9 research outputs found
Integrated seismic ambient noise, magnetotellurics and gravity data for the 2D interpretation of the Vallès basin structure in the geothermal system of La Garriga-Samalús (NE Spain)
The integration of geophysical methods, together with the previous information of the Vallès basin area, has resulted in the creation of a new conceptual model that explains La Garriga-Samalús geothermal system. The integration of complementary geophysical methods seems to be a good option for the preliminary stages of a geothermal system exploration, especially in urban areas. An integrated seismic ambient noise, magnetotellurics, and gravity methods were used to determine the geological units and structures which control the La Garriga-Samalús geothermal system. The 2D resistivity and density models have allowed the identification of the four main units which regulate the geothermal system: the Miocene basin, the Prelitoral Range unit, the Vallès Faut Zone, and the Paleozoic basement. The interpretation of our models set the Vallès Fault Zone, which is characterized by an anomalous low resistivity and low density, as the main path for the hot fluids. Moreover, the geophysical characterization established a new geometry for the Miocene basin. The Miocene basin presents a stepwise morphology, with the minor thickness towards the fault and an increasing thickness towards the center of the basin. This geometry seems to be related to synthetic normal faults. These results have evidenced that, although, in some geothermal systems, the warm water may create an insufficient physical contrast; the appropriate use of some techniques can still be useful for the exploration of medium and low-temperature geothermal systems
Assessment of the resilience of Barcelona urban services in case of flooding. The RESCCUE project
[ES] En el marco del Proyecto europeo RESCCUE, las proyecciones climáticas para la ciudad de Barcelona muestran aumentos significativos de las intensidades máximas de precipitación para el horizonte del 2071-2100. En este trabajo se presenta la evaluación de la resiliencia de los servicios urbanos de la ciudad frente a episodios de inundación para condiciones de lluvia actuales y futuras. El uso de modelos sectoriales e integrados ha permitido valorar la respuesta del sistema de drenaje de la ciudad tanto a nivel de sistema de alcantarillado subterráneo como a nivel superficial analizando el comportamiento hidráulico del conjunto de las superficies urbanas (calles, plazas, parques, etc.). Por otro lado, los parámetros asociados a las inundaciones superficiales (extensión de las zonas inundables, calado y velocidad) han sido empleados para estimar potenciales afectaciones futuras en otros servicios urbanos estratégicos como el tráfico superficial, el sistema eléctrico y el sistema de recogida de residuos.[EN] Within the framework of the European RESCCUE Project, climate projections for the city of Barcelona show significant increases in maximum rainfall intensities for the 2071-2100 horizon. This paper presents the evaluation of the resilience of urban services in the city against flood episodes for current and future rainfall conditions. The use of sectorial and integrated models allows to assess the response of the city’s drainage system both at the underground sewer system level and at the surface level by analyzing the hydraulic behavior of all urban surfaces (streets, squares, parks, etc.). On the other hand, the parameters associated with surface flooding (extension of flood areas, flow depth and velocity) can be used to estimate potential impacts on other strategic urban services such as surface traffic, the electrical system and the waste collection service.Proyecto RESCCUE (RESilience to cope with Climate Change in Urban arEas - a multisectorial approach focusing on water), financiado por el programa H2020 de la Unión Europea (Acuerdo No. 700174)Russo, B.; Velasco, M.; Monjo, R.; Martínez-Gomariz, E.; Sánchez, D.; Domínguez, JL.; Gabàs, A.... (2020). Evaluación de la resiliencia de los servicios urbanos frente a episodios de inundación en Barcelona. El Proyecto RESCCUE. Ingeniería del agua. 24(2):101-118. https://doi.org/10.4995/ia.2020.12179OJS101118242Ecologia Urbana. 2018. Pla Clima 2018-2030. Ajuntament de Barcelona.Evans, B. 2017. Deliverable 3.1. Selection of methods for quantification of impacts of identified hazards. Deliverable 3.1. RESCCUE Project. Grant Agreement No. 700174. Disponible en http://www.resccue.euEvans, B. 2019. Deliverable 3.4. Impact assessments of multiple hazards in case study areas. Deliverable 3.4. RESCCUE Project. Grant Agreement No. 700174. Disponible en http://www.resccue.euFederal Emergency Management Agency (FEMA). 2009. Multi-Hazard Loss Estimation Methodology, Flood Model: Hazus-MH MR4 Technical Manual. 2009th ed. Disponible en https://www.fema.gov/media-library-data/20130726-1820-25045-8292/hzmh2_1_fl_tm.pdf.Martínez-Gomariz, E., Gómez, M., Russo, B. 2016. Estabilidad de personas en flujos de agua. Ingeniería del agua, 20,(1), 43-58. https://doi.org/10.4995/ia.2016.4231Martínez-Gomariz, E., Gómez, M., Russo, B. 2017. A new experiments-based methodology to obtain the stability threshold for any real vehicle exposed to flooding. Urban Water Journal, 14(9), 930-939. https://doi.org/10.1080/1573062X.2017.1301501Martínez-Gomariz, E., Gómez, M., Russo, B. 2018a. Stability criteria for flooded vehicles: A state of the art review. Journal of Flood Risk Management, 11, S817-S826. https://doi.org/10.1111/jfr3.12262Martínez‐Gomariz, E., Gómez, M., Russo, B., Sánchez, P., Montes, J. A. 2018b. Methodology for the damage assessment of vehicles exposed to flooding in urban areas. Journal of Flood Risk Management, 12(3), e12475 (Early View). https://doi.org/10.1111/jfr3.12475Monjo R., Gaitán E., Pórtoles J., Ribalaygua J., Torres L. 2016. Changes in extreme precipitation over Spain using statistical downscaling of CMIP5 projections. International Journal of Climatology, 36, 757-769. https://doi.org/10.1002/joc.4380Monjo R., Paradinas C., Gaitán E., Redolat D., Paradinas C., Prado C., Portolés J., Torres L., Ribalaygua J. Russo B., Velasco M., Pouget L., Vela S., David M. L., Morais M., Ribalaygua J. 2018. Report on extreme events predictions. Deliverable 1.3 RESCCUE Project. Grant Agreement No. 700174. Disponible en http://www.resccue.euPenning-Rowsell, E., Johnson, C., Tunstall, S., Tapsell, S., Morris, J., Chatterton, J., Green, C. 2005. The benefits of flood and coastal risk management: A handbook of assessment techniques. North London Business Park, Oakleigh Road South, London, England: Flood Hazard Research Centre, Middlesex University Press.Pyatkova K., Chen A. S., Djordjevic S., Butler D., Vojinovic Z., Abebe Y. A., Hammond M. 2015. Flood Impacts on Road transportation Using Microscopic Traffic Modelling Technique [Conference]. SUMO User Conference.Reiter, P. 2000. International methods of Risk Analysis, Damage evaluation and social impact studies concerning Dam-Break accidents. EU-Project RESCDAM. Seinäjoki, Finlandia.Russo, B., Gómez, M., Macchione, F. 2013. Pedestrian hazard criteria for flooded urban areas. Nat Hazards, 69, 251-265. https://doi.org/10.1007/s11069-013-0702-2Russo B., Pouget L., Malgrat P., García J. 2011. Evaluación del impacto del cambio climático en un caso de estudio de Barcelona a través de una modelización 2D-1D del drenaje dual. JIA2011. Barcelona, España. ISBN: 13-978-84-615-4023-5.Russo B., Sunyer D., Velasco M., Djordjević S. 2015. Analysis of extreme flooding events through a calibrated 1D/2D coupled model: the case of Barcelona (Spain). Journal of Hydroinformatics, 17(3), 473-491. https://doi.org/10.2166/hydro.2014.063Russo B. 2018. Multi-hazards assessment related to water cycle extreme events for current scenario. Deliverable 2.4 RESCCUE Project. Grant Agreement No. 700174. Disponible en http://www.resccue.euRusso B. 2019. Multi-hazards assessment related to water cycle extreme events for future scenarios (Business As Usual). Deliverable 2.3 RESCCUE Project. Grant Agreement No. 700174. Disponible en http://www.resccue.euShand, T.D., Cox, R., Blacka, M.J., Smith G.P. 2011. Australian Rainfall and Runoff (AR&R). Revision Project 10: Appropriate Safety Criteria for Vehicles (Report Number: P10/S2/020).U.S. Army Corps of Engineers (USACE). 2009. Economic Guidance Memorandum, 09-04, Generic Depth-Damage Relationships for Vehicles. Washington, D.C, USAVelasco, M., Russo, B., Martínez, M., Malgrat, P., Monjo, R., Djordjevic, S., Fontanals, I., Vela, S., Cardoso, M.A., Buskute, A. 2018. Resilience to cope with climate change in urban areas-A multisectorial approach focusing on water-The RESCCUE project. Water, 10, 1356-1366. https://doi.org/10.3390/w1010135
Spin-glass like behavior in Rb2Fe1-xInxCl5·H2O solid solutions
Below Tc = 10.0 K undiluted Rb2FeCl5·H2O is a 3-D Heisenberg antiferromagnet possessing rather low magnetic anisotropy (α = 3.4×10-3). Dilutions of the above compound with the analogous isomorphic In derivative form a novel family of insulating spin-glasses of general formula Rb2Fe1-xInxCl5·H2O. Both in-phase (x′) and out-of-phase (x″) components of the ac magnetic susceptibility have been measured at zero (external) magnetic field and as a function of the frequency for different concentrations of the diamagnetic ion (x = 0.05, 0.1 and 0.3). Magnetization measurements after zero-field cooling and in field-cooling have also been used to characterize the spin-glass behavior of these solid solutions.The research has been supported by Grant CICYT MAT 88-0174 in Spain and by the Brazilian agencies CNPq, BID and FAPESP. The cooperative work has been supported by the “Programa de Cooperacion Cientifica Iberoamericana”.Peer Reviewe
Exploiting subproblem optimization in SAT-based MaxSAT algorithms
The Maximum Satisfiability (MaxSAT) problem is an optimization variant of the Satisfiability (SAT) problem. Several combinatorial optimization problems can be translated into a MaxSAT formula. Among exact MaxSAT algorithms, SAT-based MaxSAT algorithms are the best performing approaches for real-world problems. We have extended the WPM2 algorithm by adding several improvements. In particular, we show that by solving some subproblems of the original MaxSAT instance we can dramatically increase the efficiency of WPM2. This led WPM2 to achieve the best overall results at the international MaxSAT Evaluation 2013 (MSE13) on industrial instances. Then, we present additional techniques and heuristics to further exploit the information retrieved from the resolution of the subproblems. We exhaustively analyze the impact of each improvement what contributes to our understanding of why they work. This architecture allows to convert exact algorithms into efficient incomplete algorithms. The resulting solver had the best results on industrial instances at the incomplete track of the latest international MSE. © 2015, Springer Science+Business Media New York.Research partially supported by the Ministerio de Economía y Competividad research project TASSAT2: TIN2013-48031-C4-4-P and Google Faculty Research Award program.Peer Reviewe
Geologic framework of the Fang Hot Springs area with emphasis on structure, hydrology, and geothermal development, Chiang Mai Province, northern Thailand
Mortality reduction by post-dilution online-haemodiafiltration : A cause-specific analysis
Background. From an individual participant data (IPD) meta-analysis from four randomized controlled trials comparing haemodialysis (HD) with post-dilution online-haemodiafiltration (ol-HDF), previously it appeared that HDF decreases all-cause mortality by 14% (95% confidence interval 25; 1) and fatal cardiovascular disease (CVD) by 23% (39; 3). Significant differences were not found for fatal infections and sudden death. So far, it is unclear, however, whether the reduced mortality risk of HDF is only due to a decrease in CVD events and if so, which CVD in particular is prevented, if compared with HD. Methods. The IPD base was used for the present study. Hazard ratios and 95% confidence intervals for cause-specific mortality overall and in thirds of the convection volume were calculated using the Cox proportional hazard regression models. Annualized mortality and numbers needed to treat (NNT) were calculated as well. Results. Besides 554 patients dying from CVD, fatal infections and sudden death, 215 participants died from 'other causes', such as withdrawal from treatment and malignancies. In this group, the mortality risk was comparable between HD and ol-HDF patients, both overall and in thirds of the convection volume. Subdivision of CVD mortality in fatal cardiac, non-cardiac and unclassified CVD showed that ol-HDF was only associated with a lower risk of cardiac casualties [0.64 (0.61; 0.90)]. Annual mortality rates also suggest that the reduction in CVD death is mainly due to a decrease in cardiac fatalities, including both ischaemic heart disease and congestion. Overall, 32 and 75 patients, respectively, need to be treated by high-volume HDF (HV-HDF) to prevent one all-cause and one CVD death, respectively, per year. Conclusion. The beneficial effect of ol-HDF on all-cause and CVD mortality appears to be mainly due to a reduction in fatal cardiac events, including ischaemic heart disease as well as congestion. In HV-HDF, the NNT to prevent one CVD death is 75 per year
Mortality reduction by post-dilution online-haemodiafiltration : A cause-specific analysis
Background. From an individual participant data (IPD) meta-analysis from four randomized controlled trials comparing haemodialysis (HD) with post-dilution online-haemodiafiltration (ol-HDF), previously it appeared that HDF decreases all-cause mortality by 14% (95% confidence interval 25; 1) and fatal cardiovascular disease (CVD) by 23% (39; 3). Significant differences were not found for fatal infections and sudden death. So far, it is unclear, however, whether the reduced mortality risk of HDF is only due to a decrease in CVD events and if so, which CVD in particular is prevented, if compared with HD. Methods. The IPD base was used for the present study. Hazard ratios and 95% confidence intervals for cause-specific mortality overall and in thirds of the convection volume were calculated using the Cox proportional hazard regression models. Annualized mortality and numbers needed to treat (NNT) were calculated as well. Results. Besides 554 patients dying from CVD, fatal infections and sudden death, 215 participants died from 'other causes', such as withdrawal from treatment and malignancies. In this group, the mortality risk was comparable between HD and ol-HDF patients, both overall and in thirds of the convection volume. Subdivision of CVD mortality in fatal cardiac, non-cardiac and unclassified CVD showed that ol-HDF was only associated with a lower risk of cardiac casualties [0.64 (0.61; 0.90)]. Annual mortality rates also suggest that the reduction in CVD death is mainly due to a decrease in cardiac fatalities, including both ischaemic heart disease and congestion. Overall, 32 and 75 patients, respectively, need to be treated by high-volume HDF (HV-HDF) to prevent one all-cause and one CVD death, respectively, per year. Conclusion. The beneficial effect of ol-HDF on all-cause and CVD mortality appears to be mainly due to a reduction in fatal cardiac events, including ischaemic heart disease as well as congestion. In HV-HDF, the NNT to prevent one CVD death is 75 per year