极大前缀码的一些刻划

设X~*是字母表X上的自由幺半群,以X~*为顶点集构造一个语言图Г(X~*),引入语言图Г(X~*)的横截集的概念,给出了极大前缀码的一些刻划.     

Kraft不等式的改进

首次引入前缀码的拟特征和序列的概念,给出了前缀码为极大前缀码的一些刻划,并对著名的Kraft不等式作了改进.     

一般化凸空间上的截口定理和变分不等式定理

摘要：本文利用Brouwer不动点定理或已知的KKM型定理，得到一般化凸空间上的截口定理．讨论了变分不等式解的存在性问题。对文中的相应结论进行了一般化和改进。     

Sequential Determination of the {1, 4}-Inverse of a Matrix

In this paper, we provide a set of results for the sequential determination of the {1, 4}-generalized inverse of a matrix. This inverse is of importance in areas where the minimal norm solution of a system of algebraic equations is desired.     

三矩阵乘积的(T,S,2)-逆的反序律

矩阵A的(T,S,2)-逆是指适合XAX=X,R(X)=T和N(X)=S的矩阵X,以矩阵的秩为工具,本文研究了三矩阵乘积的(T,S,2)-逆的反序律,给出了(ABC)_(T4,S4)⁽²⁾=C_(T3,S3)⁽²⁾B_(T2,S2)⁽²⁾A_(T1,S1)⁽²⁾的充要条件。     

Non-periodic finite-element formulation of orbital-free density functional theory

We propose an approach to perform orbital-free density functional theory calculations in a non-periodic setting using the finite-element method. We consider this a step towards constructing a seamless multi-scale approach for studying defects like vacancies, dislocations and cracks that require quantum mechanical resolution at the core and are sensitive to long range continuum stresses. In this paper, we describe a local real-space variational formulation for orbital-free density functional theory, including the electrostatic terms and prove existence results. We prove the convergence of the finite-element approximation including numerical quadratures for our variational formulation. Finally, we demonstrate our method using examples.     

Recursive Formulas for the Generalized LM-Inverse of a Matrix

In this paper, we present recursive formulas for the sequential determination of the generalized LM-inverse of a general matrix. The formulas are developed for a matrix augmented by a column. These formulas are particularized to obtain also recursive relations for the generalized L-inverse of a general matrix augmented by a column.     

Avoiding σ-porous sets in Hilbert spaces

We give a constructive proof that any σ  -porous subset of a Hilbert space has Lebesgue measure zero on typical C¹$C^1$ curves. Further, we discover that this result does not extend to all forms of porosity; we find that even power-p   porous sets may meet many C¹$C^1$ curves in positive measure.     

Derivation of a contact law between a free fluid and thin porous layers via asymptotic analysis methods

We describe the asymptotic behaviour of an incompressible viscous free fluid in contact with a porous layer flow through the porous layer surface. This porous layer has a small thickness and consists of thin channels periodically distributed. Two scales are present in this porous medium, one associated to the periodicity of the distribution of the channels and the other to the size of these channels. Proving estimates on the solution of this Stokes problem, we establish a critical link between these two scales. We prove that the limit problem is a Stokes flow in the free domain with further boundary conditions on the basis of the domain which involve an extra velocity, an extra pressure and two second-order tensors. This limit problem is obtained using Γ-convergence methods. We finally consider the case of a Navier–Stokes flow within this context.     

Study on the Structure of Γ-Semihypergroups

In this article, we study Γ-semihypergroups introduced recently. We introduce the hyper versions of Green's relations in Γ-semihypergroups and give some related characterizations. We introduce the n-prime Γ-hyperideal and n-semiprime Γ-hyperideal of a Γ-semihypergroup and show that for any integer n ≥ 2, n-prime Γ-hyperideals are a generalization of prime Γ-ideals. We also give the relationship between n-prime Γ-hyperideals and Γ-hyperideal extensions in Γ-semihypergroups. Then, we deal with prime ideal and introduce the notion of prime radical in a Γ-semihypergroup M, and also, we obtain some results and relations among the prime radicals of M and S, where S is the left operator semihypergroup of M.