1,721,214 research outputs found
Signal Spectrum Analysis and Period Estimation by Using Delayed Signal Sampling
No full textThe paper describes a signal power spectrum analyzer and a signal period estimator whose bandwidth is not limited by the mean sampling time. The procedure relies on the evaluation of the input signal autocorrelation function in different delayed
time instants, located at either equispaced or random time instants.
To do this, a recursive random sampling process in the time domain was used in order to avoid any bandwidth limitation due
to the sampling strategy in the evaluation of each autocorrelation function. The signal power spectrum as well as its period, provided that an approximate value of the fundamental frequency is known, can finally be evaluated. Some theoretical background and experimental work are reported in the paper for validating the performance of the method
Biostratigrafia. In: Allegato al Foglio 256 Rimini della Carta Geologica D'Italia - Geologia di sottosuolo
No full textBiostratigrafia. In: Carta Geologica D'Italia - Foglio 256, Rimini della carta 1:50.000 dell'I.G.M.
No full textFirst report of a polychelid lobster (Crustacea: Decapoda: Coleiidae) from the Early Cretaceous of Italy
No full textWe report Coleia appenninica n. sp. (Coleiidae Van Straelen, 1925) discovered inside a concretion from Calderino, Northern Apennines (Bologna, Emilia Romagna, N Italy). In this area, blocks and rare concretions are present from the Lower and Upper Cretaceous, coming from the washing away of clays of the “Argille Varicolori del Samoggia unit” (AVS). The discovery of this species is exceptional not only for the rarity of fossils inside these blocks, but also because it extends the stratigraphical range for the genus to, at least, the Early Cretaceous. Coleia appenninica n. sp. represents the third unambiguous record of a Cretaceous polychelid decapod in the Tethyans realm
Coleia Appeninica, un raro Crostaceo di circa 100 milioni di anni rinvenuto nei calanchi del Bolognese
No full textDescriviamo il ritrovamento di Coleia appenninica n.sp. (Coleidae VAN STRAELEN, 1925) scoperto all’interno di una concrezione a Calderino, nell'Appennino settentri (Bologna, Emilia Romagna, N Italia). In quest’area sono presenti blocchi e concrezioni del Cretaceo Inferiore e Superiore, provenienti dalla dilavazione dei clasti delle “Argille Varicolari dell’unità del Samoggia” (AVS). La scoperta di questa specie è eccezionale, non solo per la rarità dei fossili in questi blocchi, ma anche perché estende il range stratigrafico della specie almeno al Cretaceo Inferiore. Coleia appenninica n.sp rappresenta il terzo ritrovamento inconfutabile di un decapode polichelide del Cretaceo nel dominio della Tetide Alpin
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
Towards a Power Production from 100% Renewables: The Italian Case Study
Full text linkThe need to reduce greenhouse gas emissions is driving many actions to decarbonize the most impactful sectors. Among these, the energy sector accounts for almost one third of emissions. Increasing the penetration of renewable energy in the energy mix could easily reduce the emissions of this sector. Theoretically, the target to aim for would be 100% renewable energy production. However, the variable nature of power production from photovoltaic and wind systems, which are expected to play a key role in the energy transition, may pose several limitations to the effective penetration of renewable energy. Many concerns arise when one considers the large diffusion of renewable energy that would be required to meet green targets, and the operating conditions of other systems in charge of compensating for renewable energy variations. This study aims to investigate the potential impact of an increase in the amount of renewable energy installed in a country, particularly in Italy. A simplified approach has been used, based on the assumption of knowing the hourly demand and power generation mix, and multiplying the intermittent power generation by a certain factor. Although not accurate, this approach allows the authors to highlight some critical aspects regarding the potential surplus of renewable energy and the operating conditions of other energy sources. The results of this study may provide a useful basis for a preliminary system evaluation, in particular to assess the feasibility of surplus recovery and the operability of residual generation systems. In addition, it may be easily replicated in other countries for similar estimations
The Meeting on the Plio-Pleistocene Boundary and thelower/middle Pleistocene transition: type areas andsections (Bari, 25-29 September 2000).
No full textFirst description of theropod remains from the Middle Jurassic (Bathonian) of Madagascar.
No full textNew theropod remains from the Middle Jurassic (Bathonian) of NW Madagascar are described that include 49 isolated teeth and a dorsal vertebra. Being referable to at least three taxa, they provide a first insight into the high morphological biodiversity in the Middle Jurassic theropods. They may represent the oldest Gondwanan material referable to the Abelisauridae and Coelurosauria found up to today; however, lacking more exhaustive data on theropod dentition, their affinities remain uncertain pending more complete material. Riassunto-Prima descrizione di resti di teropodi provenienti dal Giurassico medio (Bathoniano) del Madagascar
- …
