Person:
Fernández Valdivielso, Carlos

person.page.identifierURI

https://academica-e.unavarra.es/handle/2454/49023

Last Name

Fernández Valdivielso

First Name

Carlos

person.page.departamento

Ingeniería Eléctrica, Electrónica y de Comunicación

ORCID

0009-0005-3397-5861

person.page.upna

2704

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Now showing 1 - 10 of 13

Open Access
Generation of lossy mode resonances by deposition of high-refractive-index coatings on uncladded multimode optical fibers
(IOP Publishing Ltd, 2010) Del Villar, Ignacio; Ruiz Zamarreño, Carlos; Sánchez Zábal, Pedro; Hernáez Sáenz de Zaitigui, Miguel; Fernández Valdivielso, Carlos; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
A comparative study of lossy mode resonances generated by depositing two different materials is presented. The two materials selected are indium tin oxide (ITO) and indium oxide. The two materials present different dielectric dispersion, which leads to the generation of single-peak lossy mode resonances with the ITO coated optical fibers and dual-peak lossy mode resonances with the In2O3 coated optical fibers. The obvious advantage of a dual-peak based measurement in the sensors field is enhanced by a sensitivity increase observed in sensors based on In2O3 if compared with those based on ITO. These characteristics are analyzed both theoretically and experimentally.
Open Access
Development of a low mobility IEEE 802.15.4 compliant VANET system for urban environments
(MDPI, 2013) Nazábal Urriza, Juan Antonio; Falcone Lanas, Francisco; Fernández Valdivielso, Carlos; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua: Ref. IIM010566. RI1
The use of Vehicular Ad-Hoc Networks (VANETs) is growing nowadays and it includes both roadside-to-vehicle communication (RVC) and inter-vehicle communication (IVC). The purpose of VANETs is to exchange useful information between vehicles and the roadside infrastructures for making an intelligent use of them. There are several possible applications for this technology like: emergency warning system for vehicles, cooperative adaptive cruise control or collision avoidance, among others. The objective of this work is to develop a VANET prototype system for urban environments using IEEE 802.15.4 compliant devices. Simulation-based values of the estimated signal strength and radio link quality values are obtained and compared with measurements in outdoor conditions to validate an implemented VANET system. The results confirm the possibility of implementing low cost vehicular communication networks operating at moderate vehicular speeds.
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
An analysis matrix for the assessment of smart city technologies: main results of its application
(MDPI, 2017) Branchi, Pablo Emilio; Fernández Valdivielso, Carlos; Matías Maestro, Ignacio; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
The paper presents the main results of a previously developed methodology to better evaluate new technologies in Smart Cities, using a tool to evaluate different systems and technologies regarding their usefulness, considering each application and how technologies can impact the physical space and natural environment. Technologies have also been evaluated according to how they are used by citizens, who must be the main concern of all urban development. Through a survey conducted among the Smart City Spanish network (RECI) we found that the ICT’s that change our cities everyday must be reviewed, developing an innovative methodology in order to find an analysis matrix to assess and score all the technologies that affect a Smart City strategy. The paper provides the results of this methodology regarding the three main aspects to be considered in urban developments: mobility, energy efficiency, and quality of life after obtaining the final score for every analyzed technology. This methodology fulfills an identified need to study how new technologies could affect urban scenarios before being applied, developing an analysis system to be used by urban planners and policy-makers to decide how best to use them, and this paper tries to show, in a simple way, how they can appreciate the variances between different solutions.
Open Access
Towards personal privacy control
(Springer, 2007) Alcalde Bagüés, Susana; Zeidler, Andreas; Fernández Valdivielso, Carlos; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
In this paper we address the realization of personal privacy control in the era of pervasive computing. How could an individual meet his/her expected level of privacy? how could the system guaranty that a user privacy criteria is fulfilled?. For that an elaborate set of requirements for personal privacy is given followed with the implementation of our SenTry policy language.
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
Efectividad de la atención primaria de salud en el diagnóstico y tratamiento de la hipertensión arterial
(Gobierno de Navarra, 2008) Brugos Larumbe, Antonio; Guillén Grima, Francisco; Díez, J.; Buil, P.; Ciaurriz, M.; Fernández Valdivielso, Carlos; Cenoz, J. C.; Ciencias de la Salud; Osasun Zientziak
La hipertensión arterial (HTA) es un importante problema de salud pública, por su elevada morbimortalidad cardiovascular y sus costes económicos y sociales. Fundamento. Identificar la prevalencia de HTA detectada en atención primaria y su grado de control; conocer los tipos de tratamientos utilizados y factores asociados a su control. Pacientes y métodos. Estudio transversal comparativo de dos años en el Centro de Salud de Villava. Se analizan los datos de la historia clínica informatizada en los años 2003 y 2006. Se estudian las variables: edad, género, pensión arterial sistólica y diastólica, colesterol total, HDL, LDL, triglicéridos, tabaquismo, índice de masa corporal en ambos años. Tratamiento hipotensor en el año 2006. Mediante regresión logística se identifican las variables del año 2006 asociadas a buen control. Resultados. Prevalencia detectada de HTA en ≥18 años: 2003: 11,6% (IC:10,9-12,3); 2006: 16,6% (IC:15,8-17,4) (p<0,001). En hipertensos con registro de presión arterial estaban controlados (PA:<140/90) en 2003: 45,1% (IC: 41,0- 48,0) y en 2006: 40,4% (IC: 37,7-43,2) (p<0,05). Variables asociadas a buen control: ser varón [OR 1,60 (IC: 1,26-2,03)] tratamiento con ARA II [OR 2,16 (IC: 1,50-3,09)] y ser diabético [OR 1,50 (IC: 1,10-2,03]. Se asocian a mal control: presentar enfermedad vascular cerebral, vasculopatía periférica y el tratamiento con IECA. Conclusiones. La prevalencia de HTA detectada es baja. El nivel de control es superior para la PAD que para la PAS. El tratamiento con ARA II, ser varón o ser diabético se asocia a mejor control. La vasculopatía periférica, la cardiopatía isquémica, la enfermedad vascular cerebral, el tratamiento con IECA y edad se asocian a peor control.
Open Access
Design rules for lossy mode resonance based sensors
(Optical Society of America, 2012) Del Villar, Ignacio; Hernáez Sáenz de Zaitigui, Miguel; Ruiz Zamarreño, Carlos; Sánchez Zábal, Pedro; Fernández Valdivielso, Carlos; Arregui San Martín, Francisco Javier; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
Lossy mode resonances can be obtained in the transmission spectrum of cladding removed multimode optical fiber coated with a thin-film. The sensitivity of these devices to changes in the properties of the coating or the surrounding medium can be optimized by means of the adequate parameterization of the coating refractive index, the coating thickness and the surrounding medium refractive index (SMRI). Some basic rules of design, which enable the selection of the best parameters for each specific sensing application, are indicated in this work.
Unknown
Enabling personal privacy for pervasive computing environments
(Graz University of Technology, IICM, 2010) Alcalde Bagüés, Susana; Zeidler, Andreas; Klein, Cornel; Fernández Valdivielso, Carlos; Matías Maestro, Ignacio; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa
Protection of personal data in the Internet is already a challenge today. Users have to actively look up privacy policies of websites and decide whether they can live with the terms of use. Once discovered, they are forced to make a ”‘take or leave”’ decision. In future living and working environments, where sensors and context-aware services are pervasive, this becomes an even greater challenge and annoyance. The environment is much more personalized and users cannot just ”‘leave”’. They require measures to prevent, avoid and detect misuse of sensitive data, as well as to be able to negotiate the purpose of use of data. We present a novel model of privacy protection, complementing the notion of enterprise privacy with the incorporation of personal privacy towards a holistic privacy management system. Our approach allows non-expert users not only to negotiate the desired level of privacy in a rather automated and simple way, but also to track and monitor the whole life-cycle of data.
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Performance analysis of IEEE 802.15.4 compliant wireless devices for heterogeneous indoor home automation environments
(Hindawi, 2012) Nazábal Urriza, Juan Antonio; López Iturri, Peio; Azpilicueta Fernández de las Heras, Leyre; Falcone Lanas, Francisco; Fernández Valdivielso, Carlos; Ingeniería Eléctrica y Electrónica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
The influence of topology as well as morphology of complex indoor scenarios in the deployment of wireless sensor networks and wireless systems applied to home and building automation systems is analyzed. The existence of loss mechanisms such as material absorption (walls, furniture, etc.) and strong multipath components as well as the increase in the number of wireless sensors within indoor scenarios increases the relevance in the configuration of the heterogeneous wireless systems. Simulation results by means of empirical-based models are compared with an in-house 3D ray launching code as well as measurement results from wireless sensor networks illustrate the strong influence of the indoor scenario in the overall performance. The use of adequate radioplanning strategies lead to optimal wireless network deployments in terms of capacity, quality of service, and reduced power consumption.