316 research outputs found

    Performance tuning of a smartphone-based overtaking assistant

    Get PDF
    ITS solutions suffer from the slow pace of adoption by manufacturers despite the interest shown by both consumers and industry. Our goal is to develop ITS applications using already available technologies to make them affordable, quick to deploy, and easy to adopt. In this paper we introduce EYES, an overtaking assistance solution that provides drivers with a real-time video feed from the vehicle located just in front. Our application thus provides a better view of the road ahead, and of any vehicles travelling in the opposite direction, being especially useful when the front view of the driver is blocked by large vehicles. We evaluated our application using the MJPEG video encoding format, and have determined the most effective resolution and JPEG quality choice for our case. Experimental results from the tests performed with the application in both indoor and outdoor scenarios, allow us to be optimistic about the effectiveness and applicability of smartphones in providing overtaking assistance based on video streaming in vehicular networks

    A novel on-board Unit to accelerate the penetration of ITS services

    Get PDF
    In-vehicle connectivity has experienced a big expansion in recent years. Car manufacturers have mainly proposed OBU-based solutions, but these solutions do not take full advantage of the opportunities of inter-vehicle peer-to-peer communications. In this paper we introduce GRCBox, a novel architecture that allows OEM user-devices to directly communicate when located in neighboring vehicles. In this paper we also describe EYES, an application we developed to illustrate the type of novel applications that can be implemented on top of the GRCBox. EYES is an ITS overtaking assistance system that provides the driver with real-time video fed from the vehicle located in front. Finally, we evaluated the GRCbox and the EYES application and showed that, for device-to-device communication, the performance of the GRCBox architecture is comparable to an infrastructure network, introducing a negligible impact

    EYES : a novel overtaking assistance system for vehicular networks

    Get PDF
    Developments in the ITS area are received with great expectation by both consumers and industry. Despite their huge potential benefits, ITS solutions suffer from the slow pace of adoption by manufacturers. In this paper we propose EYES, an ITS system that aims at helping drivers in overtaking. The system autonomously creates a network of the devices running EYES, and provides drivers with a video feed from the vehicle located just ahead, thus presenting a better view of any vehicles coming from the opposite direction and the road ahead. This is specially useful when the front view of the driver is blocked by large vehicles, and thus the decision whether to overtake can be taken based on the visuals provided by the application. We have validated EYES, the proposed overtaking assistance system, in both indoor and realistic scenarios involving vehicular network, and preliminary results allow being optimistic about its effectiveness and applicability

    Determining the relative position of vehicles considering bidirectional traffic scenarios in VANETS

    Get PDF
    Researchers pertaining to both academia and industry have shown strong interest in developing and improving the existing critical ITS solutions. In some of the existing solutions, specially the ones that aim at providing context aware services, the knowledge of relative positioning of one node by other nodes becomes crucial. In this paper we explore, apart from the conventional use of GPS data, the applicability of image processing to aid in determining the relative positions of nodes in a vehicular network. Experiments conducted show that both the use of location information and image processing works well and can be deployed depending on the requirement of the application. Our experiments show that the results that used location information were affected by GPS errors, while the use of image processing, although producing more accurate results, require significantly more processing power

    Messiah: An ITS drive safety application

    Get PDF
    This article describes a novel safety application based on the open source navigation software OsmAnd, which runs on the Android platform. The application offers vehicles with "smart navigation", and maintains a network of the vehicles that use our application. The process of network creation and maintenance is important as our application enables vehicles to communicate with one another to exchange useful information. The main function of the application is to inform vehicles of relevant vehicles approaching, termed as "administrative vehicles" in this article, and include ambulances, police cars and fire brigades. Based on the received information, our application notifies the driver, who can now take navigation decisions based on it. While developing the application, problems were found when attempting to create an Ad-hoc network. A solution to the problem of managing the Ad-hoc network has been proposed and is under development

    Evaluación de mapas conceptuales en asignaturas de informática utilizando métricas objetivas

    Get PDF
    Los Mapas Conceptuales han sido utilizados desde hace bastante tiempo y sus principios han dado lugar a diferentes teorías de aprendizaje. Cuando éstos son utilizados como una herramienta para evaluar el aprendizaje, su utilización reporta importante beneficios, debido a que permiten que el alumno exprese de una forma natural su árbol mental de conceptos asimilados. Sin embargo, el proceso de evaluación de los mismos conlleva un importante grado de subjetividad, el cual debería ser reducido para promover su utilización. En este trabajo, proponemos separar el proceso de evaluación de mapas conceptuales, siguiendo los mismos pasos utilizados para la creación de los mismos, utilizando además métricas objetivas para dar una puntuación a cada uno de los pasos utilizados en su elaboración. Se propone una fórmula que combina las puntuaciones intermedias para obtener la puntuación final del mapa conceptual. La técnica de evaluación propuesta ha sido validada utilizando diferentes mapas conceptuales de estudiantes que han sido evaluados utilizando o no la técnica aquí propuesta. Los resultados muestran que la técnica propuesta permite reducir la alta variabilidad de las evaluaciones realizadas por diferentes instructores, permitiendo además reducir considerablemente el esfuerzo necesario en el proceso de evaluación.Peer Reviewe

    Analysis and design of efficient techniques for video transmission in IEEE 802.11 wireless ad hoc networks

    Full text link
    [EN] Wireless mobile ad ho networks, also known as MANETs, are omposed by independent mobile stations that ommuni ate without requiring any sort of infrastru ture for support. These networks are hara terized by variable bandwidth values and frequent path breaks, whi h are due to hannel noise, interferen e between stations and mobility. Su h fa tors require significant adaptation apabilites at different levels of the proto ol suites employed, enabling stations to qui kly respond to fast- hanging network onditions. Resear h on the most adequate proto- ols for the physi al, MAC and routing layers is still on-going, though some basi onsensus has already been rea hed and several testbeds have been setup around the world. To deploy real-time multimedia servi es, namely voi e and video, on top of su h an unreliable network environment is a very hallenging task. In this thesis we propose to a hieve that goal starting from urrently available Wi-Fi te hnology, and gradually finding the most adequate enhan ements to ea h proto ol layer of interest; we then ombine these enhan ements until we a hieve a omplete QoS framework for ad ho networks. By using urrently available te hnology we assure that the proposal of this thesis has an inherent high-level of appli ability on real life environments. Sin e our working field fo uses on video transmission over wireless ad ho networks, we will show how it is possible to support several QoS- onstrained video streams in MANET environments hara terized by moderate to high mobility levels, and by a significant amount of best efort traffic[ES] Las redes inalámbricas ad hoc, también conocidas como redes MANET, están compuestas por un conjunto de estaciones móviles independientes capaces de omunicarse entre sí sin necesidad de ningún tipo de infraestructura común de comunicaciones. Estas redes se caracterizan por tener un ancho de banda variable y pérdidas frecuentes de ruta que se pueden atribuir al ruido del anal inalámbrico, a la interferencia entre las estaciones móviles o bien a la movilidad de las estaciones. Dichos factores requieren una gran capacidad de adaptación en las diferentes capas de la arquitectura de protocolos, permitiendo a una estación responder rápidamente a posibles cambios bruscos en las condiciones de la red. A pesar de que aún se están realizando trabajos de investigación en bus a de los protocolos más adecuados para las capas físicas, a eso al medio (MAC) y encaminamiento, ha sido posible llegar a un nivel básico de consenso, lo cual ha permitido el despliegue de plataformas y entornos aplicados que utilizan tecnología de red MANET. Ofrecer servicios multimedia, como voz y vídeo, en redes con tan poca habilidad es un desafío importante. En esta tesis nos proponemos alcanzar este objetivo partiendo de la tecnología Wi-Fi actualmente disponible, encontrando de forma paulatina las mejoras más importantes en las diferentes capas de la arquitectura de red, para llegar, finalmente, a una solución integrada capaz de ofrecer calidad de servicio (QoS) en las redes MANET. Al utilizar la tecnología que disponemos actualmente nos aseguramos que las propuestas de esta tesis tengan un alto grado de aplicabilidad en entornos reales. Ya que la línea de trabajo de la tesis está aplicada a la transmisión de vídeo en redes MANET, demostraremos que es posible ofrecer calidad de servicio a varios flujos de vídeo en una red MANET caracterizada por altos grados de movilidad en sus nodos y un nivel significativo de tráfico o de tipo best effortTavares De Araujo Cesariny Calafate, CM. (2006). Analysis and design of efficient techniques for video transmission in IEEE 802.11 wireless ad hoc networks [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/135282TESI

    On the Use of Mobile Sensors for Estimating City-Wide Pollution Levels

    Full text link
    ©2015 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Obtaining detailed pollution maps for urban environments is an effort that is gathering much interest by allowing to better regulate traffic and protect citizens from hazardous conditions. However, the scarcity of pollution sensors prevents obtaining the desired degree of detail, requiring alternative solutions to be deployed. In this paper we explore the concept of mobile pollution sensing by studying the feasibility of equipping buses with ozone measurement hardware to estimate ozone patterns for the city of Compiègne. Overall, we achieve accurate estimations, with error values typically ranging from 2% to 10%. Compared to solutions based on deploying static sensors on the different bus stops available, we find that the proposed mobile sensing approach is able to provide a degree of accuracy comparable to deploying tens of static sensors, substantially reducing costs and management.This work was carried out and funded in the framework of the Labex MSZT. It was supported by the French Government, through the program "Investments for the future” managed by the National Agency for Research (Reference ANR-11-IDEX-0004-02). This work was partially funded by the Celtic Plus CoMoSeF project "Cooperative mobility for the services of the future". The authors thank the Agglomération de la Région de Compiégne (ARC).Tavares De Araujo Cesariny Calafate, CM.; Ducourthial, B. (2015). On the Use of Mobile Sensors for Estimating City-Wide Pollution Levels. IEEE. doi:10.1109/IWCMC.2015.7289093

    Assessing the limits of centralized unmanned aerial vehicle conflict management in U-Space

    Get PDF
    There is an important growth of unmanned aerial vehicles (UAVs) performing planned missions in urban environments, which poses significant challenges to the research community. The possibility of collisions represents a critical challenge. UAVs can suffer collisions due to different causes external or internal to their flight plans. In this context, dynamic geo-fencing is a useful approach, whereby each UAV is able to provide a prediction of its future positions within a limited time. These predictions could be used to detect conflicts, allowing to dynamically modify the flight plans so as to avoid imminent collisions. In this work, a conflict detection algorithm/method is proposed, implemented and tested on a central server performing real-time conflict analysis for a large number of UAVs flying in the aerial space of a city (U-Space). The architecture assumes that UAVs send their future locations to a traffic controller. This controller compares the predicted positions of nearby vehicles to detect possible conflicts. The results of this work demonstrate the feasibility of the proposed conflict detection algorithm and its interest to improve the security and efficiency in U-Space environments. The server is able to track thousands of UAVs in real time with a conflict anticipation around 11 s.This work is derived from the following R&D projects: PID2021-122580NB-I00 and RTI2018-098156-B-C52, funded by MCIN/AEI/10.13039/501100011033, “ERDF A way of making Europe”, and SBPLY/19/180501/000159, funded by the Junta de Comunidades de Castilla-La Mancha (JCCM) and the EU through the European Regional Development Fund (ERDF-FEDER)
    corecore