Search results for " Fault"

showing 10 items of 239 documents

DC/DC converter topologies for electrolyzers: State-of-the-art and remaining key issues.

2017

In recent years, the use of electrolyzers to produce cleanly and efficiently hydrogen from renewable energy sources (i.e. wind turbines, photovoltaic) has taken advantage of a growing interest from researchers and industrial. Similarly to fuel cells, DC/DC converters are needed to interface the DC bus with the electrolyzer. Usually, electrolyzers require a low DC voltage to produce hydrogen from water. For this reason, a DC/DC buck converter is generally used for this purpose. However, other DC/DC converter topologies can be used depending on the feature of the electrolyzer and electrical grid as well. The main purpose of this paper is to present the current state-of-the-art of DC/DC conver…

Forward converterRenewable Energy Sustainability and the Environmentbusiness.industryBuck converterFlyback converterComputer science020209 energy020208 electrical & electronic engineeringĆuk converterElectrical engineeringEnergy Engineering and Power TechnologyElectrolyzer DC/DC converter Renewable energy sources Current ripple Energy efficiency Power switch fault-tolerance02 engineering and technologyConvertersCondensed Matter PhysicsDC-BUSPower optimizerFuel TechnologySettore ING-INF/04 - Automatica0202 electrical engineering electronic engineering information engineeringCharge pumpbusiness
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Sedimentological and tectonic context of Paleoproterozoïque Franceville basin (Gabon) : fluid pressure structures, bitumen and uranium mineralization

2016

Metallogenic deposits within paleproterozoic basins depend on generation and migration of fluids. The aim of this study is to provide a better understanding of tectonic, sedimentological and diagenetic setting of the uranium deposits in the Franceville basin and to characterize hydraulic fracturing impact on fluid migration processes in sandstone reservoirs.Tectonic study define the N180-170° transfer faults, associated with Archean tectonic and the N110-120° longitudinal normal faults. These two fault directions split the Franceville basin into small sub-basins. The longitudinal normal faults are associated with footwall anticlines and hanging wall synclines. The uranium deposits of France…

Fracturation hydrauliqueBassin de FrancevilleFailles de transfertUranium mineralizationTransfer faultsHydraulic fracturingPaleoproterozoicBarrières de perméabilitéFootwall anticlinesStructures de surpression fluidesLongitudinal normal faultsFranceville basinAnticlinal de murBitumen[SDU.STU] Sciences of the Universe [physics]/Earth SciencesUraniumFluid pressure structuresPaléoprotérozoïqueBitumePermeability barriersFailles longitudinales
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Characterization of clamp-on current transformers under nonsinusoidal conditions

2009

This paper reports the performance of clamp-on current transformers under nonsinusoidal conditions. A set of experimental measurements helped to determine the ratio and the phase errors under two conditions: 1) sinusoidal excitation with frequencies from 45 to 1000 Hz and 2) nonsinusoidal excitation using the fundamental frequency and one harmonic, with adjusted phase shift. It was found that ratio and phase errors are affected by the phase angle between the harmonic and the fundamental and the harmonic amplitude. The effects of conductor location in the current transformer's window and of the air-gap width were also investigated. It was concluded that harmonic phase and ratio errors measur…

Frequency responseMaterials scienceElectric current measurementTransductorAcousticsErrorsTransducersPhase (waves)Energy Engineering and Power TechnologyClamp-on current transformers current transformers (CTs) frequency response power system harmonics transducers.Power transformersDistributed power generationElectric power systemsHarmonic analysisElectric power transmission networksClamp-on current transformersCurrent transformersFrequency responsePower electronicsFrequency measurementElectronic engineeringElectrical and Electronic EngineeringElectrical conductorTomographyComputed tomographyElectric power distributionElectric transformersCircuit faultsFault currentsFundamental frequencyComputerized tomographyFourier seriesCurrent measurementCurrent transformerDiagnostic radiographyElectric instrument transformersElectric frequency measurementPower system harmonicsMedical imagingCurrent transformers (CTs)Air gap (plumbing)Power transmissionElectric network analysisExcitation
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Fuzzy fault tree analysis in modern γ-ray industrial irradiator: Use of fuzzy version of HEART and CREAM techniques for human error evaluation

2008

As well known, the lack of accurate quantitative human reliability data is a serious limitation and source of uncertainty in risk assessment. Therefore, in the last years, many Authors suggested that the use of the fuzzy sets theory can fill up this gap, performing as useful tool when dealing with qualitative or vague information. In such a framework, the present paper refers to the obtained results by using Fuzzy Fault Tree analyses of accidental scenarios which entail the potential exposure of operators working in γ-ray irradiation industrial plant. For these analyses the HEART methodology, a first generation HRA (Human Reliability Analysis) method, has been employed to evaluate the proba…

Fuzzy fault tree analysiIrradiation industrial plantHEARTCREAMSettore ING-IND/19 - Impianti Nucleari
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Fault role in geological processes. Repeated changing of activity mode and magnitude from basin formation to mountain belt staking: the case of the S…

2010

GEOLOGICAL PROCESSES FAULT ROLE SICILIAN CHAIN
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Coseismic Damage at an Archaeological Site in Sicily, Italy: Evidence of Roman Age Earthquake Surface Faulting

2018

Archaeoseismology can provide a useful chronological tool for constraining earthquakes and documenting significant evidence that would otherwise be lost. In this paper, we report a case of surface faulting on ancient man-made structures belonging to the archaeological site of Santa Venera al Pozzo situated along the eastern flank of Mt. Etna volcano in eastern Sicily (southern Italy), which is affected by well-developed tectonic faults. Geological surveys highlight a set of fractures affecting the archaeological ruins, suggesting the occurrence of a capable fault zone across the area. An integrated geophysical survey was carried out in order to identify the main subsurface tectonic disconti…

Geophysical investigation Archaeoseismological analysis Surface faulting Santa Venera al Pozzo Etna volcano010504 meteorology & atmospheric sciences010502 geochemistry & geophysics01 natural sciencesArchaeologyTectonicsGeophysicsDiscontinuity (geotechnical engineering)Etna volcanoGeochemistry and PetrologySettore GEO/11 - Geofisica ApplicataSeismic refractionElectrical resistivity tomographyRoman ageGeology0105 earth and related environmental sciencesArchaeoseismology
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The Antarctic yeast Candida sake: Understanding cold metabolism impact on wine

2017

Current winemaking trends include low-temperature fermentations and using non-Saccharomyces yeasts as the most promising tools to produce lower alcohol and increased aromatic complexity wines. Here we explored the oenological attributes of a C. sake strain, H14Cs, isolated in the sub-Antarctic region. As expected, the cold sea water yeast strain showed greater cold growth, Na+-toxicity resistance and freeze tolerance than the S. cerevisiae QA23 strain, which we used as a commercial wine yeast control. C. sake H14Cs was found to be more sensitive to ethanol. The fermentation trials of low-sugar content must demonstrated that C. sake H14Cs allowed the cold-induced lag phase of growth to be el…

Glycerol0301 basic medicine030106 microbiologyAroma of wineWineSugars in wineFructoseSaccharomyces cerevisiaeBiologyMicrobiology03 medical and health sciencesYeast DriedMalolactic fermentationBiomassFood scienceCandidaWinemakingWineFermentation in winemakingEthanolSodiumfood and beveragesGeneral MedicineWine faultCulture MediaCold TemperatureYeast in winemakingGlucoseFermentationFood ScienceInternational Journal of Food Microbiology
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Middle Miocene graben development in Crete and its possible relation to large-scale detachment faults in the southern Aegean

2001

The linkage between the development of south-facing Cretan graben and large-scale detachment faulting in the southern Aegean is unknown. Widespread Serravallian deposits in the Ierapetra graben of Crete supply constraints to Middle Miocene graben development in the southern Aegean. The Ierapetra graben, and by inference the Cretan graben in general, were hitherto believed to have formed as a result of sinistral transpression during N–S shortening. We argue that the formation of the Cretan graben is due to N–S extension. The south-dipping, N–S-extending Kritsa normal fault served as the master fault controlling graben development in the Ierapetra graben. The Kritsa normal fault is either an …

GrabenDetachment faultHorst and grabengeographySinistral and dextralgeography.geographical_feature_categoryGeologyFault (geology)Normal faultTranspressionGeologySeismologyTerra Nova
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An Improved Approach to the Simulation of Single-Line-to-Ground Faults in Transmission Networks

2009

These paper presents a mathematical model for studying the Single-Line-to-Ground fault in transmission networks, giving a personal contribution for a methodical and accurate analysis of complex systems, by providing an evolution of the “circuital method” able to solve the case of a system in which more than one line supply the fault.

Ground Fault Safety Circuital MethodSettore ING-IND/33 - Sistemi Elettrici Per L'Energia
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Studio della sicurezza di una stazione di rifornimento di idrogeno per autotrazione mediante l’uso integrato di tecniche di analisi di rischio

2008

HAZOP FMEA FAULT TREE
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