984 resultados para ROAD UTILITY VEHICLE


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This paper examines the effects of an eco-driving message on driver distraction. Two in-vehicle distracter tasks were compared with an eco-driving task and a baseline task in an advanced driving simulator. N = 22 subjects were asked to perform an eco-driving, CD changing, and a navigation task while engaged in critical manoeuvres during which they were expected to respond to a peripheral detection task (PDT) with total duration of 3.5 h. The study involved two sessions over two consecutive days. The results show that drivers’ mental workloads are significantly higher during navigation and CD changing tasks in comparison to the two other scenarios. However, eco-driving mental workload is still marginally significant (p ∼ .05) across different 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. Analysis of the practice effect shows that drivers’ baseline scenario and navigation scenario exhibit significantly less demand on the second day. Drivers also can detect significantly more events on the second day for all scenarios. The authors conclude that even reading a simple message while driving could potentially lead to missing an important event, especially when executing critical manoeuvres. 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 sending text as an eco-driving message analogous to the study circumstances should not be delivered to drivers on-line when vehicle is in motion.

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Motorcyclists in Australia have been found to be 30 times more likely to be killed per kilometre travelled than car occupants and 40 times more likely to be seriously injured. One approach to preventing motorcycle-related injury is through training and education. While there is traditionally a major focus on developing riding skills during training for motorcyclists, there is also a need for training to promote safe riding to reduce subsequent risk taking. The Transtheoretical Model, commonly known as the ‘Stages of Change’ model, provides a rationale to support incremental behaviour change for risky riding that may be facilitated through motorcycle rider training and education. A sample of 438 learner motorcyclists attended a rider training program in Queensland, Australia, with the stages of change to adopt a safe riding mindset and safe riding practices being measured upon commencement of the course (Time 1) and then again upon completion (Time 2). A small subset of the original sample (n=45) responded at follow up 24 months post training (Time 3). Consistent with the aims of training, results showed a significant shift from the contemplation stage to the subsequent stages of change for participants between Time 1 and Time 2. Progression to the later stages in the model was found for the subset of participants that responded at the Time 3 follow up. Issues of questionnaire design and the utility of the Transtheoretical Model for motorcycle rider training are discussed.

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Dealing with the aggression of other drivers on the road is an important skill given that driving is a common activity for adults in highly motorised countries. Even though incidents of extreme aggression on the road (such as assault) are reportedly rare, milder forms, some of them dangerous (such as tailgating or deliberately following too closely) are apparently common, and may be increasing. At the very least, this is likely to render the driving environment more stressful, and at worst elevates the risk of crashing by increasing both the level of risky driving behaviours and the likelihood of responses that escalate the situation. Thus the need for drivers to manage incidents of conflict is likely to become increasingly important. However, little research examines how drivers manage their own or others’ aggressive driving behaviour. Recently greater attention has been paid to driver cognitions, especially the attributions that drivers make about other drivers, that then might influence their own driving responses, particularly aggressive or risky ones. The study reported below was the first in a larger exploration of aggressive driving that focussed on driver cognitions, emotions and underlying motivations for aggressive behaviours on the road. Qualitative, in-depth interviews of drivers (n = 30, aged 18-49 years) were subjected to thematic analysis to investigate driver experiences with aggressive driving. Two main themes were identified from these accounts: driver management of self; and driver attempts to influence or manage other drivers. This paper describes the subthemes falling under the management of self main theme. These subthemes were labelled ‘being magnanimous’, ‘chilling out’, ‘slowing down’, and ‘apology/acknowledgment’. ‘Being magnanimous’ referred to situations where the respondent perceived him/herself to be a recipient of another’s aggressive driving and made a deliberate choice not to respond. However, a characteristic of this sub-theme was that this choice was underpinned by the adoption of morally superior stance, or sense of magnanimity. ‘Chilling out’ was a more general response to both the milder aggressive behaviours of other drivers and the general frustrations of driving. ‘Slowing down’ referred to reducing one’s speed in response to the perceived aggressive driving, often tailgating, of another. This subtheme appeared to consist of two separate underlying motivations. One of these was a genuine concern for one’s own safety while the other was more aimed at “getting back” at the other driver. ‘Apology’ referred to how drivers modified their more negative reactions and responses when another driver made gestures that acknowledged their having made a mistake, indicated an apology, or acknowledged the recipient driver. These sub-themes are discussed in relation to their implications for understanding aggressive driving and intervening to reduce it.

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As part of an evaluation of the 2010 legislation for child vehicle occupants in Queensland, road-side observations of private passenger vehicles were used to estimate the proportions of children 0-under 7 years travelling in each of the 5 different restraint types (eg. forward facing child restraint). Data was collected in 4 major population centres: Brisbane, Sunshine Coast, Mackay and Townsville. Almost all children were restrained (95.1%, 95% CI 94.3-95.9%), with only 3.3% (95% CI 2.6-4.0%) clearly unrestrained and 44 (1.6%, 95% CI 1.1-2.1%) for whom restraint status could not be determined (‘unknown’). However, around 24.0% (95 CI 21.8-26.2%) of the target-aged children were deemed inappropriately restrained, primarily comprised of 3-6 year olds in seatbelts (18.7% of the 0-6 year olds, 95% CI 16.3-21.1%) or unrestrained (3.7% of the 0-6 year olds, 95% CI 2.5-4.9%) instead of booster seats. In addition, compliance appeared significantly lower for some regional locations where the proportion of children observed as completely unrestrained was relatively high and of concern

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The research study discussed in the paper investigated the influence of organic matter on heavy metal adsorption for different particle size ranges of build-up solids. Samples collected from road surfaces were assessed for organic matter content, mineral composition, particle size distribution and effective cation exchange capacity. It was found that the organic matter plays a key role in >75µm particles in the adsorption of Zinc, Lead, Nickel and Copper, which are generated by traffic activities. Clay forming minerals and metal oxides of Iron, Aluminium and Manganese was found to be important for heavy metal adsorption to <75µm particles. It was also found that heavy metals adsorbed to organic matter are strongly bound to particles and these metal ions will not be bio-available if the chemical quality of the media remains stable.

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In microscopic traffic simulators, the interaction between vehicles is considered. The dynamics of the system then becomes an emergent property of the interaction between its components. Such interactions include lane-changing, car-following behaviours and intersection management. Although, in some cases, such simulators produce realistic prediction, they do not allow for an important aspect of the dynamics, that is, the driver-vehicle interaction. This paper introduces a physically sound vehicle-driver model for realistic microscopic simulation. By building a nanoscopic traffic simulation model that uses steering angle and throttle position as parameters, the model aims to overcome unrealistic acceleration and deceleration values, as found in various microscopic simulation tools. A physics engine calculates the driving force of the vehicle, and the preliminary results presented here, show that, through a realistic driver-vehicle-environment simulator, it becomes possible to model realistic driver and vehicle behaviours in a traffic simulation.

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Road safety barriers are used to minimise the severity of road accidents and protect lives and property. There are several types of barrier in use today. This paper reports the initial phase of research carried out to study the impact response of portable water-filled barrier (PWFB) which has the potential to absorb impact energy and hence provide crash mitigation under low to moderate speeds. Current research on the impact and energy absorption capacity of water-filled road safety barriers is limited due to the complexity of fluid-structure interaction under dynamic impact. In this paper, a novel fluid-structure interaction method is developed based on the combination of Smooth Particle Hydrodynamics (SPH) and Finite Element Method (FEM). The sloshing phenomenon of water inside a PWFB is investigated to explore the energy absorption capacity of water under dynamic impact. It was found that water plays an important role in energy absorption. The coupling analysis developed in this paper will provide a platform to further the research in optimising the behaviour of the PWFB. The effect of the amount of water on its energy absorption capacity is investigated and the results have practical applications in the design of PWFBs.

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Road traffic accidents can be reduced by providing early warning to drivers through wireless ad hoc networks. When a vehicle detects an event that may lead to an imminent accident, the vehicle disseminates emergency messages to alert other vehicles that may be endangered by the accident. In many existing broadcast-based dissemination schemes, emergency messages may be sent to a large number of vehicles in the area and can be propagated to only one direction. This paper presents a more efficient context aware multicast protocol that disseminates messages only to endangered vehicles that may be affected by the emergency event. The endangered vehicles can be identified by calculating the interaction among vehicles based on their motion properties. To ensure fast delivery, the dissemination follows a routing path obtained by computing a minimum delay tree. The multicast protocol uses a generalized approach that can support any arbitrary road topology. The performance of the multicast protocol is compared with existing broadcast protocols by simulating chain collision accidents on a typical highway. Simulation results show that the multicast protocol outperforms the other protocols in terms of reliability, efficiency, and latency.

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Vehicular safety applications, such as cooperative collision warning systems, rely on beaconing to provide situational awareness that is needed to predict and therefore to avoid possible collisions. Beaconing is the continual exchange of vehicle motion-state information, such as position, speed, and heading, which enables each vehicle to track its neighboring vehicles in real time. This work presents a context-aware adaptive beaconing scheme that dynamically adapts the beaconing repetition rate based on an estimated channel load and the danger severity of the interactions among vehicles. The safety, efficiency, and scalability of the new scheme is evaluated by simulating vehicle collisions caused by inattentive drivers under various road traffic densities. Simulation results show that the new scheme is more efficient and scalable, and is able to improve safety better than the existing non-adaptive and adaptive rate schemes.

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There is consistent evidence showing that driver behaviour contributes to crashes and near miss incidents at railway level crossings (RLXs). The development of emerging Vehicle-to-Vehicle and Vehicle-to-Infrastructure technologies is a highly promising approach to improve RLX safety. To date, research has not evaluated comprehensively the potential effects of such technologies on driving behaviour at RLXs. This paper presents an on-going research programme assessing the impacts of such new technologies on human factors and drivers’ situational awareness at RLX. Additionally, requirements for the design of such promising technologies and ways to display safety information to drivers were systematically reviewed. Finally, a methodology which comprehensively assesses the effects of in-vehicle and road-based interventions warning the driver of incoming trains at RLXs is discussed, with a focus on both benefits and potential negative behavioural adaptations. The methodology is designed for implementation in a driving simulator and covers compliance, control of the vehicle, distraction, mental workload and drivers’ acceptance. This study has the potential to provide a broad understanding of the effects of deploying new in-vehicle and road-based technologies at RLXs and hence inform policy makers on safety improvements planning for RLX.

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Recent efforts in mission planning for underwater vehicles have utilised predictive models to aid in navigation, optimal path planning and drive opportunistic sampling. Although these models provide information at a unprecedented resolutions and have proven to increase accuracy and effectiveness in multiple campaigns, most are deterministic in nature. Thus, predictions cannot be incorporated into probabilistic planning frameworks, nor do they provide any metric on the variance or confidence of the output variables. In this paper, we provide an initial investigation into determining the confidence of ocean model predictions based on the results of multiple field deployments of two autonomous underwater vehicles. For multiple missions conducted over a two-month period in 2011, we compare actual vehicle executions to simulations of the same missions through the Regional Ocean Modeling System in an ocean region off the coast of southern California. This comparison provides a qualitative analysis of the current velocity predictions for areas within the selected deployment region. Ultimately, we present a spatial heat-map of the correlation between the ocean model predictions and the actual mission executions. Knowing where the model provides unreliable predictions can be incorporated into planners to increase the utility and application of the deterministic estimations.

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The research study discussed in the paper investigated the adsorption/desorption behaviour of heavy metals commonly deposited on urban road surfaces, namely, Zn, Cu, Cr and Pb for different particle size ranges of solids. The study outcomes, based on field studies and batch experiments confirmed that road deposited solids particles contain a significantly high amount of vacant charge sites with the potential to adsorb additional heavy metals. Kinetic study and adsorption experiments indicated that Cr is the most preferred metal element to associate with solids due to the relatively high electro negativity and high charge density of trivalent cation (Cr3+). However, the relatively low availability of Cr in the urban road environment could influence this behaviour. Comparing total adsorbed metals present in solids particles, it was found that Zn has the highest capacity for adsorption to solids. Desorption experiments confirmed that a low concentration of Cu, Cr and Pb in solids was present in water-soluble and exchangeable form, whilst a significant fraction of adsorbed Zn has a high likelihood of being released back into solution. Among heavy metals, Zn is considered to be the most commonly available metal among road surface pollutants.

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Dhaka, Bangladesh faces chronic traffic congestion Funding for major infrastructure proves challenging This research is investigating feasibility of adopting: -Road Pricing -with significant Bus Rapid Transit (BRT) project

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Tourist use of mopeds in Queensland is encouraged by licensing regulations permitting moped riding for car licence holders, who may lack prior knowledge or experience of moped or motorcycle use. Using official crash and registration data, this research examines moped use by tourists, identified as crash-involved riders holding an interstate or overseas licence. Tourists were more likely to be younger, female, in single vehicle crashes, and deemed at fault than Queensland licence holders. Potential safety issues include poor riding skills, inexperience, inattention and lack of protective clothing. Moped rental companies play an important role in managing client crash and injury risks. These risks could also be reduced through introduction of more stringent licensing requirements, though this may be detrimental to moped rental companies as well as to tourist mobility and enjoyment. The discussion considers the relevance of adventure tourism perspectives and theory to the use of mopeds by tourists.

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Background:  For those in the field of managing diabetic complications, the accurate diagnosis and monitoring of diabetic peripheral neuropathy (DPN) continues to be a challenge. Assessment of sub-basal corneal nerve morphology has recently shown promise as a novel ophthalmic marker for the detection of DPN. Methods:  Two hundred and thirty-one individuals with diabetes with predominantly mild or no neuropathy and 61 controls underwent evaluation of diabetic neuropathy symptom score, neuropathy disability score, testing with 10 g monofilament, quantitative sensory testing (warm, cold, vibration detection) and nerve conduction studies. Corneal nerve fibre length, branch density and tortuosity were measured using corneal confocal microscopy. Differences in corneal nerve morphology between individuals with and without DPN and controls were investigated using analysis of variance and correlations were determined between corneal morphology and established tests of, and risk factors for, DPN. Results:  Corneal nerve fibre length was significantly reduced in diabetic individuals with mild DPN compared with both controls (p < 0.001) and diabetic individuals without DPN (p = 0.012). Corneal nerve branch density was significantly reduced in individuals with mild DPN compared with controls (p = 0.032). Corneal nerve fibre tortuosity did not show significant differences. Corneal nerve fibre length and corneal nerve branch density showed modest correlations to most measures of neuropathy, with the strongest correlations to nerve conduction study parameters (r = 0.15 to 0.25). Corneal nerve fibre tortuosity showed only a weak correlation to the vibration detection threshold. Corneal nerve fibre length was inversely correlated to glycated haemoglobin (r = -0.24) and duration of diabetes (r = -0.20). Conclusion:  Assessment of corneal nerve morphology is a non-invasive, rapid test capable of showing differences between individuals with and without DPN. Corneal nerve fibre length shows the strongest associations with other diagnostic tests of neuropathy and with established risk factors for neuropathy.