3,042 research outputs found
Discriminación Mejorada Entre Personas Sanas e Hipertensas Combinando Fotopletismografía y Electrocardiografía
[ES] Las enfermedades cardiovasculares son una de las principales
causas de muerte, siendo la hipertensión arterial (HTA) su principal factor de riesgo. Sus complicaciones pueden evitarse con
un tratamiento temprano, pero dado que estos pacientes no presentan ninguna sintomatología, a menudo la HTA se detecta en
estadios muy avanzados. Este trabajo presenta un modelo de estimación de la presión arterial (PA) a partir de señales de electrocardiografía (ECG) y fotopletismografía (PPG), que pueden
obtenerse del paciente con facilidad mediante dispositivos llevables de monitorización continua. Se han analizado señales de
86 pacientes con registros de ECG, PPG y PA, siendo 35 normotensos, 26 prehipertensos y 25 hipertensos. Los registros fueron limpiados de ruido para mejorar la obtención de sus puntos
característicos. A partir de ellos se obtuvieron parámetros discriminatorios como los tiempos de llegada de pulso (PAT) y características morfológicas de la señal PPG como el ancho del
pulso e intervalo entre picos sistólicos, con los que se entrenarán modelos de clasificación buscando mejorar los resultados de
discriminación entre pacientes. Los resultados obtenidos fueron
del 85,44 % de F1 score comparando a pacientes normotensos
con prehipertensos e hipertensos, logrando una mejora del 7 %
respecto a la utilización de parámetros predictivos y clasificadores propuestos en estudios previos. La utilización de las señales
PPG y ECG ha demostrado ser capaz de discriminar entre personas sanas e hipertensas y, por tanto, podría ser usada para
la prevención de la hipertensión implementando esta técnica en
dispositivos llevables.El presente trabajo ha sido cofinanciado por los proyectos
de investigación competitiva DPI2017-83952-C3 de
MINECO-AEI-FEDER-UE, SBPLY/17/180501/000411
de la JCCLM y AICO/2019/036 de la GVA.Cano Serrano, J.; Alcaraz Martinez, R.; Rieta, JJ. (2020). Discriminación Mejorada Entre Personas Sanas e Hipertensas Combinando Fotopletismografía y Electrocardiografía. Sociedad Española de Ingeniería Biomédica. 2-5. http://hdl.handle.net/10251/178258S2
The pathway to secondary prevention of Alzheimer\u27s disease
Alzheimer\u27s disease (AD) is a continuum consisting of a preclinical stage that occurs decades before symptoms appear. As researchers make advances in investigating the continuum, the importance of developing drugs for secondary prevention is garnering increased discussion. For efficacious drug development for secondary prevention it is important to define what are the earliest biological stages of AD. The Alzheimer\u27s Association Research Roundtable convened November 27 to 28, 2018 to focus on pre-clinical AD. This review will address the biological approach to defining pre-clinical AD, detection, identification of at-risk individuals, and lessons learned from trials such as A4 and TOMMORROW
Computer simulations of VANETs using realistic city topologies
Researchers in vehicular ad hoc networks (VANETs) commonly use simulation
to test new algorithms and techniques. This is the case because of the high cost and labor
involved in deploying and testing vehicles in real outdoor scenarios. However, when determining
the factors that should be taken into account in these simulations, some factors such
as realistic road topologies and presence of obstacles are rarely addressed. In this paper,
we first evaluate the packet error rate (PER) through actual measurements in an outdoor
road scenario, and deduce a close model of the PER for VANETs. Secondly, we introduce a
topology-based visibility scheme such that road dimension and geometry can be accounted
for, in addition to line-of-sight. We then combine these factors to determine when warning
messages (i.e., messages that warn drivers of danger and hazards) are successfully received
in a VANET. Through extensive simulations using different road topologies, city maps, and
visibility schemes, we show these factors can impact warning message dissemination time
and packet delivery rate.This work was partially supported by the Ministerio de Educacion y Ciencia, Spain, under Grant TIN2011-27543-C03-01, and by the Diputacion General de Aragon, under Grant "subvenciones destinadas a la formacion y contratacion de personal investigador".Martínez, FJ.; Fogue, M.; Toh, C.; Cano Escribá, JC.; Tavares De Araujo Cesariny Calafate, CM.; Manzoni, P. (2013). Computer simulations of VANETs using realistic city topologies. Wireless Personal Communications. 69(2):639-663. https://doi.org/10.1007/s11277-012-0594-6S639663692Martinez F. J., Toh C.-K., Cano J.-C., Calafate C. T., Manzoni P. (2011) A survey and comparative study of simulators for vehicular ad hoc networks (VANETs). Wireless Communications and Mobile Computing Journal 11(7): 813–828Toh C.-K. (2001) Ad hoc mobile wireless networks: Protocols and systems. Prentice Hall, Englewood Cliffs, NJIEEE 802.11 Working Group. (2010). IEEE standard for information technology—telecommunications and information exchange between systems—local and metropolitan area networks—Specific requirements—Part 11: Wireless LAN medium access control (MAC) and physical layer (PHY) specifications amendment 6: Wireless Access in Vehicular Environments.Sommer, C., Eckhoff, D., German, R., & Dressler F. (2011). A computationally inexpensive empirical model of IEEE 802.11p radio shadowing in urban environments. In Eighth international conference on wireless on-demand network systems and services (WONS), pp. 84–90.Bohm, A., Lidstrom, K., Jonsson, M., & Larsson, T. (2010). Evaluating CALM M5-based vehicle-to-vehicle communication in various road settings through field trials. In Proceedings of the 35th IEEE conference on local computer networks (LCN’10), Denver, Colorado, USA, pp. 613–620.Martinez, F. J., Fogue, M., Coll, M., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2010). Assessing the impact of a realistic radio propagation model on VANET scenarios using real maps. In 9th IEEE international symposium on network computing and applications (NCA), Boston, USA, pp. 132–139.Fall, K., & Varadhan, K. (2000). “ns notes and documents,” The VINT project. UC Berkeley, LBL, USC/ISI, and Xerox PARC, February 2000. Available at http://www.isi.edu/nsnam/ns/ns-documentation.html .Marinoni, S., & Kari, H. H. (2006). Ad hoc routing protocol performance in a realistic environment. In Proceedings of the international conference on networking, international conference on systems and international conference on mobile communications and learning technologies (ICN/ICONS/MCL 2006), Washington, DC, USA.Mahajan, A., Potnis, N., Gopalan, K., & Wang, A. (2007). Modeling VANET deployment in urban settings. In International workshop on modeling analysis and simulation of wireless and mobile systems (MSWiM 2007), Crete Island, Greece.Suriyapaiboonwattana, K., Pornavalai, C., & Chakraborty, G. (2009). An adaptive alert message dissemination protocol for VANET to improve road safety. In IEEE intlernational conference on fuzzy systems, 2009. FUZZ-IEEE 2009, pp. 1639–1644.Bako, B., Schoch, E., Kargl, F., & Weber, M. (2008). Optimized position based gossiping in VANETs. In Vehicular technology conference, 2008. VTC 2008-Fall. IEEE 68th, pp. 1–5.Martinez, F. J., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2008). Citymob: A mobility model pattern generator for VANETs. In IEEE vehicular networks and applications workshop (Vehi-Mobi, held with ICC), Beijing, China.Torrent-Moreno, M., Santi, P., & Hartenstein, H. (2007). Inter-vehicle communications: Assessing information dissemination under safety constraints. In Proceedings of the 4th annual conference on wireless on demand network systems and services (WONS), Oberguyrgl, Austria.Martinez, F. J., Toh, C.-K., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2009). Realistic radio propagation models (RPMs) for VANET simulations. In IEEE wireless communications and networking conference (WCNC), Budapest, Hungary.Martinez, F. J., Toh, C.-K., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2010). A street broadcast reduction scheme (SBR) to mitigate the broadcast storm problem in VANETs. Wireless personal communications, pp. 1–14. doi: 10.1007/s11277-010-9989-4Ni, S.-Y., Tseng, Y.-C., Chen, Y.-S., & Sheu, J.-P. (1999). The broadcast storm problem in a mobile ad hoc network. In ACM/IEEE international conference on mobile computing and networking (MobiCom 1999), Seattle Washington.Krajzewicz, D., & Rossel, C. (2007). “Simulation of urban mobility (SUMO),” Centre for Applied Informatics (ZAIK) and the Institute of Transport Research at the German Aerospace Centre. Available at http://sumo.sourceforge.net/index.shtml .OpenStreetMap Team. (2009). OpenStreetMap, collaborative project to create a free editable map of the world. Available at http://www.openstreetmap.org .U.S. Census Bureau. (2009). TIGER, topologically integrated geographic encoding and referencing. Available at http://www.census.gov/geo/www/tiger .Krauss S., Wagner P., Gawron C. (1997) Metastable states in a microscopic model of traffic flow. Physical Review E 55(5): 5597–5602Krajzewicz, D., Hertkorn, G., Rossel, C., & Wagner, P. (2002). SUMO (Simulation of Urban MObility)—An open-source traffic simulation. In Proceedings of the 4th middle east symposium on simulation and modelling (MESM2002), Sharjah, United Arab Emirates, pp. 183–187
P 388 Diagnostic value of polymerase chain reaction of aqueous and vitreous humor for infectious uveitis in AIDS patients
Providing resilience to UAV swarms following planned missions
As we experience an unprecedented growth in the field of Unmanned Aerial Vehicles (UAVs), more and more applications keep arising due to the combination of low cost and flexibility provided by these flying devices, especially those of the multirrotor type. Within this field, solutions where several UAVs team-up to create a swarm are gaining momentum as they enable to perform more sophisticated tasks, or accelerate task execution compared to the single-UAV alternative. However, advanced solutions based on UAV swarms still lack significant advancements and validation in real environments to facilitate their adoption and deployment. In this paper we take a step ahead in this direction by proposing a solution that improves the resilience of swarm flights, focusing on handling the loss of the swarm leader, which is typically the most critical condition to be faced. Experiments using our UAV emulation tool (ArduSim) evidence the correctness of the protocol under adverse circumstances, and highlight that swarm members are able to seamlessly switch to an alternative leader when necessary, introducing a negligible delay in the process in most cases, while keeping this delay within a few seconds even in worst-case conditions
Using topology and neighbor information to overcome adverse vehicle density conditions
Vehicular networks supporting cooperative driving on the road have attracted much attention due to the plethora of new possibilities they offer to modern Intelligent Transportation Systems. However, research works regarding vehicular networks usually obviate assessing their proposals in scenarios including adverse vehicle densities, i.e., density values that significantly differ from the average values, despite such densities can be quite common in real urban environments (e.g. traffic jams). In this paper, we study the effect of these hostile conditions on the performance of different schemes providing warning message dissemination. The goal of these schemes is to maximize message delivery effectiveness, something difficult to achieve in adverse density scenarios. In addition, we propose the Neighbor Store and Forward (NSF) scheme, designed to be used under low density conditions, and the Nearest Junction Located (NJL) scheme, specially developed for high density conditions. Simulation results demonstrate that our proposals are able to outperform existing warning message dissemination schemes in urban environments under adverse vehicle density conditions. In particular, NSF reduces the warning notification time in low vehicle density scenarios, while increasing up to 23.3% the percentage of informed vehicles. As for high vehicle density conditions, NJL is able to inform the same percentage of vehicles than other existing approaches, while reducing the number of messages up to 46.73%This work was partially supported by the Ministerio de Ciencia e Innovacion, Spain, under Grant TIN2011-27543-C03-01, by the Fundacion Universitaria Antonio Gargallo and the Obra Social de Ibercaja, under Grant 2013/B010, as well as the Government of Aragon and the European Social Fund (T91 Research Group).Sanguesa, JA.; Fogue, M.; Garrido, P.; Martinez, FJ.; Cano Escribá, JC.; Tavares De Araujo Cesariny Calafate, CM. (2014). Using topology and neighbor information to overcome adverse vehicle density conditions. Transportation Research Part C: Emerging Technologies. 42:1-13. https://doi.org/10.1016/j.trc.2014.02.010S1134
Determining the representative factors affecting warning message dissemination in VANETs
In this paper, we present a statistical analysis based on the 2k factorial methodology
to determine the representative factors affecting traffic safety applications in Vehicular
ad hoc networks (VANETs). Our purpose is to determine what are the key factors affecting
Warning Message Dissemination (WMD) in order to concentrate on such parameters,
thus reducing the amount of required simulation time when evaluating VANETs. Simulation
results show that the key factors affecting warning messages delivery are: (i) the transmission
range, (ii) the radio propagation model used, and (iii) the density of vehicles. Based on this
statistical analysis, we evaluate a compound key factor: neighbor density. This factor combines
the above-mentioned factors into a single entity, reducing the number of factors that
must be taken into account for VANET researchers to evaluate the benefits of their proposals.This work was partially supported by the Ministerio de Educacion y Ciencia, Spain, under Grant TIN2008-06441-C02-01, and by the Fundacion Antonio Gargallo, under Grant 2009/B001.Martínez Domínguez, FJ.; Toh, CK.; Cano Escribá, JC.; Tavares De Araujo Cesariny Calafate, CM.; Manzoni, P. (2012). Determining the representative factors affecting warning message dissemination in VANETs. Wireless Personal Communications. 67(2):295-314. https://doi.org/10.1007/s11277-010-9989-4S295314672Eichler, S. (2007). Performance evaluation of the IEEE 802.11p WAVE communication standard. In Proceedings of the vehicular technology conference (VTC-2007 Fall), USA.Fall, K., & Varadhan, K. (2000). ns notes and documents. The VINT Project. UC Berkeley, LBL, USC/ISI, and Xerox PARC. Available at http://www.isi.edu/nsnam/ns/ns-documentation.html .Fasolo, E., Zanella, A., & Zorzi, M. (2006). An effective broadcast scheme for alert message propagation in vehicular ad hoc networks. In Proceedings of the IEEE International Conference on Communications, Istambul, Turkey.Korkmaz, G., Ekici, E., Ozguner, F., & Ozguner, U. (2004). Urban multi-hop broadcast protocols for inter-vehicle communication systems. In Proceedings of First ACM Workshop on Vehicular Ad Hoc Networks (VANET 2004).Martinez, F. J., Toh, C.-K., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2009). Realistic radio propagation models (RPMs) for VANET simulations. In IEEE wireless communications and networking conference (WCNC), Budapest, Hungary.Martinez, F. J., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2008). CityMob: A mobility model pattern generator for VANETs. In IEEE vehicular networks and applications workshop (Vehi-Mobi, held with ICC), Beijing, China.Martinez, F. J., Cano, J.-C., Calafate, C. T., & Manzoni, P. (2009). A performance evaluation of warning message dissemination in 802.11p based VANETs. In IEEE local computer networks conference (LCN 2009), Zürich, Switzerland.Torrent-Moreno, M., Santi, P., & Hartenstein, H. (2005). Fair sharing of bandwidth in VANETs. In Proceedings of the 2nd ACM international workshop on vehicular ad hoc networks, Germany.Tseng Y.-C., Ni S.-Y., Chen Y.-S., Sheu J.-P. (2002) The broadcast storm problem in a mobile ad hoc network. Wireless Networks 8: 153–167Wisitpongphan N., Tonguz O., Parikh J., Mudalige P., Bai F., Sadekar V. (2007) Broadcast storm mitigation techniques in vehicular ad hoc networks. Wireless Communications IEEE 14(6): 84–94. doi: 10.1109/MWC.2007.4407231Yang, X., Liu, J., Zhao, F., & Vaidya, N. H. (2004). A vehicle-to-vehicle communication protocol for cooperative collision warning. In Proceedings of the first annual international conference on mobile and ubiquitous systems: Networking and services (MobiQuitous’04).Yoon, J., Liu, M., & Noble, B. (2003). Random waypoint considered harmful. Proceedings of IEEE INFOCOMM 2003, San Francisco, California, USA.Zang, Y., Stibor, L., Cheng, X., Reumerman, H.-J., Paruzel, A., & Barroso, A. (2007). Congestion control in wireless networks for vehicular safety applications. In Proceedings of the 8th European Wireless Conference, Paris, France
In response to: Comment on “Review of Dohan Eherenfest et al. (2009) on “Classification of platelet concentrates: From pure platelet-rich plasma (P-PRP) to leucocyte- and platelet-rich fibrin (L-PRF)”
VEACON: A Vehicular Accident Ontology designed to improve safety on the roads
[EN] Vehicles are nowadays provided with a variety of new sensors capable of gathering information about themselves and from their surroundings. In a near future, these vehicles will also be capable of sharing all the harvested information, with the surrounding environment and among nearby vehicles over smart wireless links. They will also be able to connect with emergency services in case of accidents. Hence, distributed applications based on Vehicular Networks (VNs) will need to agree on a `common understanding¿ of context for interoperability, and, therefore, it is necessary to create a standard structure which enables data interoperability among all the different entities involved in transportation systems. In this paper, we focus on traffic safety applications; specifically, we present the VEhicular ACcident ONtology (VEACON) designed to improve traffic safety. Our ontology combines the information collected when an accident occurs, and the data available in the General Estimates System (GES) accidents database. We assess the reliability of our proposal using both realistic crash tests, held in the facilities of Applus+ IDIADA in Tarragona, Spain, and Vehicular Network simulations, based on the ns-2 simulation tool. Experimental results highlight that both nearby vehicles and infrastructure elements (RSUs) are correctly notified about an accident in just a few seconds, increasing the emergency services notification effectiveness. (c) 2012 Elsevier Ltd. All rights reserved.This work was partially supported by the Ministerio de Ciencia e Innovacion, Spain, under Grant TIN2011-27543-C03-01.Barrachina, J.; Garrido, P.; Fogue, M.; Martínez, FJ.; Cano Escribá, JC.; Tavares De Araujo Cesariny Calafate, CM.; Manzoni, P. (2012). VEACON: A Vehicular Accident Ontology designed to improve safety on the roads. Journal of Network and Computer Applications. 35(6):1891-1900. https://doi.org/10.1016/j.jnca.2012.07.013S1891190035
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