Hydraulic Performances of Minimum Energy Loss Culverts in Australia

Culverts are among the most common hydraulic structures. Modern designs do not differ from ancient structures and are often characterised by significant afflux at design flows. A significant advance was the development of the Minimum Energy Loss (MEL) culverts in the late 1950s. The design technique allows a drastic reduction in upstream flooding associated with lower costs. The development and operational performances of this type of structure is presented. The successful operation of MEL culverts for more than 40 years is documented with first-hand records during and after floods. The experiences demonstrate the design soundness while highlighting the importance of the hydraulic expertise of the design engineers

Hydraulic engineering in the 21st century: Where to?

For centuries, hydraulic engineers were at the forefront of science. The last forty years marked a change of perception in our society with a focus on environmental sustainability and management, particularly in developed countries. Herein, the writer illustrates his strong belief that the future of hydraulic engineering lies upon a combination of innovative engineering, research excellence and higher education of quality. This drive continues a long tradition established by eminent scholars like Arthur Thomas IPPEN, John Fisher KENNEDY and Hunter ROUSE

Quasielastic 12C(e,e'p) Reaction at High Momentum Transfer

We measured the 12C(e,e'p) cross section as a function of missing energy in parallel kinematics for (q,w) = (970 MeV/c, 330 MeV) and (990 MeV/c, 475 MeV). At w=475 MeV, at the maximum of the quasielastic peak, there is a large continuum (E_m > 50 MeV) cross section extending out to the deepest missing energy measured, amounting to almost 50% of the measured cross section. The ratio of data to DWIA calculation is 0.4 for both the p- and s-shells. At w=330 MeV, well below the maximum of the quasielastic peak, the continuum cross section is much smaller and the ratio of data to DWIA calculation is 0.85 for the p-shell and 1.0 for the s-shell. We infer that one or more mechanisms that increase with $\omega$ transform some of the single-nucleon-knockout into multinucleon knockout, decreasing the valence knockout cross section and increasing the continuum cross section.Comment: 14 pages, 7 figures, Revtex (multicol, prc and aps styles), to appear in Phys Rev

Modelling the Environmental Benefits of ITS using Power-Based Vehicle Emissions ModelsLondon, England

This paper demonstrates the feasibility of using power-based vehicle emissions models to evaluate the environmental benefits of ITS. An incident management strategy that can reduce the duration of an incident blocking all lanes from 30 to 15 minutes was found to have the potential to provide 22 percent reduction in fuel consumption rate and 20 percent reduction in CO2. The provision of real-time travel information was also tested. The results suggest that the implementation of a VMS route guidance strategy has potential to reduce fuel consumption by 9.2 percent, CO emissions by 1.4 percent and CO2 emissions by 8.7 percent

Simulation of ITS impacts on network performance

The work reported in this paper is part of an on-going research project aimed at modelling the impacts of ITS applications using microscopic traffic simulation models. In particular, this paper presents the results of incident-induced impacts on the performance of an arterial network. A microscopic simulation model was developed for the Western commuting corridor in Brisbane, and was used to assess the impacts of simulated incidents on average travel time, speed, fuel consumption and environmental emissions. The model was found to replicate (under-predict) traffic conditions within 6% of observed intersection volumes throughout the corridor, and matched observed travel times on a major route within acceptable levels. As expected, the impact of incidents was found to vary with severity (number of blocked lanes) and duration. The results also suggest that reducing a single lane incident duration from 30 minutes to 15 minutes provides a 12% increase in average travel speed, and 31% decrease in time spent in queue. These results demonstrate the feasibility and benefits of the simulation approach in assessing the impacts of ITS applications. Further work is being carried out to evaluate the impacts of other ITS applications, including evaluation of driver compliance with travel information systems

Assessment of incident-induced impacts on the performance of an arterial network

This paper presents a simulation approach to the assessment of incident-induced impacts on a commuting corridor between the western suburbs and the central business district (CBD) area in Brisbane. A microscopic simulation model was calibrated for the study area and used to assess the impacts of simulated incidents on average travel times, speeds, fuel consumption and environmental emissions. The model was found to replicate (under-predict) traffic conditions within 15% of observed volumes on the corridor. The impact of incidents was found to vary with severity (number of blocked lanes) and duration. Incidents blocking both lanes and lasting for 60 minutes resulted in 38% increase in network travel time; 15% increase in fuel consumption and 73% increase in hydrocarbon emissions. Section-specific impacts were more pronounced, resulting in an increase of more than 140% in travel times for an incident blocking the fast lane and lasting for 15 minutes on Coronation Drive. These impacts are expected to be greater on networks operating at or near capacity. The results reported in this paper demonstrate the feasibility of the approach and provide directions to extend the model's capabilities in evaluating the effectiveness of incident management plans in the study area

Simulation of arterial incident detection using neural networks

This paper discusses a modular neural network arterial incident detection model that was developed and evaluated using simulated data. A microscopic traffic simulation model of a commuting corridor in Brisbane was used to generate a total of 36 incidents at different times of the day, with varying severity and duration. The neural network model uses speed, flow and occupancy data, provided in 20-second cycles from both the upstream and downstream stations, in addition to section travel times. The model was trained on 23 incidents and its performance evaluated on the remaining 13 incidents. The initial results reported in this paper demonstrate the feasibility of using modular neural networks for arterial incident detection and provide directions for developing fast and reliable automated arterial incident detection models

Quasielastic C-12(e,e ' p) reaction at high momentum transfer

We measured the C-12(e,e'p) cross section as a function of missing energy in parallel kinematics for (q,omega)=(970 MeV/c, 330 MeV) and (990 MeV/c, 475 MeV). At omega=475 MeV, at the maximum of the quasielastic peak, there is a large continuum (E-m>50 MeV) cross section extending out to the deepest missing energy measured, amounting to almost 50% of the measured cross section. The ratio of data to distorted-wave impulse approximation (DWIA) calculation is 0.4 for both p and s shells. At omega = 330 MeV, well below the maximum of the quasielastic peak,the continuum cross section is much smaller and the ratio of data to DWIA calculation is 0.85 for the p shell and 1.0 for the s shell. We infer that one or more mechanisms that increase with omega transform some of the single-nucleon knockouts into a multinucleon knockout, decreasing the valence knockout cross section and increasing the continuum cross section. [S0556-2813(99)00701-3]