Search results for "Automobile"
showing 10 items of 257 documents
Energy Efficiency Optimization for Multi-cell Massive MIMO : Centralized and Distributed Power Allocation Algorithms
2021
This paper investigates the energy efficiency (EE) optimization in downlink multi-cell massive multiple-input multiple-output (MIMO). In our research, the statistical channel state information (CSI) is exploited to reduce the signaling overhead. To maximize the minimum EE among the neighbouring cells, we design the transmit covariance matrices for each base station (BS). Specifically, optimization schemes for this max-min EE problem are developed, in the centralized and distributed ways, respectively. To obtain the transmit covariance matrices, we first find out the closed-form optimal transmit eigenmatrices for the BS in each cell, and convert the original transmit covariance matrices desi…
Marrakair: une simulation participative pour observer les émissions atmosphériques du trafic routier en milieu urbain
2017
National audience; D’après l’Organisation Mondiale de la Santé (OMS), la pollution de l’air est le principal risque environnemental pour la santé dans le monde 1 (OMS, 2013). Àl’échelle locale, la pollution atmosphérique agit sur quelques kilomètres et se manifeste à proximité des sources de pollution comme la proximité aux sites industriels. En milieu urbain, le premier contributeur aux émissions de NOx, CO, ou PM10 dans l’atmosphère est le trafic routier (CITEPA, 2014). La pollution atmosphérique automobile (PAA) se caractérise en effet par l’émission de composés toxiques et cancérigènes directement émis par les moteurs. L’intensité des émissions est à relier au nombre de véhicules présen…
VLPZ: The Vehicular Location Privacy Zone
2016
International audience; One of the key challenges in the success of vehicular ad hoc networks (VANETs) is to consider the location privacy of drivers. Although, the pseudonym changing approach is suggested by standardization development organizations such as IEEE and ETSI, the development of an effective pseudonym changing strategy is still an open issue. The existing pseudonym changing strategies are either not effective to protect against the pseudonyms linking attacks or can have a negative impact on the VANETs’ applications. To address these issues, this paper proposes a new pseudonym changing strategy based on the Vehicular Location Privacy Zone (VLPZ), which is a roadside infrastructu…
From the Car Style Pregnancy towards the Brand Country Origin Recognition
2019
AbstractIn the modern automotive industry, a car's style clearly defines its brand. In the context of globalization, a question has recently emerged concerning the relationship between a country's culture and the car style of a particular brand. The style is one way to place car morphologies into a meaningful structure, called the “telling structure.” This research hypothesizes that a stylist tries to compress a car's form and make it a refined unicum that is streamlined with some inherent features, which express a brand's cultural aesthetics. Using the cognitive paradigm that an end user transforms explicit references into implic-it references and that the telling structure of a car's desi…
Optimal Integration of Hybrid Supercapacitor and IPT system for a Free Catenary Tramway
2017
The aim of the presented paper is the study of an optimal integration of Supercapacitor based storage system and Inductive Power Transfer system for the free-catenary operation of a tramway. The paper starts from the definition of the Inductive Power transfer pad system and proposed an optimal integration strategy for the correct size of on-board supercapacitors and the inductive energy transfer.
Validation d'un banc d'essais reproduisant les rafales de vent sur véhicule terrestre. Caractérisation de l'écoulement par TR-PIV
2011
National audience; Les phénomènes aérodynamiques instationnaires apparaissant autour de véhicules terrestres lors de rafales latérales, demeurent encore mal connus de par les difficultés, tant expérimentales que numériques, à reproduire fidèlement ces situations en laboratoire. L’ISAE a développé un banc d'essai, inspiré des travaux de Ryan et Dominy (Ryan et Dominy [2000]), dans lequel le déferlement de la rafale sur la maquette automobile est reproduit par un jet latéral mobile longitudinalement. L’écoulement généré par ce dispositif est validé PIV résolue en temps dans ce présent document. L’angle de dérapage obtenu lors d’une simulation de rafale présente une évolution temporelle proche…
Occupational health disparities among U.S. long-haul truck drivers: the influence of work organization and sleep on cardiovascular and metabolic dise…
2018
Objective The organization of work has undergone vast transformations over the past four decades in the United States and has had profound impacts on worker health and wellbeing. The profession of commercial truck driving is one of the best examples. Particularly for long-haul truck drivers, changes in work organization have led to disproportionately poor physiological, psychological, and sleep health outcomes. Methods The present study examined disparities in cardiometabolic disease risk among long-haul truck drivers and the general population, and the influence of work organization and sleep in generating these outcomes. Researchers collected survey data from 260 drivers, and blood assay …
The city under electrodes : from the measure to the evaluation of traffic air pollution : towards a multi-agent simulation of urban road traffic
2016
Based on surveys, traffic is constructed from assumptions about the relationship between origins and destinations. In order to rebuild a road traffic wich would be closer to observation and on a wider set of road sections, it appears interesting to use counting data from urban sensors : this is our starting point of view. The insertion of these in-situ dataset in the road traffic measurement provides the opportunity to experience the potential of sensors to estimate Traffic Air Pollution (TAP) levels at the intraurban scale. However, this requires to change the nature of these estimation, here through the construction of a model of multi-agents simulation, in order to extract more informati…
Acceptance of truck platooning by professional drivers on German highways. A mixed methods approach.
2020
Abstract Truck platoon driving is a current branch of automated driving, which has the potential to radically change the work routine of professional drivers. In a platoon system, one truck (semi-)automatically follows a lead truck with a reduced distance, which produces significant savings in fuel and enables better traffic flow. In a current application of truck platoon driving, the following vehicle operates at level-2 automation. Thus, the driver of the following truck merely has to supervise the semi-automated system, which takes over steering and speed control when engaged. Level-2 truck platoon driving had not been tested with professional drivers in real traffic before. We hypothesi…
Increase in rear-end collision risk by acute stress-induced fatigue in on-road truck driving.
2021
Increasing road crashes related to occupational drivers’ deteriorating health has become a social problem. To prevent road crashes, warnings and predictions of increased crash risk based on drivers’ conditions are important. However, in on-road driving, the relationship between drivers’ physiological condition and crash risk remains unclear due to difficulties in the simultaneous measurement of both. This study aimed to elucidate the relationship between drivers’ physiological condition assessed by autonomic nerve function (ANF) and an indicator of rear-end collision risk in on-road driving. Data from 20 male truck drivers (mean ± SD, 49.0±8.2 years; range, 35–63 years) were analyzed. Over …