Search results for "symbolic"
showing 10 items of 449 documents
CliffoSor: A Parallel Embedded Architecture for Geometric Algebra and Computer Graphics
2006
Geometric object representation and their transformations are the two key aspects in computer graphics applications. Traditionally, compute-intensive matrix calculations are involved to model and render 3D scenery. Geometric algebra (a.k.a. Clifford algebra) is gaining growing attention for its natural way to model geometric facts coupled with its being a powerful analytical tool for symbolic calculations. In this paper, the architecture of CliffoSor (Clifford Processor) is introduced. ClifforSor is an embedded parallel coprocessing core that offers direct hardware support to Clifford algebra operators. A prototype implementation on an FPGA board is detailed. Initial test results show more …
Inversion of matrix pencils for generalized systems
1993
Abstract This paper clarifies the nature of the Leverrier-Faddeev algorithm for generalized and state-space systems. It presents useful diagrams for recursive computation of the coefficients of the characteristic polynomial and the coefficient matrices of the adjoint matrix for various matrix pencils. A simplified case covers recursive equations and diagrams for inversion of the second-order matrix pencil (Es2 + A1s + A0) where E may be singular. The appendix provides two examples of mechanical and heat exchange systems which can be described by the generalized models.
Substitution systems and nonextensive statistics
2015
Abstract Substitution systems evolve in time by generating sequences of symbols from a finite alphabet: At a certain iteration step, the existing symbols are systematically replaced by blocks of N k symbols also within the alphabet (with N k , a natural number, being the length of the k th block of the substitution). The dynamics of these systems leads naturally to fractals and self-similarity. By using B -calculus (Garcia-Morales, 2012) universal maps for deterministic substitution systems both of constant and non-constant length, are formulated in 1D. It is then shown how these systems can be put in direct correspondence with Tsallis entropy. A ‘Second Law of Thermodynamics’ is also prove…
A more efficient second order blind identification method for separation of uncorrelated stationary time series
2016
The classical second order source separation methods use approximate joint diagonalization of autocovariance matrices with several lags to estimate the unmixing matrix. Based on recent asymptotic results, we propose a novel unmixing matrix estimator which selects the best lag set from a finite set of candidate sets specified by the user. The theory is illustrated by a simulation study.
Higher order matrix differential equations with singular coefficient matrices
2015
In this article, the class of higher order linear matrix differential equations with constant coefficient matrices and stochastic process terms is studied. The coefficient of the highest order is considered to be singular; thus, rendering the response determination of such systems in a straightforward manner a difficult task. In this regard, the notion of the generalized inverse of a singular matrix is used for determining response statistics. Further, an application relevant to engineering dynamics problems is included.
Subjectivisation and feminism. An analysis of a political manifesto
2004
The theme of this article is the the Italian feminist movement of the 1980s. That movement was characterised by political transformation and a crtitique of identity. The article takes as its point of departure the inaugural speech of the movement, the manifesto "Piu donne che uomini" (1983). The analysis that we present is inspired in the work of Michel Foucault. It aims to show to that the production of new feministic subjectivities, when fighting the symbolic dimension of masculine domination, has an intrinsically political character. In the 1980s, in the Italian context and particularly in the feminist movement, the rules of the political game set up by the events of 1968 materialized. T…
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…
Some Notes About Distribution Frame Multipliers
2020
Inspired by a recent work about distribution frames, the definition of multiplier operator is extended in the rigged Hilbert spaces setting and a study of its main properties is carried on. In particular, conditions for the density of domain and boundedness are given. The case of Riesz distribution bases is examined in order to develop a symbolic calculus.
Consumers’ criteria to select food retailers revisited in the current environment.
2022
Food retailing is undergoing major transformations, particularly in France. Hypermarkets are declining, hard-discount stores are gentrifying, e-commerce is mixing with physical distribution, convenience stores are gaining presence and market shares, other forms are emerging: short, collaborative or cooperative channels. Consumers are clearly changing their buying patterns. How do people currently select a form of sale? Are there any changes in their selection criteria or in their perception of food retailing that can explain that they are turning away from hypermarkets to go to more meaningful places? The objective of this research is to revisit the consumers’ criteria to select a form of s…
Another defence of enumerated types
1991
I claim that enumerations, while of course not strictly necessary, are an elegant and useful facility in modern programming languages. I try to show that arguments recently given against them are weak at best and bogus a t worst, for general-purpose programming. Some related issues on types in programming languages are touched as well. These make it even more questionable whether Oberon marks progress or regress in language design.