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ArduSim: Accurate and real-time multicopter simulation

  • Fabra Collado, Francisco Jose
  • Tavares De Araujo Cesariny Calafate, Carlos Miguel|||0000-0001-5729-3041
  • Cano, Juan-Carlos|||0000-0002-0038-0539
  • Manzoni, Pietro|||0000-0003-3753-0403
[EN] As the popularity and the number of Unmanned Aerial Vehicles (UAVs) increases, new protocols are needed to coordinate UAVs when flying autonomously, and to avoid that these UAVs collide with each other. Directly testing such novel protocols on real UAVs is a complex procedure that requires investing much time, money and research effort. Hence, it becomes necessary to have the possibility to first test different solutions using simulation. Unfortunately, existing tools present significant limitations: some of them only simulate accurately the flight behavior of one UAV, while some other simulators can manage several UAVs simultaneously, but not in real-time, thus loosing accuracy regarding the mobility pattern of the UAV. In this work we address such problem by introducing ArduSim, a novel simulator that allows controlling in soft real-time the flight and communications of multiple UAVs, being the developed protocols directly portable to real devices. The contributions of this work include: (i) the ArduSim simulation platform, which allows realistic simulation and control of multiple UAVs simultaneously, offering functionalities not provided by existing alternatives; (ii) a model for the WiFi communications link between UAVs, based on real experiments, and that is integrated into ArduSim itself; and (iii) a thorough study of the scalability performance of our simulator., This work was supported by the Ministerio de Economia y Competitividad for the "Programa Estatal de Investigacion, Desarrollo e Innovacion Orientada a Retos de la Sociedad, Proyecto I+D+I SMART@CARPHONE: Integracion del smartphone y el vehiculo para conectar conductores, sensores y entorno a traves de una arquitectura de servicios funcionales" (grant number TEC2014-52690-R), and the Universitat Politecnica de Valencia (UPV) under program "Contratos Pre-doctorales para la Formacion de Personal Investigador (FPI)" (grant number 0060100000).

Arabidopsis ILITHYIA protein is necessary for proper chloroplast biogenesis and root development independent of eIF2alpha phosphorylation

  • Faus, I.
  • Niñoles Rodenes, Regina|||0000-0002-7862-9509
  • Kesari, V.
  • Llabata, P.
  • Tam, E.
  • Nebauer, Sergio G.
  • Santiago, J.
  • Hauser, M.T.
  • Gadea Vacas, José|||0000-0002-3612-7914
[EN] One of the main mechanisms blocking translation after stress situations is mediated by phosphorylation of the alpha-subunit of the eukaryotic initiation factor 2 (eIF2), performed in Arabidopsis by the protein kinase GCN2 which interacts and is activated by ILITHYIA(ILA). ILA is involved in plant immunity and its mutant lines present phenotypes not shared by the gcn2 mutants. The functional link between these two genes remains elusive in plants. In this study, we show that, although both ILA and GCN2 genes are necessary to mediate eIF2 alpha phosphorylation upon treatments with the aromatic amino acid biosynthesis inhibitor glyphosate, their mutants develop distinct root and chloroplast phenotypes. Electron microscopy experiments reveal that ila mutants, but not gcn2, are affected in chloroplast biogenesis, explaining the macroscopic phenotype previously observed for these mutants. ila3 mutants present a complex transcriptional reprogramming affecting defense responses, photosynthesis and protein folding, among others. Double mutant analyses suggest that ILA has a distinct function which is independent of GCN2 and eIF2 alpha phosphorylation. These results suggest that these two genes may have common but also distinct functions in Arabidopsis., Microarray experiments were done in the Genomics Facility of the IBMCP. MTH was supported by the Austrian Science Found (FWF) projectF03707. This work has been supported by the Spanish Ministry for Science and Education (Plan Nacional 2008-2011).

Experimental Phantom-Based Security Analysis for Next-Generation Leadless Cardiac Pacemakers

  • Awan, Muhammad Faheem
  • Perez-Simbor, Sofia
  • Garcia-Pardo, Concepcion|||0000-0002-2774-980X
  • Kansanen, Kimmo
  • Cardona Marcet, Narciso
[EN] With technological advancement, implanted medical devices can treat a wide range of chronic diseases such as cardiac arrhythmia, deafness, diabetes, etc. Cardiac pacemakers are used to maintain normal heart rhythms. The next generation of these pacemakers is expected to be completely wireless, providing new security threats. Thus, it is critical to secure pacemaker transmissions between legitimate nodes from a third party or an eavesdropper. This work estimates the eavesdropping risk and explores the potential of securing transmissions between leadless capsules inside the heart and the subcutaneous implant under the skin against external eavesdroppers by using physical-layer security methods. In this work, we perform phantom experiments to replicate the dielectric properties of the human heart, blood, and fat for channel modeling between in-body-to-in-body devices and from in-body-to-off-body scenario. These scenarios reflect the channel between legitimate nodes and that between a legitimate node and an eavesdropper. In our case, a legitimate node is a leadless cardiac pacemaker implanted in the right ventricle of a human heart transmitting to a legitimate receiver, which is a subcutaneous implant beneath the collar bone under the skin. In addition, a third party outside the body is trying to eavesdrop the communication. The measurements are performed for ultrawide band (UWB) and industrial, scientific, and medical (ISM) frequency bands. By using these channel models, we analyzed the risk of using the concept of outage probability and determine the eavesdropping range in the case of using UWB and ISM frequency bands. Furthermore, the probability of positive secrecy capacity is also determined, along with outage probability of a secrecy rate, which are the fundamental parameters in depicting the physical-layer security methods. Here, we show that path loss follows a log-normal distribution. In addition, for the ISM frequency band, the probability of successful eavesdropping for a data rate of 600 kbps (Electromyogram (EMG)) is about 97.68% at an eavesdropper distance of 1.3 m and approaches 28.13% at an eavesdropper distance of 4.2 m, whereas for UWB frequency band the eavesdropping risk approaches 0.2847% at an eavesdropper distance of 0.22 m. Furthermore, the probability of positive secrecy capacity is about 44.88% at eavesdropper distance of 0.12 m and approaches approximately 97% at an eavesdropper distance of 0.4 m for ISM frequency band, whereas for UWB, the same statistics are 96.84% at 0.12 m and 100% at 0.4 m. Moreover, the outage probability of secrecy capacity is also determined by using a fixed secrecy rate., This work was supported by the Marie Curie Research Grants Scheme, with project grant no 675353, EU Horizon 2020-WIBEC ITN 00 (Wireless In-Body Environment). Details can be found at a source https://cordis.europa.eu/project/rcn/198286_en.html.

Distribution of Road Hazard Warning Messages to Distant Vehicles in Intelligent Transport Systems

  • Calabuig Soler, Daniel|||0000-0003-0611-9902
  • Martín-Sacristán, David|||0000-0002-7781-557X
  • Monserrat del Río, Jose Francisco
  • Botsov, Mladen
  • Gozálvez Serrano, David
[EN] The efficient distribution of intelligent transport system (ITS) messages is fundamental for the deployment and acceptance of ITS applications by mobile network operators and the automotive industry. In particular, the distribution of road hazard warning (RHW) messages to distant vehicles requires special mechanisms. In this case, the combination of direct communication between vehicles and the wide area coverage provided by cellular networks might be crucial not only for reducing the data transmission costs but also for improving the timeliness of ITS information. Moreover, the application of clustering and cluster head selection mechanisms among vehicles can increase the efficiency of hybrid vehicular and cellular communication networks. This paper introduces a novel cluster head selection technique for the distribution of RHW messages, and proposes an implementation of another legacy technique that was originally intended for mobile ad-hoc networks (MANETs). This paper evaluates the performance of these techniques by the means of computer simulations in two scenarios with distinct congestion and propagation conditions. The simulation results show the potential benefit of hybrid networks compared with pure cellular transmissions, especially, if the novel cluster head selection technique is used.

Versatile Transition for Multilayer Compact Devices in Empty Substrate Integrated Waveguide

  • Ballesteros, José A.
  • Fernández-Berlanga, Marcos D
  • Belenguer Martínez, Ángel
  • Esteban González, Héctor|||0000-0002-5936-658X
  • Boria Esbert, Vicente Enrique|||0000-0001-7150-9785
[EN] Empty substrate integrated waveguide (ESIW) devices can provide high quality and completely integrated devices, but they are usually larger than the same ones imple- mented with alternative technologies. One of the most extended strategies to compact electronic devices is the use of multilayer technology. Nevertheless, to perform multilayer devices in ESIW, a versatile and efficient transition between the guides in different layers is needed. Currently, only one multilayer device is known in this ESIW technology, which is a transition between a pair of guides built in contiguous layers that requires complex and nonstandard 3-D manufacturing processes. In this letter, a multilayer transition to connect a pair of guides separated by an arbitrary number of layers is successfully designed and experimentally validated without 3-D manufacturing processes. This novel and versatile transition opens the way to further develop multilayer compact devices in the ESIW technology such as compact filters., This work was supported by the Ministerio de Economia y Competitividad through Spanish Government under Project TEC2016-75934-C4-3-R and Project TEC2016-75934-C4-1-R. (Corresponding author: Angel Belenguer.)

Evolutionary Computation for Modelling Social Traits in Realistic Looking Synthetic Faces

  • Fuentes-Hurtado, Félix José
  • Diego-Mas, Jose Antonio|||0000-0002-3698-3411
  • Naranjo Ornedo, Valeriana|||0000-0002-0181-3412
  • Alcañiz Raya, Mariano Luis|||0000-0001-9207-0636
[EN] Human faces play a central role in our lives. Thanks to our behavioural capacity to perceive faces, how a face looks in a painting, a movie, or an advertisement can dramatically influence what we feel about them and what emotions are elicited. Facial information is processed by our brain in such a way that we immediately make judgements like attractiveness or masculinity or interpret personality traits or moods of other people. Due to the importance of appearance-driven judgements of faces, this has become a major focus not only for psychological research, but for neuroscientists, artists, engineers, and software developers. New technologies are now able to create realistic looking synthetic faces that are used in arts, online activities, advertisement, or movies. However, there is not a method to generate virtual faces that convey the desired sensations to the observers. In this work, we present a genetic algorithm based procedure to create realistic faces combining facial features in the adequate relative positions. A model of how observers will perceive a face based on its features' appearances and relative positions was developed and used as the fitness function of the algorithm. The model is able to predict 15 facial social traits related to aesthetic, moods, and personality. The proposed procedure was validated comparing its results with the opinion of human observers. This procedure is useful not only for creating characters with artistic purposes, but also for online activities, advertising, surgery, or criminology.

Legal measures to prevent and manage soil contamination and to increase food safety for consumer health: the case of Spain

  • Ramón Fernández, Francisca|||0000-0002-0936-8229
  • Lull, Cristina|||0000-0001-9270-2365
[EN] This article contains a brief overview of the European and Spanish environmental law framework for the prevention of soil contamination, for the management of contaminated soils and for consumers health protection in relation to agricultural crops. Some important aspects of the legislative framework for the prevention and management of soil contamination include recognising the possible risk to both human health and ecosystems that certain agricultural and industrial activities pose given the use of organic and inorganic chemical substances of a hazardous nature and pathogenic microorganisms. It is worth highlighting the milestone that many national constitutions include about the right to the environment. This right entails the obligation to protect it and to, therefore, protect soil from any degradation, including contamination. Legislation that protects soil from contamination and, consequently human health and ecosystems, is related mainly to agricultural activities (use of sewage sludge on farmlands, use of wastewater for irrigation, use of organic fertilisers and pesticides), and to industrial and commercial soil-contaminating activities. Consumer protection may be achieved through a legal system of environmental liability, specific measures to prevent contaminants entering soil, managing contaminated soils and a food traceability system. It is crucial to make the penalties for soil contamination offenses, and for violators of protective prohibitions, effective, proportionate and dissuasive. Global standards and guidelines on soil contamination could provide national legislative systems with substantive and procedural legal mechanisms to help prevent and manage soil contamination., This research was conducted as part of Project DER2015-65810-P, funded by the Spanish Ministry of Economy and Competitiveness, and by Project GVPROMETEOII2015-014, funded by the Regional Ministry of Culture, Education and Sport of the Valencian Autonomous Community, and by Projects HYDЯOSIL (CGL2011-28776-C02-02) and SILWAMED (CGL2014-58127-C3-2), funded by the Spanish Ministry of Science and Innovation and FEDER funds.

Contemporary Proximity Fiction

  • Alonso-López, Nàdia

GRC-Sensing: An Architecture to Measure Acoustic Pollution Based on Crowdsensing

  • Zamora-Mero, Willian Jesus
  • Vera, Elsa
  • Tavares De Araujo Cesariny Calafate, Carlos Miguel|||0000-0001-5729-3041
  • Cano, Juan-Carlos|||0000-0002-0038-0539
  • Manzoni, Pietro|||0000-0003-3753-0403
[EN] Noise pollution is an emerging and challenging problem of all large metropolitan areas, affecting the health of citizens in multiple ways. Therefore, obtaining a detailed and real-time map of noise in cities becomes of the utmost importance for authorities to take preventive measures. Until now, these measurements were limited to occasional sampling made by specialized companies, that mainly focus on major roads. In this paper, we propose an alternative approach to this problem based on crowdsensing. Our proposed architecture empowers participating citizens by allowing them to seamlessly, and based on their context, sample the noise in their surrounding environment. This allows us to provide a global and detailed view of noise levels around the city, including places traditionally not monitored due to poor accessibility, even while using their vehicles. In the paper, we detail how the different relevant issues in our architecture, i.e., smartphone calibration, measurement adequacy, server design, and client¿server interaction, were solved, and we have validated them in real scenarios to illustrate the potential of the solution achieved., This work was partially supported by Valencia's Traffic Management Department, by the "Ministerio de Economia y Competitividad, Programa Estatal de Investigacion, Desarrollo e Innovacion Orientada a los Retos de la Sociedad, Proyectos I + D + I 2014", Spain, under Grant TEC2014-52690-R, and the "Universidad Laica Eloy Alfaro de Manabi, and the Programa de Becas SENESCYT" de la Republica del Ecuador.

Impact of Temperature, Gum Arabic and Carboxymethyl Cellulose on Some Physical Properties of Spray-Dried Grapefruit

  • Gonzalez-Zamora, Freddy
  • Igual Ramo, Marta|||0000-0001-5128-5489
  • Camacho Vidal, Mª Mar|||0000-0002-2342-2105
  • Martínez Navarrete, Nuria|||0000-0001-8345-8495
[EN] Spray-dried fruit powder may be an interesting alternative for the purposes of promoting fruit consumption among consumers. The use of carrier agents is especially necessary for the production of spray-dried fruit powders. As they may affect some physical properties of the powder, it is important to adjust the amount at which they have to be added to the minimum in order to achieve the necessary effects. The final aim of the study was to identify the most suitable atomization temperature, as well as the optimal concentration of gum Arabic (GA) and carboxymethyl cellulose (CMC) to be used as carriers, in order to obtain grapefruit powder with the maximum dry matter yield (DMY) and porosity, the minimum water content and, simultaneously, with suitable color characteristics. The results of the study don¿t recommend the use of CMC and suggest that the best color, the one that corresponds to a free-flowing powder, corresponds to a very luminous one, low in chroma and with a hue that is much more yellow than reddish orange., The authors thank the Ministerio de Economia y Competitividad for the financial support given through the Project AGL 2012-39103. This mentioned received funding did not lead to any conflict of interests regarding the publication of this manuscript. The authors declare that there is no conflict of interest regarding the publication of this paper.

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