89 research outputs found
Device and method for converting direct current into alternate current
The device for converting direct current into alternate current comprises a multilevel converter associated with at least a source of direct current and a modulation unit having piloting means for piloting the converter for the conversion of the direct current into an alternate output current, in which the modulation unit comprises comparison means for comparing the output current value with a preset positive threshold value and a preset negative threshold value, the piloting means being suitable for piloting the converter with a pulse modulation of the unipolar type in the event of the output current value being above the positive threshold value or below the negative threshold value and with a pulse modulation of the complementary type in the event of the output current value being below the positive threshold value and above the negative threshold value. The method for converting direct current into alternate current comprises a piloting phase of a multilevel converter for the conversion of a direct voltage into an alternate output voltage, a comparison phase of the output current value with a preset positive threshold value and a preset negative threshold value, the piloting phase being suitable for piloting the converter with a pulse modulation of the unipolar type in the event of the output current value being above the positive threshold value or below the negative threshold value and with a pulse modulation of the complementary type in the event of the output current value being below the positive threshold value and above the negative threshold value
Istallazione di una stazione per la rivelazione continua Radon mediante spettrometria alfa nella Solfatara di Pozzuoli
INGV (Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Napoli - Osservatorio Vesuviano)Published1-221.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveN/A or not JCRrestricte
Il sistema di monitoraggio sismico dell’Osservatorio Vesuviano – INGV
Obiettivo principale del monitoraggio dei vulcani attivi è individuare e misurare fenomeni che possono essere indotti dal movimento del magma in profondità . Dal punto di vista sismologico questi fenomeni possono essere sciami sismici, eventi a bassa frequenza, microtremore vulcanico ed eventi very long period (VLP). Attraverso la misura, l'analisi e la corretta interpretazione di questi fenomeni è possibile capire in anticipo se un vulcano sta evolvendo verso una ripresa dell'attività eruttiva.
L'Osservatorio Vesuviano - INGV ha tra i suoi compiti istituzionali il monitoraggio del Vesuvio, dei Campi Flegrei e di Ischia che sono, come è noto, vulcani a alto rischio a causa del loro stile eruttivo prevalentemente esplosivo e della presenza nelle loro prossimità di vaste aree urbanizzate.
Per effettuare il monitoraggio sismologico di dette aree l'Osservatorio Vesuviano ha sviluppato e mantiene una rete che trasmette i dati in continuo al centro di sorveglianza. La configurazione attuale della rete comprende 28 stazioni analogiche a corto periodo (1Hz) e 4 stazioni digitali a larga banda.PublishedRoma1.4. TTC - Sorveglianza sismologica delle aree vulcaniche attiveope
ISTALLAZIONE DI UNA STAZIONE PER LA RIVELAZIONE CONTINUA RADON MEDIANTE SPETTROMETRIA ALFA NELLA SOLFATARA DI POZZUOLI
La realizzazione della stazione descritta nel presente rapporto è frutto di una collaborazione tra ricercatori
della Sezione di Napoli dell’ Istituto Nazionale di Fisica Nucleare (INFN) e ricercatori dell’Osservatorio
Vesuviano (OV), Sezione di Napoli dell’Istituto Nazionale di Geofisica e Vulcanologia (INGV), e costituisce
un’attività sperimentale per il monitoraggio dell’attività vulcanica dei Campi Flegrei.INGV Istituto Nazionale di Geofisica e VulcanologiaPublished1.2. TTC - Sorveglianza geochimica delle aree vulcaniche attive2.4. TTC - Laboratori di geochimica dei fluidi4.5. Studi sul degassamento naturale e sui gas petroliferiope
INVESTIGATING THE SEISMIC RESPONSE OF URM WALLS WITH IRREGULAR OPENING LAYOUT THROUGH DIFFERENT MODELING APPROACHES
The façade and internal walls of unreinforced masonry (URM) buildings often present an irregular opening layout, due to architectural reasons or modifications to the structure, which make the expected seismic damage pattern less predictable a priori. Therefore, the discretization of the walls in structural components is not standardized, conversely to cases with a regular opening layout for which the available modeling methods are corroborated by seismic damage surveys reporting recurrent failure patterns. The structural component discretization is a relevant step for the code-conforming seismic assessment, typically based on comparing the internal forces and drifts of each component to strength criteria and drift thresholds. Therefore, the lack of well-established approaches can significantly influence the assessment. The issue is even more evident when the structural components must be identified a priori in the modeling stage, namely for equivalent frame models. The applicability of available methods for discretization of URM walls with irregular opening layout has been already investigated in literature, but a conclusive judgment requires further studies. In this context, this paper presents an overview of the preliminary results addressing the numerical modeling of this type of walls within the framework of the DPC-ReLUIS 2022-2024 project (Subtask 10.3), funded by the Italian Department of Civil Protection. The Subtask aims to propose consensus-based recommendations for researchers and practitioners which can contribute to harmonize the use of different modeling approaches. Seven research groups are involved in the research, adopting different modeling approaches and computer codes, but similar assumptions and the same analysis method (pushover) are used. The benchmark URM structure illustrated in the paper is a two-story wall from which four configurations with increasing irregularity of opening layout were derived. The results of four modeling approached are presented. Three of them reproduce the mechanical response of masonry at the material scale by means of FE models implemented in OpenSees, DIANA and Abaqus software, while the remaining approach describes the mechanical response of masonry at the macro-element scale in 3DMacro software. Results were compared in terms of capacity curves, predicted failure mechanisms and evolution of internal forces in piers. The adoption of consistent assumptions among the different approaches led to an overall agreement of predictions at both wall and pier scales, particularly in terms of damage pattern with higher concentration of damage at the ground story. Despite that, differences on the pushover curves have been highlighted. They are mainly due to some deviations of the internal forces in squat piers deriving from a complex load flow in these elements
Investigating the seismic response of URM walls with irregular opening layout through different modeling approaches
TThe façade and internal walls of unreinforced masonry (URM) buildings often present an
irregular opening layout, due to architectural reasons or modifications to the structure, which
make the expected seismic damage pattern less predictable a priori. Therefore, the
discretization of the walls in structural components is not standardized, conversely to cases
with a regular opening layout for which the available modeling methods are corroborated by
seismic damage surveys reporting recurrent failure patterns. The structural component
discretization is a relevant step for the code-conforming seismic assessment, typically based
on comparing the internal forces and drifts of each component to strength criteria and drift
thresholds. Therefore, the lack of well-established approaches can significantly influence the
assessment. The issue is even more evident when the structural components must be identified
a priori in the modeling stage, namely for equivalent frame models. The applicability of
available methods for discretization of URM walls with irregular opening layout has been
already investigated in literature, but a conclusive judgment requires further studies.
In this context, this paper presents an overview of the preliminary results addressing the
numerical modeling of this type of walls within the framework of the DPC-ReLUIS 2022-2024
project (Subtask 10.3), funded by the Italian Department of Civil Protection. The Subtask
aims to propose consensus-based recommendations for researchers and practitioners which
can contribute to harmonize the use of different modeling approaches. Seven research groups
are involved in the research, adopting different modeling approaches and computer codes,
but similar assumptions and the same analysis method (pushover) are used. The benchmark
URM structure illustrated in the paper is a two-story wall from which four configurations
with increasing irregularity of opening layout were derived. The results of four modeling
approached are presented. Three of them reproduce the mechanical response of masonry at
the material scale by means of FE models implemented in OpenSees, DIANA and Abaqus
software, while the remaining approach describes the mechanical response of masonry at the
macro-element scale in 3DMacro software. Results were compared in terms of capacity
curves, predicted failure mechanisms and evolution of internal forces in piers. The adoption
of consistent assumptions among the different approaches led to an overall agreement of
predictions at both wall and pier scales, particularly in terms of damage pattern with higher
concentration of damage at the ground story. Despite that, differences on the pushover curves
have been highlighted. They are mainly due to some deviations of the internal forces in squat
piers deriving from a complex load flow in these elements.DPC - Dipartimento della Protezione Civile, Presidenza del Consiglio dei Ministri(LA/P/0112/2020
Litostratigrafia di alta risoluzione nel Cretacico Inferiore di Monte Raggeto (Monte Maggiore, Appennino Campano).
Atti II Convegno FIST, Bellaria, 1, 74-76
Orbital Regulation Of Stratal Frameworks, Cretaceous Carbonate Platforms Of Southern Italy.
Wildhaus, Svizzer
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