Let n≥2 be a natural number,1≤p≤∞and X a Banach space.We prove that if X*containsλ-uniformly copies of lkp,then:P(nX) contains cKλn-uniformly copies of■.in the case p*>n(ii)P(nX) contain...Let n≥2 be a natural number,1≤p≤∞and X a Banach space.We prove that if X*containsλ-uniformly copies of lkp,then:P(nX) contains cKλn-uniformly copies of■.in the case p*>n(ii)P(nX) containsλn-uniformly copies of lk∞in the case p*≤n.This complete a result of S.Dineen’s from 1995.展开更多
Ultrafine metal nanoparticles are crucial for various applications,such as energy storage,catalysis,electronics,and biomedicine,owing to their high surfaceto-volume ratio and unique electronic properties.However,conve...Ultrafine metal nanoparticles are crucial for various applications,such as energy storage,catalysis,electronics,and biomedicine,owing to their high surfaceto-volume ratio and unique electronic properties.However,conventional nanoparticle synthesis methods often face challenges like irregular shapes and agglomeration,leading to compromised functionality.To address these challenges,this paper introduces a novel,rapid,high-temperature thermal radiation heating for the ultrafast synthesis and dispersion of metal nanoparticles.Utilizing the heating properties of carbon materials,the direct Joule heating generated by them rises to 1800-2000 K within~200 ms,followed by cooling to room temperature at a rate of 2×103K s-1.展开更多
In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities...In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them.展开更多
We study the evolution of spectral intensity and degree of coherence of a new class of partially coherent beams,Hermite non-uniformly correlated array beams,in free space and in turbulence,based on the extended Huygen...We study the evolution of spectral intensity and degree of coherence of a new class of partially coherent beams,Hermite non-uniformly correlated array beams,in free space and in turbulence,based on the extended Huygens–Fresnel integral.Such beams possess controllable rectangular grid distributions due to multi-self-focusing propagation property.Furthermore,it is demonstrated that adjusting the initial beam parameters,mode order,shift parameters,array parameters and correlation width plays a role in resisting intensity and degree of coherence degradation effects of the turbulence.展开更多
Based on one type of practical Biot's equation and the dynamic-stiffness matrices ofa poroelastic soil layer and half-space, Green's functions were derived for unitformly distributed loads acting on an inclined line...Based on one type of practical Biot's equation and the dynamic-stiffness matrices ofa poroelastic soil layer and half-space, Green's functions were derived for unitformly distributed loads acting on an inclined line in a poroelastie layered site. This analysis overcomes significant problems in wave scattering due to local soil conditions and dynamic soil-structure interaction. The Green's functions can be reduced to the case of an elastic layered site developed by Wolf in 1985. Parametric studies are then carried out through two example problems.展开更多
The uniformly ultimate boundedness of discontinuous systems with time-delay in the sense of Filippov solutions is discussed.Based on the Lyapunov-Krasovskii functional,the Lyapunov theorem for the globally strongly un...The uniformly ultimate boundedness of discontinuous systems with time-delay in the sense of Filippov solutions is discussed.Based on the Lyapunov-Krasovskii functional,the Lyapunov theorem for the globally strongly uniformly ultimate boundedness of retarded discontinuous systems is presented.Furthermore,the result is applied to a class of mechanical systems with a retarded discontinuous friction item.展开更多
The purpose of this paper is to study necessary and su?cient condition for the strong convergence of a new parallel iterative algorithm with errors for two finite families of uniformly L-Lipschitzian mappings in Bana...The purpose of this paper is to study necessary and su?cient condition for the strong convergence of a new parallel iterative algorithm with errors for two finite families of uniformly L-Lipschitzian mappings in Banach spaces. The results presented in this paper improve and extend the recent ones announced by [2–7].展开更多
We aim to study the thermodynamic properties of the spherically symmetric reference frames with uniform acceleration,including the spherically symmetric generalization of Rindler reference frame and the new kind of un...We aim to study the thermodynamic properties of the spherically symmetric reference frames with uniform acceleration,including the spherically symmetric generalization of Rindler reference frame and the new kind of uniformly accelerated reference frame.We find that,unlike the general studies about the horizon thermodynamics,one cannot obtain the laws of thermodynamics for their horizons in the usual approaches,despite that one can formally define an area entropy(Bekenstein-Hawking entropy).In fact,the common horizon for a set of uniformly accelerated observers does not always exist,even though the Hawking-Unruh temperature is still well-defined.This result indicates that the Hawking-Unruh temperature is only a kinematic effect,and to gain the laws of thermodynamics for the horizon,one needs the help of dynamics.Our result is in accordance with those from the various studies about the acoustic black holes.展开更多
In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman problem.Our formulation is based on velocity gradient-velocity-pressure and the resulting scheme ...In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman problem.Our formulation is based on velocity gradient-velocity-pressure and the resulting scheme can be flexibly applied to fairly general polygonal meshes.We relax the tangential continuity for velocity,which is the key ingredi-ent in achieving the uniform robustness.We present well-posedness and error analysis for both the semi-discrete scheme and the fully discrete scheme,and the theories indicate that the error estimates for velocity are independent of pressure.Several numerical experiments are presented to confirm the theoretical findings.展开更多
We present an overview of the properties of the pseudohyperbolic metric in several real dimensions and study uniformly discrete sequences for the real unit ball in R^n.
Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical meth...Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical method, under general cases, the Ishikawa iterative process {x(n)} converges strongly to the unique fixed point x* of the operator T were proved. The paper generalizes and extends a lot of recent corresponding results.展开更多
By using “the method of modified two-variable”,“the method of mixing perturbation” and introducing four small parameters,the problem of the nonlinear unsymmetrical bending for orthotropic rectangular thin plate wi...By using “the method of modified two-variable”,“the method of mixing perturbation” and introducing four small parameters,the problem of the nonlinear unsymmetrical bending for orthotropic rectangular thin plate with linear variable thickness is studied.And the uniformly valid asymptotic solution of Nth-order for ε_1 and Mth-order for ε_2 of the deflection functions and stress function are obtained.展开更多
In the present paper we introduce a random iteration scheme for three random operators defined on a closed and convex subset of a uniformly convex Banach space and prove its convergence to a common fixed point of thre...In the present paper we introduce a random iteration scheme for three random operators defined on a closed and convex subset of a uniformly convex Banach space and prove its convergence to a common fixed point of three random operators. The result is also an extension of a known theorem in the corresponding non-random case.展开更多
In this paper, we construct a class of difference schemes with fitted factors for a singular perturbation problem of a self-adjoint ordinary differential equation. Using a different method from [1], by analyzing the t...In this paper, we construct a class of difference schemes with fitted factors for a singular perturbation problem of a self-adjoint ordinary differential equation. Using a different method from [1], by analyzing the truncation errors of schemes, we give the sufficient conditions under which the solution of lite difference scheme converges uniformly to the solution of the differential equation. From this we propose several specific schemes under weaker conditions, and give much higher order of uniform convergence, and applying them to example, obtain the numerical results.展开更多
A general top system of two free dimensions with parameter is studied and the four cases satisfied by the frequency of the system are discussed.Using the multiple scale method,its uniformly valid asymptotic solution,w...A general top system of two free dimensions with parameter is studied and the four cases satisfied by the frequency of the system are discussed.Using the multiple scale method,its uniformly valid asymptotic solution,which is expressed by complex amplitudes,of the first order is obtained.And solvable conditions satisfied by the complex amplitudes are given,and then the relative result is generalized.展开更多
The authors consider the uniformly most powerful invariant test of the testing problems (Ⅰ) H 0: μ′Σ -1 μ≥CH 1: μ′Σ -1 μ<C and (Ⅱ) H 00 : β′X′Xβσ 2≥CH 11 : β′X′Xβσ 2<C under m dimension...The authors consider the uniformly most powerful invariant test of the testing problems (Ⅰ) H 0: μ′Σ -1 μ≥CH 1: μ′Σ -1 μ<C and (Ⅱ) H 00 : β′X′Xβσ 2≥CH 11 : β′X′Xβσ 2<C under m dimensional normal population N m(μ, Σ) and normal linear model (Y, Xβ, σ 2) respectively. Furthermore, an application of the uniformly most powerful invariant test is given.展开更多
The fixed points of set-valued operators satisfying a condition of monotonicitytype in s-uniformly smooth Banach spaces are approximated by recursive averagingprocess in the present paper.
We discuss the uniformly higher order accurate extrapolations, which are based on the uniform expansion for global error, to solutions of uniformly convergent discretization methods for singularly perturbed problems. ...We discuss the uniformly higher order accurate extrapolations, which are based on the uniform expansion for global error, to solutions of uniformly convergent discretization methods for singularly perturbed problems. By applying the approach to the in-Allen-Southwell scheme for a non-self-adjoint problem, we obtain an extrapolation solution which is uniformly convergent with order two. We confirm the result by numerical calculations.展开更多
In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniform...In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniformly convergent second order scheme.展开更多
An uncertainty analysis method is proposed for the assessment of the residual strength of a casing subjected to wear and non-uniform load in a deep well.The influence of casing residual stress,out-of-roundness and non...An uncertainty analysis method is proposed for the assessment of the residual strength of a casing subjected to wear and non-uniform load in a deep well.The influence of casing residual stress,out-of-roundness and non-uniform load is considered.The distribution of multi-source parameters related to the residual anti extrusion strength and residual anti internal pressure strength of the casing after wear are determined using the probability theory.Considering the technical casing of X101 well in Xinjiang Oilfield as an example,it is shown that the randomness of casing wear depth,formation elastic modulus and formation Poisson’s ratio are the main factors that affect the uncertainty of residual strength.The wider the confidence interval is,the greater the uncertainty range is.Compared with the calculations resulting from the proposed uncertainty analysis method,the residual strength obtained by means of traditional single value calculation method is either larger or smaller,which leads to the conclusion that the residual strength should be considered in terms of a range of probabilities rather than a single value.展开更多
摘要Let n≥2 be a natural number,1≤p≤∞and X a Banach space.We prove that if X*containsλ-uniformly copies of lkp,then:P(nX) contains cKλn-uniformly copies of■.in the case p*>n(ii)P(nX) containsλn-uniformly copies of lk∞in the case p*≤n.This complete a result of S.Dineen’s from 1995.
基金financially supported by the National Natural Science Foundation of China(Nos.22468029,52274408,52204314)the Major Science and Technology Projects in Yunnan Province(No.202402AF080005)+1 种基金Yunnan Fundamental Research Projects(No.202201AW070014)the Program for Innovative Research Team in the University of ministry of Education of China(No.IRT_17R48)
摘要Ultrafine metal nanoparticles are crucial for various applications,such as energy storage,catalysis,electronics,and biomedicine,owing to their high surfaceto-volume ratio and unique electronic properties.However,conventional nanoparticle synthesis methods often face challenges like irregular shapes and agglomeration,leading to compromised functionality.To address these challenges,this paper introduces a novel,rapid,high-temperature thermal radiation heating for the ultrafast synthesis and dispersion of metal nanoparticles.Utilizing the heating properties of carbon materials,the direct Joule heating generated by them rises to 1800-2000 K within~200 ms,followed by cooling to room temperature at a rate of 2×103K s-1.
基金supported by the NNSF of China(11001074,11061015,11101124)the Foundation for University Young Key Teacher of Henan Province
摘要In this article, we extend the definition of uniformly starlike functions and uni- formly convex functions on the unit disk to the unit ball in C^n, give the discriminant criterions for them, and get some inequalities for them.
基金the National Key Research and Development Program of China(Grant No.2019YFA0705000)the National Natural Science Foundation of China(Grant Nos.91750201,11525418,11947240,11974218,12004218,and 11904087)+1 种基金the Local Science and Technology Development Project of the Central Government(Grant No.YDZX20203700001766)Innovation Group of Jinan(Grant No.2018GXRC010)。
摘要We study the evolution of spectral intensity and degree of coherence of a new class of partially coherent beams,Hermite non-uniformly correlated array beams,in free space and in turbulence,based on the extended Huygens–Fresnel integral.Such beams possess controllable rectangular grid distributions due to multi-self-focusing propagation property.Furthermore,it is demonstrated that adjusting the initial beam parameters,mode order,shift parameters,array parameters and correlation width plays a role in resisting intensity and degree of coherence degradation effects of the turbulence.
基金National Natural Science Foundation of China Under Grant No.50378063
摘要Based on one type of practical Biot's equation and the dynamic-stiffness matrices ofa poroelastic soil layer and half-space, Green's functions were derived for unitformly distributed loads acting on an inclined line in a poroelastie layered site. This analysis overcomes significant problems in wave scattering due to local soil conditions and dynamic soil-structure interaction. The Green's functions can be reduced to the case of an elastic layered site developed by Wolf in 1985. Parametric studies are then carried out through two example problems.
基金supported by the National Natural Science Foundation of China (No. 60874006)
摘要The uniformly ultimate boundedness of discontinuous systems with time-delay in the sense of Filippov solutions is discussed.Based on the Lyapunov-Krasovskii functional,the Lyapunov theorem for the globally strongly uniformly ultimate boundedness of retarded discontinuous systems is presented.Furthermore,the result is applied to a class of mechanical systems with a retarded discontinuous friction item.
基金supported by the National Natural Science Foun-dation of China (11071169)the Natural Science Foundation of Zhejiang Province (Y6110287)
摘要The purpose of this paper is to study necessary and su?cient condition for the strong convergence of a new parallel iterative algorithm with errors for two finite families of uniformly L-Lipschitzian mappings in Banach spaces. The results presented in this paper improve and extend the recent ones announced by [2–7].
基金The project supported by National Natural Science Foundation of China under Grant Nos.90403023,10375087,and 10775140
摘要We aim to study the thermodynamic properties of the spherically symmetric reference frames with uniform acceleration,including the spherically symmetric generalization of Rindler reference frame and the new kind of uniformly accelerated reference frame.We find that,unlike the general studies about the horizon thermodynamics,one cannot obtain the laws of thermodynamics for their horizons in the usual approaches,despite that one can formally define an area entropy(Bekenstein-Hawking entropy).In fact,the common horizon for a set of uniformly accelerated observers does not always exist,even though the Hawking-Unruh temperature is still well-defined.This result indicates that the Hawking-Unruh temperature is only a kinematic effect,and to gain the laws of thermodynamics for the horizon,one needs the help of dynamics.Our result is in accordance with those from the various studies about the acoustic black holes.
基金the Hong Kong RGC General Research Fund(Project numbers 14304719 and 14302018)CUHK Faculty of Science Direct Grant 2019-20。
摘要In this paper,we propose and analyze a uniformly robust staggered DG method for the unsteady Darcy-Forchheimer-Brinkman problem.Our formulation is based on velocity gradient-velocity-pressure and the resulting scheme can be flexibly applied to fairly general polygonal meshes.We relax the tangential continuity for velocity,which is the key ingredi-ent in achieving the uniform robustness.We present well-posedness and error analysis for both the semi-discrete scheme and the fully discrete scheme,and the theories indicate that the error estimates for velocity are independent of pressure.Several numerical experiments are presented to confirm the theoretical findings.
基金supported by the NNSF of China(11071230,11371337)RFDP(20123402110068)+2 种基金supported by FEDER funds through COMPETE–Operational Programme Factors of Competitiveness(Programa Operacional Factores de Competitividade)Portuguese funds through the Center for Research and Development in Mathematics and Applications(University of Aveiro)the Portuguese Foundation for Science and Technology(FCT–Fundaao para a Ciêencia e a Tecnologia),within project PEst-C/MAT/UI4106/2011 with COMPETE number FCOMP-01-0124-FEDER-022690
摘要We present an overview of the properties of the pseudohyperbolic metric in several real dimensions and study uniformly discrete sequences for the real unit ball in R^n.
摘要Let E be a uniformly smooth Banach space, K be a nonempty closed convex subset of E, and suppose: T: K --> K is a continuous Phi-strongly pseudocontractive operator with a bounded range. Using a new analytical method, under general cases, the Ishikawa iterative process {x(n)} converges strongly to the unique fixed point x* of the operator T were proved. The paper generalizes and extends a lot of recent corresponding results.
摘要By using “the method of modified two-variable”,“the method of mixing perturbation” and introducing four small parameters,the problem of the nonlinear unsymmetrical bending for orthotropic rectangular thin plate with linear variable thickness is studied.And the uniformly valid asymptotic solution of Nth-order for ε_1 and Mth-order for ε_2 of the deflection functions and stress function are obtained.
摘要In the present paper we introduce a random iteration scheme for three random operators defined on a closed and convex subset of a uniformly convex Banach space and prove its convergence to a common fixed point of three random operators. The result is also an extension of a known theorem in the corresponding non-random case.
摘要In this paper, we construct a class of difference schemes with fitted factors for a singular perturbation problem of a self-adjoint ordinary differential equation. Using a different method from [1], by analyzing the truncation errors of schemes, we give the sufficient conditions under which the solution of lite difference scheme converges uniformly to the solution of the differential equation. From this we propose several specific schemes under weaker conditions, and give much higher order of uniform convergence, and applying them to example, obtain the numerical results.
基金Supported by the NNSF of China(10471039)Supported by the Natural Science Foundation of Zhejiang Province(Y606268)Supported by the E-Institutes of Shanghai Municipal Education Commission(E03004)
摘要A general top system of two free dimensions with parameter is studied and the four cases satisfied by the frequency of the system are discussed.Using the multiple scale method,its uniformly valid asymptotic solution,which is expressed by complex amplitudes,of the first order is obtained.And solvable conditions satisfied by the complex amplitudes are given,and then the relative result is generalized.
摘要The authors consider the uniformly most powerful invariant test of the testing problems (Ⅰ) H 0: μ′Σ -1 μ≥CH 1: μ′Σ -1 μ<C and (Ⅱ) H 00 : β′X′Xβσ 2≥CH 11 : β′X′Xβσ 2<C under m dimensional normal population N m(μ, Σ) and normal linear model (Y, Xβ, σ 2) respectively. Furthermore, an application of the uniformly most powerful invariant test is given.
摘要The fixed points of set-valued operators satisfying a condition of monotonicitytype in s-uniformly smooth Banach spaces are approximated by recursive averagingprocess in the present paper.
基金Supported by the National Natural Science Foundation of China
摘要We discuss the uniformly higher order accurate extrapolations, which are based on the uniform expansion for global error, to solutions of uniformly convergent discretization methods for singularly perturbed problems. By applying the approach to the in-Allen-Southwell scheme for a non-self-adjoint problem, we obtain an extrapolation solution which is uniformly convergent with order two. We confirm the result by numerical calculations.
摘要In this paper, based on the idea of El-Mistikawy and Werle[1] we construct a difference scheme for a singularly perturbed self-adjoint ordinary differential equation in conservation form. We prove that it is a uniformly convergent second order scheme.
基金supported by the National Natural Science Foundation of China[51804061,51974052,51774063]the Academician Led Special Project of Chongqing Science and Technology Commission[cstc2017zdcy-yszxX0009]+1 种基金the Chongqing Research Program of Basic Research and Frontier Technology[cstc2019jcyj-msxmX0199,cstc2018jcyjAX0417]the Chongqing Education Committee foundation[KJQN201901544,KJZD-K201801501].
摘要An uncertainty analysis method is proposed for the assessment of the residual strength of a casing subjected to wear and non-uniform load in a deep well.The influence of casing residual stress,out-of-roundness and non-uniform load is considered.The distribution of multi-source parameters related to the residual anti extrusion strength and residual anti internal pressure strength of the casing after wear are determined using the probability theory.Considering the technical casing of X101 well in Xinjiang Oilfield as an example,it is shown that the randomness of casing wear depth,formation elastic modulus and formation Poisson’s ratio are the main factors that affect the uncertainty of residual strength.The wider the confidence interval is,the greater the uncertainty range is.Compared with the calculations resulting from the proposed uncertainty analysis method,the residual strength obtained by means of traditional single value calculation method is either larger or smaller,which leads to the conclusion that the residual strength should be considered in terms of a range of probabilities rather than a single value.