基于学习—遗忘效应的生产率降低损失索赔研究

建设工程项目很多具有重复性施工的特点,本文利用这种特点将学习-遗忘效应应用到平衡作业线(LOB)方法中,分析因为工程中断造成生产率的降低的现象,认为因生产率降低而导致工程工期的延长实际上超过工程实际中断的时间,最后以一个工程案例来说明分析过程.     

A counterexample on contractible transformations on graphs

Ivashchenko proposed the study of contractible transformations on graphs because of their applications to computer image analysis, theory of molecular spaces, and digital topology. He published five papers on this subject. Contractible transformations have recently been applied to topological data analysis. This paper presents a counterexample to several results that appeared in one of Ivashchenko’s works.     

Remark on the weierstrass points on curves

We give a treatment of the Weiertrass points of curves which is a little different from the treatment by Laksov. We introduce the notion of theith weight which makes the treatment easier and gives an algorithm for computing the gap sequence of an effective divisor and the weight at a point. Supported in part by NNSF of China.     

Remarks on contact relations on Boolean algebras

The paradigmatic example for a contact relation is that of having nondisjoint closures for regions in n-dimensional space. Generally, a contact relation is a binary relation on a Boolean algebra reflecting some of the properties of this example. We prove in this paper a topological and an algebraic representation theorem for contact algebras and solve two problems due to Düntsch and Winter and to Dimov and Vakarelov, respectively.     

Remarks on uniform bundles on projective spaces

On projective spaces of dimension \(d\ge 2\) defined over a field of positive characteristic we construct rank \(d+1\) uniform toric but non-homogeneous bundles, which do not exists in characteristic zero. These bundles are obtained by choosing suitable equivariant extensions of the Frobenius pullbacks of \(T_{\mathbb {P}^d}\) by a line bundle.     

A note on circle patterns on surfaces

In this paper we give two different proofs of Bobenko and Springborn’s theorem of circle pattern: there exists a hyperbolic (or Euclidean) circle pattern with proscribed intersection angles and cone angles on a cellular decomposed surface up to isometry (or similarity). This work is partially supported by NSF Grant #0625935.     

More on cancellative semigroups on manifolds

Communicated by D.R.Brown     

Some remarks on tautological sheaves on Hilbert schemes of points on a surface

We study tautological sheaves on the Hilbert scheme of points on a smooth quasi-projective algebraic surface by means of the Bridgeland–King–Reid transform. We obtain Brion–Danila’s Formulas for the derived direct image of tautological sheaves or their double tensor product for the Hilbert–Chow morphism; as an application we compute the cohomology of the Hilbert scheme with values in tautological sheaves or in their double tensor product, thus generalizing results previously obtained for tautological bundles.      

A note on pseudo-metrics on the plane

Every c-finite measure Μ on the set G of the lines on the plane such that $$(0){\text{ }}\mu {\text{(\{ g}} \in G:{\text{ }}P \in {\text{g\} ) = 0}}$$ for every point P?R ² generates a pseudo-metric F on the plane when one puts F P ₁, P ₂= \(\tfrac{1}{2}\) μ({g∈G:g separates the points P ₁ and P ₂}) The pseudo-metrics which are generated in this way possess the property of linear additivity, that is F(P ₁,P ₃)=F(P ₁,P ₂)+F(P ₂,P ₃) for P ₁,P ₂,P ₃ on a line, P ₂ between P ₁ and P ₃, and are continuous with respect to the Euclidean topology in R ² × R ². In this paper we prove the converse: every linear additive and continuous pseudo-metric F is generated as above by some c-finite measure Μ on G for which (0) holds. The method of proof shows that values of linearly additive and continuous pseudo-metric F inside every bounded convex polygon C are determined completely by the values of F on (δC)². The representation of pseudo-metrics by measures is useful in derivation of inequalities for the former.     

Remarks on continuum cardinals on Boolean algebras

We give some results concerning various generalized continuum cardinals. The results answer some natural questions which have arisen in preparing a new edition of 5 . To make the paper self‐contained we define all of the cardinal functions that enter into the theorems here. There are many problems concerning these new functions, and we formulate some of the more important ones.     

基于P-SVM的供应链企业可靠性预警研究

供应链企业可靠性是供应链可靠性的重要问题之一.在国内外研究文献综述基础上提出了供应链企业节点可靠性的初步预警指标.而后以此为基础,利用P-SVM方法完成了指标体系的构建及供应链企业可靠性预警.     

On certain conjectures on invariant measures on semigroups

A conjecture stating that a locally compact semigroup admits a twosided semi-invariant measure iff it contains a kernel which is a unimodular group, is proven. Also a conjecture stating that the support of an r^*-invariant measure is a left group, is proven under the condition that for some a ε F (=support of the measure), aF is right cancellative. Moreover four types of invariance for regular probability measures are shown to be equivalent. Also a new proof of the equivalence of a two-sided semi-invariant probability measure and the existence of a kernel which is a compact group, is given.     

基于传导变换的客户价值研究

以企业为价值感受主体、客户为价值感受客体的客户价值,衡量了客户对企业的相对重要性.首先基于传导变换理论,给出传导知识的定义,然后建立传导度以度量主动变换导致客户价值发生传导变换的效果,探讨了客户价值传导信息元集和传导知识的获取.研究可以为企业提供制定客户关系管理策略的依据,为客户价值研究提供新的思路.     

Remark on Gauss curvature equations on punctured disk

We give a new argument on the classification of solutions of Gauss curvature equation on R²; which was first proved by W. Chen and C. Li [Duke Math. J., 1991, 63(3): 615–622]. Our argument bases on the decomposition properties of the Gauss curvature equation on the punctured disk.     

Some problems on narrow operators on function spaces

It is known that if a rearrangement invariant (r.i.) space E on [0, 1] has an unconditional basis then every linear bounded operator on E is a sum of two narrow operators. On the other hand, for the classical space E = L ₁[0, 1] having no unconditional basis the sum of two narrow operators is a narrow operator. We show that a Köthe space on [0, 1] having “lots” of nonnarrow operators that are sum of two narrow operators need not have an unconditional basis. However, we do not know if such an r.i. space exists. Another result establishes sufficient conditions on an r.i. space E under which the orthogonal projection onto the closed linear span of the Rademacher system is a hereditarily narrow operator. This, in particular, answers a question of the first named author and Randrianantoanina (Problem 11.9 in [Popov M., Randrianantoanina B., Narrow Operators on Function Spaces and Vector Lattices, de Gruyter Stud. Math., 45, Walter de Gruyter, Berlin, 2013]).     

A note on geodesic foliations on the torus

We look at geodesic foliations on the Lorentzian 2-tori which are lightlike on a proper subset. We prove that they do not exist if the torus is geodesically complete. We describe some properties of their orthogonal foliations and we give several new examples.      

Remarks on curvature dimension conditions on graphs

We show a connection between the \(CDE'\) inequality introduced in Horn et al. (Volume doubling, Poincaré inequality and Gaussian heat kernel estimate for nonnegative curvature graphs. arXiv:1411.5087v2, 2014) and the \(CD\psi \) inequality established in Münch (Li–Yau inequality on finite graphs via non-linear curvature dimension conditions. arXiv:1412.3340v1, 2014). In particular, we introduce a \(CD_\psi ^\varphi \) inequality as a slight generalization of \(CD\psi \) which turns out to be equivalent to \(CDE'\) with appropriate choices of \(\varphi \) and \(\psi \). We use this to prove that the \(CDE'\) inequality implies the classical CD inequality on graphs, and that the \(CDE'\) inequality with curvature bound zero holds on Ricci-flat graphs.     

基于偏序集的PROMETHEE方法优化研究

尽管PROMETHEE是当前最受欢迎的多准则决策方法之一,但在实践应用过程中,模型的应用范围与质量依然受制于指标权重问题。一些常用的赋权方法,不仅没有解决不确定权重问题,反而增加了决策风险。在偏序集相关定理的基础上,给出权重的定性信息即权重次序,由流出矩阵、流入矩阵和净流矩阵等定义,得到了PROMETHEE的偏序集表达形式。当流入和流出之和为常数时,证明了模型存在对偶性质。根据对偶性质,简化了PROMETHEE方法的分析步骤,删减模型冗余信息。应用偏序集表示的PROMETHEE,突破了模型没有具体权重便无法应用的思维定势,解决了模型赋权困难,增强了模型的鲁棒性,拓展了模型处理数据类型的范围。