Search results for " Representation."

The Representation Type of the Centre of a Group Algebra

1986

Groups with few $p'$-character degrees

2019

Abstract We prove a variation of Thompson's Theorem. Namely, if the first column of the character table of a finite group G contains only two distinct values not divisible by a given prime number p > 3 , then O p p ′ p p ′ ( G ) = 1 . This is done by using the classification of finite simple groups.

A characterisation of nilpotent blocks

2015

Let $B$ be a $p$-block of a finite group, and set $m=$ $\sum \chi(1)^2$, the sum taken over all height zero characters of $B$. Motivated by a result of M. Isaacs characterising $p$-nilpotent finite groups in terms of character degrees, we show that $B$ is nilpotent if and only if the exact power of $p$ dividing $m$ is equal to the $p$-part of $|G:P|^2|P:R|$, where $P$ is a defect group of $B$ and where $R$ is the focal subgroup of $P$ with respect to a fusion system $\CF$ of $B$ on $P$. The proof involves the hyperfocal subalgebra $D$ of a source algebra of $B$. We conjecture that all ordinary irreducible characters of $D$ have degree prime to $p$ if and only if the $\CF$-hyperfocal subgrou…

Almost polynomial growth: Classifying varieties of graded algebras

2015

Let G be a finite group, V a variety of associative G-graded algebras and c (V), n = 1, 2, …, its sequence of graded codimensions. It was recently shown by Valenti that such a sequence is polynomially bounded if and only if V does not contain a finite list of G-graded algebras. The list consists of group algebras of groups of order a prime number, the infinite-dimensional Grassmann algebra and the algebra of 2 × 2 upper triangular matrices with suitable gradings. Such algebras generate the only varieties of G-graded algebras of almost polynomial growth, i.e., varieties of exponential growth such that any proper subvariety is polynomially bounded. In this paper we completely classify all sub…

Research of a Cellular Automaton Simulating Logic Gates by Evolutionary Algorithms

2003

This paper presents a method of using genetic programming to seek new cellular automata that perform computational tasks. Two genetic algorithms are used : the first one discovers a rule supporting gliders and the second one modifies this rule in such a way that some components appear allowing it to simulate logic gates. The results show that the genetic programming is a promising tool for the search of cellular automata with specific behaviors, and thus can prove to be decisive for discovering new automata supporting universal computation.

Existence and uniqueness of solutions to superdifferential equations

1993

Abstract We state and prove the theorem of existence and uniqueness of solutions to ordinary superdifferential equations on supermanifolds. It is shown that any supervector field, X = X0 + X1, has a unique integral flow, Г: R 1¦1 x (M, AM) → (M, AM), satisfying a given initial condition. A necessary and sufficient condition for this integral flow to yield an R 1¦1-action is obtained: the homogeneous components, X0, and, X1, of the given field must define a Lie superalgebra of dimension (1, 1). The supergroup structure on R 1¦1, however, has to be specified: there are three non-isomorphic Lie supergroup structures on R 1¦1, all of which have addition as the group operation in the underlying …

Multiplexing AER asynchronous channels over LVDS links with flow-control and clock-correction for scalable neuromorphic systems

2017

Paper presented at the 2017 IEEE International Symposium on Circuits and Systems (ISCAS), held in Baltimore, MD, USA, on 28-31 May 2017.

Ventricular Fibrillation and Tachycardia Detection Using Features Derived from Topological Data Analysis

2022

A rapid and accurate detection of ventricular arrhythmias is essential to take appropriate therapeutic actions when cardiac arrhythmias occur. Furthermore, the accurate discrimination between arrhythmias is also important, provided that the required shocking therapy would not be the same. In this work, the main novelty is the use of the mathematical method known as Topological Data Analysis (TDA) to generate new types of features which can contribute to the improvement of the detection and classification performance of cardiac arrhythmias such as Ventricular Fibrillation (VF) and Ventricular Tachycardia (VT). The electrocardiographic (ECG) signals used for this evaluation were obtained from…

Morphological priming involves more than orthographic priming

2007

Los resultados de investigaciones recientes en reconocimiento visual de palabras apoyan cierta autonomía de las unidades morfológicas. Con el fin de investigar si los efectos de priming morfológico están producidos más por el solapamiento de forma que por las relaciones morfológicas de las palabras, se presenta un experimento de decisión léxica con priming enmascarado. Se comparan, mediante la utilización de las mismas palabras test (NUEVO), dos condiciones experimentales relativas a relaciones netamente ortográficas (nueve) y a relaciones morfológicas basadas en la marca de género (nueva). Los resultados de este estudio muestran que las palabras precedidas por otras con las que comparten u…

Percorsi relazionali nelle comunità. Minori, buone prassi e rappresentazioni a confronto.

2014

The aim of this thesis was to analyze the context of residential communities for young offenders (Part I) and to analyze the influence of social representations in adolescents and educators (Part II). The first part offers two levels of study on adolescents and on the organizational structure of the community. Adolescents show many problematic levels in the identified variables (Experiences of neglect and abuse during childhood, Attachment Styles, Self-Esteem, Interpersonal Relations, Behavioural problems). No differences between groups of young differentiating according to the reason for placement in community were found. Analysis of community (101 educators from 20 different households) w…