On Some Linear Maps from an Algebra into Its Bimodules

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正则Fuzzy蕴涵代数

Fuzzy蕴涵代数是 [0 ,1]值逻辑的蕴涵联结词的一种代数抽象。本文给出正则 Fuzzy蕴涵代数的几个刻画 ,并且得到正则 Fuzzy蕴涵代数构成格的几个条件。     

德摩根拓扑代数可度量化的一个充分条件

得出德摩根拓扑代数可度量化的一个充分条件 ,其结果将经典 Urysohn度量化定理以及模糊度量化定理作为其特例     

完全分配格上的Urysohn分离性

在无逆序对合对应的完全分配格上建立Urysohn分离公理，该公理一定推得Hausdorff分离公理^[1]且具有遗传性。此外，通过引入滤及网的L—Urysohn收敛理论，得到Urysohn分离性的滤式及网式刻画。     

Revival of a classical topic in differential geometry: the exploration of envelopes in a computerized environment

Learning mathematics in a technology-rich environment enables us to revive classical topics which have been removed from the curriculum a long time ago. Both theoretical issues and applications can be studied with an experimental process. We present how envelopes of 1-parameter families of plane curves and some of their applications can be presented early in the curriculum either for pre-service teachers or for in-service teachers. This approach may be useful for students in an engineering curriculum. Working with technology yields important effects, such as reviving classical topics, broadening perspectives on already known topics, and enhancing the learner's experimental skills, where conversion between various registers of representation is an important issue.     

什么是几何控制论?(上)

介绍了几何控制的若干基本概念和理论,并以蛇板的可控性为例展示了几何控制理论的魅力和实用性。     

CR-Admissible $$\mathbb{{Z}}_{2}$$-gradations and CR-symmetries

Complementing the results of (Lotta and Nacinovich, Adv. Math. 191(1): 114–146, 2005), we show that the minimal orbit M of a real form G of a semisimple complex Lie group in a flag manifold is CR-symmetric (see (Kaup and Zaitsev Adv. Math. 149(2):145–181, 2000)) if and only if the corresponding CR algebra admits a gradation compatible with the CR structure.      

The full power of the half-power

We use the complex square root to define a very simple homotopic invariant over the non-vanishing functions defined on the circle. As a consequence we provide easy proofs of the plane Brouwer fixed point theorem and the Fundamental Theorem of Algebra. The relation of this new invariant with the winding number and the Brouwer degree will be fully unveiled.     

Hidden lessons: How a focus on slope-like properties of quadratic functions encouraged unexpected generalizations

This article presents secondary students’ generalizations about the connections between algebraic and graphical representations of quadratic functions, focusing specifically on the roles of the parameters a, b, and c in the general form of a quadratic function, y = ax² + bx + c. Students’ generalizations about these connections led to a surprising finding: two-thirds of the students interviewed identified the parameter a as the “slope” of the parabola. Analysis of qualitative data from interviews and classroom observations led to the development of three focusing phenomena in the classroom environment that inadvertently supported a focus on slope-like properties of quadratic functions: (a) the use of linear analogies, (b) the rise over run method, and (c) viewing a as dynamic rather than static.