Search results for " representation"
showing 10 items of 811 documents
RIFLESSIONI SU LINGUAGGIO E COGNIZIONE SPAZIALE Un confronto tra lingue vocali e lingue dei segni
2012
Depending on which theoretical paradigm is used, the relationship between spatial language and spatial thought could be presented in different ways. What is the nature of this relationship? Are spatial cognitive abilities a prerequisite for spatial language or, vice-versa, is it spatial language that shapes and affects our spatial reasoning? This paper is aimed at highlighting the dynamic interaction between spatial language and spatial cognition. That is, we need some spatial abilities in order to acquire spatial language. We share most of these core spatial abilities with other animals. These structures are the basis for spatial language, and this explains the presence of universal featur…
Covariant Operator Formalism for Quantized Superfields
1988
The Takahashi-Umezawa method of deriving the free covariant quantization relations from the linear equations of motion is extended to superfields. The Cauchy problem for free superfields is solved, and an expression for the time independent scalar product is given. For the case of interacting fields, we give the general Kallen-Lehmann spectral representation for the two-point superfield Green functions and, after the introduction of the asymptotic condition for superfields, we give the superfield extension of the Yang-Feldman equation. The case of the D = 2 real scalar superfield and the case of the D = 4 chiral superfield are discussed in detail.
Simplified spiking neural network architecture and STDP learning algorithm applied to image classification
2015
Spiking neural networks (SNN) have gained popularity in embedded applications such as robotics and computer vision. The main advantages of SNN are the temporal plasticity, ease of use in neural interface circuits and reduced computation complexity. SNN have been successfully used for image classification. They provide a model for the mammalian visual cortex, image segmentation and pattern recognition. Different spiking neuron mathematical models exist, but their computational complexity makes them ill-suited for hardware implementation. In this paper, a novel, simplified and computationally efficient model of spike response model (SRM) neuron with spike-time dependent plasticity (STDP) lear…
Spoken Word Production
2018
This chapter examines two distinct stages of the production of spoken words: the retrieval of semantic and lexical representations, followed by morphological and phonological processing. In both cases, it summarizes models of lexical representation and lexical selection that have focused on the retrieval of single words. These models agree that different lexical information becomes available at different points in time, with access to semantic and syntactic information preceding access to information about lexical form. The structure of this review reflects this dichotomy. Comprehensive production models must also account for the sequencing and timing of lexical processing in multiword utte…
How can mental models theory account for content effects in conditional reasoning? A developmental perspective
1998
Abstract This article proposes a modification to Johnson-Laird's mental models theory applied to the interpretation of conditional statement of the form `if...then'. The model suggests that this interpretation is based on the construction of mental models supplied by establishing a correspondence between the semantic spaces associated with the antecedent and consequent of the statements. The construction of the models and the interpretation of the statements would depend on the nature of the semantic spaces involved, the interpretative context and the subject's knowledge and processing capacity. Three experiments show that the interpretation of conditional rules depends, for example, on whe…
On the geometry of the characteristic class of a star product on a symplectic manifold
2001
The characteristic class of a star product on a symplectic manifold appears as the class of a deformation of a given symplectic connection, as described by Fedosov. In contrast, one usually thinks of the characteristic class of a star product as the class of a deformation of the Poisson structure (as in Kontsevich's work). In this paper, we present, in the symplectic framework, a natural procedure for constructing a star product by directly quantizing a deformation of the symplectic structure. Basically, in Fedosov's recursive formula for the star product with zero characteristic class, we replace the symplectic structure by one of its formal deformations in the parameter $\hbar$. We then s…
Requirement analysis abstractions for AmI system design
2015
Current trends in the AI’s evolution are going towards enriching environments with intelligence in order to support humans in their everyday life. AmI systems are plunged in the real world and humans expect to interact with them in a way that is similar to the one they have with other humans. In this kind of systems, where eliciting requirements involves several documents and stakeholders (mainly users that will be the first consumers of the system), the requirement analysis phase can be affected by incomplete, ambiguous and imprecise information. Hence, the need to find a fruitful way for knowledge management and its representation at design time. In this paper we propose a set of abstract…
Graphical representation of some duality relations in stochastic population models
2007
We derive a unified stochastic picture for the duality of a resampling-selection model with a branching-coalescing particle process (cf. http://www.ams.org/mathscinet-getitem?mr=MR2123250) and for the self-duality of Feller's branching diffusion with logistic growth (cf. math/0509612). The two dual processes are approximated by particle processes which are forward and backward processes in a graphical representation. We identify duality relations between the basic building blocks of the particle processes which lead to the two dualities mentioned above.
Fractional Brownian motion and Martingale-differences
2004
Abstract We generalize a result of Sottinen (Finance Stochastics 5 (2001) 343) by proving an approximation theorem for the fractional Brownian motion, with H> 1 2 , using martingale-differences.
A Knowledge Management and Decision Support Model for Enterprises
2011
We propose a novel knowledge management system (KMS) for enterprises. Our system exploits two different approaches for knowledge representation and reasoning: a document-based approach based on data-driven creation of a semantic space and an ontology-based model. Furthermore, we provide an expert system capable of supporting the enterprise decisional processes and a semantic engine which performs intelligent search on the enterprise knowledge bases. The decision support process exploits the Bayesian networks model to improve business planning process when performed under uncertainty. Copyright © 2011 Patrizia Ribino et al.