Reliability-based economic model predictive control for generalized flow-based networks including actuators' health-aware capabilities

This paper proposes a reliability-based economic model predictive control (MPC) strategy for the management of generalized flow-based networks, integrating some ideas on network service reliability, dynamic safety stock planning, and degradation of equipment health. The proposed strategy is based on a single-layer economic optimisation problem with dynamic constraints, which includes two enhancements with respect to existing approaches. The first enhancement considers chance-constraint programming to compute an optimal inventory replenishment policy based on a desired risk acceptability level, leading to dynamically allocate safety stocks in flow-based networks to satisfy non-stationary flow demands. The second enhancement computes a smart distribution of the control effort and maximises actuators’ availability by estimating their degradation and reliability. The proposed approach is illustrated with an application of water transport networks using the Barcelona network as the considered case study.Peer ReviewedPostprint (author's final draft

Incentivos fiscales para la creación de empleo

El sistema tributario, los tributos que lo conforman y sus técnicas liquidatorias, además de ser medios para recaudar ingresos públicos, ha de servir como instrumento de política económica general, atender a las exigencias de estabilidad y progreso social y procurar una mayor distribución de la renta nacional. Estas funciones extrafiscales de las técnicas tributarias pueden configurarse como un instrumento de primer orden para que los poderes públicos cumplan con el mandato constitucional de realizar una política orientada al pleno empleo. En el presente trabajo se analizan dos medidas previstas en nuestro ordenamiento tributario que inciden en la dirección indicada: la libertad de amortización que fomenta las inversiones generadoras de empleo y los beneficios fiscales con los que cuentan los empresarios por creación de empleo de trabajadores minusválidos.____________________________The tax system, the taxes that it collects, and the means by which tax settlements are made as well as being ways of gathering public funds, have a role to play in economic policy in as much as they meet needs in terms of stability and social progress, and try to achieve a better distribution of gross national income. These extra fiscal functions attributed to the tax collecting system can be turned into one of the principal instruments in the hands of public authorities enabling them to fulfil their constitutional duty to carry out policies that will lead to full employment

Thermal resting pattern and acute skin temperature response to exercise in older adults: Role of cardiorespiratory fitness

Background Infrared thermography is a growing area of interest in sports science due to the potential of skin temperature (Tsk) measurements to provide valuable information from rest to exercise. However, limited research exists on Tsk in older adults and the impact of factors such as sex and cardiorespiratory fitness (CRF) on Tsk. This study aims to investigate Tsk at rest and after acute exercise in older adults and assess whether sex or CRF influences Tsk. Methods Ninety-two participants (41 women, 68.48 ± 3.01 years) were examined with a thermographic camera in a conditioned room (23.02 ± 3.01 °C) at rest and after a graded protocol. The Tsk of 25 regions of interest (ROIs) were extracted and analysed. Results Men had higher overall Tsk at rest in 76% of ROIs, showing significant differences (p < 0.010) in six specific ROIs, independent of CRF. Both sexes had similar Tsk responses after graded exercise, with increases in distal parts (1.06 ± 0.50 °C), decreases in proximal parts (−0.62 ± 0.42 °C), and stable central Tsk (0.23 ± 0.59 °C). Increases in lower limb Tsk were significantly associated with CRF in men and women (β = 0.438, p = 0.001, and β = 0.535, p < 0.001, respectively), explaining 17% and 27% of the variance, respectively. Conclusions This study demonstrates a sex-specific effect on resting Tsk in older adults, suggesting that sex-specific Tsk patterns should be considered when analysing Tsk in this population. Additionally, the association between increases in lower limb Tsk and CRF suggests that Tsk could be a promising predictor of CRF in older adults.Spanish Ministry of Economy, Industry and Competitiveness (MINECO)European Regional Development Fund (FEDER) (grant number: DEP 2016-76123-R)FEDER/ Junta de Andalucía-Consejeria de Salud y Familias (grant number PI- 0002-2017)Biomedical Research Networking Center on Frailty and Healthy Aging (CIBERFES)FEDER funds from the European Union (CB16/10/00477)Margarita Salas Postdoctoral ProgramEuropean Union Next GenerationE

Desarrollo y primeros resultados de una aplicación móvil para la pre-inspección de equipos de tratamientos fitosanitarios

Congreso Agroingeniería 2015. Orihuela (Alicante). 1 a 3 de junio de 2015Por todos es conocido que el presente y futuro de las aplicaciones de productos agroquímicos pasa por una buena regulación, calibración y mantenimiento de los equipos que se utilizan. Tanto Europa como los países miembros y sus comunidades autónomas, en el caso de España, a través de sus instituciones (Universidades, Consejerías, etc.), están trabajando concienzudamente en el protocolo de inspección. Es de prever que en muchos equipos la primera inspección será desfavorable, y además supondrá un coste económico alto para el propietario, independientemente de que el equipo pase la inspección de forma favorable o no. Este hecho hace que no se conciba este control con la “percepción beneficiosa” que pueda tener la administración. Por todo ello, este equipo de trabajo ha decidido centrarse en el término “preinspección” y desarrollar una aplicación gratuita de autocontrol para dispositivos móviles que permita al propietario o su técnico agrícola conocer el estado de su máquina antes de acudir a una inspección “oficial” y de esta forma solventar los posibles problemas detectados. Para su desarrollo se ha usado programación orientada a objetos (POO) con Java en entorno Android. En los primeros equipos que han formado parte de este estudio se ha conseguido, por una parte poner en conocimiento y mostrar los elementos y aspectos a controlar y por otra, generar de forma gratuita y fácil un informe donde se indica los elementos y aspectos a solventar antes de ir a una inspección. Está aplicación de pre-inspección ha sido una herramienta muy valorada por los usuarios como mantenimiento preventivo.It is widely acknowledged that the present and future practice of pesticide applications requires good regulation, calibration and maintenance of the equipment used. European countries and their regional governments, in the case of Spain, through its institutions (Universities, Councils, etc.), are working conscientiously towards inspection protocol. It is expected that many sprayers will not pass the first inspection, and there will be a significant cost to the owner, whether the equipment passes the inspection or not. This fact makes this inspection protocol is not conceived with the "beneficial perception" as the administration may have. Therefore, this research group has decided to focus on the term “pre-inspection” and develop a free mobile application for selfassessment that allows the owner or agricultural technician check the status of the sprayer before inspection. This would address the possible problem identified. The application was written in an object oriented programming language (OOP) – Java – for an Android platform. For the first sprayers considered in this study there have been several achievements: firstly informing about and showing those elements and aspects of the sprayer which need to be controlled and secondly, generating simply and without cost a report describing those elements and aspects which must be resolved before going for an inspection. This approach to pre-inspection has proved to be highly very valued by users as a tool for preventive maintenance

Students’ dedication in a cooperative, project-based learning context: measurements, analysis and implications

Discovering the effort students devote to their studies is of key importance for an appropriate design of courses and syllabus. Although over the last years many studies have been carried out in this respect, few of them have focused on the more complex cases of cooperative and project-based learning. The main contributions of our work are: (i) the investigation of the connection between students’ work habits and the learning methodologies being used; (ii) the usage of a web application to make easier data gathering and analysis; and (iii) the validation of students-provided data so that better conclusions can be derived

Partición de energía en procesos unimoleculares, procesos primarios y partición de energía enla fotolisis de varios diazoalcanos y diazirinas alifáticas, construcción de un láser químico

Tesis inédita de la Universidad Complutense de Madrid, Facultad de Ciencias Químicas, leída en 1975.Fac. de Ciencias QuímicasTRUEProQuestpu

Universal prototype for adapting from conventional centrifugal fertilizer to variable-rate spreader

Congreso Agroingeniería 2015. Orihuela (Alicante). 1 a 3 de junio de 2015La Agricultura de Precisión constituye un nuevo paradigma en la agricultura de hoy. A objetivos como el aumento de la productividad o de la eficiencia económica, se les unen otros en auge como el respeto medioambiental y un riguroso control en la seguridad alimentaria. En general las técnicas de agricultura de precisión requieren de un mejor conocimiento de las necesidades del cultivo y del suelo, y también del empleo de la maquinaria más adecuada que tenga en cuenta la variabilidad espacial y temporal en las necesidades de los cultivos. En este contexto, este estudio tiene como objetivo principal, el diseño, desarrollo y evaluación de una plataforma universal para controlar una abonadora centrífuga convencional mediante un monitor comercial inicialmente diseñado para el control de barras de pulverización de productos líquidos, lo que permite la adaptación dinámica de la cantidad de fertilizante sólido según las necesidades reales del cultivo. Para el desarrollo del sistema de control fue necesario realizar una caracterización de la abonadora mediante pruebas de calibración del sistema dosificador. También se han desarrollado los distintos módulos de hardware (módulo para el control de los discos, interacción con el sistema de control de líquidos comercial, etc.) necesarios para automatizar las acciones que se realizan durante el funcionamiento de la máquina. Para la gestión del sistema se utiliza la plataforma de hardware libre de bajo coste Arduino que resulta fácilmente adaptable para otras abonadoras, desarrollando un software capaz de gestionar el resto de componentes. Finalmente se monta todo el conjunto a bordo del tractor y se realizan las pruebas de funcionamiento. Se comprobó que el sistema trabaja correctamente, con una respuesta adecuada, consiguiendo automatizar el proceso de variar la dosis durante la marcha de forma eficaz.Como se observa en estos primeros resultados, la utilización de este equipo como elemento importante en una aplicación variable de insumos, puede suponer una reducción económica y del impacto medioambiental de la operación, además de permitir una distribución mas racional del nitrógeno u otros fertilizantes en campo, algo sin duda de especial relevancia en sistemas modernos de producción.Precision Agriculture represents a new paradigm in modern agriculture. To objective such as increasing productivity and economic efficiency, are joined other arising objective as the environmental concern. Precision agriculture techniques require a better understanding of crop and soil needs, and the use of precise machinery that take into account the spatial-temporal variability across fields. In these terms, the goal of this study was the design, development and evaluation of a universal platform to control a conventional disc fertilizer spreader, and thus able to manage the amount of fertilizer on the go. A specific on-field calibration was necessary to determine the spreader settings for a given type of fertilizer. The components of the hardware modules (control system of disks, interaction with sections control system, etc.) capable of automating actions performed in operation of the spreader were developed. The control system was developed based on an open-source and low-cost microcontroller-board (Arduino), which could be adapted easily to other spreader model, and a firmware capable to control the hardware components. Once installed on-board, field tests were provided to investigate the proper functioning and response time (approx. 1 sec) of the control system and achieve automate the process of varying the fertilizer dose on the go. As noted these preliminary results, the utilization of this prototype as an essential part of a variable input application may found an economic reduction in fertilizer operation and environmental impact, and allows the control of nitrogen or other fertilizer in fields, techniques that definitely significant in modern agriculture production systems

A distributed predictive control approach for periodic flow-based networks: application to drinking water systems

This paper proposes a distributed model predictive control approach designed to work in a cooperative manner for controlling flow-based networks showing periodic behaviours. Under this distributed approach, local controllers cooperate in order to enhance the performance of the whole flow network avoiding the use of a coordination layer. Alternatively, controllers use both the monolithic model of the network and the given global cost function to optimise the control inputs of the local controllers but taking into account the effect of their decisions over the remainder subsystems conforming the entire network. In this sense, a global (all-to-all) communication strategy is considered. Although the Pareto optimality cannot be reached due to the existence of non-sparse coupling constraints, the asymptotic convergence to a Nash equilibrium is guaranteed. The resultant strategy is tested and its effectiveness is shown when applied to a large-scale complex flow-based network: the Barcelona drinking water supply system.Peer ReviewedPostprint (author's final draft

A service reliability model predictive control with dynamic safety stocks and actuators health monitoring for drinking water networks

This paper presents a model predictive control strategy to assure reliability in drinking water networks given a customer service level and a forecasting demand. The underlying idea concerns a two-layer hierarchical control structure. The upper layer performs a local steady-state optimization to set up an inventory replenishment policy based on dynamic safety stocks for each tank in the network. At the same stage, actuators health is revised to set up their next maximum allowable degradation in order to efficiently distribute overall control effort and guarantee system availability. In the lower layer, a model predictive control algorithm is implemented to compute optimal control set-points to minimize a multiobjective cost function. Simulation results in the Barcelona drinking water network have shown the effectiveness of the dynamic safety stocks allocation and the actuators health monitoring to assure service reliability and optimizing network operational costs.Peer ReviewedPostprint (author’s final draft

Vertebral Osteonecrosis

Vertebral osteonecrosis (ON) is a rare, underdiagnosed disease, also called pseudarthrosis due to ischemia following a compression fracture (CF). The main features include the air-occupied intravertebral cleft visualized as a radiolucent shade of linear or semilunar X-ray, namely an intravertebral vacuum cleft (IVC) sign. Usually, this phenomenon shows low signal intensity with all magnetic resonance imaging (MRI) sequences. Another feature of ON of the vertebral body is the intravertebral fluid analogous to edema and fibrosis in histological sections. This appears as low signal intensity on T1-weighted MRI, with high signal intensity on T2-weighted images. The risk factors for vertebral ON are multivariate, and the pathophysiological mechanisms are still unknown with certainty