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Herglotz type Noether theorems of nonholonomic systems with generalized fractional derivatives 被引量:1
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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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Infinitely Many Negative Energy Solutions for Sublinear Schr¨odinger-Poisson System
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作者 CHENG Rong WU Xiao 《应用数学》 北大核心 2026年第2期564-572,共9页
In this paper,we consider a Schr¨odinger-Poisson system with sublinear nonlinearity.The growth of nonlinearity depends on potential function and a bounded function.We first obtain the existence of nontrivial solu... In this paper,we consider a Schr¨odinger-Poisson system with sublinear nonlinearity.The growth of nonlinearity depends on potential function and a bounded function.We first obtain the existence of nontrivial solution sequence with negative energy for the system via a variant Clark’s theorem.Then we get the asymptotical property of the solution sequence by L∞norm. 展开更多
关键词 Variational method Schr¨odinger-Poisson system Multiple solutions Clark’s theorem ITERATION
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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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The Noncommutative Residue and Sub-Riemannian Limits for the Twisted BCV Spaces
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作者 LI Hong-feng LIU Ke-feng WANG Yong 《Chinese Quarterly Journal of Mathematics》 2026年第1期15-37,共23页
In this paper,we derive the sub-Riemannian version of the Kastler-Kalau-Walze type theorem and the Dabrowski-Sitarz-Zalecki type theorem for the twisted BCV spaces.We also compute the Connes conformal invariants for t... In this paper,we derive the sub-Riemannian version of the Kastler-Kalau-Walze type theorem and the Dabrowski-Sitarz-Zalecki type theorem for the twisted BCV spaces.We also compute the Connes conformal invariants for the twisted product,as well as the sub-Riemannian limits of the Connes conformal invariants for the twisted BCV spaces. 展开更多
关键词 Scalar curvature Sub-Riemannian limit Conformal invarints Twisted BCV spaces Kastler-Kalau-Walze type theorems Dabrowski-Sitarz-Zalecki type theorems
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任意三角形的射影定理的探究及应用
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作者 陶永芹 《中学生数理化(高一数学)》 2026年第3期21-21,共1页
任意三角形的射影定理:在任意ABC中,设a,b,c分别为△ABC的内角A,B,C的对边,则a=bcosC+ccosB,b=ccosA acosC,c=acosB+bcosA。
关键词 triangle projection theorem TRIGONOMETRY Pythagorean theorem
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Periodic solutions and fixed-time synchronization of discontinuous time-varying delayed Cohen-Grossberg neural networks
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作者 ZHANG Yi-cheng KONG Fan-chao Rathinasamy Sakthivel 《Applied Mathematics(A Journal of Chinese Universities)》 2026年第1期140-160,共21页
In this paper,a class of discontinuous Cohen-Grossberg neural networks with timevarying delays is considered.Firstly,under the extended Filippov differential inclusions framework,the problem of periodic solutions of t... In this paper,a class of discontinuous Cohen-Grossberg neural networks with timevarying delays is considered.Firstly,under the extended Filippov differential inclusions framework,the problem of periodic solutions of the considered neural networks with more relaxed conditions imposed on the amplification functions is analyzed by using set-valued mapping and Kakutani's fixed point theorem,which has rarely been used to study such problem.Secondly,the fixed-time synchronization of the error system of the considered neural networks is also investigated by designing a novel control strategy,which can improve not only the previous ones with sign function greatly,but also can reduce the chattering phenomenon.Finally,two numerical examples are presented to further illustrate the validity of the obtained results. 展开更多
关键词 Cohen-Grossberg neural networks periodic solutions Kakutani's fixed point theorem differential inclusions theory fixed-time synchronization
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A GATED SERVICE SINGLE VACATION M/G/1 QUEUE SYSTEM WITH SETUP AND CLOSEDOWN TIMES AND DIFFERENT CUSTOMER ARRIVAL RATES
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作者 Ying SUN Zhanyou MA Tongyu XU 《Acta Mathematica Scientia》 2026年第1期407-426,共20页
A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who... A gated service single vacation M/G/1 queue with setup and closedown periods,and different customer arrival rates,is studied in this paper.The probability generating function of the number of systems for customers who are at the initial moment of service period is analyzed by using a total probability theorem,and the stability condition of the system is obtained.The stationary distribution of the queue length is solved by the regeneration cycle method.The stochastic decomposition of queue length in the steady state is calculated,and the service cycle is obtained.Moreover,classified discussions are established in order to solve the steady-state distribution for the waiting time.The variation of system performance indicators with parameters is analyzed by performing numerical experiments. 展开更多
关键词 different arrival rates regeneration cycle method stochastic decomposition theorem stationary queue length
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Repetitive Control:Basic Concept,Fundamental Theory,and Practical Applications
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作者 Jinhua She Shinji Hara +2 位作者 Qing-Long Han Lan Zhou Min Wu 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期243-258,共16页
As a closed-loop learning control method,repetitive control has been widely used in a variety of areas from appliances to aviation.A repetitive control system features perfect reference tracking and disturbance reject... As a closed-loop learning control method,repetitive control has been widely used in a variety of areas from appliances to aviation.A repetitive control system features perfect reference tracking and disturbance rejection in the steady state for periodic signals with a fixed period.This characteristic is important not only for conventional technologies and conventional industries but also for advanced technologies and emerging industries.This paper first explains the concept of repetitive control from its original idea.Next,it describes the structure of a repetitive controller as an internal model and shows the respective points of continuous-and discrete-time repetitive control.It presents a categorized list of practical applications of repetitive control.Moreover,two concrete applications,namely the control of a robotic manipulator and a rotating system,demonstrate the validity of the method with experimental results.Several current studies in this field are also reviewed,and some challenges and future studies for repetitive control are provided. 展开更多
关键词 High-order repetitive control intelligent repetitive control internal-model principle modified repetitive control periodic signal repetitive control small-gain theorem spatial domain
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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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