Use of available storage to improve scheduling in an automobile assembly plant

The Final Assembly Plant at General Motors-Holden's Automotive Ltd converts painted body shells into drive-away vehicles. It encounters difficulties when processing certain sequences of vehicles with high work contents, so GMHAL wishes to schedule its input to reduce or eliminate such undesirable sequences. GMHAL has a set of empirical rules for delineating undesirability. The Painted Body Storage (PBS), which precedes Final Assembly, has 4 lanes that can be used to partially reschedule a vehicle sequence. Information on vehicle work content is available prior to arrival at the PBS, and GMHAL wants advice on using this data and the PBS to achieve a more satisfactory input to Final Assembly. The Study Group devised three approaches. 1. Use the rules to show which short sequences are desirable and devise input and output strategies for the PBS to achieve these consistently. Choice between the strategies requires further investigation. 2. Model Final Assembly to produce an optimality criterion for vehicle sequences and use combinatorial optimization methods to optimise it over possible PBS outputs. A characterization of these outputs was derived. 3. Suggest that the initial production be suitably scheduled, which may substantially reduce the difficulties at the PBS stage

Modelling and analysis of wheel replacement and restoration

"Given this system with its inherent constraints, what is the relationship between the stock of spare wheelsets on hand and the probability of not having a wheelset of the correct size on hand to effect a wheel change?

The role of subjective factors in local authorities' action on climate change in South West England

This study examines the question of whether subjective attitudes to climate change play a significant part in the determination of local authorities’ policy and actions on climate change mitigation; whether the personal views of council members and officers about climate change, their beliefs, fears and attitudes affect the outcomes in terms of policy and action, or whether organizational culture, norms and collectively policed limits to discourse have this effect; or whether, on the contrary, the influence of central government policy is so overwhelming that action and policy is determined almost wholly by external and objective influences. The research fills a gap in the literature in studying both subjective attitudes and socio-cultural factors together with external and material factors in order to assess the importance of the former. Interviews with officers and members of local authorities in the South West of England and other data identify that considerable reductions in councils’ own greenhouse emissions have been achieved, not wholly due to cutbacks and other contextual factors, but policy for more widespread carbon reduction in their geographical areas was more limited. Central government finance and policy were key determinants of action in all the local authorities studied, but significant differences between authorities are linked to differences in the prevalence of climate change dismissal. Psycho-social methods are used to achieve a more subtle and coherent view of individual attitudes to climate change, to identify relevant aspects of corporate culture, and to tease out how objective influences such as financial incentives and political pressures interact with these attitudes. The study finds that climate dismissal and denial present obstacles to carbon reduction initiatives and reduce the number which emerge; it also identifies the way organizational culture, including the growing dominance of financial and economic discourse, can constrain possibilities and proposals. Based on the interview data, I argue that financial incentives not only encourage but enable discussion of carbon reduction measures, and that severe budgetary constraints undermine a sense of agency as well as curtailing long term ambition in carbon reduction. Perceived lack of agency, at times deployed as a ‘tool of innocence’, also emerges as a key contributor to climate change dismissal, as well as more specific political and personal attitudes. Implications for policy at local and national level are derived from the research findings

Drying and shrinkage of computer simulated paper

We describe the modelling and computation of paper shrinkage during drying, using a finite difference method and simulated paper structure. Radial contraction of drying fibres leads to axial compression of crossing, bonded fibres. This microcompression process makes a major contribution to the shrinkage of the paper. The influence of fibre orientation is computed, and shown to be very significant, in accordance with observations. The method relies on the possibility of maintaining fixed anisotropic stiffness constants as the network rotates

Distribution of the apple maggot Rhagoletis pomonella (Diptera: Tephritidae) in Oregon

Data from a four-year (1981-1984) distributional study suggest that, in Oregon, the apple maggot <i>Rhagoletis pomonella</i> (Walsh) is established in the interior valleys (especially the Willamette Valley) along the Columbia River Gorge and at isolated locations along the Oregon coast. An analysis of the general distribution pattern and some earlier records suggests that the apple maggot may have been in Oregon for nearly four decades

Investigation of the fundamental constants stability based on the reactor Oklo burn-up analysis

The burn-up for SC56-1472 sample of the natural Oklo reactor zone 3 was calculated using the modern Monte Carlo codes. We reconstructed the neutron spectrum in the core by means of the isotope ratios: $^{147}$Sm/$^{148}$Sm and $^{176}$Lu/$^{175}$Lu. These ratios unambiguously determine the spectrum index and core temperature. The effective neutron absorption cross section of $^{149}$Sm calculated using this spectrum was compared with experimental one. The disagreement between these two values allows to limit a possible shift of the low laying resonance of $^{149}$Sm even more . Then, these limits were converted to the limits for the change of the fine structure constant $\alpha$. We found that for the rate of $\alpha$ change the inequality $|\delta \dot{\alpha}/\alpha| \le 5\cdot 10^{-18}$ is fulfilled, which is of the next higher order than our previous limit.Comment: 16 pages, 7 figure

On the Wilf-Stanley limit of 4231-avoiding permutations and a conjecture of Arratia

We construct a sequence of finite automata that accept subclasses of the class of 4231-avoiding permutations. We thereby show that the Wilf-Stanley limit for the class of 4231-avoiding permutations is bounded below by 9.35. This bound shows that this class has the largest such limit among all classes of permutations avoiding a single permutation of length 4 and refutes the conjecture that the Wilf-Stanley limit of a class of permutations avoiding a single permutation of length k cannot exceed (k-1)^2.Comment: Submitted to Advances in Applied Mathematic

Detection of flying-foxes using automated audio recorders

Flying-foxes are little understood in Australia largely due to their extreme mobility. This mobility is particularly evident in the two species (spectacled and little red) found across the north of Australia, where huge numbers of animals will suddenly converge on a region and then leave a few weeks later. To improve management of these species we need to understand the movement and ecology of the animals and this is not straightforward as the camps are often remote and inaccessible. In this project we aimed to test the viability of using automated acoustic recorders for determining the presence of spectacled flying-foxes at camp locations. A Song Meter SM4 recorder was used to record flying-foxes in a number camps around South East QLD/Northern Rivers (black and grey-headed flying-foxes) and Cairns (spectacled flying-fox). A total of 35 hour of flying-foxes calls were recorded over a period of 8 weeks from August to October 2017. The recordings were processed using a Binary Winnow classifier and Hidden Markov Model in Kaleidoscope Software (Wildlife Acoustics). Tagged one-minute recordings were used to train the Hidden Markov Model in Kaleidoscope which was subsequently used in classifying the remaining recordings. Using this approach, we were able to quickly and easily detect the presence of flying-foxes in the acoustic recordings. In this way, ecologists can easily implement projects for long-term monitoring of flying-fox populations using remotely deployed acoustic recorders. It may also assist management agencies for urban planning in northern Australia. For future work, we will be investigate advanced machine learning algorithms coupled with flying-fox behavioural call patterns to attempt to distinguish the species of flying-fox from acoustic recordings

Longitudinal Change in Common Impairments in Children with Cerebral Palsy from age 1.5 to 11 years

Purpose: This project aimed to determine if change occurs over time for impairments of balance, range of motion (ROM), endurance, and strength of children with cerebral palsy (CP), by Gross Motor Function Classification System (GMFCS) levels. Methods: Measurements were completed in 77 children at two sessions (T1, T2) on average 5.8 years apart. Mean ages were 2.9 years (SD .9) and 8.7 years (SD 1.1) at T1 and T2, respectively. Results: Significant differences were noted from T1 to T2 for some children (GMFCS levels I, II, and III/IV: balance increased, GMFCS levels I and II: strength increased, and GMFCS levels III/IV and V: ROM decreased). Endurance scores were not different. Endurance scores did not change. Conclusions: Longitudinal changes in most impairments occurred in children with CP. Monitoring and targeted interventions should support each child’s development