Generic Battery Model based on a Parametric Implementation

Batteries are a common element used in many electronic applications. Therefore, the analysis and simulation of these applications requires a battery model in order to validate the behavior of the whole system. Since batteries are based on different technologies, a modeling approach valid for any technology is a potential good alternative. Since there are similarities among the different technologies, it is possible to address the modeling of batteries as generic energy storage elements with particular differences. This work presents a battery model valid for different technologies based on a parametric implementation

Using Mobile Devices for Improving Learning Outcomes and Teachers’ Professionalization

Teaching in higher education is changing due to the influence of technology. More and more technological tools are replacing old teaching methods and strategies. Thus, mobile devices are being positioned as a key tool for new ways of understanding educational practices. The present paper responds to a systematic review about the benefits that mobile devices have for university students’ learning. Using inclusion and exclusion criteria in theWeb of Science and Scopus databases, 16 articles were selected to argue why Mobile learning (Mlearning) has become a modern innovative approach. The results point to an improvement in students’ learning through Mlearning, factors that encourage the use of mobile devices in universities have been identified, and e ective mobile applications in improving teaching and learning processes have been presented. The inclusion of this methodology requires a new role for teachers, whose characterization is also specified

Evaluación de ideas previas de estadística y probabilidad en futuros profesores de primaria ante la prueba PISA

La estadística descriptiva y la combinatoria y probabilidad son aspectos de la competencia matemática muy importantes en la educación de los estudiantes de primaria. Generalmente, los conocimientos relacionados con esta parte de la matemática suelen pasar a un segundo plano en las enseñanzas de Educación Primaria. Los contenidos que se suelen enseñar a los estudiantes sobre estas materias suelen ser muy genéricos sin llegar a profundizar en los conceptos estadísticos y en una correcta interpretación de los conceptos probabilísticos. Hay que considerar que en la actual sociedad de la información se ofrecen multitud de noticias y datos que se consideran como fiables y que informan sobre la situación de determinados aspectos de la vida diaria. Sin embargo, hay que tener en cuenta que también se da información sobre hechos no previsibles o con un resultado, cuando menos, incierto; por ejemplo, datos sobre la bolsa, predicciones meteorológicas, proyección de intención de voto en las elecciones y otras muchas informaciones en los que la incertidumbre es la principal de sus características. Por ello, se considera imprescindible incluir las ramas de Estadística y Probabilidad en los currículos escolares. El objetivo de este trabajo es ver el grado de conocimiento que los futuros profesores de Educación Primaria tienen sobre estadística descriptiva y sobre combinatoria y probabilidad. Para ello se les ha pasado un cuestionario con 9 preguntas liberadas del informe PISA 2012, y se han analizado los resultados comparándolos con los resultados obtenidos en alumnos en España y en países miembros de la OCDE. Se ha intentado ver la influencia del sexo y del tipo de Bachillerato cursado por los estudiantes del Grado en Educación Primaria en los resultados obtenidos.Universidad de Granada. Facultad de Ciencias de la Educación. Grado en Educación Primari

Design and Implementation of Acoustic Source Localization on a Low-Cost IoT Edge Platform

The implementation of algorithms for acoustic source localization on edge platforms for the Internet of Things (IoT) is gaining momentum. Applications based on acoustic monitoring can greatly benefit from efficient implementations of such algorithms, enabling novel services for smart homes and buildings or ambient-assisted living. In this context, this brief proposes extreme low-cost sound source localization system composed of two microphones and the low power microcontroller module ESP32. A Direction-Of-Arrival (DOA) algorithm has been implemented taking into account the specific features of this board, showing excellent performance despite the memory constraints imposed by the platform. We have also adapted off-the-shelf lowcost microphone boards to the input requirements of the ESP32 Analog-to-Digital Converter. The processing has been optimized by leveraging in parallel both cores of the microcontroller to capture and process the audio in real time. Our experiments expose that we can perform real-time localization, with a processing time below 3.3 ms.This work was supported in part by the Spanish Government under Grant TIN2017-82972-R, Grant ESP2015-68245-C4-1-P, and Grant RTI2018-097045-B-C21, and in part by the Valencian Regional Government under Grant PROMETEO/2019/109

Practical considerations for acoustic source localization in the IoT era: Platforms, energy efficiency, and performance

The rapid development of the Internet of Things (IoT) has posed important changes in the way emerging acoustic signal processing applications are conceived. While traditional acoustic processing applications have been developed taking into account high-throughput computing platforms equipped with expensive multichannel audio interfaces, the IoT paradigm is demanding the use of more flexible and energy-efficient systems. In this context, algorithms for source localization and ranging in wireless acoustic sensor networks can be considered an enabling technology for many IoT-based environments, including security, industrial, and health-care applications. This paper is aimed at evaluating important aspects dealing with the practical deployment of IoT systems for acoustic source localization. Recent systems-on-chip composed of low-power multicore processors, combined with a small graphics accelerator (or GPU), yield a notable increment of the computational capacity needed in intensive signal processing algorithms while partially retaining the appealing low power consumption of embedded systems. Different algorithms and implementations over several state-of-the-art platforms are discussed, analyzing important aspects, such as the tradeoffs between performance, energy efficiency, and exploitation of parallelism by taking into account real-time constraintsThis work was supported in part by the Post-Doctoral Fellowship from Generalitat Valenciana under Grant APOSTD/2016/069, in part by the Spanish Government under Grant TIN2014-53495-R, Grant TIN2015-65277-R, and Grant BIA2016-76957-C3-1-R, and in part by the Universidad Jaume I under Project UJI-B2016-20.Publicad

Selection of the appropriate winding setup in planar inductors with parallel windings

The use of parallel windings in high frequency planar inductors is a common practice. Since the planar technology, commonly PCB layers, limits the maximum layer thickness, the use of parallel windings is usually required in order to reduce the current density and losses. The distribution of the current through each parallel winding depends on the winding positioning and the frequency effects. This effect is especially important in gapped inductors, because the energy stored in the gap region determines the current distribution through the windings. Therefore, the winding positioning is a critical task in order to obtain a balanced current distribution through all the parallel winding

Automatized connection of the layers of planar transformers with parallel windings to improve the component behavior

Transformers with parallel windings are commonly used to reduce the losses in the windings. Windings losses depend on the winding positioning and the frequency effects because each winding affects the current sharing of itself and the neighboring windings. In this paper a methodology for determining the connections of the parallel windings that reduces the power losses (and temperature) in the windings of multi-winding transformers is presented. Other applications of the method, such as balanced current sharing and voltage drop reduction are also explored. In this paper a methodology for determining the connections of the parallel windings that reduces the power losses (and temperature) in the windings of multi-winding transformers is presented. Other applications of the method, such as balanced current sharing and voltage drop reduction are also explored

Analysis of Spatial and Temporal Variability of the PAR/GHI Ratio and PAR Modeling Based on Two Satellite Estimates

The main objectives of this work are to address the analysis of the spatial and temporal variability of the ratio between photosynthetically active radiation (PAR) and global horizontal irradiance (GHI), as well as to develop PAR models. The analysis was carried out using data from three stations located in mainland Spain covering three climates: oceanic, standard Mediterranean, and continental Mediterranean. The results of this analysis showed a clear dependence between the PAR/GHI ratio and the location; the oceanic climate showed higher values of PAR/GHI compared with Mediterranean climates. Further, the temporal variability of PAR/GHI was conditioned by the variability of clearness index, so it was also higher in oceanic than in Mediterranean climates. On the other hand, Climate Monitoring Satellite Facility (CM-SAF) and Moderate-Resolution Imaging Spectroradiometer (MODIS) data were used to estimate PAR as a function of GHI over the whole territory. The validation with ground measurements showed better performance of the MODIS-estimates-derived model for the oceanic climate (root-mean-square error (RMSE) around 5%), while the model obtained from CM-SAF fitted better for Mediterranean climates (RMSEs around 2%)This work was funded by the Ministry of Economy, Industry and Competitiveness (MINECO) [Project CGL2016-79284-P AEI/FEDER/UE and F.F.-C. was founded by PhD Contract Number BES-2017-082043]S

Power losses calculations in windings of gapped magnetic components

A model is proposed for the calculation of the winding losses at the beginning of the design process of high frequency transformers and inductors. Although this kind of losses have been subject of investigation for years, their analytical calculation in gapped components is still limited, and the use of numerical analysis tools, such as finite elements analysis (FEA) tools, are commonly needed for winding characterization. A general 2-D equivalent analytical model for windings losses calculation in gapped magnetic components that shows very good results compared with FEA calculation is presented. The model can be integrated in design and optimization tools in order to evaluate the influence of the gap on the windings at the very early stages of the design process

Simple analytical approach for the calculation of winding resistance in gapped magnetic components

The Dowell expression is the most commonly used method for the analytic calculation of the equivalent resistance in windings of magnetic components. Although this method represents a fast and useful tool to calculate the equivalent resistance of windings, it cannot be applied to components that do not fit with classical 1D assumption, which is the case of gapped magnetic components. These structures can be accurately analyzed using finite-element analysis (FEA) with the time cost that this represents. Modifying the Dowelĺs equation, and taking advantage of the orthogonality between skin and proximity effects, a simple solution that allows its application in gapped magnetic components is proposed in this work, which results shows a very good accuracy compared with experimental measurements