Comparison of organic packing materials for toluene biofiltration

he paper focuses on the operation of a pilot plant with four biofilters operated in parallel for determining the suitability of coconut fiber, peat, compost from the digested sludge of a wastewater treatment plant and pine leaves as packing materials for biofiltration of toluene. Physical characteristics of packing materials such as specific surface area, density, pore size and elemental composition were determined for each packing material. Biological activity and packing capabilities related to toluene removal were determined during the startup and operation of the four biofilters under different conditions of nutrients, watering and inlet air relative humidity supply. Nutrient addition was key in improving removal efficiency (RE) and elimination capacity (EC) of biofilters. Feeding of medium with nutrients increased the RE and the EC by a factor of 2 to 4 than these found when supplying only tap water. Additionally, when extra nitrogen was supplied in the medium, RE and EC increased by a factor of 2. Nutrient addition also lead to a microbial population change from bacterial to fungal biofilters. It was denoted that watering control is necessary to improve fungal biofilters performance in terms of ensuring a proper washout of acidic by-products to avoid fungi inhibition and consequent lowered removal capacities.Peer ReviewedPostprint (published version

Tiempo de fotogrametría. Una propuesta de clasificación para el levantamiento fotogramétrico

The graphic survey of the built heritage allows and makes possible a graphic territory of learning, analysis, experimentation, communication and deposit for architecture. It supposes, in addition to the connection between the theory and the practice of our discipline, an excellent framework for teaching. In this context, photogrammetry is evidenced as a rigorous and efficient technique that, at the service of relevant hypotheses, is capable of producing results that are as valuable as they are contemporary. This research paper, created after the tutelage of more than forty final degree projects that use the photogrammetric technique, develops a classification proposal for qualified point clouds (as part of the technique workflow) based on the temporal nature of the drawings. In this way we will argue the three possible positions (previous or tool, intermediate or process and later or result) to conclude by claiming the relevance and importance of their consideration during the value of the drawings of the built architecture.El levantamiento del patrimonio construido permite y hace posible un territorio gráfico de aprendizaje, análisis, experimentación, comunicación y depósito para la arquitectura. Supone, además de la conexión entre la teoría y la práctica de nuestra disciplina, un marco inmejorable para la enseñanza. En este contexto la fotogrametría se evidencia como una técnica rigurosa y eficaz que, al servicio de unas hipótesis pertinentes, es capaz de producir resultados tan valiosos como contemporáneos. El presente artículo de investigación, producido tras la tutela de más de cuarenta trabajos finales de grado que emplean la técnica fotogramétrica, desarrolla una propuesta de clasificación para las nubes de puntos cualificados (parte del flujo de trabajo de la técnica) atendiendo al carácter temporal de la grafía. De esta forma argumentaremos las tres posibles posiciones (anterior o herramienta, intermedia o proceso y posterior o resultado) para concluir reivindicando la pertinencia e importancia de su consideración durante la puesta en valor de los dibujos de la arquitectura construida.This work is developed as part of an R+D+I project entitled “The representation of time in graphic expression”, with reference project-emergent-GRE18-10 and funded, in public concurrence, by the Vice-Rector’s Office for Research and Transfer of Knowledge of the University of Alicante

Asimetría de la información en la contratación con las sociedades extranjeras en Colombia

Especialista en Derecho ComercialEspecializació

Study of NH3 removal by gas-phase biofiltration: effects of shock loads and watering rate on biofilter performance

Ammonia biofiltration performance under shock loads episodes was studied in a reactor packed with coconut fiber as carrier material. Periodical gas and leachate samplings were analyzed and used to characterize the biofilter performance in terms of removal efficiency (RE) and elimination capacity (EC). Nitrogen fractions in the leachate were quantified to identify the experimental rates of nitritation and nitratation.. In a primary experiment a sudden increment of ammonia load was applied for 1 day by changing the ammonia inlet load from 5.2 to 29.1 g N.m-3.h-1. Even though stable operation was obtained (RE of 99.9%), a notable accumulation of nitrite was verified in the leachate. Experimental rates showed that nitritation increased at the same the same ratio that ammonia load was varied. However the nitratation seemed to be largely affected by high ammonia and nitrite concentration. In a subsequent experiment varying the inlet ammonia load, the system was rapidly recovered by increasing the watering rate. Since ammonia was partially removed by physicochemical process as observed in previous experiments, a final experimental was conducted to improve the nitritation capacity. The addition of inorganic carbon source demonstrated to enhance the capacity of the biofilter to degrade a higher amount of ammonia.Peer ReviewedPostprint (published version

Stochastic Model Predictive Control Approaches applied to Drinking Water Networks

Control of drinking water networks is an arduous task given their size and the presence of uncertainty in water demand. It is necessary to impose different constraints for ensuring a reliable water supply in the most economic and safe ways. To cope with uncertainty in system disturbances due to the stochastic water demand/consumption, and optimize operational costs, this paper proposes three stochastic model predictive control (MPC) approaches, namely: chance-constrained MPC, tree-based MPC, and multiple scenarios MPC. A comparative assessment of these approaches is performed when they are applied to real case studies, specifically, a sector and an aggregate version of the Barcelona drinking water network in Spain

Characterization of organic packing materials in the removal of ammonia gas in automated biofilters

A fully-automated pilot-scale biofilter filled with coconut fiber as packing material was investigatedfor treatment of ammonia-containing off-gas streams. Coconut fiber was completely characterized forphysical and chemical parameters and biological activity. Biofilter performance was assessed in a pilot-scale unit in a set of continuous experiments varying the inlet ammonia concentration in a range of 45 to240 ppmv at a gas contact time of 36 seconds. Samples taken along the bed height as well as inlet and outletammonia concentrations were used to determine a maximum elimination capacity of 12 g NH3m?3h?1ata 80% removal efficiency. Some features related to nitrification inhibition encountered in the experimentsare also discussed.Peer ReviewedPostprint (published version

Coalitional model predictive control of parabolic-trough solar collector fields with population-dynamics assistance

Parabolic-trough solar collector fields are large-scale systems, so the application of centralized optimizationbased control methods to these systems is often not suitable for real-time control. As such, this paper formulates a novel coalitional control approach as an appropriate alternative to the centralized scheme. The key idea is to split the overall solar collector field into smaller subsystems, each of them governed by a local controller. Then, controllers are clustered into coalitions to solve a local optimization-based problem related to the corresponding subset of subsystems, so that an approximate solution of the original centralized problem can be obtained in a decentralized fashion. However, the operational constraints of the solar collector field couple the optimization problems of the multiple coalitions, thus limiting the ability to solve them in a fully decentralized manner. To overcome this issue, a novel population-dynamics-assisted resource allocation strategy is proposed as a mechanism to decouple the local optimization problems of the multiple coalitions. The proposed coalitional methodology allows to solve the multiple local subproblems in parallel, hence reducing the overall computational burden, while guaranteeing the satisfaction of the operational constraints and without significantly compromising the overall performance. The effectiveness of proposed approach is shown through numerical simulations of a 10- and 100-loop version of the ACUREX solar collector field of Plataforma Solar de Almería, Spain.Peer ReviewedPostprint (published version

Viejas aunque “nuevas” metodologías de enseñanza-aprendizaje: los talleres de experimentación lítica prehistórica como herramienta de formación

Explicar y comprender la Historia de la Humanidad requiere conocer cómo y qué herramientas se fueron elaborando a lo largo de más de 2,5 millones de años. Una parte importante de dichos instrumentos se fabricaron durante la Prehistoria usando diferentes tipos de rocas. Así, entre los contenidos curriculares incluidos en los grados en Historia y en másteres afines en España, destacan diversas nociones sobre tecnología e instrumental lítico prehistórico, con los que se intenta que el alumnado conozca los procesos de producción lítica tallada, su evolución tecnológica y tipológica, y los procesos de clasificación y análisis. El empleo de material gráfico como recurso docente, se viene mostrando insuficiente para conseguir buenos resultados de aprendizaje. El desarrollo de talleres de experimentación lítica tallada sobre instrumental prehistórico constituye la mejor metodología de enseñanza-aprendizaje con la que mostrar e interactuar con los estudiantes, aunque dicha actividad requiere de una serie de condiciones de difícil consecución. La experiencia llevada a cabo en asignaturas del Grado en Historia y del Máster en Arqueología Profesional y Gestión del Patrimonio de la UA, es un claro ejemplo de evaluación de las fortalezas y debilidades de la implementación de dichos talleres

Levodopa-Induced Dyskinesia in Parkinson Disease Specifically Associates with Dopaminergic Depletion in Sensorimotor-Related Functional Subregions of the Striatum

[Purpose] To determine whether the development of levodopa-induced dyskinesia (LID) in Parkinson disease (PD) specifically relates to dopaminergic depletion in sensorimotor-related subregions of the striatum.[Methods] Our primary study sample consisted of 185 locally recruited PD patients, of which 73 (40%) developed LID. Retrospective 123I-FP-CIT SPECT data were used to quantify the specific dopamine transporter (DAT) binding ratio within distinct functionally defined striatal subregions related to limbic, executive, and sensorimotor systems. Regional DAT levels were contrasted between patients who developed LID (PD + LID) and those who did not (PD-LID) using analysis of covariance models controlled for demographic and clinical features. For validation of the findings and assessment of the evolution of LID-associated DAT changes from an early disease stage, we also studied serial 123I-FP-CIT SPECT data from 343 de novo PD patients enrolled in the Parkinson Progression Marker’s Initiative using mixed linear model analysis.[Results] Compared with PD-LID, DAT level reductions in PD + LID patients were most pronounced in the sensorimotor striatal subregion (F = 5.99, P = 0.016) and also significant in the executive-related subregion (F = 5.30, P = 0.023). In the Parkinson Progression Marker’s Initiative cohort, DAT levels in PD + LID (n = 161, 47%) were only significantly reduced compared with PD-LID in the sensorimotor striatal subregion (t = −2.05, P = 0.041), and this difference was already present at baseline and remained largely constant over time.[Conclusion] Measuring DAT depletion in functionally defined sensorimotor-related striatal regions of interest may provide a more sensitive tool to detect LID-associated dopaminergic changes at an early disease stage and could improve individual prognosis of this common clinical complication in PD.Peer reviewe

Códigos gráficos entre la figuración y la abstracción. Innovación e investigación docente en E.G.A. dentro del E.E.E.S.

El artículo presenta algunos de los aspectos investigados en el seno de la Red “Codificación gráfica en los dibujos de ideación y abstracción arquitectónica, y en el uso de nuevas tecnologías” del curso académico 2013-2014 que se habían planteado al constituir la misma y que suponen una cierta continuidad con las ediciones anteriores del Proyecto Redes que ha venido desarrollando un grupo de profesores en el Área de Expresión Gráfica Arquitectónica (E.G.A.) en el Grado en Arquitectura de la U.A. dentro del contexto del E.E.E.S. Así se decidió centrar las investigaciones en torno al tema de los códigos gráficos pero en esta ocasión circunscrito al ámbito de las asignaturas de Análisis e Ideación Gráfica. En paralelo a esta iniciativa, en nuestra red veníamos planteando desde hacía algunos años la posibilidad de incluir a profesores de otras universidades que por su conocimiento en el ámbito de la investigación en los temas a abordar pudieran contribuir a enriquecer el debate en el seno de la misma. Así, con el cambio de normativa en esta edición del Proyecto Redes hemos podido contar con los doctores Javier Raposo Grau, de la Universidad Politécnica de Madrid, y Joel Olivares Ruiz, de la Universidad Gestalt de Diseño de Méjico, quienes han contribuido a las labores de la red. Hay al menos tres publicaciones presentadas a las XII Jornadas de Redes de Investigación en Docencia de la UA desarrolladas por profesores de la Red (Raposo 2014*, Marcos, Olivares, 2014*, Pablo Juan 2014*). La primera de ellas versa monográficamente acerca de los planteamientos docentes de las asignaturas de Dibujo, Análisis e Ideación 1 y 2 de la U.P.M.; las dos últimas se refieren, por un lado a las leyes de la Gestalt y a los códigos gráficos y, por otro, a la enseñanza de lo gráfico con herramientas digitales. Se ha decidido centrar, por ello, el discurso de esta investigación en el tema de los códigos gráficos en las asignaturas de Análisis e Ideación Gráfica 1 y 2 de la U.A. que pivotan entre la figuración y la abstracción