Nonnegative Matrix Factorization based on the Geometry of Positive Numbers

We consider the problem of nonnegative matrix factorization where the typical objective function is altered based on geometrical arguments. A noneuclidean geometry on positive real numbers is used to describe the nonnegative entries of a nonnegative matrix, influencing the factorization model. We design an optimization procedure from a differential geometric point of view for the newly proposed model. (© 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

A Survey on the Differential and Symplectic Geometry of Linking Numbers

The aim of the present survey mainly consists in illustrating some recently emerged differential and symplectic geometric aspects of the ordinary and higher order linking numbers of knot theory, within the modern geometrical and topological framework, constantly referring to their multifaceted physical origins and interpretations. Lecture held in the Seminario Matematico e Fisico on May 2, 2005 Received: May 2006     

Fibonacci Numbers and an Area Puzzle: Connecting Geometry and Algebra in the Mathematics Classroom

A mathematical puzzle that asks about “missing” area leads to an exploration of the Fibonacci sequence as well as genuine inquiry in plane geometry connected to algebra. This article discusses the inquiry, the concepts, the solution, and an extension that deepens all students’ understanding of connections between algebra and geometry.     

Mersenne数$M_p$都是孤立数

设p是素数,M_P=2~P-1.本文证明了M_P都是孤立数.     

On Periodic Expansions of Pisot Numbers and Salem Numbers

Let ß > 1 be a real number, and let T_ßbe the associated ß-transformation of the unit interval[0,1) given by T_ß = ß (mod 1). We writeQ for the set of rational numbers, Q (ß) for the smallestsub-field of the reals containing ß, and Per (ß)for the set of (eventually) periodic points for T_ß,i.e. for the set of points whose orbits under T_ß,are finite. In this note we prove the following results: (1) If Q [0,1) Per (ß), then ß is eithera Pisot- or a Salem-number. (2) If ß is a Pisot-number, then Per (ß)= Q(ß) [0,1). The last section contains explicit formulae for the cardinalitiesof the sets {T^k_ß: k 0}, Q [0, 1), if ßsatisfies an equation ß² = nß + 1 with n 1. Present address: Mathematics Institute, University of Warwick,Coventry CV4 7AL.     

三参数区间数的联系数在招标评价中的应用

在联系数理论的基础上,针对评标中某些权重不宜用定值表示的问题,采用三参数区间数表示,并转化为联系数以表示权重,结合综合评价方法建立多指标评价模型来解决多属性决策问题,在招标决策中体现出方法的简易、有效.     

Steiner Numbers in Graphs

Abstract

The Steiner distance d(S) of a set S of vertices in a connected graph G is the minimum size of a connected subgraph of G that contains S. The Steiner number s(G) of a connected graph G of order p is the smallest positive integer m for which there exists a set S of m vertices of G such that d(S) = p—1. A smallest set S of vertices of a connected graph G of order p for which d(S) = p—1 is called a Steiner spanning set of G. It is shown that every connected graph has a unique Steiner spanning set. If G is a connected graph of order p and k is an integer with 0 ≤ k ≤ p—1, then the kth Steiner number sk(G) of G is the smallest positive integer m for which there exists a set S of m vertices of G such that d(S) = k. The sequence s_o(G),s₁ (G),…,8_p-1(G) is called the Steiner sequence of G. Steiner sequences for trees are characterized.     

Euler数和高阶Euler数的推广

The purpose of this paper is to define the generalized Euler numbers and the generalized Euler numbers of higher order, their recursion formula and some properties were established, accordingly Euler numbers and Euler numbers of higher order were extended.     

Riemann-Finsler Geometry with Applications to Information Geometry

Information geometry is a new branch in mathematics, originated from the applications of differential geometry to statistics. In this paper we briefly introduce Riemann-Finsler geometry, by which we establish Information Geometry on a much broader base, so that the potential applications of Information Geometry will be beyond statistics.     

一种基于模糊数中心的模糊数排序方法

模糊数的排序法在决策及其它模糊应用系统的研究中起着非常重要的作用，众多学者提出了很多模糊数的排序方法，Cheng和Chu提出两种与模糊数中心有关的排序指标。但这两种方法都有明显的缺陷。本文构造了新的排序指标，能有效地实现各种模糊数的排序，最后用实例与前两种排序指标进行比较，体现出新指标的优越性。     

Ternary Numbers, Algebras of Reflexive Numbers and Berger Graphs

The Calabi-Yau spaces with SU(n) holonomy can be studied by the algebraic way through the integer lattice where one can construct the Newton reflexive polyhedra or the Berger graphs. Our conjecture is that the Berger graphs can be directly related with the n-ary algebras. To find such algebras we study the n-ary generalization of the well-known binary norm division algebras, , which helped to discover the most important “minimal” binary simple Lie groups, U(1), SU(2) and G(2). As the most important example, we consider the case n = 3, which gives the ternary generalization of quaternions (octonions), 3 ⁿ , n = 2, 3, respectively. The ternary generalization of quaternions is directly related to the new ternary algebra (group) which are related to the natural extensions of the binary su(3) algebra (SU(3) group). Using this ternary algebra we found the solution for the Berger graph: a tetrahedron.

“Why geniosis live so short? They wanna stay kids.”

Alexey Dubrovski: On leave from JINR, Russia. Guennadi Volkov: On leave from PNPI, Russia.     

Catenarian Numbers

An integer n is called catenarian if, whenever L/K is an n-dimensional field extension, all maximal chains of fields going from K to L have the same length. Catenarian field extensions and catenarian groups are defined analogously. If n is an even positive integer, 6n is non-catenarian. If n ≥ 3 is odd, there exist infinitely many odd primes p such that p ² n is non-catenarian. A finite-dimensional field extension is catenarian iff its maximal separable subextension is. If q < p are odd primes where q divides p ? 1 (resp., q divides p + 1), every (resp., not every) group of order p ² q is catenarian.     

Derandomization in Computational Geometry

We survey techniques for replacing randomized algorithms in computational geometry by deterministic ones with a similar asymptotic running time.