2—距离空间中三个等价的不动点定理

自Gahler于1963年引入2-距离空间理论以来,国内外一些学者研究了该空间上的不动点定理,这方面的成果在[2]中作了系统的介绍。本文首先给出2-距离空间中一个压缩型映象的不动点定理,并由它导出另两个不动点定理。这两个定理分别是通常距离空间中D.W.Boyd and J.S.Wong不动点定理和J.Dugundji and A.Granas不动点定理的推广。最后,我们还证明上述三个不动点定理的等价性。     

一类捕食者-食饵系统的全局结构

本文中我们证明了关于一般捕食者-食饵系统不存在闭轨线的定理,即文中定理2.应用这一定理和关于捕食者-食饵系统极限环的存在唯一性定理[1],我们完成了在各种参数条件对一个具体的捕食者-食饵系统模型[2]的研究.     

择一定理的推广

众所周知,择一定理是推导数学规划解的性质和最优性条件的主要工具.因此,讨论数学规划的一个重要途径就是推广择一定理,使它有更广泛的实用性.文献[1-3]就择一定理作过推广并就推广后的择一定理讨论了许多应用.文献[4-5]就[2-3]中给出的择一定理在多日标规划和向量极值问题上又找到了许多应用.在这篇文章里,我们提出广义次似凸映射概念,它是对[2-3]中次似凸映射的真     

型Aω~2-半群（英文）

研究了具有真*-核的满足条件D*=D的型Aω~2-半群,获得了它的结构定理.并且获得了这类半群的同构定理.     

单侧导数和对称导数混合方式下的微分中值定理

微分中值定理是分析中的一个重要定理,文[1-2]用对称导数讨论该定理,文[3-4]用单侧导数讨论该定理,而本文把两种导数结合起来以混合方式给出该定理的三种形式,且条件更弱.     

关于向量优化问题的Δ函数标量化刻画的某些注记

近期,夏远梅等(重庆师范大学（自然科学版）,2015,32(1):12-15)利用Δ函数通过非线性标量化方法研究了向量优化问题的?-真有效解并举例说明了主要结果.笔者指出:其定理1是Gao等(Journal of Industrial and Management Optimization,2011,7（2）: 483-496)建立的定理4.6(i)的特例;其定理2的证明存在不足.通过研究一般的(C,ε)-真有效解的Δ函数非线性标量化,给出了定理2的严谨证明.最后,在?-真有效解存在的情况下举例说明了主要结果.     

运用韦达定理五注意

<正>韦达定理是初中代数的重要定理,应用十分广泛,韦达定理有用但需会用.运用韦达定理除确切掌握定理外,还必须注意以下五个细节问题.一、注意根的符号例1已知α、β是方程x2+5x+2=0的两根,求(α/β)1/2+(β/α)1/2的值.解由韦达定理,知α+β=-5,αβ=2,     

与线性变换的完全环同构的环理论(Ⅳ)

<正> 基座概念对本原环的结构研究起着十分重要作用.为了对本原环的结构作进一步研究,我们引进俨基座概念.通常基座概念就是我们特殊情形的o-基座概念.利用ν-基座概念,我们建立了ν-结构定理。通常本原环结构定理(见[2]p.75)是ν-结构定理的一种特殊情况. 为了引进ν-基座,我们改变一下本原环的基座定义,使它具有能表达ν-基座的一般形式的特点且能建立所要求的ν-结构定理.为此我们来提一下§2中所获得的结果:     

以较低截断重数分担超平面的亚纯映射的唯一性问题

首先证明了一些以较低截断重数分担2n+2个超平面的亚纯映射的唯一性定理.最后一章给出了在条件f~(-1)(H_j)■g~(-1)(H_j)及q≥2n+3下的一个唯一性定理的简单证明.     

一个临界点定理和应用

<正> 本文的目的是体现临界点定理和映象度理论的结合.利用 Leray-Schauder 映象度,本文把 A.Castro 的临界点定理([3],[4])作了推广,该定理是本文定理1中映象度=(-1)~k 的特殊情况.定理2是定理1的一个应用.作为定理2的应用,我们举出常微分方程两点边值问题解的存在性的例子.以前的结果(例如[1—4])不能证明这问题解的存在性.     

Integrating design problems in mathematics curriculum: an architecture college case study

This paper reports an attempt to improve results in the mathematics course in one of the architecture colleges in Israel through practise in applications. The effect of integrating structure design problems in the calculus curriculum on students' achievements and attitudes was examined. The applied topics in the curriculum were connected to calculus topics and studied through problembased learning activities. The integrated curriculum was implemented and the learning results in experimental and control groups were assessed by means of achievement tests, attitude questionnaires and student interviews. The learning achievements in the experimental group proved to be significantly higher than in the control group. The positive impact of learning applications on motivation, understanding, creativity and interest in mathematics is indicated.     

角蛋白16和17在部分表皮肿瘤中的表达和意义

目的 研究角蛋白16 和17（K16、K17）在部分表皮肿瘤中的表达和意义。方法 采用免疫组化法检测K16、K17在正常皮肤、脂溢性角化病、日光性角化病、皮角、基底细胞癌、鳞状细胞癌中的表达。结果 K16、K17 在正常皮肤表皮各层呈阴性表达;在脂溢性角化病表皮各层中除了角质层外大多呈阳性表达;在日光性角化病表皮K16 均不表达,K17 除了角质层外在其他各层也不表达;K16 在皮角表皮棘层呈强阳性表达,但在其他各层均呈阴性表达,K17 在皮角表皮各层基本呈阳性或强阳性表达;在基底细胞癌中,K16、K17除了在棘层呈弱阳性表达外,在其他各层均呈阴性表达;在鳞状细胞癌中,K16 在基底层呈阴性表达,但在其他各层及K17 在表皮全层均呈阳性或强阳性表达。K16 除基底层外在肿瘤表皮其他各层表达比较差异均有统计学意义（均P＜0.05）;K17 在表皮各层表达差异均有统计学意义（均P＜0.05）。结论 K16、K17的表达状况可为表皮肿瘤的鉴别诊断提供病理学方面的依据。     

Preface

We are presenting in this volume the collection of extended abstracts of 66 talks that were presented at Combinatorics 2012 in Perugia, Italy. Combinatorics 2012 is the 17th in the series of combinatorics conferences held in Italy, first in 1981, next in 1982 and every two years since then.     

我国制造业背景下质量管理活动的量表开发研究

质量管理的测度是质量管理实证研究的基础,但我国在此领域还处于起步阶段。以重庆市制造业企业为样本,采用基于偏最小二乘法的证实性因子分析方法,对我国制造业企业的质量管理活动进行了实证度量。结论显示,我国制造业企业质量管理活动包含六个方面的主要内容:企业高层的支持、员工的参与、供应商关系、重视客户、产品设计和流程管理。研究给出了具体的我国质量管理活动的测度量表。     

Conceptualizations of slope in Mexican intended curriculum

Slope is a fundamental mathematics concept in middle and high school that transcends to the university level. An understanding of slope is needed at the university level since slope plays an important role in understanding problems involving variation and change. In this study Mexican curricula documents were examined to determine which conceptualizations of slope are addressed in the intended mathematics curriculum. To explain the results, we use conceptualizations of slope identified in previous research. Our findings reveal that, to a certain extent, the conceptualizations proposed in the Mexican intended mathematics curriculum differ slightly in terms of the emphasis and timing of instruction from what others have identified in the U.S., with slope as a geometric ratio receiving less emphasis in the Mexican curriculum. There was also noted discontinuity within the Mexican curriculum in introducing slope in grade 9 and subsequently introducing of linear functions in grade 10 without explicit mention of slope. Suggestions are made for future studies, both to consider the conceptualizations of slope promoted in the Mexican textbooks and the impact they have in classroom instruction and student learning of slope.     

Rawlsian altruism with perfect discrimination leads to social efficiency

Recent studies draw attention on the highly specialized capacity of human beings in recognizing altruists versus cheaters in social interactions. These results hint at the existence of specialized abilities that support discriminating behavior in strategic interactions. In this paper, we explore the implications of discriminating behavior in the study of the indirect evolutionary selection of selfish versus altruistic motivations in the context of generic 2×2 base games, and in particular for coordination and cooperation scenarios. We find that inequality averse (Rawlsian) altruism can enforce under rather general conditions socially optimal outcomes, including cases where selfishness cannot, such as in prisoner’s dilemmas. Inequality seeking (Nietzschian) altruism in no case improves upon Rawlsian altruism in terms of social optimality of outcomes, and often does worse. In the cooperation scenario in particular, Nietzschean altruism never manages to implement the cooperative outcome. Under perfect discrimination, moreover, inequality averse (Rawlsian) altruism often evolves at the expense of selfishness. These results suggest that the development of sophisticated discrimination abilities may be strongly adaptive in supporting fairness-oriented forms of pro-sociality in humans in the context of social dilemmas and coordination problems.     

Robust heteroclinic cycles

Summary One phenomenon in the dynamics of differential equations which does not typically occur in systems without symmetry is heteroclinic cycles. In symmetric systems, cycles can be robust for symmetry-preserving perturbations and stable. Cycles have been observed in a number of simulations and experiments, for example in rotating convection between two plates and for turbulent flows in a boundary layer. Theoretically the existence of robust cycles has been proved in the unfoldings of some low codimension bifurcations and in the context of forced symmetry breaking from a larger to a smaller symmetry group. In this article we review the theoretical and the applied research on robust cycles.     

Academics’ perceptions of the use and relevance of software in quantitative and financial disciplines

Software may be used in university teaching both to enhance student learning of discipline-content knowledge and skills, and to equip students with capabilities that will be useful in their future careers. Although research has indicated that software may be used as an effective way of engaging students and enhancing learning in certain scenarios, relatively little is known about academic practices with regard to the use of software more generally or about the extent to which this software is subsequently used by graduates in the workplace. This article reports on the results of a survey of academics in quantitative and financial disciplines, which is part of a broader study also encompassing recent graduates and employers. Results indicate that a variety of software packages are in widespread use in university programmes in quantitative and financial disciplines. Most surveyed academics believe that the use of software enhances learning and enables students to solve otherwise intractable problems. A majority also rate spreadsheet skills in particular as very important for the employability of graduates. A better understanding of the use of software in university teaching points the way to how curricula can be revised to enhance learning and prepare graduates for professional work.     

An overview on the history of actuarial calculus in Portugal until the late 19th century

Pension funds, namely survivors' pension funds were established in Portugal in the late 18th century, in mutual benefit societies. The first Portuguese life assurance companies were created in the first half of the 19th century but their activity was not very extensive. Only in the 20th century did both institutions become actuarially-based. In this paper, we provide an overview of the development of actuarial calculus in Portugal until the late 19th century, in order to contextualise the scientific progress of those institutions, mainly the former. This paper lays the groundwork for further research on the history of actuarial calculus in Portugal.     

Modelling,making inferences and making decisions: The roles of sensitivity analysis

Sensitivity analysis, robustness studies and uncertainty analyses are key stages in the modelling, inference and evaluation used in operational research, decision analytic and risk management studies. However, sensitivity methods -or others so similar technically that they are difficult to distinguish from sensitivity methods- are used in many different circumstances for many different purposes; and the manner of their use in one context may be inappropriate in another. Thus in this paper, I categorise and explore the use of sensitivity analysis and its parallels, and in doing so I hope to provide a guide and typology to a large growing literature.