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LONG TIME EXISTENCE FOR THE NON-ISENTROPIC SLIGHTLY COMPRESSIBLE FLUID MODEL OF KORTEWEG TYPE
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作者 Qiangchang JU Jianjun XU 《Acta Mathematica Scientia》 2025年第2期416-445,共30页
We investigate the long time existence of strong solutions to the initial value problem for the three-dimensional non-isentropic compressible Navier-Stokes-Korteweg system.Under the conditions of slight density and te... We investigate the long time existence of strong solutions to the initial value problem for the three-dimensional non-isentropic compressible Navier-Stokes-Korteweg system.Under the conditions of slight density and temperature variations,we verify that the full compressible Navier-Stokes-Korteweg equations admit a unique strong solution as long as the solution of the limiting system exists,when the Mach number is sufficiently small.Furthermore,we deduce the uniform convergence of strong solutions for the compressible system toward those for the corresponding incompressible system on the time interval in which the solution exists. 展开更多
关键词 non-isentropic compressible Navier-Stokes-Korteweg equations low Mach num-ber limit long time existence strong solution
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THE GLOBAL EXISTENCE AND UNIQUENESS OF SMOOTH SOLUTIONS TO A FLUID-PARTICLE INTERACTION MODEL IN THE FLOWING REGIME
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作者 Lin ZHENG Shu WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1877-1885,共9页
This paper is concerned with the Cauchy problem for a 3D fluid-particle interaction model in the so-called flowing regime inℝ3.Under the smallness assumption on both the external potential and the initial perturbation... This paper is concerned with the Cauchy problem for a 3D fluid-particle interaction model in the so-called flowing regime inℝ3.Under the smallness assumption on both the external potential and the initial perturbation of the stationary solution in some Sobolev spaces,the existence and uniqueness of global smooth solutions in H3 of the system are established by using the careful energy method. 展开更多
关键词 fluid-particle flowing regime global existence
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THE GLOBAL EXISTENCE OF STRONG SOLUTIONS TO THERMOMECHANICAL CUCKER-SMALE-STOKES EQUATIONS IN THE WHOLE DOMAIN
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作者 邹委员 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期887-908,共22页
We study the global existence and uniqueness of a strong solution to the kinetic thermomechanical Cucker-Smale(for short,TCS) model coupled with Stokes equations in the whole space.The coupled system consists of the k... We study the global existence and uniqueness of a strong solution to the kinetic thermomechanical Cucker-Smale(for short,TCS) model coupled with Stokes equations in the whole space.The coupled system consists of the kinetic TCS equation for a particle ensemble and the Stokes equations for a fluid via a drag force.In this paper,we present a complete analysis of the existence of global-in-time strong solutions to the coupled model without any smallness restrictions on the initial data. 展开更多
关键词 thermomechanical Cucker-Smale model Stokes equations strong solutions global existence
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The Existence of Solutions for Kirchhoff-Type Equations with General Singular Terms
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作者 WANG Ji-nan SUN Da-wei 《Chinese Quarterly Journal of Mathematics》 2024年第3期315-323,共9页
We study the existence of solutions for Kirchhoff-type equations.Firstly,we use the Sobolev inequality and the weakly lower semi-continuity of the norm to prove that the corresponding function can reach the global min... We study the existence of solutions for Kirchhoff-type equations.Firstly,we use the Sobolev inequality and the weakly lower semi-continuity of the norm to prove that the corresponding function can reach the global minimum.Then,we use the variational method and some analytical techniques to obtain the existence of the positive solution of the equation whenλis small enough. 展开更多
关键词 Kirchhoff-type equation The existence Positive solution Variational method
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being、essence和existence——托马斯·阿奎那存在论思想探析 被引量:1
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作者 刘素民 《武汉大学学报(人文科学版)》 CSSCI 北大核心 2010年第6期720-727,共8页
托马斯.阿奎那的形而上学是以是(being)为中心、以本质(essence)和存在(existence)的关系学说为枢纽的存在论。阿奎那认为,形而上学或存在论所探讨的特殊的固有对象即是是(to on,esse,being)自身,或者称之为是之所以为是(esse in quantu... 托马斯.阿奎那的形而上学是以是(being)为中心、以本质(essence)和存在(existence)的关系学说为枢纽的存在论。阿奎那认为,形而上学或存在论所探讨的特殊的固有对象即是是(to on,esse,being)自身,或者称之为是之所以为是(esse in quantum esse,being as beinginjeneral)。他在论证是自身时强调实在意义上的是重于逻辑意义的是。是(being)包括本质(essence)与存在(existence);本质(essence)与存在(existence)皆为是者(beings)。而存在(existence)先于本质(essence);存在(existence)是是(being)之最具体的、个别的、实体的、独一无二的完美实现(act)。托马斯.阿奎那的存在论哲学颠覆了传统哲学中存在与本质的位置,它以一种存在主义代替本质主义,从而在形而上学历史上掀起一场革命。 展开更多
关键词 BEING ESSENCE existENCE
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The Existence of Generalized Solutions for a Nonhomogeneous Boundary Value Problem
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作者 孙应飞 周美珂 范天佑 《Journal of Beijing Institute of Technology》 EI CAS 1998年第3期210-214,共5页
Aim The existence of generalized solution for a class of nonlinear partial differential equations with nonhanogeneous boundary condition was investigated. This problem arises from polymer processing concerned with the... Aim The existence of generalized solution for a class of nonlinear partial differential equations with nonhanogeneous boundary condition was investigated. This problem arises from polymer processing concerned with the first initial-boundary value problem or the nonstationary floW of non-Newtonian viscous incompressiblee fluid through the slit dice. MethodsThe monotone operator theory and the Schauder's fixal point theorem were used. Results and Conclusion The existence theorem of generalized solutions for a the of nonlinear partial differential equations with nonhormogeneous boundary condition is proved under reasonable conditions 展开更多
关键词 Navier-Stokes equation monotone operator existENCE
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Existence of Positive Solutions for Nonlinear Conjugate Boundary Value Problems
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作者 菅典兵 董正华 《Chinese Quarterly Journal of Mathematics》 CSCD 2002年第2期87-93,共7页
The present paper is concerned with the existence of positive solutions of the (k,n-k) conjugate boundary value problems(-1) n-k u (h) (t)=λa(t)f(u(t)),t∈(0,1), u (i) (0)=0,0≤i≤k-1, u (j) (0)=0,0... The present paper is concerned with the existence of positive solutions of the (k,n-k) conjugate boundary value problems(-1) n-k u (h) (t)=λa(t)f(u(t)),t∈(0,1), u (i) (0)=0,0≤i≤k-1, u (j) (0)=0,0≤j≤n-k-1,where λ is a positive parmeter. Krasnoselsii’s fixed point theorem is employed to obtain the existence criteria for positive solution. 展开更多
关键词 existence theorem positive solutions conjugate boundary value problem
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An Existence Theorem of Positive Solution for Fourth-order Superlinear Semipositone Eigenvalue Problems
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作者 江秀芬 姚庆六 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第2期64-68,共5页
In this paper we investigate the existence of positive solution for a class of fourth_order superlinear semipositone eigenvalue problems. This class of problems usually describes the deformation of the elastic beam wh... In this paper we investigate the existence of positive solution for a class of fourth_order superlinear semipositone eigenvalue problems. This class of problems usually describes the deformation of the elastic beam whose both end_points are fixed. 展开更多
关键词 elastic beam equation existence of positive solution SEMIPOSITONE fixed point theorem on cone
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EXISTENCE AND NONEXISTENCE OF GLOBAL SOLUTIONS FOR A SEMI-LINEAR HEAT EQUATION WITH FRACTIONAL LAPLACIAN
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作者 谭忠 许勇强 《Acta Mathematica Scientia》 SCIE CSCD 2012年第6期2203-2210,共8页
In this paper, we are concerned with the existence and non-existence of global solutions of a semi-linear heat equation with fractional Laplacian. We obtain some extem sion of results of Weissler who considered the ca... In this paper, we are concerned with the existence and non-existence of global solutions of a semi-linear heat equation with fractional Laplacian. We obtain some extem sion of results of Weissler who considered the case α = 1, and h ≡ 1. 展开更多
关键词 fractional Laplacian equation global existence NONexistENCE
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China English——An Objective Existence as a Performance Variety
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作者 黄春燕 《语言与文化研究》 2008年第1期187-192,共6页
China English is an objective existence as a performance variety used in China.It is based on standard English and possesses Chinese characteristics.The Chinese characteristics of China English are reflected in the ph... China English is an objective existence as a performance variety used in China.It is based on standard English and possesses Chinese characteristics.The Chinese characteristics of China English are reflected in the phonology,vocabulary,syntax,rhetoric and text,particularly in the vocabulary.This essay will discuss the features of China English from the following three aspects: the development of English in China;the comparison between China English,Pidgin English and Chinese English and the Chinese words borrowed by English. 展开更多
关键词 China ENGLISH objective existENCE PERFORMANCE VARI
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SUFFICIENT AND NECESSARY CONDITIONS ON THE EXISTENCE AND ESTIMATES OF BOUNDARY BLOW-UP SOLUTIONS FOR SINGULAR p-LAPLACIAN EQUATIONS
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作者 张学梅 阚士坤 《Acta Mathematica Scientia》 SCIE CSCD 2023年第3期1175-1194,共20页
Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we pro... Let?denote a smooth,bounded domain in R^(N)(N≥2).Suppose that g is a nondecreasing C^(1)positive function and assume that b(x)is continuous and nonnegative inΩ,and that it may be singular on■Ω.In this paper,we provide sufficient and necessary conditions on the existence of boundary blow-up solutions to the p-Laplacian problem△_(p)u=b(x)g(u)for x∈Ω,u(x)→+∞as dist(x,■Ω)→0.The estimates of such solutions are also investigated.Moreover,when b has strong singularity,the nonexistence of boundary blow-up(radial)solutions and infinitely many radial solutions are also considered. 展开更多
关键词 singular p-Laplacian equation boundary blow-up sub-supersolution method existENCE nonexistence and estimates sufficient and necessary conditions
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ON THE EXISTENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n=Q to (F(x,u,Du))+integral from n=■Q to (G(x,u))
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作者 严树森 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期231-240,共10页
In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o... In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o to u (g(x,t)dt), under the weak structure conditions on F(x, u, q) by the Mountain Pass Lemma. 展开更多
关键词 ON THE existENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n=Q to x u Du ON THE existENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n Q to x u
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GLOBAL EXISTENCE, UNIFORM DECAY AND EXPONENTIAL GROWTH FOR A CLASS OF SEMI-LINEAR WAVE EQUATION WITH STRONG DAMPING 被引量:7
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作者 陈化 刘功伟 《Acta Mathematica Scientia》 SCIE CSCD 2013年第1期41-58,共18页
In this paper, we consider the nonlinearly damped semi-linear wave equation associated with initial and Dirichlet boundary conditions. We prove the existence of a local weak solution and introduce a family of potentia... In this paper, we consider the nonlinearly damped semi-linear wave equation associated with initial and Dirichlet boundary conditions. We prove the existence of a local weak solution and introduce a family of potential wells and discuss the invariants and vacuum isolating behavior of solutions. Furthermore, we prove the global existence of solutions in both cases which are polynomial and exponential decay in the energy space respectively, and the asymptotic behavior of solutions for the cases of potential well family with 0 〈 E(0) 〈 d. At last we show that the energy will grow up as an exponential function as time goes to infinity, provided the initial data is large enough or E(0) 〈 0. 展开更多
关键词 strong damping nonlinear damping global existence polynomial decay exponential decay exponential growth
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EXISTENCE OF POSITIVE PERIODIC SOLUTIONS FOR VOLTERRA INTERGO-DIFFERENTIAL EQUATIONS 被引量:8
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作者 蒋达清 魏俊杰 《Acta Mathematica Scientia》 SCIE CSCD 2001年第4期553-560,共8页
This paper deals with the existence of positive periodic solutions for a kind of nonautonomous Volterra intergo-differential equations by employing the Krasnoselskii fixed point theorem. Applying the general theorems ... This paper deals with the existence of positive periodic solutions for a kind of nonautonomous Volterra intergo-differential equations by employing the Krasnoselskii fixed point theorem. Applying the general theorems established to several biomathematical models, the paper improves some previous results and obtains some new results. 展开更多
关键词 Volterra integro-differential equation existENCE positive periodic solution fixed point theorem
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ON THE EXISTENCE AND STABILITY OF BOUNDARY VALUE PROBLEM FOR DIFFERENTIAL EQUATION WITH HILFER-KATUGAMPOLA FRACTIONAL DERIVATIVE 被引量:5
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作者 E.M.ELSAYED S.HARIKRISHNAN K.KANAGARAJAN 《Acta Mathematica Scientia》 SCIE CSCD 2019年第6期1568-1578,共11页
In this paper, we discuss the existence, uniqueness and stability of boundary value problem for differential equation with Hilfer-Katugampola fractional derivative. The arguments are based upon Schaefer's fixed po... In this paper, we discuss the existence, uniqueness and stability of boundary value problem for differential equation with Hilfer-Katugampola fractional derivative. The arguments are based upon Schaefer's fixed point theorem, Banach contraction principle and Ulam type stability. 展开更多
关键词 Hilfer-Katugampola fractional DERIVATIVE boundary condition existENCE Ulam STABILITY
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THE EXISTENCE OF NONTRIVIAL SOLUTIONS TO A SEMILINEAR ELLIPTIC SYSTEM ON R N WITHOUT THE AMBROSETTI-RABINOWITZ CONDITION 被引量:7
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作者 李工宝 王春花 《Acta Mathematica Scientia》 SCIE CSCD 2010年第6期1917-1936,共20页
In this paper, we prove the existence of at least one positive solution pair (u, v)∈ H1(RN) × H1(RN) to the following semilinear elliptic system {-△u+u=f(x,v),x∈RN,-△u+u=g(x,v),x∈RN (0.1),by us... In this paper, we prove the existence of at least one positive solution pair (u, v)∈ H1(RN) × H1(RN) to the following semilinear elliptic system {-△u+u=f(x,v),x∈RN,-△u+u=g(x,v),x∈RN (0.1),by using a linking theorem and the concentration-compactness principle. The main conditions we imposed on the nonnegative functions f, g ∈C0(RN× R1) are that, f(x, t) and g(x, t) are superlinear at t = 0 as well as at t =+∞, that f and g are subcritical in t and satisfy a kind of monotonic conditions. We mention that we do not assume that f or g satisfies the Ambrosetti-Rabinowitz condition as usual. Our main result can be viewed as an extension to a recent result of Miyagaki and Souto [J. Diff. Equ. 245(2008), 3628-3638] concerning the existence of a positive solution to the semilinear elliptic boundary value problem {-△u+u=f(x,u),x∈Ω,u∈H0^1(Ω) where Ω ∩→RN is bounded and a result of Li and Yang [G. Li and J. Yang: Communications in P.D.E. Vol. 29(2004) Nos.5& 6.pp.925-954, 2004] concerning (0.1) when f and g are asymptotically linear. 展开更多
关键词 existENCE nontrivial solution semilinear elliptic system without the (AR) condition
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THE LOCAL AND GLOBAL EXISTENCE OF THE SOLUTIONS OF HYPERBOLIC-PARABOLIC SYSTEM MODELING BIOLOGICAL PHENOMENA 被引量:6
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作者 吴少华 陈化 李维喜 《Acta Mathematica Scientia》 SCIE CSCD 2008年第1期101-116,共16页
The authors prove the local existence and uniqueness of weak solution of a hyperbolic-parabolic system and establish the global existence of the weak solution for this system for the spatial dimension n = 1.
关键词 Hyperbolic-parabolic system chemosensitive movement external signal global existence
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BLOW-UP AND GLOBAL EXISTENCE FOR A COUPLED SYSTEM OF DEGENERATE PARABOLIC EQUATIONS IN A BOUNDED DOMAIN 被引量:7
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作者 穆春来 胡学刚 +1 位作者 李玉环 崔泽键 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期92-106,共15页
This article deals with the conditions that ensure the blow-up phenomenon or its absence for solutions of the system ut= △u^l + u^p1v^q1 and vt = △v ^m + u^p2 v^q2 with homogeneous Dirichlet boundary conditions.... This article deals with the conditions that ensure the blow-up phenomenon or its absence for solutions of the system ut= △u^l + u^p1v^q1 and vt = △v ^m + u^p2 v^q2 with homogeneous Dirichlet boundary conditions. The results depend crucially on the sign of the difference p2q1 - (l -p1)(m- q2), the initial data, and the domain Ω. 展开更多
关键词 Global existence BLOW-UP degenerate parabolic system
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A NECESSARY AND A SUFFICIENT CONDITION FOR THE EXISTENCE OF THE POSITIVE RADIAL SOLUTIONS TO HESSIAN EQUATIONS AND SYSTEMS WITH WEIGHTS 被引量:7
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作者 Dragos-Patru COVEI 《Acta Mathematica Scientia》 SCIE CSCD 2017年第1期47-57,共11页
In this article, we consider the existence of positive radial solutions for Hessian equations and systems with weights and we give a necessary condition as well as a sufficient condition for a positive radial solution... In this article, we consider the existence of positive radial solutions for Hessian equations and systems with weights and we give a necessary condition as well as a sufficient condition for a positive radial solution to be large. The method of proving theorems is essentially based on a successive approximation technique. Our results complete and improve a work published recently by Zhang and Zhou(existence of entire positive k-convex radial solutions to Hessian equations and systems with weights. Applied Mathematics Letters,Volume 50, December 2015, Pages 48–55). 展开更多
关键词 existENCE Keller-Osserman condition k-Hessian equation and system
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EXISTENCE AND CONTROLLABILITY FOR NONLINEAR FRACTIONAL CONTROL SYSTEMS WITH DAMPING IN HILBERT SPACES 被引量:4
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作者 Xiuwen LI Zhenhai LIU +1 位作者 Jing LI Chris TISDELL 《Acta Mathematica Scientia》 SCIE CSCD 2019年第1期229-242,共14页
In this paper, we are concerned with the existence of mild solution and controllability for a class of nonlinear fractional control systems with damping in Hilbert spaces.Our first step is to give the representation o... In this paper, we are concerned with the existence of mild solution and controllability for a class of nonlinear fractional control systems with damping in Hilbert spaces.Our first step is to give the representation of mild solution for this control system by utilizing the general method of Laplace transform and the theory of(α, γ)-regularized families of operators. Next, we study the solvability and controllability of nonlinear fractional control systems with damping under some suitable sufficient conditions. Finally, two examples are given to illustrate the theory. 展开更多
关键词 existENCE controllability fractional control systems DAMPING REGULARIZED RESOLVENT family
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