145 resultados para 090205 Hybrid Vehicles and Powertrains


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Graduated licensing has been identified as the most promising approach to reducing the crash risk of novice drivers. However, research suggests that the effectiveness of graduated licensing appears to differ between urban and rural novice drivers and according to race or ethnicity. Extensive supervised driving practice as a learner driver is an important component of graduated licensing systems in Australia and many other countries. Earlier CARRS-Q research identified that falsification of logbooks was more common among particular demographic groups. The factors underlying this are not well understood. It is unclear whether this reflects a lack of understanding of the importance of supervised practice (given that it is not a licensing requirement in many countries of origin), or it reflects lack of access to vehicles and supervising drivers, or whether there is less respect for driver licensing requirements among some groups. It is possible that the importance of these factors may differ across ethnic groups, depending on socioeconomic factors and cultural attitudes to road safety. In an attempt to better understand these issues, this study presents some preliminary results of focus groups examining the experience of the Queensland Graduated Driver Licensing System by Korean-Australian novice drivers and their parents.

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Background In China, as in many developing countries, rapid increases in car ownership and new drivers have been coupled with a large trauma burden. The World Health Organization has identified key risk factors including speeding, drink-driving, helmet and restraint non-use, overloaded vehicles, and fatigued-driving in many rapidly motorising countries, including China. Levels of awareness of these risk factors among road users are not well understood. Although research identifies speeding as the major factor contributing to road crashes in China, there appears to be widespread acceptance of it among the broader community. Purpose To assess self-reported speeding and awareness of crash risk factors among Chinese drivers in Beijing. Methods Car drivers (n=299) were recruited from car washing locations and car parks to complete an anonymous questionnaire. Perceptions of the relative risk of drink-driving, fatigued-driving and speeding, and attitudes towards speeding and self-reported driving speeds were assessed. Results Overall, driving speeds of >10km/hr above posted limits on two road types (60 and 80 km/hour zones) were reported by more than one third of drivers. High-range speeding (i.e., >30 km/hour in a 60 km/hour zone and >40 km/hour in an 80 km/hour zone) was reported by approximately 5% of the sample. Attitudinal measures indicated that approximately three quarters of drivers reported attitudes that were not supportive of speeding. Drink-driving was identified as the most risky behaviour; 18% reported the perception that drink-driving had the same level of danger as speeding and 82% reported it as more dangerous. For fatigued-driving, 1% reported the perception that it was not as dangerous as speeding; 27.4% reported it as the same level and 71.6% perceived it as more dangerous. Conclusion Driving speeds well above posted speed limits were commonly reported by drivers. Speeding was rated as the least dangerous on-road behaviour, compared to drink-driving and fatigued-driving. One third of drivers reported regularly engaging in speeds at least 10km/hr above posted limits, despite speeding being the major reported contributor to crashes. Greater awareness of the risks associated with speeding is needed to help reduce the road trauma burden in China and promote greater speed limit compliance.

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One of the concerns about the use of Bluetooth MAC Scanner (BMS) data, especially from urban arterial, is the bias in the travel time estimates from multiple Bluetooth devices being transported by a vehicle. For instance, if a bus is transporting 20 passengers with Bluetooth equipped mobile phones, then the discovery of these mobile phones by BMS will be considered as 20 different vehicles, and the average travel time along the corridor estimated from the BMS data will be biased with the travel time from the bus. This paper integrates Bus Vehicle Identification system with BMS network to empirically evaluate such bias, if any. The paper also reports an interesting finding on the uniqueness of MAC IDs.

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Transition zones between bridge decks and rail tracks suffer early failure due to poor interaction between rail vehicles and sudden changes of stiffness. This has been an ongoing problem to rail industry and yet still no systematic studies appear to have been taken to maintain a gradually smoothening transmission of forces between the bridge and its approach. Differential settlement between the bridge deck and rail track in the transition zone is the fundamental issue, which negatively impacts the rail industry by causing passenger discomfort, early damage to infrastructure and vehicle components, speed reduction, and frequent maintenance cycles. Identification of mechanism of the track degradation and factors affecting is imperative to design any mitigation method for reducing track degradation rate at the bridge transition zone. Unfortunately this issue is still not well understood, after conducting a numbers of reviews to evaluate the key causes, and introducing a wide range of mitigation techniques. In this study, a comprehensive analysis of the available literature has been carried out to develop either a novel design framework or a mitigation technique for the bridge transition zone. This paper addresses three critical questions in relation to the track degradation at transition zone: (1) what are the causes of bridge transition track degradation?; (2) what are the available mitigation techniques in reducing the track degradation rate?; (3) what are the factors affecting on poor performance of the existing mitigation techniques?. It is found that the absence of soil-water response, dynamic loading response, and behaviour of geotechnical characteristics under long-term conditions in existing track transition design frameworks critically influence on the failures of existing mitigation techniques. This paper also evaluates some of the existing design frameworks to identify how each design framework addresses the track degradation at the bridge transition zone.

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We describe the X-series impulse facilities at The University of Queensland and show that they can produce useful high speed flows of relevance to the study of high temperature radiating flow flields characteristic of atmospheric entry. Two modes of operation are discussed: (a) the expansion tube mode which is useful for subscale aerodynamic testing of vehicles and (b) the non-reflected shock tube mode which can be used to emulate the nonequilibrium radiating region immediately following the bow shock of a flight vehicle.

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Marine craft (surface vessels, underwater vehicles, and offshore rigs) perform operations that require tight motion control. During the past three decades, there has been an increasing demand for higher accuracy and reliability of marinecraft motion control systems. Today, these control systems are an enabling factor for single and multicraft marine operations. This chapter provides an overview of the main characteristics and design aspects of motion control systems for marine craft. In particular, we discuss the architecture of the control system, the functionality of its main components, the characteristics of environmental disturbances, control objectives, and essential aspects of modeling and motion control design.

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Portable water-filled barriers (PWFBs) are roadside appurtenances that prevent vehicles from penetrating into temporary construction zones on roadways. PWFBs are required to satisfy the strict regulations for vehicle re-direction in tests. However, many of the current PWFBs fail to re-direct the vehicle at high speeds due to the inability of the joints to provide appropriate stiffness. The joint mechanism hence plays a crucial role in the performance of a PWFB system at high speed impacts. This paper investigates the desired features of the joint mechanism in a PWFB system that can re-direct vehicles at high speeds, while limiting the lateral displacement to acceptable limits. A rectangular “wall” representative of a 30 m long barrier system was modeled and a novel method of joining adjacent road barriers was introduced through appropriate pin-joint connections. The impact response of the barrier “wall” and the vehicle was obtained and the results show that a rotational stiffness of 3000 kNm/rad at the joints seems to provide the desired features of the PWFB system to re-direct impacting vehicles and restrict the lateral deflection. These research findings will be useful to safety engineers and road barrier designers in developing a new generation of PWFBs for increased road safety.

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University–community engagement (UCE) represents a hybrid discourse and a set of practices within contemporary higher education. As a modality of research and teaching, ‘engagement’ denotes the process of universities forming partnerships with external communities for the promised generation of mutually beneficial and socially responsive knowledge, leading to enhanced economic, social and cultural developments. A critical discourse analysis (Fairclough 2003. Analysing Discourse: Textual analysis for social research. London: Routledge) of the Australian Universities Community Engagement Alliance’s (AUCEA) ‘Position Paper’(2008 Universities and community engagement (Position paper 2008–2010)), as reported in this article, suggests that its uneasy synthesis of neoliberal, social inclusion and civic engagement discourses into a hybrid UCE discourse semantically privileges neoliberal forms of engagement. Perhaps, as a result, the AUCEA seems to have missed an opportunity to influence the Australian ‘widening participation’ debate on securing access and opportunity for marginalised students at universities and building social and cultural capital within their communities of origin.

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The primary goal in hard tissue engineering is to combine high-performance scaffold materials with living cells to develop biologically active substitutes that can restore tissue functions. This requires relevant knowledge in multidisciplinary fields encompassing chemical engineering, material science, chemistry, biology and nanotechnology. Here we present an overview on the recent progress of how two representative carbon nanostructures, namely, carbon nanotubes and graphene, aid and advance the research in hard tissue engineering. The article focuses on the advantages and challenges of integrating these carbon nanostructures into functional scaffolds for repairing and regenerative purposes. It includes, but is not limited to, the critical physico-chemical properties of carbon nanomaterials for enhanced cell interactions such as adhesion, morphogenesis, proliferation and differentiation; the novel designs of two- and three-dimensional nanostructured scaffolds; multifunctional hybrid materials; and the biocompatible aspects of carbon nanotubes and graphene. Perspectives on the future research directions are also given, in an attempt to shed light on the innovative and rational design of more effective biomedical devices in hard tissue engineering.

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Combustion sources are well-known sources of electrical ions (Howard, J.B. et al. 1973). Motor vehicles emissions are one of the main sources of ions in urban environments. The presence of charged particles in motor vehicle emissions has been known for many years (Kittelson, 1986; Yu et al, 2004; Jung and Kittelson, 2005). Although these particles are probably charged by the attachment of air ions, there is very little information on the nature, sign and magnitude of the small ions (diameter < 1.6 nm) emitted by motor vehicles and/or present by the sides of roads.

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Poor compliance with speed limits is a serious safety concern in work zones. Most studies of work zone speeds have focused on descriptive analyses and statistical testing without systematically capturing the effects of vehicle and traffic characteristics. Consequently, little is known about how the characteristics of surrounding traffic and platoons influence speeds. This paper develops a Tobit regression technique for innovatively modeling the probability and the magnitude of non-compliance with speed limits at various locations in work zones. Speed data is transformed into two groups—continuous for non-compliant and left-censored for compliant drivers—to model in a Tobit model framework. The modeling technique is illustrated using speed data from three long-term highway work zones in Queensland, Australia. Consistent and plausible model estimates across the three work zones support the appropriateness and validity of the technique. The results show that the probability and magnitude of speeding was higher for leaders of platoons with larger front gaps, during late afternoon and early morning, when traffic volumes were higher, and when higher proportions of surrounding vehicles were non-compliant. Light vehicles and their followers were also more likely to speed than others. Speeding was more common and greater in magnitude upstream than in the activity area, with higher compliance rates close to the end of the activity area and close to stop/slow traffic controllers. The modeling technique and results have great potential to assist in deployment of appropriate countermeasures by better identifying the traffic characteristics associated with speeding and the locations of lower compliance.

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Sparse optical flow algorithms, such as the Lucas-Kanade approach, provide more robustness to noise than dense optical flow algorithms and are the preferred approach in many scenarios. Sparse optical flow algorithms estimate the displacement for a selected number of pixels in the image. These pixels can be chosen randomly. However, pixels in regions with more variance between the neighbours will produce more reliable displacement estimates. The selected pixel locations should therefore be chosen wisely. In this study, the suitability of Harris corners, Shi-Tomasi's “Good features to track", SIFT and SURF interest point extractors, Canny edges, and random pixel selection for the purpose of frame-by-frame tracking using a pyramidical Lucas-Kanade algorithm is investigated. The evaluation considers the important factors of processing time, feature count, and feature trackability in indoor and outdoor scenarios using ground vehicles and unmanned aerial vehicles, and for the purpose of visual odometry estimation.

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Recent modelling of socio-economic costs by the Australian railway industry in 2010 has estimated the cost of level crossing accidents to exceed AU$116 million annually. To better understand the causal factors of these accidents, a video analytics application is being developed to automatically detect near-miss incidents using forward facing videos from trains. As near-miss events occur more frequently than collisions, by detecting these occurrences there will be more safety data available for analysis. The application that is being developed will improve the objectivity of near-miss reporting by providing quantitative data about the position of vehicles at level crossings through the automatic analysis of video footage. In this paper we present a novel method for detecting near-miss occurrences at railway level crossings from video data of trains. Our system detects and localizes vehicles at railway level crossings. It also detects the position of railways to calculate the distance of the detected vehicles to the railway centerline. The system logs the information about the position of the vehicles and railway centerline into a database for further analysis by the safety data recording and analysis system, to determine whether or not the event is a near-miss. We present preliminary results of our system on a dataset of videos taken from a train that passed through 14 railway level crossings. We demonstrate the robustness of our system by showing the results of our system on day and night videos.

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Monitoring the environment with acoustic sensors is an effective method for understanding changes in ecosystems. Through extensive monitoring, large-scale, ecologically relevant, datasets can be produced that can inform environmental policy. The collection of acoustic sensor data is a solved problem; the current challenge is the management and analysis of raw audio data to produce useful datasets for ecologists. This paper presents the applied research we use to analyze big acoustic datasets. Its core contribution is the presentation of practical large-scale acoustic data analysis methodologies. We describe details of the data workflows we use to provide both citizen scientists and researchers practical access to large volumes of ecoacoustic data. Finally, we propose a work in progress large-scale architecture for analysis driven by a hybrid cloud-and-local production-grade website.

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Protein molecular motors are natural nano-machines that convert the chemical energy from the hydrolysis of adenosine triphosphate into mechanical work. These efficient machines are central to many biological processes, including cellular motion, muscle contraction and cell division. The remarkable energetic efficiency of the protein molecular motors coupled with their nano-scale has prompted an increasing number of studies focusing on their integration in hybrid micro- and nanodevices, in particular using linear molecular motors. The translation of these tentative devices into technologically and economically feasible ones requires an engineering, design-orientated approach based on a structured formalism, preferably mathematical. This contribution reviews the present state of the art in the modelling of protein linear molecular motors, as relevant to the future design-orientated development of hybrid dynamic nanodevices. © 2009 The Royal Society of Chemistry.