1,637 research outputs found
Documents on the royal appointment of Vizente Folch to subteniente de granaderos in the Regimiento Fixo de Infanteria Louisiana
No full textDocuments on the royal appointment of Vizente Folch to subteniente de granaderos in the Regimiento Fixo de Infanteria in Louisiana; includes cover sheet
CAJA 26 - LEGAJO II - SIGNATURA 9
No full textMemoriales de Carlos Folch, maestro herrero, presentando una hoja de sable y otra de cuchillo fabricandos por él mismo, pdiendo la protección de la Sociedad para establecer una fábrica en Valencia y pidiendo algún premio.Folch, C. (1796). Memoriales de Carlos Folch, maestro herrero, presentando una hoja de sable y otra de cuchillo fabricandos por él mismo, pdiendo la protección de la Sociedad para establecer una fábrica en Valencia y pidiendo algún premio. Real Sociedad Económica de Amigos del País de Valencia. https://riunet.upv.es/handle/10251/19327Importación Masiv
GIS-based tool to support civil aviation management during explosive volcanic eruptions
No full textWe present a software tool (yet under development) for short and long-term civil aviation management
in case of explosive volcanic eruptions. The tool covers the needs of stakeholders involved
in civil aviation management and interested in taking decisions based on a range of possible tephra
dispersal scenarios and/or ash dispersal forecasts. The GIS-based tool allows to display hazard and
vulnerability information, overlap maps to and estimate expected impacts (airports disrupted, routes
cancelled, etc.). We present the structure of the tool underlining the scientific background and
technical aspects of each element.
Hazard and vulnerability data are stored in a spatial database specifically designed to store deterministic
and probabilistic data sources. The database has a central role for the risk management process,
acting as a repository of maps to be used by the stakeholders for different purposes. To our knowledge,
this is the first “ad hoc” database proposed to store information about tephra dispersal hazard
and vulnerability.
The tool allows to overlap hazard and vulnerability data and estimate expected impacts through
spatially-based rules. Vulnerability and impact assessments are implemented by means of plug-ins
embedded in the GIS friendly interface. The analysis has been automated for the European air traffic
management during explosive eruptions. Results are relevant for the long-term risk assessment in
the European area. Regarding short-term, we present an example of application during an explosive
eruption at an active Icelandic volcano.
This GIS-based tool improves civil aviation management by automating short and long-term analyses
and making them faster and repeatable. Although this is only a prototype and still needs further
development, the up-to-date work can be a relevant contribution to the scientific community
Building proper invariants for subgrid-scale eddy-viscosity models
No full textSince direct simulations of the incompressible Navier-Stokes equations are limited to relatively low-Reynolds numbers, dynamically less complex mathematical formulations are necessary for coarse-grain simulations. Eddy-viscosity models for Large-Eddy Simulation is probably the most popular example thereof: they rely on differential operators that should be able to capture well different flow configurations (laminar and 2D flows, near-wall behavior, transitional regime...). Most of them are based on the combination of invariants of a symmetric second-order tensor that is derived from the gradient of the resolved velocity field. In the present work, they are presented in a framework where all the models are represented as a combination of elements of a 5D phase space of invariants. In this way, new models can be constructed by imposing appropriate restrictions in this space. The performance of the proposed models is successfully tested for a turbulent channel flow
A GIS-based tool for the estimation of impacts of volcanic ash dispersal on European air traffic
No full textImpacts of volcanic ash on air traffic have been reconsidered in the aftermath of the 2010 eruption of Eyjafjallajokull volcano (Iceland), which caused great impacts to the European air traffic network. We present a GIS-based methodology to estimate the impacts of tephra dispersal from explosive volcanic eruptions aimed at improving air traffic management
in case of ash-contaminated airspace. We use the 2010 Eyjafjallajokull eruption as a case study with two main objectives: to introduce the methodology and to perform a posteriori analysis of the 2010 aviation breakdown. Modelling results of atmospheric tephra dispersal over Europe build upon a reanalysis dataset of meteorological and volcanological parameters. Given that there is still no consensus on thresholds of ash concentration that is critical for flight safety, the methodology takes into account several ash concentration values. Results are hourly tables and
maps containing information on potentially affected airports and routes at different Flight Levels (FLs). This allows estimating impacts at a high temporal frequency. We also compute dailyaccumulated impacts for each FL. We compare our results with the 2010 impacts. Furthermore, advantages and disadvantages of this methodology are discussed and compared with similar existing tools. Finally, we underline possible improvements of the methodology and describe further work
Hazard assessment of far-range volcanic ash dispersal from a violent Strombolian eruption at Somma-Vesuvius volcano, Naples, Italy: Implications on civil aviation
No full textLong-range dispersal of volcanic ash can disrupt civil aviation over large areas, as occurred during the 2010 eruption of Eyjafjallajökull volcano in Iceland. Here we assess the hazard for civil aviation posed by volcanic ash from a potential violent Strombolian eruption of Somma-Vesuvius, the most likely scenario if eruptive activity resumed at this volcano. A Somma-Vesuvius eruption is of concern for two main reasons: (1) there is a high probability (38 %) that the eruption will be violent Strombolian, as this activity has been common in the most recent period of activity (between AD 1631 and 1944); and (2) violent Strombolian eruptions typically last longer than higher-magnitude events (from 3 to 7 days for the climactic phases) and, consequently, are likely to cause prolonged air traffic disruption (even at large distances if a substantial amount of fine ash is produced such as is typical during Vesuvius eruptions). We compute probabilistic hazard maps for airborne ash concentration at relevant flight levels using the FALL3D ash dispersal model and a statistically representative set of meteorological conditions. Probabilistic hazard maps are computed for two different ash concentration thresholds, 2 and 0. 2 mg/m 3, which correspond, respectively, to the no-fly and enhanced procedure conditions defined in Europe during the Eyjafjallajökull eruption. The seasonal influence of ash dispersal is also analysed by computing seasonal maps. We define the persistence of ash in the atmosphere as the time that a concentration threshold is exceeded divided by the total duration of the eruption (here the eruption phase producing a sustained eruption column). The maps of averaged persistence give additional information on the expected duration of the conditions leading to flight disruption at a given location. We assess the impact that a violent Strombolian eruption would have on the main airports and aerial corridors of the Central Mediterranean area, and this assessment can help those who devise procedures to minimise the impact of these long-lasting low-intensity volcanic events on civil aviation. © 2012 Springer-Verlag
Density‐driven transport in the umbrella region of volcanic clouds: Implications for tephra dispersion models
No full textLarge explosive volcanic eruptions can generate ash
clouds from rising plumes that spread in the atmosphere
around a Neutral Buoyancy Level (NBL). These ash clouds
spread as inertial intrusions and are advected by atmospheric
winds. For low mass flow rates, tephra transport is mainly
dictated by wind advection, because ash cloud spreading due
to gravity current effects is negligible (passive transport).
For large mass flow rates, gravity-driven transport at the
NBL can be the dominant transport mechanism. Conditions
under which the passive transport assumption is valid have
not yet been critically studied. We analyze the conditions
when gravity-driven transport is dominant in terms of
the cloud Richardson number. Moreover, we couple an
analytical model that describes cloud spreading as a gravity
current with an advection-diffusion model. This coupled
model is used to simulate the evolution of the volcanic
cloud during the climatic phase of the 1991 Pinatubo
eruption. Citation: Costa, A., A. Folch, and G. Macedonio (2013),
Density-driven transport in the umbrella region of volcanic clouds:
Implications for tephra dispersion models.This work has benefited from funding provided
by the Italian Presidenza del Consiglio dei Ministri - Dipartimento
della Protezione Civile (DPC), agreement INGV-DPC 2012-2013. This
paper does not necessarily represent DPC official opinion and policies.
A.F. acknowledges funding by the Spanish project ATMOST (CGL2009-10244).Published4823–48273V. Dinamiche e scenari eruttiviJCR Journalrestricte
Lipid Profile Determination by Direct Infusion ESI-MS and Fatty Acid Composition by GC-FID in Human Milk Pools by Folch and Creamatocrit Methods
No full textHuman milk (HM) is extremely important to the baby, containing a varied and balanced range of nutrients fundamental to the ideal development of the newborn. Among these nutrients, HM lipids provide 40-60% of the energy. In HM banks, the creamatocrit method is employed as a quick and solvent-free tool, however, since Folch methodology is considered reference for lipid extraction, this study compared the fatty acid (FA) composition and the lipid profile by gas chromatography with flame ionization detector (GC-FID) and direct infusion by electrospray ionization mass spectrometry (DI-ESI-MS) in pools of different HM phases, obtained from Folch and creamatocrit methods, in order to elucidate which method provides better information about HM lipids. Lipid compositon results by Folch were superior to the results obtained by creamatocrit in HM pools investigated. It means, the lipid profiles of all HM pools were more intense, and the number of FA identified by Folch was also higher in comparison to the creamatocrit method (21 and 6 FAs, respectively). GC-FID analysis in combination with principal component analysis (PCA) divided the methods, confirming a greater contribution of the Folch method. Therefore, Folch methodology revealed an effective lipid extraction in comparison to creamatocrit method.</div
Comparison of methods for determining the fatty acid composition of photosynthetic tissues
No full textThe fatty acid (FA) composition of photosynthetic tissue differs from that in other plant or animal tissues. In leaves, the lipid fraction constitutes less than 10% of the dry weight and is mostly located in the chloroplasts. An extraction solvent should dissolve polar lipids readily, but should also overcome interactions between the lipids and the tissue matrix. A mixture of chloroform/methanol (C/M) is commonly used. However, less toxic alternative methods such as hexane/isopropanol (H/I) and ethanol (E) have been suggested. In this preliminary study we compared the effectiveness of these three methods which are used as standard extraction protocols for FA analysis of plant material at three different European Universities. C/M extraction gave the highest total FA content and H/I the lowest, suggesting that C/M is indeed the best general-purpose lipid extraction solvent. Significant differences were also observed for FA composition including the ratio of saturated to unsaturated FA indicating selectivity of the various solvents in extracting different individual FA. Further and more detailed investigations are required to confirm this hypothesi
A multi-scale risk assessment for tephra fallout and airborne concentration from multiple Icelandic volcanoes – Part 2: Vulnerability and impact
No full textWe perform a multi-scale impact assessment of tephra fallout and dispersal
from explosive volcanic activity in Iceland. A companion paper (Biass et al.,
2014; "A multi-scale risk assessment of tephra fallout and airborne
concentration from multiple Icelandic volcanoes – Part I: hazard
assessment") introduces a multi-scale probabilistic assessment of tephra
hazard based on selected eruptive scenarios at four Icelandic volcanoes (Hekla,
Askja, Eyjafjallajökull and Katla) and presents probabilistic hazard maps
for tephra accumulation in Iceland and tephra dispersal across Europe. Here,
we present the associated vulnerability and impact assessment that describes
the importance of single features at national and European levels and
considers several vulnerability indicators for tephra dispersal and
deposition. At the national scale, we focus on physical, systemic and economic
vulnerability of Iceland to tephra fallout, whereas at the European scale we
focus on the systemic vulnerability of the air traffic system to tephra
dispersal. This is the first vulnerability and impact assessment analysis of
this type and, although it does not include all the aspects of physical and
systemic vulnerability, it allows for identifying areas on which further specific
analysis should be performed. Results include vulnerability maps for Iceland
and European airspace and allow for the qualitative identification of the
impacts at both scales in the case of an eruption occurring. Maps produced at
the national scale show that tephra accumulation associated with all eruptive
scenarios considered can disrupt the main electricity network, in particular in
relation to an eruption of Askja. Results also show that several power plants
would be affected if an eruption occurred at Hekla, Askja or Katla, causing a substantial systemic impact due to their
importance for the Icelandic economy. Moreover, the Askja and Katla eruptive
scenarios considered could have substantial impacts on agricultural
activities (crops and pastures). At the European scale, eruptive scenarios at
Askja and Katla are likely to affect European airspace, having
substantial impacts, in particular, in the Keflavík and London flight
information regions (FIRs), but also at FIRs above France, Germany and
Scandinavia. Impacts would be particularly intense in the case of long-lasting
activity at Katla. The occurrence of eruptive scenarios at Hekla is likely to produce high impacts at Keflavík FIR and London FIRs,
and, in the case of higher magnitude, can also impact France's FIRs. Results could
support land use and emergency planning at the national level and risk management
strategies of the European air traffic system. Although we focus on Iceland,
the proposed methodology could be applied to other active volcanic areas,
enhancing the long-term tephra risk management. Moreover, the outcomes of
this work pose the basis for quantitative analyses of expected impacts and
their integration in a multi-risk framework
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