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Herglotz type Noether theorems of nonholonomic systems with generalized fractional derivatives
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作者 Yuan-Yuan Deng Yi Zhang 《Theoretical & Applied Mechanics Letters》 2025年第2期179-187,共9页
Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglo... Fractional calculus is widely used to deal with nonconservative dynamics because of its memorability and non-local properties.In this paper,the Herglotz principle with generalized operators is discussed,and the Herglotz type equations for nonholonomic systems are established.Then,the Noether symmetries are studied,and the conserved quantities are obtained.The results are extended to nonholonomic canonical systems,and the Herglotz type canonical equations and the Noether theorems are obtained.Two examples are provided to demonstrate the validity of the methods and results. 展开更多
关键词 Nonholonomic system Herglotz principle Noether theorem Generalized operators
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VANISHING THEOREMS OF THE BASIC P-HARMONIC FORMS ON COMPLETE FOLIATED RIEMANNIAN MANIFOLDS
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作者 NIE Yan-ci SHEN Zheng-han 《数学杂志》 2025年第3期195-204,共10页
In this paper,we study the basic p-harmonic forms on the complete foliated Riemannian manifolds.By using the method in[1],we show that if the basic mean curvature form is bounded and co-closed,and the transversal curv... In this paper,we study the basic p-harmonic forms on the complete foliated Riemannian manifolds.By using the method in[1],we show that if the basic mean curvature form is bounded and co-closed,and the transversal curvature operator is nonnegative and positive at least one point,then we obtain a vanishing theorem for L^(p)-integrably p-harmonic r-forms. 展开更多
关键词 basic p-harmonic form vanishing theorem foliated Riemannian manifold
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THEOREMS OF INTERVAL FUZZY SET AND ITS OPERATION RULES 被引量:3
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作者 吴顺祥 曹达 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第2期136-144,共9页
Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuz... Although the concept of interval fuzzy set and its properties have been defined, its three theorems and their effectiveness are not proved. Therefore, the knowledge presentation and its operation rules of interval fuzzy set are studied firstly, and then the cut set of interval fuzzy set is proposed. Moreover, the decomposition theo- rem, the representation theorem and the extension theorem of interval fuzzy set are presented. Finally, examples are given to demonstrate that the classical fuzzy set is a special case of interval fuzzy set and interval fuzzy set is an effective expansion of the classical fuzzy set. 展开更多
关键词 interval fuzzy set decomposition theorem representation theorem extension theorem
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Several Fundamental Theorems and Conservative Integrals in Quasicrystal Elasticity Theory 被引量:1
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作者 李显方 孙应飞 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期226-232,共7页
Aim To extend several fundamental theorems of conventional elasticity theory to quasicrystalelasticity theory. Methods The basic governing equations of quasicrystal elasticity theory and Gauss's theorem were appli... Aim To extend several fundamental theorems of conventional elasticity theory to quasicrystalelasticity theory. Methods The basic governing equations of quasicrystal elasticity theory and Gauss's theorem were applied in the derivation. Results and Conclusion The principle of virtual work, Betti's reciprocal theorem and the uniqueness theorem of quasicrystal elasticity theory are proud, and some conservative integrals in quasicrystal elasticty theory are obtained. 展开更多
关键词 quasicrystal elasticity theory conservative integral the principle ofvirtual work Betti's reciprocal theorem the uniqueness theorem
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On Some Fundamental Theorems in Stability Theory 被引量:27
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作者 徐道义 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期61-67,共7页
This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on ce... This paper gives several fundamental theorems for the stability, uniform stability, asymptotic stability and uniform asymptotic stability. Those theorems allow the derivative of Lyapunov functions to be positive on certain sets,relax the restriction about the rate of change of state variable in a system to be bounded in Marachkov's theorem and extend the related results in [4—7]. 展开更多
关键词 STABILITY Lyapunov fundamental theorem nonautonomous differential equations
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Primary Research on WSeveral Theorems,Laws and Corollaries of Hydrology 被引量:2
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作者 龚云 《Agricultural Science & Technology》 CAS 2009年第4期1-3,54,共4页
The conceptions of theorems, laws and corollaries of hydrology were put forward. Combining with hydrology practice, several theo- rems, laws as well as corollaries of hydrology were summarized. The study provided some... The conceptions of theorems, laws and corollaries of hydrology were put forward. Combining with hydrology practice, several theo- rems, laws as well as corollaries of hydrology were summarized. The study provided some references for accelerating the development of hydrology theory in these aspects and promoting the improvement of its production technology. 展开更多
关键词 HYDROLOGY THEOREM LAW Corollary
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McKean-Vlasov Backward Stochastic Differential Equations with Weak Monotonicity Coefficients
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作者 FU Zongkui FEI Dandan GUO Shanshan 《应用数学》 北大核心 2026年第1期98-107,共10页
This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic diff... This paper deals with Mckean-Vlasov backward stochastic differential equations with weak monotonicity coefficients.We first establish the existence and uniqueness of solutions to Mckean-Vlasov backward stochastic differential equations.Then we obtain a comparison theorem in one-dimensional situation. 展开更多
关键词 McKean-Vlasov backward stochastic differential equation Weak monotonicity condition Comparison theorem
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On the Comparison Theorems for the Volume of Tubes in Kahlerian Manifolds
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作者 陈维桓 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第2期91-100,共10页
In this note we give some comparison theorems for the volume of tubes around a complex submanifold in a Kahlerian monifold.
关键词 Kahlerian manifold TUBE VOLUME comparison theorem
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KKM TYPE THEOREMS AND COINCIDENCE THEOREMS ON L-CONVEX SPACES 被引量:13
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作者 丁协平 《Acta Mathematica Scientia》 SCIE CSCD 2002年第3期419-426,共8页
Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixe... Some KKM theorems and coincidence theorems involving admissible set-valued mappings and the set-valued mappings with compactly local intersection property are proved in L-convex: spaces. As applications, some new fixed point theorems are obtained in L-convex spaces. These theorems improve and generalize many important known results in recent literature. 展开更多
关键词 KKM type theorem coincidence theorem L-convex space
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VECTORIAL EKELAND'S VARIATIONAL PRINCIPLE WITH A W-DISTANCE AND ITS EQUIVALENT THEOREMS 被引量:8
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作者 丘京辉 李博 贺飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2221-2236,共16页
By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variatio... By using the properties of w-distances and Gerstewitz's functions, we first give a vectorial Takahashi's nonconvex minimization theorem with a w-distance. From this, we deduce a general vectorial Ekeland's variational principle, where the objective function is from a complete metric space into a pre-ordered topological vector space and the perturbation contains a w-distance and a non-decreasing function of the objective function value. From the general vectorial variational principle, we deduce a vectorial Caristfs fixed point theorem with a w-distance. Finally we show that the above three theorems are equivalent to each other. The related known results are generalized and improved. In particular, some conditions in the theorems of [Y. Araya, Ekeland's variational principle and its equivalent theorems in vector optimization, J. Math. Anal. Appl. 346(2008), 9-16] are weakened or even completely relieved. 展开更多
关键词 Takahashi's minimization theorem Ekeland's variational principle Caristi'sfixed point theorem Gerstewitz's function w-distance
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Noether's theorems of a fractional Birkhoffian system within Riemann-Liouville derivatives 被引量:17
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作者 周燕 张毅 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第12期281-288,共8页
The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding ... The Noether symmetry and the conserved quantity of a fractional Birkhoffian system are studied within the Riemann–Liouville fractional derivatives. Firstly, the fractional Birkhoff's equations and the corresponding transversality conditions are given. Secondly, from special to general forms, Noether's theorems of a standard Birhoffian system are given, which provide an approach and theoretical basis for the further research on the Noether symmetry of the fractional Birkhoffian system. Thirdly, the invariances of the fractional Pfaffian action under a special one-parameter group of infinitesimal transformations without transforming the time and a general one-parameter group of infinitesimal transformations with transforming the time are studied, respectively, and the corresponding Noether's theorems are established. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 fractional Birkhoffian system Noether's theorem fractional conserved quantity Riemann–Liouville fractional derivative
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CENTRAL LIMIT THEOREMS FOR A BRANCHING RANDOM WALK WITH A RANDOM ENVIRONMENT IN TIME 被引量:7
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作者 高志强 刘全升 汪和松 《Acta Mathematica Scientia》 SCIE CSCD 2014年第2期501-512,共12页
We consider a branching random walk with a random environment m time, in which the offspring distribution of a particle of generation n and the distribution of the displacements of its children depend on an environmen... We consider a branching random walk with a random environment m time, in which the offspring distribution of a particle of generation n and the distribution of the displacements of its children depend on an environment indexed by the time n. The envi- ronment is supposed to be independent and identically distributed. For A C R, let Zn(A) be the number of particles of generation n located in A. We show central limit theorems for the counting measure Zn (-) with appropriate normalization. 展开更多
关键词 Branching random walk random environment in time central limit theorems
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NONSMOOTH CRITICAL POINT THEOREMS AND ITS APPLICATIONS TO QUASILINEAR SCHRDINGER EQUATIONS 被引量:5
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作者 李周欣 沈尧天 《Acta Mathematica Scientia》 SCIE CSCD 2016年第1期73-86,共14页
In this paper, the existence and nonexistence of solutions to a class of quasilinear elliptic equations with nonsmooth functionals are discussed, and the results obtained are applied to quasilinear SchrSdinger equatio... In this paper, the existence and nonexistence of solutions to a class of quasilinear elliptic equations with nonsmooth functionals are discussed, and the results obtained are applied to quasilinear SchrSdinger equations with negative parameter which arose from the study of self-channeling of high-power ultrashort laser in matter. 展开更多
关键词 nonsmooth critical point theorems quasilinear elliptic equations SchrSdingerequation
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EXISTENCE THEOREMS FOR A SECOND ORDER THREE-POINT BOUNDARY VALUE PROBLEM WITH IMPULSES 被引量:5
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作者 SunYing ZhuDeming 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2005年第2期165-174,共10页
In this paper,two existence theorems are given concerning the following 3-point boundary value problem of second order differential systems with impulses[HL(2:1,1Z;2,1Z]x″(t)=f(t,x(t),x′(t)),t∈(0,1),t≠t_k,k=1,2,..... In this paper,two existence theorems are given concerning the following 3-point boundary value problem of second order differential systems with impulses[HL(2:1,1Z;2,1Z]x″(t)=f(t,x(t),x′(t)),t∈(0,1),t≠t_k,k=1,2,...,m, Δx|_~t=t_k =I_k(x(t_k)),k=1,2,...,m, Δx′|_~t=t_k =J_k(x(t_k),x′(t_k)),k=1,2,...,m, x(0)=0,x(1)=αx(η). 展开更多
关键词 point boundary value problem IMPULSE Leray-Schauder theorem.
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DISTORTION THEOREMS FOR SUBCLASSES OF STARLIKE MAPPINGS ALONG A UNIT DIRECTION IN C^n 被引量:4
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作者 卢金 刘太顺 王建飞 《Acta Mathematica Scientia》 SCIE CSCD 2012年第4期1675-1680,共6页
In this paper, we obtain a distortion theorem of Jacobian matrix for biholomorphic subclasses of starlike mappings along a unit direction on the unit polydisc. These results extend the classical distortion theorem of ... In this paper, we obtain a distortion theorem of Jacobian matrix for biholomorphic subclasses of starlike mappings along a unit direction on the unit polydisc. These results extend the classical distortion theorem of starlike mappings to higher dimensions. We then give an upper bound estimate for biholomorphic subclasses of starlike mappings along a unit direction in a complex Banach space. 展开更多
关键词 subclasses of starlike mappings distortion theorem Banach space growththeorem
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Attribute Disturbance of Knowledge and Attribute Disturbance Theorems 被引量:3
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作者 ZHANG Guan-yu DU Ying-ling 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第4期574-581,共8页
By using the dynamic characteristic of one direction S-rough sets(one direction singular rough sets) and dual of one direction S-rough sets(dual of one direction singular rough sets), the concepts of attribute dis... By using the dynamic characteristic of one direction S-rough sets(one direction singular rough sets) and dual of one direction S-rough sets(dual of one direction singular rough sets), the concepts of attribute disturbance of knowledge, the attribute disturbance degree of knowledge, and the disturbance coefficient of knowledge are given. By employing these concepts, the cardinal order theorem of the attribute disturbance knowledge, the unit circle theorem of the attribute disturbance knowledge, and the discernible theorem of the attribute disturbance knowledge are presented. 展开更多
关键词 KNOWLEDGE attribute disturbance cardinal order theorem unit circle theorem knowledge discernment
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Integrating Factors and Conservation Theorems of Nonholonomic Dynamical System of Relative Motion 被引量:3
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作者 QIAO Yong-Fen ZHAO Shu-Hong LI Ren-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期217-220,共4页
The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integ... The integrating factors and conservation theorems of nonholonomic dynamical system of relative motion are studied. First, the dynamical equations of relative motion of system are written. Next, the definition of integrating factors is given, and the necessary conditions for the existence of the conserved quantities are studied in detail. Then, the conservation theorem and its inverse of system are established. Finally, an example is given to illustrate the application of the result. 展开更多
关键词 nonholonomic system relative motion integrating factor conservation theorem
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Integrating factors and conservation theorems of constrained Birkhoffian systems 被引量:3
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作者 乔永芬 赵淑红 李仁杰 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2777-2781,共5页
In this paper the conservation theorems of the constrained Birkhoffian systems are studied by using the method of integrating factors. The differential equations of motion of the system are written. The definition of ... In this paper the conservation theorems of the constrained Birkhoffian systems are studied by using the method of integrating factors. The differential equations of motion of the system are written. The definition of integrating factors is given for the system. The necessary conditions for the existence of the conserved quantity for the system are studied. The conservation theorem and its inverse for the system are established. Finally, an example is given to illustrate the application of the results. 展开更多
关键词 integration factor conservation theorem constrained Birkhoffian system
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A Laurent Expansion and Residue Theorems of k-Regular Functions in Clifford Analysis 被引量:2
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作者 KU Min DU Jinyuan 《Wuhan University Journal of Natural Sciences》 CAS 2009年第2期97-102,共6页
In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness... In this context, we mainly study the behavior in the neighborhood of finite singular points for k-regular functions in R1^n with values in R0、n. We get a Laurent expansion of them in an open set, prove its uniqueness, give the definitions of k-poles, isolated and essential singular points and removable singularity, discuss some properties, and further obtain the residue theorems. 展开更多
关键词 Clifford algebra k-regular functions Laurent expansion residue theorems SINGULARITY
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WEAK ORLICZ SPACE AND ITS CONVERGENCE THEOREMS 被引量:3
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作者 刘宁 叶永刚 《Acta Mathematica Scientia》 SCIE CSCD 2010年第5期1492-1500,共9页
In this article, a class of weak Orlicz function spaces is defined and their basic properties are discused. In particular, for the sequences in weak Orlicz space, we establish several basic convergence theorems includ... In this article, a class of weak Orlicz function spaces is defined and their basic properties are discused. In particular, for the sequences in weak Orlicz space, we establish several basic convergence theorems including bounded convergence theorem, control convergence theorem and Vitali-type convergence theorem and so on. Moreover, the conditional compactness of its subsets is also discussed. 展开更多
关键词 weak Orlicz space convergence theorem conditional compactness
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