Search results for "RJ"

Lehmer code transforms and Mahonian statistics on permutations

2012

Abstract In 2000 Babson and Steingrimsson introduced the notion of vincular patterns in permutations. They show that essentially all well-known Mahonian permutation statistics can be written as combinations of such patterns. Also, they proved and conjectured that other combinations of vincular patterns are still Mahonian. These conjectures were proved later: by Foata and Zeilberger in 2001, and by Foata and Randrianarivony in 2006. In this paper we give an alternative proof of some of these results. Our approach is based on permutation codes which, like the Lehmer code, map bijectively permutations onto subexcedant sequences. More precisely, we give several code transforms (i.e., bijections…

Decomposable Measures and Measures of Information for Crisp and Fuzzy Sets

1983

Abstract There exist bijections between the decomposable informations of Kampe de Feriet and Forte (1967a) and the decomposable measures of Weber (1982). Using integrals for Archimedean decomposable operations, introduced by Weber (1982), informations and measures of this type are extended from crisp to fuzzy sets. For ∨-decomposable measures, Sugeno’s (1974) integral is used. For ∧-decomposable informations, Nguyen’s (1977) construction and a modification are discussed.

Perturbations of surjective convolution operators

2002

Let μ 1 and μ 2 be (ultra)distributions with compact support which have disjoint singular supports. We assume that the convolution operator f → μ 1 *f is surjective when it acts on a space of functions or (ultra)distributions, and we investigate whether the perturbed convolution operator f→ (μ 1 + μ 2 ) * f is surjective. In particular we solve in the negative a question asked by Abramczuk in 1984.

Existence theorems for m-accretive operators in Banach spaces

2005

Abstract In 1985, the second author proved a surjective result for m -accretive and ϕ -expansive mappings for uniformly smooth Banach spaces. However, in this case, we have been able to remove the uniform smoothness of the Banach space, without any additional assumption.

An extension of the Burrows-Wheeler Transform and applications to sequence comparison and data compression

2005

We introduce a generalization of the Burrows-Wheeler Transform (BWT) that can be applied to a multiset of words. The extended transformation, denoted by E, is reversible, but, differently from BWT, it is also surjective. The E transformation allows to give a definition of distance between two sequences, that we apply here to the problem of the whole mitochondrial genome phylogeny. Moreover we give some consideration about compressing a set of words by using the E transformation as preprocessing.

The surjective hull of a polynomial ideal

2016

The aim of this paper is the study of surjective ideals of homogeneous polynomials between Banach spaces. To do so we define the surjective hull of a polynomial ideal and prove the main properties of this hull procedure. For a more comprehensive theory, new lifting properties of homogeneous polynomials are proved and applied to the description of the surjective hulls of the ideals of I-bounded polynomials and of composition polynomials ideals. Several applications are provided.

Butterflies in a Semi-Abelian Context

2011

It is known that monoidal functors between internal groupoids in the category Grp of groups constitute the bicategory of fractions of the 2-category Grpd(Grp) of internal groupoids, internal functors and internal natural transformations in Grp, with respect to weak equivalences (that is, internal functors which are internally fully faithful and essentially surjective on objects). Monoidal functors can be equivalently described by a kind of weak morphisms introduced by B. Noohi under the name of butterflies. In order to internalize monoidal functors in a wide context, we introduce the notion of internal butterflies between internal crossed modules in a semi-abelian category C, and we show th…

Restriction of odd degree characters and natural correspondences

2016

Let $q$ be an odd prime power, $n > 1$, and let $P$ denote a maximal parabolic subgroup of $GL_n(q)$ with Levi subgroup $GL_{n-1}(q) \times GL_1(q)$. We restrict the odd-degree irreducible characters of $GL_n(q)$ to $P$ to discover a natural correspondence of characters, both for $GL_n(q)$ and $SL_n(q)$. A similar result is established for certain finite groups with self-normalizing Sylow $p$-subgroups. We also construct a canonical bijection between the odd-degree irreducible characters of $S_n$ and those of $M$, where $M$ is any maximal subgroup of $S_n$ of odd index; as well as between the odd-degree irreducible characters of $G = GL_n(q)$ or $GU_n(q)$ with $q$ odd and those of $N_{G}…

Ihmeellinen ERP : toiminnanohjausjärjestelmien esittelymateriaalien ja järjestelmien kriittisen tutkimuksen väliset ristiriidat

2016

Tässä tutkimuksessa selvitettiin, kuinka toiminnanohjausjärjestelmien toimittajien esittelemät järjestelmäperustelut poikkeavat järjestelmien kriittisten tutkimusten näkemyksistä. Esittelymateriaalien perusteluita ja kriittisiä tutkimuksia vertailemalla tutkimus pyrki tarjoamaan järjestelmän käyttöönottoa harkitseville yrityksille kriittisen näkökulman järjestelmien esittelymateriaalien tarkasteluun. Tutkimus edustaa laadullista tutkimusta, joka on tyypiltään kartoittavaa ja osin tulkit-sevaa ja kriittistä tutkimusta. Koska tutkimus huomioi erityisesti aineiston kielellisiä piirteitä, diskurssitutkimuksen näkökulmat olivat tutkimuksessa keskeisiä. Tutkimuksen aineisto muodostui kolmen Suome…

Pitkäaikaistyöttömyys yhteiskunnan rakenteissa : tutkimus pitkäaikaistyöttömyyden diskursseista

2014