Search

Durante los dos últimos cursos, la educación universitaria se ha visto obligada a cambiar de forma precipitada debido a la pandemia mundial que nos ha afectado. A pesar de los esfuerzos de las instituciones por adaptarse de una forma adecuada a un modelo semi-presencial o virtual a lo largo del curso, la percepción de los estudiantes no siempre corresponde con la que se pretende desde los organismos oficiales. En este estudio se ha realizado una encuesta voluntaria al alumnado de diferentes titulaciones de grado y másteres del área de ingeniería con el objetivo de someter a examen las medidas adoptadas por la Universidad de Granada (UGR) y comprobar si son aceptadas por los estudiantes y si, desde su punto de vista, se podrían mantener a largo plazo.

Several studies have shown that the determination of pH in sweat, which is one of the most accessible body fluids, can be an indicator of health and wellness, and even be used for potential disease diagnosis. On that basis, we present herein a wearable wristband for continuous and wireless monitoring of sweat pH with potential applications in the field of personal health assessment. The developed wristband consists of two main parts: a microfluidic cloth analytical device (μCAD) to collect continuously the sweat from skin with a color-based pH sensing area; and a readout and processing module with a digital color sensor to obtain the pH of sweat from the color changes in the μCAD. In addition, the readout module includes a low-power Bluetooth interface to transmit the measurements in real-time to a custom-designed smartphone application. To allow continuous operation, an absorbent pad was included in the design to retire and store thsweat from the sensing area through a passive pump path. It was found that the Hue parameter (H) in the HSV color space can be related to the sweat pH and fitted to a Boltzmann equation (R2 = 0.997). The range of use of the wristband device goes from 6 to 8, which includes the pH range of sweat, with a precision at different pH values from 3.6 to 6.0 %. Considering the typical human sweat rate, the absorbent pad allows continuous operation up to more than 1000 min.

In this paper we present the design, fabrication and characterization of electro-textile inductor and capacitor patterns on denim fabric as a basis for the development of wearable e-textiles. Planar coil inductors have been harnessed as antenna structures for the development of Near Field Communication (NFC) tags with temperature sensing capability, while interdigitated electrode (IDE) capacitors have been used as humidity sensors for wearable applications. The effect of bending in the electrical performance of such structures was evaluated, showing variations below 5% in both inductance and capacitance values for bending angles in the range of interest, i.e. those fitting to human limbs. In the case of the fabricated NFC tags, a shift in the resonance frequency below 1.7% was found, meaning that the e-textile tag would still be readable by an NFC enabled smartphone. In respect of the capacitive humidity sensor, we obtained a minimum capacitance variation of 40% for a relative humidity range from 10% to 90%. Measured thermal shift was below 5% in the range from 10 to 40ºC. When compared to the 4% variation due to bending, it can be concluded that this capacitive structure can be harnessed as humidity sensor even under bending strain conditions and moderate temperature variations. The development and characterization of such structures on denim fabrics, which is one of the most popular fabrics for everyday clothing, combined with the additional advantage of affordable and easy fabrication methodologies, means a further step towards the next generation of smart e-textile products., This study was supported by projects from the Spanish government (CTQ2016-78754- C2-1-R and EQC2018-004937-P). These projects were partially supported by European Regional Development Funds (ERDF). P. Escobedo wants to thank to the Spanish Ministry of Education, Culture and Sport for a R&D predoctoral grant (FPU13/05032).

In this work we present a novel technique to estimate the resonance frequency of LC chipless tags (inductor-capacitor parallel circuit) with improved sensitivity and linearity. The developed reader measures the power consumption of a Colpitts oscillator during a frequency sweep. The readout circuit consists of a Colpitts oscillator with a coil antenna, varactor diodes to change the oscillator frequency, analog circuitry to measure the power consumption and a microcontroller to control the whole system and send the data to a PC via USB. When an LC tag is inductively coupled to the oscillator, without contact, a maximum power peak is found. As shown by an experimental calibration using an LC tag made on FR4 substrate, the frequency of this maximum is related to the resonance frequency. Both parameters, power consumption and resonance frequency, present an excellent linear dependence with a high correlation factor (R2 = 0.995). Finally, a screen-printed LC tag has been fabricated and used as relative humidity sensor achieving a sensitivity of (-2.41 ± 0.21) kHz/% with an R2 of 0.946., This work was supported by projects CTQ2016-78754-C2-1-R and FPA2015-67694-P from the Spanish Ministry of Economics and Competitivity and the European Regional Development Fund (ERDF).; and PI-0505-2017 within the biomedical and health sciences research, development and innovation projects in Andalucía.

Nowadays, it is more and more common to find devices that permits to everybody carry out analysis of different analytes of interest as glucose in blood or creatinine in urine by themselves, thanks to the development of the Point-of-Care (POC) devices. POC’s permit the in situ analysis of the samples, in an easy way, quickly and by the use of a small amount of sample in the sampling area of the device, obtaining result with no need of instrumentation or by the use of a very simple one. In order to match these objectives and make the device useful for everybody in any condition, the WHO has described the ASSURED guidelines for the POC devices[1]. In the recent years, and thanks to the capillary properties of different materials as paper, thread or cloth, the development of the POC devices are turning to a new strategy that implies the inclusion of the POC devices in t-shirts, bracelets or patches obtaining in this way wearables sensors. In this kind of sensor, instead of the addition of the sample in the sampling area, it moves through the device arriving to recognition/transduction area were the property of the sensor changes and can be measured and related to the concentration of the analyte. In this work, we present a wearable POC that permits the real-time determination of the pH in sweat. For this purpose, we have developed a μCAD (Figure) that contains a pH indicator (4-[4-(2-hydroxyethanesulfonyl)-phenylazo]-2,6-dimethoxyphenol (GJM-534) [2]) covalently immobilized on cotton cloth, which color is going to change from yellow (pH around 6) to pink (pH around 9) depending on the pH. The size and shape of the μCAD (see Figure) was designed taking into account the low flow rate of sweat generated in the wrist when sweating (0.01 μL/min) including a superabsorbent material working as passive pump to avoid the saturation of sample of the μCAD. The colorimetric device was calibrated using the H parameter from the HSV color space as analytical parameter, obtaining the calibration function and analytical parameters of the device, the reversibility of the μCAD, response time and stability. Finally, the μCAD was integrated into a bracelet that includes a color detector and a microprocessor that registered the color of the μCAD in real-time and send the information via Bluetooth to a smartphone, obtaining and registering the pH of the sweat while doing exercise., This study was supported by project from the Spanish MINECO (CTQ2016-78754-C2-1-R).

In this paper, we present a passive tag for the determination of gaseous oxygen in intelligent packaging (IP). The power supply for this tag is obtained from thermoelectric energy harvesting taking advantage of the temperature difference between a cooled package and the human body. For this purpose, a compact Peltier module is attached to the surface of the pack7 age. This device is able to generate 1.2 mW when a temperature difference of 25 °C is applied between its surfaces. A dc-to-dc boost converter is included to generate an output voltage of 3.3 V and an output current of 225 µA from the harvested energy by the Peltier cell, which are used to supply the measurement circuitry. A luminescent membrane sensitive to oxygen is used as a gas detector in the package. The generated signal is compared to a reference value to evaluate if the oxygen concentration inside the package falls below or above a predetermined value. This is shown by turning on a green or a red LED, respectively. The proposed system presents a resolution of 0.02% of the predicted oxygen concentration in the range of interest (0%–5%) and a limit of detection (LOD) of 0.007%, which makes the instrument appropriate to be used in IP and active packaging (AP) technology., This work was supported in part by the Spanish Ministry of Economics and Competivity under Project CTQ2016-78754-C2-1-R and in part by the Unidad de Excelencia de Química aplicada a biomedicina y medioambiente, University of Granada. The work of P. E. Araque was supported by the Spanish Ministry of Education, Culture and Sport (MECD) under Grant FPU13/05032. The work of I. M. P. de Vargas-Sansalvador was supported by the European Unions Horizon 2020 research and innovation program under Grant 706303 (MultiSens)

Tesis Univ. Granada. Departamento de Electrónica y Tecnología de Computadores. Leída el 27 de noviembre de 2009

In this work we present a full-passive flexible multigas sensing tag for the determination of oxygen, carbon dioxide, ammonia, and relative humidity readable by a smartphone. This tag is based on near field communication (NFC) technology for energy harvesting and data transmission to a smartphone. The gas sensors show an optic response that is read through high-resolution digital color detectors. A white LED is used as the common optical excitation source for all the sensors. Only a reduced electronics with very low power consumption is required for the reading of the optical responses and data transmission to a remote user. An application for the Android operating system has been developed for the power supplying and data reception from the tag. The responses of the sensors have been calibrated and fitted to simple functions, allowing a fast prediction of the gases concentration. Cross-sensitivity has also been evaluated, finding that in most of the cases it is negligible or easily correctable using the rest of the readings. The election of the target gases has been due to their importance in the monitoring of modified atmosphere packaging. The resolutions and limits of detection measured are suitable for such kinds of applications., This work was supported by project CTQ2013-44545-R from the Ministry of Economy and Competitiveness (Spain) and Junta de Andalucía (Proyecto de Excelencia P10- FQM-5974). These projects were partially supported by European Regional Development Funds (ERDF). P. Escobedo wants to thank the Spanish Ministry of Education, Culture and Sport (MECD) for a pre-doctoral grant (FPU13/05032).

This work presents the design, fabrication, and characterization of a passive printed radiofrequency identification tag in the ultra-high-frequency band with multiple optical sensing capabilities. This tag includes five photodiodes to cover a wide spectral range from near-infrared to visible and ultraviolet spectral regions. The tag antenna and circuit connections have been screen-printed on a flexible polymeric substrate. An ultra-low-power microcontroller-based switch has been included to measure the five magnitudes issuing from the optical sensors, providing a spectral fingerprint of the incident electromagnetic radiation from ultraviolet to infrared, without requiring energy from a battery. The normalization procedure has been designed applying illuminants, and the entire system was tested by measuring cards from a colour chart and sensing fruit ripening.

Número de publicación: ES2335176 B1. Número de solicitud: 200802654., Dicho sistema comprende componentes de instrumentación (hardware), componentes lógicos de programación (software) y un conjunto de elementos de detección formados por un número de fotodetectores colocados en la suela del zapato deportivo. El funcionamiento se basa en el registro de los cambios en las señales de los fotodetectores sobre la base de una referencia temporal común a todos estos últimos., The invention relates to a system for measuring the temporal parameters of walking, running and jumping by means of photodetectors. Said system comprises instrumentation components (hardware), logical programming components (software) and a set of detection elements formed by a number of photodetectors placed on the sole of the sports shoe. Operation is based on recording the changes in the signals from the photodetectors on the basis of a temporal reference common to all of the latter., Universidad de Cádiz, Universidad de Granada

The tracking and monitoring of environmental parameters of significant interest such as temperature, humidity, ionizing radiation and substances or gases concentration is a growing demand in different sectors: from personal and clinic healthcare areas to food safety and industrial fields, including applications in the context of Wireless Sensor Networks (WSNs) and Internet of Things (IoT). Besides, the emergence of Printed Electronics (PE) technology has enabled the development of sensing devices on flexible substrates such as paper, textile or plastic foils. Using printing techniques to fabricate electronic devices promises lower production costs because of the additive nature of the technology and the advantage of large-area processes with reduced infrastructure. Printed devices can benefit from their potential advantages to be flexible, thin, lightweight, conformal, transparent, wearable, easy-to-integrate, cost-effective and environmentally friendly. The development of printed sensor devices that are selective, sensitive, with fast response, low cost, low power consumption and connected by means of wireless technologies such as Radio Frequency Identification (RFID) or Near Field Communication (NFC) is an option of great scientific and technological interest. Additionally, it is highly desirable to be able to obtain the information from the sensor systems using general-purpose devices that are readily available to all. The combination of printing technologies and sensor devices with wireless connectivity leads to the next paradigm of smart products. The aim of the thesis is the design, development, fabrication and evaluation of sensor systems fundamentally based on the use of printing technologies on flexible substrate as the main manufacturing process. Methodological objectives include the study, characterization and validation of the main printing techniques used in the development of PE on flexible substrates: inkjet and screen printing. Post-processing of printed patterns are also addressed as an essential step towards achieving conductive structures after the printing process. The main strategies are: - Inclusion of commercially available sensors in passive architectures capable of energy harvesting and remote sensor data transmission by means of wireless technologies such as RFID or NFC. - Integration of novel printed sensors into passive systems with conditioning stages where sensor information can be accessed using RFID/NFC or other wireless mechanisms. - Design of printed sensor systems in which the monitored magnitude causes a variation in the electrical properties of the system that can be remotely detected. - Development of smartphone-based sensor platforms in which mobile devices with custom-designed applications allow the powering, data communication and processing of the associated passive sensor systems. The magnitudes of interest are temperature, humidity, radiation and concentration of different gases related to modified atmosphere and food preservation. The outcomes of this work will be passive sensor systems in the form of smart RFID/NFC tags or other simple and low-cost sensor platforms with feasibility to be used in fields such as environmental assessment, healthcare monitoring and smart packaging applications.

Tesis Univ. Granada. Programa Oficial de Doctorado en Tecnologías de la Información y la Comunicación, We thank the Spanish Ministry of Education, Culture and Sport (MECD) for a pre-doctoral grant (FPU13/05032). We would also like to thank the Spanish government for funding under project CTQ2013-44545-R. This project was partially supported by European Regional Development Funds (ERDF), Junta de Andalucía (Proyecto de Excelencia P10-FQM-5974), Talentia Postdoc Program launched by the Andalusian Knowledge Agency, co-funded by the European Union’s Seventh Framework Program, Marie Skłodowska-Curie actions (COFUND—Grant Agreement n◦267226)

Tesis Univ. Granada. Departamento de Electrónica y Tecnología de Computadores