Êtes-vous un étudiant de l'EPFL à la recherche d'un projet de semestre?

Travaillez avec nous sur des projets en science des données et en visualisation, et déployez votre projet sous forme d'application sur GraphSearch.

Découvrez-en plus sur les applications Graph.

Graph
Search

fr|en

Se Connecter

Concept

Multiplication

Résumé

thumb|La multiplication de 4 par 3 donne le même résultat que la multiplication de 3 par 4. La multiplication est l'une des quatre opérations de l'arithmétique élémentaire avec l'addition, la soustraction et la division. Cette opération est souvent notée avec la croix de multiplication « × », mais peut aussi être notée par d'autres symboles (par exemple le point médian « · ») ou par l'absence de symbole. Son résultat s'appelle le produit, les nombres que l'on multiplie sont les facteurs. La multiplication de deux nombres a et b se dit indifféremment en français « a multiplié par b » ou « b fois a ». La multiplication de deux nombres entiers peut être vue comme une addition répétée plusieurs fois. Par exemple, « 3 fois 4 » peut se voir comme la somme de trois nombres 4 ; « 4 fois 3 » peut se voir comme la somme de quatre nombres 3 : :3 fois 4 = 4 multiplié par 3 = 4 × 3 = 4 + 4 + 4 ; :4 fois 3 = 3 multiplié par 4 = 3 × 4 = 3 + 3 + 3 + 3 ; avec : La mul

Source officielle

https://fr.wikipedia.org/wiki/Multiplication

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Publications associées (31)

Publications associées

Chargement

Personnes associées (1)

Personnes associées

Chargement

Unités associées (1)

Unités associées

Chargement

Concepts associés (115)

Concepts associés

Chargement

Cours associés (74)

The purpose of the course is to introduce the basic notions of linear algebra and its applications.

L'objectif du cours est d'introduire les notions de base de l'algèbre linéaire et de démontrer rigoureusement les résultats principaux de ce sujet.

Study the basics of representation theory of groups and associative algebras.

Afficher plus

Cours associés

Chargement

Séances de cours associées (137)

Séances de cours associées

Chargement

Motivated by the work of Kupershmidt (J. Nonlin. Math. Phys. 6 (1998), 222 -245) we discuss the occurrence of left symmetry in a generalized Virasoro algebra. The multiplication rule is defined, which is necessary and sufficient for this algebra to be quasi-associative. Its link to geometry and nonlinear systems of hydrodynamic type is also recalled. Further, the criteria of skew-symmetry, derivation and Jacobi identity making this algebra into a Lie algebra are derived. The coboundary operators are defined and discussed. We deduce the hereditary operator and its generalization to the corresponding 3 ary bracket. Further, we derive the so-called rho compatibility equation and perform a phase-space extension. Finally, concrete relevant particular cases are investigated.

Taylor & Francis Ltd2016

Chargement

Computational Aspects of Jacobians of Hyperelliptic Curves

Alina Dudeanu

Nowadays, one area of research in cryptanalysis is solving the Discrete Logarithm Problem (DLP) in finite groups whose group representation is not yet exploited. For such groups, the best one can do is using a generic method to attack the DLP, the fastest of which remains the Pollard rho algorithm with

r

-adding walks. For the first time, we rigorously analyze the Pollard rho method with

r

-adding walks and prove a complexity bound that differs from the birthday bound observed in practice by a relatively small factor. There exist a multitude of open questions in genus

2

cryptography. In this case, the DLP is defined in large prime order subgroups of rational points that are situated on the Jacobian of a genus~

2

curve defined over a large characteristic finite field. We focus on one main topic, namely we present a new efficient algorithm for computing cyclic isogenies between Jacobians. Comparing to previous work that computes non cyclic isogenies in genus~

2

, we need to restrict to certain cases of polarized abelian varieties with specific complex multiplication and real multiplication. The algorithm has multiple applications related to the structure of the isogeny graph in genus~

2

, including random self-reducibility of DLP. It helps support the widespread intuition of choosing \emph{any} curve in a class of curves that satisfy certain public and well studied security parameters. Another topic of interest is generating hyperelliptic curves for cryptographic applications via the CM method that is based on the numerical estimation of the rational Igusa class polynomials. A recent development relates the denominators of the Igusa class polynomials to counting ideal classes in non maximal real quadratic orders whose norm is not prime to the conductor. Besides counting, our new algorithm provides precise representations of such ideal classes for all real quadratic fields and is part of an implementation in Magma of the recent theoretic work in the literature on the topic of denominators.

EPFL2016

Chargement

The Autonomous Photovoltaic MarXbot

Francesco Mondada, Philippe Rétornaz, Florian Christopher Vaussard

Domestic service robots are currently powered by the mains electricity. The growing multiplication of such devices negatively impacts our environment. In this study, we show the feasibility of harvesting energy from natural light in an indoor environment. The design of the harvester is carefully carried out using an experimental characterisation of several solar panels, while the boost converter is optimised to operate at low-light intensities and the robot is enhanced for low-power operations. The resulting harvester is then thoroughly characterised. Finally, a phototaxis experiment is conducted, proving the feasibility of recharging the robot solely by using this form of energy. The possibility of embedding energy harvesting in indoor mobile robots radically changes the potential impact of this technology in our society.

Springer Berlin Heidelberg2013

Chargement

Computational Aspects of Jacobians of Hyperelliptic Curves

Alina Dudeanu

r

-adding walks. For the first time, we rigorously analyze the Pollard rho method with

r

-adding walks and prove a complexity bound that differs from the birthday bound observed in practice by a relatively small factor. There exist a multitude of open questions in genus

2

cryptography. In this case, the DLP is defined in large prime order subgroups of rational points that are situated on the Jacobian of a genus~

2

2

2

EPFL2016