Search results for "informatica"

Clean air, technology, glocalization: how can we clean up the Planet with small little actions that resonate globally? Blockchain may be the answer

2022

Amongst the lessons that the Covid-19 pandemic has taught us, there is at least one lesson for each of these three words: clean air, technology and glocalization. Clean air: research has noticed a link between polluted air and the spread of the virus, in a game where the former helps the latter. Do we need further evidence that polluted air is bad? Technology: smart working, schools, everything during lockdown functions thanks to stable internet and connected devices. Glocalization: small actions can resonate, as a virus can spread if citizens move across countries or go out without wearing masks. To make sure we reach our goals – be them the UN Sustainable Development Goals, the thresholds…

Information-theoretic assessment of cardiovascular variability during postural and mental stress

2016

This study was aimed at investigating the individual and combined effects of postural and mental stress on short-term cardiovascular regulation. To this end, we applied measures taken from the emerging framework of information dynamics on the beat-to-beat spontaneous variability of RR interval and systolic arterial pressure (SAP) measured from healthy subjects in the resting supine position and during the separate and simultaneous execution of experimental protocols performing head-up tilt (HUT) and mental arithmetics (MA). The information stored in RR interval variability, a measure inversely related to the complexity of the time series, increased significantly during HUT and HUT+MA compar…

An identifiable model to assess frequency-domain Granger causality in the presence of significant instantaneous interactions

2010

We present a new approach for the investigation of Granger causality in the frequency domain by means of the partial directed coherence (PDC). The approach is based on the utilization of an extended multivariate autoregressive (MVAR) model, including instantaneous effects in addition to the lagged effects traditionally studied, to fit the observed multiple time series prior to PDC computation. Model identification is performed combining standard MVAR coefficient estimation with a recent technique for instantaneous causal modeling based on independent component analysis. The approach is first validated on simulated MVAR processes showing that, in the presence of instantaneous effects, only t…

Seven Mathematical Models of Hemorrhagic Shock

2021

Although mathematical modelling of pressure-flow dynamics in the cardiocirculatory system has a lengthy history, readily finding the appropriate model for the experimental situation at hand is often a challenge in and of itself. An ideal model would be relatively easy to use and reliable, besides being ethically acceptable. Furthermore, it would address the pathogenic features of the cardiovascular disease that one seeks to investigate. No universally valid model has been identified, even though a host of models have been developed. The object of this review is to describe several of the most relevant mathematical models of the cardiovascular system: the physiological features of circulator…

Time, frequency and information domain analysis of short-term heart rate variability before and after focal and generalized seizures in epileptic chi…

2019

OBJECTIVE In this work we explore the potential of combining standard time and frequency domain indexes with novel information measures, to characterize pre- and post-ictal heart rate variability (HRV) in epileptic children, with the aim of differentiating focal and generalized epilepsy regarding the autonomic control mechanisms. APPROACH We analyze short-term HRV in 37 children suffering from generalized or focal epilepsy, monitored 10 s, 300 s, 600 s and 1800 s both before and after seizure episodes. Nine indexes are computed in time (mean, standard deviation of normal-to-normal intervals, root mean square of the successive differences (RMSSD)), frequency (low-to-high frequency power rati…

A new framework for the time- and frequency-domain assessment of high-order interactions in networks of random processes

2022

While the standard network description of complex systems is based on quantifying the link between pairs of system units, higher-order interactions (HOIs) involving three or more units often play a major role in governing the collective network behavior. This work introduces a new approach to quantify pairwise and HOIs for multivariate rhythmic processes interacting across multiple time scales. We define the so-called O-information rate (OIR) as a new metric to assess HOIs for multivariate time series, and present a framework to decompose the OIR into measures quantifying Granger-causal and instantaneous influences, as well as to expand all measures in the frequency domain. The framework ex…

Technology and human sciences: A dialogue to be constructed or a common tread to be rediscovered?

2013

In this contribution we begin to discuss the thesis that an analysis of the similarities and differences of typical methodologies of human sciences, technology and hard sciences show some unforeseen but strong similarities between human sciences and technologies. In this context fuzzy sets ideas provide useful tools which help to render the analysis more quantitative but without loosing the connection with a purely descriptive analysis. These kinds of considerations would have been hardly conceivable in the setting of XIX Century conception of science. It is the development of Information sciences that has allowed these problems to emerge. In this paper we shall then briefly outline the gen…

Estudio del Impacto de las Nuevas Tecnologías en las personas con discapacidad

2001

Optimal Parsing for Dictionary Text Compression

2012

Dictionary-based compression algorithms include a parsing strategy to transform the input text into a sequence of dictionary phrases. Given a text, such process usually is not unique and, for compression purpose, it makes sense to find one of the possible parsing that minimize the final compression ratio. This is the parsing problem. An optimal parsing is a parsing strategy or a parsing algorithm that solve the parsing problem taking account of all the constraints of a compression algorithm or of a class of homogeneous compression algorithms. Compression algorithm constrains are, for instance, the dictionary itself, i.e. the dynamic set of available phrases, and how much a phrase weights on…

Analysis and Comparison of Deep Learning Networks for Supporting Sentiment Mining in Text Corpora

2020

In this paper, we tackle the problem of the irony and sarcasm detection for the Italian language to contribute to the enrichment of the sentiment analysis field. We analyze and compare five deep-learning systems. Results show the high suitability of such systems to face the problem by achieving 93% of F1-Score in the best case. Furthermore, we briefly analyze the model architectures in order to choose the best compromise between performances and complexity.