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Impact of body wearable sensor positions on UWB ranging

  • Otim, Timothy
  • Bahillo, Alfonso
  • Díez, Luis E.
  • López Iturri, Peio
  • Falcone Lanas, Francisco Javier
In recent years, Ultrawideband (UWB) has become a very popular technology for time of flight (TOF) based localization and tracking applications but its human body interactions have not been studied yet extensively. Most UWB systems already proposed for pedestrian ranging have only been individually evaluated for a particular wearable sensor position. It is observed that wearable sensors mounted on or close to the human body can raise line-of-sight (LOS), quasi-line-of-sight (QLOS), and non-line-of-sight (NLOS) scenarios leading to significant ranging errors depending on the relative heading angle (RHA) between the pedestrian, wearable sensor, and anchors. In this paper, it is presented that not only does the ranging error depend on the RHA, but on the position of the wearable sensors on the pedestrian. Seven wearable sensor locations namely, fore-head, hand, chest, wrist, arm, thigh and ankle are evaluated and a fair comparison is made through extensive measurements and experiments in a multipath environment. Using the direction in which the pedestrian is facing, the RHA between the pedestrian, wearable sensor, and anchors is computed. For each wearable sensor location, an UWB ranging error model with respect to the human body shadowing effect is proposed. A final conclusion is drawn that among the aforementioned wearable locations, the fore-head provides the best range estimate because it is able to set low mean range errors of about 20 cm in multipath conditions. The fore-head's performance is followed by the hand, wrist, ankle, arm, thigh, and chest in that order., This work was supported in part by the Research Training Grants Program of the University of Deusto, in part by REPNIN+ under Grant TEC2017-90808-REDT and in part by Ministerio de Ciencia, Innovación y Universidades, Gobierno de España under Grant RTI2018-095499-B-C31.
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Hybrid computational techniques: electromagnetic propagation analysis in complex indoor environments

  • Azpilicueta Fernández de las Heras, Leyre
  • Falcone Lanas, Francisco Javier
  • Janaswamy, Ramakrishna
In this article, we compare deterministic methodologies for characterizing channel behavior in heterogeneous and composite scenarios. These techniques include one that combines a 3D ray launching (RL) approach based on geometrical optics (GO), a second based on GO and the uniform theory of diffraction (UTD), and another that includes a diffusion equation (DE) method based on the equation of transfer. A new methodology based on the GO and DE is presented and shown to achieve accurate results when compared with real measurements. The proposed technique provides a computational time reduction of up to 90% compared to the conventional approach using GO with the UTD and DE., This work was funded by the Ministerio de Ciencia, Innovación y Universidades, and Gobierno de España (MCIU/AEI/ FEDER,UE), RTI2018-095499-B-C31.
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AC/DC millivoltage sensor by means of ITO-coated optical fibers: towards monitoring of biosignals

  • Aginaga Etxamendi, Concepción Isabel
  • Socorro Leránoz, Abián Bentor
  • Fuentes Lorenzo, Omar
  • Del Villar, Ignacio
  • Corres Sanz, Jesús María
  • Matías Maestro, Ignacio
This contribution shows the monitoring of AC and DC millivoltage signals by means of lossy mode resonances generated by Indium Tin Oxide (ITO) on optical fibers. Sensors were obtained by sputtering ITO thin-films onto 25 mm-length segments of 200 μm bare optical fibers. Depositing a 1 μm thin-film of ITO leads to obtain reduced thin-film resistances of near 340 ohms. This allows the detection of voltage signals by monitoring the wavelength shift of the resonances. Sensitivities up to 40 nm/V can be achieved when tracking sinusoidal signals of a few cents of mV peak-to-peak. This opens the path for further research pursuing the detection of biomedical signals., This work has been supported by the Spanish National Research Agency through the project with reference TEC2016-78047-R, by the OPTISENS Government of Navarra Research Project and by a predoctoral research grant of the Public University of Navarra.
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Multimode – coreless – multimode fiber-based sensors: theoretical and experimental study

  • San Fabián García, Noé
  • Socorro Leránoz, Abián Bentor
  • Del Villar, Ignacio
  • Díaz Lucas, Silvia
  • Matías Maestro, Ignacio
This paper presents a complete study on the spectral behavior of a multimode-coreless-multimode fiber-optic structure, as well as its application as a refractometer and a liquid level sensor. The combination of two standard multimode fibers fused to a coreless fiber segment allows generating narrow interferometric bands in the optical spectrum, whose sensitivity can be improved by an adequate selection of the dimensions of the device (the coreless segment length and the diameter of the sensing area). A second way to improve the performance of the device is to deposit a thin film of SnO2, which allows increasing the sensitivity up to 314 nm/RIU. This widens the number of applications where this structure can be used. As an example, a liquid level sensor with 0.73 nm/mm sensitivity is presented., This work was supported by the Spanish Ministry of Economy and Competitiveness (TEC2016-78047-R).
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Challenges in Life Cycle Assessment (LCA) of stabilised clay-based construction materials

  • Marcelino Sádaba, Sara
  • Kinuthia, John
  • Oti, Jonathan
  • Seco Meneses, Andrés
The preference of clay-based materials for sustainable construction is well-established. The establishment ofsustainability credentials of emergent construction materials is very subjective, and most available tools are notfully equipped to deal with individual material systems, such as composite cement- or lime-based cementitioussystems, including clay-based blocks and bricks. The main problem emanates from the challenges of the audit ofeach aspect of the material processing, and especially the quantification of the most relevant inputs into thecomposite product. The variability in material ingredients, and lack of data for each aspect of the manufacturingprocesses involved creates major challenges. Incorporation of materials with long and complex recyclingprocesses further exacerbate the challenge. These incorporations create problems in terms of accurate materialtrails and data for input in a robust Life Cycle Assessment (LCA) of individual products. This paper reports on asimplified approach towards full LCA of seven clay-based brick products developed in UK (4) and Spain (3), based on known material data and estimated energy inputs in the manufacturing processes. The UK-based brickscomprise of Lower Oxford Clay (LOC), stabilised using combinations of hydrated lime, Ground Granulated Blast-furnace Slag (GGBS) and Portland cement (PC). In order to test the robustness of the proposed approach, resultson UK-based bricks are compared with a parallel LCA on clay-based product developed in Spain. Finally, theclay-based products are compared with a typical Portland cement-based concrete block andfired clay brick. Inthe LCA, boundary conditions includefixed transport, thus attempting to factor only the material ingredients,their known atmospheric emissions, and estimated energy inputs during processing. Results suggest that themost challenging aspect in the undertaking of LCA is the availability of reliable input data. Results also show thatthere are numerous parameters that can reliably and corroboratively facilitate the comparison of performance, besides carbon dioxide emissions.
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Characterization of fresh and cured properties of polymer concretes based on two metallurgical wastes

  • Seco Meneses, Andrés
  • Echeverría, Angel María
  • Marcelino Sádaba, Sara
  • García, Beñat
  • Espuelas Zuazu, Sandra
Polyester polymer concretes can substitute conventional concretes based on their usually good mechanical strength, adequate physical properties, and high resistance against aggressive chemical environments. They also show a high potential for using recycled targets in their manufacturing. This paper analyzes the fresh and cured properties of polyester polymer concretes containing two metallurgical wastes, namely: ladle slag and alumina filler. Both targets require a higher resin dosage than sand. The standard consistency test showed a low representativeness of the recycled fresh mixes’ workability. The ladle slag and alumina filler samples showed a higher length plastic shrinkage than those containing sand. All of the targets obtained cured density values in the range of 1.589–1.912 g/cm3. From a mechanical point of view, the sand and alumina filler containing polyester polymer concretes reached 11.02 and 10.93 kN, respectively, of flexural strength, while the ladle slag samples showed the best result with 19.31 kN. In the compressive strength test, the sand and alumina filler combinations reached 106.16 and 104.21 MPa, respectively, while the ladle slag achieved 160.48 MPa. The flexural and compressive elasticity modulus showed similar trends related to the resin content., This research was funded by Gobierno de Navarra and Fondo Europeo de Desarrollo Regional (FEDER) grant number [0011-1365-2017-000176], and the APC was funded by the Institute of Smart Cities of the Public University of Navarre.
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Reeb’s theorem and periodic orbits for a rotating Hénon–Heiles potential

  • Lanchares, Víctor
  • Pascual, Ana Isabel
  • Iñarrea, Manuel
  • Salas, José Pablo
  • Palacián Subiela, Jesús Francisco
  • Yanguas Sayas, Patricia
We apply Reeb’s theorem to prove the existence of periodic orbits in the rotating Hénon– Heiles system. To this end, a sort of detuned normal form is calculated that yields a reduced system with at most four non degenerate equilibrium points. Linear stability and bifurcations of equilibrium solutions mimic those for periodic solutions of the original system. We also determine heteroclinic connections that can account for transport phenomena., This work has been partly supported from the Spanish Ministry of Science and Innovation through the Projects MTM2014-59433-CO (Subprojects MTM2014-59433-C2-1-P and MTM2014-59433- C2-2-P), MTM2017-88137-CO (Subprojects MTM2017-88137-C2-1-P and MTM2017-88137-C2-2-P), and by University of La Rioja through Project REGI 2018751.
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Nazioarteko zuzenbide pribatuaren zientzia

  • Belintxon Martin, Unai
Nazioarteko Zuzenbide Pribatuaren kontzeptuak eztabaida anitzak eragin ditu urteetan zehar. Kontzeptuak, bere objektuak, bere eduki baita funtzioak ere doktrina zientifikoan gatazka ugari eragin dituzte. Guzti honen ondorioz, Nazioarteko Zuzenbide Pribatuaren inguruko kontzepzio ezberdinak topa ditzakegu.
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Contribution of systemic T cell immunity to clinical efficacy of anti-PD-L1/PD-1 immunotherapies in lung cancer

  • Zuazo Ibarra, Miren
Un alto porcentaje de pacientes con cáncer de pulmón resistentes a terapias convencionales son refractarios a la inmunoterapia con anticuerpos bloqueadores de la interacción PD-L1/PD-1. En la presente tesis doctoral se ha demostrado que la cuantificación de la proporción de linfocitos T CD4 altamente diferenciados (THD) en sangre periférica antes de comenzar el tratamiento identifica a potenciales respondedores a la inmunoterapia anti-PD-L1/PD-1. En efecto, una alta proporción de CD4 THD (>40%) pretratamiento es un indicador de la funcionalidad sistémica CD4 que resulta ser un factor diferencial para obtener respuestas clínicas. En estos pacientes, las células T CD4 son funcionales a nivel de capacidades proliferativas y presentan una baja co-expresión de PD-1/LAG-3 bajo estimulación, además de ser receptivos al bloqueo de PD-1 ex vivo e in vivo. Además, la cuantificación de los linfocitos T CD4 altamente diferenciados en combinación con la expresión positiva de PD-L1 tumoral identifica a un grupo de pacientes con una tasa de respuesta alrededor del 70%. En cambio, los pacientes con porcentajes bajos de CD4 THD (<40%) antes de comenzar el tratamiento no respondieron al bloqueo anti-PD-L1/PD-1, a pesar de presentar linfocitos T específicos de cáncer de pulmón. Aunque las células T CD4 en estos pacientes son competentes a la hora de producir de citoquinas, son disfuncionales a nivel de proliferación, co-expresan altos niveles de PD-1/LAG-3 y son refractarios al monobloqueo de PD-1. Así, la inmunidad sistémica CD8 solo pudo ser revertida a través del bloqueo de PD-L1/PD-1 en aquellos pacientes que presentaban una inmunidad CD4 basal funcional. En cambio, la disfuncionalidad proliferativa observada en las células T de pacientes refractarios a la inmunoterapia anti-PD-L1/PD-1 pudo revertirse a través del doble bloqueo de PD-1/LAG‐3. De esta manera, mediante los presentes datos se ha confirmado que la co-expresión de PD-1/LAG-3 contribuye a la disfuncionalidad de las células T en pacientes con cáncer de pulmón resistentes a terapias convencionales. Estos resultados proporcionan el fundamento experimental para la combinación de las terapias bloqueadoras de PD-L1/PD-1 y LAG-3 en pacientes que manifiestan una inmunidad CD4 basal disfuncional., A high percentage of lung cancer patients progressing from conventional therapies are refractory to PD‐L1/PD‐1 blockade monotherapy. Here, we show that the proportion of highly differentiated (THD) CD4 T cell population can identify potential responders to PD-L1/PD-1 blockade therapy as quantified from peripheral blood samples before treatment initiation. Indeed, a baseline high proportion of CD4 THD (>40%) is an indicator of functional systemic CD4 immunity which turned to be a differential factor for clinical responses. In these patients, CD4 T cells possessed significant proliferative capacities and low co‐expression of PD‐1/LAG‐3 following activation, and were responsive to PD‐1 blockade ex vivo and in vivo. In addition, quantification of highly differentiated CD4 T cells in combination with PD‐L1 tumor positivity identified a group of patients with response rates to immunotherapy of about 70%. In contrast, patients with low percentages of CD4 THD (<40%) did not respond even though they had lung cancer‐specific T cells. Although proficient in cytokine production, CD4 T cells in these patients exhibited proliferative dysfunctionality, strongly co‐upregulated PD‐1/LAG‐3 and were largely refractory to PD‐1 monoblockade. Systemic CD8 immunity only recovered by PD-L1/PD-1 blockade therapy in patients who had baseline functional CD4 immunity. In contrast, baseline systemic T cell proliferative dysfunctionality in patients refractory to PD-1/PD-L1 monoblockade strategies could be reverted by PD‐1/LAG‐3 co‐blockade confirming that PD-1/LAG-3 co-expression was a contributor to T cell dysfunctionality. These results provide a strong rationale for the combination of PD-L1/PD-1 and LAG-3 blockade therapies in patients exhibiting baseline CD4 T cell dysfunctionality., Ayudas para la formación de Personal Investigador de la Universidad Pública de Navarra para la realización de tesis doctorales 2017 Universidad Pública de Navarra (UPNA); Ayudas a la Movilidad de doctorandos UPNA 2018-2019; Desarrollo de una nueva generación de vacunas genéticas para el tratamiento de melanoma. Gobierno de Navarra. Proyectos de Biomedicina 2014. BMED 033-2014; Efectos de la senescencia inmunológica sobre la eficacia de las inmunoterapias anti-PD-L1/anti-PD-1. Proyectos Asociación Española Contra el Cáncer (AECC) 2017; Impacto de la Inmunoterapia anti-PD-L1/PD-1 sobre las capacidades anti-tumorales de los linfocitos T humanos en diferentes estadios de diferenciación. PI17/02119. Instituto de Salud Carlos III., Programa de Doctorado en Ciencias de la Salud (RD 99/2011), Osasun Zientzietako Doktoretza Programa (ED 99/2011)
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Tendances internationales de la mortalité maternelle et infantile en Afrique de 1990-2016

  • Onambele, Luc
Objectif général: savoir la tendance annuelle de réduction du taux de mortalité maternelle et infantile entre 1990 à 2015 et 2016 respectivement. Objectifs spécifiques: savoir les tendances annuelles de réduction de la mortalité maternelle dans les cinq régions de l‘Afrique; savoir les pays africains qui ont atteint le quatrième Objectif du Millénaire pour le Développement (OMD4); savoir les tendances annuelles de mortalité infantile dans les cinq régions de l‘Afrique; savoir les pays africains ayant atteint le cinquième Objectif du Millénaire pour le Développement(OMD5); savoir la région dont les pays ont les meilleures tendances annuelles de réduction de la mortalité maternelle et infantile., Programa de Doctorado en Ciencias de la Salud (RD 99/2011), Osasun Zientzietako Doktoretza Programa (ED 99/2011)
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