366 resultados para Fluid transport


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This paper investigated the influence of nano-silica (NS) on the mechanical and transport properties of lightweight concrete (LWC). The resistance of LWC to water and chloride ions penetration was enhanced despite strength marginally increased. Water penetration depth, moisture sorptivity, chloride migration and diffusion coefficient was reduced by 23% and 49%, 23% and 10%, 5% and 0%, 22% and 12% compared to the two reference LWC mixes (pure cement and 60% slag blended cement), respectively with 1% NS. Such improvements were attributed to more compact microstructures because the micropore system was refined and the interface between aggregates and paste was enhanced.

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The Queensland Department of Transport and Main Roads (TMR) required an evaluation framework for the Queensland Alcohol Ignition Interlock Program (AIIP). The objective of this project was to develop a framework to evaluate the AIIP in terms of its effect on road safety outcomes.

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Unlicensed driving remains a serious problem for road safety, despite ongoing improvements in traffic law enforcement practices and technology. While it does not play a direct causative role in road crashes, unlicensed driving undermines the integrity of the driver licensing system and is associated with a range of high-risk behaviours. This report examines official road crash data from Queensland for the years 2003-08 to compare the crash involvement patterns of unlicensed drivers with those of licensed drivers and explore the scope and nature of unlicensed driving. This study replicates and extends upon two previous studies examining the involvement of unlicensed drivers in crashes in Queensland (Watson, 2004a; 2004b; Watson & Steinhardt, 2006).

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A state-wide observational study was undertaken by the Centre for Accident Research and Road Safety – Queensland (CARRS-Q) in order to investigate the prevalence of unregistered vehicles on Queensland roads. This study was conducted on behalf of the Queensland department of Transport and Main Roads (TMR). This study builds upon research commissioned by Queensland Transport and conducted in 2000, 2003 and 2005. Vehicles were observed throughout Queensland from April 13th, 2010 to May 8th, 2010 in a mix of small rural towns, regional centres and metropolitan locations. The locations sampled for this study were restricted to destinations (e.g. shopping centres, hospitals, airports and park-and-ride facilities) rather than residential areas, and a variety of different destinations were sampled. Sampling vehicles in these types of locations provides a higher probability that the vehicles captured in the survey are being driven on a regular basis (Younglove, et al. 2004).

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Vehicle registration represents an important component of the management of the road transport system in Queensland, with most vehicles required to be registered before they can be driven or parked on a public road (Department of Transport and Main Roads, 2010b). In addition to the collection of taxes for road construction and maintenance, the current registration system also: • Sets the safety standards required for vehicles to be allowed on public roads; • Allows driver behaviour to be managed by identifying vehicles, and the responsible owners of vehicles, for enforcement purposes; and • Facilitates the collection of insurance premiums for the Queensland Compulsory Third Party (CTP) insurance scheme.

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Unlicensed driving is a serious problem in many countries, despite ongoing improvements in traffic law enforcement practices and technology. The term ‘unlicensed driver' is generally used to refer to people who operate a motor vehicle or motorcycle without a valid driver's licence, including those who: • have let their licence expire; • have been disqualified or suspended from driving; • hold an inappropriate class of licence for the vehicle they drive; • drive outside the restrictions of a special licence; • don’t currently hold a licence; or • have never held a licence.

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This report documents a second, revised roadside licence check survey undertaken by the Queensland Police Service (QPS) in conjunction with roadside random breath testing (RBT) traffic operations. The methodology utilised was devised by the Centre for Accident Research and Road Safety – Queensland (CARRS-Q), Transport and Main Roads (TMR) and QPS, after consideration of a number of options.

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Unlicensed driving is a serious problem in many countries, despite ongoing improvements in traffic law enforcement practices and technology. Unlike alcohol impairment and speeding, unlicensed driving does not play a direct causative role in road crashes. However it represents a major problem for road safety in two respects. Firstly, it undermines the effectiveness of driver licensing systems by preventing the allocation of demerit points and reducing the impact of licence loss (Watson, 2004b). Secondly, there is a growing body of evidence linking unlicensed driving to a cluster of high-risk behaviours including drink driving, speeding, failure to wear seat belts and motorcycle use (Griffin & DeLaZerda, 2000; Harrison, 1997; Watson, 1997, 2004b). Consistent with this, utilising the quasi-induced exposure method, Watson (2004a) estimated that in Queensland, unlicensed drivers were almost three times more likely to be involved in a reported crash than licensed drivers.

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Unlicensed driving remains a serious problem for road safety, despite ongoing improvements in traffic law enforcement practices and technology. This report examines de-identified traffic infringement and sanction histories for drivers in Queensland who had lost their licence between 1st January 2003 and 31st December 2008. A total of 546,117 Queensland drivers were identified. Key areas discussed include the prevalence of unlicensed driving and the extent to which particular offences were detected amongst drivers with a licence sanction or disqualified licence.

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There is a lack of definitive evidence available relating to the extent and nature of unlicensed driving. Analysis of the crash involvement of unlicensed drivers provides an opportunity to better understand the behaviours of this group. This paper reviews the available literature relating to crash involvement patterns of unlicensed drivers. Key areas discussed include the prevalence of unlicensed driving as indicated by studies of crashes involving this group and associations between unlicensed driving and higher levels of risk-taking on the road. This paper also notes differences found in the characteristics and on-road behaviour of unlicensed drivers and the degree to which these factors, in particular alcohol and drug misuse, may influence crash involvement patterns. Drawing on Australian and international studies, this paper consolidates the available research evidence and identifies gaps in current knowledge relating to crash involvement patterns of unlicensed drivers.

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Unlicensed driving remains a serious problem for road safety, despite ongoing improvements in traffic law enforcement practices and technology. While it does not play a direct causative role in road crashes, unlicensed driving undermines the integrity of the driver licensing system and is associated with a range of high-risk behaviours. The Queensland Transport and Main Roads (TMR) commissioned a program of research with separate components relating to different aspects of unlicensed driving. Drawing on Australian and international studies, the Unlicensed and Unregistered Vehicle (UUV) project explores the nature of unlicensed driving in Queensland, consolidates the available research evidence and identifies gaps in current knowledge relating to the driving behaviours of unlicensed drivers.

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There is a current lack of understanding regarding the use of unregistered vehicles on public roads and road-related areas, and the links between the driving of unregistered vehicles and a range of dangerous driving behaviours. This report documents the findings of data analysis conducted to investigate the links between unlicensed driving and the driving of unregistered vehicles, and is an important initial undertaking into understanding these behaviours. This report examines de-identified data from two sources: crash data; and offence data. The data was extracted from the Queensland Department of Transport and Main Roads (TMR) databases and covered the period from 2003 to 2008.

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Improving safety at railway level crossings is an important issue for the Australian transport system. Governments, the rail industry and road organisations have tried a variety of countermeasures for many years to improve railway level crossing safety. New types of Intelligent Transport System (ITS) interventions are now emerging due to the availability and the affordability of technology. These interventions target both actively and passively protected railway level crossings and attempt to address drivers’ errors at railway crossings, which are mainly a failure to detect the crossing or the train and misjudgement of the train approach speed and distance. This study aims to assess the effectiveness of three emerging ITS that the rail industry considers implementing in Australia: a visual in-vehicle ITS, an audio in-vehicle ITS, as well as an on-road flashing beacons intervention. The evaluation was conducted on an advanced driving simulator with 20 participants per trialled technology, each participant driving once without any technology and once with one of the ITS interventions. Every participant drove through a range of active and passive crossings with and without trains approaching. Their speed approach of the crossing, head movements and stopping compliance were measured. Results showed that driver behaviour was changed with the three ITS interventions at passive crossings, while limited effects were found at active crossings, even with reduced visibility. The on-road intervention trialled was unsuccessful in improving driver behaviour; the audio and visual ITS improved driver behaviour when a train was approaching. A trend toward worsening driver behaviour with the visual ITS was observed when no trains were approaching. This trend was not observed for the audio ITS intervention, which appears to be the ITS intervention with the highest potential for improving safety at passive crossings.

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Pilot and industrial scale dilute acid pretreatment data can be difficult to obtain due to the significant infrastructure investment required. Consequently, models of dilute acid pretreatment by necessity use laboratory scale data to determine kinetic parameters and make predictions about optimal pretreatment conditions at larger scales. In order for these recommendations to be meaningful, the ability of laboratory scale models to predict pilot and industrial scale yields must be investigated. A mathematical model of the dilute acid pretreatment of sugarcane bagasse has previously been developed by the authors. This model was able to successfully reproduce the experimental yields of xylose and short chain xylooligomers obtained at the laboratory scale. In this paper, the ability of the model to reproduce pilot scale yield and composition data is examined. It was found that in general the model over predicted the pilot scale reactor yields by a significant margin. Models that appear very promising at the laboratory scale may have limitations when predicting yields on a pilot or industrial scale. It is difficult to comment whether there are any consistent trends in optimal operating conditions between reactor scale and laboratory scale hydrolysis due to the limited reactor datasets available. Further investigation is needed to determine whether the model has some efficacy when the kinetic parameters are re-evaluated by parameter fitting to reactor scale data, however, this requires the compilation of larger datasets. Alternatively, laboratory scale mathematical models may have enhanced utility for predicting larger scale reactor performance if bulk mass transport and fluid flow considerations are incorporated into the fibre scale equations. This work reinforces the need for appropriate attention to be paid to pilot scale experimental development when moving from laboratory to pilot and industrial scales for new technologies.