765 research outputs found

    Assessing the risk of vehicle instability due to flooding

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    [EN] Flooding can destabilize vehicles which might, in turn, exacerbate the negative effects of floods when vehicles are swept away by flows, and lead to economic loss and fatalities. In order to suitably manage floods, it is necessary to determine the risk of instability to which vehicles in flood-prone areas are subject. This paper develops a methodology to estimate this risk based on the characteristics of floods and the vehicle fleet located in potential flood-prone areas. This risk is determined by the statistical integral of the instability hazard and vehicles' vulnerability. The instability hazard was established by a stability function of partially submerged cars and flood frequency, while vulnerability was calculated by combining the susceptibility and exposure of cars. Our methodology was applied in the towns of Alfafar and Massanassa (Spain). It found that the annualized instability risk due to flooding could be relatively high on most streets and roads, with values reaching the order of 8.4 at-risk vehicles per hectare/year.Departamento Administrativo de Ciencia, Tecnologia e Innovacion COLCIENCIAS (Colombia) call, Grant/Award Number: 728-2015; Spanish Ministry of Science and Innovation through the research project TETISCHANGE, Grant/Award Number: RTI2018-093717-B-I00Bocanegra, RA.; Francés, F. (2021). Assessing the risk of vehicle instability due to flooding. Journal of Flood Risk Management. 14(4):1-15. https://doi.org/10.1111/jfr3.12738S11514

    Diavideos: a Diabetes Health Video Portal

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    Diavideos1 is a web platform that collects trustworthy diabetes health videos from YouTube and offers them in a easy way. YouTube is a big repository of health videos, but good content is sometimes mixed with misleading and harmful videos such as promoting anorexia [1].Diavideos is a web portal that provides easy access to a repository of trustworthy diabetes videos. This poster describes Diavideos and explains the crawling method used to retrieve these videos from trusted channels

    Spacecraft VLBI and Doppler tracking: algorithms and implementation

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    We present the results of several multi-station Very Long Baseline Interferometry (VLBI) experiments conducted with the ESA spacecraft Venus Express as a target. To determine the true capabilities of VLBI tracking for future planetary missions in the solar system, it is necessary to demonstrate the accuracy of the method for existing operational spacecraft. We describe the software pipeline for the processing of phase referencing near-field VLBI observations and present results of the ESA Venus Express spacecraft observing campaign conducted in 2010-2011. We show that a highly accurate determination of spacecraft state-vectors is achievable with our method. The consistency of the positions indicates that an internal rms accuracy of 0.1 mas has been achieved. However, systematic effects produce offsets up to 1 mas, but can be reduced by better modelling of the troposphere and ionosphere and closer target-calibrator configurations.Comment: 10 pages, 10 figures. Astronomy and Astrophysics, accepte

    Métodos para evaluar interacciones entre cuerpos de agua en un humedal y aplicación en dos casos de estudio

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    La comprensión de la dinámica de ecosistemas dependientes del recurso hídrico subterráneo, como pueden llegar a serlo algunos humedales, parte del conocimiento del sistema hidrológico. Para alcanzar esta meta se aplica una serie de métodos y procedimientos de análisis que comprenden la caracterización hi-drogeológica, la delimitación del área de captura de agua hacia el humedal, el monitoreo piezométrico, la rea-lización de balances de masas. La modelación numérica, los análisis hidrogeoquímicos y los métodos isotópi-cos permiten refinar y validar los modelos conceptuales. En el marco del proyecto Hydrochemical and isotopic techniques for assessment hidrological proccesses on wetlands, promovido entre los años 2006 y 2011 por la Agencia Internacional de Energía Atómica (IAEA), Colombia y Argentina compartieron conoci-miento y experiencias para entender la dinámica de los humedales Ciénaga Colombia y La Salada. En este texto se resumen aspectos metodológicos y los resultados de los dos casos de estudio considerados.The Understanding of ecosystem dynamics, for example the wetlands, depends of the knowledge of the hydrologic system. Many techniques can be used in order to obtain a good conceptual mod-el of the wetlands and its catchment area: hydrogeology, numerical modeling, hydrogeochemestry, and iso-tope hydrology. researchers of Argentina and Colombia studied -According with the project: ―Hydrochemical and isotopic techniques for assessment hidrological proccesses on wetlands‖ (IAEA, 2006 to 2011)- two wet-lands hydrogeology dependent: La salada Pond and Cienaga Colombia Weltand. These projects used method-ologies similar and they obtained validated hydrological models

    Review and analysis of vehicle stability models during floods and proposal for future improvements

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    This is the peer reviewed version of the following article: Bocanegra, RA, Vallés-Morán, FJ, Francés, F. Review and analysis of vehicle stability models during floods and proposal for future improvements. J Flood Risk Management. 2020; 13 ( Suppl. 1):e12551, which has been published in final form at https://doi.org/10.1111/jfr3.12551. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.[EN] Flood water can affect vehicles significantly, which in turn can increase the negative effects of floods as vehicles are washed away by the flow and become a form of debris. In cities, most fatalities during floods occur inside vehicles. Consequently, it is necessary to establish thresholds for vehicle stability during this type of event to provide information necessary for flood risk management. This article analyses the available stability models developed over recent years to determine such thresholds. The stability models were grouped according to the way in which they approached car watertightness and the stability thresholds proposed by each of them were compared. It was found that these thresholds vary over a relatively wide range. Additionally, the experimental data were compared with the results provided by these studies leading to the conclusion that several of the stability models analysed do not fit measured data well. New research is required to overcome the simplifications made by the state-of-the-art models and to try to standardise the decision criteria which should be adopted to define stability thresholds for vehicles of different characteristics.Departamento Administrativo de Ciencia, Tecnologia e Innovacion COLCIENCIAS (Colombia) call 728-2015; Spanish Ministry of Science and Innovation through the research project TETISCHANGE, Grant/Award Number: RTI2018-093717-B-I00.Bocanegra, RA.; Vallés-Morán, FJ.; Francés, F. (2020). Review and analysis of vehicle stability models during floods and proposal for future improvements. Journal of Flood Risk Management. 13:1-13. https://doi.org/10.1111/jfr3.12551S11313Arrighi, C., Alcèrreca-Huerta, J. C., Oumeraci, H., & Castelli, F. (2015). Drag and lift contribution to the incipient motion of partly submerged flooded vehicles. Journal of Fluids and Structures, 57, 170-184. doi:10.1016/j.jfluidstructs.2015.06.010Arrighi C. Castelli F. &Oumeraci H.(2016). Effects of flow orientation on the onset of motion of flooded vehicles. InProceedings of the 4th IAHR Europe Congress. Liege DOI:https://doi.org/10.1201/b21902-140.Arrighi, C., Huybrechts, N., Ouahsine, A., Chassé, P., Oumeraci, H., & Castelli, F. (2016). Vehicles instability criteria for flood risk assessment of a street network. Proceedings of the International Association of Hydrological Sciences, 373, 143-146. doi:10.5194/piahs-373-143-2016Bonham A. J. &Hattersley R. T.(1967).Low level causeways. WRL Report No. 100. University of New South Wales. Sydney Australia.Cox R. J. Shand T. D. &Blacka M. J.(2010). Appropriate safety criteria for people in floods.Australian Rainfall and Runoff. WRL Research Report 240. Report for Institution of Engineers Australia.DROBOT, S., BENIGHT, C., & GRUNTFEST, E. (2007). Risk factors for driving into flooded roads. Environmental Hazards, 7(3), 227-234. doi:10.1016/j.envhaz.2007.07.003FitzGerald, G., Du, W., Jamal, A., Clark, M., & Hou, X.-Y. (2010). Flood fatalities in contemporary Australia (1997-2008). Emergency Medicine Australasia, 22(2), 180-186. doi:10.1111/j.1742-6723.2010.01284.xGordon A. D. &Stone P. B.(1973).Car stability on road causeways. WRL Technical Report No. 73/12. University of New South Wales. Sydney Australia.Jonkman, S. N., & Kelman, I. (2005). An Analysis of the Causes and Circumstances of Flood Disaster Deaths. Disasters, 29(1), 75-97. doi:10.1111/j.0361-3666.2005.00275.xKellar, D. M. M., & Schmidlin, T. W. (2012). Vehicle-related flood deaths in the United States, 1995-2005. Journal of Flood Risk Management, 5(2), 153-163. doi:10.1111/j.1753-318x.2012.01136.xKeller R. J. &Mitsch B.(1993).Safety aspects of the design of roadways as floodways. Research Report No. 69 Urban Water Research Association of Australia.Kramer, M., Terheiden, K., & Wieprecht, S. (2016). Safety criteria for the trafficability of inundated roads in urban floodings. International Journal of Disaster Risk Reduction, 17, 77-84. doi:10.1016/j.ijdrr.2016.04.003Martínez-Gomariz, E., Gómez, M., Russo, B., & Djordjević, S. (2016). Stability criteria for flooded vehicles: a state-of-the-art review. Journal of Flood Risk Management, 11, S817-S826. doi:10.1111/jfr3.12262Martínez-Gomariz, E., Gómez, M., Russo, B., & Djordjević, S. (2017). A new experiments-based methodology to define the stability threshold for any vehicle exposed to flooding. Urban Water Journal, 14(9), 930-939. doi:10.1080/1573062x.2017.1301501Mens M. J. Erlich M. Gaume E. Lumbroso D. Moreda Y. Van der VatM. &Versini P. A.(2008).Frameworks for flood event management. Report Number T19‐07‐03. WL Delft Hydraulics. Delft Netherlands.Moore, K. A., & Power, R. K. (2002). Safe Buffer Distances for Offstream Earth Dams. Australasian Journal of Water Resources, 6(1), 1-15. doi:10.1080/13241583.2002.11465206Oshikawa H. &Komatsu T.(2014). Study on the risk evaluation for a vehicular traffic in a flood situation.Proceedings of the 19th IAHR‐APD Congress Hanoi Vietnam.Pregnolato, M., Ford, A., Wilkinson, S. M., & Dawson, R. J. (2017). The impact of flooding on road transport: A depth-disruption function. Transportation Research Part D: Transport and Environment, 55, 67-81. doi:10.1016/j.trd.2017.06.020Shand T. Cox R. Blacka M. &Smith G.(2011).Australian Rainfall and Runoff (AR&R). Appropriate safety criteria for vehicles. Australian rainfall and runoff revision project 10: Report Number: P10/S2/020. Sidney Australia.Shu, C., Xia, J., Falconer, R. A., & Lin, B. (2011). Incipient velocity for partially submerged vehicles in floodwaters. Journal of Hydraulic Research, 49(6), 709-717. doi:10.1080/00221686.2011.616318Smith G. P. Davey E. K. &Cox R. J.(2014).Flood hazard. WRL Technical Report 2014/07. University of New South Wales. Sydney Australia.Smith G. P. Modra B. D. Tucker T. A. &Cox R. J.(2017).Vehicle stability testing for flood flows. WRL Technical Report 2017/07. University of New South Wales. Sydney Australia.Suarez, P., Anderson, W., Mahal, V., & Lakshmanan, T. R. (2005). Impacts of flooding and climate change on urban transportation: A systemwide performance assessment of the Boston Metro Area. Transportation Research Part D: Transport and Environment, 10(3), 231-244. doi:10.1016/j.trd.2005.04.007Teo, F. Y., Xia, J., Falconer, R. A., & Lin, B. (2012). Experimental studies on the interaction between vehicles and floodplain flows. International Journal of River Basin Management, 10(2), 149-160. doi:10.1080/15715124.2012.674040Versini, P.-A., Gaume, E., & Andrieu, H. (2010). Application of a distributed hydrological model to the design of a road inundation warning system for flash flood prone areas. Natural Hazards and Earth System Sciences, 10(4), 805-817. doi:10.5194/nhess-10-805-2010Versini, P.-A., Gaume, E., & Andrieu, H. (2010). Assessment of the susceptibility of roads to flooding based on geographical information – test in a flash flood prone area (the Gard region, France). Natural Hazards and Earth System Sciences, 10(4), 793-803. doi:10.5194/nhess-10-793-2010Xia, J., Falconer, R. A., Xiao, X., & Wang, Y. (2013). Criterion of vehicle stability in floodwaters based on theoretical and experimental studies. Natural Hazards, 70(2), 1619-1630. doi:10.1007/s11069-013-0889-2Xia, J., Teo, F. Y., Lin, B., & Falconer, R. A. (2010). Formula of incipient velocity for flooded vehicles. Natural Hazards, 58(1), 1-14. doi:10.1007/s11069-010-9639-

    Determinación de relaciones nivel – caudal simple o compleja en un río. Caso del río Cauca

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    (Eng) The stage – discharge relationship in a river, or rating curve, is very useful because it allows calculating the discharg - es from measured stages or water levels in a gauge station. For a nearly steady regime a discharge corresponds to a water level (simple relationship). However, frequently different circumstances can originate a complex relation between waters levels and discharges and then a discharge can be referred to two water levels and vice versa. In this study, simple and complex rating curves were determined in La Balsa hydrometric station, located 27 km downstream of Salvajina reservoir (Cauca river, Colombia). The simple curve was calculated by applying the log - arithmic method, which allows identifying the characteristics of the type of control that determines the water level – discharge relationship. The complex curve was calculated by using the method of storage per unit rate of variation in water levels, which allows adjusting the discharge obtained with the rating curve for steady flow considering a storage due to the variation in the level. The results show significant differences in the estimated discharges through the two relationships. By applying the two rating curves for a moderate flood (01/01/1999) differences up to 19% were estimated between both calculated discharges. In consequence, in order to get the appropriated rating curve it should to carry out a rigorous analysis of the flow conditions on the river reaches of the hydrometric station.(Spa) La relación nivel de agua – caudal en un río, denominada también curva de calibración, es de gran utilidad práctica pues permite estimar los caudales a partir de los niveles registrados en una estación hidrométrica. Cuando el régimen es aproximadamente permanente a cada nivel le corresponde un caudal (relación simple). No obstante, frecuente - mente diferentes circunstancias pueden generar una relación compleja entre los niveles y los caudales, donde un caudal puede estar relacionado con dos niveles de agua y viceversa. En el presente estudio se determinaron las cur - vas de calibración simple y compleja en la estación La Balsa, localizada 27 km aguas abajo del embalse de Salvajina (río Cauca, Colombia). La curva simple se calculó mediante el método logarítmico, el cual permite identificar las características del tipo de control que determina la relación nivel – caudal. La curva compleja se calculó según el método de almacenamiento por unidad de tasa de cambio en los niveles de agua, el cual permite ajustar el caudal obtenido en la curva nivel – caudal para régimen permanente considerando un almacenamiento debido al cambio en el nivel. Los resultados muestran diferencias importantes en los caudales estimados por medio de las dos relaciones. Al aplicar las dos curvas de calibración para una creciente moderada (01/01/1999) se encontraron diferencias hasta de un 19% entre los caudales calculados. En consecuencia, para establecer la curva de calibración nivel-caudal apropiada se debe realizar un análisis riguroso de las condiciones del flujo, tanto en la estación hidrométrica como aguas arriba y aguas abajo de ella

    Planetary Radio Interferometry and Doppler Experiment (PRIDE) Technique: a Test Case of the Mars Express Phobos Fly-by. 2. Doppler tracking: Formulation of observed and computed values, and noise budget

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    Context. Closed-loop Doppler data obtained by deep space tracking networks (e.g., NASA's DSN and ESA's Estrack) are routinely used for navigation and science applications. By "shadow tracking" the spacecraft signal, Earth-based radio telescopes involved in Planetary Radio Interferometry and Doppler Experiment (PRIDE) can provide open-loop Doppler tracking data when the dedicated deep space tracking facilities are operating in closed-loop mode only. Aims. We explain in detail the data processing pipeline, discuss the capabilities of the technique and its potential applications in planetary science. Methods. We provide the formulation of the observed and computed values of the Doppler data in PRIDE tracking of spacecraft, and demonstrate the quality of the results using as a test case an experiment with ESA's Mars Express spacecraft. Results. We find that the Doppler residuals and the corresponding noise budget of the open-loop Doppler detections obtained with the PRIDE stations are comparable to the closed-loop Doppler detections obtained with the dedicated deep space tracking facilities

    Herramientas hidrogeoquímicas aplicadas a la evaluación del acuífero de Trenque Lauquen, provincia de Buenos Aires, Argentina

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    La ciudad de Trenque Lauquen en la provincia de Buenos Aires, Argentina se abastece exclusivamente del recurso hídrico subterráneo. El objetivo del trabajo es analizar la evolución temporal en la calidad fisicoquímica del agua, teniendo en cuenta las características hidrogeológicas y los procesos con la matriz sólida. La metodología consistió en la valoración y síntesis de la información geológica, geofísica, hidrogeológica e hidroquímica y la modelación de procesos hidrogeoquímicos. El agua del acuífero incrementa su salinidad con la profundidad de explotación y evoluciona hacia una disolución de yeso y precipitación de calcita, con el consiguiente incremento del contenido de sulfatos y de dureza. Se consideran apropiadas las medidas de gestión en los últimos años, que condujeron a realizar perforaciones más someras y con menor caudal de extracción, lo que ha permitido que la tendencia creciente a la salinización haya disminuido su tasa de evolución, mejorando la calidad del agua subterránea.The city of Trenque Lauquen in the Buenos Aires Province, Argentina, gets water supply ex-clusively from groundwater resources. The goal of this study is to analyze time trends related to water quality, taking into account hydrogeological characteristics and processes with the solid matrix. The methodology consisted in the assessment and summary of geological, geophysical, hydrogeological and hydrochemical in-formation, and hydrogeochemical modelling. Groundwater salinity increases with the depth of exploitation and evolves into a gypsum dissolution and calcite precipitation, increasing sulphate content and hardness. Water management measures in recent years, based on shallow wells and lower extraction volumes became appropriate since the rate of salinization has decreased improving groundwater quality

    A Nori but not a Konbu, dietary supplement decreases the cholesterolaemia, liver fat infiltration and mineral bioavailability in hypercholesterolaemic growing Wistar rats

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    The nutritional consequences of algae consumption in young populations consuming hypercholesterolaemic diets have hardly been investigated. This study tests the effect of algae supplementation of cholesterol-enriched balanced diets on growth, dietary efficiency ratio, mineral intake and absorption, organ weight and structure and cholesterolaemia in growing Wistar rats. Three groups of ten rats each were fed for 3 weeks with experimental diets containing 93% casein-soyabean oil base with 2.4% cholesterol-raising agent and 7% supplement. The control group received cellulose (35%), group 2 consumed Nori (33.8% fibre) and group 3 consumed Konbu (36.1% fibre). Food intake and body weight gain were not significantly affected. Algae groups presented significantly higher dietary efficiency ratio values than control rats. Apparent absorption of several minerals appeared significantly affected, mainly in Nori-fed rats, with a significant decrease in the ratio of Zn and Cu intakes and apparent absorption. Nori diet significantly decreased plasma cholesterol. Algae supplement did not significantly affect organ size and structure. Control and Konbu rats showed severe liver fat infiltration, while Nori rats exhibited a significantly lower degree of lipid-like hepatocyte vacuolization but light to moderate leukocyte infiltration. Light to moderate scaling off of the epithelium and moderate submucosa oedema was observed in all groups. Although long-term studies are needed to check the possible extrapolation of these data to human subjects, it can be concluded that a Nori, but not a Konbu, dietary supplement reverses the negative effect of dietary cholesterol intake and also appears to be related to mineral availability in growing subjects. © 2007 The Authors.This work was granted by the Spanish Ministerio de Investigación y Ciencia, Project AGL 2005-07204-C02-C1/ALI.Peer Reviewe
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