360 research outputs found
FIRST AMPHIBIAN FIND IN EARLY PERMIAN FROM SARDINIA (ITALY)
An amphibian fauna from Permo-Carboniferous boundary beds is recorded for the first time in Italy. A thin fossiliferous level has been found in the Perdasdefogu Basin in southeastern Sardinia;it yields several speciments of Branchiosaurus cf."B." petrolei Gaudry 1875), often in mass mortality assemblages.Repeated mass mortality events testify to sudden changes in the environment of the basin, possibly due to seasonal variations. The finding of speciments very close to Branchiosaurus petrolei,which is a common species in the Central France basins,confirms that Sardinia at the time belonged to the same hydrographic basin of continental Europe, with no seaway in between.Furthermore, though not the primary focus of this note, we report the first discovery of the xenacanth teeth and acanthodian spines in Italy.  
Power Management Circuits for Low-Power RF Energy Harvesters
The paper describes the design and implementation of power management circuits for
RF energy harvesters suitable for integration in wireless sensor nodes. In particular, we report the
power management circuits used to provide the voltage supply of an integrated temperature sensor
with analog-to-digital converter. A DC-DC boost converter is used to transfer efficiently the energy
harvested from a generic radio-frequency rectifier into a charge reservoir, whereas a linear regulator
scales the voltage supply to a suitable value for a sensing and conversion circuit. Implemented in
a 65 nm CMOS technology, the power management system achieves a measured overall efficiency
of 20%, with an available power of 4.5 μW at the DC-DC converter input. The system can sustain
a temperature measurement rate of one sample/s with an RF input power of −28 dBm, making it
compatible with the power levels available in generic outdoor environments
Thermal boundary resistance from transient nanocalorimetry: a multiscale modeling approach
The Thermal Boundary Resistance at the interface between a nanosized Al film
and an Al_{2}O_{3} substrate is investigated at an atomistic level. A room
temperature value of 1.4 m^{2}K/GW is found. The thermal dynamics occurring in
time-resolved thermo-reflectance experiments is then modelled via macro-physics
equations upon insertion of the materials parameters obtained from atomistic
simulations. Electrons and phonons non-equilibrium and spatio-temporal
temperatures inhomo- geneities are found to persist up to the nanosecond time
scale. These results question the validity of the commonly adopted lumped
thermal capacitance model in interpreting transient nanocalorimetry
experiments. The strategy adopted in the literature to extract the Thermal
Boundary Resistance from transient reflectivity traces is revised at the light
of the present findings. The results are of relevance beyond the specific
system, the physical picture being general and readily extendable to other
heterojunctions.Comment: 12 pages, 8 figure
Mapping Habitat Quality in the Lombardy Region, Italy
This paper reports a case study which examines the how mapping ecosystem services can
be used to identify areas of significant natural value to be protected or restored. We
mapped habitat quality in Lombardy (northwest Italy) using the InVEST (Integrated
Valuation of Ecosystem Services and Tradeoff) model. Model outputs were used to
approximate the spatial distribution of ecological quality across the region provided a
framework to support the implementation of the Lombardy Regional Landscape Plan. This
resulted in a proposal for introduction of new protected areas in the updated Landscape
Plan, while other areas were proposed to be removed
A Low-Power Sigma-Delta Modulator for Healthcare and Medical Diagnostic Applications
This paper presents a switched-capacitor Sigma-Delta modulator designed in 90-nm CMOS technology, operating at 1.2-V supply voltage. The modulator targets healthcare and medical diagnostic applications where the readout of small-bandwidth signals is required. The design of the proposed A/D converter was optimized to achieve the minimum power consumption and area. A remarkable performance improvement is obtained through the integration of a low-noise amplifier with modified Miller compensation and rail-to-rail output stage. The manuscript also presents a set of design equations, from the small-signal analysis of the amplifier, for an easy design of the modulator in different technology nodes. The Sigma-Delta converter achieves a measured 96-dB dynamic range, over a 250-Hz signal bandwidth, with an oversampling ratio of 500. The power consumption is 30 μW, with a silicon area of 0.39 mm²
Performance‐Based Planning to Reduce Flooding Vulnerability. Insights from the Case of Turin (North‐West Italy)
Climate change is impacting urban areas with greater frequency and exposing continental cities located on floodplains to extreme short-duration rainfall events (cloudbursts). This scenario requires the development of site-specific flooding vulnerability mitigation strategies that improve local knowledge of flood-prone areas at the urban scale and supersede the traditional hazard approach based on the classification of riverine buffers with a predicted return-period. Moreover, decision-makers need to adopt performance-based strategies for contrasting climate changes and increasing the resilience of territories based on spatially explicit vulnerability assessment.
The research develops and tests the recent Flooding Risk Mitigation model of InVEST (Integrated Evaluation of Ecosystem Services and Trade-off) created by the Natural Capital Project where cloudburst vulnerability is the result of interaction between land use and soil hydrological conductivity. It is based on the assumption that during cloudburst events all saturated soils have the potential for flooding which creates water streams regardless of the distance to rivers or channels, causing damage and in the worst cases victims among the population.
The output of the model gives the run-off retention index evaluated in the catchment area of Turin (Italy) and its neighbourhoods. We evaluated the output to gain specific insight on potential land use adaptation strategies. The index is the first experimental GIS biophysical assessment developed in this area and it can prove useful in the revision process of the General Town Plan underway
L’analisi del microclima urbano a supporto della valutazione delle trasformazioni urbane. Primi esiti di una ricerca per migliorare la vivibilità della città di Milano
più intensi e frequenti rendendo le città e i territori contemporanei più fragili e vulnerabili. Tali effetti hanno un’incidenza
maggiore nei contesti fortemente urbanizzati dove le componenti ecosistemiche risultano più compromesse o degradate;
inoltre il crescente aumento della popolazione che vive nelle città espone sempre più persone a condizioni di stress e disagio
con ripercussioni sul benessere della collettività e la vivibilità urbana. L’incremento delle temperature nelle aree urbane, e la
conseguente insorgenza del fenomeno dell’isola di calore, dovuto a un elevato livello di impermeabilizzazione del suolo e a
una ridotta disponibilità di aree verdi e corsi/specchi d’acqua, è uno dei principali impatti derivanti dal cambiamento climatico
che affliggono le aree urbane con importanti conseguenze sul comfort termico e sulla salute dei cittadini.
La riduzione e mitigazione degli impatti dell’isola di calore rappresenta uno dei Servizi Ecosistemici di maggiore importanza
nella pianificazione urbana per la definizione di parametri e criteri di progettazione (anche di tipo Nature-based), sia per le aree
di nuova trasformazione che per la città esistente, volti al miglioramento delle performance urbane.
Il presente contributo propone una riflessione a partire dalla mappatura e valutazione del servizio ecosistemico di Urban Cooling
a cui associare un’analisi morfologica della città di Milano con l’obiettivo di verificare quali siano i parametri urbanistici
maggiormente performanti nel mitigare l’isola di calore e quindi da considerare nella progettazione degli spazi pubblici
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