Queensland Department of Transport and Main Roads

Stated choice (SC) experiments are often used in transportation studies for estimating and forecasting behaviour of travellers, road authorities, etc. This kind of experiment relies on underlying experimental designs. Whilst orthogonal designs are mainstream for practitioners, many researchers now realize that so‐called efficient designs are able to produce more efficient data in the sense that more reliable parameter estimates can be achieved with an equal or lower sample size. This paper describes several processes for generating SC experiments and is intended to give an overview of the current state‐of‐the‐art. Different methods are described.

Transit service reliability is an important determinant of service quality, which has been mainly studied from the perspective of passengers waiting at stops. Day-to-day variability of travel time also deteriorates service reliability, but is not a well-researched area in the literature partly due to the lack of comprehensive data sets on bus travel times. While this problem is now being addressed through the uptake of global positioning system (GPS)-based tracking systems, methodologies to analyze these data sets are limited. This paper addresses this issue by investigating day-to-day variability in public transport travel time using a GPS data set for a bus route in Melbourne, Australia. It explores the nature and shape of travel time distributions for different departure time windows at different times of the day. Factors causing travel time variability of public transport are also explored using a linear regression analysis. The results show that in narrower departure time windows, travel time distributions are best characterized by normal distributions. For wider departure time windows, peak-hour travel times follow normal distributions, while off-peak travel times follow lognormal distributions. The factors contributing to the variability of travel times are found to be land use, route length, number of traffic signals, number of bus stops, and departure delay relative to the scheduled departure time. Travel time variability is higher in the AM peak and lower in the off-peak. The impact of rainfall on travel time variability is only found significant in the AM peak. While the paper presents new methods for analyzing GPS-based data, there is much scope for expanding knowledge through wider applications to new data sets and using a wider range of explanatory variables.

Latent class models offer an alternative perspective to the popular mixed logit form, replacing the continuous distribution with a discrete distribution in which preference heterogeneity is captured by membership of distinct classes of utility description. Within each class, preference homogeneity is usually assumed, although interactions with observed contextual effects are permissible. A natural extension of the fixed parameter latent class model is a random parameter latent class model which allows for another layer of preference heterogeneity within each class. This article sets out the random parameter latent class model and illustrates its applications using a stated choice data set on alternative freight distribution attribute packages pivoted around a recent trip in Australia.

Accessibility indexing is important in evaluating existing land use patterns and transportation services, predicting travel demands and allocating transportation investments.A GIS-based land use and public transport accessibility indexing model has been developed for measuring and mapping levels of accessibility to basic community services by walking and/or public transport, within local government areas.The model aims to assist the planning and decision making process to deliver integrated land use and transportation outcomes.It is an originbased accessibility model that determines levels of accessibility by utilising GIS analysis techniques to measures accessibility based on both actual walking distances and public transport travel time.The model has been applied to two pilot studies in the Gold Coast City to assess its practicality and effectiveness.This paper outlines the methodology of the model and the findings related to these pilot studies.The paper also demonstrates benefits and application of the model to other urbanised local government areas.

We compared the movement patterns of cricketers in different playing positions across three formats of cricket (Twenty20, One Day, multi-day matches). Cricket Australia Centre of Excellence cricketers (n = 42) from five positions (batting, fast bowling, spin bowling, wicketkeeping, and fielding) had their movement patterns (walk, jog, run, stride, and sprint) quantified by global positioning system (GPS) technology over two seasons. Marked differences in movement patterns were evident between positions and game formats, with fast bowlers undertaking the greatest workload of any position in cricket. Fast bowlers sprinted twice as often, covered over three times the distance sprinting, with much smaller work-to-recovery ratios than other positions. Fast bowlers during multi-day matches covered 22.6 +/- 4.0 km (mean +/- s) total distance in a day (1.4 +/- 0.9 km in sprinting). In comparison, wicketkeepers rarely sprinted, despite still covering a daily total distance of 16.6 +/- 2.1 km. Overall, One Day and Twenty20 cricket required approximately 50 to 100% more sprinting per hour than multi-day matches. However, multi-day cricket's longer duration resulted in 16-130% more sprinting per day. In summary, the shorter formats (Twenty20 and One Day) are more intensive per unit of time, but multi-day cricket has a greater overall physical load.

During the last two decades the public sector has come under increasing pressure to improve performance and demonstrate greater transparency and accountability. This pressure has resulted in public sector organisations facing shifts in ways of operating. Various corporate change strategies have been adopted by different public sector agencies, many of these cloning managerial practices from the private sector. These changes in public sector organisations have enormous significance for regional economic and social development. While there is a growing body of knowledge dealing with the management of corporate change there are still significant gaps in understanding the process. While there is much written on public versus private corporate change, there is little distinguishing between change in different types of public sector organisations. This paper analyses change management processes and seeks to determine whether a hybrid model of “new public management” delivers more favourable outcomes than a model focused on cost reduction and private sector prejudice for the bottom line.

This paper presents results regarding the potential of lignosulfonate (LS) to control the swelling of expansive soil. One-dimensional swell tests were performed on untreated and LS-treated remoulded samples of Australian expansive soil from the state of Queensland. The test results indicated that LS has significant influence on the swelling behaviour of this expansive soil. The results were compared with those of identical cement-treated soil samples, and it was found that LS could be a economical and environmentally friendly alternative to traditional alkaline additives. In addition, the behaviour of LS-treated specimens during repeated freezing and thawing cycles was measured. The results indicated significant improvement in the percentage mass loss in LS-treated specimens compared with cement-treated specimens. The microstructural analysis of the untreated and the LS-treated samples showed soil surface area reduction in the treated specimens, which in turn reduced the affinity of the specimens towards moisture uptake, resulting in a reduction in the swell potential of the otherwise expansive soil. The use of LS as a novel non-traditional stabiliser for expansive soil appears to be a viable solution in view of the sustainable use of waste by-products and green construction.

OBJECTIVE: To assess the factors, including helmet use, that contribute to head linear and angular acceleration in bicycle crash simulation tests. METHOD: A series of laboratory tests was undertaken using an oblique impact rig. The impact rig included a drop assembly with a Hybrid III head and neck. The head struck a horizontally moving striker plate. Head linear and angular acceleration and striker plate force were measured. The Head Injury Criterion was derived. The following test parameters were varied: drop height to a maximum of 1.5 m, horizontal speed to a maximum of 25 km/h, helmet/no helmet, impact orientation/location, and restraint adjustment. Additional radial impacts were conducted on the same helmet models for comparison purposes. Descriptive statistics were derived and multiple regression was applied to examine the role of each parameter. RESULTS: Helmet use was the most significant factor in reducing the magnitude of all outcome variables. Linear acceleration and the Head Injury Criterion were influenced by the drop height, whereas angular acceleration tended to be influenced by the horizontal speed and impact orientation/location. The restraint adjustment influenced the outcome variables, with lower coefficients of variation observed with the tight restraint. CONCLUSIONS: The study reinforces the benefits of wearing a bicycle helmet in a crash. The study also demonstrates that helmets do not increase angular head acceleration. The study assists in establishing the need for an agreed-upon international oblique helmet test as well as the boundary conditions for oblique helmet testing.

BACKGROUND: A severe form of iron overload with the clinicopathological features of haemochromatosis inherited in an autosomal dominant manner has been described in the Solomon Islands. The genetic basis of the disorder has not been identified. The disorder has similarities to type 4 haemochromatosis, which is caused by mutations in ferroportin1. AIMS: The aims of this study were to identify the genetic basis of iron overload in a patient from the Solomon Islands. PATIENT AND METHODS: Genomic DNA was isolated from peripheral blood leucocytes of a Solomon Islands man with severe iron overload. The entire coding region and splice sites of the ferroportin1 gene was sequenced. RESULTS AND CONCLUSIONS: A novel missense mutation (431A>C; N144T) was identified in exon 5 of the ferroportin1 gene. A novel restriction endonuclease based assay which identifies both the N144T and N144H mutations was developed which will simplify the diagnosis and screening of patients for iron overload in the Solomon Islands and other populations. This is the first identified mutation associated with haemochromatosis in the Solomon Islands population.

Over the last 15 years we have seen a small but growing interest in Prospect Theory (PT) as an alternative behavioural paradigm within which to represent traveller behaviour. Some elements of PT such as gains and losses have become so popular in travel choice studies that authors increasingly indicate that they are applying PT. In its strictest interpretation, PT has a number of essential elements that must be included if the link with PT can be claimed. This paper reviews recent transportation studies which report an association with PT as a way of gaining a greater appreciation of what is and what is not an application of PT. We set the scene by providing an overview of PT using studies in the fields of psychology and behavioural economics, where PT was originally established and further developed, and then identify travel behaviour studies which satisfy the PT (Original or Cumulative PT) conditions. A number of specific issues are identified to highlight the connection to PT, including empirically estimated prospect theoretic parameters and referencing. Some behavioural limitations of the reviewed transport PT studies are also presented, including the absence of willingness to pay estimates and consideration of unobserved between‐individual heterogeneity.

The emergence of new technologies allows better monitoring of traffic conditions and understanding of urban network dynamics. Bluetooth technology is becoming widespread, as it represents a cost-effective means for capturing road traffic in both arterials and motorways. Although the extraction of travel time from Bluetooth data is fairly straightforward, data reliability and processing is still challenging with the issues of penetration rate, mode discrimination, and detection quality. This paper presents a methodological contribution to the use of Bluetooth data for the spatiotemporal analysis of a large urban network (Brisbane, Australia). It introduces the concept of the Bluetooth origin-destination (B-OD) matrix, which is built from a network of 79 Bluetooth detectors located within the Brisbane urban area. The B-OD matrix describes the dynamics of a subpopulation of vehicles, between pairs of detectors. The results show that the characteristics of urban networks can be effectively represented through B-OD matrices. A comparison with loop detector data enables an assessment of the results' significance. Then, the spatiotemporal structure of the network is analyzed with two different clustering analyses, namely, latent Dirichlet allocation (LDA) and $K$-means. While LDA is used to detect a temporal pattern, the $K$-means algorithm highlights Bluetooth fundamental diagram (BFD) classes. The results show that Bluetooth data has the potential to be a reliable data source for traffic monitoring. By highlighting hidden structures of a large area, the algorithm outputs allow us to provide the road operators with a fine spatiotemporal analysis of their network, in terms of traffic conditions.

This study presents a revised approach to conceptualising and analysing data from the traffic speed deflectometer (TSD) which enables full deflection bowl predictions. The approach was successfully applied to TSD surface velocity measurements collected at seven test sites as part of recent Australian trials. More than 1500 deflection bowls produced from the TSD data were validated against approximately 600 40- and 50-kN falling weight deflectometer (FWD) deflection bowl profiles. Overall, the results showed a clear correlation between the shape and magnitude of deflection bowls predicted by both methods. Estimates of maximum deflection (d 0) and structural curvature index (SCI300) from both methods were also compared, showing a strong correlation. The results suggest that the TSD device has significant potential to be used to collect measurements of pavement deflection bowls at highway speeds which are comparable with FWD deflection bowl measurements.

BACKGROUND: Given increasing investment in new cycling infrastructure, it is important to understand its impacts. The Sydney Transport and Health Study evaluates a new 2.4 km bi-directional separated bicycle path in inner-Sydney. This paper describes the users of the new bicycle path, and examines its short-term impacts upon cycling behaviour and perceptions of the local environment. METHODS: Data were collected from two bike counts at two intersections on the new bicycle path in the intervention area in 2013 and 2014. On-line surveys collected individual participant data in the intervention area and a similar comparison area before the bicycle path was built (2013), and 12 months later (four months after completion) (n = 512). The data included self-reported cycling behaviour, use of the new bicycle path and perceptions of changes in the local environment. RESULTS: Bike counts at two sites on the new bicycle path reported an increase of 23% and 97% respectively at 12 months. However, among the participants in the cohort, there was no change in the self-reported weekly frequency of cycling. One in six (approximately 15%) participants reported using the new bicycle path, with most users (76%) living in the intervention area. Bicycle path users were most likely to be frequent riders (at least weekly) [adjusted odds ratio (AOR) = 7.50, 95 % CI 3.93-14.31], be a high intensity recreational rider (AOR = 4.38, 95 % CI 1.53-12.54) or a low intensity transport rider (AOR = 2.42, 95 % CI 1.17-5.04) and live closer to the bicycle path (AOR = 1.24, 1.13-1.37). Perceptions that the neighbourhood was more pleasant, that there were more people walking and cycling were significantly higher in the intervention area at 12 months (both P values <0.05). CONCLUSIONS: Existing cycling behaviour and proximity to the bicycle path were associated with the use of the new bicycle path. Increased use of the new bicycle path as reported by the participants in the intervention area and increased cycling recorded by the bike counts may be due to existing cyclists changing routes to use the new path, and more cyclists from outside the study area using the new path, as study participants did not increase their frequency of cycling. Increases in cycling frequency in the intervention neighbourhood may require a longer lead time, additional promotional activities and further maturation of the Sydney bicycle path network. KEY MESSAGE: Understanding how new cycling infrastructure impacts communities can influence the promotion of such infrastructure.

Issue addressed A key strategy to increase active travel is the construction of bicycle infrastructure. Tools to evaluate this strategy are limited. This study assessed the usefulness of a smartphone GPS tracking system for evaluating the impact of this strategy on cycling behaviour. Methods Cycling usage data were collected from Queenslanders who used a GPS tracking app on their smartphone from 2013-2014. 'Heat' and volume maps of the data were reviewed, and GPS bicycle counts were compared with surveillance data and bicycle counts from automatic traffic-monitoring devices. Results Heat maps broadly indicated that changes in cycling occurred near infrastructure improvements. Volume maps provided changes in counts of cyclists due to these improvements although errors were noted in geographic information system (GIS) geo-coding of some GPS data. Large variations were evident in the number of cyclists using the app in different locations. These variations limited the usefulness of GPS data for assessing differences in cycling across locations. Conclusion Smartphone GPS data are useful in evaluating the impact of improved bicycle infrastructure in one location. Using GPS data to evaluate differential changes in cycling across multiple locations is problematic when there is insufficient traffic-monitoring devices available to triangulate GPS data with bicycle traffic count data. So what? The use of smartphone GPS data with other data sources is recommended for assessing how infrastructure improvements influence cycling behaviour.

Heterogeneous traffic flow contains the mixed operation of the different vehicle classes such as cars, trucks and buses. Previous study has indicated that the overall stability of the heterogeneous traffic flow is governed by a weighted mean of stability parameters corresponding to each vehicle class and is not affected by the order in which a vehicle class is put into the system, for example either car or truck. However, it has been recently reported that the effect of mixed composition on traffic flow dynamics is also determined by the car-following vehicle type, that is either car following a car or car following a truck. This paper aims at investigating analytically how different car-following combinations (i.e. the following type) influence the overall stability of heterogeneous traffic flow dynamics. More specifically, we will consider the four types of car-following behaviour such as car–car, car–truck, truck–car, and truck–truck. The effect of such car-following types on the overall linear stability condition of the heterogeneous traffic flow will be studied using a generalised multi-class car-following model in which the optimal speed function is not only dependent on the the space headway between two consecutive vehicles as in previous study of Mason and Woods [1997. “Car-following Model of Multispecies Systems of Road Traffic.” Physical Review E: 2203–2214] but also on the and the relative speed between those two consecutive vehicles.

A billion persons live in slums worldwide, and 2 million households live in informal housing in South Africa. The stated goal of the South African government is to overcome this housing backlog by 2014; but doubling the budget will achieve this by only 2030. Current policy is to deliver a choice of housing alternatives; but in practice ‘a house on a fully serviced property with freehold title’ is seen as the only alternative. This paper describes a model that estimates the value that residents of an informal settlement place on aspects such as level of municipal engineering services, location and type of upgrade, and the size of the dwelling. The model was applied to three issues in the current debate on informal settlement upgrading in South Africa; namely: whether to upgrade by relocating all residents to a ‘greenfield’ site or upgrading ‘in situ’? Whether to upgrade incrementally across many settlements or upgrade fully one settlement at a time? Whether to offer residents more than one upgrade alternative? The stated choice approach provides a method to develop and test many housing alternatives as part of involving the community in the upgrading of an informal settlement.

The results of a 10 year study of bicycle fatalities and an eight year study of serious non-fatalities are reported for urban Brisbane (population 1,000,000). There were 845 serious non-fatal bicycle accidents and 46 fatalities during the study. Boys were involved in 86% of accidents. Boys have an accident rate of 134.21 per 100,000 population at risk and a fatality rate of 5.06 per 100,000 at risk. Serious bicycle accidents have increased by 50% in this decade; but considering fatal cases alone, no secular trend was evident over the 10 year period of the study. This suggests that an increase in the overall rate of bicycle accidents has been in part compensated by less serious injuries. In 70% of fatalities children had head injuries, and 87% of fatalities followed a collision between a cyclist and a motor vehicle or a train. Bicycle accidents on the roads most commonly occur to boys aged between 12 and 14 years on a straight road at "mid-block" between 3 and 5 pm in clear weather conditions and in daylight. It is concluded that injuries and fatalities after bicycle accidents can be reduced by protecting children's heads, separating child cyclists from other road traffic, or educating and training both cyclists and other road users in safe behaviour. The compulsory use of helmets and the restriction of access to the roads by child cyclists to reduce injuries are, however, still controversial in many areas.

The common approach to estimate bus dwell time at a Bus Rapid Transit (BRT) station platform is to apply the traditional dwell-time methodology derived for suburban bus stops. Current dwell-time models are sensitive toward bus type and fare collection policy along with the number of boarding and alighting passengers. However, they fall short in accounting for the effects of passengers walking on a relatively longer BRT station platform. Analysis presented in this paper shows that the average walking time of a passenger at a BRT platform is 10 times more than that of a bus stop. The requirement of walking to the bus entry door at the BRT station platform may lead to the bus experiencing a higher dwell time. This paper presents a theory for a BRT network that explains the loss of station capacity during peak period operation. It also highlights shortcomings of present available bus dwell-time models suggested for the analysis of BRT operation.

The macroscopic fundamental diagram (MFD) relates space mean density and flow. The existence with dynamic features was confirmed in a congested urban network in downtown Yokohama, Japan, with a real data set. Because the MFD represents areawide network traffic performance, studies have reported on perimeter control strategies and areawide traffic state estimated with the MFD concept. However, few reports of real-world examples from signalized arterial networks are available. Data are fused from multiple sources (Bluetooth devices, loop detectors, and signal phase timing). A framework is presented for the development of the MFD for Brisbane, Queensland, Australia. Existence of the MFD in the Brisbane arterial network is confirmed. MFDs (from the entire network and several subregions) are evaluated to determine the spatial partitioning to represent network performance. The findings confirm the usefulness of appropriate network partitioning for traffic monitoring and incident detection. Future research directions are addressed.

The harsh Australian environment makes the use of steel reinforcement in concrete structures problematic on account of corrosion. The probability of corrosion damage will significantly increase in the years to come and will become a major problem not only in coastal regions but also in inland parts of Australia due to increasing carbon dioxide concentration, temperature, and relative humidity as a consequence of climate change. In the last two decades, glass fiber-reinforced polymer (GFRP) composite bars have become an alternative to steel reinforcement for reinforcing concrete structures exposed to harsh environments. The reinforcing material is noncorrodible, nonmagnetic, lightweight, and has high tensile strength, thus making it a viable reinforcing material for concrete structures. This paper provides the state-of-the-practice in the research, development, and application of GFRP bars, with the aim of properly informing the engineering community about this alternative, noncorrodible reinforcing technology. The paper also presents a strategy toward the development of fiber-reinforced polymer bar material specifications with the aim to ensure quality use and application of the GFRP material in a wide range of applications in Australia in the years to come. Moreover, the best practices and data presented in this paper will be very useful in the development of unified international standards and specifications for GFRP bars.