North-Western European Journal of Mathematics

ISSN=2496-5170

The Lille Main Square

Aims and scope

The North-Western European Journal of Mathematics publishes research articles and surveys in all areas of pure and applied mathematics including history of mathematics. Articles can be submitted in Dutch, English, French or German.

Policies

Peer Review Process

The reviewing process is simple anonymous, that is the reviewers are kept anonymous while the authors are not. The authors are asked to provide the names of one or two potential associate editors who will manage their article. Then, the editor in chief assigns the article to an associate editor who seeks reviewer(s). Once the reviews are available, the associate editor reports his decision to the whole editorial board which takes the final decision regarding the acceptance of the article.

Open Access Policy

The North-Western European Journal of Mathematics adheres to the principles of Fair Open Access, and is a member of the Free Journal Network. No charges are levied on authors. Articles are freely available to anyone as soon they are accepted. Hard copies of a volume are available at the cost of the paper and delivery.

Authors keep their copyrights. Thus they can reuse figures, article parts or any material they need for subsequent work. The contract license is the Creative Commons License CC-BY which is the most flexible contract maximising the readership on publication.

Author Guidelines

Articles submission: At the initial stage, the authors have only to provide a file in the pdf format. Only when the article is accepted or subject to minor revisions are they asked to ensure it complies with the journal format.

LaTeX details:

• LaTeX class: We strongly encourage the authors to prepare their article to appear in the NWEJM journal with the dedicated nwejmart' LaTeX class (currently, documented only in French), available with up to date MiKTeX 2.9 and TeX Live 2016 distributions.
• Incompatibilities:>
• Our production system is not compatible with the xypic' bundle. For commutative diagramms, please use instead the user-friendly and modern tikz-cd' package.
• We much more prefer graphics not created with PSTricks' and derived. Consider using PGF'/TikZ' or derived packages. In case you really need one of these packages, please contact us.
• Bibliography: The bibliography must be provided as a .bib' file in the format of the biblatex' package.
• Figures: The figures must be provided in PDF or EPS formats.

Here you can find an example of a LaTEX and a biblatex file. The template and the documentation (for the time being only in French). Articles should be sent by mail to the managing editor (nicolas.wickerNOSPAMATuniv-lille.fr).

Current Volume:

The current volume is the volume of 2021.
• We obtained a moment estimate for the sum of Rademacher random variables under condition that they are dependent in the way that their sum is zero.
• Let $A$ be a nonempty finite subset of $\mathbb{Z}^d$ which is not contained in a hyperplane, $q\in\mathbb{Z}$ with $|q|>1$ and $m\in \mathbb{Z}$ such that $|q|+2d-1\leq m\leq (|q|+2d-1)^2$. In this paper it is shown that \begin{equation*} |A+q\cdot A|\geq \left(\frac{m}{|q|+2d-1}\right)|A|-c \end{equation*} where $c$ depends only on $q,d$ and $m$. In particular, taking $m=(|q|+2d-1)^2$, this results confirms a conjecture of A. Balog and G. Shakan.
• In this paper, we study a class of convolution operators on the space of distributions that enlarge the well-studied class of passive operators. In this larger class, we are able to associate, to each operator, a holomorphic function in the right half-plane with a specific constraint on its range, determined by the operator. Afterwards, we investigate whether the properties of causality and slow growth hold automatically in our larger class of convolution operators. Finally, an alternative class of convolution operators is also considered.
• In this paper, we consider the space of entire functions of minimal type growth for a proximate order. We study the surjectivity of corresponding infinite order differential equations in the cases of regular singular type and of Korobeǐnik type.
• We obtain expected number of arrivals, absorption probabilities and expected time until absorption for an asymmetric discrete random walk on a graph in the presence of multiple function barriers. On each edge of the graph and in each vertex (barrier) specific probabilities are defined.
• Les E- et G-fonctions de Siegel ont été définies en deux sens, strict et large, conjecturalement équivalents. En reprenant et complétant une esquisse d’André, nous énonçons et démontrons l’analogue au sens large du théorème d’André-Chudnovsky-Katz, qui est un théorème de structure sur les G-opérateurs au sens strict (il s’agit d’opérateurs différentiels annulant les G-fonctions au sens strict). Nous en déduisons un théorème de structure sur les E-opérateurs au sens large, qui sont des opérateurs différentiels annulant les E-fonctions au sens large. En application de ce dernier théorème, nous donnons une nouvelle preuve d’une généralisation par André du théorème de Siegel-Shidlovskii sur l’indépendance algébrique des valeurs des E-fonctions au sens large.
• In Coulombel (2015) a multiplier technique, going back to Leray and Gård- ing for scalar hyperbolic partial differential equations, has been extended to the context of finite difference schemes for evolutionary problems. The key point of the analysis in Coulombel (2015) was to obtain a discrete energy-dissipation balance law when the initial difference operator is multiplied by a suitable quan- tity (the so-called multiplier). The construction of the energy and dissipation functionals was achieved in Coulombel (2015) under the assumption that all modes were separated. We relax this assumption here and construct, for the same multiplier as in Coulombel (2015), the energy and dissipation functionals when some modes cross. Semigroup estimates for fully discrete hyperbolic initial boundary value problems are deduced in this broader context.

Acknowledgements

This journal owes much to the following persons: Denis Bitouzé for LaTex support, Jean-Jacques Derycke for printing service, Sébastien Huart for wicker computer engineering issues and Aurore Smets for secretarial tasks.

Supports

The department of Mathematics of Lille 1 provides financial support which ensures that this journal stays open access. The French Mathematical Society (SMF), the Dutch Mathematical Society (KWG), the Luxembourg Mathematical Society (SML) and the Fields Institute support this project, of a mathematics journal by a non-profit publisher, making research available free of charge for readers and authors.

Auxiliary Material

A slide to present the journal.

Friends

We provide a tentative list of journal friends, i.e. diamond open access journals free of charge for authors and readers.