Analytical benchmark solutions for steel frame structures subject to local buckling effects

Application of "advanced analysis" methods suitable for non-linear analysis and design of steel frame structures permits direct and accurate determination of ultimate system strengths, without resort to simplified elastic methods of analysis and semi-empirical specification equations. However, the application of advanced analysis methods has previously been restricted to steel frames comprising only compact sections that are not influenced by the effects of local buckling. A research project has been conducted with the aim of developing concentrated plasticity methods suitable for practical advanced analysis of steel frame structures comprising non-compact sections. This paper contains a comprehensive set of analytical benchmark solutions for steel frames comprising non-compact sections, which can be used to verify the accuracy of simplified concentrated plasticity methods of advanced analysis. The analytical benchmark solutions were obtained using a distributed plasticity shell finite element model that explicitly accounts for the effects of gradual cross-sectional yielding, longitudinal spread of plasticity, initial geometric imperfections, residual stresses, and local buckling. A brief description and verification of the shell finite element model is provided in this paper.

Randomised, double blind, placebo-controlled trial of Echinacea supplementation in air travellers

Objective. To identify whether a standardised Echinacea formulation is effective in the prevention of respiratory and other symptoms associated with long-haul flights. Methods. 175 adults participated in a randomised, double-blind placebo-controlled trial travelling back from Australia to America, Europe, or Africa for a period of 1–5 weeks on commercial flights via economy class. Participants took Echinacea (root extract, standardised to 4.4 mg alkylamides) or placebo tablets. Participants were surveyed before, immediately after travel, and at 4 weeks after travel regarding upper respiratory symptoms and travel-related quality of life. Results. Respiratory symptoms for both groups increased significantly during travel (

Tactile abstractions [Exhibition Catalogue Essay]

Among the many meanings of abstraction is the focus on images that are at a distance from their origins. This understanding of abstraction is central to Savanhdary Vongpoothorn’s layered, textured and sensuous canvas Crossing (2003). The references in this painting to Laotian textile design and creation endows it with the sense of a fabric-like nature, gives it the feel of cloth wrapped around bodies and of threads woven into complex symmetrical patterns. Here, the distance from origins is expressed as a separation from the material forms of Lao culture. At the same time the work is a visual reference to the stretching or bending of forms, the breaking up of shapes in the natural or constructed environment, all of which create an expressive effect through the warm rose grid and visual illusions of movement and travel. This visual play suggests the sense that migration or movement is a means through which cultural forms get recoded and translated. The making of Crossing like many of Savanhdary’s works involved manipulation of the canvas through pricking and poking, and then the application of layers and dots of paint. The overall effect is one of a synthesis of different cultural motifs and the addition of new dimensions to familiar forms. This highlights the centrality of the idea of 'reassemblage’ in abstraction, the processes of remaking of self, of the natural world and of cultural artefacts. Savanhdary constructs intricate laced knots of colour and texture in work which expresses the possibilities presented by travel, migration and the subsequent remixture that emerges upon crossing through different cultural worlds.

On parallel hybrid-electric propulsion system for unmanned aerial vehicles

This paper presents a review of existing and current developments and the analysis of Hybrid-Electric Propulsion Systems (HEPS) for small fixed-wing Unmanned Aerial Vehicles (UAVs). Efficient energy utilisation on an UAV is essential to its functioning, often to achieve the operational goals of range, endurance and other specific mission requirements. Due to the limitations of the space available and the mass budget on the UAV, it is often a delicate balance between the onboard energy available (i.e. fuel) and achieving the operational goals. One technology with potential in this area is with the use of HEPS. In this paper, information on the state-of-art technology in this field of research is provided. A description and simulation of a parallel HEPS for a small fixed-wing UAV by incorporating an Ideal Operating Line (IOL) control strategy is described. Simulation models of the components in a HEPS were designed in the MATLAB Simulink environment. An IOL analysis of an UAV piston engine was used to determine the most efficient points of operation for this engine. The results show that an UAV equipped with this HEPS configuration is capable of achieving a fuel saving of 6.5%, compared to the engine-only configuration.

Bayesian inference of traffic volumes based on Bluetooth data

The study of the relationship between macroscopic traffic parameters, such as flow, speed and travel time, is essential to the understanding of the behaviour of freeway and arterial roads. However, the temporal dynamics of these parameters are difficult to model, especially for arterial roads, where the process of traffic change is driven by a variety of variables. The introduction of the Bluetooth technology into the transportation area has proven exceptionally useful for monitoring vehicular traffic, as it allows reliable estimation of travel times and traffic demands. In this work, we propose an approach based on Bayesian networks for analyzing and predicting the complex dynamics of flow or volume, based on travel time observations from Bluetooth sensors. The spatio-temporal relationship between volume and travel time is captured through a first-order transition model, and a univariate Gaussian sensor model. The two models are trained and tested on travel time and volume data, from an arterial link, collected over a period of six days. To reduce the computational costs of the inference tasks, volume is converted into a discrete variable. The discretization process is carried out through a Self-Organizing Map. Preliminary results show that a simple Bayesian network can effectively estimate and predict the complex temporal dynamics of arterial volumes from the travel time data. Not only is the model well suited to produce posterior distributions over single past, current and future states; but it also allows computing the estimations of joint distributions, over sequences of states. Furthermore, the Bayesian network can achieve excellent prediction, even when the stream of travel time observation is partially incomplete.

Evaluation of two-view geometry methods with automatic ground-truth generation

A large number of methods have been published that aim to evaluate various components of multi-view geometry systems. Most of these have focused on the feature extraction, description and matching stages (the visual front end), since geometry computation can be evaluated through simulation. Many data sets are constrained to small scale scenes or planar scenes that are not challenging to new algorithms, or require special equipment. This paper presents a method for automatically generating geometry ground truth and challenging test cases from high spatio-temporal resolution video. The objective of the system is to enable data collection at any physical scale, in any location and in various parts of the electromagnetic spectrum. The data generation process consists of collecting high resolution video, computing accurate sparse 3D reconstruction, video frame culling and down sampling, and test case selection. The evaluation process consists of applying a test 2-view geometry method to every test case and comparing the results to the ground truth. This system facilitates the evaluation of the whole geometry computation process or any part thereof against data compatible with a realistic application. A collection of example data sets and evaluations is included to demonstrate the range of applications of the proposed system.

Gel dosimetry—it’s been the next big thing in radiotherapy for the past 25 years

Gel dosimetry and plastic chemical dosimeters such as PresageTM are capable of very accurately mapping dose distributions in three dimensions. Combined with their near tissue equivalence one would expect that after several decades of development they would be the dosimeter of choice for dosimetry, however they have not achieve widespread clinical use. This presentation will include a brief description and history of developments in gels and 3D plastics for dosimetry, the limitations and advantages, and their role in the future.

The experiences of teachers teaching children with Down syndrome in the early years of schooling

This innovative collective case study research documented teachers' experiences of teaching children with Down syndrome in the early years of schooling in Australia. Results indicated differences in teachers' conceptualisation of children with Down syndrome as learners and how these variations impacted the way the child was included within the class. Unique to this research was the utilisation of a mind-mapping technique of data collection which effectively captured the individual nature of teachers' experiences, making implicit knowledge explicit through description and interpretation of these experiences. Overall findings indicated that teachers were more likely to include children with Down syndrome into general education classrooms if they operated within a contemporary understanding of disability, had positive support from key stakeholders such as school principals and parents/caregivers, and had access to current information on Down syndrome from professional bodies.

A comparison of three models for mine water management

Water management is vital for mine sites both for production and sustainability related issues. Effective water management is a complex task since the role of water on mine sites is multifaceted. Computers models are tools that represent mine site water interaction and can be used by mine sites to inform or evaluate their water management strategies. There exist several types of models that can be used to represent mine site water interactions. This paper presents three such models: an operational model, an aggregated systems model and a generic systems model. For each model the paper provides a description and example followed by an analysis of its advantages and disadvantages. The paper hypotheses that since no model is optimal for all situations, each model should be applied in situations where it is most appropriate based upon the scale of water interactions being investigated, either unit (operation), inter-site (aggregated systems) or intra-site (generic systems).

Developments in mud filtration technology in the sugarcane industry

Dirt collected with sugarcane is processed and separated from the juice in the sugar factory by filtration equipment for return to the cane fields. New technologies over the past decade have enabled performance improvements to be obtained for this key unit operation. Filter mud product still contains a reasonable amount of sugar and the transportation of high moisture mud product has considerable cost. Australia’s traditional approach has been to use Rotary Vacuum Filters for processing and separating mud and other impurities from juice, but in recent years there has been interest in reducing sugar losses and transportation costs through utilisation of new technologies such as Horizontal Bed Filters, Vacuum Belt Press Filters, Membrane Press Filters and Centrifuges. Increasingly, these alternative equipment are being installed in new factories. This chapter describes the general principles of mud filtration theory and mud conditioning followed by a detailed description and review of the various filtration technologies and analysis of the relative merits associated with the equipment.

Social Justice Impacts of the Resources Boom

Until the 1970s mining leases were issued by state governments subject to conditions that companies build or substantially finance local community infrastructure, including housing, streets, transport, schools, hospitals and recreation facilities. Townships and communities went hand in hand with mining development. However, in the past thirty years mining companies have moved progressively to an expeditionary strategy for natural resources extraction - operating a continuous production cycle of 12 hour shifts - increasingly reliant on non-resident, fly-in, fly-out or drive-in, drive-out (FIFO/DIDO) workers who typically work block rosters, reside in work camps adjacent to existing communities and travel large distances from their homes. This paper presents the key findings of our survey into the social impacts of this kind of mining development in Qld. Based on the results we argue that the social license to develop new mining projects is strong for projects requiring a 25% or less non-resident workforce, diminishes significantly thereafter and is very weak for projects planning to recruit a non-resident workforce in excess of 75%. This finding is significant because there are at least 67 new mining projects undergoing social impact assessment in Queensland, and many it appears are planning to hire significant proportions of non-resident workers. The paper considers the policy implications of this growing social justice issue concluding there is a clear need for national leadership in formulating a national policy framework for guiding socially responsible and sustainable mining development into the next millennium.

Understanding Uncertainties in Non-Linear Population Trajectories: A Bayesian Semi-Parametric Hierarchical Approach to Large-Scale Surveys of Coral Cover

Recently, attempts to improve decision making in species management have focussed on uncertainties associated with modelling temporal fluctuations in populations. Reducing model uncertainty is challenging; while larger samples improve estimation of species trajectories and reduce statistical errors, they typically amplify variability in observed trajectories. In particular, traditional modelling approaches aimed at estimating population trajectories usually do not account well for nonlinearities and uncertainties associated with multi-scale observations characteristic of large spatio-temporal surveys. We present a Bayesian semi-parametric hierarchical model for simultaneously quantifying uncertainties associated with model structure and parameters, and scale-specific variability over time. We estimate uncertainty across a four-tiered spatial hierarchy of coral cover from the Great Barrier Reef. Coral variability is well described; however, our results show that, in the absence of additional model specifications, conclusions regarding coral trajectories become highly uncertain when considering multiple reefs, suggesting that management should focus more at the scale of individual reefs. The approach presented facilitates the description and estimation of population trajectories and associated uncertainties when variability cannot be attributed to specific causes and origins. We argue that our model can unlock value contained in large-scale datasets, provide guidance for understanding sources of uncertainty, and support better informed decision making

"Nursing is no place for men" ― A thematic analysis of male nursing students experiences of undergraduate nursing education

Background: Surprisingly, opinion about whether men are suitable within the profession continues to be a divided issue. Men enter the profession for a multitude of reasons, yet barriers whether emotional, verbal or sexual are still present. Aim: The aim of this study was to examine the experience of men “training” to be registered nurses within a regional New Zealand context. Design: A Narrative Analysis approach was used. Participants: Five New Zealand men currently undertaking their bachelor of nursing degree at a regional tertiary institute were interviewed as to their experiences of what it meant to be a man in “training”. Method: A thematic analysis was undertaken and guided by an understanding of the way personal narratives informs the human sciences especially within the context of nursing praxis. Four key themes were identified. Results: Four key themes were identified: A career with flexibility and promise; perceived gender inequality in providing care; developing professional boundaries with female colleagues and being unique has its advantages. Conclusion: The men in this study were attracted to the profession by career stability and advancement; the opportunities for travel also figured highly. At times they felt excluded and marginalised because of their minority status within their group and the feminine nature of the curriculum. The men attempted to dispel the myth around male nurse sexual stereotypes. Some of the students behaved in a manner to exert their heterosexualness. The students in this study sensed their vulnerability in choosing nursing as a career. However, all the participants saw nursing as viable and portable career in terms of advancement and travel.

Effects of transit quality of service characteristics on daily bus ridership

This study explores how explicit transit quality of services (TQoS) measures including service frequency, service span, and travel time ratio, along with implicit environmental predictors such as topographic grade factor influence bus ridership using a case study city of Brisbane, Australia. The primary hypothesis tested was that bus ridership is higher within suburbs with high transit quality of service than suburbs that have limited service quality. Using Multiple Linear Regression (MLR) this study identifies a strong positive relationship between route intensity (bus-km/h-km2) and bus ridership, indicating that increasing both service frequency and spatial route density correspond to higher bus ridership. Additionally, travel time ratio (in-vehicle transit travel time to in-vehicle auto travel time) is also found to have significant negative association with ridership within a suburb, reflecting a decline in transit use with increased travel time ratio. Conversely, topographic grade and service span are not found to exert any significant impact on bus ridership in a suburb. Our study findings enhance the fundamental understanding of traveller behaviour which is informative to urban transportation policy, planning and provision.

Effects of transit quality of service characteristics on daily bus ridership

This study investigates whether an Australian city’s suburbs having high transit Quality of Service (QoS) are associated with higher transit ridership than those having low transit QoS •We explore how QoS measures including service frequency, service span, service coverage, and travel time ratio, along with implicit environmental predictors such as topographic grade factor influence bus ridership •We applied Multiple Linear Regression (MLR) to examine the relationship between QoS and ridership •Its outcomes enhance our understanding of transit user behavior, which is informative to urban transportation policy, planning, and provision