Robust Generic Model Control For Dissolved Oxygen In Activated Sludge Wastewater Plant

The main issue of this paper is the design of a class of SISO robust control law for the regulation of dissolved oxygen (DO) of an industrial Activated Sludge Wastewater Plant via the air flow rate (non-affine control input). The control design is related with an uncertainty estimator (reduced order observer) based Generic Model Control (GMC). The desired dissolved oxygen trajectory is proposed as a Proportional-Integral (PI) form of the regulation error and the modeling error related with the respiration rate and the oxygen mass transfer coefficient are on-line estimated with a reduced order observer, these structures produce a feedback/feed forward regulator which is robust against model uncertainties and disturbances. The system’s closed-loop behavior is analyzed via the estimation error and regulation error dynamics. The performance of the proposed control law is illustrated with numerical simulations, comparing the proposed controller with a well-tuned PI controller

On-line estimation of VFA concentration in anaerobic digestion via methane outflow rate measurements

"This paper deals with the design of a robust nonlinear observer as a software sensor to achieve the on-line estimation of the concentration of Volatile Fatty Acids (VFA) in a class of continuous anaerobic digesters (AD). Taking into account the limited availability of on-line sensors for AD process, in this contribution is assumed that only the methane outflow rate is available for on-line measurement. The estimation method is based on a modified version for a two-dimensional mathematical model of AD process. From the differential algebraic observability approach it is shown that the VFA concentration is detectable from the methane outflow rate measurements. The observer convergence is analyzed by using Lyapunov stability techniques. Numerical simulations illustrate the effectiveness of the proposed estimation method for a four-dimensional AD model with uncertainties associated with unmodeled dynamics and disturbances in the inflow composition.

拉古纳大学本科学生学业投入及其对学习成果的影响

The attitude and involvement with which undergraduate university students approach their training process can have a significant impact on the academic results they obtain. The relationship that can occur between low involvement and the possibility of failing or dropping out of studies has led us to propose this research, where the relationship between engagement and academic performance is deepened. The engagement refers to the feeling of well-being of the students with respect to a challenge related to their training process. Students who are studying at university are exposed to living situations that make them more or less committed to their learning process, which can lead to obtain better or worse academic results. This ex-post-facto quantitative study, which was carried out with a sample of 564 first and second year students from the three degrees of the Faculty of Education of the University of La Laguna (Spain), aimed to analyze the relationship between academic commitment and performance in studies. The results reveal that students with higher scores in the different structural dimensions of academic commitment (vigor, dedication and absorption) have higher grades in the subjects they take. The discussion of the study focuses on the need to plan strategies to promote academic commitment in order to strengthen both the trajectories of adaptation and permanence in the degree and the achievement of better academic results in university students.La actitud y la implicación con la que los estudiantes universitarios de grado afrontan su proceso formativo puede incidir de manera significativa en los resultados académicos que obtengan.  La relación que puede darse entre una baja implicación y la posibilidad de fracasar o abandonar los estudios ha llevado a plantear esta investigación, donde se profundiza en la relación entre el engagement y el rendimiento académico. El engagement hace referencia a la sensación de bienestar del alumnado respecto a un desafío relacionado con su proceso formativo. El alumnado que cursa estudios universitarios está expuesto a vivir situaciones que les hacen estar más o menos comprometidos con su proceso de aprendizaje, pudiéndoles llevar a obtener mejores o peores resultados académicos. Este estudio de corte cuantitativo ex-post-facto, que se llevó a cabo con una muestra de 564 estudiantes de primer y segundo curso de los tres grados de la Facultad de Educación de la Universidad de La Laguna (España), tiene como objetivo analizar la relación entre el engagement académico y el rendimiento en los estudios. Los resultados revelan que el alumnado con mayores puntuaciones en las distintas dimensiones estructurales del engagement académico (vigor, dedicación y absorción) presenta mayores calificaciones en las asignaturas que cursa. La discusión del estudio se centra en la necesidad de planificar estrategias promotoras del engagement académico para fortalecer tanto las trayectorias de adaptación y permanencia en la titulación como la obtención de mejores resultados académicos en el alumnado universitario.A atitude e o envolvimento com que os estudantes universitários de licenciatura enfrentam o seu processo de formação pode ter um impacto significativo nos resultados académicos que obtêm.  A relação que pode existir entre o baixo envolvimento e a possibilidade de insucesso ou de abandono justificou esta investigação, na qual se explora a relação entre o engagement e o desempenho académico. O engagement refere-se ao sentimento de bem-estar dos estudantes em relação a um desafio relacionado com o seu processo formativo. Os estudantes que frequentam um curso de ensino superior são expostos a situações que os tornam mais ou menos empenhados no seu processo de aprendizagem, o que os pode levar a obter melhores ou piores resultados académicos. Este estudo quantitativo ex post facto, que foi realizado com uma amostra de 564 estudantes do primeiro e segundo anos dos três cursos de licenciatura da Faculdade de Educação da Universidade de La Laguna (Espanha), tem como objetivo analisar a relação entre o engagement académico e o desempenho no curso. Os resultados revelam que os estudantes com notas mais elevadas nas diferentes dimensões estruturais do engagement académico (vigor, dedicação e absorção) têm notas mais elevadas nas disciplinas que frequentam. A discussão do estudo centra-se na necessidade de planear estratégias para promover o engagement académico, a fim de reforçar não só as trajetórias de adaptação e permanência no curso, como a obtenção de melhores resultados académicos dos estudantes universitários.A atitude e o envolvimento com que os estudantes universitários de licenciatura enfrentam o seu processo de formação pode ter um impacto significativo nos resultados académicos que obtêm.  A relação que pode existir entre o baixo envolvimento e a possibilidade de insucesso ou de abandono justificou esta investigação, na qual se explora a relação entre o engagement e o desempenho académico. O engagement refere-se ao sentimento de bem-estar dos estudantes em relação a um desafio relacionado com o seu processo formativo. Os estudantes que frequentam um curso de ensino superior são expostos a situações que os tornam mais ou menos empenhados no seu processo de aprendizagem, o que os pode levar a obter melhores ou piores resultados académicos. Este estudo quantitativo ex post facto, que foi realizado com uma amostra de 564 estudantes do primeiro e segundo anos dos três cursos de licenciatura da Faculdade de Educação da Universidade de La Laguna (Espanha), tem como objetivo analisar a relação entre o engagement académico e o desempenho no curso. Os resultados revelam que os estudantes com notas mais elevadas nas diferentes dimensões estruturais do engagement académico (vigor, dedicação e absorção) têm notas mais elevadas nas disciplinas que frequentam. A discussão do estudo centra-se na necessidade de planear estratégias para promover o engagement académico, a fim de reforçar não só as trajetórias de adaptação e permanência no curso, como a obtenção de melhores resultados académicos dos estudantes universitários.本科学生在求学过程中的态度及投入会对其学习成果产生较明显的影响。该研究的提出是基于对较低的学业投入与可能导致的学业失败及辍学间关系的考量。通过该研究深入探讨学生学业投入和学习成果间的关系。学业投入是指学生在求学过程中面对相关挑战时所获得的幸福感。大学生所处的环境强迫他们或多或少地致力于自己的学习过程，从而得到或优或差的学业成绩。研究采用事后回溯定量研究，以来自西班牙拉古纳大学教育系三个专业的564名大一大二学生为研究样本，旨在分析学生学业投入及学习成果间的关系。研究结果表明在学业投入结构的不同维度（活力、投入及专注）中获得高分的学生，研修的课程分数更高。该研究讨论的重点集中在探讨建立推动学业投入策略的必要性。有了这样的策略，不仅能加强学生在教育轨迹中的适应性和研读学位的持久性，还能鼓励学生取得更优秀的学业成绩

Nonlinear and robust control strategy based on chemotherapy to minimize the HIV concentration in blood plasma

"A nonlinear PI-type control strategy is designed in order to minimize the HIV concentration in blood plasma, via medical drug injection, under the framework of bounded uncertain input disturbances. For control design it is considered a simplified mathematical model of the virus infection as a benchmark. The model is based on mass balances of healthy cells, infected cells, and the virus concentrations. The proposed controller contains a nonlinear feedback PI structure of bounded functions of the regulation error. The closed-loop stability of the system is analyzed via Lyapunov technique, in which robustness against system disturbances is demonstrated. Numerical experiments show a satisfactory performance of the proposed methodology as a HIV therapy, in which the virion particles and the infected CD4+T cells are minimized and, as an interesting result, the drug dosage can be suspended, thus avoiding drug resistance from the virus. Finally, the proposed controller is compared to a standard sliding-mode and hyperbolic tangent controllers showing better performance.

Dynamic nonlinear feedback control applied to improve butanol production by Clostridium acetobutylicum

"The goal of this work is to present a closed-loop operational strategy in order to improve the butanol production in an anaerobic continuous bioreactor for the called Acetone-Butanol-Ethanol (ABE) process. The proposed control scheme considers a class of feedback signal which includes a nonlinear bounded function of the regulation error. The control scheme is applied to a phenomenological unstructured kinetic model obtained from an experimental and metabolic study of butanol production by Clostridium acetobutylicum, which allows the proposed structure to predict several operational conditions from batch and continuous regimes. Numerical experiments using the proposed model considering continuous operation were performed in order to find a feasible operating region for maximum butanol production at open-loop regime. The proposed methodology is applied to regulate the product concentration, manipulating the dilution rate to lead to a higher butanol productivity. The closed-loop behaviour of the bioreactor is analysed, finding that the proposed controller minimizes the response time of the system and allows it to achieve a productivity gain of 55 % over open-loop operation. Further numerical experiments show the satisfactory closed-loop performance of the proposed methodology in comparison with a PI controller.

A giant foraminifer that converges to the feeding strategy of carnivorous sponges: Spiculosiphon oceana sp. nov. (Foraminifera, Astrorhizida)

14 páginas, 6 figurasThe foraminifer Spiculosiphon oceana sp. nov. is a giant (>4 cm) agglutinated astrorhizid, which makes the second known species of this unusual genus and its first Mediterranean record. It has a peculiar stalked, capitate, monothalamous test. Bleach digestion and X-ray microanalysis indicated the test to be made exclusively of siliceous sponge spicules agglutinated in organic cement. The organism stands on a hollow, 4 cm long, 0.5 cm thick stalk built with highly selected, long and thin spicule fragments, tightly cemented together in parallel to the main axis of the stalk. The proximal end of the stalk is closed and slightly expanded into a bulb-like structure, designed to penetrate between the sand grains and maintaining the test upright while avoiding a permanent attachment to the substratum. The distal stalk end becomes a hollow, globelike structure that contains the main protoplasm. The globelike region is built with loosely agglutinated and irregularlyshaped spicules, allowing extrusion of the pseudopodia through the cavities between the spicules. The globelike structure also serves as an anchoring basis, from which long and thin, solid tracts protrude radially to make a spherical crown that attains about 4 mm in total diameter. The radiating tracts are built with highly selected aciculate spicule fragments held together with a translucent organic cement. They provide skeletal support for the extension of a crown of pseudopodia into the water column. This arrangement is thought to enhance the chances of the pseudopodia to contact demersal planktonic prey. In summary, Spiculosiphon species collect and arrange sponge spicules with high selectivity to recreate a body morphology that strongly converges to that of some carnivorous sponges, which allows these predatory foraminifera to exploit a prey capturing strategy similar to that of the carnivorous sponges. This idea is also consistent with our report of an additional, yet undetermined, Spiculosiphon species occurring in the same sublittoral Mediterranean cave where carnivorous sponges were first discovered.This research has benefited from funds of the Spanish Ministry of Economy and Competitiveness grant (CTM2012-37787) to MM.Peer reviewe

Generic competences and learning outcomes in the degree studies of Pedagogy

[EN] In this article, the training and learning outcomes in generic competences in the degree titles of university education are studied in depth. Learning outcomes are concretions of what a student is expected to know, understand and / or be able to do at the end of a learning period. Although there has been progress in the curricular designs for competences, much remains to be done to improve the systems of evaluation by competences, specifying well-defined learning outcomes and contextualized in the different subjects of the curriculum. To address this problem, a sample of teaching guides of the degree of Pedagogy of the University of La Laguna was analyzed to assess the treatment given to generic competences and learning outcomes. The study showed that not all the generic competences that appear in the certificates of verification of the title are developed, training activities are not contemplated, nor are learning outcomes specified for this type of competences. Based on the information collected, a practical guide was designed in which innovative proposals aimed at teachers were defined, in order to improve the development and evaluation of generic competences.[ES] En este artículo se profundiza en la formación y resultados de aprendizaje en competencias genéricas en los títulos de grado de la enseñanza universitaria. Los resultados de aprendizaje son concreciones de lo que se espera que un estudiante sepa, comprenda y/o sea capaz de hacer al final de un periodo de aprendizaje. Aunque se ha avanzado en los diseños curriculares por competencias, queda mucho por hacer para mejorar los sistemas de evaluación por competencias, concretando resultados de aprendizaje bien definidos y contextualizados en las distintas asignaturas del plan de estudios. Para abordar esta problemática, se analizó una muestra de guías docentes del grado de Pedagogía de la Universidad de La Laguna, con la finalidad de valorar el tratamiento que se le daba a las competencias genéricas y a los resultados de aprendizaje. El estudio puso de manifiesto que no se desarrollan todas las competencias genéricas que figuran en las memorias de verificación del título, no se contemplan actividades formativas, ni se concretan resultados de aprendizaje para este tipo de competencias. A partir de la información recogida, se diseñó una guía práctica en la que se concretaron propuestas innovadoras dirigidas al profesorado, con el fin de mejorar el desarrollo y evaluación de las competencias genéricas.Alvarez-Pérez, PR.; López-Aguilar, D. (2018). Competencias genéricas y resultados de aprendizaje en los estudios de grado de Pedagogía. 137-154. doi:10.4995/redu.2018.889513715

Psychometric properties of the Questionnaire On Self-Regulation Of The Learning Process (CAPA) in university degree students

Este artículo recoge el análisis de las propiedades psicométricas del Cuestionario sobre Autorregulación del proceso de Aprendizaje (CAPA) en una muestra de 504 estudiantes universitarios de grado de la Universidad de La Laguna (España). La autorregulación del aprendizaje constituye uno de los factores más consistentes de predicción de la adaptación y del rendimiento académico del alumnado, por lo que identificar qué estrategias emplean los estudiantes durante su proceso de aprendizaje, qué factores facilitan o dificultan su empleo y en qué medida todo ello influye en el desempeño académico, es un objetivo estratégico de la educación superior, donde se vienen detectando cifras elevadas de fracaso y abandono de los estudios. Por este motivo, el objetivo de esta investigación fue elaborar, validar y aplicar una prueba para evaluar la capacidad de autorregulación de los estudiantes universitarios de grado. Siguiendo un modelo de ecuaciones estructurales, se comprobó que la escala de medida diseñada era válida y confiable para medir el constructo de autorregulación del aprendizaje, lo que se demostró con una muestra de estudiantes universitarios de nuevo ingreso. Los resultados confirman la importancia de contar con un instrumento de medida adaptado a las características del alumnado universitario, con el fin de analizar las dificultades que tienen durante el proceso de estudio y orientarles en su aprendizaje para prevenir el fracaso académico.This article includes the analysis of the psychometric properties of the Questionnaire on Self- regulation of the Learning Process (CAPA) in a sample of 504 undergraduate university students from the University of La Laguna (Spain). Self-regulation of learning is one of the most consistent predictors of student adaptation and academic performance, so identifying which strategies students use during their learning process, which factors facilitate or hinder their use and to what extent all this influences academic performance, it is a strategic objective of higher education, where high rates of failure and abandonment of studies have been detected. For this reason, the objective of this research was to develop and validate a test to assess the self-regulation capacity of undergraduate university students. Following a model of structural equations, it was verified that the measurement scale designed was valid and reliable to measure the construct of self-regulation of learning, which was demonstrated with a sample of freshmen university students. The results confirm the importance of having a measurement instrument adapted to the characteristics of university students, in order to analyse the difficulties they have during the study process and guide them in their learning to prevent academic failure

La construcción de la identidad personal y profesional de los deportistas de alto nivel

La retirada de la práctica deportiva constituye una de las fases más complejas en la trayectoria vital de los deportistas de alto nivel, y requiere de una adecuada preparación y planificación previas. La definición del proyecto profesional y vital puede ayudar a los deportistas a afrontar este proceso antes, durante y después de la retirada de su actividad. En relación con esta problemática, el objetivo central del presente estudio fue analizar la influencia de distintos factores asociados al desarrollo profesional y vital de deportistas españoles de alto nivel. Para la recogida de datos se empleó una entrevista semiestructurada, que se organizó en torno a cinco dimensiones básicas: competición deportiva de alto nivel (I); fase exploratoria, conocimiento de sí mismo (II); fase exploratoria, conocimiento del entorno (III); fase de definición de las metas profesionales (IV), y fase de toma de decisiones vocacionales y profesionales (V). La muestra estuvo compuesta por un total de 16 deportistas de alto nivel acreditados por el Consejo Superior de Deportes. A partir de los resultados obtenidos, cabe destacar que los participantes en el estudio eran conscientes de la importancia que tenía la formación académica y el diseño de un proyecto personal y de vida sobre su futuro desarrollo profesional.La retirada de la pràctica esportiva constitueix una de les fases més complexes en la trajectòria vital dels esportistes d'alt nivell, y requereix una adequada preparació i planificació prèvies. La definició del projecte professional i vital pot ajudar els esportistes a afrontar aquest procés abans, durant i després de la retirada de la seva activitat. En relació amb aquesta problemàtica, l'objectiu central del present estudi va ser analitzar la influència de diferents factors associats al desenvolupament professional i vital d'esportistes espanyols d'alt nivell. Per fer la recollida de dades es va emprar una entrevista semiestructurada, que es va organitzar entorn a cinc dimensions bàsiques: competició esportiva d'alt nivell (I); fase exploratòria, coneixement de si mateix (II); fase exploratòria, coneixement de l'entorn (III); fase de definició de les metes professionals (IV), i fase de presa de decisions vocacionals i professionals (V). La mostra va estar composta per un total de 16 esportistes d'alt nivell acreditats pel Consell Superior d'Esports. A partir dels resultats obtinguts, cal destacar que els participants en l'estudi eren conscients de la importància que tenia la formació acadèmica i el disseny d'un projecte personal i de vida sobre el seu futur desenvolupament professional.Withdrawal from sport is one of the most complex stages in the life trajectories of high-level athletes and requires appropriate preparation and planning. Defining a professional and life project can help athletes cope with this process before, during, and after withdrawing from sport. In this regard, the main aim of this study was to analyze the influence of different factors associated with the professional and personal development of high-level Spanish athletes. Data were collected by means of a semi-structured interview organized into five basic dimensions: (I) sports competition; (II) exploratory phase and self-knowledge; (III) exploratory phase and knowledge of the environment; (IV) defining career goals; and (V) vocational and professional decisions. The sample comprised a total of 16 high-level athletes accredited by the Higher Sports Council of Spain. The results show that the athletes were aware of the importance of academic training and designing a personal life project for their future professional development