205 resultados para Driver errors.
Resumo:
A number of tests and test batteries are available for the prediction of older driver safety, but many of these have not been validated against standardized driving outcome measures. The aim of this study was to evaluate a series of previously described screening tests in terms of their ability to predict the potential for safe and unsafe driving. Participants included 79 community-dwelling older drivers (M=72.16 years, SD=5.46; range 65-88 years; 57 males and 22 females) who completed a previously validated multi-disciplinary driving assessment, a hazard perception test, a hazard change detection test and a battery of vision and cognitive tests. Participants also completed a standardized on-road driving assessment. The multi-disciplinary test battery had the highest predictive ability with a sensitivity of 80% and a specificity of 73%, followed by the hazard perception test which demonstrated a sensitivity of 75% and a specificity of 61%. These findings suggest that a relatively simple and practical battery of tests from a range of domains has the capacity to predict safe and unsafe driving in older adults.
Resumo:
This research project examined objective measures of driver behaviour and road users' perceptions on the usefulness and effectiveness of three specific VMS (Variable Message Signs) interventions to improve speeding and headway behaviours. The interventions addressed speeding behaviour alone (intervention 1), headway behaviour alone (intervention 2) and a combination of speeding and headway behaviour (intervention 3). Six VMS were installed along a segment of the Bruce Highway, with a series of three signs for each of the northbound and southbound traffic. Speeds and headway distances were measured with loop detectors installed before and after each VMS. Messages addressing speeding and headway were devised for display on the VMS. A driver could receive a message if they were detected as exceeding the posted speed limit (of 90km/hr) or if the distance to the vehicle in front was less than 2.0s. In addition to the on-road objective measurement of speeding and headway behaviours, the research project elicited self-reported responses to the speeding and headway messages from a sample of drivers via a community-based survey. The survey sought to examine the drivers' beliefs about the effectiveness of the signs and messages, and their views about the role, use, and effectiveness of VMS more generally.
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The Queensland graduated driver licensing (GDL) context (post-July 2007) - The experiences of young Learner drivers - Comparison of pre- (‘Original-GDL’) and post-July 2007 (‘Enhanced-GDL’) experiences - Post-July 2007 experiences - GDL-related issues - Other factors in young novice driver safety - Person-related factors - Social factors
Resumo:
- Young novice drivers - The Queensland graduated driver licensing (GDL) context - Pre-July 2007 (‘Original-GDL’) - Post-July 2007 (‘Enhanced-GDL’) - Experiences of Learners in Queensland’s enhanced-GDL program - Pre-/post-July 2007 comparison - Post-July 2007 only - Implications - Strengths and limitations
Resumo:
A significant issue encountered when fusing data received from multiple sensors is the accuracy of the timestamp associated with each piece of data. This is particularly important in applications such as Simultaneous Localisation and Mapping (SLAM) where vehicle velocity forms an important part of the mapping algorithms; on fastmoving vehicles, even millisecond inconsistencies in data timestamping can produce errors which need to be compensated for. The timestamping problem is compounded in a robot swarm environment due to the use of non-deterministic readily-available hardware (such as 802.11-based wireless) and inaccurate clock synchronisation protocols (such as Network Time Protocol (NTP)). As a result, the synchronisation of the clocks between robots can be out by tens-to-hundreds of milliseconds making correlation of data difficult and preventing the possibility of the units performing synchronised actions such as triggering cameras or intricate swarm manoeuvres. In this thesis, a complete data fusion unit is designed, implemented and tested. The unit, named BabelFuse, is able to accept sensor data from a number of low-speed communication buses (such as RS232, RS485 and CAN Bus) and also timestamp events that occur on General Purpose Input/Output (GPIO) pins referencing a submillisecondaccurate wirelessly-distributed "global" clock signal. In addition to its timestamping capabilities, it can also be used to trigger an attached camera at a predefined start time and frame rate. This functionality enables the creation of a wirelessly-synchronised distributed image acquisition system over a large geographic area; a real world application for this functionality is the creation of a platform to facilitate wirelessly-distributed 3D stereoscopic vision. A ‘best-practice’ design methodology is adopted within the project to ensure the final system operates according to its requirements. Initially, requirements are generated from which a high-level architecture is distilled. This architecture is then converted into a hardware specification and low-level design, which is then manufactured. The manufactured hardware is then verified to ensure it operates as designed and firmware and Linux Operating System (OS) drivers are written to provide the features and connectivity required of the system. Finally, integration testing is performed to ensure the unit functions as per its requirements. The BabelFuse System comprises of a single Grand Master unit which is responsible for maintaining the absolute value of the "global" clock. Slave nodes then determine their local clock o.set from that of the Grand Master via synchronisation events which occur multiple times per-second. The mechanism used for synchronising the clocks between the boards wirelessly makes use of specific hardware and a firmware protocol based on elements of the IEEE-1588 Precision Time Protocol (PTP). With the key requirement of the system being submillisecond-accurate clock synchronisation (as a basis for timestamping and camera triggering), automated testing is carried out to monitor the o.sets between each Slave and the Grand Master over time. A common strobe pulse is also sent to each unit for timestamping; the correlation between the timestamps of the di.erent units is used to validate the clock o.set results. Analysis of the automated test results show that the BabelFuse units are almost threemagnitudes more accurate than their requirement; clocks of the Slave and Grand Master units do not di.er by more than three microseconds over a running time of six hours and the mean clock o.set of Slaves to the Grand Master is less-than one microsecond. The common strobe pulse used to verify the clock o.set data yields a positive result with a maximum variation between units of less-than two microseconds and a mean value of less-than one microsecond. The camera triggering functionality is verified by connecting the trigger pulse output of each board to a four-channel digital oscilloscope and setting each unit to output a 100Hz periodic pulse with a common start time. The resulting waveform shows a maximum variation between the rising-edges of the pulses of approximately 39¥ìs, well below its target of 1ms.
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Social harmony can manifest in many ways. In rapidly motorizing countries like China, a growing area of potential disharmony is road use. The increased ability to purchase a car for the first time and a subsequent increase in new drivers has seen several Chinese cities take unprecedented measures to manage congestion. There is a corresponding need to ensure effective traffic law enforcement in promoting a safe environment for all road users. This paper reports qualitative research conducted with Beijing car drivers to investigate perceptions of unsafe road use, penalties for traffic violations, and improvements for the current system. Overall, the findings suggest awareness among drivers of many of the key risk factors. A perceived lack of clarity in how penalties are determined was identified and drivers in-dicated a desire to know how revenue from traffic fines is used. Several suggestions for improving the current system included school/community education about road risks and traffic law. The rise of private car ownership in China may contribute to a more harmonious personal life, but at the same time, may contribute to a decrease in societal harmony. A major challenge for authorities in any country is to promote the idea of a collective responsibility for road safety (traffic harmony), especially to those who perceive that traffic rules do not apply to them. This is a potentially greater challenge for China as it strives to balance harmony on the road and harmony in the broader society.
Resumo:
Road crashes are one of the most significant public health problems in Pakistan; however the factors that contribute to road crashes in Pakistan are not well-researched. Traditional beliefs and values can act as a barrier to health-promoting and injury prevention behaviours, in general and especially in relation to road safety, and may also contribute to risk-taking behaviours. Such beliefs can present significant challenges for health advocates who aim to change behaviour in order to avert road crashes and diminish their consequences. Qualitative research was undertaken in Islamabad, Rawalpindi and Lahore with a range of drivers, religious orators, police and policy makers to explore cultural and religious beliefs and their association with risky road use, and to understand how they might affect development of road safety interventions. The findings highlight a range of issues, including the identification of aspects of beliefs that have complex social implications when designing safety intervention strategies. The pervasive nature of religious and superstitious beliefs in Pakistan can affect road user behaviour by reinforcing the presumption that the individual has no part to play in safety, thereby supporting continued risk taking behaviour. It is anticipated that the findings could be used to inform the design of interventions aimed at influencing broad-spectrum health attitudes and practices among the communities where such beliefs are prevalent.
Resumo:
Reporting of medication administration errors (MAEs) is one means by which health care facilities monitor their practice in an attempt to maintain the safest patient environment. This study examined the likelihood of registered nurses (RNs) reporting MAEs when working in Saudi Arabia. It also attempted to identify potential barriers in the reporting of MAE. This study found that 63% of RNs raised concerns about reporting of MAEs in Saudi Arabia—nursing administration was the largest impediment affecting nurses' willingness to report MAEs. Changing attitude to a non-blame system and implementation of anonymous reporting systems may encourage a greater reporting of MAEs.
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The future emergence of many types of airborne vehicles and unpiloted aircraft in the national airspace means collision avoidance is of primary concern in an uncooperative airspace environment. The ability to replicate a pilot’s see and avoid capability using cameras coupled with vision based avoidance control is an important part of an overall collision avoidance strategy. But unfortunately without range collision avoidance has no direct way to guarantee a level of safety. Collision scenario flight tests with two aircraft and a monocular camera threat detection and tracking system were used to study the accuracy of image-derived angle measurements. The effect of image-derived angle errors on reactive vision-based avoidance performance was then studied by simulation. The results show that whilst large angle measurement errors can significantly affect minimum ranging characteristics across a variety of initial conditions and closing speeds, the minimum range is always bounded and a collision never occurs.
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• Car-bicycle and car-motorcycle crashes often serious • Car driver mostly at fault, often because of failure to see (Schramm et al, 2010) • Car drivers with motorcycling experience less likely to be involved in motorcycle crashes or be at fault (Brooks & Guppy, 1990; Magazzu et al., 2006) and hold more positive beliefs about motorcyclists (Crundall et al., 2008) • Does bicycle riding experience have the same benefits?
Resumo:
Principal Topic Counties in Northern Europe, such as Sweden, Finland and Denmark, have comparatively low per capita rates of entrepreneurship as measured by independent new venture start-up rates – as for example measured by the Global Entrepreneurship Monitor (GEM) Total entrepreneurial activity (TEA) rate. However, the latest 2011 GEM data reveals that these same countries have comparatively very high Employee Entrepreneurship Activity (EEA) rates – that is a high rate per capita of employees involved in new product development or new enterprise activities. This observation has prompted us to investigate the role of national culture in driving independent versus employee entrepreneurial activities. Prior research has established that national (and regional) culture plays an important role in forming an “entrepreneurial culture” that encourages (or discourages) independent business start-ups and TEA (e.g. Davidsson, 1995; Beugelsdijk, 2007). However, the relationship of culture and EEA has not received research attention. Moreover, empirical relationships between elements of national culture and independent entrepreneurship have revealed some surprising results. For example, Wildeman et al. (1999) report an unexpected higher share of individual business ownership in countries that have higher uncertainty avoidance, higher power distance and lower individualism according to Hofstede’s dimensions of culture. They speculate that dissatisfaction can be a source of entrepreneurship: in countries with a high power distance, a high uncertainty avoidance and low individualism, there may be relatively more business owners since enterprising individuals cannot satisfy their needs within existing organizations. Yet it remains a rather open question whether entrepreneurial behaviour in existing organisations provides a satisfactory explanation for these empirical findings. Methods We will conduct a cross sectional study of the influence of national culture according to the five / six dimensions of Hofstede (1980; 2001) on both TEA and EEA for the 54 countries that participated in GEM 2011. Since it is well established that the opportunities for entrepreneurship vary substantially with a country’s level of economic development, we intend to conduct separate analyses for the three categories of development – innovation driven economies, efficient driven economies and factor driven economies. We also intend to restrict our assessment of TEA to opportunity driven entrepreneurship, as necessity driven entrepreneurship has a different relationship to the “entrepreneurial culture” that is the focus of our study. We will control for a range of factors such as GDP growth, ease of doing business index and unemployment. Results and Implications Descriptive analyses of the GEM TEA and EEA data reveal clusters of countries that appear to be have similar national culture. We are yet to conduct regression analyses.
Resumo:
Driver distraction has recently been defined by Regan as "the diversion of attention away from activities critical for safe driving toward a competing activity, which may result in insufficient or no attention to activities critical for safe driving (Regan, Hallett & Gordon, 2011, p.1780)". One source of distraction is in-vehicle devices, even though they might provide other benefits, e.g. navigation systems. Currently, eco-driving systems have been growing rapidly in popularity. These systems send messages to drivers so that driving performance can be improved in terms of fuel efficiency. However, there remain unanswered questions about whether eco-driving systems endanger drivers by distracting them. In this research, the CARRS-Q advanced driving simulator was used in order to provide safety for participants and meanwhile simulate real world driving. The distraction effects of tasks involving three different in-vehicle systems were investigated: changing a CD, entering a five digit number as a part of navigation task and responding to an eco-driving task. Driving in these scenarios was compared with driving in the absence of these distractions, and while drivers engaged in critical manoeuvres. In order to account for practice effects, the same scenarios were duplicated on a second day. The three in-vehicle systems were not the exact facsimiles of any particular existing system, but were designed to have similar characteristics to those of system available. In general, the results show that drivers’ mental workloads are significantly higher in navigation and CD changing scenarios in comparison to the two other scenarios, which implies that these two tasks impose more visual/manual and cognitive demands. However, eco-driving mental workload is still high enough to be called marginally significant (p ~ .05) across manoeuvres. Similarly, event detection tasks show that drivers miss significantly more events in the navigation and CD changing scenarios in comparison to both the baseline and eco-driving scenario across manoeuvres. Analysis of the practice effect shows that drivers’ baseline scenario and navigation scenario exhibit significantly less demand on the second day. However, the number of missed events across manoeuvres confirmed that drivers can detect significantly more events on the second day for all scenarios. Distraction was also examined separately for five groups of manoeuvres (straight, lane changing, overtaking, braking for intersections and braking for roundabouts), in two locations for each condition. Repeated measures mixed ANOVA results show that reading an eco-driving message can potentially impair driving performance. When comparing the three in–vehicle distractions tested, attending to an eco-driving message is similar in effect to the CD changing task. The navigation task degraded driver performance much more than these other sources of distraction. In lane changing manoeuvres, drivers’ missed response counts degraded when they engaged in reading eco-driving messages at the first location. However, drivers’ event detection abilities deteriorated less at the second lane changing location. In baseline manoeuvres (driving straight), participants’ mean minimum speed degraded more in the CD changing scenario. Drivers’ lateral position shifted more in both CD changing and navigation tasks in comparison with both eco-driving and baseline scenarios, so they were more visually distracting. Participants were better at event detection in baseline manoeuvres in comparison with other manoeuvres. When approaching an intersection, the navigation task caused more events to be missed by participants, whereas eco-driving messages seemed to make drivers less distracted. The eco-driving message scenario was significantly less distracting than the navigation system scenario (fewer missed responses) when participants commenced braking for roundabouts. To sum up, in spite of the finding that two other in-vehicle tasks are more distracting than the eco-driving task, the results indicate that even reading a simple message while driving could potentially lead to missing an important event, especially when executing critical manoeuvres. This suggests that in-vehicle eco-driving systems have the potential to contribute to increased crash risk through distraction. However, there is some evidence of a practice effect which suggests that future research should focus on performance with habitual rather than novel tasks. It is recommended that eco-driving messages be delivered to drivers off-line when possible.
Resumo:
This paper describes the development and validation of a PC based MUARC Driver Distraction Test designed to measure simulated driving performance while the driver is performing a secondary task. The paper discusses the logic behind the development of the test, including the principles that were used to guide its design, as well as the results of a pilot validation study. The findings from this study were consistent with previous research and theory and were consistent with those obtained with the LCT. The results did, however, highlight a number of refinements that were necessary to improve the utility of the test.