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[EN] This manuscript presents a general overview of the microalgae production process from a modelling and control perspective. First, the main advantages and the potential of these microorganisms are motivated, describing the dierent type of reactors used for their cultivation. Afterwards, the process dynamics, which is very complex and variable due to diary and annual changes on ambient conditions, is analyzed and the main balance equations to describe the system behaviour are introduced. Then, dierent biological and structural models validated in industrial plants will be presented. Subsequently, the existing control problems in these systems are described, introducing a wide set of control algorithms that have been experimentally evaluated in industrial reactors. Finally, the most relevant aspects discussed along the paper are summarized., [ES] Este artículo presenta una visión general sobre el proceso de producción de microalgas desde un punto de vista de modelado y control de procesos. En primer lugar se exponen las ventajas y el potencial de este tipo de microorganismos, así como los distintos tipos de reactores que se suelen utilizar para su producción. Posteriormente, se analiza el comportamiento dinámico de este tipo de procesos, el cual es muy complejo y cambiante debido a variaciones en las condiciones ambientales tanto diarias como anuales, y se presentan los distintos balances que permiten describir la evolución de las principales variables del sistema. Se exponen distintos tipos de modelos a nivel biológico y a nivel estructural que han sido validados a escala industrial. Tras analizar su comportamiento dinámico, se motivan los distintos problemas de control existentes en este tipo de sistemas y se resume una amplia batería de estrategias de control que han sido evaluadas con éxito en fotobiorreactores industriales. Finalmente, se concluye el trabajo con un balance de los aspectos más importantes expuestos a lo largo del mismo.

This paper compares the effects of exposure to exogenous melatonin (MEL), short days (SD, 8. h of light) and long days (LD, 16. h of light), on reproductive activity, sperm motility and other reproductive variables, in Blanca Andaluza bucks. Fourteen males were spilt into two groups of seven animals (G1 and G2). They were subjected to five alternations of 2 months of LD followed by 2 months of SD or MEL before the experimental period of three consecutive intervals of (1) 2 months of SD (G1, N=. 7) or MEL (G2, N=. 7); (2) 2 months of LD (G1. +. G2, N=. 14); and (3) 2 months of SD (G2, N=. 7) or MEL (G1, N=. 7). Plasma testosterone concentration, live weight, testicular weight and fresh semen quality were determined weekly. Semen was also cooled and frozen-thawed every fortnight, and the same quality variables measured as for fresh sperm. When the bucks were under LD treatment, the testosterone concentration was lower than when under MEL or SD treatment (. P<. 0.01); values for the semen concentration and total number of sperm per ejaculate were also higher (. P<. 0.001). No differences were observed between the MEL and SD treatments in terms of fresh, cooled or frozen-thawed sperm quality. Only some quality variables on fresh semen were improved by MEL and SD treatment (. P<. 0.05). In conclusion the results of the present experiment showed that MEL improved the fresh semen motility variables, but this did not improve the motility of frozen-thawed sperm over that recorded for either SD or LD treatment. © 2015 Elsevier B.V.

Interest in the preservation of endangered breeds such as the Blanca Andaluza goat, has increased and some steps should be therefore taken to ensure it. The study was designed to determine the seasonal reproductive pattern of Blanca Andaluza bucks, and whether this affects the quality of their semen and its freezability over the year. Seven bucks were used and their body weight, testicular weight, plasma testosterone concentration and fresh sperm quality determined every week. The collected sperm was cryopreserved and stored; it was then thawed and the same sperm quality variables measured every fortnight. High plasma testosterone concentrations were recorded during the summer and autumn, and low concentrations were recorded during winter and spring (p<0.001). No differences were seen between seasons in terms of the percentage of bucks ejaculating, the percentage of active bucks, or ejaculate volume. However, the sperm concentration, the total number of sperm per ejaculate, and the values for most fresh sperm variables were lower during the winter period (at least p<0.05). After freezing-thawing, the quality of winter-collected sperm was better, in some respects, than that of summer-collected sperm (at least p<0.05). These results reveal that Blanca Andaluza bucks show seasonal reproductive activity in terms of their plasma testosterone concentration, but no clear change in their sexual behaviour between seasons was observed. The values of fresh sperm variables also vary over the year, reaching their lowest during winter. However, after freezing-thawing, winter-collected sperm is of overall better quality than sperm collected during the summer. © 2015 INIA.

This article presents the design and development of an embedded automatic pressure-control system for a mobile sprayer working in greenhouses. The pressure system is mounted on a commercial vehicle, it is composed of two on/off electrovalves and one proportional electrovalve. The hardware developed is based on an embedded microprocessor and provides a low-cost and robust solution. The resulting embedded system has been tested on a spraying system mounted on a manned vehicle. Furthermore, an easy-tuning non-linear PI (Proportional Integral) controller to achieve the desired pressure profile is designed and implemented in the embedded system. Many physical experiments show the best performance of such controller compared with a typical PI controller. Experiments covering the pressure range from 2 to 14 bar obtained a mean error less than 0.3 bar. Summing up, a low-cost automatic pressure-control system is developed, it ensures a uniform decomposition of the liquid sprayed on plants, and it works properly over a wide variable-pressure range.

[ES] Este trabajo presenta un laboratorio virtual para la enseñanza del control climático de invernaderos. Con este tipo de herramientas se tiene como objetivo conseguir la abstracción de trabajos de investigación consolidados con el fin de que puedan ser utilizados por los estudiantes de forma sencilla y transparente. Concretamente la herramienta desarrollada en este artículo aporta un modelo completo de invernadero con un conjunto de controladores específicos, todo ello accesible a través de una interfaz gráfica estructurada. De esta forma se permite a los alumnos poner en práctica los conocimientos teóricos adquiridos en clase sin restricciones espacio-temporales.

[EN] Most of the time, people perform their daily activities within buildings, making it necessary to monitor the conditions of comfort (thermal, visual and air quality) within them, trying to minimize energy consumption simultaneously. A review of techniques for comfort control in building is presented in this work. The paper also shows tesults obtained in the implementation of a hierarchical control system, which provides adequate thermal comfort inside the CDdI-CIESOL-ARFRISOL (Research Container Demonstrator – Centre for Solar Energy Research – Strategic Singular Project ARFRISOL) of the University of Almería., [ES] La mayor parte del tiempo, las personas realizan sus actividades cotidianas en el interior de edificios, siendo por tanto preciso controlar las condiciones de confort (térmico, visual y calidad de aire) en el interior de los mismos, intentando minimizar el consumo energético simultáneamente. Este trabajo presenta una revisión de técnicas de control del confort en edificios. También muestra los resultados obtenidos en la implementación de un sistema de control jerárquico, que permite obtener situaciones de confort térmico adecuadas en el interior del CDdI-CIESOL-ARFRISOL (Contenedor Demostrador de Investigación - Centro de Investigación de la Energía Solar - Proyecto Singular Estratégico ARFRISOL) de la Universidad de Almería.

[ES] Este trabajo presenta un laboratorio virtual para la enseñanza del control climático de invernaderos. Con este tipo de herramientas se tiene como objetivo conseguir la abstracción de trabajos de investigación consolidados con el fin de que puedan ser utilizados por los estudiantes de forma sencilla y transparente. Concretamente la herramienta desarrollada en este artículo aporta un modelo completo de invernadero con un conjunto de controladores específicos, todo ello accesible a través de una interfaz gráfica estructurada. De esta forma se permite a los alumnos poner en práctica los conocimientos teóricos adquiridos en clase sin restricciones espacio-temporales.