic invariants are studied.Based on the concept of higher-order adiabatic invariants of mechanical systems with action of a small perturbation,the perturbation to Lie symmetryis studied,and Hojman adiabatic invariants of Hamilton system are obtained.An example is given to illustrate theapplication of the results. 展开更多
关键词 Hamilton system SYMMETRY exact invariant adiabatic invariant
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INVARIANT FORM AND INTEGRAL INVARIANTS ON KAHLER MANIFOLD
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作者 张荣业 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第2期269-278,共10页
The important notions and results of the integral invariants of Poincard and Cartan-Poincard and the relationship between integral invariant and invariant form established first by E. Cartan in the classical mechanics... The important notions and results of the integral invariants of Poincard and Cartan-Poincard and the relationship between integral invariant and invariant form established first by E. Cartan in the classical mechanics are generalized to Hamilton mechanics on Kiihler manifold, by the theory of modern geometry and advanced calculus, to get the corresponding wider arid deeper results. differential 展开更多
关键词 Kahler manifold symplectic manifold invariant form integral invariant vector field form field Lie derivative exterior differential
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PERSISTENCE OF RESONANT INVARIANT TORI WITH NON-HAMILTONIAN PERTURBATION
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作者 白玉真 朱德明 《Acta Mathematica Scientia》 SCIE CSCD 2005年第3期481-491,共11页
A persistence theorem for resonant invariant tori with non-Hamiltonian perturbation is proved. The method is a combination of the theory of normally hyperbolic invariant manifolds and an appropriate continuation metho... A persistence theorem for resonant invariant tori with non-Hamiltonian perturbation is proved. The method is a combination of the theory of normally hyperbolic invariant manifolds and an appropriate continuation method. The results obtained are extensions of Chicone’s for the three dimensional non-Hamiltonian systems. 展开更多
关键词 Normally hyperbolic invariant manifolds invariant tori PERSISTENCE continuation method
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Classification of Four-Qubit States by Means of a Stochastic Local Operation and the Classical Communication Invariant
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作者 查新未 马刚龙 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第2期24-27,共4页
It is a recent observation that entanglement classification for qubits is closely related to stochastic local operations and classical communication(SLOCC)invariants.Verstraete et al.[Phys.Rev.A 65(2002)052112]showed ... It is a recent observation that entanglement classification for qubits is closely related to stochastic local operations and classical communication(SLOCC)invariants.Verstraete et al.[Phys.Rev.A 65(2002)052112]showed that for pure states of four qubits there are nine different degenerate SLOCC entanglement classes.Li et al.[Phys.Rev.A 76(2007)052311]showed that there are at least 28 distinct true SLOCC entanglement classes for four qubits by means of the SLOCC invariant and semi-invariant.We give 16 different entanglement classes for four qubits by means of basic SLOCC invariants. 展开更多
关键词 invariantS invariant operations
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OHTSUKI’S INVARIANT CANNOT DETERMINE THE FULL SO(3) QUANTUM INVARIANTS
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作者 李邦河 李天军 《Acta Mathematica Scientia》 SCIE CSCD 2009年第3期642-644,共3页
Two lens spaces are given to show, that Ohtsuki’sτ for rational homology spheres does not determine Kirby-Melvin’s {τ r′, r odd ≥ 3}.
关键词 Ohtsuki's invariant SO(3) quantum invariants lens space
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Joint Invariants and Joint Differential Invariants of Some Transformation Groups
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作者 BAI Yong-qiang LIU Zhen PEI Ming 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期337-343,共7页
The theory of moving frames developed by Peter J Olver and M Fels has impor-tant applications to geometry, classical invariant theory. We will use this theory to classify joint invariants and joint differential invari... The theory of moving frames developed by Peter J Olver and M Fels has impor-tant applications to geometry, classical invariant theory. We will use this theory to classify joint invariants and joint differential invariants of some transformation groups. 展开更多
关键词 moving frames joint invariants joint differential invariants
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