非紧Riemman流形上的一类Kazdan-Warner型方程

讨论一类非紧Riemman流形上的Kazdan-Warner型方程. 作为应用, 在一类非紧Kähler流形上得到了关于全纯线丛的Hermitian-Yang-Mills-Higgs度量的存在性定理.     

关于Hopf丛S3的几个论题

本文证明了Hopf主纤维丛S^3的几个相关的命题，指出底流形S^3上的Laplace算子在主丛上的提升是主丛S^3上的Laplace算子，以及主丛的嵌入截面具有不动点性质等。     

群分次λ-HOPF代数的一些构造

研究群分次λ-双代数(Hopf代数)的一些构造,利用给定的群分次λ-双代数(Hopf代数)和群上的双特征标得到两类新的群分次λ-双代数(Hopf代数).     

带弱内射的Hopf代数结构

利用已知Hopf代数构造新的Hopf代数是Hopf代数理论中最基本的问题之一．该文给出了Smash积A#H为Hopf代数，H是A#H的商Hopf代数， 且具有弱内射H→A#H的充分必要条件．易证，此种构造推广了Radford和Majid等人所构造的双积和双交叉积等结构．     

置换群S_6上的一类Hopf代数结构

本文研究了置换群S_6上的分次Hopf代数的构造问题.利用箭向,建立了群的带特征标的分歧系统和分次Hopf代数之间的联系,获得了群S_6的特征标和S_6的自同构群Aut(S_6)之间的关系.从而构造出了就S_6的某个分歧数据的不同构的所有分次Hopf代数.     

偏π-余模的Maschke型定理

本文研究了偏群余模的Mashcke型定理.利用弱Hopf群余代数推广Hopf代数的方法,获得了偏群余模的Mashcke型定理.推广了Hopf代数理论中的Maschke型定理和[8]的相关结论.     

一类混合比率依赖食物链扩散模型的Hopf分支

研究了一类基于混合比率依赖的三种群食物链扩散模型.利用Hurwitz判据讨论了非负常数平衡解的稳定性,并通过理论分析研究了该系统空间齐次和空间非齐次的Hopf分支,同时利用规范型理论和中心流形定理给出Hopf分支方向和分支周期解稳定性的判据.最后借助Matlab软件进行数值模拟,验证补充理论分析结果.     

偏π-余模的Maschke型定理（英文）

本文研究了偏群余模的Mashcke型定理.利用弱Hopf群余代数推广Hopf代数的方法,获得了偏群余模的Mashcke型定理.推广了Hopf代数理论中的Maschke型定理和[8]的相关结论.     

弱Hopf量子Yang-Baxter H-模基本定理(英文)

本文引入弱Hopf量子Yang-Baxter模概念.利用弱Hopf模基本定理的方法,获得了弱Hopf量子Yang-Baxter模基本定理,进一步还得到了相关Hopf模基本定理.     

相配群胚上的诱导联络

本文引入了相配群胚和相配主丛的概念,它们是一对具有相同传递函数的局部平凡李群胚（Г→_→P,α,β）和主丛（B,P,π,G）.我们首先考察了相配群胚Г的内子群胚GГ的局部平凡化,利用这个局部平凡化证明了在B和GГ之间自然存在着一个丛同构.通过这个丛同构以及B的联络日逐步得到了H在GГ和Г上的诱导联络,进而定义了Г上分别以α,β为投影的左联络和右联络,这两个联络都是在Г上整体有定义的,与以往李群胚上的联络只是定义在李代数胚上不同.     

Estimation of the number of components of finite mixtures of multivariate distributions

An estimator of the number of components of a finite mixture ofk-dimensional distributions is given on the basis of a one-dimensional independent random sample obtained by a transformation of ak-dimensional independent random sample. A consistency of the estimator is shown. Some simulation results are given in a case of finite mixtures of two-dimensional normal distributions.     

Eigenvector p-Bases of Rings of Constants of Derivations

Let A be a UFD of characteristic p > 0, let 𝒵 be a set of some eigenvectors of a derivation of A. We prove, under some additional assumptions, a necessary and sufficient condition for 𝒵 to be a p-basis of the minimal ring of constants containing 𝒵. The main preparatory result is the unique decomposition theorem with respect to a factor from a given subalgebra containing A^p.     

Galois Structure of K-Groups of Rings of Integers

N/Kbe a Galois extension of number fields with finite Galois group G.We describe a new approach for constructing invariants of the G-module structure of the K groups of the ring of integers of N in the Grothendieck group of finitely generated projective Z[G]modules. In various cases we can relate these classes, and their function field counterparts, to the root number class of Fröhlich and Cassou-Noguès.     

有资格限制的指派问题的求解方法

在实际的指派工作中，常会遇到某个人有没有资格去承担某项工作的问题，因此，本建立了有资格限制的指派问题的数学模型。在此数学模型中，将效益矩阵转化为判定矩阵，由此给出了判定此种指派问题是否有解的方法；在有解的情况下，进一步将效益矩阵转化为求解矩阵，从而将有资格限制的指派问题化为传统的指派问题来求解。最后给出了一个数值例子来说明这样的处理方法是有效的。     

On Sums of Coefficients of Products of Polynomials

We study the nilpotency of the sums of all coefficients of some sorts of products of polynomials over reversible, IFP, and NI rings, and introduce an SCN ring as a generalization. We characterize SCN rings in relation with related ring properties, and also provide several useful properties and ring extensions of SCN rings.     

Convergence of sequences of sets of associated primes

It is a well-known result of M. Brodmann that if is an ideal of a commutative Noetherian ring , then the set of associated primes of the -th power of is constant for all large . This paper is concerned with the following question: given a prime ideal of which is known to be in for all large integers , can one identify a term of the sequence beyond which will subsequently be an ever-present? This paper presents some results about convergence of sequences of sets of associated primes of graded components of finitely generated graded modules over a standard positively graded commutative Noetherian ring; those results are then applied to the above question.

     

Rates of Convergence of Means of Euclidean Functionals

Let L be the Euclidean functional with p-th power-weighted edges. Examples include the sum of the p-th power-weighted lengths of the edges in minimal spanning trees, traveling salesman tours, and minimal matchings. Motivated by the works of Steele, Redmond and Yukich (Ann. Appl. Probab. 4, 1057–1073, 1994, Stoch. Process. Appl. 61, 289–304, 1996) have shown that for n i.i.d. sample points {X ₁,…,X _n } from [0,1] ^d , L({X ₁,…,X _n })/n ^(d−p)/d converges a.s. to a finite constant. Here we bound the rate of convergence of EL({X ₁,…,X _n })/n ^(d−p)/d . Y. Koo supported by the BK21 project of the Department of Mathematics, Sungkyunkwan University. S. Lee supported by the BK21 project of the Department of Mathematics, Yonsei University.     

Number of connected components of groups of real points of adjoint groups

We present a unified approach to compute the number of connected components in the group of real points of adjoint almost simple real algebraic groups.     

Enumeration of perfect matchings of a type of Cartesian products of graphs

Let G be a graph and let Pm(G) denote the number of perfect matchings of G.We denote the path with m vertices by P_m and the Cartesian product of graphs G and H by G×H. In this paper, as the continuance of our paper [W. Yan, F. Zhang, Enumeration of perfect matchings of graphs with reflective symmetry by Pfaffians, Adv. Appl. Math. 32 (2004) 175-188], we enumerate perfect matchings in a type of Cartesian products of graphs by the Pfaffian method, which was discovered by Kasteleyn. Here are some of our results:1. Let T be a tree and let C_n denote the cycle with n vertices. Then Pm(C₄×T)=∏(2+α²), where the product ranges over all eigenvalues α of T. Moreover, we prove that Pm(C₄×T) is always a square or double a square.2. Let T be a tree. Then Pm(P₄×T)=∏(1+3α²+α⁴), where the product ranges over all non-negative eigenvalues α of T.3. Let T be a tree with a perfect matching. Then Pm(P₃×T)=∏(2+α²), where the product ranges over all positive eigenvalues α of T. Moreover, we prove that Pm(C₄×T)=[Pm(P₃×T)]².