Search results for "Temporal"
showing 10 items of 1095 documents
Weighted local second-order statistics for complex spatio-temporal point processes
2019
Spatial, temporal, and spatio-temporal point processes, and in particular Poisson processes, are stochastic processes that are largely used to describe and model the distribution of a wealth of real phenomena. When a model is fitted to a set of random points, observed in a given multidimensional space, diagnostic measures are necessary to assess the goodness-of-fit and to evaluate the ability of that model to describe the random point pattern behaviour. The main problem when dealing with residual analysis for point processes is to find a correct definition of residuals. Diagnostics of goodness-of-fit in the theory of point processes are often considered through the transformation of data in…
Spatio-temporal Dynamical Analysis of Brain Activity during Mental Fatigue Process
2021
Mental fatigue is a common phenomenon with implicit and multidimensional properties. It brings dynamic changes of functional brain networks. However, the challenging problem of false positives appears when the connectivity is estimated by Electroencephalography (EEG). In this paper, we propose a novel framework based on spatial clustering to explore the sources of mental fatigue and functional activity changes caused by them. To suppress the false positive observations, spatial clustering is implemented in brain networks. The nodes extracted by spatial clustering are registered back to functional magnetic resonance imaging (fMRI) source space to determined the sources of mental fatigue. The…
SEMANTIC AND CONTEXTUAL APPROACH FOR THE RECOMMENDATION OF LEARNING MODULES IN MOBILITY
2012
International audience; Many researchers argue that mobile learning is just an adaptation of e-learning on mobile technology, but far from a simple extension of e-learning, m-learning raises original issues in technological and pedagogical terms. M-learning is usually based on the consideration of a context rich on information and interactions. The challenge of m-learning is therefore, not simply to transfer on mobile content designed primarily for e-learning. This concept implies that we must rethink the entire process of the learning experience in mobility to maximize its efficiency.
Recommender system for combination of learning elements in mobile environment
2012
5 pages; International audience; The paper presents an ongoing research about the development of a new recommender system dedicated to m-learning. This system is an extension of content based recommender system proposals. It's made of three levels architecture: 1/ a domain model describing the knowledge of teaching, 2/ a user model defining learner's profile and learning's context, 3/ an adaptation model containing rules and metaheuristics, which aims at combining learning modules. Our system takes into account the spatio-temporal context of the learners, the evolution of learner's profile and the dynamic adaptation of modules during the learning process in a mobile environment. The result …
Theoretical approaches and frameworks to language maintenance and shift research : a critical review
2019
This article presents a critical overview of theoretical approaches and frameworks to language maintenance and shift research in the area of immigrant languages. It covers the underlying principles of these frameworks and assesses their advantages and shortcomings. The article argues that the field’s theoretical orientations have shifted recently, with a greater emphasis on understanding language maintenance and shift as a dynamic process involving complex interrelationships between space and time. These new trends and new areas of research in relation to language maintenance and shift are highlighted and discussed in different parts of the article. The article concludes by calling on the s…
Temporal trends of heavy metals in sediment core from the gulf of Palermo (Sicily, Italy)
2009
The evaluation of long–term heavy metal concentrations in the Gulf of Palermo was carried out in this study. Measurements of Cr, Cu, Hg, Pb and Zn concentrations were performed by atomic absorption spectrophotometry (AAS) on dated fractions of a sediment core, dated by the 210Pbex method. They are found to cover a time period from 1951 to 2004. The constant sedimentation rate model was used for dating. Specific activities of 137Cs have also been measured in the sediment core sections as a check of the time scale derived by the 210Pbex method. A time-series analysis based on temporal decomposition was used in order to investigate the presence of heavy metal pollution trend. The additive comp…
Variazioni temporali della struttura di taglia in popolazioni sfruttate di Haliotis tuberculata (Mollusca Gastropoda) nel Golfo di Sferracavallo (PA)
2007
This study aims at evaluating the differences in size structure of population of H. tuberculata in the Gulf of Sferracavallo (northern Sicily) which experienced the co-occurrence of high exploitation and decrease of eutrophic conditions during the eighties and early nineties. Comparison of size structure showed significant differences between length frequency distributions of 1970-75s and 2002-2005, being the latter formed by smaller size green ormer.
Autorreflexión pedagógica
2019
The autobiographical reflection on school learning makes it possible to explain how personal life guidelines are loading teaching activity with experiences. Educational time does not consist only of a linear narration, but works as the evocation of temporal and spatial memories of an explanation of the present. Personal life is intertwined with school reflection to give meaning to what we decide from teaching
A Repository for Multirelational Dynamic Networks
2012
Nowadays, WWW contains a number of social media sites, which are growing rapidly. One of the main features of social media sites is to allow to its users creation and modification of contents of the site utilizing the offered WWW interfaces. Such contents are referred to as user generated contents and their type varies from site to site. Social media sites can be modeled as constantly evolving multirelational directed graphs. In this paper we discuss persistent data structures for such graphs, and present and analyze queries performed against the structures. We also estimate the space requirements of the proposed data structures, and compare them with the naive "store each complete snapshot…
A modelling framework for social media monitoring
2013
This paper describes a hierarchical, three-level modelling framework for monitoring social media. Immediate social reality is modelled through the first level of the models. They represent various virtual communities at social media sites and adhere to the social world models of the sites, i.e., the "site ontologies". The second-level model is a temporal multirelational graph that captures the static and dynamic properties of the first-level models from the perspective of the monitoring site. The third-level model consists of a temporal relational database scheme that models the temporal multirelational graph within the database. The models are specified and instantiated at the monitoring s…