Dissertations / Theses: 'Driver performance'

1

Petersen, Andrew. "Driver Training and Driving Performance." Thesis, Griffith University, 2008. http://hdl.handle.net/10072/367642.

Full text

Abstract:

Inertial forces experienced during driving can perturb a driver’s posture, which may in turn diminish a driver’s perceptual sensitivity and corresponding control actions. The general purpose of this study was to investigate the effects of a specific driver-training program taught by Holden Performance Driving Centre (Norwell, Queensland) on driver skill and driving performance as revealed by vehicle motion and postural stability during a range of common driving manoeuvres; emergency braking, cornering, and evasive lane change and return. Three driving experiments were conducted on a closed-circuit track, from which vehicle and driver kinematic data was collected using a variety of instruments. After an initial test-sessions, trainee drivers participated in a driver-training program based upon the development of perceptual-motor skills through enhanced driver’s postural stability as well as instruction in vehicle control strategies that were not primarily reliant upon safety technology, such as an antilock brake system (ABS). A second test-session followed training. For all three experiments, statistical analyses were conducted between cohorts of trainee and control drivers’ first and second test-sessions. For the turning manoeuvres, data from a cohort of driver-training instructors was analysed against the post-test sessions from trainee and control drivers.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Physiotherapy and Exercise Science
Griffith Health
Full Text

APA, Harvard, Vancouver, ISO, and other styles

2

Malik, Husnain. "An assessment system for evaluation of driving competencies." Thesis, Queensland University of Technology, 2011. https://eprints.qut.edu.au/40902/1/Husnain_Malik_Thesis.pdf.

Full text

Abstract:

Automobiles have deeply impacted the way in which we travel but they have also contributed to many deaths and injury due to crashes. A number of reasons for these crashes have been pointed out by researchers. Inexperience has been identified as a contributing factor to road crashes. Driver’s driving abilities also play a vital role in judging the road environment and reacting in-time to avoid any possible collision. Therefore driver’s perceptual and motor skills remain the key factors impacting on road safety. Our failure to understand what is really important for learners, in terms of competent driving, is one of the many challenges for building better training programs. Driver training is one of the interventions aimed at decreasing the number of crashes that involve young drivers. Currently, there is a need to develop comprehensive driver evaluation system that benefits from the advances in Driver Assistance Systems. A multidisciplinary approach is necessary to explain how driving abilities evolves with on-road driving experience. To our knowledge, driver assistance systems have never been comprehensively used in a driver training context to assess the safety aspect of driving. The aim and novelty of this thesis is to develop and evaluate an Intelligent Driver Training System (IDTS) as an automated assessment tool that will help drivers and their trainers to comprehensively view complex driving manoeuvres and potentially provide effective feedback by post processing the data recorded during driving. This system is designed to help driver trainers to accurately evaluate driver performance and has the potential to provide valuable feedback to the drivers. Since driving is dependent on fuzzy inputs from the driver (i.e. approximate distance calculation from the other vehicles, approximate assumption of the other vehicle speed), it is necessary that the evaluation system is based on criteria and rules that handles uncertain and fuzzy characteristics of the driving tasks. Therefore, the proposed IDTS utilizes fuzzy set theory for the assessment of driver performance. The proposed research program focuses on integrating the multi-sensory information acquired from the vehicle, driver and environment to assess driving competencies. After information acquisition, the current research focuses on automated segmentation of the selected manoeuvres from the driving scenario. This leads to the creation of a model that determines a “competency” criterion through the driving performance protocol used by driver trainers (i.e. expert knowledge) to assess drivers. This is achieved by comprehensively evaluating and assessing the data stream acquired from multiple in-vehicle sensors using fuzzy rules and classifying the driving manoeuvres (i.e. overtake, lane change, T-crossing and turn) between low and high competency. The fuzzy rules use parameters such as following distance, gaze depth and scan area, distance with respect to lanes and excessive acceleration or braking during the manoeuvres to assess competency. These rules that identify driving competency were initially designed with the help of expert’s knowledge (i.e. driver trainers). In-order to fine tune these rules and the parameters that define these rules, a driving experiment was conducted to identify the empirical differences between novice and experienced drivers. The results from the driving experiment indicated that significant differences existed between novice and experienced driver, in terms of their gaze pattern and duration, speed, stop time at the T-crossing, lane keeping and the time spent in lanes while performing the selected manoeuvres. These differences were used to refine the fuzzy membership functions and rules that govern the assessments of the driving tasks. Next, this research focused on providing an integrated visual assessment interface to both driver trainers and their trainees. By providing a rich set of interactive graphical interfaces, displaying information about the driving tasks, Intelligent Driver Training System (IDTS) visualisation module has the potential to give empirical feedback to its users. Lastly, the validation of the IDTS system’s assessment was conducted by comparing IDTS objective assessments, for the driving experiment, with the subjective assessments of the driver trainers for particular manoeuvres. Results show that not only IDTS was able to match the subjective assessments made by driver trainers during the driving experiment but also identified some additional driving manoeuvres performed in low competency that were not identified by the driver trainers due to increased mental workload of trainers when assessing multiple variables that constitute driving. The validation of IDTS emphasized the need for an automated assessment tool that can segment the manoeuvres from the driving scenario, further investigate the variables within that manoeuvre to determine the manoeuvre’s competency and provide integrated visualisation regarding the manoeuvre to its users (i.e. trainers and trainees). Through analysis and validation it was shown that IDTS is a useful assistance tool for driver trainers to empirically assess and potentially provide feedback regarding the manoeuvres undertaken by the drivers.

APA, Harvard, Vancouver, ISO, and other styles

3

Shirole, Sushrut Madhukar. "Performance Optimizations for Isolated Driver Domains." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/49107.

Full text

Abstract:

In most of today's operating system architectures, device drivers are tightly coupled with other kernel components. In such systems, a fault caused by a malicious or faulty device driver often leads to complete system failure, thereby reducing the overall reliability of the system. Even though a majority of the operating systems provide protection mechanisms at the user level, they do not provide the same level of protection for kernel components. Using virtualization, device drivers can be executed in separate, isolated virtual machines, called driver domains. Such domains provide the same level of isolation to device drivers as operating systems provide to user level applications. Domain-based isolation has the advantage that it is compatible with existing drivers and transparent to the kernel. However, domain-based isolation incurs significant performance overhead due to the necessary interdomain communication. This thesis investigates techniques for reducing this overhead. The key idea is to replace the interrupt-based notification between domains with a spinning-based approach, thus trading CPU capacity for increased throughput. We implemented a prototype, called the Isolated Device Driver system (IDDR), which includes front-end and back-end drivers and a communication module. We evaluated the impact of our optimizations for a variety of block devices. Our results show that our solution matches or outperforms Xen's isolated driver domain in most scenarios we considered.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

4

Desai, Anup Vijayendra. "Obstructive sleep apnoea and driver performance: prevalence, correlates and implications for driver fatigue." University of Sydney. Medicine, 2003. http://hdl.handle.net/2123/589.

Full text

Abstract:

Obstructive sleep apnoea (OSA) is characterised by repetitive reductions or pauses in breathing during sleep due to upper airway narrowing or closure. Due to disruption to normal sleep patterns, many patients with OSA suffer from increased daytime sleepiness. Epidemiological studies have established a link between OSA and driver fatigue and accidents, generally showing a two to seven times increased risk of road traffic accidents in non-commercial drivers with OSA. There is emerging evidence that commercial drivers have a higher prevalence of OSA than the general population, being predominately male, middle-aged and overweight, three important risk factors for OSA. However, little is known about the relationship between OSA and driver sleepiness in commercial drivers, whether road accidents are increased in commercial drivers with OSA, and whether OSA interacts with other fatigue promoting factors, such as sleep deprivation, to further escalate road accident risk. One thousand randomly selected commercial drivers were surveyed in the field. In addition, 61 randomly selected NSW commercial drivers had in hospital sleep studies and daytime performance testing, including a PC based driving simulator task. The prevalence of OSA, defined as Respiratory Disturbance Index (RDI) < 10, was approximately 50% in NSW commercial drivers. Approximately one quarter of the drivers reported pathological daytime sleepiness, and 12-14% had both OSA and pathological daytime sleepiness. A diagnosis of OSA was the most important factor predicting excessive daytime sleepiness in these drivers: OSA was more important than 15 other work-related, lifestyle and medical factors that could be expected to promote, or be associated with, daytime sleepiness. Drivers with sleep apnoea syndrome (both OSA and pathological daytime sleepiness) had an increased driving accident risk, using driving simulator and daytime performance testing as proxy measures for accident risk. These results demonstrate the importance of OSA as a cause of driver fatigue in commercial drivers and suggest that all commercial drivers should be screened for the presence of sleep apnoea syndrome in order to potentially reduce road accident risk through treatment. A separate, but related body of work examined the combined effects of mild OSA and other fatigue promoting factors (sleep deprivation and circadian influences) on driving performance. Twenty nine subjects, consisting of a group with mild OSA and a group of non-OSA controls, were tested on several occasions throughout the night and day using an intensive performance battery, under both baseline conditions and after a period of 36 hours of total sleep deprivation. The results suggest that drivers with mild OSA are not different to the control group in their response to sleep deprivation or time of day influences. However, the subjects with mild OSA were less aware of their impairment due to sleep deprivation, which is of concern if drivers with OSA are relying on their subjective awareness of fatigue to make decisions about when to stop driving. A final perspective on OSA and driver fatigue is provided through a clinical case series of seven fall-asleep fatality associated MVA�s associated with unrecognised or under-treated sleep disorders. As well as demonstrating the day to day potential for devastating road accidents due, at least in part, to un-recognised or untreated sleep disorders, these cases also serve to highlight some of the current medico-legal controversies and difficulties in this area of driver fatigue. In conclusion, this body of work has provided novel information about the epidemiology and implications of OSA in commercial drivers, and about how OSA interacts with other fatigue promoting factors. Finally, it has explored some of the medico-legal issues that relate to sleep disorders and driver fatigue. As well as providing much needed information in the area of driver fatigue, at the same time this work raises many more questions and suggests areas of future research. For instance, such research should examine the relationship between objective accident rates and OSA/sleep apnoea syndrome in commercial drivers, the interaction between mild sleep apnoea syndrome and other fatigue risk factors, and driver perception of sleepiness prior to sleep onset in drivers with sleep disorders.

APA, Harvard, Vancouver, ISO, and other styles

5

Desai, Anup Vijayendra. "Obstructive sleep apnoea and driver performance: prevalence, correlates and implications for driver fatigue." Thesis, The University of Sydney, 2002. http://hdl.handle.net/2123/589.

Full text

Abstract:

Obstructive sleep apnoea (OSA) is characterised by repetitive reductions or pauses in breathing during sleep due to upper airway narrowing or closure. Due to disruption to normal sleep patterns, many patients with OSA suffer from increased daytime sleepiness. Epidemiological studies have established a link between OSA and driver fatigue and accidents, generally showing a two to seven times increased risk of road traffic accidents in non-commercial drivers with OSA. There is emerging evidence that commercial drivers have a higher prevalence of OSA than the general population, being predominately male, middle-aged and overweight, three important risk factors for OSA. However, little is known about the relationship between OSA and driver sleepiness in commercial drivers, whether road accidents are increased in commercial drivers with OSA, and whether OSA interacts with other fatigue promoting factors, such as sleep deprivation, to further escalate road accident risk. One thousand randomly selected commercial drivers were surveyed in the field. In addition, 61 randomly selected NSW commercial drivers had in hospital sleep studies and daytime performance testing, including a PC based driving simulator task. The prevalence of OSA, defined as Respiratory Disturbance Index (RDI) < 10, was approximately 50% in NSW commercial drivers. Approximately one quarter of the drivers reported pathological daytime sleepiness, and 12-14% had both OSA and pathological daytime sleepiness. A diagnosis of OSA was the most important factor predicting excessive daytime sleepiness in these drivers: OSA was more important than 15 other work-related, lifestyle and medical factors that could be expected to promote, or be associated with, daytime sleepiness. Drivers with sleep apnoea syndrome (both OSA and pathological daytime sleepiness) had an increased driving accident risk, using driving simulator and daytime performance testing as proxy measures for accident risk. These results demonstrate the importance of OSA as a cause of driver fatigue in commercial drivers and suggest that all commercial drivers should be screened for the presence of sleep apnoea syndrome in order to potentially reduce road accident risk through treatment. A separate, but related body of work examined the combined effects of mild OSA and other fatigue promoting factors (sleep deprivation and circadian influences) on driving performance. Twenty nine subjects, consisting of a group with mild OSA and a group of non-OSA controls, were tested on several occasions throughout the night and day using an intensive performance battery, under both baseline conditions and after a period of 36 hours of total sleep deprivation. The results suggest that drivers with mild OSA are not different to the control group in their response to sleep deprivation or time of day influences. However, the subjects with mild OSA were less aware of their impairment due to sleep deprivation, which is of concern if drivers with OSA are relying on their subjective awareness of fatigue to make decisions about when to stop driving. A final perspective on OSA and driver fatigue is provided through a clinical case series of seven fall-asleep fatality associated MVA�s associated with unrecognised or under-treated sleep disorders. As well as demonstrating the day to day potential for devastating road accidents due, at least in part, to un-recognised or untreated sleep disorders, these cases also serve to highlight some of the current medico-legal controversies and difficulties in this area of driver fatigue. In conclusion, this body of work has provided novel information about the epidemiology and implications of OSA in commercial drivers, and about how OSA interacts with other fatigue promoting factors. Finally, it has explored some of the medico-legal issues that relate to sleep disorders and driver fatigue. As well as providing much needed information in the area of driver fatigue, at the same time this work raises many more questions and suggests areas of future research. For instance, such research should examine the relationship between objective accident rates and OSA/sleep apnoea syndrome in commercial drivers, the interaction between mild sleep apnoea syndrome and other fatigue risk factors, and driver perception of sleepiness prior to sleep onset in drivers with sleep disorders.

APA, Harvard, Vancouver, ISO, and other styles

6

Desai, Anup. "Obstructive sleep apnoea and driver performance prevalence, correlates, and implications for driver fatigue /." Connect to full text, 2002. http://hdl.handle.net/2123/589.

Full text

Abstract:

Thesis (Ph. D.)--University of Sydney, 2003.
Includes tables and questionnaires. Title from title screen (viewed Apr. 29, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Medicine. Degree awarded 2003; thesis submitted 2002. Includes bibliography. Also available in print form.

APA, Harvard, Vancouver, ISO, and other styles

7

Krishnapillai, Alagesan. "Understanding key performance indicators through driver measures." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28321.

Full text

Abstract:

Performance management is a vital part of every organization for its success and long term survival in the current competitive global market place. An organization needs a sound performance management framework to analyze its data to make strategic and tactical decisions. The weaknesses in today's performance management frameworks are linked to their inability to integrate strategy formulation with implementation. In our thesis, we introduce D river Measure Models that can define cause-and-effect relationship between d river measures and Key Performance Indicators (KPIs) for effective performance management and strategic alignment. Driver Measure Models make the performance management more dynamic as the operational activities are linked to strategies. Another contribution of the thesis is the identification of mathematical techniques to quantify relationships between KPIs and driver measures. Thesis makes an effort to show how mathematical techniques can be used for planning and forecasting outcomes while changing strategies. After conducting analysis using the mathematical techniques, organization can arrive at a set of operational tasks associated to driver measures which need to be executed to achieve its optimal result. Finally, we identified the essential set of criteria that a performance management framework needs to address through a literature survey and a gap analysis of existing frameworks. We created an extension to the Balanced Scorecard framework based on Driver Measure Models and support for the management of external factors to address these criteria and compared it to existing frameworks using a case study.

APA, Harvard, Vancouver, ISO, and other styles

8

Lai, Frank Chien Hsun. "Driver attentional demand to dual-task performance." Thesis, University of Leeds, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.422623.

Full text

APA, Harvard, Vancouver, ISO, and other styles

9

Desmond, Paula A. "Fatigue and stress in driving performance." Thesis, University of Dundee, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.364944.

Full text

Abstract:

This thesis attempted to provide a detailed theoretical understanding of the effects of task-induced fatigue on simulated driving performance. Previous research has shown that duration of driving has only a weak effect on driving performance. A series of studies were conducted to examine how fatigue effects interact with task demands, and to explore the psychological changes associated with fatigue. The research also explored links between fatigue and stress in terms of their affective reactions and the coping mechanisms which are central to them. The first phase of the research consisted of a series of simulated studies of fatigue. The first study developed an experimental paradigm to examine both task-specific and aftereffects of fatigue on driving performance. The findings showed that fatigue effects interacted with task demands such that drivers' lateral control of the vehicle and trajectory were impaired during low demand rather than in high demand driving episodes. The study also showed that the fatigue state is a multidimensional state which is principally characterised by a reduction in motivation. The second and third studies attempted to explore the role of motivational mechanisms in fatigue-related impairments. This phase of the research showed that impairments in low demand driving conditions may be reduced by enhancing the driver's motivational state. The fourth study explored the development of subjective fatigue in two types of task-induced fatigue. The study showed that there is a dissociation between subjective and objective fatigue. The second phase of the research examined the links between stress and fatigue in simulated and real-life driving environments. The studies showed that stress and fatigue are similar states but there are particular features which make them distinct states. The results from simulated and real-life driving environments showed a high degree of consistency.

APA, Harvard, Vancouver, ISO, and other styles

10

Frid, Alexandra, and Fredrik Åström. "Impaired Driver Performance Detection Identifying driver-independent signs of inattention via in-vehicle sensors." Thesis, KTH, Maskinkonstruktion (Inst.), 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-49625.

Full text

Abstract:

Detta examensarbete är utfört på Scania CV i Södertälje. Det är den avslutande delen av civilingenjörsprogrammet Design och produktframtagning vid Institutionen för maskinkonstruktion på KTH i Stockholm. Mer än 80 procent av alla trafikolyckor som involverar tunga fordon är relaterade till ouppmärksamt förarbeteende. Ouppmärksamhet kan orsakas av antingen trötthet eller distraktioner. Målet med detta examensarbete är att försöka hitta ett sätt att prediktera och detektera den här typen av beteende med hjälp av fordonssignaler. Grunden för analysen är data från SeMiFOT-projektet, ett naturalistiskt fältprov, utfört av gemensamma krafter inom svensk fordonsindustri, forskningsinstitut och University of Michigan. Datat inkluderar videofilm, blickriktnings- och ögonrörelsemönster, samt CAN signaler. De CAN-signaler som använts för analysen inkluderar till exempel styrvinkel och lateral acceleration. För att möjliggöra uppskattning av förarnas trötthetsnivå har en modell som kallas Sleep/Wake Predictor (SWP) använts. Resultatet av arbetet är en modell som består av en riskbedömning kopplad till trötthetsnivån och en algoritm för distraktionsdetektion. Trötthetsdelen använder SWP:n och den välkända KSS skalan för att approximera förarens nuvarande och förväntade trötthetsnivå och riskerna det medför. Distraktionsalgoritmen använder styrvinkelhastigheten som insignal och genererar en distraktionsflagga. De typer av distraktionsmoment som kan detekteras är exempelvis telefonanvändning och justering av utrustning i hytten. Utvariablerna från modellen skickas på fordonets CAN-nätverk. Hur den här informationen bäst skulle kunna presenteras till föraren har inte undersökts i det här projektet. Slutsatsen från projektet är att det faktum att distraktionsbeteende, som är en bidragande orsak till nedsatt förarförmåga, kan detekteras är positivt. Detta i kombination med uppskattningen av trötthet utgör en bra grund för att reducera riskerna för olyckor orsakade av ouppmärksamhet. Detta kan utvecklas till en värdefull produkt som Scania kan erbjuda sina kunder.
This thesis work is conducted at Scania CV in Södertälje. It is the final part of the M.Sc program Design & Product Development at the Institution for Machine Design at KTH, Stockholm. More than 80 percent of all traffic accidents involving heavy trucks are caused by inattentive driver behaviour. Inattention can be caused by either drowsiness or distractions. The aim with this thesis work is to try to find a way to predict and detect such behaviour using vehicle sensors. The basis for the analysis is data from the SeMiFOT project, a naturalistic field operating test, conducted by joint forces between Swedish vehicle manufacturers, research institutes and the University of Michigan. The data includes video footage, gaze direction and eye closure measures, as well as CAN signals. The CAN signals used for analysis are for example steering wheel angle and lateral acceleration. To be able to assess the drivers’ level of sleepiness, a model called the Sleep/Wake Predictor (SWP) has been used. The result of this thesis is a model consisting of a risk level due to sleepiness assessment and a distraction detection algorithm. The sleepiness part uses the SWP and the well known Karolinska Sleepiness Scale (KSS) to approximate the drivers’ current and expected sleepiness level and the risks associated with this. The distraction detection uses the steering wheel angle velocity as input, processes the signal and outputs a distraction warning flag. The type of distractions thatare detectable are for example using a mobile phone and adjusting equipment in the cab. The model output is sent out on the Controller Area Network (CAN) of the vehicle. How the information from the model can be best presented to the driver has not been examined. The conclusion from the project is that the fact that distractive behaviour, which is a contributor to impaired driver performance, can be detected is positive. This, in combination with the assessment of sleepiness, constitutes a good base for reducing the risks of accidents caused by inattention. This can be developed into a valuable product for Scania to offer their customers.

APA, Harvard, Vancouver, ISO, and other styles

11

Chucray, Ashley N. "Comparison Between Familiar and Unfamiliar Driver Performance in a Multi-Lane Roundabout: A Case Study in Athens, Ohio." Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1375115354.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Carpatorea, Iulian. "Methods to quantify and qualify truck driver performance." Licentiate thesis, Högskolan i Halmstad, CAISR Centrum för tillämpade intelligenta system (IS-lab), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-33229.

Full text

Abstract:

Fuel consumption is a major economical component of vehicles, particularly for heavy-duty vehicles. It is dependent on many factors, such as driver and environment, and control over some factors is present, e.g. route, and we can try to optimize others, e.g. driver. The driver is responsible for around 30% of the operational cost for the fleet operator and is therefore important to have efficient drivers as they also inuence fuel consumption which is another major cost, amounting to around 40% of vehicle operation. The difference between good and bad drivers can be substantial, depending on the environment, experience and other factors. In this thesis, two methods are proposed that aim at quantifying and qualifying driver performance of heavy duty vehicles with respect to fuel consumption. The first method, Fuel under Predefined Conditions (FPC), makes use of domain knowledge in order to incorporate effect of factors which are not measured. Due to the complexity of the vehicles, many factors cannot be quantified precisely or even measured, e.g. wind speed and direction, tire pressure. For FPC to be feasible, several assumptions need to be made regarding unmeasured variables. The effect of said unmeasured variables has to be quantified, which is done by defining specific conditions that enable their estimation. Having calculated the effect of unmeasured variables, the contribution of measured variables can be estimated. All the steps are required to be able to calculate the influence of the driver. The second method, Accelerator Pedal Position - Engine Speed (APPES) seeks to qualify driver performance irrespective of the external factors by analyzing driver intention. APPES is a 2D histogram build from the two mentioned signals. Driver performance is expressed, in this case, using features calculated from APPES. The focus of first method is to quantify fuel consumption, giving us the possibility to estimate driver performance. The second method is more skewed towards qualitative analysis allowing a better understanding of driver decisions and how they affect fuel consumption. Both methods have the ability to give transferable knowledge that can be used to improve driver's performance or automatic driving systems. Throughout the thesis and attached articles we show that both methods are able to operate within the specified conditions and achieve the set goal.

APA, Harvard, Vancouver, ISO, and other styles

13

Cassel, Shirley T. (Shirley Tamsen). "Validation of a Test Battery for the Selection of Driver Managers in a Trucking Organization." Thesis, University of North Texas, 1990. https://digital.library.unt.edu/ark:/67531/metadc500800/.

Full text

Abstract:

This study was a concurrent validation of a paper and pencil test battery used at a national trucking company. Forty-eight driver managers were rated by their immediate supervisors with the performance appraisal covering 12 dimensions of job behavior that was developed by the experimenter. The driver managers were also administered the Wesman Personnel Classification Test, the Watson-Glaser Critical Thinking Appraisal, and the California Psychological Inventory (CPI). A biographical information blank was also developed and validated. Most validity correlations were nonsignificant, with the exception of the Dominance scale r = .25 (p < .05), the Self-control scale r = -.25 (p < .05), the Communanlity scale r = .29 (p < .05), and the Flexibility scale r = -.39 (p < .05), with overall performance.

APA, Harvard, Vancouver, ISO, and other styles

14

Auckland, Robin Allen. "The impact of advanced driver assistance systems on vehicle dynamic performance and on the driver." Thesis, University of Leeds, 2008. http://etheses.whiterose.ac.uk/169/.

Full text

Abstract:

This research concerns issues arising in the design and implementation of advanced driver assistance systems, specifically longitudinal and lateral controllers; their effects on the dynamic performance of the vehicle, and their impact on the driver. The current state of the art is discussed as part of an extensive literature review, which highlights prominent gaps in the published research. There is a lack of understanding as to the effects of adverse environmental factors on the vehicle dynamics, and the effects of the systems' on the comfort of the driver. A novel twin track approach was taken to investigate these issues: the effects of the systems' on the vehicle dynamics were monitored using a range of off-line simulation tools, while the systems' impact on the driver was considered using an on-line driving simulator experiment. An adaptive cruise control system was developed, tuned to provide a comfortable response and implemented on a sophisticated off-line 9 degree of freedom vehicle model, with a non-linear tyre model. The system was tested in a range of environmental conditions. These simulations highlighted the good performance of the system in wet conditions, and revealed some possible driver conflicts. Two lateral control systems were developed, one based on a look down methodology, and the second on a more driver emulating look ahead approach. The systems were tested using the same high fidelity vehicle model, and an extensive range of suitable motorway manoeuvres. The systems were compared, proving the comfort and stability benefits of the look ahead system. The longitudinal and lateral control systems were integrated with the University of Leeds driving simulator. Ten subject drivers drove with and without the systems through a range of scenarios, some of which required evasive action. The impact of the systems on the driver, and the driver's response to safety critical scenarios was assessed. Results displayed little safety benefit of the systems in evasive scenarios, but drivers perceived improved awareness and comfort when under their control. The potential of advanced driver assistance systems to make driving a more comfortable and safe experience has been demonstrated, although the system engineer must consider the impact of the systems on the driver throughout their design and implementation.

APA, Harvard, Vancouver, ISO, and other styles

15

Topaloglu, Mehmet Ersan. "Improving Kernel Performance For Network Sniffing." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1097856/index.pdf.

Full text

Abstract:

&
#728
G Sniffing is computer-network equivalent of telephone tapping. A Sniffer is simply any software tool used for sniffing. Needs of modern networks today are much more than a sniffer can meet, because of high network traffic and load. Some efforts are shown to overcome this problem. Although successful approaches exist, problem is not completely solved. Efforts mainly includes producing faster hardware, modifying NICs (Network Interface Card), modifying kernel, or some combinations of them. Most efforts are either costly or no know-how exists. In this thesis, problem is attacked via modifying kernel and NIC with aim of transferring the data captured from the network to the application as fast as possible. Snort [1], running on Linux, is used as a case study for performance comparison with the original system. A significant amount of decrease in packet lost ratios is observed at resultant system.

APA, Harvard, Vancouver, ISO, and other styles

16

Vasquez, Holland Marie. "Effects of a Driver Monitoring System on Driver Trust, Satisfaction, and Performance with an Automated Driving System." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/64506.

Full text

Abstract:

This study was performed with the goal of delineating how drivers' interactions with an Automated Driving System were affected by a Driver Monitoring System (DMS), which provided alerts to the driver when he or she became inattentive to the driving environment. There were two specific research questions. The first was centered on addressing how drivers' trust and satisfaction with an Automated Driving System was affected by a DMS. The second was centered on addressing how drivers' abilities to detect changes in the driving environment that required intervention were affected by the presence of a DMS. Data were collected from fifty-six drivers during a test-track experiment with an Automated Driving System prototype that was equipped with a DMS. DMS attention prompt conditions were treated as the independent variable and trust, satisfaction, and driver performance during the experimenter triggered lane drifts were treated as dependent variables. The findings of this investigation suggested that drivers who receive attention prompts from a DMS have lower levels of trust and satisfaction with the Automated Driving System compared to drivers who do not receive attention prompts from a DMS. While the DMS may result in lower levels of trust and satisfaction, the DMS may help drivers detect changes in the driving environment that require attention. Specifically, drivers who received attention prompts after 7 consecutive seconds of inattention were 5 times more likely to react to a lane drift with no alert compared to drivers who did not receive attention prompts at all.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

17

Davis, Ethan J. "Vehicle dynamics measurement system for evaluating older driver performance." [Gainesville, Fla.] : University of Florida, 2006. http://purl.fcla.edu/fcla/etd/UFE0014284.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Yekhshatyan, Lora. "Detecting distraction and degraded driver performance with visual behavior metrics." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/910.

Full text

Abstract:

Driver distraction contributes to approximately 43% of motor-vehicle crashes and 27% of near-crashes. Rapidly developing in-vehicle technology and electronic devices place additional demands on drivers, which might lead to distraction and diminished capacity to perform driving tasks. This situation threatens safe driving. Technology that can detect and mitigate distraction by alerting drivers could play a central role in maintaining safety. Correctly identifying driver distraction in real time is a critical challenge in developing distraction mitigation systems, and this function has not been well developed. Moreover, the greatest benefit may be from real-time distraction detection in advance of dangerous breakdowns in driver performance. Based on driver performance, two types of distraction - visual and cognitive - are identified. These types of distraction have very different effects on visual behavior and driving performance; therefore, they require different algorithms for detection. Distraction detection algorithms typically rely on either eye measures or driver performance measures because the effect of distraction on the coordination of measures has not been established. Combining both eye glance and vehicle data could enhance the ability of algorithms to detect and differentiate visual and cognitive distraction. The goal of this research is to examine whether poor coordination between visual behavior and vehicle control can identify diminished attention to driving in advance of breakdowns in lane keeping. The primary hypothesis of this dissertation is that detection of changes in eye-steering relationship caused by distraction could provide a prospective indication of vehicle state changes. Three specific aims are pursued to test this hypothesis. The first aim examines the effect of distracting activity on eye and steering movements to assess the degree to which the correlation parameters are indicative of distraction. The second aim applies a control-theoretic system identification approach to the eye movement and steering data to distinguish between distracted and non-distracted conditions. The third aim examines whether changes of eye-steering coordination associated with distraction provide a prospective indication of breakdowns in driver performance, i.e., lane departures. Together, the three aims show how that a combination of visual and steering behavior, i.e., eye-steering model, can differentiate between non-distracted and distracted state. This model revealed sensitivity to distraction associated with off-road glances. The models derived for different drivers have similar structure and fit to data from other drivers reasonably well. In addition, the differences in model order and model coefficients indicate the variability in driving behavior: some people generate more complex behavior than others. As was expected, eye-steering correlation on straight roads is not as strong as observed on curvy roads. However, eye-steering correlation measured through correlation coefficient and time delay between two movements is sensitive to different types of distraction. Time delay mediates changes in lane position and the eye-steering system predicts breakdowns in lane keeping. This dissertation contributes to developing a distraction detection system that integrates visual and steering behavior. More broadly, these results suggest that integrating eye and steering data can be helpful in detecting and mitigating impairments beyond distraction, such as those associated with alcohol, fatigue, and aging.

APA, Harvard, Vancouver, ISO, and other styles

19

Collins, Dennis James. "An Examination of Driver Performance Under Reduced Visibility Conditions When Using An In-Vehicle Signing Information System (ISIS)." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36602.

Full text

Abstract:

Recent technological innovations and the need for increased safety on the world's roads have led to the introduction of In- Vehicle Information Systems (IVIS). These systems will provide navigation and advisory information to drivers while they are driving. One aspect of these systems, In-vehicle Signing Information Systems (ISIS), would provide the warning, regulatory, and advisory information that is currently found on road signs. These systems may be of particular benefit when external elements such as rain, snow, or night driving reduce or eliminate the opportunity for drivers to detect road signs. This study attempts to determine what benefits, if any, are realized by drivers using this system. Fifty-eight drivers operated an instrumented Oldsmobile Aurora under eight conditions. The eight conditions consisted of a daylight-clear weather-ISIS condition, a daylight-clear weather-No ISIS condition, a daylight-rain-ISIS condition, a daylight-rain-No ISIS condition, a night-clear weather-ISIS condition, a night-clear weather-No ISIS condition, a night-rain-ISIS condition, and a night-rain-No ISIS condition. Younger drivers (18-30 years old) and older drivers (65 years or older) took part in this study. Three measures of driver performance were collected along with subjective preference data. Each measure was evaluated in order to determine what impact, if any, weather, time of day, age, and ISIS use had on performance. Subjective data was evaluated to determine driver preference and acceptance of the ISIS display. The results indicated that use of the ISIS display led to reduced speeds and greater reaction distances for all drivers. Evidence was found that seems to indicate that older drivers may receive a greater benefit in complex, unfamiliar, or low visibility situations. Evidence was also found that indicates that all drivers may receive a greater benefit at night for the complex or unfamiliar situations. Subjectively, the majority of the drivers indicated that the ISIS display made them more aware of road sign information.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

20

Almehdi, Österman Sami, and Carl Lundberg. "Development of performance indicators through cost driver identification : an IT department case study." Thesis, KTH, Industriell ekonomi och organisation (Inst.), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-98272.

Full text

Abstract:

The costs of information technology (IT) in large multinational companies (MNCs) often constitute a significant portion of the company’s total yearly turnover. IT departments are on one hand expected to return value to business, but are on the other hand often prone to cost reductions. Thus, it is not unusual that IT management chooses to focus on cost cutting rather than cost control in order to meet the company’s financial targets. Understanding cost drivers in IT is not always evident, making it difficult for managers to know what performance indicators that should be tracked. This study addresses the issue of cost control and performance measurement in IT departments, in the form of a case study carried out at the IT department of a large Swedish MNC in the telecommunications industry. The case company is divided into two parts: Enterprise and Engineering, where Enterprise provides the organization with IT in form of printers, personal computers, applications, IT support and communication services through network infrastructure and voice. Engineering provides research and development units with software development infrastructure and testing environments for products. The testing environments comprise of both software testing through simulations and hardware testing in physical labs. By carrying out interviews with managers and key people responsible for large budget items, 130 cost drivers were identified. After reducing recurring cost drivers and merging similar ones, the cost drivers were filtered according to quantifyability. In a second step, performance indicators were developed using the SMART model and then scored with respect to cost impact and ease of implementation. This resulted in a recommendation of 49 performance indicators to be tracked across the entire IT department. A sample of recommended performance indicators is total cost of wages / number of employees, number of virtualized servers / total number of servers and amount of video related traffic / total capacity of bandwidth. The ambition of this study is to provide a holistic way of controlling cost drivers through prioritized performance indicators. Even though this case is specific to an IT department, the approach in this research may well be applied in other departments and industries.
Kostnaderna för informationsteknologi (IT) i stora multinationella företag utgör ofta en betydande del av företagets totala årliga omsättning. Samtidigt som IT-organisationer förväntas leverera värde till företaget, utsätts de även för kostnadsnedskärningar. Därför är det inte ovanligt att IT-ledningen väljer att fokusera på kostnadsbesparingar, snarare än kostnadskontroll, för att nå bolagets finansiella mål. Det är inte alltid enkelt att förstå vad som driver kostnader i en IT-organisation, vilket försvårar besluten om vilka nyckeltal som IT-ledningen bör styra efter. Denna studie tar upp frågan om kostnadskontroll och prestationsmätning i IT-organisationer i form av en fallstudie, som genomförts på IT-avdelningen på ett stort svenskt multinationellt bolag i telekommunikationsbranschen. Organisationen kan delas in i Enterprise och Engineering, där Enterprise tillhandahåller IT i form av skrivare, persondatorer, applikationer, IT support och kommunikationstjänster genom nätinfrastruktur och taltjänster. Engineering tillhandahåller infrastruktur för mjukvaruutveckling och en miljö för testning av produkter för forsknings- och utvecklingsenheter. Testmiljön består av både mjukvarutestning i form av simuleringar samt tester av hårdvara i fysiska laboratorier. Med utgångspunkt i intervjuer med chefer och andra nyckelpersoner ansvariga för stora budgetposter, identifierades 130 kostnadsdrivare inom IT-avdelningen. Efter reduktion av återkommande kostnadsdrivare och sammanslagning av liknande drivare, filtrerades kostnadsdrivarna med aveseende på kvantifierbarhet. Kostnadsdrivare som var kvantifierbara översattes sedan till nyckeltal med hjälp av SMART-modellen. I efterföljande steg poängsattes nyckeltalen med avseende på kostnadseffekt och möjligheten för implementering. Detta resulterade i en rekommendation av 49 nyckeltal för effektiv kostnadskontroll i hela organisationen. Ett urval av rekommenderade nyckeltal är totala lönekostnaden / antal anställda, antal virtualiserade servrar / totala antalet servrar samt mängden videorelaterad datatrafik / totala bandbreddskapaciteten. Ambitionen med denna studie är att på ett ett holistiskt sätt kontrollera kostnadsdrivare, genom prioritering av nyckeltal. Även om denna fallstudie specifikt riktar sig mot IT-avdelningar, anser författarna att tillvägagångssättet även kan tillämpas på andra avdelningar och branscher.

APA, Harvard, Vancouver, ISO, and other styles

21

Barrett, Pauline R. "Interactions between moderate alcohol consumption and sleepiness : the effect on driver performance." Thesis, Loughborough University, 2005. https://dspace.lboro.ac.uk/2134/15748.

Full text

Abstract:

Both alcohol and sleepiness are known to be major contnbutors to road traffic accidents m the UK. There has been much debate on whether the current legal blood alcohol concentration (BAC) limit for driving (008%) should be lowered to 005%, like several other countries in the European Union. The present limit may be sabsfactory when a driver IS fully alert, however the pressures of today's society mean that an mcreasmg number of people may be sleep deprived. The consequences of a sleepy person drivmg after drinking a current legally acceptable amount of alcohol have not been fully investigated. An initial literature review idenbfied specific areas that needed to be investigated throughout this programme of work The research took the form of a "hfelike" scenario, with only moderate sleep restnction (5h in bed at night) and moderate alcohol consumpbOn, producmg BACs of approximately half the UK legal driving limit The drive, on a Simulated dual carriageway, lasted for 2h and was very monotonous The research programme was split into four main areas (i) young men (the most at risk group of drivers for sleep related crashes) driving in the afternoon (a time when the number of sleep related crashes are known to increase), under a 2 x 2 experimental deSIgn, With and without alcohol at lunch-time and with and without the prior night's sleep restncted to 5h, (u) an identical gender comparison usmg young women, (hi) a time-of-day companson using young men, but with the drive and alcohol consumption takmg place m the early evening (a bme of day when we are naturally more alert); (iv) a near-zero BAC, when young men have the same alcohol intake as in (I) but earlier, such that their BACs have reduced to nearly zero before startIng the afternoon drive. Dunng the afternoon circadian trough the driving performance of both men and women is severely impaired when moderate sleep restriction and alcohol consumption are combined Of particular concern, is that men seem to be unable to perceive this greater impairment Women generally appear to have better perception of alcohol impairment, even without sleep loss. Unlike men, women's driving is less impaired by modest amounts of alcohol when they are alert, which seems to be because they know their performance IS affected and thus apply more compensatory effort. On the other hand, their rrnpamnent after alcohol when combmed WIth sleep loss is well in excess of any compensatory effort. Trrne of day also affects imp3lrment after alcohol and/or sleep loss. Driving performance IS generally better during the early evening holtrS, when we are nat\lfally more alert, compared with the afternoon, and for all conditions. Moderate alcohol intake does not impair drivmg performance during the early evening, unlike during the afternoon. However, if combined with sleepiness, mcreased driving impamnent does become apparent during the early evening, although, not to the extent that it does durmg the afternoon. BACs are not a good indicator of alcohol-related driving impairment, especially when combmed with sleepiness. During the afternoon, even when BACs fall almost to zero at the start of a drive, sleepy drivers are still more impaired for the first hour of the drive if they have consumed this modest amount of alcohol at lunchtime An unexpected rebound improvement m dnvmg performance is seen ID the second hour of the drive In non-sleep deprived, alert drivers, these same near zero BAC levels did not affect driving performance or significantly increase subjective sleepiness. Overall the results indicate that, combined WIth modest sleepiness, the current legal dnnk drive limtt (008%) is too htglt Thts outcome supports recent and extensIve findmgs WIth fatal and senous road crashes in France (Philip et al., 2001). During the afternoon, a time of day when people are nat\lfally less alert BACs of less than half this UK limit will impair driving even in non-sleep depnved people If drivers are also sleepy, this combmation produces dangerous levels of Impairment durmg the afternoon; the combination also leads to impairment (but to a lesser extent) in the early evening The research was carried out with only moderate levels of sleepiness and alcohol consumptIon, It is fair to conclude that driving impairment would be greater if the sleep loss was greater and/or BACs were htgher, but just under the legal liemt Greater public awareness is required on the knowledge that driving after consuming any alcohol when tired or sleepy is extremely dangerous.

APA, Harvard, Vancouver, ISO, and other styles

22

Aria, Erfan. "Investigation of automated vehicle effects on drivers behavior and traffic performance." Thesis, Linköpings universitet, Kommunikations- och transportsystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-126600.

Full text

Abstract:

Advanced Driver Assistance Systems (ADAS) offer the possibility of helping drivers to fulfill their driving tasks. Automated vehicles are capable of communicating with surrounding vehicles (V2V) and infrastructure (V2I) in order to collect and provide essential information about driving environment. Studies have proved that automated vehicles have a potential to decrease traffic congestion on road networks by reducing the time headway, enhancing the traffic capacity and improving the safety margins in car following. Furthermore, vehicle movement and drivers behavior of conventional vehicles will be affected by the presence of automated vehicles in traffic networks. Despite different encouraging factors, automated driving raises some concerns such as possible loss of situation awareness, overreliance on automation and degrading driving skills in absence of practice. Moreover, coping with complex scenarios, such as merging at ramps and overtaking, in terms of interaction between automated vehicles and conventional vehicles need more research. This thesis work aims to investigate the effects of automated vehicles on drivers behavior and traffic performance. A broad literature review in the area of driving simulators and psychological studies was performed to examine the automated vehicle effects on drivers behavior. Findings from the literature survey, which has been served as setup values in the simulation study of the current work, reveal that the conventional vehicles, which are driving close to the platoon of automated vehicles with short time headway, tend to reduce their time headway and spend more time under their critical time headway. Additionally, driving highly automated vehicles is tedious in a long run, reduce situation awareness and can intensify driver drowsiness, exclusively in light traffic. In order to investigate the influences of automated vehicles on traffic performance, a microscopic simulation case study consisting of different penetration rates of automated vehicles (0, 50 and 100 percentages) was conducted in VISSIM software. The scenario network is a three-lane autobahn segment of 2.9 kilometers including an off-ramp, on-ramp and a roundabout with some surrounding urban roads. Outputs of the microscopic simulation in this study reveal that the positive effects of automated vehicles on roads are especially highlighted when the network is crowded (e.g. peak hours). This can definitely count as a constructive point for the future of road networks with higher demands. In details, average density of autobahn segment remarkably decreased by 8.09% during p.m. peak hours in scenario with automated vehicles. Besides, Smoother traffic flow with less queue in the weaving segment was observed. Result of the scenario with 50% share of automated vehicles moreover shows a feasible interaction between conventional vehicles and automated vehicles. Meaningful outputs of this case study, based on the input data from literature review, demonstrate the capability of VISSIM software to simulate the presence of automated vehicles in great extent, not only as an automated vehicle scenario but also a share of them, in traffic network. The validity of the output values nonetheless needs future research work on urban and rural roads with different traffic conditions.

APA, Harvard, Vancouver, ISO, and other styles

23

Boggs, Christopher Matthew. "Field Study to Evaluate Driver Fatigue Performance in Air-Inflated Truck Seats." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/34161.

Full text

Abstract:

This study conducted a series of road tests in the regular fleet operations of a revenue service to better understand the relationship between vehicle seat design and driver fatigue, improve two newly proposed objective methods for evaluating driver fatigue, and provide design guidelines for evaluating and improving vehicle seat characteristics in terms of driver fatigue. Each driver completed a test session on two seat cushions - one a polyurethane foam cushion and one an air-inflated cushion. Objective measurements of pressure distribution were taken throughout each test session, while subjective measurements were collected using surveys taken at one-hour intervals. Based on these results, we find that the air-inflated seat cushion has advantages in terms of subjective measures of comfort, support, and fatigue. We show that the objective measure aPcrms highlights characteristic differences between seat cushions, as the air-inflated seat cushion provides less area in high pressure regions, thus occluding less blood flow to tissue in the seated area. While we were unable to effectively assess the validity of the proposed measures or improve them further, the characteristic difference between seat cushions is not highlighted by using previously existing objective measures. This implies that aPcrms is a more useful measure and should be considered when evaluating the subjective quality of seat cushion designs under dynamic conditions, such as those existing in commercial truck driving.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

24

Alenquer, Daniel Pittella. "Integrating visual stimuli into automotive head-up display to enhance driver performance." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1322595104.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Filtness, Ashleigh J. "Obstructive sleep apnoea and daytime driver sleepiness." Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/8338.

Full text

Abstract:

Driver sleepiness is known to be a major contributor to road traffic incidents (RTIs). An initial literature review identified many studies reporting untreated obstructive sleep apnoea (OSA) sufferers as having impaired driving performance and increased RTI risk. It is consistently reported that treatment with continuous positive air pressure (CPAP) improves driving performance and decreases RTI risk, although most of these studies are conducted less than one year after starting treatment. UK law allows treated OSA patients to continue driving if their doctor states that treatment has been successful. Despite the wealth of publications surrounding OSA and driving, 6 key areas were identified from the literature review as not fully investigated, the: (i) prevalence of undiagnosed OSA in heavy goods vehicle (HGV) drivers in the UK; (ii) impact of sleep restriction on long term CPAP treated OSA compared with healthy controls; (iii) ability of treated OSA participants to identify sleepiness when driving; (iv) impact of one night CPAP withdrawal on driving performance; (v) individual difference in driving performance of long term CPAP treated OSA participants; (vi) choice of countermeasures to driver sleepiness by two groups susceptible to driver sleepiness, OSA and HGV drivers. Key areas (i) and (vi) were assessed using questionnaires. 148 HGV drivers were surveyed to assess OSA symptoms and preference of countermeasures to driver sleepiness. All participants completing the driving simulator study were also surveyed. 9.5% of HGV drivers were found to have symptoms of suspected undiagnosed OSA. Additionally the OSA risk factors were more prevalent for HGV drivers than reported in national statistics reports for the general population. The most effective countermeasures to driver sleepiness (caffeine and a nap) were not the most popular. Being part of a susceptible group (OSA or HGV driver) and prior experience of driver sleepiness did not promote effective choice of countermeasure. Key areas (ii) to (v) were assessed using a driving simulator. Driving simulators present a safe environment to test participants in a scenario where they may experience sleepiness without endangering other road users.

APA, Harvard, Vancouver, ISO, and other styles

26

Neyens, David Michael. "Driver distraction: implications for individuals with traumatic brain injuries." Diss., University of Iowa, 2010. https://ir.uiowa.edu/etd/862.

Full text

Abstract:

Traumatic brain injuries (TBIs) are injuries to the brain associated with the transfer of energy from some external source. There are an estimated 1.4 million TBIs each year, and about half are due to transportation crashes (NINDS, 2007). Driver distraction is defined as a process or condition that draws a driver's attention away from driving activities toward a competing activity (Sheridan, 2004) and has been identified as an under-examined issue for TBI populations (Cyr, et al., 2008). The interaction between the cognitive impairments related to TBIs and the competing demands from driver distraction may be especially problematic. The goal of this dissertation is to investigate the effect of driver distraction on individuals with TBI. This dissertation uses several approaches and data sources: crash data, a TBI registry, a survey of TBI drivers, and an on-road driving study of TBI and non-TBI drivers. Results demonstrate that a subset of TBI drivers are more willing to engage in distracting tasks and they are more likely to have received speeding tickets. TBI drivers involved in crashes were less likely to wear seatbelts and were more likely to be involved in multiple crashes compared to all other drivers in crashes. Additionally, a subset of TBI drivers exhibits more risk-taking while driving that may result from the TBI or a predisposition to take risks. A Bayesian approach was used to analyze the effect of distracting tasks on driving performance of TBI drivers in an on-road study. A simulator study of non-TBI drivers was used to develop prior distributions of parameter estimates. The distracting tasks include a CD selecting task, a coin sorting task, and a radio tuning task. All of the tasks contained visual-manual components and the coin sorting task contained an additional cognitive component associated with counting the currency. This suggests that TBI drivers exhibited worse driving performance during a coin sorting task than the non-TBI drivers in terms of the standard deviation of speed and maximum lateral acceleration of the vehicle. This suggests that the cognitive component of the coin sorting task may be causing the decreased performance for the TBI drivers. Across all tasks, TBI drivers spent a larger percent of the task duration looking at the task with a larger number of glances towards the distraction task than the non-TBI drivers. Driver distractions with cognitive components may be especially problematic for TBI drivers. Future work should investigate if this effect is consistent across more complex cognitive driver distraction tasks (e.g., cell phone usage) for this population. Additionally, future work should validate the high proportion of TBI drivers involved in multiple crashes.

APA, Harvard, Vancouver, ISO, and other styles

27

Reyes, Michelle Lynn. "Examining driver performance in response to work zone interventions in a driving simulator." Thesis, University of Iowa, 2010. https://ir.uiowa.edu/etd/729.

Full text

Abstract:

Reductions in speed and, more critically, speed variability between vehicles are thought to reduce crash risk in work zones. Numerous factors, such as lane width and lateral clearance and activity level, have been shown to influence speed but very little research has considered how multiple factors might interact to affect driver performance in work zones. This study evaluated the effect of work zone barrier type, presence of a lateral buffer, and work zone activity level on measures of speed and lane position. Twelve middle aged and twelve senior subjects drove in a National Advanced Driving Simulator (NADS) MiniSim. The subjects drove faster and with less variability in work zones with concrete barriers. Measures of speed and lane position were more heterogeneous across groups with 42-inch channelizers compared to drums. Speed was reduced and more variable in work areas with a high level of activity than in areas with a low level of activity. On the whole, the presence of a lateral buffer reduced speed variability in the high activity areas but this response was not uniform across all drivers. This research demonstrates that driving simulators can be used to evaluate how work zone factors may interact with one another to affect driver performance for different driver groups. While the results from this study corresponded to observations from actual work zones, the driving simulator must be validated with on-road data before generalizations can be made.

APA, Harvard, Vancouver, ISO, and other styles

28

Bhagavathula, Rajaram. "Effects of Intersection Lighting Design on Driver Visual Performance, Perceived Visibility, and Glare." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/64451.

Full text

Abstract:

Nighttime intersection crashes account for nearly half of all the intersection crashes, making them a major traffic safety concern. Although providing lighting at intersections has proven to be a successful countermeasure against these crashes, existing approaches to designing lighting at intersections are overly simplified. Current standards are based on recommending lighting levels, but do not account for the role of human vision or vehicle headlamps or the numerous pedestrian-vehicle conflict locations at intersections. For effective intersection lighting design, empirical evidence is required regarding the effects of lighting configuration (part of the intersection illuminated) and lighting levels on nighttime visibility. This research effort had three goals. The first was to identify an intersection lighting design that results in the best nighttime visibility. The second goal was to determine the effect of illuminance on visual performance at intersections. The third goal was to understand the relationships between object luminance, contrast, and visibility. To achieve these goals, three specific configurations were used, that illuminated the intersection approach (Approach), intersection box (Box), and both the intersection approach and box (Both). Each lighting configuration was evaluated under five levels of illumination. Visibility was assessed both objectively (visual performance) and subjectively (perceptions of visibility and glare). Illuminating the intersection box led to superior visual performance, higher perceived visibility, and lower perceived glare. For this same configuration, plateaus in visual performance and perceived visibility occurred between 8 and 12 lux illuminance levels. A photometric analysis revealed that the Box lighting configuration rendered targets in sufficient positive and negative contrasts to result in higher nighttime visibility. Negatively contrast targets aided visual performance, while for targets rendered in positive contrast visual performance was dependent on the magnitude of the contrast. The relationship between pedestrian contrast and perceived pedestrian visibility was more complex, as pedestrians were often rendered in multiple contrast polarities. These results indicate that Box illumination is an effective strategy to enhance nighttime visual performance and perceptions of visibility while reducing glare, and which may be an energy efficient solution as it requires fewer luminaires.
Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

29

Gellatly, Andrew William. "The Use of Speech Recognition Technology in Automotive Applications." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30373.

Full text

Abstract:

The research objectives were (1) to perform a detailed review of the literature on speech recognition technology and the attentional demands of driving; (2) to develop decision tools that assist designers of in-vehicle systems; (3) to experimentally examine automatic speech recognition (ASR) design parameters, input modalities, and driver ages; and (4) to provide human factors recommendations for the use of speech recognition technology in automotive applications. Two experiments were conducted to determine the effects of ASR design parameters, input modality, and age on driving performance, system usability, and driver preference/acceptance. Eye movement behavior, steering input behavior, speed maintenance behavior, reaction time to forward scene event, task completion time, and task completion errors when driving and performing in-vehicle tasks were measured. Driver preference/acceptance subjective data were also recorded. The results showed that ASR design parameters significantly affected measures of driving performance, system usability, and driver preference/acceptance. However, from a practical viewpoint, ASR design parameters had a nominal effect on driving performance. Differences measured in driving performance brought on by changes in ASR system design parameters were small enough that alternative ASR system designs could be considered without impacting driving performance. No benefits could be claimed for ASR systems improving driving safety/performance compared to current manual-control systems. Speech recognition system design demonstrated a moderate influence on the usability of in-vehicle tasks. Criteria such as task completion times and task completion errors were shown to be different between speech-input and manual-input control methods, and under different ASR design configurations. Therefore, trade-offs between ASR system designs, and between speech-input and manual-input systems, could be evaluated in terms of usability. Finally, ASR system design had a nominal effect on driver preference/acceptance. Further research is warranted to determine if long-term use of ASR systems with less than optimal design parameters would result in significantly lower values for driver preference/acceptance compared to data collected in this research effort. Human factors recommendations for the use of ASR technology in automotive applications are included. The recommendations are based on the empirical research and the literature review on speech recognition technology and the attentional demands of driving.
Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

30

Adefe, Kalama. "A study of competency as a driver for business performance in Nigerian banks." Thesis, University of Sunderland, 2017. http://sure.sunderland.ac.uk/8550/.

Full text

Abstract:

The Nigerian banking industry plays a critical role in its economy because of a number of jobs generated, contributing to financial stability due to the financial services provided by the banks. As Nigeria becomes tirelessly active in its pursuit of global economic integration and recognition, the entry of international banks in the Nigerian banking industry will increase, therefore, competition will, too. As a result, recognising the importance of competencies and competency frameworks to the bank's performance becomes important in improving the bank’s core competencies and competitiveness. A critical review of the literature reveals that many researchers lay emphasis on the importance of competencies on performance. However, there is a lack of empirical study on competence in Nigerian banks. Therefore, this study investigates the influence of competencies on the performance of Nigerian banks. In order to achieve this aim, the researcher conducted a field survey of ten Nigerian banks and the Central Bank of Nigeria (CBN) with the use of qualitative semi-structured interviews. The researcher conducted thirty-one interviews with the staff of the ten selected banks and the CBN. Consequently, the interview data collected was analysed using Nvivo in order to achieve the aim of the research. The findings revealed that Nigerian banks do use competencies which are influencing the performance of the banks. Findings from this research support the findings of other international research on competencies; therefore, suggesting the theory of competency and performance applies to Nigerian banks. This research contributes to existing literature, which highlights the strategic and operational importance of competencies on performance by focusing on Nigerian banks. In conclusion, this research proposes a wider sample size covering all the banks in Nigeria and using both qualitative and quantitative research methods to provide a more accurate finding on the influence of competency in Nigerian banks.

APA, Harvard, Vancouver, ISO, and other styles

31

Zeman, Ethan A. "Determining the reliability and quality performance of a new universal electrical connector driver /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1328064251&sid=35&Fmt=2&clientId=1509&RQT=309&VName=PQD.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Molina, Cuellar Luis G. "IT resources and IT capabilities as a driver of physical infrastructure projects performance." Doctoral thesis, Pontificia Universidad Católica del Perú, 2017. http://tesis.pucp.edu.pe/repositorio/handle/123456789/12012.

Full text

Abstract:

This study evaluates how Information Technology (IT) creates value in the performance of physical infrastructure (PI) projects. The research model is based on the concept of the Business Value of Information Technology (BVIT) and relates the integration of IT resources with the development of IT capabilities to promote the performance of PI projects. The model is evaluated empirically from first-hand data collected from surveys in public and private organizations whose core is the development of PI projects in Colombia. The empirical test indicates there is a strong relationship between IT and PI performance when the effects of IT resources and capabilities are mediated through the underlying mechanisms composed by IT support for competitive strategies and core competencies. The strong correlation between predictor constructs and PI project performance is confirmed upon calculating the total effects, after which the empirical results shall confirm the theoretical basis. The study includes managerial traits like moderator variables and empirical results indicate there are no heterogeneity issues. When countries achieve a foundational level of physical infrastructure, namely in basic services (i.e. water supply and sanitation), infrastructure for life and coexistence (i.e. housing, education, health, etc.) and ports and transport systems, they promote their national productivity and competitive edge, in turn increasing their social positions in relation to equity and sustainability. These transversal and relevant effects in the social context suggest to develop new studies in this field
Tesis

APA, Harvard, Vancouver, ISO, and other styles

33

FUNKE, GREGORY J. "THE EFFECTS OF AUTOMATION AND WORKLOAD ON DRIVER PERFORMANCE, SUBJECTIVE WORKLOAD, AND MOOD." University of Cincinnati / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1193000603.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

GALAVOTTI, ILARIA. "Scelte di raggio d'azione ed esperienza aziendale: driver e risultati nel contesto delle acquisizioni." Doctoral thesis, Università Cattolica del Sacro Cuore, 2016. http://hdl.handle.net/10280/10805.

Full text

Abstract:

La tesi si focalizza sul ruolo dell’esperienza come fattore chiave sia nelle scelte di acquisizione sia in relazione alla performance post-acquisizione. Partendo da una review della letteratura sul tema pubblicata tra il 1980-2015 e utilizzando un dataset composto da 826 acquisizioni completate negli anni 2007-2013 da acquirenti operanti in diversi settori produttivi e localizzati in 61 paesi, il presente lavoro propone tre articoli empirici. Il primo articolo, ancorato all’impianto teorico dell’apprendimento organizzativo, declina il costrutto di esperienza in esperienza in acquisizioni internazionali, esperienza in acquisizioni domestiche ed esperienza internazionale con l’obiettivo di esaminare l’influenza dei diversi tipi di esperienza sulla crescita geografica realizzata attraverso acquisizioni. Utilizzando la prospettiva resource-based view congiuntamente al concetto di liability of foreignness, il secondo articolo analizza le scelte di estensione del raggio d’azione: mantenendo il focus sulla relazione tra correlazione di business ed estraneità del mercato target, si investigano gli effetti di moderazione delle precedenti esperienze in diversificazione produttiva e internazionalizzazione. Infine, il terzo articolo, basato sul concetto di apprendimento esperienziale, esplora il legame tra esperienza e performance post-acquisizione analizzando l’effetto congiunto di esperienza e performance pre-acquisizione.
This thesis focuses on the role of experience as a driver of acquisition behavior and as a factor affecting post-deal performance. Building on a review of the literature published between 1980-2015 on the role of experience in the context of acquisitions and using a full dataset of 826 acquisitions completed between 2007-2013 by acquirers operating in different industries and located in 61 countries, three empirical papers are proposed. The first paper draws on organizational learning theory and disentangles the construct of experience into cross-border acquisition experience, domestic acquisition experience, and international experience with the aim to examine how different types of experience impact on the geographic scope of acquisitions. Building on resource-based view and liability of foreignness, the second empirical paper analyzes corporate scope growth decisions with a focus on the relationship between acquirer-to-target relatedness and market unfamiliarity and on the moderating effects of prior diversification and international experience. Finally, the third paper investigates the experience-performance link with experiential learning as theoretical underpinning and, specifically, analyzes the joint effect of experience accumulation and prior firm performance on post-acquisition performance.

APA, Harvard, Vancouver, ISO, and other styles

35

Heisinger, Aaron E. "Association between driver-reported sleep and predicted behavior of effectiveness based on the Fatigue Avoidance Scheduling Tool." Thesis, Monterey, Calif. : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/Jun/09Jun%5FHeisinger.pdf.

Full text

Abstract:

Thesis (M.S. in Operations Research)--Naval Postgraduate School, June 2009.
Thesis Advisor(s): Miller, Nita Lewis. "June 2009." Description based on title screen as viewed on July 10, 2009. Author(s) subject terms: Large truck crash, long-haul truck drivers, heavy truck operations, Large Truck Crash Causation Study, effects of fatigue on driver performance, long-haul operations, commercial transportation carriers, Federal Motor Carrier Safety Administration, National Highway Traffic Safety Administration. Includes bibliographical references (p. 35-37). Also available in print.

APA, Harvard, Vancouver, ISO, and other styles

36

Imbeau, Daniel. "Effects of instrument panel luminance and hue on simulator driving performance and driver preferences." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/77801.

Full text

Abstract:

Twenty-four subjects, each having a valid Virginia driver's license (males and females of ages from 20 to 73), read aloud words presented on two displays while driving a simulated vehicle in night-time conditions. The words, emulating printed legends found on automobile instrument panels, were presented in different hues (eight levels), brightnesses (two levels), character sizes (four levels), and word complexities (two levels). The brightness levels had been subjectively determined in a preliminary experiment by subjects representative of the older and younger segments of the driver population. Each of two groups of drivers determined one brightness level that was subjectively equal among the eight hues. For each word presented, six reading and driving performance measures were taken. Also, subjective attractiveness, subjective comfort, and subjective ease of readability of each hue by brightness treatment combination, were measured. Globally, the results tend to indicate that color of illumination per se had a reliable effect on subjective preferences but a negligible effect on reading and driving performance. Brightness had an impact on performance only with the smaller character sizes. For the larger sizes, brightness level as selected by the subjects (in the preliminary experiment) had a negligible effect on performance. Character size had marked effects on both performance and subjective preferences. The two smaller character sizes tested yielded significant performance decrements for older drivers while the two larger sizes yielded best performance and were better accepted by all subjects. Word complexity did show a significant effect on glance time at the displays with all character sizes. The results of the experiment were transformed into a set of guidelines for use in design of automobile instrument panels. A number of recommendations for future research are also included.
Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

37

Aich, Sudipto. "Evaluation of Driver Performance While Making Unprotected Intersection Turns Utilizing Naturalistic Data Integration Methods." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/76892.

Full text

Abstract:

Within the set of all vehicle crashes that occur annually, of intersection-related crashes are over-represented. The research conducted here uses an empirical approach to study driver behavior at intersections, in a naturalistic paradigm. A data-mining algorithm was used to aggregate the data from two different naturalistic databases to obtain instances of unprotected turns at the same intersection. Several dependent variables were analyzed which included visual entropy, mean-duration of glances to locations in the driver's view, gap-acceptance/rejection time. Kinematic dependent variables include peak/average speed, and peak longitudinal and lateral acceleration. Results indicated that visual entropy and peak speed differs amongst drivers of the three age-groups (older, middle-age, teens) in the presence of traffic in the intersecting streams while negotiating a left turn. Although not significant, but approaching significance, were differences in gap acceptance times, with the older driver accepting larger gaps compared to the younger teen drivers. Significant differences were observed for peak speed and average speed during a left turn, with younger drivers exhibiting higher values for both. Overall, this research has resulted in contribution towards two types of engineering application. Firstly, the analyses of traffic levels, gap acceptance, and gap non-acceptance represented exploratory efforts, ones that ventured into new areas of technical content, using newly available naturalistic driving data. Secondly, the findings from this thesis are among the few that can be used to inform the further development, refinement, and testing of technology (and training) solutions intended to assist drivers in making successful turns and avoiding crashes at intersections.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

38

Back, Linn, and Isabelle Landberg. "Culture as a Driver of Innovation Performance : A case study at the ASSA ABLOY Group." Thesis, KTH, Maskinkonstruktion (Inst.), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-157316.

Full text

Abstract:

Innovation has become increasingly important for organizations to sustain their competitive advantage. Among the factors frequently put forward as drivers of innovation are for instance innovation strategies, -processes, -tools, and –methods. Alongside these traditional managerial means, there is also explicit focus on innovation climate and –culture. Organizational culture has been proposed as a key factor in explaining innovation in firms, in particular in the light of high-performing and innovative firms such as Google and Apple. There is growing evidence implying that cultures supporting new-product development processes can foster innovative behaviors (Jassawalla and Sashittal, 2002). This supportive organizational culture can be defined as an innovation culture. Nevertheless, despite its apparent importance there is limited research investigating the relationship between innovation performance and organizational culture (McLean, 2005). This study aims to describe an innovation culture and the potential inter-relations there are between innovation culture and innovation performance. The study based on an extensive literature study within the area of organizational culture from where an analytical framework was developed including the following cultural factors, which are proclaimed to stimulate innovation; challenging work, collaboration, competition, empowerment, encourage change, freedom, innovation support, open communication, organizational encouragement and risk-taking. Moreover, a framework for measuring innovation performance was developed where the innovation performance was divided into four dimensions in the innovation process; Ideation, Ideation Output, Implementation and Output. The study uses both qualitative and quantitative methods for collecting data in terms of 38 interviews and 510 useful survey answers from 13 organizations. Results from the interviews were summarized and analyzed within-case and cross-case, while the survey results were analyzed with a regression analysis for uncovering potential relations between the cultural factors and innovation performance. Main findings from the study are the outcome from the regression analysis confirming five of the ten cultural factors to be significant for innovation performance; competition, encourage change , innovation support, organizational encouragement and risk-taking. Further the study confirms a few specific factors of the innovation culture that have higher impact on the innovation performance in specific dimensions than others. By clarifying inter-relationships between innovation performance in specific dimensions and different aspects of innovation culture, an identification of a deficient innovation performance dimension opens up for changes in the innovation culture, enabling to deploy supportive processes, procedures and roles to reach concrete output. Keywords: organizational culture, innovation culture, innovation performance
Innovation har blivit allt viktigare för att bibehålla företags konkurrenskraft. Bland de faktorer som ofta framförts som drivkraft för innovation återfinns till exempel innovationsstrategier, -processer, -verktyg och -metoder. Vid sidan av dessa traditionella metoder finns det också ett uttalat fokus på innovationsklimat och -kultur. Organisationskultur har fastslagits som en viktig faktor för att förklara innovation i företag, i synnerhet hos högpresterande och innovativa företag som Google och Apple. Det finns allt fler bevis som pekar på att företagskultur som stöder nya produktutvecklingsprocesser kan främja innovativa beteenden (Jassawalla och Sashittal, 2002). Denna stödjande organisationskultur kan definieras som en innovationskultur . Trots sin uppenbara betydelse finns det dock förhållandevis lite forskning som undersöker sambandet mellan innovation och organisationskultur (McLean, 2005). Denna studie syftar till att beskriva en innovationskultur, samt hitta de inbördes relationer finns mellan innovationskultur och innovation. Baserat på en omfattande litteraturstudie inom organisationskultur utvecklades ett analytiskt ramverk. Följande kulturella faktorer som påstås stimulera innovation inkluderades; utmanande arbete, samarbete, tävling, egenmakt, uppmuntran till förändring, frihet, innovationssupport, organisatorisk uppmuntran, öppen kommunikation, och risktagande. Dessutom utvecklades ett ramverk för att mäta innovationsprestanda där den delades upp enligt fyra faser i innovationsprocessen; Ideation, Ideation output, Implementation och Output. Studien är en fallstudie och använder sig av både kvalitativa och kvantitativa metoder för insamling av data i form av 38 intervjuer och 620 enkätsvar från 13 olika företag. Resultaten från intervjuerna sammanfattades och analyserades within-case och cross-case. Resultat från enkäten analyserades med en regressionsanalys för att hitta eventuella relationer mellan de kulturella faktorerna och innovationsprestandan. Betydande resultat från studien är bland annat resultatet från regressionsanalysen som bekräftar fem av de tio kulturella faktorer signifikanta för innovationsarbetet; tävling, uppmuntran till förändring, innovationssupport, organisatorisk uppmuntran och risktagande. Vidare bekräftar studien att vissa faktorer inom innovationskultur har större påverkan på innovationsprestandan i specifika faser än andra. Genom att klargöra sambanden mellan innovationsprestanda i specifika faser och olika aspekter av innovationskulturen, kan en identifiering av en bristfällig innovationsprestanda i en av faserna öppna upp för förändringar i innovationskulturen. Detta möjliggör implementering av stödjande processer, rutiner och roller för att nå konkreta resultat. Nyckelord: företagskultur, innovationskultur, innovationsprestanda

APA, Harvard, Vancouver, ISO, and other styles

39

Lewin, Mark Gustav. "Simulator test and evaluation of a drowsy driver detection system and revisions to drowsiness detection algorithms." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-08222008-063044/.

Full text

APA, Harvard, Vancouver, ISO, and other styles

40

Wu, Gang Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "The impact of inter-company network technology on correlations between supply chain drivers and performance measures." Publisher:University of New South Wales. Mechanical & Manufacturing Engineering, 2009. http://handle.unsw.edu.au/1959.4/43645.

Full text

Abstract:

This research aims to examine how, and to what extent, the advanced network technology such as custom-built large-scale network, or internet-based technology contribute to the correlations between supply chain drivers and performance measures. The uniqueness of the research is to use network technology as a leverage factor, instead of merely one of the supply chain drivers, to analyse how it would impact on the correlations between supply chain drivers and performance measures. Through literature review, we identified the key drivers in supply chain and the key performance indicators as independent and dependent variables respectively for data analysis in the research. We consider the utilisation of network technology as a selection variable in the analysis. We also proposed a set of research questions and hypotheses resulting from the literature review. The subsequent data analyses attempted to find answers for these questions and test the validity of the hypotheses. This was achieved by a field survey for 1035 major Australian firms through a structured questionnaire. The response rate of the survey was 20.8%. All these data were analysed with statistical models such as reliability test, multi-collinearity test, MANOVA procedures, factor analysis, and multiple regression modelling to validate whether the survey was robust and how the leverage factor (network technology) would impact on the correlations between supply chain drivers and performance measures. Each research question and hypothesis was reviewed, validated, and concluded based on the results from data analysis. The key findings from the data analysis support the perception that the network technologies with their external customers and suppliers dramatically affect the correlations between supply chain drivers and performance measures. Statistically it actually determines whether the supply chain will success or fail when comparing firms using the technologies with firms not using them. In general, the impact on the correlations is directional and positive. A set of validated theoretical models was also proposed to depict the dynamics between supply chain variables under the influence of network technology. Implications of the findings are also provided in the thesis.

APA, Harvard, Vancouver, ISO, and other styles

41

Powell, Jared Alan. "The Effect of Directional Auditory Cues on Driver Performance in a Simulated Truck Cab Environment." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/36412.

Full text

Abstract:

A human factors experiment was conducted to investigate the potential benefits of using directional auditory cues in intelligent transportation system technologies in commercial vehicles. Twelve licensed commercial vehicle operators drove a commercial truck-driving simulator and were prompted to select highway numbers on a side-task display. Prompts were presented visually or aurally. Auditory prompts were presented either diotically (both ears simultaneously) or directionally (to either the left or right ear). The search task varied in map density and timing of the prompts in relation to speed limit changes. All experimental conditions were compared to a control condition containing no secondary task. Both driving performance (lane deviation, steering wheel angle, road heading angle error, accidents, and adherence to the speed limit) and secondary task performance (accuracy and response time) measures were collected. Results showed that drivers were able to respond more quickly and accurately to the search task when directional auditory cues were used. Results also showed that driving performance degrades when display density increases and that the use of directional auditory prompts lessens this deterioration of performance for high-density conditions.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

42

Mitra, Neal A. "Driver performance--a study of metrics that measure it and environmental conditions that affect it." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/11778.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Morgan, Justin. "HYSTERESIS EFFECTS IN DRIVING." Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3236.

Full text

Abstract:

This dissertation presents two studies examining the interaction between workload history and driver mental workload. The first experiment focuses on testing for the presence of a hysteresis effect in the driving task. The second experiment examines the proposition that cueing impending periods of higher task demand can reduce the impact of any such potential hysteresis effects. Thirty-two licensed drivers served as participants and all served in both studies. Using the directions provided by a Heads-Up-Display navigation system, participants followed a pre-set route in the simulated environment. At specified points within the drive, the navigation system would purposefully fail which required drivers to relay a ten digit alphanumeric error code to a remote operator in order to reset the system. Results indicated that this increase in task demand from the navigation system's failure leads to a significant increase in perceived mental workload as compared to pre-failure periods. This increase in driver mental workload was not significantly reduced by the time the drive ended, indicating the presence of a hysteresis effect. In the second experiment, the navigation system provided a completely reliable visual warning before failure. Results indicate that cueing had neither an effect on perceived mental workload, nor any ameliorating effect on the hysteretic type effect seen in mental workload recovery. The conclusion of these findings being that the overall safety and efficiency of the surface transportation system would likely improve by designs which accommodate the periods immediately following a reduction in stress. Whether from leaving high demand areas such as work zones or in the period immediately after using a in-car information device such as a GPS or a cell phone, these post-high workload periods are associated with increased variability in driver inputs and levels of mental workload.
Ph.D.
Department of Psychology
Sciences
Psychology PhD

APA, Harvard, Vancouver, ISO, and other styles

44

Zimasa, Tatjana. "The influence of mood and cognitive load on driver performance : using multiple measures to assess safety." Thesis, University of Leeds, 2018. http://etheses.whiterose.ac.uk/22189/.

Full text

Abstract:

Emotions and moods are an inevitable part of human life. Previous research suggests that positive and negative moods affect human performance in many aspects: decision making, perception, reasoning and memory. The influence of mood on drivers’ behaviour has been studied to a less extent and mainly with respect to negative emotions. The studies reported in this thesis are based on psychological theories regarding the differences in the effects of positive and negative moods on information processing and mind wandering. The thesis describes two studies: a desktop study and a driving simulator study, which measure drivers’ responses to the actions of other traffic, their observational patterns and driving behaviours in a variety of scenarios. The effects of neutral, happy, sad and angry moods were studied. The simulator study also investigated possible ways to disconnect drivers’ minds from mood induced mind wandering by using different types of cognitive load. The results suggest that mood valence and arousal have different effects on driving safety, with negative moods resulting in the most dangerous driving. In order to draw conclusions about the effect of mood, a combination of multiple measures (e.g. glance patterns, driving performance and drivers’ physiological measures) should be analysed. The results also suggest that some amount of cognitive load, applied while driving, can have a positive effect on drivers’ attention. Further research is needed to establish the amount and type of the cognitive load necessary to improve drivers’ ability to maintain their attention on the driving task. Studies with a larger number of participants and field studies are needed to validate the findings. It is suggested that the findings are used to improve in-car assistance systems able to both detect the harmful effects of a driver’s emotional state and re-direct their attention to the primary task of driving.

APA, Harvard, Vancouver, ISO, and other styles

45

Teh, Evona Thien Thien. "Development of a workload estimator : the influence of surrounding traffic behaviour on driver workload and performance." Thesis, University of Leeds, 2014. http://etheses.whiterose.ac.uk/6882/.

Full text

Abstract:

The consumers’ increasing desire to be connected at all times and the advancement of integrated functionality within the vehicle, increases the risk that drivers could be faced with information overload while driving. Given the importance of human interaction with technology within the vehicle, automobile manufacturers are introducing workload manager systems within the vehicles to help prevent driver overload. However the ability of the system to decide in a timely manner requires anticipation of changes in workload, depending on the capacity of the driver and matching it with the demand expected from the driving task such as the dynamic traffic environment. In relation to the need to understand the influence of traffic demand on driver workload, the work here comprises the systematic manipulation of traffic complexity and exploration of workload measures to highlight which are sensitive to primary task demand manipulated. A within-subjects design was used in the studies explored in this thesis to allow comparison between different manipulated traffic conditions. In the first simulator test, the ability of various objective and subjective workload measures to tap into drivers’ momentary workload was examined. Following the identification of a subjective measure that was sensitive to the influence of lane changes performed by neighbouring vehicle on drivers’ momentary workload, the characteristics of the lane change were explored in the subsequent studies involving single and dual-task conditions. Overall, these studies suggested suppression of non-urgent communications by a workload manager during safety-critical conditions involving critical cut-ins would be advantageous to both younger and older drivers. This thesis offers a novel and valuable contribution to the design of a workload estimator so as to ensure that the driving demand is always within drivers’ capacity to avoid driver overload. Results of these studies have also highlighted the utility of vehicle-based sensor data in improving workload manager functionality.

APA, Harvard, Vancouver, ISO, and other styles

46

Kang, Yong Suk. "Development of Predictive Vehicle Control System using Driving Environment Data for Autonomous Vehicles and Advanced Driver Assistance Systems." Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/85106.

Full text

Abstract:

In the field of modern automotive engineering, many researchers are focusing on the development of advanced vehicle control systems such as autonomous vehicle systems and Advanced Driver Assistance Systems (ADAS). Furthermore, Driver Assistance Systems (DAS) such as cruise control, Anti-Lock Braking Systems (ABS), and Electronic Stability Control (ESC) have become widely popular in the automotive industry. Therefore, vehicle control research attracts attention from both academia and industry, and has been an active area of vehicle research for over 30 years, resulting in impressive DAS contributions. Although current vehicle control systems have improved vehicle safety and performance, there is room for improvement for dealing with various situations. The objective of the research is to develop a predictive vehicle control system for improving vehicle safety and performance for autonomous vehicles and ADAS. In order to improve the vehicle control system, the proposed system utilizes information about the upcoming local driving environment such as terrain roughness, elevation grade, bank angle, curvature, and friction. The local driving environment is measured in advance with a terrain measurement system to provide terrain data. Furthermore, in order to obtain the information about road conditions that cannot be measured in advance, this work begins by analyzing the response measurements of a preceding vehicle. The response measurements of a preceding vehicle are acquired through Vehicle-to-Vehicle (V2V) or Vehicle-to-Infrastructure (V2I) communication. The identification method analyzes the response measurements of a preceding vehicle to estimate road data. The estimated road data or the pre-measured road data is used as the upcoming driving environment information for the developed vehicle control system. The metric that objectively quantifies vehicle performance, the Performance Margin, is developed to accomplish the control objectives in an efficient manner. The metric is used as a control reference input and continuously estimated to predict current and future vehicle performance. Next, the predictive control algorithm is developed based on the upcoming driving environment and the performance metric. The developed system predicts future vehicle dynamics states using the upcoming driving environment and the Performance Margin. If the algorithm detects the risks of future vehicle dynamics, the control system intervenes between the driver's input commands based on estimated future vehicle states. The developed control system maintains vehicle handling capabilities based on the results of the prediction by regulating the metric into an acceptable range. By these processes, the developed control system ensures that the vehicle maintains stability consistently, and improves vehicle performance for the near future even if there are undesirable and unexpected driving circumstances. To implement and evaluate the integrated systems of this work, the real-time driving simulator, which uses precise real-world driving environment data, has been developed for advanced high computational vehicle control systems. The developed vehicle control system is implemented in the driving simulator, and the results show that the proposed system is a clear improvement on autonomous vehicle systems and ADAS.
Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

47

Rjabovs, Aleksandrs. "Performance shaping factors affecting driver safety-related behaviour in urban rail systems : Tyne & Wear Metro case." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/4039.

Full text

Abstract:

It is accepted that train drivers’ safety performance is affected by numerous performance shaping factors (PSF). Design of the physical environment is among these factors. Even though the body of knowledge in rail human factors is increasing, it is limited as it is often i) reactive, ii) focusing mainly on single type incidents, iii) prioritising high profile accidents, iv) not always fully addressing existing risk profiles. Railway systems with different design features are usually grouped together for research purposes thus disregarding the fact that system design can alter effects of the PSFs. This is especially true for urban rail systems. A combination of concurrent and sequential research in this mixed methods thesis has investigated PSFs associated with metro systems design, using the Tyne & Wear Metro system as its application case. The PSFs embedded in everyday operations have been studied on different system levels through historic incident analysis, drivers’ surveys, semi-structured interviews, eye-tracking and simulation experiments. Some of the established methodologies have been adapted in order to address the research objectives set. Novel approaches have been developed for the deployment of in-service eye-tracking using dynamic areas of interest and the development of a low-cost high fidelity simulator using gaming software and hardware. Selected station layouts have been assessed through measures of workload, stress and signal checking behaviour thus supporting PSF inter-dependence. The results suggest the influence on the performance of arrival and departure procedures of the angle between a signal, a driver and a mirror. Among the latent conditions potentially inducing incident propagation are passenger levels, the platform side, informativeness of design elements, openness and lighting conditions of a station, and distances from a stopping position to other elements of the station design.

APA, Harvard, Vancouver, ISO, and other styles

48

McLaughlin, Shane Brendan. "Analytic Assessment of Collision Avoidance Systems and Driver Dynamic Performance in Rear-End Crashes and Near-Crashes." Diss., Virginia Tech, 2007. http://hdl.handle.net/10919/29561.

Full text

Abstract:

Collision avoidance systems (CASs) are being developed and fielded to reduce the number and severity of rear-end crashes. Kinematic algorithms within CASs evaluate sensor input and apply assumptions describing human-response timing and deceleration to determine when an alert should be presented. This dissertation presents an analytic assessment of dynamic function and performance CASs and associated driver performance for preventing automotive rear-end crashes. A method for using naturalistic data in the evaluation of CAS algorithms is described and applied to three algorithms. Time-series parametric data collected during 13 rear-end crashes and 70 near-crashes are input into models of collision avoidance algorithms to determine when the alerts would have occurred. Algorithm performance is measured by estimating how much of the driving population would be able to respond in the time available between when an alert would occur and when braking was needed. A sensitivity analysis was performed to consider the effect of alternative inputs into the assessment method. The algorithms were found to warn in sufficient time to permit 50â 70% of the population to avoid collision in similar scenarios. However, the accuracy of this estimate was limited because the tested algorithms were found to alert too frequently to be feasible. The response of the assessment method was most sensitive to differences in assumed response-time distributions and assumed driver braking levels. Low-speed crashes were not addressed by two of the algorithms. Analysis of the events revealed that the necessary avoidance deceleration based on kinematics was generally less than 2 s in duration. At the time of driver response, the time remaining to avoid collision using a 0.5g average deceleration ranged from â 1.1 s to 2.1 s. In 10 of 13 crashes, no driver response deceleration was present. Mean deceleration for the 70 near-crashes was 0.37g and maximum was 0.72g. A set of the events was developed to measure driver response time. The mean driver response time was 0.7 s to begin braking and 1.1 s to reach maximum deceleration. Implications for collision countermeasures are considered, response-time results are compared to previous distributions and future work is discussed.
Ph. D.

APA, Harvard, Vancouver, ISO, and other styles

49

Eriksson, Alexander. "Driver Behaviour in Highly Automated Driving : An evaluation of the effects of traffic, time pressure, cognitive performance and driver attitudes on decision-making time using a web based testing platform." Thesis, Linköpings universitet, Institutionen för datavetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-107119.

Full text

Abstract:

Driverless cars are a hot topic in today’s industry where several vehicle manufacturers try to create a reliable system for automated driving. The advantages of highly automated vehicles are many, safer roads and a lower environmental impact are some of the arguments for this technology. However, the notion of highly automated cars give rise to a large number of human factor issues regarding the safety and reliability of the automated system as well as concern about the driver’s role in the system. The purpose of this study was to explore the effects of systematic variations in traffic complexity and external time pressure on decision-making time in a simulated situation using a web-based testing platform. A secondary focus was to examine whether measures of cognitive performance and driver attitudes have an effect on decision-making time. The results show that systematic variations in both time pressure and traffic complexity have an effect on decision-making time. This indicates that drivers are able to adapt their decision-making to facilitate the requirements of a certain situation. The results also indicate that intelligence; speed of processing and driver attitudes has an effect on decision-making time.

APA, Harvard, Vancouver, ISO, and other styles

50

Grove, Kevin. "Evaluation of Package Delivery Truck Drivers: Task Analysis and Development/Validation of an Objective Visual Behavior Measure to Assess Performance." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/33345.

Full text

Abstract:

The job of a package delivery driver (PDD) is complex and demanding. These drivers must possess many skills in order to succeed in their work, including physical stamina, appropriate decision-making, positive customer interaction, and most importantly, operational safety. Companies must use significant resources, not only to provide insurance for existing drivers, but also to train new drivers to use their visual attention effectively while driving, and companies have a vested interest in ensuring that the most capable trainees are selected for jobs. Currently, subjective assessments of supervisors or managers are typically used to make these determinations. While these are valuable methods for assessing drivers, an objective measure of how well the driver is using his/her visual attention would both assist evaluators in making judgments, as well as make those judgments more accurate. The purpose of the study described herein was to 1) conduct a task analysis of the driving component of the PDD job responsibilities, and 2) create and test an objective measure that a package delivery company could use to evaluate the performance of its drivers. A detailed task analysis based on numerous observations of drivers in their normal work routines was conducted for this research in order to understand these complex tasks. A framework was created for understanding this system of tasks, which was then used to organize all tasks that drivers were observed to perform into more general, goal-oriented activities. Using this task analysis, incidents were identified that were observed while drivers were behind the wheel. This information demonstrated that breakdowns were occurring within the tasks drivers were performing and that improved methods of training and evaluations may be needed as a result. A construct of visual behavior called Head Down Time (HTD) was then created and tested. An individual HDT is defined as the sum of time of all eye gazes away from the primary display (i.e. windshield) between two distinct eye gazes at the primary display while the vehicle is in motion. HDT was evaluated for its ability to differentiate levels of experience between drivers, its relationship to types of route on which drivers delivered, and its relationship to the driving-related incidents that were observed. HDTs were shown to be differed significantly between drivers of low and high experience, with experienced drivers displaying shorter durations of HDT when compared to inexperienced drivers. HDTs also differed in duration when analyzed by the type of route upon which drivers operated. Commercial and urban routes, while not significantly different with respect to HDT, were shown to have increased HDT durations when compared to rural routes and, in turn, residential routes were found to have significantly longer HDTs than did rural routes and may have significantly shorter durations compared to commercial and urban. Finally, HDTs that were associated with observed driving incidents in terms of chronological proximity were shown to be of significantly longer duration than were HDTs that were not associated with incidents. All tests were conducted using appropriate statistical measures, including t-tests at a level of Î± = 0.05 for each dataset. Applications of this research include: 1) improvement of PDD training and evaluation methods through use of a detailed task analysis, 2) improvement in how package delivery companies define incidents and train PDD toward the prevention of incidents based on task analysis and observations as to incident frequency, and 3) the further development of HDT as a possible objective measure to supplement the training and evaluation of PDD.
Master of Science

APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic 'Driver performance'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles