Audiomagnetotelluric investigation of seawater intrusion using 2-D inversion of invariant impedances

An audio-magnetotelluric survey was conducted to estimate the extension of the seawater intrusion in a coastal aquifer, in Ensenada, Baja California, México. The survey consisted of 134 closely spaced sites along three profiles 5 to 6 km long. The four elements of the impedance tensor were measured at every observation site and used to estimate the series and parallel (s-p) invariant impedances. 2-D resistivity models were obtained along each profile using a Gauss-Newton regularized inversion process. The seawater intrusion is clearly shown in the resulting models as highly conductive anomalies. In some places, the resistivity models show the bedrock and the basement faults in good agreement with structures interpreted from gravity and magnetic modeling. Based on the information provided by the resistivity models and using the available hydrogeologic information, we used Archie's law in an attempt to gain insights about porosity and TDS distributions in the aquifer. Porosity values between 15 and 25% near the surface reasonably predict the TDS values observed in several shallow wells in the area. TDS values range from 40 g/l typical for seawater to 1 g/l in the eastern edge of the basin, 4 km Hawai from the coastline. The best conditions were found in Profile 2, were the resistivity model predicts TDS values close to 1 g/l below 100 m depth at sites located further than 1 km from the coast. The above results show that s-p invariant impedances produced geologically plausible resistivity models. Hence, they might be a convenient set of magnetotelluric responses to be used for routine 2-D inversion of AMT data

Una nova necròpoli tumular en la Foia de Zucaina: Peñas de Villanueva (Zucaina, Alt Millars)

Resultats preliminars de la campanya d’excavació del 2014 en l’àrea de la necròpoli tumular Las Peñas de Villanueva. L’aspecte més rellevant d’aquesta campanya ha estat fonamentalment la localització d’una agrupació tumular que consta de dos túmuls.Preliminary results of the 2014 campaign of excavation in the area of the burial necropolis of Las Peñas de Villanueva. The most relevant aspect of this campaign has primarily been the location of a burial group consisting of two burial mounds

The coach-athlete relationship in basketball : analysis of the antecedents, components and outcomes

The aim of the study was to examine the coach-athlete relationship by analyzing the determinants of the quality of that relationship, the components emerged from previous constraints and the outcomes of the relationship. We accomplished a qualitative study using semistructured in-depth interviews with a total of 4 dyads (2 coaches and 4 players) selected deliberately. The data obtained suggested that the coach-athlete relationship in basketball is organized into three layers: a) relationship antecedent variables (coach's and athlete's behaviour and values wanted), b) components (behaviours, feelings, cognitions, improvement and maintenance strategies, and management of differences) and c) the consequences or outcomes (the coach and the player). In conclusion, we found that the different antecedents determine the components of the relationship, generating, in the case of positive relationships, satisfaction, wellbeing and performance, representing a personal and professional growth in both members of the dyad

Analysis of low-pressure exhaust gases recirculation transport and control in transient operation of automotive diesel engines

[EN] The objective of the study is to determine the behavior of the low pressure exhaust gas recirculation (LP EGR) transport phenomena in the intake manifold during engine transient operation. The investigation also analyzes the influence of the propagation of the pressure waves in the intake manifold on the engine performance. In this sense, there is a clear trade-off: long intake lines improve the engine volumetric efficiency at low engine speeds but delay the EGR transport in the system. The experiments were performed on a test bench with a 1.6 liter Euro-5 specification diesel engine. A CO2 fast tracking measurement device was setup and placed in two locations in the intake line in order to track the EGR transport in transient operation. The CO2 concentration is acquired with crank-angle resolution. Three different engine transients at constant engine speed were studied. They are extreme and worst-case scenarios in driving situations: (i) from low load to full load, (ii) from full load to low load, and (iii) from low load to medium load. In this way, it is possible to observe the behavior of the engine when: (i) leaving the EGR zone, (ii) entering into the EGR zone, and (iii) changing operating point without leaving the EGR zone. A consistent methodology that combines experimental results and a 1D model capable to predict the behavior of the engine was developed. The results obtained in this investigation show a relevant phenomenon: depending on the synchronization of the EGR and Exhaust Throttle (ET) valves, an overshoot occurs when the engine enters into EGR zone. In this study, the results show the importance of the synchronization of the valves that control the EGR strategy. Comparisons between measured and modeled CO2 concentrations lead to conclude that the EGR transport during engine transient operation is correctly predicted within a 1D engine code.Luján, JM.; Climent, H.; Arnau Martínez, FJ.; Miguel-García, J. (2018). Analysis of low-pressure exhaust gases recirculation transport and control in transient operation of automotive diesel engines. Applied Thermal Engineering. 137:184-192. https://doi.org/10.1016/j.applthermaleng.2018.03.085S18419213

Influence of ambient temperature on diesel engine raw pollutants and fuel consumption in different driving cycles

This is the author s version of a work that was accepted for publication in International Journal of Engine Research. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published as https://doi.org/10.1177/1468087418792353[EN] The effect of low ambient temperature on diesel raw pollutant emissions is analysed in two different driving cycles: NEDC and WLTC. The study is focused on hydrocarbons, carbon monoxide, nitrogen oxides and fuel consumption. Tests are conducted at cold start in a HSDI light-duty diesel engine with two levels of ambient temperature: 20 degrees C and -7 degrees C. Results showed a general detriment of pollutant emissions and break thermal efficiency at low ambient temperatures. NOx is increased around 250% in both cycles when running at low temperatures. Effect on hydrocarbons is more noticeable in the NEDC, where it rises in 270%, compared with the 150% of increase in the WLTC. In the case of carbon monoxide, uncorrelated tendencies are observed between both driving cycles. Concerning the NEDC, carbon monoxide emissions increase up to 125%, while at the WLTC, they are reduced up to 20%. Finally, from the point of view of the thermal efficiency, a reduction of nearly 10% in the NEDC is observed. However, no fuel penalty is spotted regarding the WLTC.The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: The authors acknowledge the 'Apoyo para la investigacion y Desarrollo (PAID)', grant for doctoral studies (FPI S1 2015 2512), of Universitat Politecnica de Valencia.Luján, JM.; Climent, H.; Ruiz-Rosales, S.; Moratal, A. (2019). Influence of ambient temperature on diesel engine raw pollutants and fuel consumption in different driving cycles. International Journal of Engine Research. 20(8-9):877-888. https://doi.org/10.1177/1468087418792353S877888208-9Reşitoğlu, İ. A., Altinişik, K., & Keskin, A. (2014). The pollutant emissions from diesel-engine vehicles and exhaust aftertreatment systems. Clean Technologies and Environmental Policy, 17(1), 15-27. doi:10.1007/s10098-014-0793-9Tan, Q., & Hu, Y. (2016). A study on the combustion and emission performance of diesel engines under different proportions of O2 & N2 & CO2. Applied Thermal Engineering, 108, 508-515. doi:10.1016/j.applthermaleng.2016.07.151Torregrosa, A. J., Olmeda, P., Martín, J., & Degraeuwe, B. (2006). Experiments on the influence of inlet charge and coolant temperature on performance and emissions of a DI Diesel engine. Experimental Thermal and Fluid Science, 30(7), 633-641. doi:10.1016/j.expthermflusci.2006.01.002Torregrosa, A. J., Broatch, A., Olmeda, P., & Romero, C. (2008). Assessment of the influence of different cooling system configurations on engine warm-up, emissions and fuel consumption. International Journal of Automotive Technology, 9(4), 447-458. doi:10.1007/s12239-008-0054-1Weilenmann, M., Favez, J.-Y., & Alvarez, R. (2009). Cold-start emissions of modern passenger cars at different low ambient temperatures and their evolution over vehicle legislation categories. Atmospheric Environment, 43(15), 2419-2429. doi:10.1016/j.atmosenv.2009.02.005Li, Q., Shayler, P., McGhee, M., & La Rocca, A. (2016). The initiation and development of combustion under cold idling conditions using a glow plug in diesel engines. International Journal of Engine Research, 18(3), 240-255. doi:10.1177/1468087416652266Tauzia, X., Maiboom, A., Karaky, H., & Chesse, P. (2018). Experimental analysis of the influence of coolant and oil temperature on combustion and emissions in an automotive diesel engine. International Journal of Engine Research, 20(2), 247-260. doi:10.1177/1468087417749391Ludykar, D., Westerholm, R., & Almén, J. (1999). Cold start emissions at +22, −7 and −20°C ambient temperatures from a three-way catalyst (TWC) car: regulated and unregulated exhaust components. Science of The Total Environment, 235(1-3), 65-69. doi:10.1016/s0048-9697(99)00190-4Weilenmann, M., Soltic, P., Saxer, C., Forss, A.-M., & Heeb, N. (2005). Regulated and nonregulated diesel and gasoline cold start emissions at different temperatures. Atmospheric Environment, 39(13), 2433-2441. doi:10.1016/j.atmosenv.2004.03.081Dardiotis, C., Martini, G., Marotta, A., & Manfredi, U. (2013). Low-temperature cold-start gaseous emissions of late technology passenger cars. Applied Energy, 111, 468-478. doi:10.1016/j.apenergy.2013.04.093Pavlovic, J., Marotta, A., & Ciuffo, B. (2016). CO2 emissions and energy demands of vehicles tested under the NEDC and the new WLTP type approval test procedures. Applied Energy, 177, 661-670. doi:10.1016/j.apenergy.2016.05.110Tsokolis, D., Tsiakmakis, S., Dimaratos, A., Fontaras, G., Pistikopoulos, P., Ciuffo, B., & Samaras, Z. (2016). Fuel consumption and CO2 emissions of passenger cars over the New Worldwide Harmonized Test Protocol. Applied Energy, 179, 1152-1165. doi:10.1016/j.apenergy.2016.07.091Giakoumis, E., & Zachiotis, A. (2017). Investigation of a Diesel-Engined Vehicle’s Performance and Emissions during the WLTC Driving Cycle—Comparison with the NEDC. Energies, 10(2), 240. doi:10.3390/en10020240Myung, C.-L., Jang, W., Kwon, S., Ko, J., Jin, D., & Park, S. (2017). Evaluation of the real-time de-NO x performance characteristics of a LNT-equipped Euro-6 diesel passenger car with various vehicle emissions certification cycles. Energy, 132, 356-369. doi:10.1016/j.energy.2017.05.089Marotta, A., Pavlovic, J., Ciuffo, B., Serra, S., & Fontaras, G. (2015). Gaseous Emissions from Light-Duty Vehicles: Moving from NEDC to the New WLTP Test Procedure. Environmental Science & Technology, 49(14), 8315-8322. doi:10.1021/acs.est.5b01364Luján, J. M., Climent, H., García-Cuevas, L. M., & Moratal, A. (2018). Pollutant emissions and diesel oxidation catalyst performance at low ambient temperatures in transient load conditions. Applied Thermal Engineering, 129, 1527-1537. doi:10.1016/j.applthermaleng.2017.10.138Ko, J., Jin, D., Jang, W., Myung, C.-L., Kwon, S., & Park, S. (2017). Comparative investigation of NOx emission characteristics from a Euro 6-compliant diesel passenger car over the NEDC and WLTC at various ambient temperatures. Applied Energy, 187, 652-662. doi:10.1016/j.apenergy.2016.11.105Armas, O., García-Contreras, R., & Ramos, A. (2016). On-line thermodynamic diagnosis of diesel combustion process with paraffinic fuels in a vehicle tested under NEDC. Journal of Cleaner Production, 138, 94-102. doi:10.1016/j.jclepro.2016.01.023Robinson, K., Ye, S., Yap, Y., & Kolaczkowski, S. T. (2013). Application of a methodology to assess the performance of a full-scale diesel oxidation catalyst during cold and hot start NEDC drive cycles. Chemical Engineering Research and Design, 91(7), 1292-1306. doi:10.1016/j.cherd.2013.02.022Konstantas, G., & Stamatelos, A. (2004). Quality assurance of exhaust emissions test data. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 218(8), 901-914. doi:10.1243/0954407041581075Pakko, J. D. (2009). Reconstruction of Time-Resolved Vehicle Emissions Measurements by Deconvolution. SAE International Journal of Fuels and Lubricants, 2(1), 697-707. doi:10.4271/2009-01-1513Flores, B. E. (1986). A pragmatic view of accuracy measurement in forecasting. Omega, 14(2), 93-98. doi:10.1016/0305-0483(86)90013-7Kandylas, I. P., Stamatelos, A. M., & Dimitriadis, S. G. (1999). Statistical uncertainty in automotive emissions testing. Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, 213(5), 491-502. doi:10.1243/0954407991527053Sileghem, L., Bosteels, D., May, J., Favre, C., & Verhelst, S. (2014). Analysis of vehicle emission measurements on the new WLTC, the NEDC and the CADC. Transportation Research Part D: Transport and Environment, 32, 70-85. doi:10.1016/j.trd.2014.07.008Stefanopoulou, A. G., Kolmanovsky, I., & Freudenberg, J. S. (2000). Control of variable geometry turbocharged diesel engines for reduced emissions. IEEE Transactions on Control Systems Technology, 8(4), 733-745. doi:10.1109/87.852917Control of diesel engines. (1998). IEEE Control Systems, 18(5), 53-71. doi:10.1109/37.722253Peng, H., Cui, Y., Shi, L., & Deng, K. (2008). Effects of exhaust gas recirculation (EGR) on combustion and emissions during cold start of direct injection (DI) diesel engine. Energy, 33(3), 471-479. doi:10.1016/j.energy.2007.10.014Bermúdez, V., Lujan, J. M., Pla, B., & Linares, W. G. (2011). Effects of low pressure exhaust gas recirculation on regulated and unregulated gaseous emissions during NEDC in a light-duty diesel engine. Energy, 36(9), 5655-5665. doi:10.1016/j.energy.2011.06.061Wang, S., Zhu, X., Somers, L. M. T., & de Goey, L. P. H. (2017). Effects of exhaust gas recirculation at various loads on diesel engine performance and exhaust particle size distribution using four blends with a research octane number of 70 and diesel. Energy Conversion and Management, 149, 918-927. doi:10.1016/j.enconman.2017.03.087Li, X., Xu, Z., Guan, C., & Huang, Z. (2014). Impact of exhaust gas recirculation (EGR) on soot reactivity from a diesel engine operating at high load. Applied Thermal Engineering, 68(1-2), 100-106. doi:10.1016/j.applthermaleng.2014.04.02

Diseño y propuesta de un plan de gestión para mejora de la eficiencia energética eléctrica en la empresa avícola Yugoslavia S.A.C.

RESUMEN El presente estudio propone un plan de gestión para mejorar la eficiencia energética eléctrica en una planta de Alimentos Balanceados, cuyas acciones propuestas permitirán optimizar el uso del recurso energético y generar ahorros económicos a la empresa. El estudio pretende buscar la competitividad basada en la gestión de la energía eléctrica. Para ello, es necesario realizar un diagnóstico energético eléctrico en las instalaciones de la planta, determinándose de esta manera acciones a ejecutar sin y con inversión. Dentro de las acciones a considerar, se demuestra los ahorros y beneficios logrados por: gestión tarifaria de la energía eléctrica, corrección de factor de potencia, compensación de la energía reactiva excesiva, implementación de líneas de distribución eficientes, implementación de luminarias eficientes, empleo de motores de alta eficiencia. Los resultados obtenidos en la investigación se lograron a través de criterios técnicos de ingeniería, siendo necesaria también la evaluación económica mediante la aplicación de herramientas financieras como el VAN, TIR, B/C, que nos permiten evaluar la rentabilidad del proyecto. De implementarse las propuestas del presente estudio, se estima un ahorro económico de S/. 388 623.44 nuevos soles en el mediano plazo (2011- 2014).ABSTRACT This study proposes a management plan to improve electrical energy efficiency in Feed Mills, which proposed actions will optimize resource use and generate cost savings to the company. The study aims to look for competitiveness based on the management of electrical energy. For this it is necessary to diagnose electrical power plant facilities, thus determining actions to be taken with and without investment. Among the actions to be considered, it shows the savings and benefits achieved by management of the electricity pricing, demand management, power factor correction, reactive power compensation excessive, implementation of efficient lighting, you light deployment efficient use of energy efficient motors. The research results were achieved through engineering technical criteria, also be necessary the economic evaluation by the application of financial tools such as VANE, TIRE, B/C, allowing us to evaluate the profitability of the project. If implemented the proposals in this study estimates a cost savings of S/.388623.44 in the medium term (2011-2014)

Switching strategy between HP (high pressure)- and LPEGR (low pressure exhaust gas recirculation) systems for reduced fuel consumption and emissions

EGR (Exhaust gas recirculation) plays a major role in current Diesel internal combustion engines as a cost-effective solution to reduce NO emissions. EGR systems will suffer a significant evolution with the introduction of NO after-treatment and the proliferation of more complex EGR architectures such as low pressure EGR or dual EGR. In this paper the combination of HPEGR (high pressure EGR) LPEGR (low pressure EGR) is presented as a method to minimise fuel consumption with reduced NOx emissions. Particularly, the paper proposes to switch between HPEGR and LPEGR architectures depending on the engine operating conditions in order to exploit the potential of both systems. In this sense, given a driving cycle, in the case at hand the NEDC, the proposed strategy seeks the EGR layout to use at each instant of the cycle to minimise the fuel consumption such that NO emissions are kept below a certain limit. The experimental results obtained show that combining both EGR systems sequentially along the NEDC allows to keep NO emission below a much lower limit with minimum fuel consumption.This work has been partially supported by Ministerio de Ciencia y Tecnologia through Project INNPACTO EGRCOEN.Lujan Martinez, JM.; Guardiola García, C.; Pla Moreno, B.; Reig, A. (2015). Switching strategy between HP (high pressure)- and LPEGR (low pressure exhaust gas recirculation) systems for reduced fuel consumption and emissions. Energy. 90:1790-1798. doi:10.1016/j.energy.2015.06.138S179017989

Career transition from junior to senior in basketball players

The purpose of the study was to investigate what factors affect basketball players in the transition from junior and amateur to senior and professional sport respectively. The study was a qualitative research which uses a semi-structured interview to get the data. There were interviewed five Spanish basketball players who were starting playing in a team of Basketball Club Association (C.B.A.). The results showed that the participants face several changes both in the sport and in the life outside sport. At the same time, the results indicated the existence of several coping strategies that help the player in his career transition

Técnicas de aprendizaje computacional aplicadas a la fotovoltaica

[ESP] En este artículo mostramos los resultados de la aplicación de varios métodos de aprendizaje computacional sobre datos procedentes de una instalación fotovoltaica de 222kWp de CdTe. Los datos de uno de los 30 grupos de módulos han sido estudiados en profundidad para predecir el estado en que se encuentra cuando el rendimiento es bajo: afectado por sombra fija, por sombra variable, los módulos están sucios, error ajeno a dichas circunstancias, etc. o bien identificar que está generando electricidad de forma adecuada.Asociación de Jóvenes Investigadores de Cartagena, (AJICT). Universidad Politécnica de Cartagena. Escuela Técnica Superior de Ingeniería Industrial UPCT, (ETSII). Escuela Técnica Superior de Ingeniería Agronónica, (ETSIA), Escuela Técnica Superior de Ingeniería de Telecomunicación (ETSIT). Escuela de Ingeniería de Caminos, Canales, y Puertos y de Ingeniería de Minas, (EICM). Fundación Séneca, Agencia Regional de Ciencia y Tecnología. Parque Tecnológico de Fuente Álamo. Grupo Aquiline

Prevalencia de las alteraciones del metabolismo óseo-mineral asociadas a enfermedad renal crónica no en diálisis

Background: chronic kidney disease (CKD) is a public health problem, and bone mineral metabolism disorder is one of its main complications that directly contributes to morbidity and mortality. Several previous studies have shown an increase in its prevalence as the glomerular filtration rate (GFR) decreases, however, we do not have data from our country or Latin America. Methods: We conducted a unicentric cross-sectional study in a nephrology consultation service in adults with CKD G1 to 5 who were not in renal replacement therapy, evaluated between January 2014 and March 2015. Data collection was performed with an instrument predefined that included demographic data, alterations of the mineral and bone metabolism parameters, and their management. Results: 2026 patients were included, of whom 1756 had parathyroid hormone measurement, the average age was 74 years, 62% were women. The distribution by degrees of CKD was: G1: 4.9%, G2: 22.8%, G3: 57.4%, G4: 12.5% and G5: 2.4%. The main causes were hypertensive and diabetic nephropathy. We found vitamin D deficiency in 78.16%, secondary hyperparathyroidism in 63.67% and hyperphosphatemia in 12.38%, with an increase in prevalence as GFR worsened. Conclusions: We found that mineral and bone metabolism alterations are frequent in patients with chronic kidney disease and start from early stages, as has been demonstrated in other studies. We believe that these results will lead to new management investigations in patients with CKD.Introducción: la enfermedad renal crónica (ERC) es un problema de salud pública, siendo el trastorno del metabolismo óseo mineral una de sus principales complicaciones y que contribuye directamente a la morbilidad y mortalidad. Varios estudios previos han demostrado un aumento de su prevalencia a medida que disminuye la tasa de filtración glomerular (TFG), sin embargo, no contamos con datos en nuestro país ni en América Latina. Métodos: realizamos un estudio transversal unicéntrico en un servicio de consulta de nefrología, en adultos con ERC G1 a 5 que no estuvieran en terapia de reemplazo renal, evaluados entre enero de 2014 y marzo de 2015. La recolección de datos se realizó con un instrumento predefinido que incluía datos demográficos, alteraciones de los parámetros del metabolismo mineral y óseo, y su manejo. Resultados: se incluyeron 2026 pacientes, de los cuales 1756 tenían medición de hormona paratiroidea, la edad promedio fue 74 años, el 62 % eran mujeres. La distribución por grados de ERC fue: G1:4,9 %, G2:22,8 %, G3: 57,4 %, G4: 12,5 % y G5:2,4 %. Las principales causas fueron la nefropatía hipertensiva y diabética. Encontramos deficiencia de vitamina D en el 78,16 %, hiperparatiroidismo secundario en el 63,67 % e hiperfosfatemia en el 12,38 %, con aumento de la prevalencia a medida que la TFG empeoraba. Conclusiones: encontramos que las alteraciones del metabolismo mineral y óseo son frecuentes en los pacientes con enfermedad renal crónica e inician desde estadios tempranos, como se ha demostrado en otros estudios. Consideramos que estos resultados llevarán a nuevas investigaciones de manejo en pacientes con ERC