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Mixed integer programming and parallel-machine job shop scheduling are used to solve the sugarcane rail transport scheduling problem. Constructive heuristics and metaheuristics were developed to produce a more efficient scheduling system and so reduce operating costs. The solutions were tested on small and large size problems. High-quality solutions and improved CPU time are the result of developing new hybrid techniques which consist of different ways of integrating simulated annealing and Tabu search techniques.

Rutting has the potential to lead to hazardous driving conditions and is a concern for the asphalt community. Asphalt mixture behaviour is significantly governed by the properties of the used bitumen. Because of the increasing demand for better performance, current studies have tended to focus on developing rheological binder tests that can be used to accurately predict asphalt performance especially for modified binders. In addition, there is an essential requirement to consider the interactions between components in an asphalt mixture. This paper presents a new procedure to characterise the creep and recovery properties of pure bitumen and mastics using a modified multiple stress-strain creep recovery test. To understand the authentic mechanism of rutting resistance, two new factors comprising ltime factorr and lnormalised recoveryr are introduced. The results indicate that creep and recovery are functions of filler concentration, stress level, strain level and temperature.

A cylindrical dc coaxial glow discharge system with inner grid cathode was designed for ion confinement, and success- fully operated with low discharge current. The plasma is formed inside the cylindrical grid cathode. The discharge cur- rentvoltage characteristic curves and Paschen curve are obtained at different gas pressures. Langmuir probes are used to determine the electron temperature and the plasma density. The electron energy distribution functions indicated that, two groups of electrons, appear in radial interval from r = 12 mm up to r = 5 mm. One group of electrons with most probable energy around 1 eV appeared from r = 5 mm up to r = 0. The electron temperature Te is increased with increasing the current and also with moving from the center toward the grid cathode. Poisson’s equation is used to calculate the plasma density at different radial positions. The plasma density measured by the single probe is around 1015 m-3. A comparison is obtained between calculated plasma density and that measured by Langmuir probes. Experimental and calculated results have the same profile.

The sugarcane transport system is very complex and uses a daily schedule, consisting of a set of locomotives runs, to satisfy the requirements of the mill and harvesters. The total cost of sugarcane transport operations is very high; over 35% of the total cost of sugarcane production in Australia is incurred in cane transport. Producing efficient schedules for sugarcane transport can reduce the cost and limit the negative effects that this system can have on the raw sugar production system. In this paper, the sugarcane rail operations are formulated as a blocking job shop scheduling problem. A mixed integer programming approach is used to formulate the shop job scheduling problem. Mixed integer programming and constraint programming search techniques are integrated for solving the problem. A case study is solved to test the approach.

This paper characterises binder and mastic behaviour under shear creep and creeprecovery tests. Although several researchers have investigated the creep and recovery behaviour of pure and polymer modified bitumen, there is a primary need to investigate the behaviour of mastic in such a way to better correlate with the behaviour of asphalt mixtures. The steady state condition under creep testing and recovery behaviour under creep recovery testing are characterised through testing in the dynamic shear rheometer (DSR) under a wide range of stresses and temperatures. 40/60 pen pure bitumen as well as binder-filler mastics containing limestone blended at three different concentrations [35%, 50%, and 65% by mass of mastic] were utilised for this study. Creep testing results indicated that pure bitumen and mastics behave linearly at low stress levels and nonlinearly at high stress levels. In addition, the stiffening effect of filler is characterised through a new Stiffing Factor. Stiffening Factor was determined for each bitumen-mastic combination obtained under similar testing conditions based on a steady-state curve fitting technique. Results analysis of creeprecovery tests showed that the recovery property of the bitumen is affected by both stress limit and filler concentration but insignificantly influenced by temperature. Moreover, the recovery property of bituminous material reduces with increasing filler content.

The distributed generation (DG) today attracts a large interest due to an even increasing demand of energy and the growth of awareness about the impact of conventional energy sources on the environment. Photovoltaic (PV) and wind power are two of the most promising renewable energy technologies. Fuel cell (FC) systems also show enormous potential in future DG applications, due to a fast technology development, high efficiency, environment friendliness and modularity. Hybrid systems encompassing wind, photovoltaic and FC generators are today revised as a viable solution to overcome the inner unreliability of renewable energy sources. The modelling and control of a hybrid wind/PV/FC DG system is addressed in this dissertation. Dynamic models for the main system components, namely: wind and PV energy generators, fuel cell, electrolyser, power electronic interfaces, battery, hydrogen storage tank, gas compressor, are developed and verified by experimental tests and simulation studies. Five different architectures of stand-alone hybrid power systems are considered, exploiting connections through DC and AC buses. Each configuration is managed through a specific control methodology. Based on suitable dynamic models, the five proposed stand-alone hybrid energy system configurations have been simulated using the MATLAB/Simulink/SimPowSysTM software environment. A comparison among those configurations has been performed on the basis of purposely developed performance indexes. According to obtained results the high voltage DC bus (HVDC) configuration reaches the best score among the five configurations. A Fuzzy logic based management of a stand-alone hybrid generator based on high voltage DC bus configuration has been developed to dynamically optimize the power flows among the different energy sources. The performances of the proposed strategy are evaluated by simulation in different operating conditions. The results confirm the effectiveness of the proposed strategy. A further goal of the thesis has been the development of a probabilistic approach to size step-up transformers for grid-connected wind farms. This approach is mainly based on the evaluation of the Loss of Produced Power Probability index (LPPP); the costs of the wind farm equipments are also taken into consideration.

Red light running at signalised intersections is a growing road safety issue worldwide, leading to the rapid development of advanced intelligent transportation technologies and countermeasures. However, existing studies have yet to summarise and present the effect of these technology based innovations in improving safety. This paper represents a comprehensive review of red light running behaviour prediction methodologies and technology-based countermeasures. Specifically, the major focus of this study is to provide a comprehensive review on two streams of literature targeting red light running and stop and go behaviour at signalised intersection (1) studies focusing on modelling and predicting the red light running and stop and go related driver behaviour and (2) studies focusing on the effectiveness of different technology based countermeasures which combat such unsafe behaviour. The study provides a systematic guide to assist researchers and stakeholders in understanding how to best identify red light running and stop and go associated driving behaviour and subsequently implement countermeasures to combat such risky behaviour and improve the associated safety., Published in IEEE ACCESS

Asphalt mixture, the most common road construction material, comprises bitumen, filler, fine and coarse aggregates, and air voids. Traditionally and for simplification, the mixture is treated as a continuous and homogenous material confined in the domain of linear behaviour. The demand for more durable roads, particularly with the progressive growth in traffic volumes and loads, has raised the requirement for improved design methods. Wisely, before the complex adoption of the nonlinear behaviour, understanding the nature of the internal stress-strain relationships at different scales and determining their linearity limits is essentially required taking into consideration the time and temperature dependency. \ud \ud So far, most experimental programs have been concerned with testing either asphalt mixture or bitumen in isolation. This thesis is intended to establish a systematic experimental investigation from binder to the asphalt mixture scale in terms of permanent deformation behaviour. Preliminary conclusions of the components contributions, their interactions, and the effect on the total macroscopic response are drawn from the experimental observations. \ud \ud Investigation of the fillers influence on the viscoelastic property of the mastic (filler +bitumen) binder in the dynamic shear rheometer (DSR), results exhibited that binder behave nonlinearly at high shear stress levels and the linearity range reduces with increasing filler content and/or raising the temperature. Although filler inclusion increased the deformation resistance (stiffness) of the binder, its recoverability decreased. Consequently, a new binder rutting evaluation test was designed to distinguish between the two rutting resistance mechanisms; stiffness and recovery. Results from the new test indicated that the linearity of the modified binders begins after an initial inherent nonlinearity stage and before a secondary nonlinearity stage triggered by the applied state of stresses in the DSR. \ud \ud A new designed mortar type was developed from the mastic and originated from a standard asphalt mixture. The focus of this part in the research emphasised on measuring the stiffening effect of fine aggregates utilising a constitutive stress-strain relationship and determining the influence on the viscoelastic behaviour. Results indicated that the stiffening effect varies depending on the stress condition (uniaxial, triaxial, or shear), temperature, fine aggregate gradation, and binder with filler content. The stress linearity limit was also found to vary at different degrees with the previous parameters. \ud \ud Uniaxial compression constant stress and strain rate tests were conducted on asphalt mixtures of different aggregate gradations at 30 and 500C. X-ray CT was incorporated to characterise the coarse aggregates and air voids through advanced image analysis techniques. The test was shown to be insensitive to the asphalt mixture type in terms of air voids uniformity. Mixtures of coarse aggregates produced larger size and smaller number of air voids, opposite to the fine aggregate ones. Comparing the stiffening effect between fine and coarse aggregates, it was revealed that the air void content is a key factor. Finally, the radial strain as measured along the height followed the pattern of air void distribution in the specimen and exhibited both tensile and compressive forms.