Review of current test methods for screwed connections

The pull-through/local dimpling failure strength of screwed connections is very important in the design of profiled steel cladding systems to help them resist storms and hurricanes. The current American and European provisions recommend four different test methods for the screwed connections in tension, but the accuracy of these methods in determining the connection strength is not known. It is unlikely that the four test methods are equivalent in all cases and thus it is necessary to reduce the number of methods recommended. This paper presents a review of these test methods based on some laboratory tests on crest- and valley-fixed claddings and then recommends alternative tests methods that reproduce the real behavior of the connections, including the bending and membrane deformations of the cladding around the screw fasteners and the tension load in the fastener.

Distributed plasticity analysis of steel frame structures comprising non-compact sections

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. A primary objective was to produce a comprehensive range of new distributed plasticity analytical benchmark solutions for verification of the concentrated plasticity methods. A distributed plasticity model was developed using shell finite elements to explicitly account for the effects of gradual yielding and spread of plasticity, initial geometric imperfections, residual stresses and local buckling deformations. The model was verified by comparison with large-scale steel frame test results and a variety of existing analytical benchmark solutions. This paper presents a description of the distributed plasticity model and details of the verification study.

Food and Brisbane households : dietary, social and health consequences of food insecurity

Background & Aims: Access to sufficient amounts of safe and culturally-acceptable foods is a fundamental human right. Food security exists when all people, at all times, have physical, social, and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life. Food insecurity therefore occurs when the availability or access to sufficient amounts of nutritionally-adequate, culturally-appropriate and safe foods, or, the ability to acquire such foods in socially-acceptable ways, is limited. Food insecurity may result in significant adverse effects for the individual and these outcomes may vary between adults and children. Among adults, food insecurity may be associated with overweight or obesity, poorer self-rated general health, depression, increased health-care utilisation and dietary intakes less consistent with national recommendations. Among children, food insecurity may result in poorer self or parent-reported general health, behavioural problems, lower levels of academic achievement and poor social outcomes. The majority of research investigating the potential correlates of food insecurity has been undertaken in the United States (US), where regular national screening for food insecurity is undertaken using a comprehensive multi-item measurement. In Australia, screening for food insecurity takes place on a three yearly basis via the use of a crude, single-item included in the National Health Survey (NHS). This measure has been shown to underestimate the prevalence of food insecurity by 5%. From 1995 – 2004, the prevalence of food insecurity among the Australian population remained stable at 5%. Due to the perceived low prevalence of this issue, screening for food insecurity was not undertaken in the most recent NHS. Furthermore, there are few Australian studies investigating the potential determinants of food insecurity and none investigating potential outcomes among adults and children. This study aimed to examine these issues by a) investigating the prevalence of food insecurity among households residing in disadvantaged urban areas and comparing prevalence rates estimated by the more comprehensive 18-item and 6-item United States Department of Agriculture (USDA) Food Security Survey Module (FSSM) to those estimated by the current single-item measure used for surveillance in Australia and b) investigating the potential determinants and outcomes of food insecurity, Methods: A comprehensive literature review was undertaken to investigate the potential determinants and consequences of food insecurity among developed countries. This was followed by a cross-sectional study in which 1000 households from the most disadvantaged 5% of Brisbane areas were sampled and data collected via mail-based survey (final response rate = 53%, n = 505). Data were collected for food security status, sociodemographic characteristics (household income, education, age, gender, employment status, housing tenure and living arrangements), fruit and vegetable intakes, meat and take-away consumption, presence of depressive symptoms, presence of chronic disease and body mass index (BMI) among adults. Among children, data pertaining to BMI, parent-reported general health, days away from school and activities and behavioural problems were collected. Rasch analysis was used to investigate the psychometric properties of the 18-, 10- and 6-item adaptations of the USDA-FSSM, and McNemar's test was used to investigate the difference in the prevalence of food insecurity as measured by these three adaptations compared to the current single-item measure used in Australia. Chi square and logistic regression were used to investigate the differences in dietary and health outcomes among adults and health and behavioural outcomes among children. Results were adjusted for equivalised household income and, where necessary, for indigenous status, education and family type. Results: Overall, 25% of households in these urbanised-disadvantaged areas reported experiencing food insecurity; this increased to 34% when only households with children were analysed. The current reliance on a single-item measure to screen for food insecurity may underestimate the true burden among the Australian population, as this measure was shown to significantly underestimate the prevalence of food insecurity by five percentage points. Internationally, major potential determinants of food insecurity included poverty and indicators of poverty, such as low-income, unemployment and lower levels of education. Ethnicity, age, transportation and cooking and financial skills were also found to be potential determinants of food insecurity. Among Australian adults in disadvantaged urban areas, food insecurity was associated with a three-fold increase in experiencing poorer self-rated general health and a two-to-five-fold increase in the risk of depression. Furthermore, adults from food insecure households were twoto- three times more likely to have seen a general practitioner and/or been admitted to hospital within the previous six months, compared to their food secure counterparts. Weight status and intakes of fruits, vegetables and meat were not associated with food insecurity. Among Australian households with children, those in the lowest tertile were over 16 times more likely to experience food insecurity compared to those in the highest tertile for income. After adjustment for equivalised household income, children from food insecure households were three times more likely to have missed days away from school or other activities. Furthermore, children from food insecure households displayed a two-fold increase in atypical emotions and behavioural difficulties. Conclusions: Food insecurity is an important public health issue and may contribute to the burden on the health care system through its associations with depression and increased health care utilisation among adults and behavioural and emotional problems among children. Current efforts to monitor food insecurity in Australia do not occur frequently and use a tool that may underestimate the prevalence of food insecurity. Efforts should be made to improve the regularity of screening for food insecurity via the use of a more accurate screening measure. Most of the current strategies that aim to alleviate food insecurity do not sufficiently address the issue of insufficient financial resources for acquiring food; a factor which is an important determinant of food insecurity. Programs to address this issue should be developed in collaboration with groups at higher risk of developing food insecurity and should incorporate strategies to address the issue of low income as a barrier to food acquisition.

The effect of varied test instructions on neuropsychological performance following mild traumatic brain injury : an investigation of ‘diagnosis threat’

Diagnosis threat is a psychosocial factor that has been proposed to contribute to poor outcomes following mild traumatic brain injury (mTBI). This threat is thought to impair the cognitive test performance of individuals with mTBI because of negative injury stereotypes. University students (N= 45, 62.2% female) with a history of mTBI were randomly allocated to a diagnosis threat (DT, n=15), reduced threat (DT-reduced, n=15) or neutral (n=15) group. The reduced threat condition invoked a positive stereotype (i.e., that people with mTBI can perform well on cognitive tests). All participants were given neutral instructions before they completed baseline tests of: a) objective cognitive function across a number of domains; b) psychological symptoms; and, c) PCS symptoms, including self-reported cognitive and emotional difficulties. Participants then received either neutral, DT or DT-reduced instructions, before repeating the tests. Results were analyzed using separate mixed model ANOVAs; one for each dependent measure. The only significant result was for the 2 X 3 ANOVA on an objective test of attention/working memory, Digit Span, p<.05, such that the DT-reduced group performed better than the other groups, which were not different from each other. Although not consistent with predictions or earlier DT studies, the absence of group differences on most tests fits with several recent DT findings. The results of this study suggest that it is timely to reconsider the role of DT as a unique contributor to poor mTBI outcome.

Towards an integrated maturity model of asset management capabilities

Asset service organisations often recognize asset management as a core competence to deliver benefits to their business. But how do organizations know whether their asset management processes are adequate? Asset management maturity models, which combine best practices and competencies, provide a useful approach to test the capacity of organisations to manage their assets. Asset management frameworks are required to meet the dynamic challenges of managing assets in contemporary society. Although existing models are subject to wide variations in their implementation and sophistication, they also display a distinct weakness in that they tend to focus primarily on the operational and technical level and neglect the levels of strategy, policy and governance as well as the social and human resources – the people elements. Moreover, asset management maturity models have to respond to the external environmental factors, including such as climate change and sustainability, stakeholders and community demand management. Drawing on five dimensions of effective asset management – spatial, temporal, organisational, statistical, and evaluation – as identified by Amadi Echendu et al. [1], this paper carries out a comprehensive comparative analysis of six existing maturity models to identify the gaps in key process areas. Results suggest incorporating these into an integrated approach to assess the maturity of asset-intensive organizations. It is contended that the adoption of an integrated asset management maturity model will enhance effective and efficient delivery of services.

Effective punishment experiences : the need for a more comprehensive approach to conceptualising behavioural punishers and reinforcers in a road safety context

Determining what consequences are likely to serve as effective punishment for any given behaviour is a complex task. This chapter focuses specifically on illegal road user behaviours and the mechanisms used to punish and deter them. Traffic law enforcement has traditionally used the threat and/or receipt of legal sanctions and penalties to deter illegal and risky behaviours. This process represents the use of positive punishment, one of the key behaviour modification mechanisms. Behaviour modification principles describe four types of reinforcers: positive and negative punishments and positive and negative reinforcements. The terms ‘positive’ and ‘negative’ are not used in an evaluative sense here. Rather, they represent the presence (positive) or absence (negative) of stimuli to promote behaviour change. Punishments aim to inhibit behaviour and reinforcements aim to encourage it. This chapter describes a variety of punishments and reinforcements that have been and could be used to modify illegal road user behaviours. In doing so, it draws on several theoretical perspectives that have defined behavioural reinforcement and punishment in different ways. Historically, the main theoretical approach used to deter risky road use has been classical deterrence theory which has focussed on the perceived certainty, severity and swiftness of penalties. Stafford and Warr (1993) extended the traditional deterrence principles to include the positive reinforcement concept of punishment avoidance. Evidence of the association between punishment avoidance experiences and behaviour has been established for a number of risky road user behaviours including drink driving, unlicensed driving, and speeding. We chose a novel way of assessing punishment avoidance by specifying two sub-constructs (detection evasion and punishment evasion). Another theorist, Akers, described the idea of competing reinforcers, termed differential reinforcement, within social learning theory (1977). Differential reinforcement describes a balance of reinforcements and punishments as influential on behaviour. This chapter describes comprehensive way of conceptualising a broad range of reinforcement and punishment concepts, consistent with Akers’ differential reinforcement concept, within a behaviour modification framework that incorporates deterrence principles. The efficacy of three theoretical perspectives to explain self-reported speeding among a sample of 833 Australian car drivers was examined. Results demonstrated that a broad range of variables predicted speeding including personal experiences of evading detection and punishment for speeding, intrinsic sensations, practical benefits expected from speeding, and an absence of punishing effects from being caught. Not surprisingly, being younger was also significantly related to more frequent speeding, although in a regression analysis, gender did not retain a significant influence once all punishment and reinforcement variables were entered. The implications for speed management, as well as road user behaviour modification more generally, are discussed in light of these findings. Overall, the findings reported in this chapter suggest that a more comprehensive approach is required to manage the behaviour of road users which does not rely solely on traditional legal penalties and sanctions.

Double strap joint tests to determine the bond characteristics between CFRP and steel plates

Advanced composite materials offer remarkable potential in the upgrade of civil engineering structures. The evolution of CFRP (carbon fibre reinforced polymer) technologies and their versatility for applications in civil constructions require comprehensive and reliable codes of practice. Guidelines are available on the rehabilitation and retrofit of concrete structures with advanced composite materials. However, there is a need to develop appropriate design guidelines for CFRP strengthened steel structures. It is important to understand the bond characteristics between CFRP and steel plates. This paper describes a series of double strap shear tests loaded in tension to investigate the bond between CFRP sheets and steel plates. Both normal modulus (240 GPa) and high modulus (640 GPa) CFRPs were used in the test program. Strain gauges were mounted to capture the strain distribution along the CFRP length. Different failure modes were observed for joints with normal modulus CFRP and those with high modulus CFRP. The strain distribution along the CFRP length is similar for the two cases. A shorter effective bond length was obtained for joints with high modulus CFRP whereas larger ultimate load carrying capacity can be achieved for joints with normal modulus CFRP when the bond length is long enough.

Perceptions of organ donors and willingness to donate organs upon death : a test of the prototype/willingness model

Understanding people's organ donation decisions may narrow the gap between organ supply and demand. In two studies, participants who had not recorded their posthumous organ donation decision (Study 1, N = 210; Study 2, N = 307) completed items assessing prototype/willingness model (PWM; attitude, subjective norm, donor prototype favorability and similarity, willingness) constructs. Attitude, subjective norm, and prototype similarity predicted willingness to donate. Prototype favorability and a Prototype Favorability × Similarity interaction predicted willingness (Study 2). These findings provide support for the PWM in altruistic health contexts, highlighting the importance of people's perceptions about organ donors in their donation decisions.

Internet-enabled tourism entrepreneurs. International entrepreneurial values elicited through repertory test and laddering analysis

Although the tourism industry has been dramatically altered due to the Internet, there has been limited research published about international entrepreneurial values and Internet use in tourism firms. The findings of this study point to a relationship between the values of Internet-enabled international entrepreneurs in small-sized to medium-sized enterprises and the inclination of the firm to develop and initiate international activity. The findings of this study suggest that Internet-enabled tourism entrepreneurs share similar construct values. Two effective but underutilized qualitative methods were used in this study. The first method, repertory test, is an efficient technique for exploring constructs in decision making; the second method, laddering analysis, facilitates understanding of the perceived consequences and personal values guiding behaviour.

Establishing definitions and modeling public transport travel time variability

Public transport travel time variability (PTTV) is essential for understanding deteriorations in the reliability of travel time, optimizing transit schedules and route choices. This paper establishes key definitions of PTTV in which firstly include all buses, and secondly include only a single service from a bus route. The paper then analyses the day-to-day distribution of public transport travel time by using Transit Signal Priority data. A comprehensive approach using both parametric bootstrapping Kolmogorov-Smirnov test and Bayesian Information Creation technique is developed, recommends Lognormal distribution as the best descriptor of bus travel time on urban corridors. The probability density function of Lognormal distribution is finally used for calculating probability indicators of PTTV. The findings of this study are useful for both traffic managers and statisticians for planning and researching the transit systems.

Response of a buried tunnel to surface blast using different numerical techniques

This paper presents a comparative study on the response of a buried tunnel to surface blast using the arbitrary Lagrangian-Eulerian (ALE) and smooth particle hydrodynamics (SPH) techniques. Since explosive tests with real physical models are extremely risky and expensive, the results of a centrifuge test were used to validate the numerical techniques. The numerical study shows that the ALE predictions were faster and closer to the experimental results than those from the SPH simulations which over predicted the strains. The findings of this research demonstrate the superiority of the ALE modelling techniques for the present study. They also provide a comprehensive understanding of the preferred ALE modelling techniques which can be used to investigate the surface blast response of underground tunnels.

Useful field of view test

A test of the useful field of view was introduced more than two decades ago and was designed to reflect the visual difficulties that older adults experience with everyday tasks. Importantly, the useful field of view is one of the most extensively researched and promising predictor tests for a range of driving outcomes measures, including driving ability and crash risk, as well as other everyday tasks. Currently available commercial versions of the test can be administered using personal computers and measure speed of visual processing speed for rapid detection and localization of targets under conditions of divided visual attention and in the presence and absence of visual clutter. The test is believed to assess higher order cognitive abilities, but performance also relies on visual sensory function since targets must be visible in order to be attended to. The format of the useful field of view test has been modified over the years; the original version estimated the spatial extent of useful field of view, while the latest versions measures visual processing speed. While deficits in the useful field of view are associated with functional impairments in everyday activities in older adults, there is also emerging evidence from several research groups that improvements in visual processing speed can be achieved through training. These improvements have been shown to reduce crash risk, and have a positive impact on health and functional well being, with the potential to increase the mobility and hence independence of older adults.

Comprehensive Addictive Behaviors and Disorders, Volume 1 : Principles of Addiction

"Principles of Addiction provides a solid understanding of the definitional and diagnostic differences between use, abuse, and disorder. It describes in great detail the characteristics of these syndromes and various etiological models. The book's three main sections examine the nature of addiction, including epidemiology, symptoms, and course; alcohol and drug use among adolescents and college students; and detailed descriptions of a wide variety of addictive behaviors and disorders, encompassing not only drugs and alcohol, but caffeine, food, gambling, exercise, sex, work, social networking, and many other areas. This volume is especially important in providing a basic introduction to the field as well as an in-depth review of our current understanding of the nature and process of addictive behaviors. Principles of Addiction is one of three volumes comprising the 2,500-page series, Comprehensive Addictive Behaviors and Disorders. This series provides the most complete collection of current knowledge on addictive behaviors and disorders to date. In short, it is the definitive reference work on addictions."--publisher website

Comprehensive Addictive Behaviors and Disorders, Volume 2 : Biological Research on Addiction

"Biological Research on Addiction examines the neurobiological mechanisms of drug use and drug addiction, describing how the brain responds to addictive substances as well as how it is affected by drugs of abuse. The book's four main sections examine behavioral and molecular biology; neuroscience; genetics; and neuroimaging and neuropharmacology as they relate to the addictive process. This volume is especially effective in presenting current knowledge on the key neurobiological and genetic elements in an individual's susceptibility to drug dependence, as well as the processes by which some individuals proceed from casual drug use to drug dependence. Biological Research on Addiction is one of three volumes comprising the 2,500-page series, Comprehensive Addictive Behaviors and Disorders. This series provides the most complete collection of current knowledge on addictive behaviors and disorders to date. In short, it is the definitive reference work on addictions."--publisher website