856 research outputs found
Desarrollo de dispositivos Bluetooth LE basados en CC2540/41
Gracias a su autonomía y a su bajo coste cada vez son más los dispositivos basados en la tecnología Bluetooth LE, desde termómetros inalámbricos o sensores para medir la presión sanguínea a dispositivos deportivos como relojes con GPS o sensores para runners.
El trabajo que aquí se propone consistirá en un estudio de la especificación Bluetooth LE profundizando en el funcionamiento de toda su pila de protocolos y su uso para la creación de aplicaciones.
Finalmente, como ejemplo, se desarrollará una aplicación de medida de la distancia respecto a una baliza a partir de la potencia de recepción de los paquetes BLE transmitidos por ésta.Thanks to its autonomy and its low cost, Bluetooth LE technology based devices are increasingly its use, from wireless thermometers or sensors for measuring blood pressure devices to sports watches with GPS or sensors for runners.
The work proposed here consist of a study of the Bluetooth LE specification deepen the operation of its entire protocol stack and its use to create applications.
Finally, as an example, an application for measuring the distance from a beacon using the reception power of the BLE packets transmitted by it will be developedGrado en Ingeniería Electrónica de Comunicacione
Investment in public transport projects in cities: What do citizens think about it?
In recent years, important public transport infrastructures projects have been carried out in Andalusia (Spain), some of them having an important impact on life in the metropolitan areas. Nevertheless, no studies have been done to know the citizens’ opinion concerning these projects. This article presents an analysis about the citizens’ perception on this matter, based on a 2015 survey with a sample of 1,200 individuals living in the Andalusian capital cities. Citizens’ perceptions about public transport infrastructures are analyzed, based on citizens’ mobility preferences, on their opinion about transport infrastructures’ social impact and about their adequation to the city they live in. Results indicate that people living in cities which already have underground have a larger preference for underground means of transport than those who live in cities that only have transit on surface. In addition, it is proved that light rail is the most unpopular transport mode among citizens.Agencia de Obra Pública de Andalucía y Unión Europea a través de "Herramienta para la evaluación previa de infraestructuras de transporte público" con código GGI3003IDIE con la colaboración de la Universidad de Granada y el Departamento de Ingeniería Civil de la Universidad de Granada
Citizens’ opinion about investment in public transport projects in cities
In recent times, the increasing demand for mobility has given rise to new projects for improved
public transport (PT) infrastructures. Such is the case of Andaluc ıa (Spain) where, since 2004, the
transit networks were improved and new underground and light rail systems were built. These
investments were made without taking into account the opinion of the citizens. In this context,
this paper expounds the results of a telephone survey conducted in 2015 to record citizens’ opinions
about the investment funneled into local transport infrastructures. The responses were analyzed
through decision trees, in order to identify groups of homogeneous characteristics and
common opinion. The results indicate that most citizens believed investment to have been insufficient,
even though nearly half the respondents affirmed the PT infrastructures in their city were
adequate. The results of the two majority opinion groups showed that: when citizens believe the
PT infrastructures of their city are not adequate, and they are not satisfied with key attributes of
the PT, they hold investment to be insufficient; in contrast, if citizens describe the PT infrastructure
as adequate, they appraise key aspects and support the use of public funding for financing the
PT, then they are satisfied with the investment made. Furthermore, some decision rules, and the
most influential variables in the study problem (PT infrastructures adequacy, coverage, being a
suburban bus user or not, and the support to use public funding for PT) were identified.This work was supported by the European Regional Development
Fund (ERDF) of European Union, and the Public Works Agency and
Regional Ministry of Public Works and Housing of the Regional
Government of Andalusia (Spain) (AOPJA) under Grant G-GI3003/
IDIE via the Researching Project “Tool for the preliminary evaluation
of PT infrastructures”
Ultrasound-Assisted Cold Alkaline Extraction: Increasing Hemicellulose Extraction and Energy Production from Populus Wood
Alkaline pretreatments are considered highly effective for the separation of the different
components of lignocellulosic biomass. However, cold alkaline extraction (CAE) exhibits minimal
modification/degradation of hemicellulosic fraction and successfully accomplishes efficient delignification.
In this research, the fast-growing clone AF2 of Populus x euramericana wood was utilized as the
raw material and subjected to ultrasound-assisted CAE. The objective of incorporating ultrasound
into cold alkaline extraction is to increase the yield of a hemicellulosic-rich liquid phase that can be
used to produce high-value products such as furfural or xylitol. Simultaneously, it aims to obtain a
solid phase with a higher calorific value compared to the raw material. The results, obtained from a
central composite factorial design, demonstrated that the CAE process for 90 min at a sodium hydroxide
concentration of 100 g L−1, a temperature of 30 ◦C, and with ultrasound assistance maximized
hemicellulose extraction in the liquid phase (60.8% was extracted) and improved the heating value of
solid phase.This work was funded by Spain’s Ministry of Science and Innovation, and also by
the National Research Program Oriented to the Challenges of Society (Project PID2020-112875RBC21,
MCIN/AEI /10.13039/501100011033), also this publication is part of the PRE2021-097925
support (funded by MCIN/AEI/10.13039/501100011033 and by the FSE+), and the University of
Huelva/CBUA.Departamento de Ingeniería Química, Química Física y Ciencias de los Materiale
Analysis of the high-frequency content in human qrs complexes by the continuous wavelet transform: An automatized analysis for the prediction of sudden cardiac death
Background: Fragmentation and delayed potentials in the QRS signal of patients have been postulated as risk markers for Sudden Cardiac Death (SCD). The analysis of the high-frequency spectral content may be useful for quantification. Methods: Forty-two consecutive patients with prior history of SCD or malignant arrhythmias (patients) where compared with 120 healthy individuals (controls). The QRS complexes were extracted with a modified Pan-Tompkins algorithm and processed with the Continuous Wavelet Transform to analyze the high-frequency content (85–130 Hz). Results: Overall, the power of the high-frequency content was higher in patients compared with controls (170.9 vs. 47.3 103nV2Hz−1; p = 0.007), with a prolonged time to reach the maximal power (68.9 vs. 64.8 ms; p = 0.002). An analysis of the signal intensity (instantaneous average of cumulative power), revealed a distinct function between patients and controls. The total intensity was higher in patients compared with controls (137.1 vs. 39 103nV2Hz−1s−1; p = 0.001) and the time to reach the maximal intensity was also prolonged (88.7 vs. 82.1 ms; p < 0.001). Discussion: The high-frequency content of the QRS complexes was distinct between patients at risk of SCD and healthy controls. The wavelet transform is an efficient tool for spectral analysis of the QRS complexes that may contribute to stratification of risk
Evaluación de distintos métodos de predicción de rachas de viento
Ponencia presentada en: XXIX Jornadas Científicas de la AME y el VII Encuentro Hispano Luso de Meteorología celebrado en Pamplona, del 24 al 26 de abril de 2006
Control de la expansión isotérmica para conversión de calor a trabajo mecánico
[Resumen]
A consecuencia de recientes avances en las técnicas de conversión de energía térmica a trabajo mecánico basadas en procesos de expansión isotérmica, surge la necesidad de controlar la temperatura de los procesos de expansión. Dado que la velocidad de las máquinas térmicas tiene que ser alta para favorecer tanto la eficiencia térmica como el trabajo específico, se hace imprescindible la aplicación de técnicas de control dotadas de alta velocidad de muestreo. Este artículo aborda el estudio preliminar encaminado a la implementación de máquinas de expansión isotérmica en base a la utilización de algoritmos de control de temperatura durante la expansión isotérmica. Se proponen estructuras algorítmicas de control susceptibles de aplicación utilizando tanto medidas directas como indirectas de medición por conversión de las señales para obtener resultados técnica y económicamente viables
Relationship between predicted speed reduction on horizontal curves and safety on two-lane rural roads in Spain
According to different studies, speed reduction is considered one of the major factors in contributing road safety. For that reason, several guidelines have been recommended for maximum desirable speed reductions from tangents to horizontal curves and for maximum differentials between design and operating speeds on horizontal curves. The Interactive Highway Safety Design Model (IHSDM) Design Consistency Module presents an analysis of the relationship between speed reduction and crashes for horizontal curves on U.S. two-lane rural highways. This paper presents the relationship between speed reduction and crashes for horizontal curves on Spanish two-lane rural roads. A model for using regression analysis to predict crashes is presented. Exposure, curve length (CL), and difference in 85th-percentile speeds (δV85) between successive tangents and horizontal curves, as well as between successive curves, are used. The model's coefficients were different from the ones obtained for U.S. highways, although the values of the goodness-of-fit criteria were similar. In addition, the relationship between crashes and different speeds is analyzed, taking the difference in speed as a speed differential not exceeded by 85% of the drivers traveling under free-flow conditions (δ85V), instead of considering it as δV85. The two models (δV85 versus δ85V) give very similar results
Psychometric Properties of the Spanish Version of the Flow State Scale
The purpose of this research was to examine the psychometric properties of a Spanish translation of the Flow State Scale (FSS; Jackson & Marsh, 1996). This instrument is used to assess the Flow State in participants of physical activity, although it can be adapted to other contexts (such as work, educational contexts, etc.). This construct can be considered the optimal psychological state to carry out an activity, being closely related to motivation and personal enjoyment (Csikszentmihalyi, 1997). A sample of 2036 athletes was recruited from diverse sports activities. The results revealed satisfactory validity and internal consistency of the instrument, obtaining a factor model made up of a main factor and nine subscales. The correlations between motivational orientations and the flow state are highlighted. The Spanish translation of this instrument is found to be acceptable, with similar psychometric properties as the original scale, although future research in other contexts is needed to support these outcomes.El objetivo de esta investigación fue analizar las propiedades psicométricas de una versión adaptada al castellano de la Flow State Scale (FSS; Jackson y Marsh, 1996), instrumento utilizado para valorar el estado de fluidez en practicantes de actividad física, aunque adaptable a otros contextos (trabajo, educación…). Dicho constructo puede ser considerado como el estado psicológico óptimo para realizar una actividad, estando muy relacionado con la motivación y el disfrute personal (Csikszentmihalyi, 1997). Se desarrolló un estudio con 2036 participantes en diferentes actividades deportivas. Los resultados han demostrado que el instrumento posee una validez y consistencia interna aceptables, hallándose un modelo factorial compuesto por un factor principal y nueve factores secundarios. Asimismo, destacan las correlaciones entre las dos orientaciones motivacionales y el estado de fluidez. Se concluye que la adaptación al castellano del instrumento para valorar el estado de fluidez es aceptable, encontrándose propiedades psicométricas similares a las obtenidas en la escala original, aunque se necesitan nuevos trabajos en otros contextos que apoyen estos resultados
Efectos sobre la accesibilidad de la red de autovías planeada en el Plan de Infraestructuras para la Sostenibilidad del Transporte en Andalucía (España)
En este artículo se analizan los impactos en la accesibilidad territorial en Andalucía de las actuaciones
en carreteras planificadas por la Consejería de Fomento y Vivienda de la Junta de Andalucía.
Para ello, se ha desarrollado una herramienta informática basada en Sistemas de Información
Geográfica, y se han calculado una serie de indicadores de accesibilidad y cohesión territorial.
Para llevar a cabo el análisis de los efectos del Plan de Infraestructuras para la Sostenibilidad del
Transporte en Andalucía, se han contemplado dos escenarios: uno sin las actuaciones previstas y
otro con todas las actuaciones planeadas implementadas. También se han estudiado los efectos de
dicho plan sobre la accesibilidad a hospitales, universidades y centros logísticos, así como las mejoras
inducidas por cuatro importantes actuaciones concretas. Los resultados muestran mejoras
significativas, como una reducción media en los tiempos de viaje del 3,6%, y que las actuaciones
del plan de infraestructuras potencian la cohesión territorial.The present study aims to analyze the territorial impacts in Andalusia (through changes in accessibility)
derived from the improvements in the road network planned by the Ministry of Development
and Housing of the Junta de Andalusia. For this purpose, a computer tool based on
Geographic Information Systems was developed, and a series of accessibility and territorial cohesion
indicators were calculated. To carry out the analysis of the effects of the Infrastructure Plan
for the Sustainability of Transport in Andalusia, two scenarios were considered (with and without
the planned actions). The effects of this plan on accessibility to hospitals, universities and logistics
centers, as well as the improvements induced by four strategic actions, were studied as well. The results show the effects of the actions of this plan of infrastructures: an average reduction of the
travel times of 3.6%, and an improvement of the territorial cohesion.Este estudio ha sido realizado en el marco de los PROYECTOS DE I+D+i 2014-2015 (Código del
Proyecto: GGI3003IDID), y financiado por la Consejería de Fomento y Vivienda de la Junta de
Andalucía mediante fondos de la UE y de la Junta de Andalucía
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