O-convexity of Orlicz-Bochner Spaces with Orlicz Norm

In this paper we give some characterizations of O-convexity of Banach spaces, and show the criteria for O-convexity in Orlicz-Bochner function space L_M(μ, X) and Orlicz-Bochner sequence space l_M(X_s) endowed with Orlicz norm.Moreover, we give a sufficient condition for the dual of such a space to have the fixed point property.     

RESEARCH ANNOUNCEMENTS Morrey Regularity of the Solutionto the Dirichlet Problem

To study the local regularity of solutions to second order elliptic partial differential equations, Morrey in [1] introduced some function spaces, which are called the Morrey spaces todaySince then, many mathematicians have studied regularities of solutions to some kinds of secondorder elliptic equations in Morrey spaces.We give the deceptions of Morrey space and weak Morrey space first.Definition 1 Let TheThesubset of those functions of Lp for which will be called the Morrey space LpDefi…     

A generalization of Hardy spaces <Emphasis Type="Italic">H</Emphasis><Superscript><Emphasis Type="Italic">p</Emphasis></Superscript> by using atoms

Let X = （X, d,μ） The purpose of this paper is to be a space of homogeneous type in the sense of Coifman and Weiss. generalize the definition of Hardy space H^P（X） and prove that the generalized Hardy spaces have the same property as H^P（X）. Our definition includes a kind of Hardy- Orlicz spaces and a kind of Hardy spaces with variable exponent. The results are new even for the R^n case. Let （X, δ, μ） be the normalized space of （X, d, μ） in the sense of Macias and Segovia. We also study the relations of our function spaces for （X, d, μ） and （X, δ,μ）.     

Weakly Compact Sets and Riesz Representation Theorem in Musielak Sequence Spaces

In this work, we give some criteria of the weakly compact sets and a representation theorem of Riesz’s type in Musielak sequence spaces using the ideas and techniques of sequence spaces and Musielak function. Finally, as an immediate consequence of the criteria considered in this paper, the criteria of the weakly compact sets of Orlicz sequence spaces are deduced.     

RESEARCH ANNOUNCEMENTS：Morrey Regularity of the Solution to the Diri

To study the local regularity of solutions to second orderelliptic partial differential equations, Morrey in ［1］ introduced somefunction spaces, which are called the Morrey spaces today. Since then, manymathematicians have studied regularities of solutions to some kinds of secondorder elliptic equations in Morrey spaces.     

A Survey of the Homotopy Properties of Inclusion of Certain Types of Configuration Spaces into the Cartesian Product

Let X be a topological space.In this survey the authors consider several types of configuration spaces,namely,the classical(usual)configuration spaces F_n(X)and D_n(X),the orbit configuration spaces F_n~G(X)and F_n~G(X)/S_nwith respect to a free action of a group G on X,and the graph configuration spaces F_n~Γ(X)and F_n~Γ(X)/H,whereΓis a graph and H is a suitable subgroup of the symmetric group S_n.The ordered configuration spaces F_n(X),F_n~G(X),F_n~Γ(X)are all subsets of the n-fold Cartesian product ∏_1~nX of X with itself,and satisfy F_n~G(X)?F_n(X)?F_n~Γ(X)?∏_1~nX.If A denotes one of these configuration spaces,the authors analyse the difference between A and ∏_1~nXfrom a topological and homotopical point of view.The principal results known in the literature concern the usual configuration spaces.The authors are particularly interested in the homomorphism on the level of the homotopy groups of the spaces induced by the inclusionι:A-→∏_1~nX,the homotopy type of the homotopy fibre I_ιof the mapιvia certain constructions on various spaces that depend on X,and the long exact sequence in homotopy of the fibration involving I_ιand arising from the inclusionι.In this respect,if X is either a surface without boundary,in particular if X is the 2-sphere or the real projective plane,or a space whose universal covering is contractible,or an orbit space S~k/Gof the k-dimensional sphere by a free action of a Lie group G,the authors present recent results obtained by themselves for the first case,and in collaboration with Golasi′nski for the second and third cases.The authors also briefly indicate some older results relative to the homotopy of these spaces that are related to the problems of interest.In order to motivate various questions,for the remaining types of configuration spaces,a few of their basic properties are described and proved.A list of open questions and problems is given at the end of the paper.     

EXTREME POINTS AND STRICT CONVEXITY OF VECTOR VALUED ORLICZ SPACES

The theory of vector valued Orlicz spaces generated by parametric N-functions is investigated in[1,2,3,4,].In this paper,a sufficient and neces-sary.coadition of extreme points of the unit ball of those spaces is given,and a criterion of the strict convexity of the spaces is obtained.     

Weak Morrey spaces and strong solutions to the Navier-Stokes equations

We consider the Cauchy problem of Navier-Stokes equations in weak Morrey spaces. We first define a class of weak Morrey type spaces Mp*,λ(Rn) on the basis of Lorentz space Lp,∞ = Lp*(Rn)(in particular, Mp*,0(Rn) = Lp,∞, if p ＞ 1), and study some fundamental properties of them; Second,bounded linear operators on weak Morrey spaces, and establish the bilinear estimate in weak Morrey spaces. Finally, by means of Kato's method and the contraction mapping principle, we prove that the Cauchy problem of Navier-Stokes equations in weak Morrey spaces Mp*,λ(Rn) (1＜p≤n) is time-global well-posed, provided that the initial data are sufficiently small. Moreover, we also obtain the existence and uniqueness of the self-similar solution for Navier-Stokes equations in these spaces, because the weak Morrey space Mp*,n-p(Rn) can admit the singular initial data with a self-similar structure. Hence this paper generalizes Kato's results.     

A survey on Fourier analysis methods for solving the compressible Navier-Stokes equations

Fourier analysis methods and in particular techniques based on Littlewood-Paley decomposition and paraproduct have known a growing interest recently for the study of nonlinear evolutionary equations.In this survey paper,we explain how these methods may be implemented so as to study the compresible Navier-Stokes equations in the whole space.We shall investigate both the initial value problem in critical Besov spaces and the low Mach number asymptotics.     

Weak Orlicz space and its applications to the martingale theory

In this paper,the weak Orlicz space wL Φ is introduced and its applications to the martingale theory are discussed.In particular,a series of martingale inequalities including the maximal function inequality in weak Orlicz spaces are established;the relationships between these spaces are investigated.Moreover,the boundedness of several sublinear operators from one weak Orlicz space to another is proved;their vector-valued analogues are also considered.     

Weighted Best Local Approximation

In this survey the notion of a balanced best multipoint local approximation is fully exposed since they were treated in the Lp spaces and recent results in Orlicz spaces.The notion of balanced point,introduced by Chui et al.in 1984 are extensively used.     

THE BOUNDEDNESS OF SOME INTEGRAL OPERATORS IN A NEW CLASS OF FUNCTION SPACES

A new class of function spaces, denoted by Ba, was introduced in [1]. It includes not only some familiar Orlicz spaces, Orlicz-Sobolev spaces but also some useful new function spaces. Ba spaces have gotten many applications (see, for example,[1-3]). In this paper, we discuss the boundedness of some well-known integral operators in space (L_(p_m),,a_m), which is a significant special case of Ba.     

A Class of Cone Sobolev Spaces on the Half-line

Meromorphic Mellin symbols arise in questions of characterizing elliptic regularity and the asymptotics of solutions to differential equations on spaces with conical singularities, and other singularities as well, and the construction of pseudodifferential parametrices to elliptic operators. Recently, various subalgebras of the algebra of all Mellin symbols arising in the cone or edge pseudodifferential calculus have been constructed. Therefore, our objective is to construct a cone pseudodiffe…     

On n-widths of some periodic convolution classes in Orlicz spaces

In this paper we extend the some accurate results on n-width of Sobolevclass W_∞~γ in L_p spaces to Orlicz spaces,and establish the correspondingresults for dual cases.     

On Mixed Pressure-Velocity Regularity Criteria to the Navier-stokes Equations in Lorentz Spaces,Part Ⅱ:The Non-slip Boundary Value Problem

This paper is a continuation of the authors recent work [Beir?o da Veiga, H.and Yang, J., On mixed pressure-velocity regularity criteria to the Navier-Stokes equations in Lorentz spaces, Chin. Ann. Math., 42(1), 2021, 1–16], in which mixed pressure-velocity criteria in Lorentz spaces for Leray-Hopf weak solutions of the three-dimensional NavierStokes equations, in the whole space R~3 and in the periodic torus T~3, are established. The purpose of the present work is to extend the result of mentio...     

Stability analysis of solutions to nonlinear stiff Volterra functional differential equations in Banach spaces

A series of stability, contractivity and asymptotic stability results of the solutions to nonlinear stiff Volterra functional differential equations (VFDEs) in Banach spaces is obtained, which provides the unified theoretical foundation for the stability analysis of solutions to nonlinear stiff problems in ordinary differential equations(ODEs), delay differential equations(DDEs), integro-differential equations(IDEs) and VFDEs of other type which appear in practice.     

Weighted Variation Inequalities for Singular Integrals and Commutators in Rearrangement Invariant Banach and Quasi-Banach Spaces

In order to study the boundedness of some operators in general function spaces which include Lorentz spaces and Orlicz spaces as special examples,Lorentz introduced a new space called rearrangement invariant Banach function spaces,denoted by RIBFS.It is shown in this paper that variation operators of singular integrals and their commutators are bounded on RIBFS whenever the kernels satisfy the L^r-H?rmander conditions.Moreover,we obtain some quantitative weighted bounds in the quasi-Ba...     

Smoothness and Differentiability of Orlicz Spaces

Smoothness and Differentiability of Orlicz spaces are of importance in applications of the approximation theory, the conditional expectation theory, probability limit theorems and the. nonlinear prediction theory as well as in other applications. They are discussed by Rao. M. M. in many parpers, but there     

Orlicz 空间小波展开的收敛性

In this paper we study the convergence in norm and pointwise convergence of wavelet expansion in the Orlicz spaces,and prove that,under certain conditions on the wavelet,the wavelet expansion converges in the Orlicz-norm and also converges almost everywhere.     

Asymptotic behaviour of solutions to the Navier-Stokes equations of a two-dimensional compressible flow

In this paper,we are concerned with the asymptotic behaviour of a weak solution to the Navier-Stokes equations for compressible barotropic flow in two space dimensions with the pressure function satisfying p(e) = a log d(e) for large .Here d > 2,a > 0.We introduce useful tools from the theory of Orlicz spaces and construct a suitable function which approximates the density for time going to infinity.Using properties of this function,we can prove the strong convergence of the density to its limit state.The behaviour of the velocity field and kinetic energy is also briefly discussed.