INDAGINI TEORICHE E SPERIMENTALI SU PARETI SISMICHE IN ACCIAIO

La memoria riguarda il comportamento di pannelli sottili in acciaio utilizzati come pareti di controvento. Per tali sistemi sono previsti due tipi fondamentali di utilizzo: come elementi dissipativi e irrigidenti;come elementi irrigidenti. Il primo caso riguarda pannelli dotati di robusti irrigidimenti, tali da determinare lo snervamento delle lastre costituenti il pannello prima dell’insorgere di fenomeni di instabilità. Tale tipologia è stata utilizzata prevalentemente in Giappone. La tendenza ad adottare pannelli sottili, per i quali l’instabilità avviene in campo elastico, si è sviluppata prevalentemente negli USA ed in Canada, ove attraverso indagini sperimentali si è constatato il notevole contributo dovuto alle riserve in campo post critico dei pannelli. Anche i risultati sperimentali ottenuti dagli autori evidenziano le notevoli riserve di resistenza di tali pannelli in campo post-critico, cosicché oggi è ampliamente plausibile l’introduzione nel progetto di tali elementi strutturali soggetti ad instabilità per azioni sismiche modeste. Gli studi condotti dagli autori hanno riguardato il comportamento di tali pannelli sottili in acciaio sottoposti a forze orizzontali, sviluppando indagini teoriche e sperimentali. La sperimentazione effettuata conferma che in campo post-critico si attivano bande diagonali di trazione, rendendo le riserve di resistenza cospicue; tuttavia i modelli FEM, sviluppati in ambito non lineare, non consentono di riprodurre il comportamento del sistema nella fase iniziale del carico. Nella presente nota si riporta una sintesi delle indicazioni normative e dei risultati ottenuti dagli autori nelle precedenti esperienze, proponendo un chiave di lettura sintetica per prevedere il comportamento di tali sistemi

Bonding of the Inner Tracker Silicon Microstrip Modules

Microbonding of the CMS Tracker Inner Barrel (TIB) and Tracker Inner Disks (TID) modules was shared among six different Italian Institutes. The organization devised and the infrastructure deployed to handle this task is illustrated. Microbonding specifications and procedures for the different types of TIB and TID modules are given. The tooling specially designed and developed for these types of modules is described. Experience of production is presented. Attained production rates are given. An analysis of the microbonding quality achieved is presented, based on bond strengths measured in sample bond pull tests as well as on rates of bonding failures. Italian Bonding Centers routinely performed well above minimum specifications and a very low global introduced failure rate, at the strip level, of only $\sim$0.015 \% is observed

Predictive role of node-rads score in patients with prostate cancer candidates for radical prostatectomy with extended lymph node dissection: comparative analysis with validated nomograms

Background and objectives: The Reporting and Data System (RADS) have been used in the attempts to standardize the results of oncological scans in different scenarios, such as lymph nodes, adding configuration criteria to size determination. We analyze the predictive value of preoperative Node-RADS determination at imaging for pelvic lymph node (PLN) involvement in cases of prostate cancer (PC) considered for radical prostatectomy (RP) with extended lymph node dissection (eLND) and we compare it with validate predictive nomograms (MSKCC, Briganti and Gandaglia). Methods: 150 patients with a histological diagnosis of PC (high risk or intermediate with an estimated risk for pN+ higher than 5% using the Briganti or 7% using the Gandaglia nomogram) submitted for RP with an ePLND from 2018 and 2021 were retrospectively examined. Node-RADS determination was performed in all cases using the preoperative magnetic resonance (MR), performed by a radiologist blinded for pathologic results and compared with the MSKCC, Briganti 2012, Gandaglia 2017 and Gandaglia 2019 nomograms. Results: PLN involvement at final pathology (pN+) was found in 36/150 (24.0%) of cases and the mean percentage of positive LNs in pN+ cases was 15.90 ± 13.40. The mean number of PLNs removed at RP was similar (p = 0.188) between pN0 (23.9 ± 8.0) and pN+ (25.3 ± 8.0) cases. Considering a Node RADS 4-5 positive and a Node RADS 1-2 negative, the PPV was 100% and the NPV was 79.6%. A Node RADS score 4-5 showed a lower sensitivity (0.167 versus 0.972, 1.000, 0.971, 0.960 respectively), a higher specificity (1.000 versus 0.079, 0.096, 0.138, 0.186 respectively) and a similar AUC (0.583 versus 0.591, 0.581, 0.574, 0.597 respectively) when compared to MSKCC, Briganti 2012, Gandaglia 2017 and Gandaglia 2019 nomograms. Conclusions: Our evaluation suggests that Node RADS score, combining configuration criteria to size determination could improve specificity in terms of pathologic PLN prediction but a very low sensitivity has been also described

Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

Indagine sperimentale sul comportamento di pareti sismiche in acciaio sottoposte a taglio

The paper concerns the experimental results performed on steel (S 235) zinc plated panels having 1500 x 1150 x 1.5 mm dimensions, linked to hinged steel frame. In order to the slenderness of plates, considerable displacements out-of-plane are evident at loads significantly lower of ultimate load. Considering the steel constitutive curves obtained from tensile tests, the comparison of experimental and numerical (ADINA) results is proposed. The results show the excellent seismic behaviour of the system having stable hysteresis loops

COMPORTAMENTO CICLICO DI PANNELLI SOTTILI IN ACCIAIO

abstractitaLa memoria riporta i risultati di indagini sperimentali su pareti sottili in acciaio sottoposte ad azioni cicliche, ponendo in risalto le capacità dissipative. Le prove sono state condotte presso il laboratorio DISMAT di Canicattì (AG)su modelli in scala 1:2. I risultati evidenziano le riserve di resistenza dei pannelli in fase post critica.Results of experimental tests on Steel Plate Shear Wall (SPSW) placed in steel frames subjected to cyclic actions are presented, stressing the dissipative capacity of the system. The tests were performed at the DISMAT laboratory in Canicattì (AG) on scale specimens. The surrounding frame is made by HEA 160 beam and columns with pinned joint, and by SPSW of dimensions 1500 x 1150 mm connected to the surrounding frame by bolts; tests with several different thickness of SPSW were performed.. The experimental results show the large residual strength of the SPSW in the post-buckling phase and the dissipative efficiency is proved by evaluation of a meaningful response parameter of energetic derivation

Indagine sperimentale sul comportamento ciclico di pannelli sottili di controvento di telai in acciaio

The paper concerns the experimental results performed on steel (S 235) zinc plated panels having 1500 x 1150 x 1.5 mm dimensions, linked to hinged steel frame. In order to the slen-derness of plates, considerable displacements out-of-plane are evident at loads significantly lower of ultimate load. Considering the steel constitutive curves obtained from tensile tests, the comparison of experimental and numerical (ADINA) results is proposed. The results show the excellent seismic behaviour of the system having stable hysteresis loops