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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
511

Transformational Leadership and Safe Driving Performance in the U.S. Electric Utility Industry

Joseph, Mackington 01 January 2015 (has links)
Transformational leadership (TL) has been found popular in many industries in the United States and abroad for the perceived transformational leaders' effectiveness in improving occupational safety. There is a lack of empirical evidence to confirm these claims for safe occupational driving. This phenomenological study attempted to fill this knowledge gap in the electric utility industry where employees must drive in all weather conditions to restore power to customers. The conceptual framework for the study was based on leadership and motivation theories of Burns and Maslow. The research questions explored the influence of (a) TL on safe driving performance improvement in organizations and (b) emotional intelligence (EI) on leaders' efficiency to improve safe driving performance in organizations. These questions were addressed using a 14-item in-depth, open-ended interview questionnaire by a convenience sample of 18 management and 12 union-represented personnel drawn from 5 U.S. electric utility companies using the snowball method. Data were analyzed using NVivo 10 software and were interpreted using the methodological framework of Leedy and Ormrod, and Maxwell. The findings suggested that (a) TL influenced safe driving performance through these leaders' idealized influence, inspirational motivation, and intellectual stimulation; and (b) EI ineffectively and unreliably influenced safe driving improvement, but it improved organizational trust through the leaders' empathy and drivers' empowerment. Individualized consideration, while acknowledged as desirable, was least important and was widely lacking. The implications for positive social change include promoting TL style in other industries, raising employees' commitment and contribution to safe driving performance improvement, and improving organizational trust as well as public safety.
512

Ingénierie cognitive pour l'aide à la conduite automobile de la personne âgée : analyse et modélisation de l'activité de conduite en situation naturelle pour la conception de fonctions de monitorage / Cognitive engineering for elderly driver assistance : analysis and modelling of the driving activity in ecological situation’s, for the design of monitoring functions

Paris, Jean-Christophe 19 December 2014 (has links)
Cette thèse en Cognitique se focalise sur la « Conception Centrée sur l'Humain » (Human Centred Design) de futures assistances à la conduite automobile, adaptées aux conducteurs âgés (ou Elderly Adapted Driver Assistance Systems).Pour ce faire, la démarche proposée repose sur une approche et une méthodologie pluridisciplinaire. Sur le plan ergonomique, il s'agit de mieux connaître les spécificitésde la population des conducteurs âgés, dans le but d'identifier des difficultés et des besoins en assistance. A cette fin, 76 conducteurs âgés (de 70 à 87 ans) ont conduitun véhicule instrumenté, immergé dans le trafic. Le corpus de données comporte2100 kilomètres de conduite et 1400 situations de conduite autoévaluées par lesconducteurs, complétés par 6 Focus Group (30 conducteurs âgés).Le second volet, relevant d'une démarche d'Ingénierie Cognitive, vise à concevoir et développer des fonctions de « monitorage » à partir du corpus de données. L'objectif est de disposer de modèles et de fonctions d'analyse temps-réel capables (1) de superviser l'activité de conduite des conducteurs âgés (2) en regard du contexte ou des risques situationnels, afin de (3) diagnostiquer des difficultés ou erreurs de conduite, à des fins d’adaptativité des assistances. Des fonctions de monitorage en lien avec les contrôles de base du véhicule (gestion de la vitesse, positionnement dans la voie et la gestion de l'espace inter-véhiculaire avant) sont développées. Sur cette base, des fonctions de monitorage plus intégrées pour l'aide aux franchissements d'intersections (Tourne-à-Gauche) et l'assistance à l'insertion sur voies rapides (et au changement de voie) sont également proposées. / This thesis in Cognitics presents a Human Centered Design approach for thedevelopment of future driving assistance systems dedicated to elderly drivers orElderly Adapted Driver Assistance Systems (E-ADAS).To do so, this work relies on a multi-disciplinary approach for data collection andanalysis. Regarding Ergonomics, the aim is to better understand the specificrequirements of this population in order to identify their actual difficulties and actualneeds of assistance. In this frame, 76 drivers (aged from 70 to 87 years old) took partto an on-the-road experiment, driving an instrumented car. The dataset includes2100 km of ecological driving data and 1400 auto-evaluated driving situations,completed by 6 Focus Groups (involving 30 elderly drivers).The second part of this research, relying on Cognitive Engineering, explores thedesign and implementation of monitoring functions based on the aforementioneddataset. The objective is to have real-time models and analytical functions, able to:(1) supervise the driving activity as realized by an elderly driver, (2) taking in toconsideration the driving context or situational risks (3) in order to detect difficulties ordriving errors. Beyond this thesis, these diagnostics will have to be integrated inassistive systems to better adapt their support to the specific needs of elderly drivers.Specific monitoring functions related to basic vehicle control (speed management,lane positioning and headway regulation) are presented. Based on these results,integrated monitoring functions for intersection crossings in Left-Turn manoeuver,highway merging assistance, and, more broadly, lane change assistance areintroduced.
513

Eruption cycles and magmatic processes at a reawakening volcano, Mt. Taranaki, New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Earth Science at Massey University, Palmerston North, New Zealand

Turner, Michael Bruce January 2008 (has links)
Realistic probabilistic hazard forecasts for re-awakening volcanoes rely on making an accurate estimation of their past eruption frequency and magnitude for a period long enough to view systematic changes or evolution. Adding an in-depth knowledge of the local underlying magmatic or tectonic driving processes allows development of even more robust eruption forecasting models. Holocene tephra records preserved within lacustrine sediments and soils on and surrounding the andesitic stratovolcano of Mt. Taranaki (Egmont Volcano), New Zealand, were used to 1) compile an eruption catalogue that minimises bias to carry out frequency analysis, and 2) identify magmatic processes responsible for variations in activity of this intermittently awakening volcano. A new, highly detailed eruption history for Mt. Taranaki was compiled from sediment sequences containing Holocene tephra layers preserved beneath Lakes Umutekai and Rotokare, NE and SE of the volcano’s summit, respectively, with age control provided by radiocarbon dating. To combine the two partly concurrent tephra records both geochemistry (on titanomagnetite) and statistical measures of event concurrence were applied. Similarly, correlation was made to proximal pyroclastic sequences in all sectors around the 2518 m-high edifice. This record was used to examine geochemical variations (through titanomagnetite and bulk chemistry) at Mt. Taranaki in unprecedented sampling detail. To develop an unbiased sampling of eruption event frequency, a technique was developed to distinguish explosive, pumice-forming eruptions from dome-forming events recorded in medial ash as fine-grade ash layers. Recognising that exsolution lamellae in titanomagnetite result from oxidation processes within lava domes or plugs, their presence within ash deposits was used to distinguish falls elutriated from blockand- ash flows. These deposits are focused in particular catchments and are hence difficult to sample comprehensively. Excluding these events from temporal eruption records, the remaining, widespread pumice layers of sub-plinian eruptions at a single site of Lake Umutekai presented the lowest-bias sampling of the overall event frequency. The annual eruption frequency of Mt. Taranaki was found to be strongly cyclic with a 1500-2000 year periodicity. Titanomagnetite, glass and whole-rock chemistry of eruptives from Mt. Taranaki’s Holocene history all display distinctive compositional cycles that correspond precisely with the event frequency curve for this volcano. Furthermore, the largest known eruptions from the volcano involve the most strongly evolved magmas of their cycle and occur during the eruptive-frequency minimum, preceding the longest repose intervals known. Petrological evidence reveals a two-stage system of magma differentiation and assembly operating at Mt. Taranaki. Each of the identified 1500-2000 year cycles represent isolated magma batches that evolved at depth at the base of the crust before periodically feeding a mid-upper crustal magma storage system.
514

Mörkerkörning: Realtidssimulering och visualisering av fordonsbelysning för mörkerkörning i körsimulator / Nighttime Driving: Real-time Simulation and Visualization of Vehicle Illumination for Nighttime Driving in a Simulator

Häggmark, Erik January 2004 (has links)
<p>To give a realistic impression in a driving simulator for nighttime driving, there are many challenging aspects to consider. One of the most important aspects is the illumination caused by the headlights of the own vehicle. To give a realistic impression there is the need to consider the characteristics of the headlight in use to be able to represent main and dipped beam, but also to represent different models and types of headlights. </p><p>Another important aspect is the dazzling effects caused by the light cast by other vehicles upon the driver. These effects are not only important to give a realistic and visually appealing simulation, but also to simulate blinding effects which may affect the drivers ability to perceive the traffic environment to a large degree. </p><p>This thesis describes methods to simulate these vital aspects of night-drive simulation in real-time using the capabilities of today's graphics cards.</p>
515

Mörkerkörning: Realtidssimulering och visualisering av fordonsbelysning för mörkerkörning i körsimulator / Nighttime Driving: Real-time Simulation and Visualization of Vehicle Illumination for Nighttime Driving in a Simulator

Häggmark, Erik January 2004 (has links)
To give a realistic impression in a driving simulator for nighttime driving, there are many challenging aspects to consider. One of the most important aspects is the illumination caused by the headlights of the own vehicle. To give a realistic impression there is the need to consider the characteristics of the headlight in use to be able to represent main and dipped beam, but also to represent different models and types of headlights. Another important aspect is the dazzling effects caused by the light cast by other vehicles upon the driver. These effects are not only important to give a realistic and visually appealing simulation, but also to simulate blinding effects which may affect the drivers ability to perceive the traffic environment to a large degree. This thesis describes methods to simulate these vital aspects of night-drive simulation in real-time using the capabilities of today's graphics cards.
516

L'habitude en matière de conduite automobile : une analyse de ses composantes et du rôle qu'elle joue dans le maintien et la régulation des comportements de conduite

Beaulieu, Nathalie 07 1900 (has links)
« La grande majorité des accidents demeure liée aux comportements dangereux des usagers de la route ». Cet énoncé, lapidaire, fait aujourd’hui figure d’évidence au sein de la communauté des intervenants en sécurité routière. Il repose pourtant sur des prémisses discutables. Le problème le plus fondamental réside dans le fait que la recherche des dernières décennies s’est presque toute entière vouée à l’analyse des seuls aspects défaillants de la conduite (l’accident, les infractions, les erreurs et les fautes de conduite, les conducteurs à risque ou dysfonctionnels, les attitudes et traits de caractère incitant à la conduite dangereuse, etc.). Ce faisant, on a fini par oublier qu’il nous restait encore beaucoup de choses à apprendre sur le fonctionnement usuel de la conduite automobile. Comment, en effet, peut-on escompter élucider tous les rouages de la dynamique accidentelle sans avoir au préalable cerné, et bien compris, les mécanismes de la conduite « ordinaire » ? Comment peut-on parvenir à approfondir notre compréhension des comportements de conduite si l’on fait totalement abstraction de toutes les activités courantes, « normales », auxquelles se livrent les conducteurs lorsqu’ils sont au volant de leur véhicule ? C’est dans la perspective de mieux comprendre les comportements de conduite, dans leur complexité et dans leur diversité, que la présente thèse a été réalisée. Y a plus spécifiquement été examinée la question des habitudes en raison de leur prédominance dans l’activité de la conduite, mais également en raison de leur résistance, des obstacles bien concrets qu’elles sont susceptibles d’opposer à tous ceux qui tentent de modifier les comportements individuels de conduite. Des entrevues en profondeur, menées auprès de trente conducteurs et conductrices âgé(e)s de 17 à 54 ans, devaient permettre de répondre, entre autres, aux questions suivantes : De quoi sont constituées les différentes habitudes en matière de conduite automobile ? Quelle place occupent-elles dans la conduite des individus ? En quoi constituent-elles un frein au changement, à la modification des pratiques adoptées ? Quelles sont les dimensions qui participent à leur installation ? Les résultats de l’analyse ont permis de jeter les bases d’un modèle des comportements de conduite où les sensations corporelles se voient conférer un rôle des plus centraux, et où l’habitude – bien davantage caractérisée par la notion de confort que par celles d’automatisme ou de répétition – concourt non seulement à la pérennité, mais également à la régulation des conduites adoptées sur la route. / “The vast majority of accidents remain related to the dangerous behaviors of road users”. This straightforward statement is now accepted as a truism by the road safety community, although it is based on questionable premises. The most basic problem is that the research done during last decades was almost completely focused on analyzing solely the failing aspects of driving – accidents, traffic offences, driving errors and mistakes, high-risk and dysfunctional drivers, attitudes and psychological traits that may lead to dangerous driving, etc. In so doing, we came to forget that we still have plenty to learn about the art of ordinary driving. How can we expect to address the entire process of road accidents without first having identified, and clearly understood, the mechanisms of “regular” driving? How can we deepen our understanding of driving behaviors if we are completely ignoring all the usual, “normal” activities people do as they are driving their vehicles? This thesis was realized with the view to better understanding the driving behaviors, taking into account their diversity and richness. The study more specifically looked into the issue of habits, as they are a significant aspect of driving behaviors, but also as they are resilient, in that they pose real barriers to all those who are trying to change individual driving behaviors. In-depth interviews with 30 drivers, male and female, aged between 17 and 54, were meant to answer the following questions, among others: What are the different driving habits made of? To what extent do they direct driving behaviors? How do they hamper the change or modification of adopted practices? What are the factors that lead them to set in? The results of the analysis laid the foundations of a driving behaviors model in which body sensations take a central role, and the habit – which is more related to the idea of comfort than to ideas of automatism or repetition – contributes not only to the sustainability, but also to the regulation of the various behaviors adopted on the roads.
517

Les usagers de cannabis et la prise de risque sur la route

Langlois, Julie 05 1900 (has links)
La consommation de cannabis et la conduite sous l’influence du cannabis sont des préoccupations grandissantes dans la société d’aujourd’hui. Le but de la présente étude est d’examiner plus en profondeur la relation entre la fréquence de consommation de cannabis chez les jeunes adultes et la prise de risque sur la route. Les participants (n=48) sont tous des hommes âgés de 18 à 26 ans. Ils ont complété une batterie de questionnaires ainsi qu’une tâche sur simulateur de conduite. Les résultats indiquent que la fréquence de consommation de cannabis est associée positivement avec la prise de risque auto rapportée et suggèrent une tendance positive avec les comportements risqués observés lors de la simulation de conduite en laboratoire. Lorsque les différents groupes de consommateurs sont comparés, ceux qui font un usage quotidien ou multihebdomadaire de cannabis semblent prendre plus de risques au volant que ceux qui consomment une fois semaine et moins ou encore une fois par mois et moins. De plus, il semble que plus les individus consomment fréquemment de la marijuana, plus ils ont tendance à adopter des attitudes permissives en lien avec la conduite sous l’influence de cannabis. Les implications quant à l’intervention sont discutées. / Cannabis use and driving under the influence of cannabis have become a growing concern in today’s society. The aim of the present study was to further examine the relationship between the use frequency of cannabis among young adults and on-road risk taking. Participants (n=48) were all men aged between 18 and 26 years old who were asked to complete questionnaires and to perform in a simulation task. Results indicate that the use frequency of cannabis is positively associated with self-report of risky driving and suggest a trend with observed risk taking behaviour during the simulation. When comparing the different cannabis users, participants who consumed daily or multiple times a week seem to take more risk on the road than those who use cannabis once a week or less and less than monthly. Moreover, it seems that marijuana users who consume more frequently have a tendency of adopting more permissive attitudes toward smoking cannabis and taking the wheel. Implications for interventions are discussed.
518

Methods for machine vision based driver monitoring applications /

Kutila, Matti. January 2006 (has links) (PDF)
Diss. Tampereen teknillinen korkeakoulu, 2006. / Myös verkkojulkaisuna.
519

Ergonomia cognitiva do uso de relógio inteligente durante condução simulada de automóvel: movimento dos olhos e desempenho de motoristas experientes e novatos / Cognitive ergonomics of the use of smartwatch during simulated car driving: eye movement and performance of experienced and novice drivers

Silva, Gustavo de Andrade 30 August 2018 (has links)
Submitted by GUSTAVO DE ANDRADE SILVA (obscuremetaller@gmail.com) on 2018-10-09T01:43:22Z No. of bitstreams: 1 Dissertacao Mestrado - Gustavo de Andrade SIlva.pdf: 6925468 bytes, checksum: 967cb2ee2e821188542fb5b1fb5af49f (MD5) / Rejected by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: 1 - Inserir no corpo do texto a ficha catalográfica, pois é um ítem obrigatório. 2 - Inserir no corpo do texto a cópia da ata de defesa, pois é um ítem obrigatório. Agradecemos a compreensão. on 2018-10-09T12:05:19Z (GMT) / Submitted by GUSTAVO DE ANDRADE SILVA (obscuremetaller@gmail.com) on 2018-10-09T15:27:51Z No. of bitstreams: 1 Dissertacao Mestrado - Gustavo de Andrade SIlva.pdf: 7092505 bytes, checksum: 841cdeae95494c0f93e55115aa751924 (MD5) / Approved for entry into archive by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br) on 2018-10-09T16:59:44Z (GMT) No. of bitstreams: 1 silva_ga_me_bauru.pdf: 7092505 bytes, checksum: 841cdeae95494c0f93e55115aa751924 (MD5) / Made available in DSpace on 2018-10-09T16:59:44Z (GMT). No. of bitstreams: 1 silva_ga_me_bauru.pdf: 7092505 bytes, checksum: 841cdeae95494c0f93e55115aa751924 (MD5) Previous issue date: 2018-08-30 / O relógio inteligente é um novo tipo de eletrônico para o punho com funcionalidades idênticas as de um celular, que também é utilizado por motoristas durante a tarefa de condução do veículo, representando uma nova forma de distração do motorista, e risco aumentado de acidentes no trânsito; uma demanda da ergonomia cognitiva. O objetivo do presente estudo foi determinar o efeito do uso de relógio inteligente sobre motoristas experientes e novatos durante a condução simulada de automóvel, na tarefa de seguir o automóvel à frente, através da análise de movimento dos olhos, da cabeça e do desempenho na condução. Vinte motoristas experientes (EXP) e vinte motoristas novatos (NOV) realizaram a tarefa de seguir um carro à frente por um percurso de 2 km em quatro condições: somente seguir o carro (CAR), seguir o carro e receber uma notificação de texto no relógio inteligente (NOT), seguir o carro que freará de modo inesperado e brusco (FRE) e seguir o carro que freará de modo inesperado e brusco e, adicionalmente, receber uma notificação de texto (FNOT). Os dados do olhar, da cabeça e do desempenho na condução do automóvel foram submetidos à análise de variância de grupo (EXP, NOV) por condição de freada (CAR, FRE) por condição de notificação (NOT, FNOT) por tentativa (1, 2, 3). O desempenho da condução de veículo foi afetado pela freada do carro à frente e pelo uso do relógio inteligente ao receber notificação. Ao receber uma notificação no relógio, mudava-se o foco atencional do trânsito para realizar a leitura de texto, aumentando as chances de ocorrência de acidente. Experientes e novatos apresentaram diferentes estratégias para viabilizar a leitura do texto no relógio; experientes mostraram-se mais eficientes, mas ambos grupos desviaram o olhar da pista em detrimento da atenção, o que resultou em condição de risco. / Smartwatch is a new kind of electronic to be worn on the wrist with features similar to those of mobile phones, they are also being used by drivers during their driving task, representing a new form of distraction for drivers and increasing chances of traffic accidents. The goal of this project is to determine the use effect of smartwatches on experienced and novice drivers while driving on a simulated driving task following a vehicle ahead, through the analysis of eye and head movement and driving performance in a driving simulator. Twenty experienced drivers (EXP) and twenty novice drivers (NOV) will follow a car ahead for 2 kilometers in four conditions: follow a car ahead (CAR), follow a car ahead and receive a text message notification on the smartwatch (NOT), follow a car ahead that brakes abruptly (FRE) and follow a car ahead and receive a text message notification on the smartwatch while the car ahead brakes abruptly (FNOT). The gaze, head movement and driving performance data will be subjected to group variance analysis (EXP, NOV), with or without braking (CAR, FRE), with or without smartwatch notification (NOT, FNOT) and by trial (1, 2, 3). The diver’s performance showed to be affected by the car’s ahead braking and by the use of smartwatch during reading tasks. Attentional focus was shifted away from the road to the smartwatch when drivers tried to perform the reading task, thus increasing the chances of an accident. Experienced and novice drivers used different strategies to perform the reading task while driving; experienced drivers were more efficient but both groups shifted their gaze away from the road in detriment of their attention to the traffic, which resulted in risk conditions.
520

On-board Driver’s Assistance and Assessment System

Damps, Paweł, Czapla, Jacek January 2018 (has links)
The goal of this work is a design and implementation of an on-board driver’s assistance and assessment system. The system overcomes the problem that typical evaluation of skills is performed by experts who may be subjective and are able to consider only a limited number of factors and indicators. The proposed solution is based on eight indicators, which are associated with the vehicle’s speed, acceleration, jerk, engine rotational speed and driving time. These indicators are used to estimate three driving style criteria: safety, economy and comfort. The comprehensive evaluation is done by merging all indicators into one final score. The system is designed according to User-Centred Design method and follows Internet of Things concept. Raspberry Pi minicomputer is used as a central unit to acquire and store the data during the ride and sending them to a server using GSM network. OBD-II interface is used to obtain the data from the vehicle’s network and GPS and accelerometer modules to acquire additional information. MATLAB environment on a local PC is used to process collected data. An outline of the measurements available from ODB-II interface depending on a car model is made. The proposed system has been implemented and evaluated. The evaluation, conducted by collecting readings for specific road actions at different speeds and with different dynamics, confirms that the chosen indicators reliably represent driver’s behaviour. The system was experimentally validated on a group of drivers. The obtained results prove the system’s ability to quantitatively distinguish different driving styles. The system's stability and usability were verified on long-route test. Moreover, the used spider diagram approach established a convenient visualization platform for multidimensional comparison of the result and comprehensive assessment in an intelligible manner. Overall conclusion is that the developed system is a reliable method of the drivers’ behaviour evaluation.

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