556 resultados para Risky behaviour
Resumo:
The black rat (Rattus rattus) has been shown to be the primary species responsible for causing significant crop losses within the Australian macadamia industry. This species success within macadamia orchards is directly related to the flexibility expressed in its foraging behaviour. In this paper a conceptual foraging model is presented which proposes that the utilisation of resources by rodents within various components of the system is related not only to their relative abundance, but also to predator avoidance behaviour. Nut removal from high predation risk habitats during periods of low resource abundance in low risk compartments of the system is considered an essential behaviour that allows high rodent densities to be maintained throughout the year.
Resumo:
The purpose of this paper is to examine the legal implications of the continuing rise in the number of school children diagnosed with behaviour disorders. Not only are teachers now subject to a dense grid of legal regulation, they are also increasingly vulnerable to actions in tort. It will be argued here that as more and more children are labelled ‘disordered’, then the concomitant duty of care requirements for teachers becomes more onerous. As a consequence, teachers are less likely to be able to defend themselves against claims of negligence. It is concluded that while the schooling system needs to retain a healthy scepticism about each new pathologising disorder that seeks special status for its sufferers, it also needs to provide greater training and resources for teachers regarding disorder management. It is also concluded that recent changes to negligence law regarding the issue of ‘reasonable foreseeability’ within breach of duty of care, may not be as significant as might have been hoped by the teaching community. Indeed, the elevated standard of care, as required by increasing numbers of disordered pupils, place teachers in an ever more difficult legal position.
Resumo:
Despite the increasing popularity of social networking websites (SNWs), very little is known about the psychosocial variables which predict people’s use of these websites. The present study used an extended model of the theory of planned behaviour (TPB), including the additional variables of self-identity and belongingness, to predict high level SNW use intentions and behaviour in a sample of young people aged between 17 and 24 years. Additional analayses examined the impact of self-identity and belongingness on young people’s addictive tendencies towards SNWs. University students (N = 233) completed measures of the standard TPB constructs (attitude, subjective norm and perceived behavioural control), the additional predictor variables (self-identity and belongingness), demographic variables (age, gender, and past behaviour) and addictive tendencies. One week later, they reported their engagement in high level SNW use during the previous week. Regression analyses partially supported the TPB, as attitude and subjective norm signficantly predicted intentions to engage in high level SNW use with intention signficantly predicting behaviour. Self-identity, but not belongingness, signficantly contributed to the prediction of intention, and, unexpectedly, behaviour. Past behaviour also signficantly predicted intention and behaviour. Self-identity and belongingness signficantly predicted addictive tendencies toward SNWs. Overall, the present study revealed that high level SNW use is influenced by attitudinal, normative, and self-identity factors, findings which can be used to inform strategies that aim to modify young people’s high levels of use or addictive tendencies for SNWs.
Resumo:
Understanding the complex dynamic and uncertain characteristics of organisational employees who perform authorised or unauthorised information security activities is deemed to be a very important and challenging task. This paper presents a conceptual framework for classifying and organising the characteristics of organisational subjects involved in these information security practices. Our framework expands the traditional Human Behaviour and the Social Environment perspectives used in social work by identifying how knowledge, skills and individual preferences work to influence individual and group practices with respect to information security management. The classification of concepts and characteristics in the framework arises from a review of recent literature and is underpinned by theoretical models that explain these concepts and characteristics. Further, based upon an exploratory study of three case organisations in Saudi Arabia involving extensive interviews with senior managers, department managers, IT managers, information security officers, and IT staff; this article describes observed information security practices and identifies several factors which appear to be particularly important in influencing information security behaviour. These factors include values associated with national and organisational culture and how they manifest in practice, and activities related to information security management.
Resumo:
This study explored the role of donor prototype evaluations (perceptions of the typical organ donor) in organ donation communication decisions using an extended theory of planned behaviour (TPB) model. The model incorporated attitude, subjective norm, perceived behavioural control, moral norm, self-identity, and donor prototype evaluations to predict intentions to record consent on an organ donor register and discuss the organ donation decision with significant others. Participants completed surveys assessing the extended TPB constructs related to registering (n = 359) and discussing (n = 282). Results supported a role for donor prototype evaluations in predicting discussing intentions only. Both extended TPB structural equation models were a good fit to the data, accounting for 74 and 76% of the variance in registering and discussing intentions, respectively. Participants’ self-reported discussing behaviour (but not registering behaviour given low numbers of behavioural performers) was assessed 4 weeks later, with discussing intention as the only significant predictor of behaviour (Nagelkerke R2 = 0.11). These findings highlight the impact of people's perceptions of a typical donor on their decisions to discuss their organ donation preference, assisting our understanding of the factors influencing individuals' communication processes in efforts to bridge the gap between organ supply and demand.
Resumo:
Cold-formed steel members have been widely used in residential, industrial and commercial buildings as primary load bearing structural elements and non-load bearing structural elements (partitions) due to their advantages such as higher strength to weight ratio over the other structural materials such as hot-rolled steel, timber and concrete. Cold-formed steel members are often made from thin steel sheets and hence they are more susceptible to various buckling modes. Generally short columns are susceptible to local or distortional buckling while long columns to flexural or flexural-torsional buckling. Fire safety design of building structures is an essential requirement as fire events can cause loss of property and lives. Therefore it is essential to understand the fire performance of light gauge cold-formed steel structures under fire conditions. The buckling behaviour of cold-formed steel compression members under fire conditions is not well investigated yet and hence there is a lack of knowledge on the fire performance of cold-formed steel compression members. Current cold-formed steel design standards do not provide adequate design guidelines for the fire design of cold-formed steel compression members. Therefore a research project based on extensive experimental and numerical studies was undertaken at the Queensland University of Technology to investigate the buckling behaviour of light gauge cold-formed steel compression members under simulated fire conditions. As the first phase of this research, a detailed review was undertaken on the mechanical properties of light gauge cold-formed steels at elevated temperatures and the most reliable predictive models for mechanical properties and stress-strain models based on detailed experimental investigations were identified. Their accuracy was verified experimentally by carrying out a series of tensile coupon tests at ambient and elevated temperatures. As the second phase of this research, local buckling behaviour was investigated based on the experimental and numerical investigations at ambient and elevated temperatures. First a series of 91 local buckling tests was carried out at ambient and elevated temperatures on lipped and unlipped channels made of G250-0.95, G550-0.95, G250-1.95 and G450-1.90 cold-formed steels. Suitable finite element models were then developed to simulate the experimental conditions. These models were converted to ideal finite element models to undertake detailed parametric study. Finally all the ultimate load capacity results for local buckling were compared with the available design methods based on AS/NZS 4600, BS 5950 Part 5, Eurocode 3 Part 1.2 and the direct strength method (DSM), and suitable recommendations were made for the fire design of cold-formed steel compression members subject to local buckling. As the third phase of this research, flexural-torsional buckling behaviour was investigated experimentally and numerically. Two series of 39 flexural-torsional buckling tests were undertaken at ambient and elevated temperatures. The first series consisted 2800 mm long columns of G550-0.95, G250-1.95 and G450-1.90 cold-formed steel lipped channel columns while the second series contained 1800 mm long lipped channel columns of the same steel thickness and strength grades. All the experimental tests were simulated using a suitable finite element model, and the same model was used in a detailed parametric study following validation. Based on the comparison of results from the experimental and parametric studies with the available design methods, suitable design recommendations were made. This thesis presents a detailed description of the experimental and numerical studies undertaken on the mechanical properties and the local and flexural-torsional bucking behaviour of cold-formed steel compression member at ambient and elevated temperatures. It also describes the currently available ambient temperature design methods and their accuracy when used for fire design with appropriately reduced mechanical properties at elevated temperatures. Available fire design methods are also included and their accuracy in predicting the ultimate load capacity at elevated temperatures was investigated. This research has shown that the current ambient temperature design methods are capable of predicting the local and flexural-torsional buckling capacities of cold-formed steel compression members at elevated temperatures with the use of reduced mechanical properties. However, the elevated temperature design method in Eurocode 3 Part 1.2 is overly conservative and hence unsuitable, particularly in the case of flexural-torsional buckling at elevated temperatures.
Resumo:
Describes a brief intensive program of cognitive therapy for depression that was designed for 4 adult residents of country towns in Australia, who resided some distance from treatment centers. Ss were assessed prior to treatment, at posttreatment, and at 4-wk, 8-wk, and 20-mo follow-ups. Treatments took place over 3 consecutive days for a total period of 15 hrs. Effects were highly consistent with the impact of group treatments delivered on a more traditional schedule. If confirmed in a controlled group study, these results suggest that cognitive therapy may be applied more economically and more widely than was previously realized.
Resumo:
This paper explores how visibly non-heteronormative bodies mediate policing experiences of LGBT (lesbian, gay, bisexual, transgender) young people, an area that has been mostly ignored in research about policing young people. Informed by interviews with 35 LGBT young people in Brisbane, Queensland, this paper addresses this gap by exploring how the non-heteronormative body mediates policing experiences of LGBT young people. Drawing on Foucault (1984), Butler (1990a), and other queer theory, the paper argues young non-heteronormative bodies visibly perform ‘queerness’, are read by police, and shape police-LGBT youth interactions. While this is complicated by looking at-risk (in terms of risk factors like homelessness, substance abuse), and looking risky (in terms of risk-taking or criminalised activities), the paper concludes noting how youthful LGBT bodies are regulated by police as non-heteronormative and deviant.
Resumo:
Despite all attempts to prevent fraud, it continues to be a major threat to industry and government. Traditionally, organizations have focused on fraud prevention rather than detection, to combat fraud. In this paper we present a role mining inspired approach to represent user behaviour in Enterprise Resource Planning (ERP) systems, primarily aimed at detecting opportunities to commit fraud or potentially suspicious activities. We have adapted an approach which uses set theory to create transaction profiles based on analysis of user activity records. Based on these transaction profiles, we propose a set of (1) anomaly types to detect potentially suspicious user behaviour and (2) scenarios to identify inadequate segregation of duties in an ERP environment. In addition, we present two algorithms to construct a directed acyclic graph to represent relationships between transaction profiles. Experiments were conducted using a real dataset obtained from a teaching environment and a demonstration dataset, both using SAP R/3, presently the most predominant ERP system. The results of this empirical research demonstrate the effectiveness of the proposed approach.
Resumo:
This thesis by publication contributes to our knowledge of psychological factors underlying a modern day phenomenon, young people’s mobile phone behaviour. Specifically, the thesis reports a PhD program of research which adopted a social psychological approach to explore mobile phone behaviour among young Australians aged between 15 and 24 years. A particular focus of the research program was to explore both the cognitive and behavioural aspects of young people’s mobile phone behaviour which for the purposes of this thesis is defined as mobile phone involvement. The research program comprised three separate stages which were developmental in nature, in that, the findings of each stage of the research program informed the next. The overarching goal of the program of research was to improve our understanding of the psychosocial factors influencing young people’s mobile phone behaviour. To achieve this overall goal, there were a number of aims to the research program which reflect the developmental nature of this thesis. Given the limited research into the mobile phone behaviour in Australia, the first two aims of the research program were to explore patterns of mobile phone behaviour among Australian youth and explore the social psychological factors relating to their mobile phone behaviour. Following this exploration, the research program sought to develop a measure which captures the cognitive and behavioural aspects of mobile phone behaviour. Finally, the research program aimed to examine and differentiate the psychosocial predictors of young people’s frequency of mobile phone use and their level of involvement with their mobile phone. Both qualitative and quantitative methodologies were used throughout the program of research. Five papers prepared during the three stages of the research program form the bulk of this thesis. The first stage of the research program was a qualitative investigation of young people’s mobile phone behaviour. Thirty-two young Australians participated in a series of focus groups in which they discussed their mobile phone behaviour. Thematic data analysis explored patterns of mobile phone behaviour among young people, developed an understanding of psychological factors influencing their use of mobile phones, and identified that symptoms of addiction were emerging in young people’s mobile phone behaviour. Two papers (Papers 1 and 2) emanated from this first stage of the research program. Paper 1 explored patterns of mobile phone behaviour and revealed that mobile phones were perceived as being highly beneficial to young people’s lives, with the ability to remain in constant contact with others being particularly valued. The paper also identified that symptoms of behavioural addiction including withdrawal, cognitive and behavioural salience, and loss of control, emerged in participants’ descriptions of their mobile phone behaviour. Paper 2 explored how young people’s need to belong and their social identity (two constructs previously unexplored in the context of mobile phone behaviour) related to their mobile phone behaviour. It was revealed that young people use their mobile phones to facilitate social attachments. Additionally, friends and peers influenced young people’s mobile phone behaviour; for example, their choice of mobile phone carrier and their most frequent type of mobile phone use. These papers laid the foundation for the further investigation of addictive patterns of behaviour and the role of social psychological factors on young people’s mobile behaviour throughout the research program. Stage 2 of the research program focussed on developing a new parsimonious measure of mobile phone behaviour, the Mobile Phone Involvement Questionnaire (MPIQ), which captured the cognitive and behavioural aspects of mobile phone use. Additionally, the stage included a preliminary exploration of factors influencing young people’s mobile phone behaviour. Participants (N = 946) completed a questionnaire which included a pool of items assessing symptoms of behavioural addiction, the uses and gratifications relating to mobile phone use, and self-identity and validation from others in the context of mobile phone behaviour. Two papers (Papers 3 & 4) emanated from the second stage of the research program. Paper 3 provided an important link between the qualitative and quantitative components of the research program. Qualitative data from Stage 1 indicated the reasons young people use their mobile phones and identified addictive characteristics present in young people’s mobile phone behaviour. Results of the quantitative study conducted in Stage 2 of the research program revealed the uses and gratifications relating to young people’s mobile phone behaviour and the effect of these gratifications on young people’s frequency of mobile phone use and three indicators of addiction, withdrawal, salience, and loss of control. Three major uses and gratifications: self (such as feeling good or as a fashion item), social (such as contacting friends), and security (such as use in an emergency) were found to underlie much of young people’s mobile phone behaviour. Self and social gratifications predicted young people’s frequency of mobile phone use and the three indicators of addiction but security gratifications did not. These results provided an important foundation for the inclusion of more specific psychosocial predictors in the later stages of the research program. Paper 4 reported the development of the mobile phone involvement questionnaire and a preliminary exploration of the effect of self-identity and validation from others on young people’s mobile phone behaviour. The MPIQ assessed a unitary construct and was a reliable measure amongst this cohort. Results found that self-identity influenced the frequency of young people’s use whereas self-identity and validation from others influenced their level of mobile phone involvement. These findings provided an important indication that, in addition to self factors, other people have a strong influence on young people’s involvement with their mobile phone and that mobile phone involvement is conceptually different to frequency of mobile phone use. Stage 3 of the research program empirically examined the psychosocial predictors of young people’s mobile behaviour and one paper, Paper 5, emanated from this stage. Young people (N = 292) from throughout Australia completed an online survey assessing the role of self-identity, ingroup norm, the need to belong, and self-esteem on their frequency of mobile phone use and their mobile phone involvement. Self-identity was the only psychosocial predictor of young people’s frequency of mobile phone use. In contrast, self-identity, ingroup norm, and need to belong all influenced young people’s level of involvement with their mobile phone. Additionally, the effect of self-esteem on young people’s mobile phone involvement was mediated by their need to belong. These results indicate that young people who perceive their mobile phone to be an integral part of their self-identity, who perceive that mobile phone is common amongst friends and peers, and who have a strong need for attachment to others, in some cases driven by a desire to enhance their self-esteem, are most likely to become highly involved with their mobile phones. Overall, this PhD program of research has provided an important contribution to our understanding of young Australians’ mobile phone behaviour. Results of the program have broadened our knowledge of factors influencing mobile phone behaviour beyond the approaches used in previous research. The use of various social psychological theories combined with a behavioural addiction framework provided a novel examination of young people’s mobile behaviour. In particular, the development of a new measure of mobile phone behaviour in the research program facilitated the differentiation of the psychosocial factors influencing frequency of young people’s mobile phone behaviour and their level of involvement with their mobile phone. Results of the research program indicate the important role that mobile phone behaviour plays in young people’s social development and also signals the characteristics of those people who may become highly involved with their mobile phone. Future research could build on this thesis by exploring whether mobile phones are affecting traditional social psychological processes and whether the results in this research program are generalisable to other cohorts and other communication technologies.
Resumo:
Until recently, the hot-rolled steel members have been recognized as the most popular and widely used steel group, but in recent times, the use of cold-formed high strength steel members has rapidly increased. However, the structural behavior of light gauge high strength cold-formed steel members characterized by various buckling modes is not yet fully understood. The current cold-formed steel sections such as C- and Z-sections are commonly used because of their simple forming procedures and easy connections, but they suffer from certain buckling modes. It is therefore important that these buckling modes are either delayed or eliminated to increase the ultimate capacity of these members. This research is therefore aimed at developing a new cold-formed steel beam with two torsionally rigid rectangular hollow flanges and a slender web formed using intermittent screw fastening to enhance the flexural capacity while maintaining a minimum fabrication cost. This thesis describes a detailed investigation into the structural behavior of this new Rectangular Hollow Flange Beam (RHFB), subjected to flexural action The first phase of this research included experimental investigations using thirty full scale lateral buckling tests and twenty two section moment capacity tests using specially designed test rigs to simulate the required loading and support conditions. A detailed description of the experimental methods, RHFB failure modes including local, lateral distortional and lateral torsional buckling modes, and moment capacity results is presented. A comparison of experimental results with the predictions from the current design rules and other design methods is also given. The second phase of this research involved a methodical and comprehensive investigation aimed at widening the scope of finite element analysis to investigate the buckling and ultimate failure behaviours of RHFBs subjected to flexural actions. Accurate finite element models simulating the physical conditions of both lateral buckling and section moment capacity tests were developed. Comparison of experimental and finite element analysis results showed that the buckling and ultimate failure behaviour of RHFBs can be simulated well using appropriate finite element models. Finite element models simulating ideal simply supported boundary conditions and a uniform moment loading were also developed in order to use in a detailed parametric study. The parametric study results were used to review the current design rules and to develop new design formulae for RHFBs subjected to local, lateral distortional and lateral torsional buckling effects. Finite element analysis results indicate that the discontinuity due to screw fastening has a noticeable influence only for members in the intermediate slenderness region. Investigations into different combinations of thicknesses in the flange and web indicate that increasing the flange thickness is more effective than web thickness in enhancing the flexural capacity of RHFBs. The current steel design standards, AS 4100 (1998) and AS/NZS 4600 (1996) are found sufficient to predict the section moment capacity of RHFBs. However, the results indicate that the AS/NZS 4600 is more accurate for slender sections whereas AS 4100 is more accurate for compact sections. The finite element analysis results further indicate that the current design rules given in AS/NZS 4600 is adequate in predicting the member moment capacity of RHFBs subject to lateral torsional buckling effects. However, they were inadequate in predicting the capacities of RHFBs subject to lateral distortional buckling effects. This thesis has therefore developed a new design formula to predict the lateral distortional buckling strength of RHFBs. Overall, this thesis has demonstrated that the innovative RHFB sections can perform well as economically and structurally efficient flexural members. Structural engineers and designers should make use of the new design rules and the validated existing design rules to design the most optimum RHFB sections depending on the type of applications. Intermittent screw fastening method has also been shown to be structurally adequate that also minimises the fabrication cost. Product manufacturers and builders should be able to make use of this in their applications.
Resumo:
Overweight and obesity are two of the most important emerging public health issues in our time and regarded by the World Health Organisation [WHO] (1998) as a worldwide epidemic. The prevalence of obesity in the USA is the highest in the world, and Australian obesity rates fall into second place. Currently, about 60% of Australian adults are overweight (BMI „d 25kg/m2). The socio-demographic factors associated with overweight and/or obesity have been well demonstrated, but many of the existing studies only examined these relationships at one point of time, and did not examine whether significant relationships changed over time. Furthermore, only limited previous research has examined the issue of the relationship between perception of weight status and actual weight status, as well as factors that may impact on people¡¦s perception of their body weight status. Aims: The aims of the proposed research are to analyse the discrepancy between perceptions of weight status and actual weight status in Australian adults; to examine if there are trends in perceptions of weight status in adults between 1995 to 2004/5; and to propose a range of health promotion strategies and furth er research that may be useful in managing physical activity, healthy diet, and weight reduction. Hypotheses: Four alternate hypotheses are examined by the research: (1) there are associations between independent variables (e.g. socio -demographic factors, physical activity and dietary habits) and overweight and/or obesity; (2) there are associations between the same independent variables and the perception of overweight; (3) there are associations between the same independent variables and the discrepancy between weight status and perception of weight status; and (4) there are trends in overweight and/or obesity, perception of overweight, and the discrepancy in Australian adults from 1995 to 2004/5. Conceptual Framework and Methods: A conceptual framework is developed that shows the associations identified among socio -demographic factors, physical activity and dietary habits with actual weight status, as well as examining perception of weight status. The three latest National Health Survey data bases (1995 , 2001 and 2004/5) were used as the primary data sources. A total of 74,114 Australian adults aged 20 years and over were recruited from these databases. Descriptive statistics, bivariate analyses (One -Way ANOVA tests, unpaired t-tests and Pearson chi-square tests), and multinomial logistic regression modelling were used to analyse the data. Findings: This research reveals that gender, main language spoken at home, occupation status, household structure, private health insurance status, and exercise are related to the discrepancy between actual weight status and perception of weight status, but only gender and exercise are related to the discrepancy across the three time point s. The current research provides more knowledge about perception of weight status independently. Factors which affect perception of overweight are gender, age, language spoken at home, private health insurance status, and diet ary habits. The study also finds that many factors that impact overweight and/or obesity also have an effect on perception of overweight, such as age, language spoken at home, household structure, and exercise. However, some factors (i.e. private health insurance status and milk consumption) only impact on perception of overweight. Furthermore, factors that are rel ated to people’s overweight are not totally related to people’s underestimation of their body weight status in the study results. Thus, there are unknown factors which can affect people’s underestimation of their body weight status. Conclusions: Health promotion and education activities should provide education about population health education and promotion and education for particular at risk sub -groups. Further research should take the form of a longitudinal study design ed to examine the causal relationship between overweight and/or obesity and underestimation of body weight status, it should also place more attention on the relationships between overweight and/or obesity and dietary habits, with a more comprehensive representation of SES. Moreover, further research that deals with identification of characteristics about perception of weight status, in particular the underestimation of body weight status should be undertaken.
Resumo:
This paper presents the measurements of strain and the subsequent stress analysis on an in-service cast iron water main buried in reactive soil. The results indicate that the pipe crown experienced predominantly tensile stresses during drying in summer and, subsequently, these stresses reduce, eventually leading to compressive stresses as the soil swells with increase in moisture content with the approach of winter. It is also evident that flexural movement caused by thermal stresses and soil pressure has led to downward bending of the pipe in summer and subsequent upward movement in winter. The limited data collected from pipe strains and strengths indicate that it is possible for pipe capacity to be exceeded by thermal and soil stresses leading to pipe failure, provided the pipe has undergone significant corrosion.
Resumo:
Functional communication training was used to replace multiply determined problem behaviour in two boys with autism. Experiment 1 involved a functional analysis of several topographies of problem behaviour using a variation of the procedures described by Iwata, Dorsey, Slifer, Bauman, and Richman. Results suggested that aggression, self-injury, and disruption were multiply determined (i.e., maintained by both attention and access to preferred objects). Experiment 2 involved a multiple-baseline design across subjects. The focus of intervention was to replace aggression, self-injury, and disruption with functionally equivalent communicative alternatives. Both boys were taught alternative “mands” to recruit attention and request preferred objects. Acquisition of these alternative communication skills was associated with concurrent decreases in aggression, self-injury, and disruption. Results suggest that multiply determined challenging behaviour can be decreased by teaching an alternative communication skill to replace each assessed function of the problem behaviour.
A discrete-trial approach to the functional analysis of aggressive behaviour in two boys with autism
Resumo:
Intervention to reduce challenging behaviour may be enhanced when based on a prior functional analysis. The present study describes a discrete-trial approach for the functional analysis of aggressive behaviour in two boys with autism. Twenty brief assessment trials were conducted in the classroom by the teacher under each of three conditions (i.e., attention, task and tangible). The results showed a clear pattern to each child's aggressive behaviour and suggested logical intervention strategies, although the study is limited because it involved only two children. The discrete-trial approach would appear to represent a practical and ecologically valid technique for conducting a functional analysis of challenging behaviour in applied settings