Search results for " Representation."
showing 10 items of 791 documents
Affine Kettengeometrien �ber Jordanalgebren
1996
It is shown that an affine chain geometry over a Jordan algebra can be constructed in a nearly classical manner. Conversely, such chain geometries are characterized as systems of rational normal curves having a group of automorphisms with certain properties.
The coordinatization of affine planes by rings
1996
With every unitary free module of rank 2 there is naturally associated a generalized affine plane (e.g. the lines are just the cosets of all nonzero 1-generated submodules). Here we solve the converse problem by coordinatizing a given generalized affine plane which satisfies certain versions of Desargues' postulate.
On the algebraic representation of projectively embeddable affine geometries
1995
The main result of this article is an application of [1] and [2] which yields that an at least 2-dimensional affine geometry is module-induced if and only if it is projectively embeddable into an Arguesian projective lattice geometry.
An Agent-Based Model of Extortion Racketeering
2016
Mafias can be considered as criminal organisations that are in the business of producing, promoting, and selling protection. Here, we describe the Palermo Scenario, an agent-based model of protection rackets aimed to deepen our understanding of protection rackets, and help policymakers to evaluate methods for destabilising them. Additionally, since the system is explicitly specified, we can use it to investigate the entire causal pathway from cause to effect: not only from actions to Mafia destabilisation, but also the intermediate actions along the path and actors' internal mental representations among the population.
Educational styles, peers’ approval and adolescent self-injurious behaviours
2010
The present research aims at understanding how the same body may became object of aggression and destruction by adolescents' self-injurious behaviours. Particularly, self-injurious behaviours are those finalised to destruction or deliberate alteration of one's body, even if without a conscious suicidal intention. The research aims at studying the relationship between educational styles, self-injurious behaviours and the social representation of the phenomenon in a group of adolescents aged between 15 and 19 years. Research has shown that on the basis of self-injurious behaviours there are the perception of an authoritarian educational style and approval by peers and brothers. (C) 2010 Elsev…
Media portrayals of transitions from work to retirement in two ageing societies : the case of ageing baby boomers in Japan and Finland
2021
This article explores media portrayals of the transition from work to retirement under the circumstances of demographic change through a focus on newspaper discussions about ageing baby boomers in Japan and Finland. Due to their shared characteristics as a distinct population group that advances the rapid ageing of the population, media representations of Japanese and Finnish baby boomers during the transitional period to retirement give insight into the social perceptions of retirement and their implications on later life. Manifest content analysis and subsequent thematic analysis identify that the topic of “work, retirement and pension” dominates media discussions in both countries. Analy…
Group graded algebras and almost polynomial growth
2011
Let F be a field of characteristic 0, G a finite abelian group and A a G-graded algebra. We prove that A generates a variety of G-graded algebras of almost polynomial growth if and only if A has the same graded identities as one of the following algebras: (1) FCp, the group algebra of a cyclic group of order p, where p is a prime number and p||G|; (2) UT2G(F), the algebra of 2×2 upper triangular matrices over F endowed with an elementary G-grading; (3) E, the infinite dimensional Grassmann algebra with trivial G-grading; (4) in case 2||G|, EZ2, the Grassmann algebra with canonical Z2-grading.
A note on cocharacter sequence of Jordan upper triangular matrix algebra
2016
Let UJn(F) be the Jordan algebra of n × n upper triangular matrices over a field F of characteristic zero. This paper is devoted to the study of polynomial identities satisfied by UJ2(F) and UJ3(F). In particular, the goal is twofold. On one hand, we complete the description of G-graded polynomial identities of UJ2(F), where G is a finite abelian group. On the other hand, we compute the Gelfand–Kirillov dimension of the relatively free algebra of UJ2(F) and we give a bound for the Gelfand–Kirillov dimension of the relatively free algebra of UJ3(F).
Actions of complex Lie groups on analytic ?-algebras
1987
On a reduced analytic .ℂ-algebraR there are faithful analytic actions of complex Lie groups of arbitrarily high dimension if and only ifR has Krull dimension ≥2.