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Despite the longevity, scale and importance of northern Australia’s beef industry, recent disruptions to external markets have demonstrated a degree of vulnerability to shocks in the supply chain. Matching the industry’s long-evident resilience to climatic variability with resilience to changes in markets and supply chains requires careful planning. One component of this is how investments in infrastructure will need to be planned to facilitate adaptive responses to market changes. This paper provides an outline of a modelling framework that links strategic and operational dynamic models of logistics along the supply chain from the property to the abattoir or port. A novelty of the methodology is that it takes into account the high granularity of individual livestock transport vehicle movements and the ability to scale up to an almost complete view of logistics costs across the entire beef industry of northern Australia. The paper illustrates how the methodology could be used to examine the effects of changes in logistics infrastructure on efficiency and costs using examples from the states of Northern Territory, Western Australia and Queensland.

Burning of fine fuels is a crucial activity in Australia as part of reducing the severity of bushfires. Seasonal planning of such planned burning is a very complex task owing to the large number of practical considerations and uncertainty of burn conditions, as well as personnel and equipment resource constraints. Practical considerations include the small number of suitable burn days for different types of burns, as well as different fuel hazard and burn types. This requires careful management of very high resource requirements during the available days. We developed a tool that will use all of the above variables to estimate the resource requirements for different levels of planned burning program. We provide a mathematical programming approach to help plan burning crews and equipment resource requirements in each district by month to minimise likely personnel requirements, under seasonal uncertainty. A key feature is that it accommodates maximum daily resource demands given uncertainty in available burn days and overlap between geographical districts. We implemented the model on a real-world problem of public land across Victoria, and solved it to optimality using GAMS/Cplex 9.

Before railway track maintenance crews can undertake any work, the allocation of activities to available time intervals in the train schedule as well as to crews must be undertaken. This paper puts forward a model aimed at determining the best allocation of maintenance activities and crews so as to mininise the disruption to and from scheduled trains and to reduce completion time. The model is subject to constraints such as available budget; maintenance activity precedence; track availability; and minimum travel time between track links. Solution to the model is found using the tabu search heuristic for which the neighbourhood is defined by swapping the order of jobs, maintenance crews, or both. Application to a 300 km track corridor with a four day planning horizon is discussed along with the impacts of modifying the number of maintenance crews. The optimal schedule achieved an 8% reduction in expected interference delay with the train schedule and a 7% reduction in average completion times, relative to the solution which was constructed manually.

Perfusion of Phe-Met-Arg-Phe-NH(2) (FMRFamide), an endogenous neuropeptide, through the gill of Aplysia significantly potentiates the amplitude of the gill withdrawal reflex evoked by tactile stimulation of the siphon with or without the central nervous system present. The potentiating effect of FMRFamide is reversible with washout. FMRFamide perfusion of the gill also prevented the gill withdrawal reflex from undergoing habituation when the tactile stimulus was presented repeatedly. Rather than habituate, the gill withdrawal reflex increased in amplitude. FMRFamide continued to prevent habituation in the absence of the parietal-visceral ganglion. We hypothesize that FMRFamide plays a role in the mediation of behavioural state primarily by affecting activity in the peripheral nervous system in the gill.

The BIOCONAID System represents the development of a new technique for enhancing the fidelity of flight simulators during high acceleration maneuvers. This technique forces the simulator pilot into active participation and energy expenditure similar to the aircraft pilot undergoing actual accelerations. The system consists of an electromyographic (EMG) subsystem and the software implementation of four physiological models: Cardiovascular Model; G-Suit Model; Straining Model, and Visual Field Model. The EMG subsystem is required for signal processing of muscular straining signals used in the Straining Model. The EMG subsystem and all software except the Visual Field Model have been carefully checked-out to yield results consistent with experimental data and known physiology. Consequently, the BIOCONAID System has the potential of providing a very realistic simulation of visual dimming with straining during high accelerations. It is recommended that the system be implemented and evaluated in an Air Force simulator with experienced pilots. (Author)