1,757 research outputs found
Progress in the development of a S RETGEM-based detector for an early forest fire warning system
In this paper we present a prototype of a Strip Resistive Thick GEM
photosensitive gaseous detector filled with Ne and ethylferrocene vapours at a
total pressure of 1 atm for an early forest fire detection system. Tests show
that it is one hundred times more sensitive than the best commercial
ultraviolet flame detectors and therefore, it is able to reliably detect a
flame of 1.5x1.5x1.5 m3 at a distance of about 1km. An additional and unique
feature of this detector is its imaging capability, which in combination with
other techniques, may significantly reduce false fire alarms when operating in
an automatic mode.
Preliminary results conducted with air filled photosensitive gaseous
detectors are also presented. The approach main advantages include both the
simplicity of manufacturing and affordability of construction materials such as
plastics and glues specifically reducing detector production cost. The
sensitivity of these air filled detectors at certain conditions may be as high
as those filled with Ne and EF. Long term test results of such sealed detectors
indicate a significant progress in this direction.
We believe that our detectors utilized in addition to other flame and smoke
sensors will exceptionally increase the sensitivity of forest fire detection
systems. Our future efforts will be focused on attempts to commercialize such
detectors utilizing our aforementioned findings.Comment: Presented at the International Conference on Micropattern gaseous
detectors, Crete, Greece, June 200
The current progress of the ALICE Ring Imaging Cherenkov Detector
Recently, the last two modules (out of seven) of the ALICE High Momentum
Particle Identification detector (HMPID) were assembled and tested. The full
detector, after a pre-commissioning phase, has been installed in the
experimental area, inside the ALICE solenoid, at the end of September 2006. In
this paper we review the status of the ALICE/HMPID project and we present a
summary of the series production of the CsI photo-cathodes. We describe the key
features of the production procedure which ensures high quality photo-cathodes
as well as the results of the quality assessment performed by means of a
specially developed 2D scanner system able to produce a detailed map of the CsI
photo-current over the entire photo-cathode surface.
Finally we present our recent R&D efforts toward the development of a novel
generation of imaging Cherenkov detectors with the aim to identify, in heavy
ions collisions, hadrons up to 30 GeV/c.Comment: Presented at the Imaging-2006 Conference, Stockholm, Sweden, June
200
Le parole della crisi, le politiche dopo la pandemia. Guida non emergenziale al post-Covid-19
Lo scorso 11 marzo, l'Organizzazione Mondiale della SanitĂ ha dichiarato il Covid-19 una pandemia. Molti paesi hanno conseguentemente adottato o inasprito le misure di contenimento della mobilitĂ e la sospensione delle attivitĂ produttive. Inevitabilmente, la crisi ha coinvolto la sfera economica, quella sociale, il mondo culturale e l'ambito politico-istituzionale, in alcuni casi esacerbando tendenze che erano presenti in nuce nella trama delle relazioni intersoggettive, altre volte lacerando le aspettative, i valori e le percezioni sui quali ciascuno di noi, e la comunitĂ nel suo complesso, definisce e articola la propria esistenza.
Il CEST - Centro per l'Eccellenza e gli Studi Transdisciplinari, come associazione di studenti, dottorandi e giovani ricercatori, con diversi background, propone un volume che analizza, in chiave transdisciplinare, la pluralità dei possibili effetti dell'emergenza in corso e indica alcune linee direttrici per immaginare la sua gestione nei prossimi mesi, mediante un approccio specifico e originale: il libro è infatti il frutto della collaborazione tra giovani studiose e studiosi e figure autorevoli del dibattito culturale italiano e internazionale
The dominant seagrass herbivore Sarpa salpa shifts its shoaling and feeding strategies as they grow
The relative benefits of group foraging change as animals grow. Metabolic requirements, competitive abilities and predation risk are often allometric and influenced by group size. How individuals optimise costs and benefits as they grow can strongly influence consumption patterns. The shoaling fish Sarpa salpa is the principal herbivore of temperate Posidonia oceanica seagrass meadows. We used in-situ observations to describe how ontogeny influenced S. salpa individual feeding behaviour, shoaling behaviour and group foraging strategies, and its potential consequences to seagrass meadows. Shoaling was strongly influenced by body length: shoals were highly length-assorted and there was a clear positive relationship between body length and shoal size. Foraging strategies changed dramatically with shoal size. Small shoals foraged simultaneously and scattered over large areas. In contrast, larger shoals (made of larger individuals) employed a potentially cooperative strategy where individuals fed rotationally and focused in smaller areas for longer times (spot feeding). Thus, as individuals grew, they increased their potential impact as well, not merely because they consumed more, but because they formed larger shoals capable of considerably concentrating their grazing within the landscape. Our results indicate that ontogenetic shifts in group foraging strategies can have large ecosystem-wide consequences when the species is an important ecosystem modifier
The Integrated HV, LV and Liquid Radiator Control System for the HMPID in the ALICE Experiment at LHC
The complexity and the underground location of the new generation experiments (ALICE, ATLAS, CMS and LHCb) at the CERN Large Hadron Collider (LHC) requires a reliable and user friendly control system to operate such large detectors remotely. Control system experts at CERN are deeply involved in developing the JCOP (Joint Controls Project) 'Framework', a software running in the PVSSII SCADA1 (Supervisory Control And Data Acquisition) system, that will provide a homogeneous and ready to use tool for the control system developers of the LHC experiments. The High Momentum Particle Identification Detector (HMPID), one of the ALICE2 sub-detectors, is being equipped with a Detector Control System (DCS) developed within the JCOP Framework. In this paper the basic features and the first results of the DCS prototype are presented
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