Search results for "AUTOMOBILE"
showing 10 items of 257 documents
Sleep Apnea, Sleepiness, and Driving Risk
2019
Obstructive sleep apnea is associated with excessive daytime sleepiness in about 50% of cases, and with increased risk of driving accidents. Treatment with continuous positive airway pressure effectively decreases such risk, but compliance with continuous positive airway pressure treatment is often suboptimal. According to the European Union Directive on driving risk, retention of a driving license in patients with obstructive sleep apnea requires assessment of sleepiness and adherence to continuous positive airway pressure treatment, but there remains uncertainty on the optimal methods to assess sleepiness on a large scale.
Simulation-Based Analysis of "What-If" Scenarios with Connected and Automated Vehicles Navigating Roundabouts.
2022
Despite the potential of connected and automated vehicles (CAVs), there are still many open questions on how road capacity can be influenced and what methods can be used to assess its expected benefits in the progressive transition towards fully cooperative driving. This paper contributes to a better understanding of the benefits of CAV technologies by investigating mobility-related issues of automated vehicles operating with a cooperative adaptive cruise control system on roundabout efficiency using microscopic traffic simulation. The availability of the adjustment factors for CAVs provided by the 2022 Highway Capacity Manual allowed to adjust the entry capacity equations to reflect the pr…
Multitasking in Driving as Optimal Adaptation Under Uncertainty
2021
Objective The objective was to better understand how people adapt multitasking behavior when circumstances in driving change and how safe versus unsafe behaviors emerge. Background Multitasking strategies in driving adapt to changes in the task environment, but the cognitive mechanisms of this adaptation are not well known. Missing is a unifying account to explain the joint contribution of task constraints, goals, cognitive capabilities, and beliefs about the driving environment. Method We model the driver’s decision to deploy visual attention as a stochastic sequential decision-making problem and propose hierarchical reinforcement learning as a computationally tractable solution to it. The…
Protocol for developing a mental imagery intervention: a randomised controlled trial testing a novel implementation imagery e-health intervention to …
2019
IntroductionDrowning due to driving into floodwater accounts for a significant proportion of all deaths by drowning. Despite awareness campaigns such as 'If it's flooded, forget it', people continue to drive into floodwater. This causes loss of life, risk to rescuers and damage to vehicles. The aim of this study was to develop and evaluate an online e-health intervention to promote safe driving behaviour during flood events.Methods and analysisThe study will use a 2×3 randomised controlled trial in which participants are randomised into one of two conditions: (1) education about the risks of driving into floodwater or (2) education about the risks of driving into floodwater plus a theory-ba…
Le travail auto-biographique : Quand une voiture ancienne permet de négocier un héritage narratif
2022
Cet article propose d'expliciter la manière dont les voitures anciennes peuvent constituer un outil du travail narratif individuel. À partir de deux études de cas particulièrement typiques, il s'attarde à démontrer que les individus contemporains produisent des récits d'eux-mêmes, qu'ils aspirent à leur reconnaissance, et que les objets matériels participent de ce travail de l'héritage identitaire. Sommaire 1) Le lieu de mémoire contre l'objet-souvenir 2) Fabriquer sa filiation et se construire un héritage 3) D'une l'origine modeste à l'ascension sociale : l'objet comme porte-parole 4) Une transaction relationnelle au sein des cercles d'initiés Conclusion
Multi-Resource Management for Multi-Tier Space Information Networks: A Cooperative Game
2019
With the drastic increase of space information network (SIN) traffic and the diversity of network traffic types, the optimal allocation of the scarce network resources is of great significance for optimizing the SIN system capability. In this paper, we propose a multi-resource management method for multi-tier SIN using the cooperative Nash bargaining solution. Since the original problem is a non-convex problem, we firstly make logarithmic transition, and then find a tightest lower bound function to convert the initial problem into a convex one. In order to carry out the optimal bandwidth and power allocation in SIN, we construct a joint bandwidth and power allocation (JBPA) algorithm. Simul…
A Comprehensive Survey on Cooperative Relaying and Jamming Strategies for Physical Layer Security
2019
Physical layer security (PLS) has been extensively explored as an alternative to conventional cryptographic schemes for securing wireless links. Many studies have shown that the cooperation between the legitimate nodes of a network can significantly enhance their secret communications performance, relative to the noncooperative case. Motivated by the importance of this class of PLS systems, this paper provides a comprehensive survey of the recent works on cooperative relaying and jamming techniques for securing wireless transmissions against eavesdropping nodes, which attempt to intercept the transmissions. First, it provides a in-depth overview of various secure relaying strategies and sch…
Robust Transmit Beamforming for Underlay D2D Communications on Multiple Channels
2020
Underlay device-to-device (D2D) communications lead to improvement in spectral efficiency by simultaneously allowing direct communication between the users and the existing cellular transmission. However, most works in resource allocation for D2D communication have considered single antenna transmission and with a focus on perfect channel state information (CSI). This work formulates a robust transmit beamforming design problem for maximizing the aggregate rate of all D2D pairs and cellular users (CUs). Assuming complex Gaussian distributed CSI error, our formulation guarantees probabilistically a signal to interference plus noise ratio (SINR) above a specified threshold. In addition, we al…
Stochastic Collaborative Beamforming in Wireless Sensor Networks
2018
Wireless Sensor Networks (WSNs) are composed of spatially distributed autonomous sensor devices, named motes. These devices are constituted by a microcontroller, sensors, and they have the ability to communicate in the ISM frequency band using the IEEE 802.15.4 standard. They have their own power supply, AA or AAA batteries, processing unit, sensors and wireless communications. Usually, the motes exchange packets using a multihop routing, and the maximum communication distance emitter-receiver is around 100m. At least one mote acts as a gateway, and the data gathered by the sensors of each mote have to be sent to this mote that is named sink or Base Station (BS). In a WSN the BS is within t…
On the Statistical Properties of Capacity Outage Intervals in OSTBC-MIMO Rayleigh Fading Channels
2016
This paper deals mainly with the study of the asymptotic probability density functions (PDFs) of the outage durations of the instantaneous capacity of orthogonal space-time block code (OSTBC) multiple-input multiple-output (MIMO) systems over Rayleigh channels. Drawing upon known statistical properties for the asymptotic behavior of chi-squared processes at low levels, we provide approximate solutions for the PDF, the cumulative distribution function (CDF), and the $k$ th-order moments of the outage intervals of the underlying capacity processes. Then, as an application of the derived PDF, the performance assessment of capacity simulators is reported. Following this, we introduce the newly …