Numerical simulations of particle deposition in metal foam heat exchangers

Australia is a high-potential country for geothermal power with reserves currently estimated in the tens of millions of petajoules, enough to power the nation for at least 1000 years at current usage. However, these resources are mainly located in isolated arid regions where water is scarce. Therefore, wet cooling systems for geothermal plants in Australia are the least attractive solution and thus air-cooled heat exchangers are preferred. In order to increase the efficiency of such heat exchangers, metal foams have been used. One issue raised by this solution is the fouling caused by dust deposition. In this case, the heat transfer characteristics of the metal foam heat exchanger can dramatically deteriorate. Exploring the particle deposition property in the metal foam exchanger becomes crucial. This paper is a numerical investigation aimed to address this issue. Two dimensional (2D) numerical simulations of a standard one-row tube bundle wrapped with metal foam in cross-flow are performed and highlight preferential particle deposition areas.

Numerical simulations of particle deposition in metal foam heat exchangers

Australia is a high potential country for geothermal power with reserves currently estimated in the tens of millions of petajoules, enough to power the nation for at least 1000 years at current usage.However, these resources are mainly located in isolated arid regions where water is scarce. Therefore, wet cooling systems for geothermal plants in Australia are the least attractive solution and thus air-cooled heat exchangers are preferred. In order to increase the efficiency of such heat exchangers, metal foams have been used. One issue raised by this solution is the fouling caused by dust deposition. In this case, the heat transfer characteristics of the metal foam heat exchanger can dramatically deteriorate. Exploring the particle deposition property in the metal foam exchanger becomes crucial. This paper is a numerical investigation aimed to address this issue. Two-dimensional(2D numerical simulations of a standard one-row tube bundle wrapped with metal foam in cross-flow are performed and highlight preferential particle deposition areas.

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.

Cross-cultural web user interface design for Indigenous internet users

This project investigated 1) Australian web designers’ cultural perceptions towards Australian Indigenous users and 2) Australian Indigenous cultural features in terms of user interface design. In doing so, it reviews the literature of cross-cultural user interface design by focusing on feasible models and arguments to articulate and integrate Australian Indigenous Internet users’ cultural needs of web user interface. The online survey results collected from 101 Indigenous users and 126 Web designers showed a distinctive difference between them on the integration of Indigenous users' cultural in Web sites. The interview data collected from 14 Indigenous users and 14 web designers suggested practical approaches to the design implications of Indigenous culture.

Cross-layer design for traffic management in wireless networked control systems

Wireless networked control systems (WNCSs) have been increasingly deployed in industrial applications. As they require timely data packet transmissions, it is difficult to make efficient use of the limited channel resources, particularly in contention based wireless networks in the layered network architecture. Aiming to maintain the WNCSs under critical real-time traffic condition at which the WNCSs marginally meet the real-time requirements, a cross-layer design (CLD) approach is presented in this paper to adaptively adjust the control period to achieve improved channel utilization while still maintaining effective and timely packet transmissions. The effectiveness of the proposed approach is demonstrated through simulation studies.

‘I came to this country for a better life’ : factors mediating employment trajectories among young people who migrated to Australia as refugees during adolescence

Located at the intersection of two vulnerable groups in the contemporary labour market, young people who migrate as refugees during adolescence face a unique constellation of opportunities and challenges that shape their employment trajectories. Yet the tendency for research to focus on the early years of refugee settlement means that we have an inadequate understanding the factors that mediate their employment decisions, experiences and outcomes. Based on interviews with 51 young people, this article explores how aspirations, responsibilities, family, education and networks are understood to influence the employment trajectories of adolescent refugee migrants. While this article draws attention to the complex and dynamic range of challenges and constraints that these young people negotiate in the pursuit of satisfying and sustainable employment, what also emerges is an optimistic and determined cohort who, even as they at times unsuccessfully prepare for and navigate the labour market, maintain high hopes for a better life.

Modeling perceived influences on journalism : evidence from a cross-national survey of journalists

Surveying 1,700 journalists from seventeen countries, this study investigates perceived influences on news work. Analysis reveals a dimensional structure of six distinct domains—political, economic, organizational, professional, and procedural influences, as well as reference groups. Across countries, these six dimensions build up a hierarchical structure where organizational, professional, and procedural influences are perceived as more powerful limits to journalists' work than political and economic influences.

Does gender determine journalists' professional views? A reassessment based on cross-national evidence

Research into journalism and gender to date has found somewhat contradictory evidence as to the ways in which women and men practice journalism. While some scholars claim that women have inherently different concepts and practices of journalism and that this has led to a feminization of journalism, others have found little evidence to suggest that men and women differ significantly in terms of their role conceptions. While numerous studies have been conducted into this issue around the world, few have taken a truly comparative approach. This paper presents results from a large-scale comparative survey into gender differences in journalists’ professional views in 18 diverse countries around the world. Results suggest that women and men do not differ in any meaningful ways in their role conceptions on neither the individual level, in newsrooms dominated by women, nor in socio-cultural contexts where women have achieved a certain level of empowerment.

Born in another country : women's experience of labour and birth in Queensland, Australia

Background Women born outside Australia make up more than a fifth of the Queensland birthing population and like migrants in other parts of the world face the challenges of cultural dislocation and possible language barriers. Recognising that labour and birth are major life events the aim was to investigate the experiences of these women in comparison to native-born English speaking women. Methods Secondary analysis of data from a population based survey of women who had recently birthed in Queensland. Self-reported clinical outcomes and quality of interpersonal care of 481 women born outside Australia who spoke a language other than English at home were compared with those of 5569 Australian born women speaking only English. Results After adjustment for demographic factors and type of birthing facility, women born in another country were less likely to be induced, but more likely to have constant electronic fetal monitoring (EFM), to give birth lying on their back or side, and to have an episiotomy. Most women felt that they were treated as an individual and with kindness and respect. However, women born outside Australia were less likely to report being looked after ‘very well’ during labour and birth and to be more critical of some aspects of care. Conclusion In comparing the labour and birth experiences of women born outside the country who spoke another language with native-born English speaking women, the present study presents a largely positive picture. However, there were some marked differences in both clinical and interpersonal aspects of care.

HPAKE : Password authentication secure against cross-site user impersonation

We propose a new kind of asymmetric mutual authentication from passwords with stronger privacy against malicious servers, lest they be tempted to engage in “cross-site user impersonation” to each other. It enables a person to authenticate (with) arbitrarily many independent servers, over adversarial channels, using a memorable and reusable single short password. Beside the usual PAKE security guarantees, our framework goes to lengths to secure the password against brute-force cracking from privileged server information.

Who struggles most in making a career choice and why?Findings from a cross-sectional survey of highschool students

This paper reports findings from an empirical study examining the influence of student background and educational experiences on the development of career choice capability. Secondary school students attending years 9-12 (N = 706) in New South Wales (NSW), Australia, were invited to participate in an online survey that sought to examine factors influencing their career choices. The survey included questions relating to student demographics, parental occupation, attitudes to school and to learning, student aspirations, and students’ knowledge of the further education or skills required to achieve their desired goal. We found no significant differences in the proportions of students who were “uncertain” of their future career aspirations with respect to their socio-educational background. There were, however, significantly more students struggling with career decision making from an English-speaking background in comparison to households where children spoke a language other than English. Those students were proportionally present in government and non-government schools and had some behavioural and attitudinal characteristics in common.

Indigenous names for Indigenous Support Centres as part of the Welcome to (University) Country

The significance of naming Indigenous Support Centres (ISCs) with Indigenous language terminology — given that such reconciliatory acts may serve as symbolic means to improve the cultural efficacy of an Australian university’s Welcome to Country on offer to Indigenous Australian students — is explored and discussed in this paper. A survey of all 39 Australian universities was conducted, and the results regarding the Indigenous naming of their ISCs were tabulated and compared.

Winning the phishing war : a strategy for Australia

Phishing, a form of on-line identity theft, is a major problem worldwide, accounting for more than $7.5 Billion in losses in the US alone between 2005 and 2008. Australia was the first country to be targeted by Internet bank phishing in 2003 and continues to have a significant problem in this area. The major cyber crime groups responsible for phishing are based in Eastern Europe. They operate with a large degree of freedom due to the inherent difficulties in cross border law enforcement and the current situation in Eastern Europe, particularly in Russia and the Ukraine. They employ highly sophisticated and efficient technical tools to compromise victims and subvert bank authentication systems. However because it is difficult for them to repatriate the fraudulently obtained funds directly they employ Internet money mules in Australia to transfer the money via Western Union or Money gram. It is proposed a strategy, which firstly places more focus by Australian law enforcement upon transactions via Western Union and Money gram to detect this money laundering, would significantly impact the success of the Phishing attack model. This combined with a technical monitoring of Trojan technology and education of potential Internet money mules to avoid being duped would provide a winning strategy for the war on phishing for Australia.

Unusual cross-ring S(N)2 reactions of M-H (-) ions of methoxyacetanilides

Deprotonated o, m-, and p-methoxyacetanilide show pronounced peaks in their collision-induced tandem mass spectra (MS/MS) produced by losses of the elements of C2H6. It is proposed that this reaction is a 'cross-ring' internal S(N)2 reaction involving an incipient methyl anion. For example, p-CH3O-C6H4-N--CO-CH3--> [(p.CH3O-C6H4-N=C=O)CH3-]--> O---C6H4-N=C=O+C2H6.

Unusual cross-ring SN2 reactions of [MH]− ions of methoxyacetanilides

Deprotonated o, m-, and p-methoxyacetanilide show pronounced peaks in their collision-induced tandem mass spectra (MS/MS) produced by losses of the elements of C2H6. It is proposed that this reaction is a 'cross-ring' internal S(N)2 reaction involving an incipient methyl anion. For example, p-CH3O-C6H4-N--CO-CH3--> [(p.CH3O-C6H4-N=C=O)CH3-]--> O---C6H4-N=C=O+C2H6.