Extension of Hardy–Littlewood–Sobolev Inequalities for Riesz Potentials on Hypergroups

Mediterranean Journal of Mathematics - Let p be a prime number, let G be a finite group, let N be a normal subgroup of G, and let $$\theta $$ be a G-invariant irreducible character of N. In Rizo (J...     

环的广义斜导子

设R是一个半素环, RF(resp．Q)是它的左Martindale商环(对称Martindale 商环),K是R的一个本质理想,则K上的每一个广义斜导子μ能被唯一地扩展到RF和Q 上．设R是一个素环,K是R的一个本质理想,μ是K上的一个广义斜导子且α为其伴随自同构,d为其伴随斜导子,如果存在n≥0,使得对任意的x∈K都有μ(x)n=0,那么μ=0．     

Finite groups of even orders all of whose fourth maximal subgroups are weakly $$s_{2}$$ s 2 -permutable

Acta Mathematica Hungarica - Let p be a prime number. A positive integer m is said to be a $$p'$$ -number provided $$p\nmid m$$ . Let G be a finite group, and let H be a subgroup of G. We say...     

COARSE AND UNIFORM EMBEDDINGS INTO REFLEXIVE SPACES

Answering an old problem in nonlinear theory, we show that c₀cannot be coarsely or uniformly embedded into a reflexive Banachspace, but that any stable metric space can be coarsely anduniformly embedded into a reflexive space. We also show thatcertain quasi-reflexive spaces (such as the James space) alsocannot be coarsely embedded into a reflexive space and thatthe unit ball of these spaces cannot be uniformly embedded intoa reflexive space. We give a necessary condition for a metricspace to be coarsely or uniformly embeddable in a uniformlyconvex space.     

Zur Theorie der Integraltransformationen

Let A be a selfadjoint uniformly elliptic differential operator. Let the underlying domain be bounded. Eigenvalue problems can be solved then, and an arbitrary square integrable function may be developed in a Fourier series relative to the eigenfunctions. In general elliptic differential operators have a continuous spectrum, if the underlying domain is unbounded. In this case the spectral theorem provides a representation of a given function by an integral transformation. The spectral projector can be calculated, if the outgoing and incoming solutions are known (radiation condition). Thus integral transformations may be derived very easily. Four examples will be given: the Fourier sine transform, the Lebedev transform, the transformation belonging to the Dirichlet problem of the plate equation and, finally, the Fourier transformation.     

Nonlinear singular perturbation problems: Proofs of correctness of a formal approximation based on a contraction principle in a Banach space

For many singular perturbation problems formal approximations of the solution can be constructed. Here it will be shown that correctness of a formal approximation of sufficiently high order can be proven if (i) certain a priori estimates for the solution of the linearized problem can be obtained and (ii) the remainder term of linearization satisfies a certain smallness condition. The proof will be based on a contractive mapping in a Banach space. Applications are given for singularly perturbed nonlinear second-order elliptic problems with boundary conditions of Dirichlet type.     

一些同余问题的例外集合

利用特征和与指数和的估计,研究了一些同余问题的例外集合.具体来说,设p为充分大的素数,集合Y■Zp,正整数N相似文献   

弹性厚板的分区广义变分原理

本文提出弹性厚板分区广义变分原理,其要点如下:1.各分区可任意定为势能区或余能区.分区势能、分区余能、分区混合变分原理是它的三种特殊形式.2.每个分区中独立变分变量的个数可任意规定.每个分区可定为单类变量区、二类变量区或三类变量区.3.每个交界线上的位移和力的连接条件可以放宽.这个原理为非协调元的厚板有限元法提供理论基础.各种厚板有限元模型可看作这个原理的特殊应用.特别是弹性厚板分区混合变分原理的提出为分区混合有限元法应用于厚板问题打下了基础.     

A Generalised character theory for modules

Crawley-Boevey's concept of a character (a notion derived from Schofield's Sylvester rank functions) is extended so that characters with different image sets and classes may be analysed. A method of passing from these generalised characters to theories of modules is given and a converse technique is seen to be possible in certain cases. We consider in depth what happens when the character image is taken to be the ordinals with addition taken to be the Cantor sum. In particular we define a process whereby any Σ-pure-injective module satisfying a reasonable criterion can be assigned a unique ordinal character.     

图的（g，f）－因子和因子分解

设Ｇ是一个图，ｇ，ｆ是定义在图Ｇ的顶点集上的两个整数值函数且图Ｇ的一个（ｇ，ｆ）－因子是Ｇ的一个支撑子图Ｆ使对任意的ｘ∈Ｖ（Ｆ）有本文给出了一个图（ｇ，ｆ）－可因子化的若干充分条件和一个图是（ｇ，ｆ）－消去图的充分必要条件，并研究了这些条件的应用。     

The influence of X-semipermutability of subgroups on the structure of finite groups

Let A be a subgroup of a group G and X be a nonempty subset of G. A is said to be X-semipermutable in G if A has a supplement T in G such that A is X-permutable with every subgroup of T. In this paper, we investigate further the influence of X-semipermutability of some subgroups on the structure of finite groups. Some new criteria for a group G to be supersoluble or p-nilpotent are obtained.     

A new class of three-variable orthogonal polynomials and their recurrences relations

A new class of three-variable orthogonai polynomials,defined as eigenfunctions of a second order PDE operator,is studied.These polynomials are orthogonal over a curved tetrahedron region, which can be seen as a mapping from a traditional tetrahedron,and can be taken as an extension of the 2-D Steiner domain.The polynomials can be viewed as Jacobi polynomials on such a domain.Three- term relations are derived explicitly.The number of the individual terms,involved in the recurrences relations,are shown to be independent on the total degree of the polynomials.The numbers now are determined to be five and seven,with respect to two conjugate variables z,(?) and a real variable r, respectively.Three examples are discussed in details,which can be regarded as the analogues of the Chebyshev polynomials of the first and the second kinds,and Legendre polynomials.     

On Polynomial Functions over Finite Commutative Rings

Let R be an arbitrary finite commutative local ring. In this paper, we obtain a necessary and sufficient condition for a function over R to be a polynomial function. Before this paper, necessary and sufficient conditions for a function to be a polynomial function over some special finite commutative local rings were obtained.     

Analysis of pseudo-periodic chronological series with irregularly time-spaced data in view to their prediction. II. Fourier analysis

The problem originates from the necessity to predict luminosities of large-amplitude variable stars that are to be observed by the astronomical satellite HIPPARCOS. The data have a specific character: they are unequally time-spaced and can be missing during a long time in comparison to the pseudo-period. So the classical method of time-series analysis must be adapted and new methods are to be searched. In this paper we present a numerical solution derived from a Fourier analysis.     

图的（g，f）－因子和因子分解

设Ｇ是一个图，ｇ，ｆ是定义在图Ｇ的顶点集上的两个整数值函数且图Ｇ的一个（ｇ，ｆ）－因子是Ｇ的一个支撑子图Ｆ使对任意的ｘ∈Ｖ（Ｆ）有本文给出了一个图（ｇ，ｆ）－可因子化的若干充分条件和一个图是（ｇ，ｆ）－消去图的充分必要条件，并研究了这些条件的应用。     

Algorithms for part and machine selection in flexible manufacturing systems

Deciding whether FMS technology is viable for a given application, and if so, what machines should comprise the FMS and what parts should be produced on it, can be a difficult task. Manual methods suffice only for situations where a small number of FMS-type machines are to be considered and less than a few dozen candidate parts are to be chosen from. When both machines and parts are to be selected from a larger number of candidates, manual methods become cumbersome and time consuming, and computer-based decision aids become a necessity. This paper gives an overview of the required decision process, and then focuses on those stages for which computer-based decision aids can be used effectively. Particular decision aids are described, and case studies are cited to illustrate their motivation and use.     

Some bounds for the annihilators of local cohomology and Ext modules

Czechoslovak Mathematical Journal - Let $$\mathfrak{a}$$ be an ideal of a commutative Noetherian ring R and t be a nonnegative integer. Let M and N be two finitely generated R-modules. In certain...     

Lifting Property of Direct Sums of Hollow Modules

We give necessary and sufficient conditions for a module M with a decomposition that complements maximal direct summands to be a lifting module. We apply our results to get a necessary and sufficient condition for a direct sum of modules to be a quasi-discrete (discrete) module. We also give some sufficient conditions for a lifting module to be a direct sum of indecomposables.     

关于内射维数有限的cotilting余模

令K是域,设C是一个K-余代数,T为cotilting左C-余模,通过对cotilting余模的性质和理论的研究,得到关于cotilting余模的一些有意义的结果.     

群分次环和Morita等价

设Ｒ是Ｇ－分次环，Ｈ是Ｇ的子群，本文通过构造两个Ｍｏｒｉｔａｃｏｎｔｅｘｔ，给出了环Ｂ｛Ｈ｝Ｍｏｒｉｔａ等价于Ｒ＿Ｈ，Ｒ＃Ｇ￣＊Ｍｏｒｉｔａ等价于Ｒ＿Ｈ＃Ｈ￣＊的充分必要条件．