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Architettura stateless con uso di Singularity per il porting degli applicativi WRF-4.1.5 e BOLAM
Get PDFViene proposta una tecnologia stateless per il porting dei prodotti della ricerca su piattaforme Infrastucture As A Service (IAAS), centrata sull'uso di container basati sulla tecnologia Singularity
Image study of Mesopotamian cylinder seals through texts: the Procrustes transformation applied to Correspondence Analysis results
Get PDFThe use of Textual Correspondence Analysis to investigate a corpus of iconographic compositions carved on Mesopotamian cylinder seals proved to be very useful to understand the peculiarities of the specimens from the points of view of geographic origin, typology and inner chronology. The presence of a relatively high number of rare forms in the data set – besides the hapax – led to think, however, that the extraction of the factors – so the outcomes of the analyses – could have been influenced heavily by them. For this reason, looking for an optimal composition and for the most effective encoding of the data set, a reduction of its rarest forms was performed to find the threshold which could allow to reconcile the need for keeping the useful encoded information with the best possible reduction of elements producing high inertia. Adopting the methodology known as Procrustes, the data table was thus progressively reduced, and each time investigated: the results so obtained were then used to reach a global assessment about how much each reduced data set could correspond to the optimized one
Quantitative approaches to sacred Roman spaces in southern coastal Latium
Get PDFThe present paper aims at studying Roman sanctuaries from the late 4th century BC to the early 4th century AD in southern coastal Latium, a region of crucial importance for the development of Roman religion. Quantitative GIS-based research was undertaken to study sacred spaces in their natural and cultural landscape context. A first research question concerned the role of good accessibility of sanctuaries as a factor, which could have influenced the choice of construction sites for villas. Further research focused on the visibility of sanctuaries in respect to other elements of the cultural landscape such as villas and roads. Cost-distance and viewshed analyses were undertaken to answer these questions. As the analyses are based on published and archived site data, several issues related to the use of legacy survey data had to be faced. Results show that the role of sanctuaries as factors of attraction might not have been extremely high. While a few major sanctuaries with extraordinary visibility conditions are situated in the study area, the overall trend does not confirm the choice of particularly visible spots as a general rule
Contesti, metodologie, strumenti per il patrimonio culturale. Il progetto Portale delle fonti per la storia della Repubblica italiana
Get PDFIl presente contributo affronta alcune questioni metodologiche, tecniche
e tecnologiche connesse alla progettazione e realizzazione del Portale
delle fonti per la storia della Repubblica italiana, iniziativa che nasce
come caso di studio all’interno del Progetto PON Beni e patrimonio
culturale: governare la progettazione, finanziato dall’Agenzia per la
Coesione Territoriale nell’ambito del “Programma Azione Coesione
Complementare al Programma Operativo Nazionale Governance e
Capacità Istituzionale 2014-2020”. Vengono presentati l’apparato
teorico e metodologico impiegato nella fase di analisi preliminare alla
costruzione di un modello di governance nuovo ed efficiente; una
panoramica ragionata del patrimonio archivistico delle Istituzioni
partner; le soluzioni metodologiche e tecniche messe a punto per la
gestione delle criticità evidenziate nel corso delle attività; i principali
criteri e le metodologie adottati nell’organizzazione dei contenuti del
Portale e nelle attività di carattere redazionale. Chiude il rapporto la
presentazione del Glossario, messo a punto per orientare efficacemente
l’utenza nell’esplorazione dei contenuti
Case for setting up a 10 ps challenge: A step toward reconstruction-less TOF-PET
Get PDFThe future generation of radiation detectors is more and more demanding on timing performance for a wide range of applications, such as particle identification in nuclear physics and high-energy physics detectors, high-resolution
hadronic calorimetry in finely segmented detectors, precise event time tagging in high-luminosity accelerators, time-of-flight (TOF) techniques for PET cameras and a number of photonic applications based on single photon detection. There is in particular a consensus for gathering Europe’s multidisciplinary academic and industrial excellence around the ambitious challenge to develop a 10 ps TOF PET scanner (TOFPET). The goal is to reduce the radiation dose (currently 5–25 mSv
for whole-body PET/CT), scan time (currently >10 minutes), and costs per patient (currently >1000 e per scan), all by an order of magnitude. To achieve this very ambitious goal it is essential to significantly improve the performance of each component of the detection chain: light production, light transport, photodetection, readout electronics. Speeding up progress in this direction is the goal of the challenge and will have an important impact on the development of a new generation of ionization radiation detectors. It will be shown that the possibility to reach 10 ps time-of-flight resolution at small energies, as required in finely granulated calorimeters and PET scanners, although extremely challenging, is not limited by physical barriers and that a number of disruptive technologies, such as multifunctional heterostructures, combining the high stopping power of well-known scintillators with the ultrafast photon emission resulting from the 1D, 2D or 3D quantum confinement of the excitons in nanocrystals, photonic crystals, photonic fibers, as well as new concepts of 3D digital SiPM structures, pave the way to new radiation detector concepts with unprecedented performance
US/TOF-PET endorectal probe compatible with MR, for diagnosis and staging of the prostate cancer
Get PDFProstate Cancer (PCa) is one of the most prevalent cancers worldwide. Early and accurate diagnosis of PCa is crucial for effective and successful treatment. Our project aims at developing a unique, highly performing flexible
geometry multi-modality imaging system for diagnosis and staging of PCa. The imager will have the form of an endorectal probe combining high-resolution (0.1 mm)
ultrasound (US) with a very high-resolution Positron Emission Tomography (PET) probe (1 mm spatial resolution) with exceptional Time-of-Flight (TOF) capability (100 ps FWHM targeted) compatible with Magnetic Resonance Imaging (MRI), in coincidence with a set of external PET panels. While standard multiparametric MRI (mpMR) has drawbacks, diagnosis will be improved significantly by the introduction of PSPMA-PET as well as the simultaneous PET/MR imaging. The system will be capable of morphological visualization instantly and continuously combined with biological and metabolic activity, offering crucial improvement with respect to standard systems (detection of ∼ 2 mm lesions vs. ∼ 6 mm lesions) in spatial resolution, efficiency, signal-to-noise ratio (SNR), scanning time and/or lowering injected dose
New model-dependent analyses including DAMA/LIBRA–phase2
No full textThe first DAMA/LIBRA–phase2 model-independent results (exposure: 1.13 ton × yr, and software energy threshold at 1 keV) have recently been released. They further confirm —with high confidence level— the evidence already observed by DAMA/NaI and DAMA/LIBRA–phase1 on the basis of the exploited model-independent Dark Matter (DM) annual modulation signature. The total exposure above 2 keV of the three experiments is 2.46 ton × yr. Several DM candidate particles and related scenarios have been analyzed including the latest results. These analyses permit to constrain the parameters’ space of the considered candidates in the given scenarios, restricting their values with respect to previous analyses thanks to the increased exposure and to the lower energy threshold
The ATLAS tracking system for HL-LHC
No full textThe current inner detector of the ATLAS experiment will be replaced with a new, all-silicon detector to cope with the tough environment of the High Luminosity LHC (HL-LHC). The instantaneous luminosity of HL-LHC would result in harder conditions for the detector: increase in occupancy, bandwidth and radiation damage. The Inner Tracker (ITk) will consist of an inner pixel and outer strip detector aiming to provide tracking coverage up to |η| = 4. The layout of the pixel detector is now finalized with five layers of pixel silicon sensor modules in the central region and several ring-shaped layers in the forward region. Due to their radiation hardness, 3D sensors are a promising option for the innermost pixel layer while in the other layers planar sensors will be used. The required very high hit-rate capabilities, increased pixel granularity, extreme radiation hardness and reduced
material budget call for a size reduction as compared to existing sensors, involving smaller pitch, reduced active thickness and lower power consumption. All hybrid detector modules will be read out by a new front-end chip, developed within the RD53 Collaboration, connected to the silicon sensors using bump bonding. From simulations, the ITk performance in terms of tracking and vertexing is expected to be similar or better than that of the current tracking system, despite being in a much harsher environment
Search for lepton number violation and other exotic processes at NA62
No full textNA62 is a fixed target experiment at CERN, with the main goal of measuring the branching ratio of the very rare decay K+ → π+νν¯. However, the wide physics program covered by the experiment allows the search for other possible indications of new physics beyond the Standard Model. In this document,
the searches for lepton number violation and invisible vector bosons (“dark photon”) are reporte
Investigating two heavy neutral leptons neutrino seesaw mechanism at SHiP
No full textOne of the main purposes of the SHiP experiment is to shed light on neutrino mass generation mechanisms like the so-called seesaw one. We consider a minimal type-I seesaw neutrino mass mechanism model with two heavy neutral
leptons (right-handed or sterile neutrinos) with arbitrary masses. The extremely high active-sterile mixing angle requires a correlation between the phases of the Dirac neutrino couplings. Actual experimental limits on the half-life of neutrinoless double beta decay 0νββ-rate on the active-sterile mixing angle are not significative for SHiP