23 research outputs found

    Banco Tensore d'Inerzia

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    Nella presente relazione si descrive il Banco Tensore d'Inerzia realizzato presso il Dipartimento al fine di soddisfare la richiesta, avanzata in particolar modo dalle aziende del settore automotive, di disporre della misura dei parametri d'inerzia di interi veicoli o di suoi componenti. Dopo aver descritto il principio di funzionamento, si illustreranno le procedure di prova e le tecniche adottate per la calibrazione

    On the homogenization of periodic beam-like structures

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    Abstract A homogenization method for periodic beam-like structures that is based on the unit cell force transmission modes is presented. Its main advantage is that to identify the principal vectors of the state transfer matrix corresponding to the transmission modes it operates directly on the sub-partitions of the unit cell stiffness matrix and allows to overcome the problems due to ill-conditioning of the transfer matrix. As case study, the Pratt girder is considered. Closed form solutions for the transmission modes of this girder are achieved and used into homogenization. Since the pure bending mode shows that the Pratt unit cell transmits two kinds of bending moments, one given by the axial forces and the other originated by nodal moments, the Timoshenko couple-stress beam is employed as substitute continuum. Finally, a validation of the proposed procedure is carried out comparing the predictions of the homogenized models with the results of a series of girder f.e. analyses

    Transverse strength of railway tracks : Part 2. Test system for ballast resistance in line measurement

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    © Gruppo Italiano Frattura 2014. This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. See: https://creativecommons.org/licenses/by/4.0/In the present paper, testing methods currently adopted to measure the in service ballast resistance are synthetically reviewed to identify the main sources of uncertainty influencing the test loads and to define an experimental methodology allowing the optimal control of the testing parameters without the introduction of spurious or parasitic actions on the track sample. An alternative testing system, which allows applying on a full-scale sample of a railway track testing loads very close the real ones, is presented. Of the new system, both the ways of use for measuring the transversal and axial ballast strength, the general procedure to carry out the experimentation and its application to a real scenario are described, highlighting its main advantages in terms both of modalities for applying the loads and of testing parameter control.Peer reviewe

    Transverse strength of railway tracks : Part 3. Multiple scenarios test field

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    © Gruppo Italiano Frattura 2014. This is an Open Access article distributed in accordance with the terms of the Creative Commons Attribution (CC BY 4.0) license, which permits others to distribute, remix, adapt and build upon this work, for commercial use, provided the original work is properly cited. See: https://creativecommons.org/licenses/by/4.0/In the present paper the design and construction choices of a test field for the ballast lateral resistance measurement, in order to produce data useful for the development of a numerical model able to simulate the service critical conditions of a continuous welded rail track, are described. Some construction details described herein allow to better understand the methodological approach followed in the design of experiments, the tests management philosophy as well as of the accuracy achieved in their implementation.Peer reviewe

    Intra-and extra-hospitalization monitoring of vital signs. Two sides of the same coin. Perspectives from Lims and Greenline study operators

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    Background: In recent years, due to the epidemiological transition, the burden of very complex patients in hospital wards has increased. Telemedicine usage appears to be a potential high-impact factor in helping with patient management, allowing hospital personnel to assess conditions in out-of-hospital scenarios. Methods: To investigate the management of chronic patients during both hospitalization for disease and discharge, randomized studies (LIMS and Greenline-HT) are ongoing in the Internal Medicine Unit at ASL Roma 6 Castelli Hospital. The study endpoints are clinical outcomes (from a patient’s perspective). In this perspective paper, the main findings of these studies, from the operators’ point of view, are reported. Operator opinions were collected from structured and unstructured surveys conducted among the staff involved, and their main themes are reported in a narrative manner. Results: Telemonitoring appears to be linked to a reduction in side-events and side-effects, which represent some of most commons risk factors for re-hospitalization and for delayed discharge during hospitalization. The main perceived advantages are increased patient safety and the quick response in case of emergency. The main disadvantages are believed to be related to low patient compliance and an infrastructural lack of optimization. Conclusions: The evidence of wireless monitoring studies, combined with the analysis of activity data, suggests the need for a model of patient management that envisages an increase in the territory of structures capable of offering patients subacute care (the possibility of antibiotic treatments, blood transfusions, infusion support, and pain therapy) for the timely management of chronic patients in the terminal phase, for which treatment in acute wards must be guaranteed only for a limited time for the management of the acute phase of their diseases

    Proceedings of Abstracts Engineering and Computer Science Research Conference 2019

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    © 2019 The Author(s). This is an open-access work distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. For further details please see https://creativecommons.org/licenses/by/4.0/. Note: Keynote: Fluorescence visualisation to evaluate effectiveness of personal protective equipment for infection control is © 2019 Crown copyright and so is licensed under the Open Government Licence v3.0. Under this licence users are permitted to copy, publish, distribute and transmit the Information; adapt the Information; exploit the Information commercially and non-commercially for example, by combining it with other Information, or by including it in your own product or application. Where you do any of the above you must acknowledge the source of the Information in your product or application by including or linking to any attribution statement specified by the Information Provider(s) and, where possible, provide a link to this licence: http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/This book is the record of abstracts submitted and accepted for presentation at the Inaugural Engineering and Computer Science Research Conference held 17th April 2019 at the University of Hertfordshire, Hatfield, UK. This conference is a local event aiming at bringing together the research students, staff and eminent external guests to celebrate Engineering and Computer Science Research at the University of Hertfordshire. The ECS Research Conference aims to showcase the broad landscape of research taking place in the School of Engineering and Computer Science. The 2019 conference was articulated around three topical cross-disciplinary themes: Make and Preserve the Future; Connect the People and Cities; and Protect and Care

    How future surgery will benefit from SARS-COV-2-related measures: a SPIGC survey conveying the perspective of Italian surgeons

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    COVID-19 negatively affected surgical activity, but the potential benefits resulting from adopted measures remain unclear. The aim of this study was to evaluate the change in surgical activity and potential benefit from COVID-19 measures in perspective of Italian surgeons on behalf of SPIGC. A nationwide online survey on surgical practice before, during, and after COVID-19 pandemic was conducted in March-April 2022 (NCT:05323851). Effects of COVID-19 hospital-related measures on surgical patients' management and personal professional development across surgical specialties were explored. Data on demographics, pre-operative/peri-operative/post-operative management, and professional development were collected. Outcomes were matched with the corresponding volume. Four hundred and seventy-three respondents were included in final analysis across 14 surgical specialties. Since SARS-CoV-2 pandemic, application of telematic consultations (4.1% vs. 21.6%; p < 0.0001) and diagnostic evaluations (16.4% vs. 42.2%; p < 0.0001) increased. Elective surgical activities significantly reduced and surgeons opted more frequently for conservative management with a possible indication for elective (26.3% vs. 35.7%; p < 0.0001) or urgent (20.4% vs. 38.5%; p < 0.0001) surgery. All new COVID-related measures are perceived to be maintained in the future. Surgeons' personal education online increased from 12.6% (pre-COVID) to 86.6% (post-COVID; p < 0.0001). Online educational activities are considered a beneficial effect from COVID pandemic (56.4%). COVID-19 had a great impact on surgical specialties, with significant reduction of operation volume. However, some forced changes turned out to be benefits. Isolation measures pushed the use of telemedicine and telemetric devices for outpatient practice and favored communication for educational purposes and surgeon-patient/family communication. From the Italian surgeons' perspective, COVID-related measures will continue to influence future surgical clinical practice

    FATTORI DI FORMA DA INTAGLIO LATERALE FORMULE CLASSICHE E VERIFICA FEM

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    Alcuni degli esiti traibili dalle tante formule, quelle tradizionali, di piĂą comune impiego, nel tempo proposte per la valutazione del fattore di forma relativo a lastre intagliate lateralmente e sotto carico monodirezionale, sono stati posti a confronto con le risultanze individuate tramite ricorso al FEM.Dando fede alla deduzioni attinte mediante il suddetto metodo, gli autori hanno elaborato anche una formula che meglio delle altre prese in esame, ed in campo piĂą esteso delle variabili del problema, approssima le citate deduzioni

    FATTORI DI FORMA DA INTAGLIO LATERALE FORMULE CLASSICHE E VERIFICA FEM

    No full text
    Alcuni degli esiti traibili dalle tante formule, quelle tradizionali, di piĂą comune impiego, nel tempo proposte per la valutazione del fattore di forma relativo a lastre intagliate lateralmente e sotto carico monodirezionale, sono stati posti a confronto con le risultanze individuate tramite ricorso al FEM.Dando fede alla deduzioni attinte mediante il suddetto metodo, gli autori hanno elaborato anche una formula che meglio delle altre prese in esame, ed in campo piĂą esteso delle variabili del problema, approssima le citate deduzioni

    On the geometric transferability of the delamination shear limit for CFRP laminate in bending

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    The laminate load bearing capability is often compromised when delamination occurs even though the laminae remain intact. The out-of-plane components of the stress tensor, defined at the interfaces between plies, are typically responsible for the delamination of multi-layered materials. Commonly used failure criteria for delamination make use of both shear and normal interlaminar stresses. In this work the out-of-plane stresses inside a woven laminate were numerically evaluated using a micromechanical model. Under three point bending the existence of local normal interlaminar stress related to the fabric architecture was demonstrated. The influence of the due to texture normal interlaminar stress on the fracture occurrence was discussed. The reduction of the apparent interlaminar shear strength as effect of the span-to-depth ratio increase was successfully reproduced introducing a dependence of the delamination shear limit from the stress triaxiality gradient
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