Search results for "symbolic"

Nondeterministic operations on finite relational structures

1998

Abstract This article builds on a tutorial introduction to universal algebra for language theory (Courcelle, Theoret. Comput. Sci. 163 (1996) 1–54) and extends it in two directions. First, nondeterministic operations are considered, i.e., operations which give a set of results instead of a single one. Most of their properties concerning recognizability and equational definability carry over from the ordinary case with minor modifications. Second, inductive sets of evaluations are studied in greater detail. It seems that they are handled most naturally in the framework presented here. We consider the analogues of top-down and bottom-up tree transducers. Again, most of their closure propertie…

"Legislative Inflation" - An analysis of the Phenomenon in Contemporary Legal Discourse

2011

Infinitesimal deformations of double covers of smooth algebraic varieties

2003

The goal of this paper is to give a method to compute the space of infinitesimal deformations of a double cover of a smooth algebraic variety. The space of all infinitesimal deformations has a representation as a direct sum of two subspaces. One is isomorphic to the space of simultaneous deformations of the branch locus and the base of the double covering. The second summand is the subspace of deformations of the double covering which induce trivial deformations of the branch divisor. The main result of the paper is a description of the effect of imposing singularities in the branch locus. As a special case we study deformations of Calabi--Yau threefolds which are non--singular models of do…

A New Set of Quartic Trivariate Polynomial Equations for Stratified Camera Self-calibration under Zero-Skew and Constant Parameters Assumptions

2012

This paper deals with the problem of self-calibrating a moving camera with constant parameters. We propose a new set of quartic trivariate polynomial equations in the unknown coordinates of the plane at infinity derived under the no-skew assumption. Our new equations allow to further enforce the constancy of the principal point across all images while retrieving the plane at infinity. Six such polynomials, four of which are independent, are obtained for each triplet of images. The proposed equations can be solved along with the so-called modulus constraints and allow to improve the performance of existing methods.

Exact Solutions of the Two Dimensional Boussinesq and Dispersive Water Waves Equations

2010

In this paper two-dimensional Boussinesq and dispersive water waves equations are investigated in exact solutions. The Exp-function method is used for seeking exact solutions of the equations through symbolic computation.

IA neuro-symbolique pour l'interprétation granulaire des données des bases STUPS© et OTARIES© : défis applicatifs et perspectives

2023

Historiquement, l'intelligence artificielle (IA) s'est divisée en 2 courants selon les hypothèses faites pour modéliser l'intelligence humaine : l'IA symbolique, supposant que des symboles sont nécessaires, et l'IA statistique (plus particulièrement l'IA connexionniste) affirmant le contraire. Dernièrement, l'IA neuro-symbolique tente de réconcilier les 2. Les travaux présentés dans cet article sont en en collaboration avec la Police Scientifique française, dans le contexte du Plan National Stup. Nous présentons les problématiques métiers en lien avec le projet, puis en déduisons les problématiques scientifiques. Après un rappel des domaines de l'IA et leurs limites, nous présentons un état…

Construction of a fundamental set of solutions of an arbitrary homogeneous linear difference equation

2002

Abstract The detailed construction of a prefixed fundamental set of solutions of a linear homogeneous difference equation of any order with arbitrarily variable coefficients is reported. The usefulness of the resulting resolutive formula is illustrated by simple applications to the Hermite polynomials and to the Fibonacci sequence.

The taboo against group contact: Hypothesis of Gypsy ontologization

2007

The concept of this article is that the symbolic relationships between human beings and animals serve as a model for the relationships between the majority and the ethnic minority. We postulate that there are two representations that serve to organize these relationships between human beings and animals: a domestic and a wild one. If the domestic animal is an index of human culture, the wild animal is an index of nature which man considers himself to share with the animal. With the wild representation, contact with the animal will be taboo, as it constitutes a threat to the anthropological difference. We offer the hypothesis that ontologization of the minority, that is, the substitution of …

How Universal Is the Relationship between Remotely Sensed Vegetation Indices and Crop Leaf Area Index? A Global Assessment

2016

This study aims to assess the relationship between Leaf Area Index (LAI) and remotely sensed Vegetation Indices (VIs) for major crops, based on a globally explicit dataset of in situ LAI measurements over a significant set of locations. We used a total of 1394 LAI measurements from 29 sites spanning 4 continents and covering 15 crop types with corresponding Landsat satellite images. Best-fit functions for the LAI-VI relationships were generated and assessed in terms of crop type, vegetation index, level of radiometric/atmospheric processing, method of LAI measurement, as well as the time difference between LAI measurements and satellite overpass. These global LAI-VI relationships were evalu…

Rapid construction of algebraic axioms from samples

1991

Abstract An axiom is called reliable if it is confirmed in several places in a given sample of algebra. A very effective algorithm for enumerating such axioms is described.