Search results for "algebra"

On the History of Differentiable Manifolds

2012

International audience; We discuss central aspects of history of the concept of an affine dif-ferentiable manifold, as a proposal confirming the need for using some quantitative methods (drawn from elementary Model Theory) in Mathematical Historiography. In particular, we prove that this geometric structure is a syntactic rigid designator in the sense of Kripke-Putnam.

A Series of Hadamard Designs with Large Automorphism Groups

2000

Abstract Whilst studying a certain symmetric (99, 49, 24)-design acted upon by a Frobenius group of order 21, it became clear that the design would be a member of an infinite series of symmetric (2q2 + 1, q2, (q2 − 1)/2)-designs for odd prime powers q. In this note, we present the definition of the series and give some information about the automorphism groups of its members.

Quasi *-algebras and generalized inductive limits of C*-algebras

2011

On modified α-ϕ-fuzzy contractive mappings and an application to integral equations

2016

Abstract We introduce the notion of a modified α-ϕ-fuzzy contractive mapping and prove some results in fuzzy metric spaces for such kind of mappings. The theorems presented provide a generalization of some interesting results in the literature. Two examples and an application to integral equations are given to illustrate the usability of our theory.

Yhtälöryhmän iteratiivinen ratkaiseminen

2015

Guaranteed error bounds for linear algebra problems and a class of Picard-Lindelöf iteration methods

2012

This study focuses on iteration methods based on the Banach fixed point theorem and a posteriori error estimates of Ostrowski. Their application for systems of linear simultaneous equations, bounded linear operators, as well as integral and differential equations is considered. The study presents a new version of the Picard–Lindelöf method for ordinary differential equations (ODEs) supplied with guaranteed and explicitly computable upper bounds of the approximation error. The estimates derived in the thesis take into account interpolation and integration errors and, therefore, provide objective information on the accuracy of computed approximations.

Ortogonaalit latinalaiset neliöt

2013

Laskutehtävien suorittamisesta käsitteiden ymmärtämiseen : peruskoululaisen matemaattisen ajattelun kehittyminen aritmetiikasta algebraan siirryttäes…

2005

Kauko Hihnala tutki väitöstyössään peruskoulun matematiikan opiskelun ongelmia 6.-9. luokkalaisilla, erityisesti verrannollisuuden ja algebran alueilla. Hän huomasi, että oppilaiden peruslaskutaidot paranivat tasaisesti kuudennen luokan alusta yhdeksännen luokan loppuun asti. Kuitenkin monet yhdeksäsluokkalaiset tekivät mm. murtolukulaskuissa samoja alkeellisia virheitä kuin kuudesluokkalaiset. Oppilaskohtaiset suoritustason muutokset neljän vuoden seurannan aikana olivat huomattavia. Esimerkiksi kuudennen luokan alussa hyvin matematiikkaa osaavista vain puolet oli samalla tasolla peruskoulun päättyessä. Vastaava havainto tehtiin heikosti matematiikkaa osaavista.Suomen peruskoululaisten mat…

Su certe classi di gruppi unipotenti

2005

We introduce some results characterizing unipotent algebraic groups having a chain as the lattice of connected subgroups and we discuss some consequent results.

A simple methodology for comparing cost-benefit of traditional, green and cool roofs

2019

Energy policy makers, architects and researchers, when designing new buildings or rehabilitating the existing ones, are engaged in the attempt of limiting the energy needs for climatization (NZEB buildings) and the environmental pressure exerted by buildings (EU Climate Action). The pursuit of this demanding assignment calls for innovative solutions in conceiving the building envelope and its energy systems. Recently, among the most effective tools for improving the energy and environmental performances of buildings, the technical interventions regarding the roofs are gaining a rising attention. Indeed, covers of buildings are responsible of a relevant part of their energy losses and, on th…