Functional Value of Amaranth as Applied to Sports Nutrition

Amaranth can be beneficial to health and sports, with multiple applications owing to varied concentration of phytochemical; the concentration of these compounds depends on the part or by-product employed. For example, as a food supplement, amaranth oil (rich in squalene) can exert cardiovascular properties, while amaranth extract (rich in nitrites) can increase nitric oxide production (therefore improving endurance performance). On the other hand, as a functional ingredient, its gluten-free flours (containing fibre) can act as probiotics, whereas its proteins (with a peculiar amino acid profile) support muscle recovery. The few clinical results with athletic population suggest it can contribute to improved aerobic metabolism, but there is insufficient clinical data to draw any conclusion. Further research warrants elucidation of amaranth phytochemicals as promising ergogenic aids in sports by high-quality human clinical trials with both standardised products and ingredients in athletic population

Understanding of Mendelian Inheritance Model after conventional teaching methods in Secondary Education students

Mostrar que una nueva propuesta de enseñanza produce mejores actitudes y aprendizajes en los alumnos requiere disponer de un análisis de lo que se hace y se consigue con la enseñanza habitual. Para realizar dicho análisis se ha efectuado un estudio histórico y epistemológico de la evolución de las ideas en genética clásica, identificando los problemas que están en su origen, las ideas que permitieron avanzar y los obstáculos que hubo que superar. Como resultado de dicho estudio se han seleccionado un conjunto de indicadores de aprendizaje que deberían manifestarse en aquellas personas que hubieran comprendido los aspectos esenciales del modelo de herencia mendeliana, que se imparte en 4º de ESO. Dichos indicadores se han utilizado para analizar el aprendizaje tras la enseñanza convencional del tema. En este trabajo se presentan los resultados obtenidos que muestran las deficiencias más comunes y justifican la necesidad de una propuesta diferente.Showing that a new approach produces better learning and attitudes in students requires to have an analysis of what is done and what is achieved with conventional teaching. In order to perform such analysis, a historical and epistemological study of the evolution of ideas in classical genetics has been made, identifying problems at their source, the ideas that allowed progress and the obstacles that had to be overcome. As a result of this study, we selected a set of indicators of learning that should manifest themselves in those people who have understood the essential aspects of Mendelian inheritance model, which is taught in 4th of E.S.O. These indicators have been used to analyze the learning after conventional teaching of the subject. In this paper we present the results that show the most common deficiencies and justify the need for a different approach

Predictive model to improve the competence perception and academic performance in colleges

[ES] El objetivo de este trabajo fue analizar la relación del cuidado del docente, las necesidades psicológicas básicas (percepción de competencia, autonomía y relación con los demás) y la motivación académica sobre la percepción de competencia académica y de la nota media de los estudiantes. La muestra estuvo compuesta por 431 estudiantes universitarios (202 hombres y 220 mujeres) de una Universidad española, con una edad media de 22 años (DT = 2.41). Los instrumentos que se utilizaron fueron: La Escala del Cuidado del Profesor, la Escala de Satisfacción de las Necesidades Psicológicas en Educación, La Escala de Motivación Académica, y el Cuestionario de Percepción de Competencia Académica. Se calcularon los estadísticos descriptivos de todas las variables (medias y desviaciones típicas), la consistencia interna de cada factor, las correlaciones bivariadas de todas las variables, así como también se realizó un análisis de regresión estructural para testar el modelo. Los resultados obtenido[EN] The  aim  of  this  study  was  to  analyze the  relationship  of  teacher  care,  basic psychological   needs   (competence, autonomy and relationships with others perceive)  and  academic  motivation  on perceived  academic  competence  and the average grade of the students. The sample consisted of 431 college students (202 men and 220 women) Grade Physical and  Sport  Education  and  Psychology, belonging  to  the  University  Miguel Hernández of Elche, with a mean age of 22 years (SD = 2.41). The instruments used were: The Professor Scale of Care, The Satisfaction  Scale  of  Psychological  Needs, The    Education    Academic    Motivation Scale,  and  The  Questionnaire  Perceived Academic       Competence.   Descriptive statistics (means and standard deviations), the internal consistency of each factor, bivariate correlations for all variables, and a regression analysis to test the structural model were calculated. The results show a significant positive correlation between all tMoreno Murcia, JA.; Silveira Torregrosa, Y.; Alias García, A. (2015). Modelo predictivo para la mejora de la percepción de competencia y rendimiento académico en estudiantes universitarios. REDU. Revista de Docencia Universitaria. 13(2):173-188. https://doi.org/10.4995/redu.2015.5443OJS173188132Allen, J. P., Hauser, S., Eickholt, C., Bell, K., y O'Connor, T. (1994). Autonomy and relatedness in family interactions as predictors of expressions of negative adolescent affect. Journal of Research on Adolescence,4, 535-552.Allen, J. P., Pianta, R. C., Gregory, A., Mikami, A. Y., y Lun, J. (2011). An interaction-based approach to enhancing secondary school instruction and student achievement. Science, 333(6045), 1034-1037.Anderson, J. C., y Gerbin, D. W. (1988). Structural equation modelling in practice: a review and recommended two-step approach. Psychological Bulletin, 103, 411-423.Assor, A., Kaplan, H., y Roth, G. (2002). Choice is good, but relevance is excellent: Autonomy-enhancing and suppressing teacher behaviours in predicting student ́s engagement in school work. British Journal of Educational Psychology, 72, 261-278.Bagozzi, R. P., y Heatherton, T. F. (1994). A general approach to representing multifaceted personality constructs: Application to state self-esteem. Structural Equation Modeling, 1(1), 35-67.Bentler, P. M. (1989). EQS structural equations program manual. Los Angeles: BMDP Statistical Software.Bentler, P. M. (1980). Multivariate analysis with latent variables: causal modeling. Annual Review of Psychology, 31, 419-456.Bieg, S., y Mittag, W. (2010). Selbstbestimmte Lernmotivation [Self-determined motivation]. En T. Hascher y B. Schmitz (Eds.), Handbuch Pädagogische Interventionsforschung (pp. 188-198). Weinheim: Juventa.Black, A. E., y Deci, E. L. (2000). The effects of instructors' autonomy support and students' autonomous motivation on learning organic chemistry: A self-determination theory perspective. Science Education, 84, 740-756.Buendia, L. y Olmedo, E. (2003). Estudio transcultural de los enfoques de aprendizaje en educación superior. Revista de Investigación Educativa, 21(2), 371-386Byrne, B. M. (1994). Structural Equation Modeling With EQS and EQS/Windows. Newbury Park: Sage.Chantal, Y., Robin, P., Vernat, J. P., y Bernache-Asollant, I. (2005). Motivation, sportspersonship, and athletic aggression: a mediational analysis. Psychology of Sport and Exercise, 6, 233-249.Cheong, F. (2008). Using a Problem-Based Learning Approach to Teach an Intelligent Systems Course. Journal of Information Technology Education, 7, 47-60.Cokley, K. O., Bernard, N., Cunningham, D., y Motoike, J. (2001). A psychometric investigation of the Academic Motivation Scale using a United States sample. Measurement and Evaluation in Counseling and Development, 34, 109-119.Covington, M. V. (2000). Goal, theory, motivation and school achievement: an integrative review. Annual review of psychology, 51, 171-200.Deci, E. L. (1975). Intrinsic motivation. New York: Plenum.Deci, E. L., y Ryan, R. M. (1991). A motivational approach to self: Integration in personality. En R. Dienstbier (Ed.), Nebraska Symposium on Motivation: Vol. 38.Perspectives on motivation (pp. 237-288). Lincoln: University of Nebraska Press.Deci, E. L., y Ryan, R. M. (2000). The "what" and "why" of goal pursuits: Human needs and the self-determination of behaviour. Psychological Inquiry, 11, 227-268.Deci, E. L., y Ryan, R. M. (2002). Self-determination research: Reflections and future directions. En E. L. Deci y R. M. Ryan (Eds.),Handbook of self-determination research(pp. 431-441). Rochester, NY: University of Rochester Press.Dina, F. y Efklides, A. (2009). Student profiles of achievement goals, goal instructions and external feedback: Their effect on mathematical task performance and affect. European Journal of Education and Psychology, 2, 235-262.Furrer, C., y Skinner, E. (2003). Sense of relatedness as a factor in children's academic enagagement and performance. Journal of Educational Psychology, 95, 148-162.Gargallo, B., Garfella, P. R., Sanchez i Peris, F., Ros, C., y Serra, B. (2009): La influencia del auto concepto en el rendimiento académico en estudiantes universitarios.Revista de Orientación y Psicopedagogía, 20, 16-28.Gargallo, B., Sánchez, F., Ros, C., y Ferreras, A. (2010). Estilos docentes de los profesores universitarios. La percepción de los alumnos de los buenos profesores. Revista Iberoamericana de Educación, 51(4).Gillet, N., Rosnet, E., y Vallerand, R. J. (2008). Développement d'une échelle de satisfaction des besoins fondamentaux encontext sportif. Canadian Journal of Behavioural Science, 40(4), 230-237.González, D., y Díaz, Y. (2007). La importancia de promover en el aula estrategias de aprendizaje para elevar el nivel académico en los estudiantes de Psicología. Revista Iberoamericana de Educación, 40(1).Hernández, F., Arán, A., y Salmerón, H. (2012). Enfoques de aprendizaje y metodologías de enseñanza en la universidad. Revista Iberoamericana de Educación 60(3).Hernández, P. F., Rosario, P., y Cuesta Sáez de Tejada, J. D. (2010). Impacto de un programa de autorregulación del aprendizaje en estudiantes de Grado. Revista de Educación, 353, 571-588.Hernández Pina, F., Rosário, P., Cuesta Sáez de Tejada, J. D. Martínez Clares, P., y Ruiz Lara, E. (2006). Promoción del aprendizaje estratégico y competencias de aprendizaje en estudiantes de primero de universidad. Revista de Investigación Educativa, 24(2), 615-632.Hershberger, S. L. (2006). The problem of equivalent structural models. En G. R. Hancock, y R. O. Mueller (Eds.), Structutral equation modeling: a second course (pp. 13-42). Greenwich, CT: Information Age Publishing.Hughes, J. N., Wu, Jerry, Kwok, O., Villarreal, V., y Johnson, A. Y. (2012). Indirect effects of child reports of teacher-student relationship on achievement. Journal of Educational Psychology, 104, 350-365Klem, A. M., y Connell, J. P. (2004). Relationships matter: Linking teacher support to student engagement and achievement. Journal of School Health, 74(7), 262-273.Kowal, J., y Fortier, M. S. (2000). Testing relationships from the hierarchical model of intrinsic and extrinsic motivation using flow as a motivational consequence. Research Quarterly for Exercise and Sport, 71, 171-181Kunter, M. (2005). Multiple Zieleim Mathematikunterricht [Multiple goals in mathematicseducation]. Münster: Waxmann.León, J., Domínguez, E., Pérez, A., Núñez, J. L., y Martin-Albo, J. (2011). Traducción y validación de la versión española de la Échelle de Satisfaction des Besoins Psychologiques en el contexto educativo. Anales de Psicología, 28(2), 405-411.Losier, G. F., Vallerand, R. J., y Blais, M. R. (1993). Construction et validation de l'Échelle des Perceptions de Compétencedans les Domaines de Vie (EPCDV). Science et Comportement, 23, 1-16.Maccallum, R., y Austin, J. (2000). Applications of Structural Equation Modeling in Psychological Research. Annual Review of Psychology, 51, 201-226.Marsh, H. W., Richard, G. E., Johnson, S., Roche, l., y Tremayne, P. (1994). Physical Selfdecription Questionnaire: Psychometric Properties and a Nultitrait-multimethod Analysis of Relations to Existing Instruments. Journal of Sport and Exercise Psychology, 16, 270-305.Moreno-Murcia, J. A., Ruiz, Q. M. y Silveira, Y. (en prensa). Estimación del estudiante profundo a través de un modelo cognitivo-social. Revista Cultura y Educación.Moreno-Murcia, J. A., Ruiz, Q. M. y Silveira, Y. (en prensa). Perfiles motivacionales académicos en estudiantes adolescentes. Revista Cultura y EducaciónNúñez, J. L., Martín-Albo, J., y Navarro, J. G. (2005). Validación de la versión española de la Échelle de Motivation en Éducation. Psicothema, 17(2), 344-349.Pekrun, R. (2009). Emotions at school. En K. Wentzel y A. Wigfield (Eds.), Handbook of motivation at school (pp. 575-604). London: Routledge.Rakoczy, K., Klieme, E., y Pauli, C. (2008). Die Bedeutung der wahrgenommenen Unterstützung motivationsrelevanter Bedürfnisse und des Alltagsbezugs im Mathematikunterricht für die selbstbestimmte Motivation [The impact of the perceived support of basic psychological needs and of the perceived relevance of contents on students' self-determined motivation in mathematics instruction]. Zeitschriftfür Pädagogische Psychologie, 22, 25-35.Reeve, J., y Jang, H. (2006). What teachers say and do to support students' autonomy during a learning activity. Journal of Educational Psychology, 98, 209-218.Reeve, J., Jang, H., Carrell, D., Barch, J., y Jeon, S. (2004). Enhancing high school students' engagement by increasing their teachers autonomy support. Motivation and Emotion 28,147-69.Reeve, J. (2006). Teachers as facilitators: What autonomy-supportive teachers do and why their students benefit. The Elementary School Journal, 106, 225-236.Reis, H. T, Sheldon, K. M., Gable, S. L., Roscoe, J., y Ryan, R. M. (2000). Daily well-being: The role of autonomy, competence, and relatedness. Personality and Social Psychology Bulletin, 26, 419-435.Röder, B., y Kleine, D. (2007). Selbstbestimmung/Autonomie. En M. Jerusalem, S. Drössler, D. Kleine, J. Klein-HeBling, W. Mittag, y B. Röder (Eds.), Förderung von Selbstwirksamkeitund Selbstbestimmungim Unterricht. Berlin: Humboldt-Universitätzu Berlin.Roth, G., Assor, A., Kanat-Maymon, Y., y Kaplan, H. (2007). Autonomous motivation for teaching: How self-determined teaching may lead to self-determined learning. Journal of Educational Psychology, 99, 761-774.Ryan, R. y Deci, E. (2009). Promoting self-determined school engagement: Motivation, learning, and well-being. En K. Wentzel y A. Wigfield (Eds.), Handbook of motivation at school (pp. 171-195). New York: Routledge.Sakiz, G., Pape, S., J., y Hoy, A., W. (2012). Does perceived teacher affective support matter for middle school students in mathematics classrooms? Journal of School Psychology, 50(2), 235-255Sheldon, K. M., Elliot, A. J., Kim, Y., y Kasser, T. (2001). What's satisfying about satisfying events? Comparing ten candidate psychological needs. Journal of Personality and Social Psychology, 80, 325-339.Sheldon, K. M., Ryan, R. M., y Reis, H. R. (1996). What makes for a good day? Competence and autonomy in the day and in the person. Personality and Social Psychology Bulletin, 22, 1270-1279.Vansteenkiste, Lens, W., y Deci, E. L. (2006). Intrinsic Versus Extrinsic Goal Contents in Self-Determination Theory: Another Look at the Quality of Academic Motivation. Educational Psychologist, 41(1), 19-31.Vansteenkiste, M., Zhou, M., Lens, W., y Soenens, J. B. (2005). Experiences of autonomy and control among Chinese learners: Vitalizing or inmobilizing? Journal of Educational Psychology, 97, 468-483.Vallerand, R. J., Blais, M. R., Brière, N. M., y Pelletier, L. G (1989). Construction et validation de l ́Échelle de Motivation en Éducation (EME).Canadian Journal of Behavioral Sciences, 21, 323-349.Vallerand, R. J. (2007). Intrinsic and extrinsic motivation in sport and physical activity. En G. Tenenbaum y R. C. Eklund (Eds.), Handbook of sport Psychology (3ª ed., pp. 59-83). New York: Wile

Sensitivity of combustion noise and NOx and soot emissions to pilot injection in PCCI Diesel engines

Diesel engines are the most commonly used internal combustion engines nowadays, especially in European transportation. This preference is due to their low consumption and acceptable driveability and comfort. However, the main disadvantages of traditional direct injection Diesel engines are their high levels of noise, nitrogen oxides (NO x) and soot emissions, and the usage of fossil fuels. In order to tackle the problem of high emission levels, new combustion concepts have been recently developed. A good example is the premixed charge compression ignition (PCCI) combustion, a strategy in which early injections are used, causing a burning process in which more fuel is burned in premixed conditions, which affects combustion noise. The use of a pilot injection has become an effective tool for reducing combustion noise. The main objective of this paper is to analyze experimentally the pollutant emissions, combustion noise, and performance of a Diesel engine operating under PCCI combustion with the use of a pilot injection. In addition, a novel methodology, based on the decomposition of the in-cylinder pressure signal, was used for combustion noise analysis. The results show that while the PCCI combustion has potential to reduce significantly the NO x and soot emission levels, compared to conventional Diesel combustion strategy, combustion noise continues to be a critical issue for the implementation of this new combustion concept in passenger cars.This work has been partially supported by Ministerio de Educacin y Ciencia through Grant No. TRA2006-13782. L.F. Monico holds the Grant 2009/003 from Santiago Grisolia Program of Generalitat Valenciana.Torregrosa, AJ.; Broatch Jacobi, JA.; García Martínez, A.; Mónico Muñoz, LF. (2013). Sensitivity of combustion noise and NOx and soot emissions to pilot injection in PCCI Diesel engines. Applied Energy. 104:149-157. https://doi.org/10.1016/j.apenergy.2012.11.040S14915710

Pomegranate Extract Improves Maximal Performance of Trained Cyclists after an Exhausting Endurance Trial: A Randomised Controlled Trial

The efficacy of pomegranate (Punica granatum) extract (PE) for improving performance and post-exercise recovery in an active population was equivocal in previous studies. In this study, a randomised, double-blinded, placebo-controlled, balanced, cross-over trial with two arms was conducted. Eligibility criteria for participants were as follows: male, amateur cyclist, with a training routine of 2 to 4 sessions per week (at least one hour per session). The cyclists (n = 26) were divided into treatment (PE) and placebo (PLA) groups for a period of 15 days. After physical tests, the groups were exchanged after a 14-day washout period. Exercise tests consisted of endurance bouts (square-wave endurance exercise test followed by an incremental exercise test to exhaustion) and an eccentric exercise drill. The objective was to assess the efficacy of PE in performance outcomes and post-exercise muscular recovery and force restoration after a prolonged submaximal effort. Twenty-six participants were included for statistical analysis. There was a statistically significant difference in total time to exhaustion (TTE)(17.66–170.94 s, p < 0.02) and the time to reach ventilatory threshold 2 (VT2)(26.98–82.55 s, p < 0.001), with greater values for the PE compared to the PLA group. No significant results were obtained for force restoration in the isokinetic unilateral low limb test. PE, after a prolonged submaximal effort, may be effective in improving performance outcomes at maximal effort and might help to restore force in the damaged muscles.Actividad Física y Deport

Estimates of deep learning student across of a social cognitive model

El objetivo de este estudio consistió en comprobar el poder de predicción del soporte de autonomía, las necesidades psicológicas básicas (percepción de competencia, de autonomía y de relación con los demás) y la motivación autodeterminada sobre el estudiante adolescente con un enfoque de aprendizaje profundo. La muestra ha estado compuesta por 405 estudiantes españoles de Educación Secundaria Obligatoria, Bachillerato y Ciclos Formativos (212 mujeres y 193 hombres), con edades comprendidas entre los 12 y 20 años (M = 16.4, DT = 2.45). Se administraron las escalas Student’s Percepcion of Autonomy Support, Teacher’s Care, la Échelle de Satisfacción des Besoins Psychologiques, Academic Motivation Scale, High School Version y Revised Two Factor Study Process Questionnaire. Se adaptaron y validaron las escalas Student’s Percepcion of Autonomy Support y Teacher’s Care al contexto español. Se calcularon los estadísticos descriptivos de todas las variables objeto de estudio (medias y desviaciones típicas), se analizó la consistencia interna de cada factor mediante el coeficiente de alfa de Cronbach y se realizaron correlaciones bivariadas. Para comprobar la relación predictiva existente entre las variables propuestas se analizaron los modelos de medida del modelo de regresión estructural. Los resultados mostraron que el soporte de autonomía docente predijo positivamente a las necesidades psicológicas básicas, estas a la motivación autodeterminada y ésta finalmente predijo positivamente el enfoque de aprendizaje profundo del estudiante. Se concluye que el apoyo a la autonomía al estudiante por parte del docente puede ser un elemento clave para lograr motivar al estudiante hacia un aprendizaje autónomo y permanente.The aim of this paper is to examine the relationship between autonomy support, basic psychological needs (perception of competence, autonomy and relatedness) and self-determined motivation on student adolescents to whom a deep approach to learning was applied. The sample consisted of 405 Spanish students of Compulsory Secondary Education, High School and Vocational Training (212 women and 193 men), aged between 12 and 20 (M = 16.4, DT = 2.45). The instruments used were: Student’s, Perception of Autonomy Support, Teacher’s Care, L’Échelle de Satisfaction des Besoins Psychologiques, Academic Motivation Scale, as well as the High School Version and the Revised Two Factor Study Process Questionnaire. The scales of Perception of Autonomy Support and Teacher’s Care was translated into Spanish context and validated. It was carried out descriptive statistics (means and standard deviations), the internal consistency of each factor with the Cronbach’s alpha coefficient, and bivariate correlations for all variables. In order to examine the predictive relationship between all proposed variables, analysis of models used to measure the structural relationship model was performed. It was found that the autonomy support applied by teachers led to a satisfactory prediction of psychological mediators, which in turn allowed for predicting the selfdetermined motivation in each student’s deep-learning approach. It was concluded that a teacher, by supporting autonomy, can considerably motivate students so that they learn on an autonomous and permanent basis.Universidad de Granada. Departamento de Didáctica y Organización Escolar. Grupo FORCE (HUM386

Medios de comunicación, representaciones y percepciones. El caso de la mujer política.

Este trabajo trata de comparar, por un lado, la representación de la mujer en los medios de comunicación y, por otro, su percepción por parte de la sociedad. En concreto, se analiza, por su relevancia social y mediática, la mujer política, a través de dos métodos de trabajo: un análisis de contenido sobre las noticias de diversos medios de comunicación y una encuesta que tiene como objetivo detectar los discursos sociales referidos a la mujer en el contexto político. Por último, se establece una comparación entre los resultados de ambos aspectos.This study seeks to compare the one hand, women’s representation in the media and, secondly, their perception by society. In particular, it examines, for its social and mediatic relevance, the case of the politic woman, through two working methods: a content analysis of various media and a poll that aims to detect speeches relating to social women in the political context. Finally, it provides a comparison between the results of both aspects

Numerical solution of turbulence problems by solving Burgers' equation

In this work we generate the numerical solutions of Burgers' equation by applying the Crank-Nicholson method and different schemes for solving nonlinear systems, instead of using Hopf-Cole transformation to reduce Burgers' equation into the linear heat equation. The method is analyzed on two test problems in order to check its efficiency on different kinds of initial conditions. Numerical solutions as well as exact solutions for different values of viscosity are calculated, concluding that the numerical results are very close to the exact solution.Cordero Barbero, A.; Franqués García, AM.; Torregrosa Sánchez, JR. (2015). Numerical solution of turbulence problems by solving Burgers' equation. Algorithms. 8(2):224-233. doi:10.3390/a8020224S22423382Lowrie, R. B. (2004). A comparison of implicit time integration methods for nonlinear relaxation and diffusion. Journal of Computational Physics, 196(2), 566-590. doi:10.1016/j.jcp.2003.11.016An, H.-B., Mo, Z.-Y., Xu, X.-W., & Liu, X. (2009). On choosing a nonlinear initial iterate for solving the 2-D 3-T heat conduction equations. Journal of Computational Physics, 228(9), 3268-3287. doi:10.1016/j.jcp.2009.01.024Bruns, D. D., & Bailey, J. E. (1977). Nonlinear feedback control for operating a nonisothermal CSTR near an unstable steady state. Chemical Engineering Science, 32(3), 257-264. doi:10.1016/0009-2509(77)80203-0Willert, J., Park, H., & Knoll, D. A. (2014). A comparison of acceleration methods for solving the neutron transport k -eigenvalue problem. Journal of Computational Physics, 274, 681-694. doi:10.1016/j.jcp.2014.06.044Andreu, C., Cambil, N., Cordero, A., & Torregrosa, J. R. (2013). Preliminary Orbit Determination of Artificial Satellites: A Vectorial Sixth-Order Approach. Abstract and Applied Analysis, 2013, 1-10. doi:10.1155/2013/960582Kadalbajoo, M. K., & Awasthi, A. (2006). A numerical method based on Crank-Nicolson scheme for Burgers’ equation. Applied Mathematics and Computation, 182(2), 1430-1442. doi:10.1016/j.amc.2006.05.030Hassanien, I. A., Salama, A. A., & Hosham, H. A. (2005). Fourth-order finite difference method for solving Burgers’ equation. Applied Mathematics and Computation, 170(2), 781-800. doi:10.1016/j.amc.2004.12.052Wani, S. S., & Thakar, S. H. (2013). Crank-Nicolson Type Method for Burgers Equation. International Journal of Applied Physics and Mathematics, 324-328. doi:10.7763/ijapm.2013.v3.230Arroyo, V., Cordero, A., & Torregrosa, J. R. (2011). Approximation of artificial satellites’ preliminary orbits: The efficiency challenge. Mathematical and Computer Modelling, 54(7-8), 1802-1807. doi:10.1016/j.mcm.2010.11.063Mittal, R. C., & Singhal, P. (1993). Numerical solution of Burger’s equation. Communications in Numerical Methods in Engineering, 9(5), 397-406. doi:10.1002/cnm.164009050

Development of non-reflecting boundary condition for application in 3D computational fluid dynamics codes

This is an Author's Accepted Manuscript of an article published in [include the complete citation information for the final version of the article as published in the Engineering applications of computational fluid mechanics, 2012 © Taylor & Francis, available online at: http://doi.org/ 10.1080/19942060.2012.11015434[EN] Numerical computations are commonly used for better understanding the unsteady processes in internal combustion engine components and their acoustic behavior. The acoustic characterization of a system requires that reflections from duct terminations are avoided, which is achieved either by using highly dissipative terminations or, when an impulsive excitation is used, by placing long ducts between the system under study and the duct ends. In the latter case, the simulation of such a procedure would require a large computational domain with the associated high computational cost, unless non-reflecting boundary conditions are used. In this paper, first the different non-reflecting boundary conditions available in ANSYS-FLUENT are evaluated. Then, the development and implementation of an anechoic termination in a 3D-CFD code is presented. The performance of the new implementation is first validated in the classic Sod's shock tube problem, and then checked against numerical and experimental results of the flow and acoustic fields in automotive exhaust mufflers. The results obtained compare favorably with those from the conventional CFD approach and experiments, while the computational cost is significantly reduced.This work has been partially supported by Ministerio de Ciencia e Innovacion through grant No. DPI2009-14290. The authors wish to thank Dr. David R. Perry for his kind assistance in manuscript editing.Torregrosa, AJ.; Fajardo, P.; Gil Megías, A.; Navarro García, R. (2012). Development of non-reflecting boundary condition for application in 3D computational fluid dynamics codes. Engineering Applications of Computational Fluid Mechanics. 6(3):447-460. https://doi.org/10.1080/19942060.2012.11015434S44746063ANSYS Inc. (2009). Ansys Fluent 12.0 User’s Guide. Canonsburg, PA: ANSYS Inc.Benson RS (1982).The Thermodynamics and Gas Dynamics of Internal Combustion Engines. Volume 1, Oxford: Oxford University Press.Luján JM, Bermúdez V, Serrano JR, Cervelló C (2002). Test bench for turbocharger groups characterization.SAE Paper2002–01-0163.Munjal ML (1987).Acoustics of Ducts and Mufflers. New York: Willey.Onorati A, Montenegro G, D’Errico G (2006). Prediction of the attenuation characteristics of IC engine silencers by 1-D and multi-D simulation models.SAE Paper2006–01-1541.Patil AR, Sajanpawar PR, Masurekar VV (1996) Acoustic three dimensional finite element analysis of a muffler.SAE Paper960189

Design, construction and testing of an apricot tractor-trailed harvester

[ENG]The purpose of this research is to facilitate the mechanical harvesting of apricots (Prunus armeniaca L.) for industry. A tractor-trailed harvester was built to catch the fruits detached from apricot (cv. Búlida) trees by vibratory systems. This machine is a low profile catcher that can move under the trees in high-density canopies where umbrella-type harvesters cannot. The trailer is able to work under trees with as little free-trunk height as 0.35 m. The tests were done in 5- to 9-year-old apricot trees, planted in two frame, 2.5 m and 4.5 m in-the-row distances, with 6.5 m between rows in both cases. To detach the fruit, two hand-held pneumatic shakers were used. Harvest rate was 61 and 44 trees h-1 for each type of orchard, respectively. The main conclusion is that the trailer, together with branch-shakers, can work in narrow orchards of low canopy trees where other machines can not go in. [ESP] El objetivo de este trabajo fue facilitar la recolección mecanizada de albaricoques (Prunus armeniaca L.) para industria. Se ha construido un remolque recolector arrastrado por tractor para recoger los albaricoques cv. Búlida derribados de los árboles mediante sistemas vibratorios. El remolque puede trabajar a muy poca altura sobre el nivel del suelo, con lo que puede moverse bajo los árboles en plantaciones de alta densidad, en las que las cosechadoras basadas en paraguas invertidos no pueden actuar. Además, el remolque se puede adaptar a árboles con alturas de tronco tan reducidas como 0,35 m. Los ensayos se llevaron a cabo en albaricoqueros de 5 a 9 años de edad y plantados en marcos de 2,5 y 4,5 m entre árboles de la fila y 6,5 m entre filas. El derribo de los frutos se realizó con vibradores neumáticos. La capacidad de trabajo del equipo fue de 61 y 44 árboles h-1 para cada distancia de plantación, respectivamente. La principal conclusión es que el remolque, conjuntamente con vibradores de ramas, puede trabajar en plantaciones de marco estrecho y árboles con la cruz del tronco baja donde otras máquinas no pueden actuar.The authors would like to thank the Spanish Ministerio de Ciencia y Tecnología for supporting the AGL2001-3075 project, the Region of Murcia’s Consejería de Agricultura, Agua y Medio Ambiente for support through the Séneca AGR/2/FS/01D project