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See detailTraffic Routing in Urban Environments: the Impact of Partial Information
Codeca, Lara UL; Frank, Raphaël UL; Engel, Thomas UL

in Proceedings of 17th Internatonal IEEE Conference on Intelligent Transportation Systems (2014, October)

There are many studies concerning the problem of traffic congestion in cities. One of the best accepted solutions to relieving congestion involves optimization of resources already available, by means of ... [more ▼]

There are many studies concerning the problem of traffic congestion in cities. One of the best accepted solutions to relieving congestion involves optimization of resources already available, by means of balancing traffic flows to minimize travel delays. To achieve this optimization, it is necessary to collect and process Floating Car Data (FCD) from vehicles. In this paper we evaluate the repercussions of partial information on the overall traffic view, and consequently on the outcome of the optimization. Our study focuses on the role of the user participation rate and the availability of Road Side Units to collect the FCD. By means of simulation we quantify the impact of partially-available information on the computation of route optimization, and how it impedes traffic flows. Our results show that even minor uncertainties can significantly impact routing strategies and lead to deterioration in the overall traffic situation. [less ▲]

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See detailBluetooth Low Energy: An Alternative Technology for VANET Applications
Frank, Raphaël UL; Bronzi, Walter UL; Castignani, German UL et al

in Proceedings of the 11th IEEE/IFIP Annual Conference on Wireless On-demand Network Systems and Services (2014, April)

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See detailImproving Traffic in Urban Environments
Codeca, Lara UL; Frank, Raphaël UL; Engel, Thomas UL

Report (2014)

The vehicular traffic in the cities is increasing every year. The road infrastructure in many metropolitan areas is not able to sustain the rush-hour traffic demand and the extension of the road network ... [more ▼]

The vehicular traffic in the cities is increasing every year. The road infrastructure in many metropolitan areas is not able to sustain the rush-hour traffic demand and the extension of the road network cannot easily be done. There are some solution proposed to improve the traffic situation, among them, the optimization of the resources already available by means of collecting real time Floating Car Data (FCD) from the vehicles and use them to suggest dynamic routes in order to minimize travel delays. The centralized infrastructure able to achieve this goal has already been presented in ”Improving Traffic in Urban Environments applying the Wardrop Equilibrium” (Codeca, L. et al., 2013). In this extended abstract we present the decentralized version of the system and the preliminary results of its evaluation. [less ▲]

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See detailCollaborative Traffic Sensing: A Case Study of a Mobile Phone Based Traffic Management System
Frank, Raphaël UL; Weitz, Hervé UL; Castignani, German UL et al

in Proceedings of the 11th IEEE Consumer Communications and Networking Conference (CCNC'14) (2014, January 10)

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See detailA Cooperative Advanced Driver Assistance System to Mitigate Vehicular Traffic Shock Waves
Forster, Markus UL; Frank, Raphaël UL; Gerla, Mario et al

in IEEE INFOCOM 2014 - IEEE Conference on Computer Communications (2014)

We address the problem of shock wave formation in uncoordinated highway traffic. First, we identify the combination of heavy traffic and small traffic perturbations or unexpected driver actions as the ... [more ▼]

We address the problem of shock wave formation in uncoordinated highway traffic. First, we identify the combination of heavy traffic and small traffic perturbations or unexpected driver actions as the main causes of highway traffic jams. Then we introduce a novel distributed communication protocol that enables us to eliminate upstream shock wave formation even with low system penetration rates. Based on traffic information ahead, we propose a Cooperative Advanced Driver Assistance System (CADAS) that recommends non-intuitive velocity reductions in order to redistribute traffic more uniformly thereby eliminating traffic peaks. Simulation results show that CADAS significantly increases the average velocity and therewith reduces the overall travel time and avoids unnecessary slowdowns. [less ▲]

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See detailA novel Eco-Driving Application to Reduce Energy Consumption of Electric Vehicles
Frank, Raphaël UL; Castignani, German UL; Schmitz, Raoul et al

in Proceedings of the 2nd International Conference on Connected Vehicles & Expo (ICCVE 2013) (2013, December)

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See detailA Study of Urban IEEE 802.11 Hotspot Networks: Towards a Community Access Network
Castignani, German UL; Monetti, Juan; Montavont, Nicolas et al

in A Study of Urban IEEE 802.11 Hotspot Networks: Towards a Community Access Network (2013, November 13)

With the increasing demand for faster data connectivity, different wireless technologies have been deployed in the last decade, creating a heterogeneous wireless environment. Such wireless diversity is ... [more ▼]

With the increasing demand for faster data connectivity, different wireless technologies have been deployed in the last decade, creating a heterogeneous wireless environment. Such wireless diversity is mainly composed of 2G/3G/4G cellular base stations, IEEE 802.11 hotspots and Community Networks. Previous work suggests that the increasing popularity of IEEE 802.11 networks would mitigate the overloading of current operator-based cellular deployments. However, the unpredictable characteristics of IEEE 802.11 deployments and its loose coupling to cellular architectures limit its user performance in terms of throughput and mobility capacity. In this paper, we describe an evaluation study of a commercial-grade hotspot network in the city of Luxembourg, namely HOTCITY. Through a set of experiments, we provide a characterization of the hotspot network and give a set of performance indicators. Finally, we evaluate hotspot networks' potential to support cellular offloading through the integration of outdoor hotspots and private access points deployed indoors in a single Community Network. [less ▲]

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See detailImproving Traffic in Urban Environments applying the Wardrop Equilibrium
Codeca, Lara UL; Frank, Raphaël UL; Engel, Thomas UL

in Improving Traffic in Urban Environments applying the Wardrop Equilibrium (2013, October 07)

Over the last few years vehicular traffic density has continuously increased and it is likely that the traffic demand will further increase in the future. In many metropolitan areas the road ... [more ▼]

Over the last few years vehicular traffic density has continuously increased and it is likely that the traffic demand will further increase in the future. In many metropolitan areas the road infrastructure is no longer able to handle the peak traffic demand and the existing road network cannot be easily extended. The best way to improve the traffic situation is to optimise the resources available in the transportation network and to coordinate the traffic demand. The approach that we propose in this paper makes use of a collaborative traffic coordination protocol which collects real-time Floating Car Data (FCD) directly from participating vehicles and suggests dynamic routes in order to minimize travel delay. Information such as speed, position and direction is sent to one or more Traffic Coordination Points (TCPs) where it is aggregated to obtain a global picture of the traffic conditions in real-time. Based on this data, we continuously compute the route that minimizes the travel time to a given destination by applying Wardrop’s first principle of equilibrium. Our results show that, by coordinating the vehicles, we are able to better distribute the overall traffic demand throughout the transportation network, reducing the average travel times and accommodating more vehicles. [less ▲]

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See detailAn Evaluation Study of Driver Profiling Fuzzy Algorithms using Smartphones
Castignani, German UL; Frank, Raphaël UL; Engel, Thomas UL

in An Evaluation Study of Driver Profiling Fuzzy Algorithms using Smartphones (2013, October)

Profiling driving behavior has become a relevant aspect in fleet management, automotive insurance and eco-driving. Detecting inefficient or aggressive drivers can help reducing fleet degradation ... [more ▼]

Profiling driving behavior has become a relevant aspect in fleet management, automotive insurance and eco-driving. Detecting inefficient or aggressive drivers can help reducing fleet degradation, insurance policy cost and fuel consumption. In this paper, we present a Fuzzy-Logic based driver scoring mechanism that uses smartphone sensing data, including accelerometers and GPS. In order to evaluate the proposed mechanism, we have collected traces from a testbed consisting in 20 vehicles equipped with an Android sensing application we have developed to this end. The results show that the proposed sensing variables using smartphones can be merged to provide each driver with a single score. [less ▲]

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See detailDriver Behavior Profiling using Smartphones
Castignani, German UL; Frank, Raphaël UL; Engel, Thomas UL

in Driver Behavior Profiling using Smartphones (2013, October)

The proliferation of smartphones and mobile devices embedding different types of sensors sets up a prodigious and distributed sensing platform. In particular, in the last years there has been an ... [more ▼]

The proliferation of smartphones and mobile devices embedding different types of sensors sets up a prodigious and distributed sensing platform. In particular, in the last years there has been an increasing necessity to monitor drivers to identify bad driving habits in order to optimize fuel consumption, to reduce CO2 emissions or, indeed, to design new reliable and fair pricing schemes for the insurance market. In this paper, we analyze the driver sensing capacity of smartphones. We propose a mobile tool that makes use of the most common sensors embedded in current smartphones and implement a Fuzzy Inference System that scores the overall driving behavior by combining different fuzzy sensing data. [less ▲]

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See detailA Study on Highway Traffic Flow Optimization using Partial Velocity Synchronization
Forster, Markus UL; Frank, Raphaël UL; Engel, Thomas UL

in Proceedings of the 1st GI/ITG KuVS Fachgespräch Inter-Vehicle Communication (FG-IVC 2013) Technical Report CCS-2013-01 (2013)

In this paper we present a study of highway traffic flow optimization using Partial Velocity Synchronization (PVS). PVS is a Cellular Automaton (CA) model that is extended by a communication layer ... [more ▼]

In this paper we present a study of highway traffic flow optimization using Partial Velocity Synchronization (PVS). PVS is a Cellular Automaton (CA) model that is extended by a communication layer providing the ability to exchange relevant information between vehicles. We show that it is possible to enhance traffic flow on highways significantly with a small number of velocity recommendations computed from the traffic conditions ahead. Furthermore we show that only a limited number of hops in an information chain is necessary to reschedule the vehicles on a given highway segment to avoid the formation of shockwaves. Our results show that traffic flow will be increased while travel time and emissions will be reduced dramatically. [less ▲]

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See detailLuxTraffic: A Collaborative Traffic Sensing System
Kovacheva, Aleksandrina; Frank, Raphaël UL; Engel, Thomas UL

in Proceedings of the 19th IEEE Workshop on Local & Metropolitan Area Networks (LANMAN'13) (2013)

Detailed reference viewed: 208 (7 UL)
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See detailEnergy-Efficient Rate-Adaptive Passive Traffic Sensing using Smartphones
Frank, Raphaël UL; Melakessou, Foued UL; Castignani, German UL

in Proceedings of the 12th Annual Mediterranean Ad Hoc Networking Workshop (MedHocNet 2013) (2013)

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See detailTowards Collaborative Traffic Sensing using Mobile Phones
Frank, Raphaël UL; Mouton, Maximilien UL; Engel, Thomas UL

in Proceedings of the IEEE Vehicular Networking Conference 2012 (2012)

Participatory mobile sensing applications are becoming increasingly popular. The growing population of privately-held mobile smartphones enables a plethora of new services. One of the most promising ... [more ▼]

Participatory mobile sensing applications are becoming increasingly popular. The growing population of privately-held mobile smartphones enables a plethora of new services. One of the most promising application areas is collaborative traffic sensing. Here, smartphones are used as mobile sensors to collect and share relevant location information in order to reconstruct a global picture of the traffic situation in a monitored area. There are several challenges that need to be addressed in order to provide an efficient and ubiquitous service. In this talk we present how low-cost mobile smartphones can be used for such services without compromising the everyday usage of the device. We first test several sensing policies and evaluate how they affect location accuracy and battery life. We then perform a penetration rate study to identify the proportion of participants required to provide good service by varying several parameters. The outcome shows that if configured correctly, smartphones can be used as accurate mobile traffic sensors providing important information even at low penetration rates. [less ▲]

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See detailImproving Highway Traffic through Partial Velocity Synchronization
Forster, Markus UL; Frank, Raphaël UL; Gerla, Mario et al

in Proceedings of the IEEE Global Communications Conference 2012 (2012)

In this paper we address the problem of uncoor- dinated highway traffic. We first identify the main causes of the capacity drop, namely high traffic demand and inadequate driver reaction. In the past ... [more ▼]

In this paper we address the problem of uncoor- dinated highway traffic. We first identify the main causes of the capacity drop, namely high traffic demand and inadequate driver reaction. In the past, traffic and user behavior have been accurately described by cellular automata (CA) models. In this paper we extend the CA model to deal with highway traffic fluctuations and jams. Specifically, the model incorporates the communication layer between vehicles. The model thus enables us to study the impact of inter-vehicular communications and in particular the delivery of critical and timely upstream traffic information on driver reaction. Based on the newly-available traffic metrics, we propose an Advanced Driver Assistance System (ADAS) that suggests non-intuitive speed reduction in order to avoid the formation of so-called phantom jams. The results show that using such a system considerably increases the overall traffic flow, reduces travel time and avoids unnecessary slow-downs. [less ▲]

Detailed reference viewed: 180 (7 UL)
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See detailA Survey on the Performance of Commercial Mobile Access Networks
Frank, Raphaël UL; Forster, Markus UL; Mario, Gerla et al

Report (2012)

Detailed reference viewed: 117 (6 UL)