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TURISMO E SVILUPPO
No full textNonostante la continua crescita del turismo mondiale, in Italia il comparto sta attraversando una fase di difficoltà. Il Paese perde capacità competitive e la sua posizione internazionale è attaccata da vecchie e nuove mete internazionali. Con l’esplosione di internet in tutto il mondo la filiera turistica si contrae, i nuovi visitatori sono sempre più motivati, attenti alla qualità e al prezzo ma in tutta Italia la struttura dell’offerta fatica ad adeguarsi alle caratteristiche della nuova domanda. L’assenza di una struttura di coordinamento nazionale, la frammentazione delle iniziative per la comunicazione, la scarsità di efficaci strutture di ricerca e di informazione contribuiscono a mettere in luce, fra l’altro, come il settore manchi di standing internazionale. L’Italia possiede enormi risorse competitive allo stato potenziale, che andrebbero sviluppate e inserite in una moderna politica su ciascuna tipologia di turismo
Fetal cardiac time intervals: validation of an automatic tool for beat-to-beat detection on fetal magnetocardiograms
No full textFetal magnetocardiography (fMCG) allows the
non-invasive registration of fetal cardiac activity. This
technique, combined with the use of independent component
analysis (ICA) for signal processing, allows reconstructing of
reliable fetal cardiac traces. Low noise fetal signals can be used
to evaluate fetal cardiac time intervals (fCTI), useful to
monitor fetal heart function. In this work we present a method
for the automatic detection of cardiac waves (ACWD); it was
validated on 45 fMCG data sets of normal fetuses with
gestational age from 22 to 37 weeks. The outcomes of the
automatic procedure were compared with those of a manual
procedure performed by three independent operators on
rhythm strips of 100 consecutive cardiac cycles for each data
set. Distances between the wave boundaries detected with the
two methods were statistically estimated using confidence
intervals: differences were always comparable to those that
could be obtained from different investigators’ estimates.
Statistical correlation between fCTI quantified with ACWD
and with a manual procedure was assessed using the
parametric two-tailed Pearson’s correlation test, significance
level at a = 0.01. The automatic procedure showed a
computation time decrease in the ratio of approximately 1:600 with respect to the manual procedure performed on the same number of beats
Independent component analysis and fetal magnetocardiography: a tool for the automatic classification of independent components
No full textFetal Magnetocardiography (fMCG) allows the
non-invasive recording of the weak magnetic field variations associated with the electrical activity of the fetal heart. We used Independent Component Analysis (ICA) for the separation of maternal and fetal signals from fMCG recordings. The identification of fetal components is essential to reconstruct fetal signals. In this work we present a tool for the automatic classification of independent components (ACCT). Its performances were assessed using 66 fMCG data sets of normal fetuses ranging between 22 and 37 weeks. ACCT, whose outcomes were compared with those manually obtained
by an expert investigator, showed to be an effective tool.
Moreover, ACCT implementation permitted the reconstruction of stable and reliable fetal traces in a completely automatic manner. The SNR of the obtained fetal signals was high, showing that this was a further step forward the use of fMCG in hospital settings
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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