Spanish version of the Coping Strategies Inventory

Introducción. En el presente trabajo acometimos la adaptación del Inventario de Estrategias de Afrontamiento (CSI) al ámbito español. Esta necesidad se justifica, por una parte, por la escasez y las limitaciones de los instrumentos disponibles en nuestro idioma, y por otra, por las excelentes potencialidades que ofrece el CSI. Método. Fue traducido y aplicado a una muestra de 337 personas adultas de características sociodemográficas diversas, recogida de forma incidental en actividades formativas en la provincia de Sevilla. Resultados. Los resultados mostraron unas excelentes propiedades psicométricas superando incluso las del estudio original: ocho factores explicaron un 61 % de la varianza con sólo 40 ítems (frente a los 72 que explicaban un 47% en el instrumento original) y obtuvieron coeficientes de consistencia interna entre 0,63 y 0,89. La validez convergente se comprobó utilizando las intercorrelaciones entre escalas y las correlaciones con disposiciones de personalidad (NEO-FFI) y eficacia percibida del afrontamiento. Conclusiones. El CSI se comportó de forma válida y fiable en la evaluación de la utilización de estrategias de afrontamiento en una amplia variedad de situaciones.Introduction. The aim of the present study was to adapt the Coping Strategies Inventory (CSI) to the Spanish setting. This need is justified on the one hand by the shortage and limitations of the instruments available in our language and, on the other, by the excellent potentialities that the CSI offers. Method. It was translated and applied to a sample of 337 adults, with diverse demographic characteristics, recruited from different teaching activities by the authors in the province of Seville (Spain). Results. The results showed excellent psychometric properties surpassing those of the original study: eight factors accounted for 61% of variance with only 40 items (as opposed to the 72 that accounted for 47% in the original study) and obtained Alpha coefficients between 0.63 and 0.89. The convergent validity was verified using intercorrelations between scales, correlations with personality dispositions (NEO-FFI) and with the coping efficacy. Discussion. The CSI was a valid and reliable measure of coping strategies used in many stressful situations

Personal Geographies in GIS: New Approaches to Analyse Accessibility to Public Services

This paper presents the results of two complementary studies undertaken in the city of Alcalá de Henares, Spain. The main objective was to analyse accessibility to public services from the users' personal circumstances and perception of the environment. The paper provides information on the methodology adopted to include cognitive distances and time budgets into a GIS database. It summarises both cartographic and numeric results and concludes with a discussion on future developments in this area. The main outcomes of the study include: (a) the demonstration that personal geographies can be handled and analysed using GIS technology, (b) a personal approach to the analysis of spatiotemporal accessibility, and (c) the development of a set of innovative cartographic representations

Optimization of the parallel and mild hybrid vehicle platforms operating under conventional and advanced combustion modes

[EN] The stringent regulations, increased global temperature and customer demand for high fuel economy have led to rapid developments of different alternative propulsion solutions in the last decade, with special attention to the electrified vehicles. The combination of electric machines with conventional powertrains allows to diversify the powertrain architectures. In addition, alternative combustion modes as reactivity controlled compression ignition (RCCI) have been shown to provide simultaneous ultra-low NOx and soot emissions with similar or better thermal efficiency than conventional diesel combustion (CDC). Therefore, the combination of both technologies creates a promising horizon to be implemented in commercial vehicles of the near future. In this work, experimental and numerical simulations were combined to study the potential of the parallel full hybrid electric vehicle (P2-FHEV) and mild hybrid vehicle (MHEV) to obtain lower fuel consumption and NOx emissions than a conventional powertrain in the Worldwide Harmonized Light Vehicles Cycle (WLTC). The hybrid vehicles are simulated with both CDC and diesel-gasoline RCCI combustion engines as power source. Each powertrain was optimized in terms of components (battery, electric motors...) capacity, internal combustion engine operative points, energy management strategy and gear ratios. The results show a significant fuel consumption reduction as the complexity of the hybrid system increases. The parallel architecture, which represents the most complex hybrid system tested in this work, allows obtaining a fuel consumption reduction of around 20% as compared to CDC. The dual-mode CDC-RCCI concept showed improvements in NOx and soot emissions with comparable values in terms of energy consumption and CO2 emissions than CDC. Additionally, the mild hybrid technology with the functionality of start-stop, torque assist and regenerative braking showed an acceptable balance between complexity and fuel consumption gain.The authors want to express their gratitude to General Motors Global Research & Development for providing the engine used to acquire the experimental data used in this investigation. The authors acknowledge FEDER and Spanish Ministerio de Economia y Competitividad for partially supporting this research through TRANCO project (TRA2017-87694-R). The authors also acknowledge the Universitat Politecnica de Valencia for partially supporting this research through Convocatoria de ayudas a Primeros Proyectos de Investigation (PAID-06-18).Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Martínez-Boggio, S. (2019). Optimization of the parallel and mild hybrid vehicle platforms operating under conventional and advanced combustion modes. Energy Conversion and Management. 190:73-90. https://doi.org/10.1016/j.enconman.2019.04.010S739019

Evaluation of Enzyme Additives on the Nutritional Use of Feeds with a High Content of Plant Ingredients for Mugil cephalus

The Mugilidae are a group of fish with a great interest for aquaculture due to their omnivorous profile, rapid growth, and resistance to environmental variations. The selection of feed ingredients for these species is currently focused on an extensive use of plant by-products, with this being limited by their content in anti-nutritive factors (mainly phytate and non-starch polysaccharides; NSPs). Nevertheless, specific enzymes can be used to counteract some of those negative effects. In the present study, the effect of pretreating two high-plant feeds with a mixture of enzymes (glucanases + phytase) on the digestive use of protein and phosphorus by juvenile mullets (Mugil cephalus) was assessed using both in vitro and in vivo assays. The enzymatic treatment significantly modified the potential bioavailability of some nutrients, such as a reduction of sugars, pentoses, and phytic phosphorus. Also, it increased the digestibility of protein in one of the feeds but reduced that of phosphorus in both of them. The potential usefulness of enzyme treatment and the information provided by the two types of assays are discusse

Emissions reduction from passenger cars with RCCI plug-in hybrid electric vehicle technology

[EN] Hybrid Electric Vehicles (HEVs) can be considered as a potential technology to promote the change from conventional mobility to e-mobility. However, the real benefits in terms of CO2 emissions depend on a great extent on their mode of use, vehicle design and electricity source. On the other hand, in the last few years, advanced combustion modes as Reactivity Controlled Compression Ignition (RCCI) showed great advantages in terms of NOx and soot emissions reduction. This paper has the purpose of assessing, through numerical simulations fed with experimental results, the potential of different hybrid vehicles when used together with a low temperature combustion mode. In particular, the dual-fuel Mild (MHEV), Full (FHEV) and Plug-in (PHEV) hybrid electric vehicles are tested and compared to the original equipment manufacturer (OEM) and the conventional dual-fuel powertrain, both no-Hybrid vehicles. The powertrains are optimized to meet the current European homologation legislation Worldwide Harmonized Light Vehicle Test Procedure (WLTP). After that, a deep analysis is performed in terms of performance and emissions. Lastly, a life-cycle analysis (LCA) is performed to evaluate the real potential of the different technologies. The results show that the PHEV has the highest benefits in terms of fuel consumption and engine-out emissions. With this technology, it is possible to achieve the 50 g/km CO2 target for the PHEVs with a medium battery size (15 kWh), while NOx and soot levels are under the Euro 6 limits. In addition, the RCCI technology shows great benefits to achieve the Euro 6 soot level for the other hybrid platforms. The LCA shows that the PHEVs can achieve 12% reduction of the total CO2 with respect to the FHEVs, and 30% with respect to the no-hybrid diesel platform.The authors acknowledge FEDER and Spanish Ministerio de Economia y Competitividad for partially supporting this research through TRANCO project (TRA2017-87694-R). The authors also acknowledge the Universitat Politecnica de Valencia for partially supporting this research through Convocatoria de ayudas a Primeros Proyectos de Investigacion (PAID-06-18).Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Martínez-Boggio, SD. (2020). Emissions reduction from passenger cars with RCCI plug-in hybrid electric vehicle technology. Applied Thermal Engineering. 164:1-17. https://doi.org/10.1016/j.applthermaleng.2019.114430S117164Rahman, S. M. A., Masjuki, H. H., Kalam, M. A., Abedin, M. J., Sanjid, A., & Sajjad, H. (2013). 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Well-to-Wheels Analysis of the Greenhouse Gas Emissions and Energy Use of Vehicles with Gasoline Compression Ignition Engines on Low Octane Gasoline-Like Fuel. SAE International Journal of Fuels and Lubricants, 9(3), 527-545. doi:10.4271/2016-01-2208Argon, A review of Battery Life-Cycle Analysis: State of Knowledge and Critical Needs, 2010.Millo, F., Ferraro, C. V., & Rolando, L. (2012). Analysis of different control strategies for the simultaneous reduction of CO2 and NOx emissions of a diesel hybrid passenger car. International Journal of Vehicle Design, 58(2/3/4), 427. doi:10.1504/ijvd.2012.047393Asghar, M., Bhatti, A. I., Ahmed, Q., & Murtaza, G. (2018). Energy Management Strategy for Atkinson Cycle Engine Based Parallel Hybrid Electric Vehicle. IEEE Access, 6, 28008-28018. doi:10.1109/access.2018.2835395Benajes, J., García, A., Monsalve-Serrano, J., & Martínez-Boggio, S. (2019). Optimization of the parallel and mild hybrid vehicle platforms operating under conventional and advanced combustion modes. Energy Conversion and Management, 190, 73-90. doi:10.1016/j.enconman.2019.04.010Talibi, M., Hellier, P., Watkinson, M., & Ladommatos, N. (2019). Comparative analysis of H2-diesel co-combustion in a single cylinder engine and a chassis dynamometer vehicle. International Journal of Hydrogen Energy, 44(2), 1239-1252. doi:10.1016/j.ijhydene.2018.11.092Benajes, J., García, A., Monsalve-Serrano, J., & Lago Sari, R. (2018). Fuel consumption and engine-out emissions estimations of a light-duty engine running in dual-mode RCCI/CDC with different fuels and driving cycles. Energy, 157, 19-30. doi:10.1016/j.energy.2018.05.144Bao, R., Avila, V., & Baxter, J. (2017). Effect of 48 V Mild Hybrid System Layout on Powertrain System Efficiency and Its Potential of Fuel Economy Improvement. SAE Technical Paper Series. doi:10.4271/2017-01-1175Liu, Z., Ivanco, A., & Filipi, Z. S. 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Thermal performance of lithium ion battery pack by using cold plate. Applied Thermal Engineering, 160, 114088. doi:10.1016/j.applthermaleng.2019.114088Moro, A., & Lonza, L. (2018). Electricity carbon intensity in European Member States: Impacts on GHG emissions of electric vehicles. Transportation Research Part D: Transport and Environment, 64, 5-14. doi:10.1016/j.trd.2017.07.012Shields, M. D., & Zhang, J. (2016). The generalization of Latin hypercube sampling. Reliability Engineering & System Safety, 148, 96-108. doi:10.1016/j.ress.2015.12.002García, A., Piqueras, P., Monsalve-Serrano, J., & Lago Sari, R. (2018). Sizing a conventional diesel oxidation catalyst to be used for RCCI combustion under real driving conditions. Applied Thermal Engineering, 140, 62-72. doi:10.1016/j.applthermaleng.2018.05.043Benajes, J., García, A., Monsalve-Serrano, J., & Sari, R. (2018). Potential of RCCI Series Hybrid Vehicle Architecture to Meet the Future CO2 Targets with Low Engine-Out Emissions. 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Análisis de contenido del estigma público sobre la violencia de pareja contra la mujer en una muestra universitaria española: Un estudio preliminar

Public stigma on intimate partner violence against women (IPVAW) is still present among university students and hinders victim recovery. The aims were to: 1) Analyze public stigma in university students using content scales found in the literature, distinguishing between general negative attitudes towards IPVAW and those when asked about a known situation of violence, and 2) Determine the reliability of those scales. A sample of 37 students (age, M=25.54; SD=3.44) at the University of Seville completed a survey based on the selected content scales. Response content was analyzed. Attitudes were related to myths exonerating the abuser, the majority belief that victims' actions for recovery were detachment strategies, and a catastrophic perception of the consequences of violence. Attitudes changed after knowing a victim. Most scales were reliable (Kappa > 0.7). Stigma toward IPVAW was present, but to a lesser extent when the situation of violence was known. The implications of this study and future lines of research were discussed.El estigma público en violencia de pareja contra la mujer entre estudiantado universitarios sigue presente y dificulta la recuperación de las víctimas. Los objetivos fueron: (a) Analizar el estigma público en alumnado universitario a través de escalas de contenido extraídas de la literatura, distinguiendo entre las actitudes negativas hacia la violencia de pareja contra la mujer de forma general y cuando se les preguntaba por una situación de violencia conocida, y (b) Determinar la fiabilidad de dichas escalas. 37 estudian-tes (edad, M=25.54; DT=3.44) de la Universidad de Se-villa rellenaron una encuesta elaborada a partir de las es-calas. Se aplicó un análisis de contenido de las respuestas. Las actitudes se relacionaban con mitos sobre el maltratador que le exoneran, la creencia mayoritaria de que las acciones de recuperación de las víctimas se reducen a estrategias de desprendimiento y una percepción catastrofista de las consecuencias de la violencia. Las actitudes disminuían tras conocer a una víctima. La mayoría de las escalas fueron fiables (Kappa>.7). El estigma estuvo presente, pero en menor medida hacia situaciones de violencia conocidas. Se debatieron las implicaciones de este estudio y futuras líneas de investigación

Gaseous emissions and particle size distribution of dual-mode dual-fuel diesel-gasoline concept from low to full load

[EN] Low temperature combustion concepts are in focus of study nowadays as a method to avoid the NOx-soot trade-off existing with conventional diesel combustion. One of the most promising strategy is known as reactivity controlled compression ignition because of its high thermal efficiency and the ultra-low nitrogen oxides and soot emissions. However, this concept presents several challenges such as the high levels of carbon monoxide and unburned hydrocarbons promoted at low load and unacceptable levels of pressure rise rate at high load. Therefore, to mitigate these shortcomings the dual-mode dual-fuel concept, combining reactivity controlled compression ignition and diffusive dual-fuel diesel-gasoline combustion, has been developed. Total number of particles is also limited by the emission standards. Previous studies focused in particles emissions carried out by the research community present particle size distribution, composition and mass of the particles on reactivity controlled compression ignition combustion mode. Additional studies were carried out in order to identify the components of these particles, being partially formed of volatiles, and reflects that particles are smaller than at conventional diesel combustion, presenting higher number of particles from nucleation mode than from accumulation mode. Dual-Mode Dual-Fuel concept may present a different behavior for particle distribution with respect to the conventional diesel combustion or the traditional low temperature concepts due to the nature of the particles. The objective of the present study is to measure the particle size distribution as well as gaseous emissions of this new Dual-Mode Dual-Fuel concept from low load to full load for a representative engine speed of 1200 rpm. Main results of this study suggest that Dual-Mode Dual-Fuel concept promotes higher quantity of particles than conventional diesel combustion despite of providing less smoke. In addition, nucleation mode particles dominate the particle size distribution for the new combustion concept at low load and moves towards accumulation mode domination at full load. (C) 2017 Elsevier Ltd. All rights reserved.This investigation has been funded by VOLVO Group Trucks Technology. The authors also acknowledge the Spanish economy and competitiveness ministry for partially supporting this research (HiReCo TRA2014-58870-R). The predoctoral contract of the author V. Boronat (FPI-S2-2017-2882) is granted by the Programa de Apoyo para la Investigacion y Desarrollo (PAID) of the Universitat Politecnica de Valencia. The author J. Monsalve-Serrano acknowledges the financial support from the Universitat Politecnica de Valencia under the grant "Ayudas Para la Contratacion de Doctores para el Acceso al Sistema Espahol de Ciencia, Tecnologia e Innovacion".Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Boronat-Colomer, V. (2017). Gaseous emissions and particle size distribution of dual-mode dual-fuel diesel-gasoline concept from low to full load. Applied Thermal Engineering. 120:138-149. https://doi.org/10.1016/j.applthermaleng.2017.04.005S13814912

Surrogate Fuel Formulation to Improve the Dual-Mode Dual-Fuel Combustion Operation at Different Operating Conditions

[EN] Dual-mode dual-fuel combustion is a promising combustion concept to achieve the required emissions and CO2 reductions imposed by the next standards. Nonetheless, the fuel formulation requirements are stricter than for the single-fuel combustion concepts as the combustion concept relies on the reactivity of two different fuels. This work investigates the effect of the low reactivity fuel sensitivity (S=RON-MON) and the octane number at different operating conditions representative of the different combustion regimes found during the dual-mode dual-fuel operation. For this purpose, experimental tests were performed using a PRF 95 with three different sensitivities (S0, S5 and S10) at operating conditions of 25% load/950 rpm, 50%/1800 rpm and 100%/2200 rpm. Moreover, air sweeps varying ±10% around a reference air mass were performed at 25%/1800 rpm and 50%/1800 rpm. Conventional diesel fuel was used as high reactivity fuel in all the cases. Moreover, commercial 95 RON gasoline was used as reference to compare the different TRFs. The engine settings were managed to adjust the rate of heat release to that found with 95 RON gasoline. To do this, a quality index imposing a maximum deviation of 5% point-to-point between the HRR curves from both fuels was defined. The results suggest that PRF 95 with S0 has the most similar behavior compared to conventional 95 RON gasoline whatever the engine load. As the engine load increases, the sensitivity effect is more noticeable and iso-HRR operation was only possible for S0. At low and medium load, the TRFs present similar engine-out emissions with equal fuel consumption. At full load, the NOx emissions are increased with respect to the reference 95 RON gasoline without fuel consumption benefits. The results from the air variation for the different octane numbers demonstrated that the greatest differences are obtained for low air mass (i.e, higher EGR). In addition, the decrease of the octane number limits the maximum air increase due to the pressure gradients, requiring modifications in the engine settings that increase the soot formation.The authors thanks VOLVO Group Trucks Technology and ARAMCO Overseas Company for supporting this research. The authors also acknowledge FEDER and Spanish Ministerio de Economía y Competitividad for partially supporting this research through TRANCO project (TRA2017-87694-R) and the Universitat Politècnica de València for partially supporting this research through Convocatoria de ayudas a Primeros Proyectos de Investigación (PAID-06-18). The author R. Sari acknowledges the financial support from the Spanish ministry of science innovation and universities under the grant ¿Ayudas para contratos predoctorales para la formación de doctores¿ (PRE2018-085043).Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Lago-Sari, R. (2020). Surrogate Fuel Formulation to Improve the Dual-Mode Dual-Fuel Combustion Operation at Different Operating Conditions. SAE International. 1-13. https://doi.org/10.4271/2020-01-2073S11

Particulates Size Distribution of Reactivity Controlled Compression Ignition (RCCI) on a Medium-Duty Engine Fueled with Diesel and Gasoline at Different Engine Speeds

[EN] This work investigates the particulates size distribution of reactivity controlled compression ignition combustion, a dual-fuel concept which combines the port fuel injection of low-reactive/gasoline-like fuels with direct injection of highly reactive/diesel-like fuels. The particulates size distributions from 5-250 nm were measured using a scanning mobility particle sizer at six engine speeds, from 950 to 2200 rpm, and 25% engine load. The same procedure was followed for conventional diesel combustion. The study was performed in a single-cylinder engine derived from a stock medium-duty multi-cylinder diesel engine of 15.3:1 compression ratio. The combustion strategy proposed during the tests campaign was limited to accomplish both mechanical and emissions constraints. The results confirms that reactivity controlled compression ignition promotes ultra-low levels of nitrogen oxides and smoke emissions in the points tested. However, in spite of having similar or lower smoke emissions, the number of particles in some conditions is higher for the reactivity controlled compression ignition than for conventional diesel combustion. Nucleation mode dominates the particle formation for the reactivity controlled compression ignition mode, while accumulation mode dominates the particle formation for conventional diesel combustion. Thus, it is confirmed that the smoke measurement in filter smoke number units cannot be used to correlate the total particle mass for the reactivity controlled compression ignition mode, as typically done for conventional diesel combustion.This investigation has been funded by VOLVO Group Trucks Technology. The authors also acknowledge the Spanish economy and competitiveness ministry for partially supporting this research (HiReCo TRA2014-58870-R). The predoctoral contract of the author V. Boronat (FPI-S2-2017-2882) is granted by the Programa de Apoyo para la Investigacion y Desarrollo (PAID) of the Universitat Politecnica de Valencia. The author J. Monsalve-Serrano acknowledges the financial support from the Universitat Politecnica de Valencia under the grant "Ayudas Para la Contratacion de Doctores para el Acceso al Sistema Espanol de Ciencia, Tecnologia e Innovacion".Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Boronat-Colomer, V. (2017). Particulates Size Distribution of Reactivity Controlled Compression Ignition (RCCI) on a Medium-Duty Engine Fueled with Diesel and Gasoline at Different Engine Speeds. SAE International Journal of Engines. 10(5):2382-2391. https://doi.org/10.4271/2017-24-0085S2382239110

Fuel consumption and engine-out emissions estimations of a light-duty engine running in dual-mode RCCI/CDC with different fuels and driving cycles

[EN] This work compares the performance and emissions of two dual-mode combustion concepts over different driving cycles by means of vehicle systems simulations. The dual-mode concept relies on switching between the dual-fuel concept known as reactivity controlled compression ignition (RCCI) and conventional diesel combustion (CDC) to cover the whole engine map. The experimental RCCI maps obtained with diesel-E85 and diesel-gasoline used as inputs to perform the simulations were obtained in a high compression ratio light-duty diesel engine (17.1:1) following the same mapping procedure in both cases. The driving cycles simulated to perform the comparison were the Real Driving Emissions cycle (Europe), Worldwide harmonized Light vehicles Test Cycle (Europe), Federal Test Procedure FTP-75 (United States) and JC08 (Japan). The results show that the dual-mode concept has potential to be implemented in flexible-fuel vehicles. Using gasoline as low reactivity fuel (LRF) for RCCI, the vehicle mileage would be equal to CDC, but having reductions in NOx and soot emissions of 16% and 50%, respectively, along the RDE cycle. Using E85 instead of gasoline, the reductions in NOx and soot emissions increase up to 50% and 85%, respectively, but in this case promoting higher thermal efficiency than CDC. (C) 2018 Elsevier Ltd. All rights reserved.The authors gratefully acknowledge General Motors Global Research & Development for providing the engine used to acquire the experimental data shown in this investigation. The authors also acknowledge FEDER and Spanish Ministerio de Economia y Competitividad for partially supporting this research through HiReCo project (TRA2014-58870-R).Benajes, J.; García Martínez, A.; Monsalve-Serrano, J.; Lago-Sari, R. (2018). Fuel consumption and engine-out emissions estimations of a light-duty engine running in dual-mode RCCI/CDC with different fuels and driving cycles. Energy. 157:19-30. https://doi.org/10.1016/j.energy.2018.05.144S193015