Embargo
Photoisomerization-induced LMR shift for UV radiation detection
(Elsevier, 2024) Gallego Martínez, Elieser Ernesto; Ruiz Zamarreño, Carlos; Matías Maestro, Ignacio; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
This work presents an optical sensor for ultraviolet radiation (UV) detection, based on the combined effects of Lossy Mode Resonance (LMR) in the mid infrared (MIR) spectral region and the photoisomerization of a polymeric dye coating. LMR was obtained by means of a sputtered SnO2 thin film on a tetrafluoroethylene-perfluoro (or alkoxy Vinyl Ether, PFA) substrate, along with a photo sensitive coating based on poly R-478. Obtained devices shown response and recovery times of 12 and 43 s, respectively, for an UV excitation of 71 mW at 365 nm. Sensitivity as a function of the excitation wavelength was studied with the highest value of 26 nm/mW obtained at 280 nm. For this excitation wavelength, the limit of detection (LoD) obtained was 0.024 mW. Four different excitation wavelengths were used to cover all UV regions (280, 310, 365 and 395 nm). All measurements were performed at room temperature and humidity (25 ¿C ± 1 ¿C and 13% R.H. ± 2% R.H. respectively). As far as we know, it is the first time that the LMR effect has been recognized in combination with a photoisomerization process.
Open Access
Methodology to assess the impact of the introduction of new technologies in smart cities
(Federación de Asociaciones de Ingenieros Industriales de España, 2015) Branchi, Pablo Emilio; Fernández Valdivielso, Carlos; Matías Maestro, Ignacio; Institute of Smart Cities - ISC
Estamos frente a una revolución producto de los sistemas digitales y de comunicación, donde el papel de la tecnología continuará creciendo exponencialmente. Está calando profundamente en la sociedad, y tiene un alto impacto en las infraestructuras, los sistemas de transporte, en los edificios y en el espacio público. En el ámbito urbano se reconfigura el escenario tradicional tecnológico, con sistemas que generan nuevas necesidades, descubriendo nuevas realidades que buscan nuevas soluciones. El objetivo de este trabajo es el de establecer una metodología para la elaboración de una herramienta de evaluación para las diferentes tecnologías en función de su utilidad y consecuencias, contemplando la incidencia de sus aplicaciones. Con ella se podrán evaluar, por parte de políticos y técnicos prescriptores, las ventajas y desventajas de cada iniciativa, las virtudes de las tecnologías y sistemas disponibles, y el modo óptimo de su aplicación en las Ciudades Inteligentes.
Open Access
Surface exciton polariton resonances (SEPR)-based sensors
(Elsevier, 2023) Vitoria Pascual, Ignacio; Ruiz Zamarreño, Carlos; Ozcariz Celaya, Aritz; Imas González, José Javier; Del Villar, Ignacio; Matías Maestro, Ignacio; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
A new type of resonance in the development of sensors using long-range surface exciton polariton (LRSEP) phenomena has been coined: surface exciton plasmon resonance (SEPR). The resonance was obtained in the reflected spectrum of a Kretschmann-Raether setup with a two-coupled-interface structure composed of 412 nm magnesium fluoride and 50 nm chromium thin films. The roles of different parameters such as thicknesses of the films and the incidence angles have been simulated. Some preliminary experimental results show a promising performance with a shift of the resonance central wavelength with changes in the incidence angle of -136.52 nm/° and a sensitivity of 23,221 nm/refractive index unit.
Open Access
Smart charging station with photovoltaic and energy storage for supplying electric buses
(IEEE, 2022) Berrueta Irigoyen, Alberto; Astrain Escola, José Javier; Puy Pérez de Laborda, Guillermo; El Hamzaoui, Ismail; Ursúa Rubio, Alfredo; Sanchis Gúrpide, Pablo; Villadangos Alonso, Jesús; Falcone Lanas, Francisco; López Martín, Antonio; Matías Maestro, Ignacio; Institute of Smart Cities - ISC
A Smart Charging Station (SCS) has been installed in the Public University of Navarre, Spain, in the framework of the H2020 Smart City Lighthouse STARDUST project. The SCS consists of a high-power electric bus charging point (300 kW), a 100 kW photovoltaic system, a 84 kWh support energy storage system based on a second-life lithiumion battery, and a monitoring and control system that allows the safe storage and convenient access to operation data. This SCS operates as a Smart Grid, being able to provide the power peaks required by the electric bus charger, reducing and smoothing the power demanded from the distribution grid and increasing the renewable energy self-consumption rate. This contribution presents a novel monitoring and control system, which is a key tool to integrate this SCS in the data infrastructure of a Smart City, as well as an energy management system able to operate the SCS to achieve the above-mentioned technical requirements. The crucial role of the monitoring and control system and the energy management system becomes evident in this work.
Open Access
Fault detection of planetary gears based on signal space constellations
(MDPI, 2022) Martincorena Arraiza, Maite; Cruz Blas, Carlos Aristóteles de la; López Martín, Antonio; Molina Vicuña, Cristian; Matías Maestro, Ignacio; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación
A new method to process the vibration signal acquired by an accelerometer placed in a planetary gearbox housing is proposed, which is useful to detect potential faults. The method is based on the phenomenological model and consists of the projection of the healthy vibration signals onto an orthonormal basis. Low pass components representation and Gram–Schmidt’s method are conveniently used to obtain such a basis. Thus, the measured signals can be represented by a set of scalars that provide information on the gear state. If these scalars are within a predefined range, then the gear can be diagnosed as correct; in the opposite case, it will require further evaluation. The method is validated using measured vibration signals obtained from a laboratory test bench.
Open Access
Distributed opportunistic wireless mapping system towards smart city service provision
(IEEE, 2021) Villadangos Alonso, Jesús; Falcone Lanas, Francisco; López Martín, Antonio; Astrain Escola, José Javier; Sanchis Gúrpide, Pablo; Matías Maestro, Ignacio; Estatistika, Informatika eta Matematika; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Estadística, Informática y Matemáticas; Ingeniería Eléctrica, Electrónica y de Comunicación
The knowledge of wireless signal distribution within an urban scenario can provide useful information to users as well as to enhance connectivity and device operation or to perform municipal logistics based on crowd density and user mobility patterns. In this work, a distributed wireless mapping system, based on a combination of opportunistic nodes such as smartphones which map geolocated WiFi access point connection and received power levels, and a cloud-based information gathering architecture is described. The proposed system has been tested in the framework of the Smart City platform of the city of Pamplona, providing signal distribution heat maps, which can be used for multiple municipal services.
Open Access
Ammonia gas optical sensor based on lossy mode resonances
(IEEE, 2023) Armas, Dayron; Zubiate Orzanco, Pablo; Ruiz Zamarreño, Carlos; Matías Maestro, Ignacio; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
This letter presents the fabrication and characterization of an ammonia (NH 3) gas optical sensor based on lossy mode resonances (LMRs). A chromium (III) oxide (Cr 2 O 3) thin film deposited onto a planar waveguide was used as LMR supporting coating. The obtained LMR shows a maximum attenuation wavelength or resonance wavelength centered at 673 nm. The optical properties of the coating can be modified as a function of the presence and concentration of NH 3 in the external medium. Consequently, the refractive index of the Cr 2 O 3 thin film will change, producing a red-shift of the resonance wavelength. Obtained devices were tested for different concentrations of NH 3 as well as repetitive cycles. Concentrations as low as 10 ppbv of NH 3 were detected at room temperature. Machine learning regression models were used to mitigate the cross-sensitivity of the device under temperature and humidity fluctuations.
Open Access
An antibacterial surface coating composed of PAH/SiO2 nanostructurated films by layer by layer
(Wiley, 2010) Urrutia Azcona, Aitor; Rivero Fuente, Pedro J.; Ruete Ibarrola, Leyre; Goicoechea Fernández, Javier; Fernández Valdivielso, Carlos; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería; Ingeniaritza; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC
In this work we propose a novel antibacterial coating composed of SiO2 and the polymer Poly(allylamine hydrochloride) (PAH). The coating was fabricated by the technique Layer-by-Layer (LbL). This technique has already been used in previous works, and it has the advantage that it allows to control the construction of nanosized and well organized multilayer films. Here, the new nanotexturized LbL SiO2 surface acts as antibacterial agent. The fabricated coatings have been tested in bacterial cultures of genus Lactobacillus to observe their antibacterial properties. It has been demonstrated these PAH/SiO2 coating films have a very good antimicrobial behaviour against this type of bacteria.
Open Access
Mode transition during deposition of nanoscale ITO coatings on tilted fiber Bragg gratings
(Optica Publishing Group, 2022) Imas González, José Javier; Albert, Jacques; Del Villar, Ignacio; Ozcariz Celaya, Aritz; Ruiz Zamarreño, Carlos; Matías Maestro, Ignacio; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
The mode transition phenomenon is experimentally demonstrated in tilted fiber Bragg gratings (TFBG) through the deposition of an indium tin oxide (ITO) thin film employing a DC sputtering machine.
Open Access
Femtomolar detection by nanocoated fiber label-free biosensors
(American Chemical Society, 2018) Chiavaioli, Francesco; Zubiate Orzanco, Pablo; Del Villar, Ignacio; Ruiz Zamarreño, Carlos; Giannetti, Ambra; Tombelli, Sara; Trono, Cosimo; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Baldini, Francesco; Institute of Smart Cities - ISC; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
The advent of optical fibre-based biosensors combined with that of nanotechnologies has provided an oppor-tunity for developing in situ, portable, lightweight, versatile and high-performance optical sensing platforms. We report on the generation of lossy mode resonances by the deposition of nm-thick metal oxide films on optical fibres, which makes it possible to measure precisely and accurately the changes in optical properties of the fibre-surrounding medium with very high sensitivity compared to other technology platforms, such as long period gratings or surface plasmon resonances, the gold standard in label-free and real-time biomolecular interaction analysis. This property, combined with the application of specialty structures such as D-shaped fibres, permits enhancing the light-matter interaction. SEM and TEM imaging together with X-EDS tool have been utilised to characterise the two films used, i.e. indium tin oxide and tin dioxide. More-over, the experimental transmission spectra obtained after the deposition of the nanocoatings have been numerically cor-roborated by means of wave propagation methods. With the use of a conventional wavelength interrogation system and ad-hoc developed microfluidics, the shift of the lossy mode resonance can be reliably recorded in response to very low analyte concentrations. Repeated experiments confirm a big leap in performance thanks to the capability to detect femtomolar concentrations in human serum, improving the detection limit by three orders of magnitude when compared with other fibre-based configurations. The biosensor has been regenerated several times by injecting sodium dodecyl sul-phate, which proves the capability of sensor to be reused.