1,278 research outputs found
Ancora sul momento quarto della differenza media di Gini
No full textLa differenza media è stata introdotta nella metodologia statistica da C. Gini nel 1912 come misura della variabilità intesa come disuguaglianza tra le osservazioni, in alternativa agli indici di variabilità intesi come dispersione delle osservazioni intorno alla media.
Il momento quarto è stato ricavato per il modello normale nei lavori di Kamat (1960 e 1961) e di Nabeya (1961) e per il modello esponenziale in Girone (1968 a) e congetturato per il modello rettangolare da Girone (1968 b e c).
Scopo di questo lavoro è quello di puntualizzare la formula generale del momento quarto campionario della differenza media, nonché di calcolare tale momento per altri importanti modelli distributivi.
Il momento quarto, come è noto, consente di valutare la disnormalità di una distribuzione. Tale conoscenza è utile per valutare la convergenza alla normalità della distribuzione campionaria della differenza media
The Pleistocene bathyal teleostean fauna of Archi (Southern Italy): palaeoecological and palaeobiogeographic implications
No full textThe early-middle Pleistocene teleostean fauna of the Archi section, cropping out along the Calabrian side of the Messina Straits was studied. The integrated approach, based on the palaeobathymetric method coupled with the palaeoecological approach, already used on deep circalittoral and epibathyal assemblages, was applied for the palaeoenvironmental reconstruction. The otolith benthic and benthopelagic associations, strongly bathyal in their composition, suggest a deep bathyal palaeoenvironment, 500 to 1000 m deep, which is in agreement with the invertebrate benthic faunas. Compositional, structural, and taxonomical features of the teleostean assemblages indicate clearly Atlantic or more generally oceanic affinities. The Archi teleostean fauna indicates a palaeoceanographic pattern with deep-water and near-bottom temperature lower than 8-10°C, quite different from the Recent Mediterranean
Fish otoliths from the Pliocene Heraklion Basin (Crete Island, Eastern Mediterranean)
No full textThe Pliocene Eastern Mediterranean fish record is revealed through the study of a 60-m thick stratigraphic sequence near the village Voutes (Heraklion, Crete). Forty-two species belonging to twenty families are identified. Calcareous nannoplankton biostratigraphy places the studied sequence within the biozone MNN16a (latest Zanclean). The stratigraphic distribution of 31species is modified. Among these, 12species are reported for the first time in the Eastern Mediterranean Zanclean, while 19species are first reported outside the Ionian Sea. The Voutes fish fauna presents a diversified benthic and benthopelagic assemblage filling a significant gap in the fossil recor
Coryphaenoides biobtusus Lin & Brzobohatý & Nolf & Girone 2017, sp. nov.
No full text<i>Coryphaenoides biobtusus</i> sp. nov. <p>urn:lsid:zoobank.org:act: 58E20EDF-1778-4704-924E-886C4028B5A1</p> <p>Fig. 8 E–F</p> Diagnosis <p>This species is characterised by nearly rectangular and thickset otoliths. The anterior rim of the otoliths is blunt, which makes the highest part of the otolith at the anterior portion. The dorsal rim undulates, with the middle part being concave, while both the anterior and posterior parts are higher and angular. The posterior rim is rounded, smaller than the anterior one. The sulcus is filled with two large elongate collicula.</p> Etymology <p> The species epithet is derived from the Latin ‘ <i>biobtusus</i>, <i>a</i>, <i>um</i> ’, which means obtuse (or blunt) on both sides, alluding to the blunt anterior and posterior rims of the otoliths.</p> Type material examined <p> <b>Holotype</b></p> <p>ITALY: a left otolith (IRSNB P 9684, Fig. 8 E).</p> <p> <b>Paratype</b></p> <p>ITALY: 1 specimen (IRSNB P 9685, Fig. 8F).</p> Type locality and horizon <p>ITALY: Tortonian Clay at Alba, Tanaro River (massive clays, 5 m upstream of reference sandstone ledge).</p> Dimensions of the holotype <p>Length = 4.95 mm, height = 3.05 mm, thickness = 1.35 mm.</p> Description <p>The otoliths are very thick. The inner face is slightly convex; the outer face is markedly convex in all directions, but with the strongest convexity in the antero-posterior direction (Fig. 8E 1). The anterior rim of the otolith is oblique, bears a blunt rostrum, and slightly protrudes in its ventral part; the posterior rim is blunt and shorter than the anterior one. The ventral rim is smooth, curving gently upwards in its posterior portion. The sulcus is pince-nez-shaped (pince-nez is a kind of glasses without ear branches that are worn by pinching the nose), rather shallow, and with unclear ends at both the anterior and the posterior ends. The cristae are well-marked. The collicula are large, highly elevated, nearly rectangular in shape, and lie symmetrical to the junction between ostium and cauda. The dorsal area is narrower than the ventral one. A deep ventral furrow running along the ventral rim is especially evident in the paratype.</p> Remarks <p> These two well-preserved otoliths represent adult specimens of this species, which allow a reasonable assignment to the genus <i>Coryphaenoides</i> Gunnerus, 1765. In some Recent species, for example in <i>C</i>. <i>armatus</i> (Hector, 1875) (see Nolf 2013: pl. 92), the general outline of the otolith and the sulcus configuration are comparable to that of this fossil species.</p>Published as part of <i>Lin, Chien-Hsiang, Brzobohatý, Rostislav, Nolf, Dirk & Girone, Angela, 2017, Tortonian teleost otoliths from northern Italy: taxonomic synthesis and stratigraphic significance, pp. 1-44 in European Journal of Taxonomy 322</i> on pages 5-10, DOI: 10.5852/ejt.2017.322, <a href="http://zenodo.org/record/3829305">http://zenodo.org/record/3829305</a>
Some Early Estimates of the Impact of Covid-19 Pandemic on Apulian Tourism Sector in 2020
No full textDue to its strategic position on the cruise routes across the Mediterranean Sea and the
around 800 kilometres of coastline, Puglia is one of the most attractive regions in Italy, providing
for a variety of artistic sets such as museums, castles, churches, and this heritage, combined with
natural and archaeological sites, attracts millions of people every year, producing a huge income.
Starting from 2019-2018 data comparisons, the aim of the work is to focus on the impact of Covid-
19 pandemic on tourism sector and to produce some early reflexions on its evolution in 2020. It is
interesting to understand how tourist flows have changed and how this can influence economy.
The regional tourism agency Pugliapromozione is the primary data source; regarding forecasts,
ISTAT and ENIT are the sources for the national scenario, and SRM for Puglia and South of Italy.
Up to the first 10 months of 2019, nights spent by international tourists in Italy were over 360
million (+4.4% compared to 2018) and brought revenues of about 40 billion (+ 6.6%). The number
of travellers has also increased about 2.2% compared to 2018 and all these numbers describe a very
favourable trend for Italian tourism. Regarding Puglia, tourism is a driver for regional GDP, with a
significant increase of 6%, mostly due to 1.2 million visitors from abroad (+ 11.5% compared to
2018).
About 2020, although three scenarios have been predicted, the results of the one forecasting a rapid
recovery is considered, as it seems the most realistic. The model assumptions are:
1) safeguarding of the summer season and enhancement of the psychological factor based on the
need to travel;
2) positive effects of the national and regional tourism governance policy providing for the
extension of summer season up to October;
3) policies to support national tourism demand with financial aids to families (“holiday bonus”);
4) attractive pricing policies by tourism firms.
The model estimates a 10% drop in tourism demand, corresponding to over 1.5 million visitors less,
and the appreciable recovery signs are mostly due to domestic tourism.
Moreover, a different tourism behaviour has been imposing, triggering new opportunities: tourism
offer reorganized over long term, investments in sustainability and synergy among culture and
territories. Puglia has lots of places so far little visited which, avoided by mass tourism, have kept
their own authenticity and it can bring added value in the next tourist destinations
Surface response-based performance assessment of a virtual-flowmeter based transducer for helium monitoring
No full textThe assessment of the metrological performance of a virtual flowmeter-based transducer for helium under cryogenic conditions is proposed. At this aim, first a model of the transducer, mainly based on a virtual flowmeter exploiting Sereg-Schlumberger method and a valve model exploiting finite-element approach, is presented. The transducer and valve models are validated experimentally on a case study for helium monitoring in cryogenic systems at the European Organization for Nuclear Research (CERN). Then, a fully simulated approach is performed in order to assess the transducer performance. In particular, the analysis effort is optimized by systematically exploring operating conditions by means of 3d-CCRD strategy
Paleobathymetric interpretation of the fish otoliths from the Lower - Middle Quaternary deposits of Kephallonia and Zakynthos islands (Ionian Sea, Western Greece)
No full textFish otoliths arc herein used to estimate the depositional depth of the Early - Middle Pleistocene deposits at SE Zakynthos and SW Kephallonia Islands (Ionian Sea, Western Greece), through comparison with the modern bathymetric distributions of the identified fish taxa. These estimates provide a more detailed picture of the depth variations for the Gelasian - Ionian stage interval in the study areas. The Lower Pleistocene marine deposits of the Gerakas Formation (SE Zakynthos Island, Ionian Sea) were deposited at average depths of 400-450 meters, with eustacy playing an important role in the depth variability, between 1.95-1.73 Ma. An uplifting episode, followed by subsidence takes place between 1.73-1.66 Ma, taking the area to 200-300 meters of depth, and then back to 400-500 meters. However, the area seems uplifted again to 200-400 meters later on in the Calabrian stage (1.25-0.97 Ma). Sedimentation of the Akrotiri deposits (NW Kephallonia Island, Ionian Sea), during the same chronostratigraphic interval, took place in a similar setting. At the Early Pleistocene (1.95-1.73 Ma) this basin reached depths of 400-450 meters, with uplift and following subsidence taking place between 1.73-1.66 Ma. Overall, the application of fish otolith paleobathymetry in the study areas provide a detailed picture of the depth variations for the Early Quaternary interval and refine the currently hypothesized pattern of tectonic movements
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