Toll Roads in Australia: An Overview of Characteristics and Accuracy of Demand Forecasts

Abstract

A primary motivation of this paper is to draw together, in one source, information on the nature, extent and performance of Australia's evolving toll road network which is currently spread across many disparate published and unpublished sources. This paper provides key information (e.g. length, toll rates, year opened, operator(s) and payment alternatives) on all of the fully interoperable toll roads in Australia that are present in Sydney (e.g. the M2, M4, M5, etc.), Melbourne (CityLink and EastLink) and Brisbane (the Gateway Bridge, the Logan Motorway and the Gateway Extension). Where available, we compare and discuss actual traffic levels and forecasts, revealing the sizeable gap or ‘error’ in forecasts, especially during the first year of operation. Ordinary least squares regression and panel random effects regression models are developed to identify potential sources of explanation of differences in error forecasts between the Australian toll roads at various points post the opening date. A separate analysis of a sample of toll roads in the USA was also undertaken that supports the main findings from the Australian toll road network. Key influences on errors in forecasts are the capacity of a toll road, the elapsed time that the toll road has been in place, the specific period of time in which a tolled road is introduced into the network (which influences the complexity of route options including multiple tolled routes and hence toll saturation), the length of the tolled route, the presence of cash payment and the charging regime (i.e. fixed vs. distance‐based or variable user tolls).     

Making use of respondent reported processing information to understand attribute importance: a latent variable scaling approach

In recent years we have seen an explosion of research seeking to understand the role that rules and heuristics might play in improving the predictive capability of discrete choice models, as well as delivering willingness to pay estimates for specific attributes that may (and often do) differ significantly from estimates based on a model specification that assumes all attributes are relevant. This paper adds to that literature in one important way—it explicitly recognises the endogeneity issues raised by typical attribute non-attendance treatments and conditions attribute parameters on underlying unobserved attribute importance ratings. We develop a hybrid model system involving attribute processing and outcome choice models in which latent variables are introduced as explanatory variables in both parts of the model, explaining the answers to attribute processing questions and explaining heterogeneity in marginal sensitivities in the choice model. The resulting empirical model explains how lower latent attribute importance leads to a higher probability of indicating that an attribute was ignored or that it was ranked as less important, as well as increasing the probability of a reduced value for the associated marginal utility coefficient in the choice model. The model does so by treating the answers to information processing questions as dependent rather than explanatory variables, hence avoiding potential risk of endogeneity bias and measurement error.     

The Contribution of Benefit-in-Kind Taxation Policy in Britain to the ‘Peak Car’ Phenomenon

Car use per person has historically grown year-on-year in Great Britain since the 1950s, with minor exceptions during fuel crises and times of economic recession. The ‘Peak Car’ hypothesis proposes that this historical trend no longer applies. The British National Travel Survey provides evidence of such an aggregate levelling off in car mileage per person since the mid-1990s, but further analysis shows that this is the result of counter trends netting out: in particular, a reduction in per capita male driving mileage being offset by a corresponding increase in female car driving mileage. A major contributory factor to the decline in male car use has been a sharp reduction in average company car mileage per person. This paper investigates this aspect in more detail. Use of company cars fell sharply in Britain from the 1990s up to the 2008 recession. Over the same period, taxation policy towards company cars became more onerous, with increasing levels of taxation on the benefit-in-kind value of the ownership of a company car and on the provision of free fuel for private use. The paper sets out the changes in taxation policy affecting company cars in the UK, and looks at the associated reductions in company car ownership (including free fuel) and patterns of use. It goes on to look in more detail at which groups of the population have kept company cars and in which parts of the country they have been most used, and how these patterns have changed over time. A preliminary investigation is also made of possible substitution effects between company car and personal car driving and between company car use and rail travel. Clearly, the role of the company car is only one of many factors that are contributing to aggregate changes in levels of car use in Great Britain, alongside demographic changes and a wide range of policy initiatives. But, company car use cannot fall below zero, so the effect of declining year-on-year company car mileage suppressing overall car traffic levels cannot continue indefinitely.     

大型集装箱船和新巴拿马型船舶（NPX）

集装箱贸易显著的增长不仅表现在集装箱船队的总箱数已超过1100万箱，还表现在船的大小上。今天使用中的最大的集装箱船已超过1万箱。     

Air–sea gas transfer velocity estimates from the Jason-1 and TOPEX altimeters: Prospects for a long-term global time series

Estimation of global and regional air–sea fluxes of climatically important gases is a key goal of current climate research programs. Gas transfer velocities needed to compute these fluxes can be estimated by combining altimeter-derived mean square slope with an empirical relation between transfer velocity and mean square slope derived from field measurements of gas fluxes and small-scale wave spectra [Frew, N.M., Bock, E.J., Schimpf, U., Hara, T., Hauβecker, H., Edson, J.B., McGillis, W.R., Nelson, R.K., McKenna, S.P., Uz, B.M., Jähne, B., 2004. Air–sea gas transfer: Its dependence on wind stress, small-scale roughness and surface films, J. Geophys. Res., 109, C08S17, doi: 10.1029/2003JC002131.]. We previously reported initial results from a dual-frequency (Ku- and C-band) altimeter algorithm [Glover, D.M., Frew, N.M., McCue, S.J., Bock, E.J., 2002. A Multi-year Time Series of Global Gas Transfer Velocity from the TOPEX Dual Frequency, Normalized Radar Backscatter Algorithm, In: Gas Transfer at Water Surfaces, editors: Donelan, M., Drennan, W., Saltzman, E., and Wanninkhof, R., Geophysical Monograph 127, American Geophysical Union, Washington, DC, 325–331.] for estimating the air–sea gas transfer velocity (k) from the mean square slope of short wind waves (40–100 rad/m) and derived a 6-year time series of global transfer velocities based on TOPEX observations. Since the launch of the follow-on altimeter Jason-1 in December 2001 and commencement of the TOPEX/Jason-1 Tandem Mission, we have extended this time series to 12 years, with improvements to the model parameters used in our algorithm and using the latest corrected data releases. The prospect of deriving multi-year and interdecadal time series of gas transfer velocity from TOPEX, Jason-1 and follow-on altimeter missions depends on precise intercalibration of the normalized backscatter. During the Tandem Mission collinear phase, both satellites followed identical orbits with a mere 73-s time separation. The resulting collocated, near-coincident normalized radar backscatter (σ°) data from both altimeters present a unique opportunity to intercalibrate the two instruments, compare derived fields of transfer velocity and estimate the precision of the algorithm. Initial results suggest that the monthly gas transfer velocity fields generated from the two altimeters are very similar. Comparison of along-track Ku-band and C-band σ° during the collinear phase indicates that observed discrepancies are due primarily to small offsets between TOPEX and Jason-1 σ°. The Jason-1 k values have an apparent bias of + 4% relative to TOPEX, while the precision estimated from the two observation sets is 5–7% and scales with k. The resultant long-term, global, mean k is 16 cm/h.     

The combined effect of rain and wind on air–water gas exchange: A feasibility study

A series of experiments were conducted at University of Delaware's Air–Sea Interaction Laboratory to examine the combined effects of rain and wind on air–water gas exchange. During this study, ASIL WRX I, a combination of 3 rain rates and 4 wind speeds were used, for a total of 12 different environmental conditions. The SF₆ evasion method was used to determine the bulk gas transfer velocities, and airside profiles of wind and CO₂ were used to estimate flux–profiles of momentum and carbon dioxide. In addition to measurements of fluxes with and without rain in a wind–wave boundary layer, measurements of wave properties were also obtained. Rain is shown to alter the wind profile in the flume, and dampen surface waves. Also, SF₆ evasion indicates that with the present experimental setup, for most of the experimental conditions, rain and wind combine linearly to influence air–water gas exchange. Flux–profile relationships for marine atmospheric boundary layers, which were performed to scale up to field measurements, were explored by a comparison between SF₆-derived bulk fluxes and airside CO₂ profile measurements.     

船东眼中的标准

所谓标准,有一个定义就是:它们是在实践中用来衡量性能或确定和控制质量水平的各种技术规定或准则。标准可以是强制性的,也可以是自愿的。标准应当是清楚明白、均衡合理及协调一致的。标准的制订,被看作是弥合技能或品质差距的最有效途径。规定明确的各项标准,必须处理好所有利     

内圈蠕变引起的车轴轴承损伤进程的研究

车轴轴承内圈“蠕变”现象会导致内圈绕着车轴“旋转,”它是轴承磨损和发热的一个潜在的原因。人们仍不清楚内圈蠕变开始后车轴和轴承是如何迅速恶化的。文章用与实物等大的铁路车辆轴承在实验室进行了内圈蠕变仿真试验,调查了以内圈蠕变为起点的轴承损伤进程。试验结果揭示了轴承温度、振动以及车轴外径与内圈内径之间间隙的变化关系,并对内圈蠕变作出了预测。