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Metadata-driven universal real-time ocean sound measurement architecture

  • Martínez Padró, Enoc
  • Garcia Benadí, Albert
  • Toma, Daniel
  • Delory, Eric
  • Gomáriz Castro, Spartacus
  • Río Fernandez, Joaquín del
Underwater sound in the oceans has been significantly rising in the past decades due to an increase in human activities, adversely affecting the marine environment. In order to assess and limit the impact of underwater noise, the European Commission’s Marine Strategy Framework Directive (MSFD) included the long-term monitoring of low-frequency underwater sound as a relevant indicator to achieve a good environmental status. There is a wide range of commercial hydrophones and observing platforms able to perform such measurements. However, heterogeneity and lack of standardization in both hydrophones and observing platforms makes the integration and data management tasks time-consuming and error-prone. Moreover, their power and communications constraints need to be addressed to make them suitable for long-term ocean sound monitoring. Measured underwater sound levels are challenging to compare because different measurement methodologies are used, leading to a risk of misunderstandings and data misinterpretation. Furthermore, the exact methodology applied is not always public or accessible, significantly reducing ocean sound data re-usability. Within this work, a universal architecture for ocean sound measurement is presented, addressing hydrophone integration, real-time in situ processing and data management challenges. Emphasis is placed on generic and re-usable components, so it can be seamlessly replicated and deployed in new scenarios regardless of the underlying hardware and software constraints (hydrophone model, observing platform, operating system, etc.). Within the proposed architecture, a generic implementation of an underwater sound algorithm based on underwater noise measurement best practices is provided. Standardized and coherent metadata with emphasis on strong semantics is discussed, providing the building blocks for FAIR (Findable, Accessible, Interoperable, Reusable) ocean sound data management., This work has been funded by the Spanish government project RESBIO (grant agreement TEC2017-87861-R), the EU projects ENVRI-FAIR (grant agreement 824068), the JONAS INTERREG Atlantic Area-funded project (EAPA_52/2018), partly by the Generalitat de Catalunya SARTI-MAR project (grant agreement 2017 SGR 371) and partly by the FPI-UPC_2015 scholarship program., Peer Reviewed

Development of Image processing algorithm for somnolence detection in drivers., Desarrollo de un algortimo para detección de somnolencia a través de procesado de imagen, Desenvolupament d'un algoritme per detectar somnolència mitjançant processament d'imatge

  • Meza García, Brenda
This project consists in the development of image processing algorithms to extract the respiration signal from the image of the chest driver, using several marks placed on the seatbelt., It is proposed a non-invasive method to detect the breathing signal of drivers by marking the seatbelt with some points of reference (stickers) and a camera. It is developed a Matlab code to treat the captured video and extract the trajectory of the stickers by image processing. To evaluate the algorithm, is created a database with help of some volunteers., Se propone un método no invasivo para detectar la señal de respiración de los conductores marcando el cinturón de seguridad con unos puntos de referencia (pegatinas) y una cámara. Se desarrolla un código de Matlab para tratar el vídeo capturado y extraer la trayectoria de las pegatinas con procesado de imagen. Para evaluar el algoritmo, se crea una base de datos con ayuda de unos voluntarios., Es proposa un mètode no invasiu per detectar la senyal de respiració dels conductors marcant el cinturó de seguretat amb uns punts de referència (gomets) i una càmera. Es desenvolupa un codi de Matlab per tractar el vídeo capturat i extreure la trajectòria dels gomets amb processat d’imatge. Per avaluar l’algoritme, es crea una base de dades amb l’ajut d’uns voluntaris.

Test bench of silicon photomultiplier for positron emission tomography application, Banco de pruebas de fotomultiplicadores de silicio para aplicaciones de tomografía por emisión de positrones, Banc de proves dels fotomultiplicadors de silici per a aplicacions de tomografia per emissió de positrons

  • Sanchez Gonzalo, David
Typically the medical imaging devices have been based on scintillator crystals coupled to photomultipliers tubes. But the problems to combine them with high electromagnetic fields and the relatively high cost per unit surface, opens new opportunities on the field for a different type of detector named silicon photomultiplier. These ones offer an alternative solution to combine the high gain of the photomultipliers tubes, and the insensitiveness to the magnetic field, high quantum efficiency and compact structure of the avalanche photodiodes. That allows an increasing quality on the medical imaging technics, such as positron emission tomography, which implies a better and early detection of different diseases. In this study a very promising results for coincidence time resolution and single photon time resolution coming from the silicon photomultiplier combined with a readout electronics developed by SiUB group are shown, where we are trying to reach the limit of the technology., Típicamente la imagen médica estaba basada en utilizar cristales centelleantes acoplados a tubos fotomultiplicadores. Pero los problemas que presentan a la hora de combinarlos con campos electromagnéticos y el relativo alto coste por unidad de área, abre nuevas oportunidades para un tipo diferente de fotodetector, llamados fotomultiplicadores de silicio. Estos combinan la alta ganancia de los tubos fotomultiplicadores y la insensibilidad a los campos electromagnéticos, la alta eficiencia cuántica y la compactación de los fotodiodos de avalancha. Esto permite mejor las técnicas de imagen médica, como pueden ser la tomografía por emisión de positrones, lo que implica una mejor y más rápida detección de diferentes enfermedades. En este estudio encontramos unos prometedores resultados para la resolución temporal en coincidencia y para single photon, proveniente del fotomultiplicador de silicio y leyendo su señal a través de una placa de electrónica desarrollada por el grupo de investigación SiUB, donde estamos llegando al límite de la tecnología., Típicament la imatge medica estava basada en utilitzar cristalls centellejadors acoblats a tubs fotomultiplicadors. Però els problemes que presenten alhora de combinar-los amb camps electromagnètics i el relatiu alt cost per unitat d'àrea, obre noves oportunitats per a un tipus diferent de fotodetector, anomenats fotomultiplicadors de silici. Aquests combinen l'alt guany dels tubs fotomultiplicadors i la insensibilitat als camps electromagnetics, l'alta eficiència quàntica i la compactació dels fotodíodes d'allau. Això permet millor les tècniques d'imatge medica, com poden ser la tomografia per emissió de positrons, el que implica una millor i mes ràpida detecció de diferents infermetats. En aquest estudi trobarem uns prometedors resultats per a la resolució temporal en coincidència i per a single photon, provinent del fotomultiplicador de silici i llegint la seva senyal a través d'una placa d'electrònica desenvolupada pel grup d'investigació SiUB, on estem arribant al límit de la tecnologia.

Analysis of microstructure and strengthening in CuMg alloys deformed by equal channel angular pressing

  • Rodriguez-Calvillo, P.
  • Cabrera Marrero, José M.
The microstructural and strengthening behavior of two CuMg alloys, with 0.2 and 0.5 m.-% of Mg, were analyzed after severe plastic deformation by Equal Channel Angular Pressing (ECAP). Both alloys were passed through a 90° inner angle ECAP die at room temperature up to 16 passes following route Bc. The EBSD analysis of the deformed microstructure revealed a significant grain refinement after the 2nd pass. Average grain sizes as fine as 0.31 and 0.24 µm for the CuMg0.2 and CuMg0.5, respectively, were obtained after 16 passes. The tensile strength of the ECAPed samples of the present CuMg alloys did not reach a saturation level, attaining 570 and 750 MPa after 16 passes for the CuMg0.2 and CuMg0.5, respectively. The dependence of the yield stress on deformation (i.e. number of ECAP passes) and Mg content was evaluated in terms of the Hall–Petch effect (influence of grain size), dislocation density (through the subgrain hardening effect) and solid solution strengthening. Results indicated that the stronger effect comes from the subgrain microstructure rather than from High Angle Grain Boundaries (HAGB). A minor effect of the chemical composition was also noticed.

Hybrid cell centred/vertex model for cellular nanolayers

  • Mosaffa, Payman
  • Asadipour, Nina
  • Millán, Daniel
  • Rodríguez Ferran, Antonio
  • Muñoz Romero, José
Macroscopic deformations in embryonic soft tissues are due to the intra-cellular remodelling and cell intercalation. We here present a computational approach that can handle the two types of deformations, and also take into account the active cell response. The model resorts to cell centred techniques, where particles represent cell nuclei, and to vertex models, where the vertices represent cell boundaries. This hybrid approach allows to consider separately intra-cellular and inter-cellular forces, and at the same time impose cell incompressibility. The model is applied to simulate the active stretching of epithelium., Peer Reviewed

Exploitation of time-of-flight (ToF) cameras

  • Foix Salmerón, Sergi
  • Alenyà Ribas, Guillem
  • Torras, Carme
This technical report reviews the state-of-the art in the field of ToF cameras, their advantages, their limitations, and their present-day applications sometimes in combination with other sensors. Even though ToF cameras provide neither higher resolution nor larger ambiguity-free range compared to other range map estimation systems, advantages such as registered depth and intensity data at a high frame rate, compact design, low weight and reduced power consumption have motivated their use in numerous areas of research. In robotics, these areas range from mobile robot navigation and map building to vision-based human motion capture and gesture recognition, showing particularly a great potential in object modeling and recognition.

The EPNet Project. Production and distribution of food during the Roman Empire: Economics and Political Dynamics

  • Remesal, José
  • Díaz-Guilera, Albert
  • Rondelli, Bernardo
  • Rubio, Xavier
  • Aguilera, Antonio
  • Martín-Arroyo, Daniel
  • Mosca, Alessandro
  • Rull, Guillem
The EPNet project aims to examine the framework of the Roman economic organisation and its networks by analysing epigraphical data from amphorae. This aim is to be realised through complex network analysis, model building and computer simulation. The objective is to create an experimental laboratory for the exploration, validation and refutation of historical theories, and the formulation of new ones., Peer Reviewed

QuESo V2.0 a quality model for open source software ecosystems: List of measures

  • Franco Bedoya, Óscar Hernán
  • Ameller, David
  • Costal Costa, Dolors
  • Franch Gutiérrez, Javier
This technical report is part of QuESo-V2.0 a quality model for open source software ecosystems (OSSECOs). Our prior efforts have focused on providing a detailed list of the quality measures found during the execution of a systematic mapping on OSSECOs. In this new version of the model, we addressing some of the issues that were highlighted in the QuESo V1.0 such as: the unbalanced distribution of measures and the ambiguity of some measures names. The measures listed in this report are not intended to be an exhaustive and complete set. However, this list provides a representative collection of OSSECOs measures. It is a small step in the direction of developing a platform for support the analysis of OSSECO.

Aplicaciones diferenciales de la interferometría SAR

  • Carrasco, D
  • Esteban, D
  • Tena, J
  • López Bonillo, Francisco
  • Rodríguez, O
  • Broquetas Ibars, Antoni
Synthetic Aperture Radar Interferometry allows the coherent combination of radar images acquired from different viewpoints. The interferogram generated by substracting their phases has got information related to the geometry of the scene, i.e. the topography and small movements in the scene. The interferometric process may he therefore addressed to obtain either a Digital Elevation Model of the observed area or a precise quantitative evaluation of the movement in the scene in the radar looking direction with a precission related to the wavelenght, which is 6.4 cm in the case of the ERS European satellites. In the article we will show the interferometric process for DEM generation and the foundations of differential interferometry for small movements detection and atmospheric propagation studies with ERS examples., Peer Reviewed

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