2,226 research outputs found
Dual-Band Integrated Antennas for DVB-T Receivers
An overview on compact Planar Inverted-F Antennas (PIFAs) that are suitable for monitor-equipped devices is presented. In particular, high efficiency PIFAs (without any dielectric layer) with a percentage bandwidth (%BW) greater than 59% (470–862 MHz DVB-T band) are considered. In this context, two PIFA configurations are reviewed, where a dual-band feature has been obtained, in the 3300–3800 MHz (14% percentage bandwidth) WiMAX and 2400–2484 MHz (2.7% percentage bandwidth) WLAN IEEE 802.11b,g frequency bands, respectively, to also guarantee web access to on-demand services. The two PIFAs fill an overall volume of mm3 and mm3, respectively. They are composed of a series of branches, properly dimensioned and separated to generate the required resonances. Finally, to show the extreme flexibility of the previous two configurations, a novel dual-band L-shape PIFA has been designed. A reflection coefficient less than −6 dB and −10 dB and an antenna gain of around 2 dBi and 6.3 dBi have been obtained in the 470–862 MHz DVB-T band and the 2400–2484 MHz WLAN band, respectively. The L-shape PIFA prototype can be obtained by properly cutting and folding a single metal sheet, thus resulting in a relatively low-cost and mechanically robust antenna configuration
Improvement of a coastal vulnerability index and its application along the Calabria Coastline, Italy
The present paper further develops a coastal vulnerability index formulation (CVI) previously proposed by the authors by integrating a new variable and redefining three variables to improve the suitability of the index for low-lying coasts. Eleven variables are divided into three typological groups: geological, hydro-physical process and vegetation. The geological variables are: geomorphology, shoreline erosion/accretion rates, coastal slope, emerged beach width, and dune. The hydro-physical process group includes: river discharge, sea-level change, mean significant wave height and mean tide range. The vegetation variables are: vegetation behind the back-beach and coverage of Posidonia oceanica. The index was applied to a stretch of the Ionian coast in the province of Crotone in the Calabria region (Southern Italy), and a vulnerability map was produced. A geography information system (GIS) platform was used to better process the data. For the case study area, the most influential variables are shoreline erosion/accretion rates, coastal slope, emerged beach width, dune, vegetation behind the back-beach, and coverage of Posidonia oceanica. The most vulnerable transects are those near urban areas characterized by the absence of dunes and vegetation. Statistical and sensitivity analyses were performed, and the proposed CVI was compared with the previous formulation proposed by the authors and with two other CVI methods present in the literature
Design and test of the Digital Opto Hybrid Module for the CMS Tracker Inner Barrel and Disks.
One of the most important tasks to be performed in the CMS Tracker detector is the communication between hundreds of silicon modules and the central Control System under the supervision of the Data Acquisition System. To manage such complexity, modules are grouped in a hierarchical structure. Each group is controlled by a Communication and Control Unit (CCU). Several CCU form a ring with a Front End Controller as master. The entire Tracker Inner Barrel and Disks detector contains roughly 100 such rings called Control Rings. A description is given here of the implemented ring architecture for the detector and of the solutions found to provide a reliable and easy way to interconnect these groups
Formulation and assessment of Wash-Primer containing lanthanum tannate for steel temporary protection
Tannins are polyphenols synthesized by plants and useful for the coating industry as corrosion inhibitors. In addition, lanthanum salts have a great inhibitory effect on steel corrosion. The aim of this study was to obtain lanthanum ‘‘tannate’’ with adequate solubility to be incorporated as the corrosion inhibitor in a wash-primer. The ‘‘tannate’’ was obtained from commercial ‘‘Quebracho’’ tannin and 0.1 M La(NO3)3. The soluble tannin was determined by the Folin–Denis reagent, while the concentration of Lanthanum was obtained by a gravimetric procedure. The protective action of ‘‘tannate’’ on SAE 1010 steel was evaluated by linear polarization curves and corrosion potential measurements. Lanthanum ‘‘tannate’’ was incorporated in a wash-primer formulation and tested by corrosion potential and ionic resistance measurements. The corrosion rate was also determined by the polarization resistance technique. Besides, the primer was incorporated in an alkyd paint system and its anticorrosion performance assessed in the salt spray cabinet and by electrochemical impedance spectroscopy. Results showed that lanthanum ‘‘tannate’’ primer inhibits the development of deleterious iron oxyhydroxides on the steel substrate and incorporated into a paint system had a similar behavior to the primer formulated with zinc tetroxychromate.Centro de Investigación y Desarrollo en Tecnología de Pintura
Formulation and assessment of Wash-Primer containing lanthanum tannate for steel temporary protection
Tannins are polyphenols synthesized by plants and useful for the coating industry as corrosion inhibitors. In addition, lanthanum salts have a great inhibitory effect on steel corrosion. The aim of this study was to obtain lanthanum ‘‘tannate’’ with adequate solubility to be incorporated as the corrosion inhibitor in a wash-primer. The ‘‘tannate’’ was obtained from commercial ‘‘Quebracho’’ tannin and 0.1 M La(NO3)3. The soluble tannin was determined by the Folin–Denis reagent, while the concentration of Lanthanum was obtained by a gravimetric procedure. The protective action of ‘‘tannate’’ on SAE 1010 steel was evaluated by linear polarization curves and corrosion potential measurements. Lanthanum ‘‘tannate’’ was incorporated in a wash-primer formulation and tested by corrosion potential and ionic resistance measurements. The corrosion rate was also determined by the polarization resistance technique. Besides, the primer was incorporated in an alkyd paint system and its anticorrosion performance assessed in the salt spray cabinet and by electrochemical impedance spectroscopy. Results showed that lanthanum ‘‘tannate’’ primer inhibits the development of deleterious iron oxyhydroxides on the steel substrate and incorporated into a paint system had a similar behavior to the primer formulated with zinc tetroxychromate.Centro de Investigación y Desarrollo en Tecnología de Pintura
ALKALINE HYDROTHERMAL STABILIZATION OF Cr(VI) IN A SANDY SOIL
Chromium (Cr) pollution of soil is a serious environmental problem, especially in industrialized areas. Risks
for human and environmental health are strictly connected to Cr oxidation state, which is usually trivalent
or hexavalent in soil. While Cr(III) is stable, scarcely mobile and weakly toxic, Cr(VI) is highly soluble,
mobile and carcinogenic. Among the different remediation strategies, stabilization/solidification (S/S) is
used as rapid and cost-effective technique for heavy metal polluted soils. It consists of the addition of
appropriate materials to the polluted soil, mostly under alkaline conditions, in order to chemically and/or
physically transform the contaminant in a stable and less toxic form. Waste materials like coal fly ash or
other cheap sources of Si and Al can be used to stabilize heavy metals in soil (Terzano et al., 2005).
This study aims at evaluating a new S/S process for the reduction of Cr(VI) to Cr(III) in polluted soils and
the incorporation of Cr(III) in newly formed minerals by using a reactive mixture of glass and aluminum
(recovered from solid municipal wastes) and an alkaline hydrothermal treatment
PROGETTO “MESSINA 1908 – 2008”. RAPPORTO DELLA CAMPAGNA OBS NELL’AREA EOLIANA E DELLO STRETTO DI MESSINA
Il Centro Nazionale Terremoti (CNT), in collaborazione con la sezione di Catania, ha progettato e
realizzato un esperimento di sismica passiva nell’area Calabro–Peloritana il cui scopo è fornire nuovi dati
sismici volti a comprendere come le dinamiche superficiali ed il processo di subduzione interagiscano tra
loro, migliorando così la comprensione dei processi sismogenetici nella zona colpita dal terremoto del 1908
[Margheriti et al., 2008; http://dpc-s5.rm.ingv.it].
Con l’obiettivo di ridurre l’errore di localizzazione degli ipocentri degli eventi verificatisi nell’area
interessata dal progetto, ad integrazione delle 30 stazioni della rete sismica nazionale già presenti nell’area in
esame, l’esperimento ha previsto l’installazione di 15 stazioni della rete mobile e la deposizione di 5 OBS/H
(Ocean Bottom Seismometer with Hydrophone), per un numero complessivo di 50 stazioni sismiche larga
banda 3C coinvolte nel progetto.
La campagna sismica a terra ha avuto inizio nell’ottobre 2007 e ad oggi (gennaio 2009), le stazioni
sono ancora in funzione, mentre la deposizione dei cinque OBS/H è avvenuta tra il 15 e il 18 luglio 2008 ed
il loro recupero è stato effettuato tra il 6 e il 7 novembre 2008.
Gli OBS/H, progettati e realizzati presso l’OBS Lab di Gibilmanna, sono stati equipaggiati con
sismometri Nanometrics Trillium 120p (120s - 175 Hz) e con sensori differenziali di pressione (Differential
Pressure Gauge) Cox-Webb, con banda passante tra i 200s e i 2Hz.
La base autolivellante sulla quale è installato il sensore sismico è stata realizzata anch’essa presso
l’OBS Lab di Gibilmanna nei mesi intercorsi tra il recupero degli OBS impiegati nella prima campagna
NERIES, avvenuto nel marzo 2008, e il luglio 2008, data della deposizione degli OBS del progetto “Messina
1908 – 2008”. La necessità di realizzare una nuova base autolivellante in tempi così brevi, è stata una diretta
conseguenza dei risultati negativi ottenuti dalla base Nautilus in occasione della già citata campagna
NERIES [D’Anna et al., 2008]: due sismometri su tre non si erano livellati nel range di ±0.2°, massimo tilt
dinamico previsto per i Trillium 120p, provocando il non funzionamento degli stessi. Come meglio verrà
analizzato nei paragrafi successivi, le problematiche affrontate nella realizzazione di questi dispositivi di
livellamento sono state molteplici e di difficile soluzione. L’analisi preliminare dei dati ha evidenziato che
soltanto uno dei cinque sensori sismici ha funzionato correttamente per l’intero periodo, mentre gli altri
quattro hanno funzionato in media per circa 20 giorni. Causa di ciò, un rapido consumo delle batterie dovuto
ad un livellamento sì compreso nel range di ±0.2° dall’orizzontale, condizione necessaria perché il
sismometro sia in grado di rilevare eventi sismici, ma oltre il range di ±0.1°, condizione necessaria perché i
consumi del Trillium120p si riducano da circa 2.5W ai 600mW nominali.
I risultati ottenuti da questo esperimento, sono comunque da inquadrare in una successione degli
eventi che ha fatto sì che lo sviluppo di questa nuova base autolivellante fosse condizionato da una certa
urgenza: al CNT premeva presentare i dati raccolti dagli OBS al convegno “Scienza e società a 100 anni dal
grande Terremoto”, che si sarebbe tenuto a Reggio Calabria dal 10 al 12 dicembre 2008 e visti gli insuccessi
della base Nautilus nel precedente esperimento, ci si è trovati di fronte alla necessità di progettare e
sviluppare un nuovo sistema di livellamento per i Trillium 120p nell’arco di tre mesi e mezzo. Queste, oltre a
quelle di natura economica, le ragioni per cui non è stato possibile procedere secondo un iter che per noi,
come per le aziende che operano nel settore marino, è uno standard:
- Progettazione;
- Realizzazione del prototipo;
- Test in laboratorio (e. g. tavola vibrante)
- Test in camera iperbarica;
- Test in mare;
- Produzione in serie;
E’ nostra intenzione, in un prossimo futuro, portare avanti lo sviluppo di questa base autolivellante,
con tempi e risorse finanziare ed umane più appropriate. Ciò che riportiamo in questo Rapporto Tecnico
vuole essere una descrizione del lavoro sin qui svolto, anche se non conclusivo e risolutivo, ma che ci ha già
permesso di individuare delle problematiche fondamentali la cui soluzione sarà oggetto di studi più
approfonditi. Rimane positivo il fatto che le basi già realizzate riescono già da adesso a livellare
automaticamente un sensore entro un range di ±0.2°.
Gli OBS/H dell’INGV verranno nuovamente deposti con la stessa disposizione del progetto “Messina
1908 – 2008” nell’estate 2009, nell’ambito del progetto S5 finanziato dal Dipartimento della Protezione Civile. Per sopperire alle problematiche riscontrate nella marinizzazione del Trillium 120p, si è scelto di
installare a bordo degli OBS dei sensori Guralp CMG40T-OBS (60s – 100 Hz), progettati per installazioni in
mare sino a profondità di 6000 m è già dotati di una propria base autolivellante. Il motivo per il quale non si
è utilizzato nelle passate campagne questo tipo di sensore è da addebitare unicamente al fatto che sui fondi
DPC della convenzione 2005-2007 non è stato possibile inserire l’acquisto di questi specifici sensori, mentre
erano disponibili i Trillium 120p
L’acteur et l’écoute augmentée: tissage sonore de voix autour des Bacchantes d’Euripide
This paper discusses the dynamic between digital tools and the actor’s ability to listen. It presents the results of the workshop Voices on Stage: An Approach to Ancient Greek Tragedy in the Digital Era (Athens, 2018) which confronts the actor to different layers of voice (direct, amplified, and synthetic). Through those experiments and their analysis, one will demonstrate how listening to synthetic voices can reinforce the actor’s sensibility to voice, stimulate his/her’s other senses and transform the act of listening into a tactile and visual experience.En s’appuyant sur une expérience pédagogique basée sur la confrontation des voix non-médiatisée, amplifiée et synthétisée, lors du workshop Voices On Stage : An Approach to Ancient Greek Tragedy in the Digital Era (Athènes, 2018), cet article propose une réflexion sur la relation entre les technologies digitales et l’écoute de l’acteur. Il s’agit de démontrer que l’écoute de voix de synthèse - souvent mise en opposition aux voix “naturelles” ou “organiques” - peut paradoxalement constituer pour l’acteur une façon de renforcer son rapport sensible à la voix et de stimuler ses sens autrement.En s’appuyant sur une expérience pédagogique basée sur la confrontation des voix non-médiatisée, amplifiée et synthétisée, lors du workshop Voices On Stage : An Approach to Ancient Greek Tragedy in the Digital Era (Athènes, 2018), cet article propose une réflexion sur la relation entre les technologies digitales et l’écoute de l’acteur. Il s’agit de démontrer que l’écoute de voix de synthèse - souvent mise en opposition aux voix “naturelles” ou “organiques” - peut paradoxalement constituer pour l’acteur une façon de renforcer son rapport sensible à la voix et de stimuler ses sens autrement.En s’appuyant sur une expérience pédagogique basée sur la confrontation des voix non-médiatisée, amplifiée et synthétisée, lors du workshop Voices On Stage : An Approach to Ancient Greek Tragedy in the Digital Era (Athènes, 2018), cet article propose une réflexion sur la relation entre les technologies digitales et l’écoute de l’acteur. Il s’agit de démontrer que l’écoute de voix de synthèse - souvent mise en opposition aux voix “naturelles” ou “organiques” - peut paradoxalement constituer pour l’acteur une façon de renforcer son rapport sensible à la voix et de stimuler ses sens autrement
Clinical, laboratory and ultrasonographic findings at baseline predict long-term outcome of polymyalgia rheumatica: a multicentric retrospective study : Polymyalgia rheumatica predicted by ultrasonographic findings polymyalgia rheumatica outcome predicted early by ultrasound
To assess the rate of PMR who, during the follow-up, undergo a diagnostic shift as well as to assess which clinical, laboratory and US findings are associated to a diagnostic shift and predict the long-term evolution of PMR. All PMR followed-up for at least 12 months were included. According to the US procedures performed at diagnosis, patients were subdivided into four subgroups. Clinical data from follow-up visits at 12, 24, 48 and 60 months, including a diagnostic shift, the number of relapses and immunosuppressive and steroid treatment, were recorded. A total of 201 patients were included. During the follow-up, up to 60% had a change in diagnosis. Bilateral LHBT was associated with persistence in PMR diagnosis, whereas GH synovitis and RF positivity to a diagnostic shift. Patients undergoing diagnostic shift had a higher frequency of GH synovitis, shoulder PD, higher CRP, WBC, PLT and Hb and longer time to achieve remission, while those maintaining diagnosis had bilateral exudative LHBT and SA-SD bursitis, higher ESR, lower Hb and shorter time to remission. Cluster analysis identified a subgroup of older patients, with lower CRP, WBC, PLT and Hb, lower PD signal or peripheral synovitis who had a higher persistence in PMR diagnosis, suffered from more flares and took more GCs. Most PMR have their diagnosis changed during follow-up. The early use of the US is associated with a lower dosage of GCs. Patients with a definite subset of clinical, laboratory and US findings seem to be more prone to maintain the diagnosis of PMR
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