Resultados de investigación

[ES] Este dataset recopila y estructura 100 bulos y contenidos desinformativos de gran impacto difundidos en torno a la DANA de Valencia de 2024. Cada registro corresponde a un bulo individual e incluye, cuando está disponible, identificador único, descripción del contenido, fecha de primera aparición, plataforma de difusión, alcance estimado, clasificación temática y referencias a la verificación (organización verificadora y URL). El conjunto de datos se ha construido a partir de enlaces de verificación y del proceso de codificación del estudio asociado, manteniendo valores ausentes como datos faltantes para no introducir supuestos. El objetivo es facilitar análisis reproducibles en comunicación, ciencias sociales y estudios de desinformación sobre dinámicas de viralidad, narrativas y respuesta institucional en contextos de crisis y catástrofes naturales., [EN] This dataset compiles and structures 100 high-impact hoaxes and misleading contents circulated around the 2024 Valencia DANA. Each record corresponds to one item and includes, when available, a unique identifier, content description, first-seen date, distribution platform, estimated reach, thematic classification, and fact-checking references (verifier and URL). The dataset was built from fact-check links and the coding process of the associated study, preserving missing values as missing data to avoid introducing assumptions. It supports reproducible research in communication, social sciences, and misinformation studies on virality, narratives, and institutional response in crisis and natural-disaster contexts.

[EN] We propose and experimentally demonstrate the use of a directly modulated laser (DML) in an optical phase modulated (PM)-assisted millimeter-wave (mmW) signal generation system. A comprehensive analytical model is provided to accurately describe the system frequency response, which is also validated by the experimental measurements. For the purpose of the system characterization, the transmission performance is analyzed using a QPSK signal at different operating mmW frequencies over large received optical power (RoP) and electrical data power ranges in a 10 km standard single mode fiber (SSMF) link. Both the impact of the noise and the DML nonlinearities lead to identify the optimal conditions for the system operation where PM-based mmW signal photonic generation demonstrates total transparency with no further signal degradation. Final comparison with IM technique for mmW signal generation leads to assess the robustness of PM solution which makes it promising for the deployment of future communication networks.

Datasets of English and Spanish tweets used in the project "ALLEGRO: Smart multi-modal crowdsensing-based system as a service oriented to the prediction of social problems". Tweets in each dataset were manually tagged according to a specific social problem: Black Economy, Institutional Elder Abuse, Student Dropout, and Violence Against Women., Este database es parte del proyecto de I+D+i PID2020-112827GB-I00 financiado por MICIU/AEI/10.13039/501100011033.

[EN] This work experimentally demonstrates the convergence of visible light communications (VLC) and millimeter wave (mmW) wireless access technologies by using a unified optical fronthaul link that provides simultaneous signals to be transmitted over light emitting diode (LED) and seamless antennas-based links, respectively. Frequency multiplication is provided in the fiber link by using a carrier suppressed Mach-Zehnder modulator (CS-MZM) that offers a high-quality signal generation at both baseband (BB) and mmW frequencies. Moreover, this flexible and efficient photonic signal generation approach uses a directly modulated laser (DML) to take advantage of the relative gain given by the combination of the DML chirp and the fiber dispersion in the mmW band. Experimental trials of simultaneous VLC and mmW access have been done over distances up to 2.5 and 4 m, respectively; with maximum throughputs of around 70.3 and 393.1 Mbps for signal bandwidths of 30 and 100 MHz, respectively. Moreover, the effective transmission of different M-QAM OFDM modulation formats validates the approach as a promising enabler for future convergent heterogeneous 6G networks.

[EN] A comprehensive dataset of pollen images has been constructed. This Ground Truth termed POLLEN24_SP, comprised 32.285 pollen/particle images (captured by an expert using optical microscopy) and covers the 24 most prevalent types of pollen grains found in Spanish honeys. Twelve different pre-existing Convolutional Neural Networks (CNN) were evaluated in order to discern the relative frequencies of different pollen types, including our new proposals PolleNetV2 and PollenNetV2.mobile., This research was funded by the Next Generation European Union and the Plan de Recuperación, Transformación y Resiliencia of the Spanish Government, with the support of Generalitat Valenciana (project AGROALNEXT/2022/043)

[ES] Esquemático del sistema de multiplicación de frequencia óptica en el que los datos han sido subidos a radiofrequency mediante un mezclador. Espectros eléctricos y óptico, caracterización del sistema en terminos de la magnitud del vector de error frente a potencia óptica recibida y potencia eléctrica recibida. Caracterización del sistema en términos de magnitud del vector de error frente a los distintos anchos de banda admitidos para señales OFDM y portadora única.

[ES] We demonstrate a convergent optical fronthaul link for enabling heterogeneous wireless access technologies in 6G future networks deployment based on a directly modulated laser and an external Mach–Zehnder modulator biased at null point for optical frequency multiplying. Simultaneous transmission of two M-QAM data signals over baseband and millimeter wave (mmW) frequency band, i.e. 42 GHz, is demonstrated over a 10 km fiber link, showing the suitability for visible light communications and mmW radio access, respectively, to the final user. System intermodulation in mmW band is identified under high received optical power levels and overcome by inserting a dispersion compensation module.

[EN] The dataset is composed of 36 variables (columns) and 215 nmber of cases (rows): The raw matrix consists in 215 honeys x 34 spectral regions=7310 scores. A total of 215 Spanish honey samples from different botanical origins were used in this study. The melissopalynological analysis was carried out by an expert technician who then classified each honey sample as either monofloral or polyfloral. This analysis took placed in the Honey Laboratory of the Universitat Politècnica de València” (LABMIEL) (accredited in pollen analysis by ISO 1702) (ISO/IEC 17025:2017, 2017). The criteria of minimum type of pollen that were considered by this laboratory to classify a honey as monofloral is: citrus honey (10% Citrus sp pollen); rosemary honey (10% Rosmarinus officinalis pollen); thyme honey (10% Thymus sp.); lavender honey (10% Lavandula stoechas); heather honey (45% Erica sp.) and eucalyptus honey (70% Eucalyptus sp.). The FTIR spectra of all the honey samples were recorded, focusing on the spectral differences in the regions between 3672 and 753 cm⁻¹ (resolution of 2 cm-1; average of 32 scans and room temperature). Thirty-four A total of 215 Spanish honey samples from different botanical origins were used in this study. The melissopalynological analysis was carried out by an expert technician who then classified each honey sample as either monofloral or polyfloral. This analysis took placed in the Honey Laboratory of the Universitat Politècnica de València” (LABMIEL) (accredited in pollen analysis by ISO 1702) (ISO/IEC 17025:2017, 2017). The criteria of minimum type of pollen that were considered by this laboratory to classify a honey as monofloral is: citrus honey (10% Citrus sp pollen); rosemary honey (10% Rosmarinus officinalis pollen); thyme honey (10% Thymus sp.); lavender honey (10% Lavandula stoechas); heather honey (45% Erica sp.) and eucalyptus honey (70% Eucalyptus sp.). The FTIR spectra of all the honey samples were recorded, focusing on the spectral differences in the regions between 3672 and 753 cm⁻¹ (resolution of 2 cm-1; average of 32 scans and room temperature). Thirty-four spectral regions corresponding to peaks or shoulders, related to structural or functional group information were obtained for each sample. Therefore the raw matrix consists in 215 honeys x 34 variables. corresponding to peaks or shoulders, related to structural or functional group information were obtained for each sample. Therefore the raw matrix consists in 215 honeys x 34 A total of 215 Spanish honey samples from different botanical origins were used in this study. The melissopalynological analysis was carried out by an expert technician who then classified each honey sample as either monofloral or polyfloral. This analysis took placed in the Honey Laboratory of the Universitat Politècnica de València” (LABMIEL) (accredited in pollen analysis by ISO 1702) (ISO/IEC 17025:2017, 2017). The criteria of minimum type of pollen that were considered by this laboratory to classify a honey as monofloral is: citrus honey (10% Citrus sp pollen); rosemary honey (10% Rosmarinus officinalis pollen); thyme honey (10% Thymus sp.); lavender honey (10% Lavandula stoechas); heather honey (45% Erica sp.) and eucalyptus honey (70% Eucalyptus sp.). The FTIR spectra of all the honey samples were recorded, focusing on the spectral differences in the regions between 3672 and 753 cm⁻¹ (resolution of 2 cm-1; average of 32 scans and room temperature). Thirty-four spectral regions corresponding to peaks or shoulders, related to structural or functional group information were obtained for each sample. The raw matrix consists in 215 honeys x 34 spectral regions=7310 variables

[EN] We experimentally demonstrate a photonic full-duplex seamless millimeter wave fronthaul link, based on phase modulation, to address the challenges arising from the increased demands on the mobile fronthaul capacity and network densification toward 5G and beyond. The proposed system relies on phase modulation techniques, implemented at both the central office (CO) and remote radio head (RRH), to achieve optical frequency upconversion of the downlink (DL) signal and optical modulation of the down-converted uplink (UL) signal. Furthermore, our approach includes the frequency down-conversion of the 40 GHz UL signal through an optically generated local oscillator (LO) signal in the RRH, while the laser employed for UL data transmission is situated at the CO, simplifying the remote site’s equipment. An optical waveshaper serves here as a programmable optical filter to provide signals for DL frequency up-conversion, LO generation, and also the optical carrier for UL transmission. In our experimental validation, we have tested our proposed system using 64-quadrature amplitude modulation (64-QAM) for the DL at a frequency of 41 GHz and quadrature phase shift keying (QPSK) for the UL at a frequency of 40 GHz. Notably, our results demonstrate the successful transmission of up to 200 MHz bandwidth for both digital modulation schemes, all while maintaining the error vector magnitude (EVM) well below the specified threshold. Additionally, when employing 5G new radio (NR) orthogonal frequency-division multiplexing (OFDM) signals with the same modulation formats for both links in full-duplex communication, we achieved EVM values as low as 5.2% for the DL and 6.9% for the UL, further highlighting the efficacy and robustness of our proposed solution.

[EN] LED lighting has become the standard solution for illumination purposes thanks to its energy efficiency. Nowadays, there is growing interest in the use of LEDs for data transmission to develop future-generation communication systems. The low cost and widespread deployment of phosphor-based white LEDs make them the best candidate for visible light communications (VLC), although they have a limited modulation bandwidth. This paper presents a simulation model of a VLC link based on phosphor-based white LEDs and a method to characterize the VLC setup used to perform the data transmission experiments. Specifically, the simulation model incorporates the frequency response of the LED, the noise levels coming from the lighting source and the acquisition electronics, and the attenuation due to both the propagation channel and the angular misalignment between the lighting source and the photoreceiver. In order to validate the suitability of the model for VLC, carrierless amplitude phase (CAP) and orthogonal frequency division multiplexing (OFDM) modulation signals were employed for data transmission, and simulations with the proposed model and measurements over the equivalent scenario show high agreement.