Comparative study of failure mechanisms in steel and concrete members strengthened with CFRP composites

Over the last decade advanced composite materials, like carbon fibre reinforced polymer (CFRP), have increasingly been used in civil engineering infrastructure. The benefits of advanced composites are rapidly becoming evident. This paper focuses on the comparative performance of steel and concrete members retrofitted by carbon fibre reinforced polymers. The objective of this work is a systematic assessment and evaluation of the performance of CFRP for both the concrete and steel members available in the technical literature. Existing empirical and analytical models were studied. Comparison is made with respect to failure mode, bond characteristics, fatigue behaviour, durability, corrosion, load carrying capacity and force transfer. It is concluded that empirical expressions for the concrete-CFRP composite are not readily suited for direct use in the steel-CFRP composite. This paper identifies some of the major issues that need further investigation.

Ignition delay of bio-fuels in a common-rail compression ignition engine

The utility of a novel technique for determining the ignition delay in a compression ignition engine has been shown. This method utilises statistical modelling in the Bayesian paradigm to accurately resolve the start of combustion from a band-pass in-cylinder pressure signal. Applied to neat diesel and six biofuels, including four fractionations of palm oil of varying carbon chain length and degree of unsaturation, the relationships between ignition delay, cetane number and oxygen content have been explored. It is noted that the expected negative relationship between ignition delay and cetane number held, as did the positive relationship between ignition delay and oxygen content. The degree of unsaturation was also identified as a potential factor influencing the ignition delay.

The bioeconomics of nutritional poverty and child labour

This paper provides a bio-economic foundation of fertility and child labor. Drawing on the clinical and physiological literature, the model highlights the interaction between work efforts of adults and children, their subsistence consumption, and fertility. The subsistence consumption requirements are endogenous to physical efforts. Parents engaged in physically demanding occupations (e.g. non-mechanized agriculture) are likely to suffer from energy deficiency, leading to reduced future work-capacity. Consumption smoothing occurs through bearing a large number of children who provide income support as adults. Although net cost of an additional child is positive, the cost is balanced by the additional income accruing though child employment. In contrast, parents in low-physical effort occupations are less likely to su¤er from nutritional deficiency, and thus tend to have lower fertility and child labor.

HMM relative entropy rate concepts for vision-based aircraft manoeuvre detection

Machine vision is emerging as a viable sensing approach for mid-air collision avoidance (particularly for small to medium aircraft such as unmanned aerial vehicles). In this paper, using relative entropy rate concepts, we propose and investigate a new change detection approach that uses hidden Markov model filters to sequentially detect aircraft manoeuvres from morphologically processed image sequences. Experiments using simulated and airborne image sequences illustrate the performance of our proposed algorithm in comparison to other sequential change detection approaches applied to this application.

Consistent HMM parameter estimation using Kerridge inaccuracy rates

In this paper, we propose a novel online hidden Markov model (HMM) parameter estimator based on Kerridge inaccuracy rate (KIR) concepts. Under mild identifiability conditions, we prove that our online KIR-based estimator is strongly consistent. In simulation studies, we illustrate the convergence behaviour of our proposed online KIR-based estimator and provide a counter-example illustrating the local convergence properties of the well known recursive maximum likelihood estimator (arguably the best existing solution).

My Kitchen Rules pair are all the rage on social media – for now

The launch of the current series of My Kitchen Rules has undoubtedly been successful, both in terms of television ratings and in capturing a social media audience, clearly winning the battle for the Twitter audience on premiere night, and maintaining a lead over both The Block and The Biggest Loser since then. But it is the controversy surrounding Perth contestants Kelly Ramsay and Chloe James that has dominated media coverage today, detailing the abuse to which they have been subjected on social media.

The baby boomers and beyond report : physical activity levels of older Western Australians 2006

Participation in sufficient levels of physical activity provides significant health benefits, particularly in older adults. The monitoring of physical activity levels in the Western Australian population is therefore necessary for developing and implementing strategies and programs for increasing participation. The Premier’s Physical Activity Taskforce (PATF) conducted a survey in 2006 to measure physical activity levels among Western Australian adults to follow-up the 1999 and 2002 state physical activity surveys. There is now widespread agreement that many health problems of older life – including the onset of frailty and disability – can be postponed or delayed by adopting health-enhancing habits such as physical activity. Adults over 65 years are the most rapidly growing age group and will continue to rise as more persons turn 65. If older adults could be encouraged to be more active as they age, frailty and disability associated with falls would be reduced, and function and physical and mental health in older people would be improved thereby reducing the burden of disease and injury. Given that physical inactivity is one of the most important and modifiable risk factors contributing to ill health, particularly for people as they age, the overall aim of this study was to examine patterns of physical activity in those aged 45 years and over – referred to hereafter as baby boomers+ – in more detail.

Access to commercial destinations within the neighbourhood and walking among Australian older adults

BACKGROUND: Physical activity, particularly walking, is greatly beneficial to health; yet a sizeable proportion of older adults are insufficiently active. The importance of built environment attributes for walking is known, but few studies of older adults have examined neighbourhood destinations and none have investigated access to specific, objectively-measured commercial destinations and walking. METHODS: We undertook a secondary analysis of data from the Western Australian state government's health surveillance survey for those aged 65--84 years and living in the Perth metropolitan region from 2003--2009 (n = 2,918). Individual-level road network service areas were generated at 400 m and 800 m distances, and the presence or absence of six commercial destination types within the neighbourhood service areas identified (food retail, general retail, medical care services, financial services, general services, and social infrastructure). Adjusted logistic regression models examined access to and mix of commercial destination types within neighbourhoods for associations with self-reported walking behaviour. RESULTS: On average, the sample was aged 72.9 years (SD = 5.4), and was predominantly female (55.9%) and married (62.0%). Overall, 66.2% reported some weekly walking and 30.8% reported sufficient walking (>=150 min/week). Older adults with access to general services within 400 m (OR = 1.33, 95% CI = 1.07-1.66) and 800 m (OR = 1.20, 95% CI = 1.02-1.42), and social infrastructure within 800 m (OR = 1.19, 95% CI = 1.01-1.40) were more likely to engage in some weekly walking. Access to medical care services within 400 m (OR = 0.77, 95% CI = 0.63-0.93) and 800 m (OR = 0.83, 95% CI = 0.70-0.99) reduced the odds of sufficient walking. Access to food retail, general retail, financial services, and the mix of commercial destination types within the neighbourhood were all unrelated to walking. CONCLUSIONS: The types of neighbourhood commercial destinations that encourage older adults to walk appear to differ slightly from those reported for adult samples. Destinations that facilitate more social interaction, for example eating at a restaurant or church involvement, or provide opportunities for some incidental social contact, for example visiting the pharmacy or hairdresser, were the strongest predictors for walking among seniors in this study. This underscores the importance of planning neighbourhoods with proximate access to social infrastructure, and highlights the need to create residential environments that support activity across the life course.

Selling new neighborhoods as good for walking : issues for measuring self-selection

Background: Self-selection-whether individuals inclined to walk more seek to live in walkable environments-must be accounted for when studying built environment influences on walking. The way neighborhoods are marketed to future residents has the potential to sway residential location choice, and may consequently affect measures of self-selection related to location preferences. We assessed how walking opportunities are promoted to potential buyers, by examining walkability attributes in marketing materials for housing developments. Methods: A content analysis of marketing materials for 32 new housing developments in Perth, Australia was undertaken, to assess how walking was promoted in the text and pictures. Housing developments designed to be pedestrian-friendly (LDs) were compared with conventional developments (CDs). Results: Compared with CDs, LD marketing materials had significantly more references to 'public transport,' small home sites,' walkable parks/open space,' ease of cycling,' safe environment,' and 'boardwalks.' Other walkability attributes approached significance. Conclusion: Findings suggest the way neighborhoods are marketed may contribute to self-reported reasons for choosing particular neighborhoods, especially when attributes are not present at the time of purchase. The marketing of housing developments may be an important factor to consider when measuring self-selection, and its influence on the built environment and walking relationship.

The impact of the built environment on health across the life course : design of a cross-sectional data linkage study

Introduction: The built environment is increasingly recognised as being associated with health outcomes. Relationships between the built environment and health differ among age groups, especially between children and adults, but also between younger, mid-age and older adults. Yet few address differences across life stage groups within a single population study. Moreover, existing research mostly focuses on physical activity behaviours, with few studying objective clinical and mental health outcomes. The Life Course Built Environment and Health (LCBEH) project explores the impact of the built environment on self-reported and objectively measured health outcomes in a random sample of people across the life course. Methods and analysis: This cross-sectional data linkage study involves 15 954 children (0–15 years), young adults (16–24 years), adults (25–64 years) and older adults (65+years) from the Perth metropolitan region who completed the Health and Wellbeing Surveillance System survey administered by the Department of Health of Western Australia from 2003 to 2009. Survey data were linked to Western Australia's (WA) Hospital Morbidity Database System (hospital admission) and Mental Health Information System (mental health system outpatient) data. Participants’ residential address was geocoded and features of their ‘neighbourhood’ were measured using Geographic Information Systems software. Associations between the built environment and self-reported and clinical health outcomes will be explored across varying geographic scales and life stages. Ethics and dissemination: The University of Western Australia's Human Research Ethics Committee and the Department of Health of Western Australia approved the study protocol (#2010/1). Findings will be published in peer-reviewed journals and presented at local, national and international conferences, thus contributing to the evidence base informing the design of healthy neighbourhoods for all residents.

Perceptions of the built environment and associations with walking among retirement village residents

Housing options, such as retirement villages, that promote and encourage healthy behaviors are needed to accommodate the growing older adult population. To examine how environmental perceptions relate to walking, residents of retirement villages in Perth, Australia, were sampled, and associations between a wide range of village and neighborhood environmental attributes and walking leisurely, briskly, and for transport were examined. Perceived village features associated with walking included aesthetics (odds ratio [OR] = 1.72), personal safety (OR = 0.43), and services and facilities (OR = 0.80), whereas neighborhood attributes included fewer physical barriers (OR = 1.37) and proximate destinations (OR = 1.93). Findings suggest that locating retirement villages in neighborhoods with many local destinations may encourage more walking than providing many services and facilities within villages. Indeed, safe villages rich with amenities were shown to be related to less walking in residents. These findings have implications for the location, design, and layout of retirement villages.

Exploring socioecological correlates of active living in retirement village residents

This study explored individual, social, and built environmental attributes in and outside of the retirement village setting and associations with various active living outcomes including objectively measured physical activity, specific walking behaviors, and social participation. Residents in Perth, Australia (N = 323), were surveyed on environmental perceptions of the village and surrounding neighborhood, self-reported physical activity, and demographic characteristics and wore accelerometers. Managers (N = 32) were surveyed on village characteristics, and objective neighborhood measures were generated in a Geographic Information System (GIS). Results indicated that built- and social-environmental attributes within and outside of retirement villages were associated with active living among residents; however, salient attributes varied depending on the specific outcome considered. Findings suggest that locating villages close to destinations is important for walking and that locating them close to previous and familiar neighborhoods is important for social participation. Further understanding and consideration into retirement village designs that promote both walking and social participation are needed.

Examining correlates of self-reported and objectively measured physical activity among retirement village residents

Aim Physical activity (PA) patterns of retirement village residents were investigated using self-report and objective measures. Methods Residents (n = 323) from retirement villages in Perth, Australia, were surveyed on PA behaviour and various demographic, residency, health-related and mobility factors. Most participants wore accelerometers for 7 days. Retirement village managers (n = 32) were surveyed on village descriptive characteristics, including the provision of amenities and facilities. Logistic regression models examined village and resident characteristics associated with PA. Results Based on objective measurement, only 27.1% of participants were sufficiently active (n = 288). Walking was one of the most popular PA modes. Few village characteristics were associated with PA; however, villages located in more walkable neighbourhoods increased participants’ odds of transport walking. Travelling outside the village daily also increased PA odds. Conclusions Most residents were insufficiently active to gain health benefits. Considering individual and environmental factors, within the retirement village and neighbourhood settings, and associations with PA, warrants attention.

The 2013 creative industries statistical analysis for Western Australia

The Department of Culture and the Arts undertook the first mapping of Perth’s creative industries in 2007 in partnership with the City of Perth and the Departments of Industry and Resources and the Premier and Cabinet. The 2013 Creative Industries Statistical Analysis for Western Australia report has updated the mapping with the 2011 Census employment data to provide invaluable information for the State’s creative industries, their peak associations and potential investors. The report maps sector employment numbers and growth between the 2006 and 2011 Census in the areas of music, visual and performing arts, film, TV and radio, advertising and marketing, software and digital content, publishing, and architecture and design, which includes designer fashion.

Informing healthy building design with biophilic urbanism design principles : a review and synthesis of current knowledge and research

Links between human health and wellbeing, and contact with nature are well understood in the fields of health and psychology, and more recently are gaining attention in the built environment industry. In 1984, E.O. Wilson coined the term ‘biophilia’ to describe the tendency for humans to have an innately emotional response to other living organisms. A growing number of researchers around the world are now exploring the impact of nature in urban environments (i.e. biophilic urbanism) on the human condition, including many indicators of human physical and mental health, recovery and performance. There is also an emergence of research on the potential for biophilic urbanism to address other challenges related to climate change mitigation and adaptation. This paper presents key findings from a review of key literature to date, discussing opportunities for biophilic urbanism to both improve occupant experience and performance, as well as addressing other sustainability objectives including climate change mitigation and adaptation. The paper presents an emerging framework for considering biophilic design opportunities and highlights implications for the built environment industry. This research draws on an Australian project considering biophilic urbanism in the response to climate change, within the Sustainable Built Environment National Research Centre. This includes findings from a literature review, a survey pilot study and two workshops undertaken in Perth and Brisbane with a variety of industry and government stakeholders.