A review on reliability models with covariates

Modern Engineering Asset Management (EAM) requires the accurate assessment of current and the prediction of future asset health condition. Suitable mathematical models that are capable of predicting Time-to-Failure (TTF) and the probability of failure in future time are essential. In traditional reliability models, the lifetime of assets is estimated using failure time data. However, in most real-life situations and industry applications, the lifetime of assets is influenced by different risk factors, which are called covariates. The fundamental notion in reliability theory is the failure time of a system and its covariates. These covariates change stochastically and may influence and/or indicate the failure time. Research shows that many statistical models have been developed to estimate the hazard of assets or individuals with covariates. An extensive amount of literature on hazard models with covariates (also termed covariate models), including theory and practical applications, has emerged. This paper is a state-of-the-art review of the existing literature on these covariate models in both the reliability and biomedical fields. One of the major purposes of this expository paper is to synthesise these models from both industrial reliability and biomedical fields and then contextually group them into non-parametric and semi-parametric models. Comments on their merits and limitations are also presented. Another main purpose of this paper is to comprehensively review and summarise the current research on the development of the covariate models so as to facilitate the application of more covariate modelling techniques into prognostics and asset health management.

Modelling urban public transit users' route choice behaviour: review and outlook

This paper reviews the main development of approaches to modelling urban public transit users’ route choice behaviour from 1960s to the present. The approaches reviewed include the early heuristic studies on finding the least cost transit route and all-or-nothing transit assignment, the bus common line problem and corresponding network representation methods, the disaggregate discrete choice models which are based on random utility maximization assumptions, the deterministic use equilibrium and stochastic user equilibrium transit assignment models, and the recent dynamic transit assignment models using either frequency or schedule based network formulation. In addition to reviewing past outcomes, this paper also gives an outlook into the possible future directions of modelling transit users’ route choice behaviour. Based on the comparison with the development of models for motorists’ route choice and traffic assignment problems in an urban road area, this paper points out that it is rewarding for transit route choice research to draw inspiration from the intellectual outcomes out of the road area. Particularly, in light of the recent advancement of modelling motorists’ complex road route choice behaviour, this paper advocates that the modelling practice of transit users’ route choice should further explore the complexities of the problem.

How to progress forward in improving safety outcomes in the work-related driving field : a review of work-related driving research and development of an intervention framework [Extended abstract]

Road crashes are now the most common cause of work-related injury, death and absence in a number of countries. Given the impact of workrelated driving crashes on social and economic aspects of business and the community, workrelated road safety and risk management has received increasing attention in recent years. However, limited academic research has progressed on improving safety within the work-related driving sector. The aim of this paper is to present a review of work-related driving safety research to date, and provide an intervention framework for the future development and implementation of workrelated driving safety intervention strategies.

Open access policies, practices and licensing : a review of the literature in Australia and selected jurisdictions

The full economic, cultural and environmental value of information produced or funded by the public sector can be realised through enabling greater access to and reuse of the information. To do this effectively it is necessary to describe and implement a policy framework that supports greater access and reuse among a distributed, online network of information suppliers and users. The objective of this study was to identify materials dealing with policies, principles and practices relating to information access and reuse in Australia and in other key jurisdictions internationally. Open Access Policies, Practices and Licensing: A review of the literature in Australia and selected jurisdictions sets out the findings of an extensive review of published materials dealing with policies, practices and legal issues relating to information access and reuse, with a particular focus on materials generated, held or funded by public sector bodies. The report was produced as part of the work program of the project “Enabling Real-Time Information Access in Both Urban and Regional Areas”, established within the Cooperative Research Centre for Spatial Information (CRCSI).

Increasing socio-economic inequalities in drug-induced deaths in Australia : 1981-2002

Introduction and Aims: Since the 1990s illicit drug use death rates in Australia have increased markedly. There is a notable gap in knowledge about changing socio-economic inequalities in drug use death rates. Some limited Australian and overseas data point to higher rates of drug death in the lowest socio-economic groups, but the paucity of available studies and their sometimes conflicting findings need to be addressed. Design and Methods: This paper uses data obtained from the Australian Bureau of Statistics (ABS) to examine changes in age-standardised drug-induced mortality rates for Australian males over the period 1981 – 2002. Socio-economic status was categorised as manual or non-manual work status. Results: With the rapid increase in drug-induced mortality rates in the 1990s, there was a parallel increase in socio-economic inequalities in drug-induced deaths. The decline in drug death rates from 2000 onwards was associated with a decline in socio-economic inequalities. By 2002, manual workers had drug death rates well over twice the rate of non-manual workers. Discussion: Three factors are identified which contribute to these socio-economic inequalities in mortality. First, there has been an age shift in deaths evident only for manual workers. Secondly, there has been an increase in availability until 1999 and a relative decline in the cost of the drug, which most often leads to drug death (heroin). Thirdly, there has been a shift to amphetamine use which may lead to significant levels of morbidity, but few deaths. [Najman JM, Toloo G, Williams GM. Increasing socio-economic inequalities in drug-induced deaths in Australia: 1981–2002.

Debate on statutory control of the surveying profession in Queensland : 1907 to 1975

This article was written in 1997. After a 2009 review the content was left mostly unchanged - apart from this re-written abstract, restructured headings and a table of contents. The article deals directly with professional registration of surveyors; but it also relates to government procurement of professional services. The issues include public service and professional ethics; setting of professional fees; quality assurance; official corruption; and professional recruitment, education and training. Debate on the Land Surveyors Act 1908 (Qld) and its amendments to 1916 occurred at a time when industrial unrest of the 1890s and common market principles of the new Commonwealth were fresh in peoples’ minds. Industrial issues led to a constitutional crisis in the Queensland’s then bicameral legislature and frustrated a first attempt to pass a Surveyors Bill in 1907. The Bill was re-introduced in 1908 after fresh elections and Kidston’s return as state premier. Co-ordinated immigration and land settlement polices of the colonies were discontinued when the Commonwealth gained power over immigration in 1901. Concerns shifted to protecting jobs from foreign competition. Debate on 1974 amendments to the Act reflected concerns about skill shortages and professional accreditation. However, in times of economic downturn, a so-called ‘chronic shortage of surveyors’ could rapidly degenerate into oversupply and unemployment. Theorists championed a naïve ‘capture theory’ where the professions captured governments to create legislative barriers to entry to the professions. Supposedly, this allowed rent-seeking and monopoly profits through lack of competition. However, historical evidence suggests that governments have been capable of capturing and exploiting surveyors. More enlightened institutional arrangements are needed if the community is to receive benefits commensurate with sizable co-investments of public and private resources in developing human capital.

The measurement of broadband ultrasonic attenuation in cancellous bone-a review of the science and technology

The measurement of broadband ultrasonic attenuation (BUA) in cancellous bone at the calcaneus was first described in 1984. The assessment of osteoporosis by BUA has recently been recognized by Universities UK, within its EurekaUK book, as being one of the “100 discoveries and developments in UK Universities that have changed the world” over the past 50 years, covering the whole academic spectrum from the arts and humanities to science and technology. Indeed, BUA technique has been clinically validated and is utilized worldwide, with at least seven commercial systems providing calcaneal BUA measurement. However, a fundamental understanding of the dependence of BUA upon the material and structural properties of cancellous bone is still lacking. This review aims to provide a science- and technology-orientated perspective on the application of BUA to the medical disease of osteoporosis.

Difference-based meta-analytic procedures for between-participant and/or within-participant designs : a tutorial review for sports and exercise scientists

The aim of this paper is to provide a contemporary summary of statistical and non-statistical meta-analytic procedures that have relevance to the type of experimental designs often used by sport scientists when examining differences/change in dependent measure(s) as a result of one or more independent manipulation(s). Using worked examples from studies on observational learning in the motor behaviour literature, we adopt a random effects model and give a detailed explanation of the statistical procedures for the three types of raw score difference-based analyses applicable to between-participant, within-participant, and mixed-participant designs. Major merits and concerns associated with these quantitative procedures are identified and agreed methods are reported for minimizing biased outcomes, such as those for dealing with multiple dependent measures from single studies, design variation across studies, different metrics (i.e. raw scores and difference scores), and variations in sample size. To complement the worked examples, we summarize the general considerations required when conducting and reporting a meta-analysis, including how to deal with publication bias, what information to present regarding the primary studies, and approaches for dealing with outliers. By bringing together these statistical and non-statistical meta-analytic procedures, we provide the tools required to clarify understanding of key concepts and principles.

Predicting driver's hypovigilance on monotonous roads: literature review.

Drivers' ability to react to unpredictable events deteriorates when exposed to highly predictable and uneventful driving tasks. Particularly, highway design reduces the driving task mainly to a lane-keeping one. It contributes to hypovigilance and road crashes as drivers are often not aware that their driving behaviour is impaired. Monotony increases fatigue, however, the fatigue community has mainly focused on endogenous factors leading to fatigue such as sleep deprivation. This paper focuses on the exogenous factor monotony which contributes to hypovigilance. Objective measurements of the effects of monotonous driving conditions on the driver and the vehicle's dynamics is systematically reviewed with the aim of justifying the relevance of the need for a mathematical framework that could predict hypovigilance in real-time. Although electroencephalography (EEG) is one of the most reliable measures of vigilance, it is obtrusive. This suggests to predict from observable variables the time when the driver is hypovigilant. Outlined is a vision for future research in the modelling of driver vigilance decrement due to monotonous driving conditions. A mathematical model for predicting drivers’ hypovigilance using information like lane positioning, steering wheel movements and eye blinks is provided. Such a modelling of driver vigilance should enable the future development of an in-vehicle device that detects driver hypovigilance in advance, thus offering the potential to enhance road safety and prevent road crashes.

Measuring safety effectiveness : literature review

Cohen (1977) reviewed the then current research on occupational safety and stated that both strong company commitment to safety, and communication between all levels of a company are the most influential factors to improving safety. Other relevant factors included careful selection of staff, and early and continuous training throughout the lifetime with the company. These continue to be important factors in OHS today. There has been a continued decrease in the injury rates since Cohen’s review within the Australian construction industry, however, the construction industry has far more injuries and ill-health than the Australian average, with one fatality occurring on average per week in the Australian Construction Industry. The Fatality rate in the building and construction industry remains three times higher than the national average, and 15% of all industry fatalities are in the building and construction industry. In addition the construction industry pays one of the highest workers’ compensation premium rates – in 2001 alone approximately 0.5% ($267 million) of revenue would have to be allocated to the direct cost of 1998/99 compensations (Office of the Federal Safety Commissioner, 2006). Based on these statistics there is a need to measure and improve safety performance within the construction industry.

Evidence-based practice and information literacy

Evidence-based Practice (EBP) has recently emerged as a topic of discussion amongst professionals within the library and information services (LIS) industry. Simply stated, EBP is the process of using formal research skills and methods to assist in decision making and establishing best practice. The emerging interest in EBP within the library context serves to remind the library profession that research skills and methods can help ensure that the library industry remains current and relevant in changing times. The LIS sector faces ongoing challenges in terms of the expectation that financial and human resources will be managed efficiently, particularly if library budgets are reduced and accountability to the principal stakeholders is increased. Library managers are charged with the responsibility to deliver relevant and cost effective services, in an environment characterised by rapidly changing models of information provision, information access and user behaviours. Consequently they are called upon not only to justify the services they provide, or plan to introduce, but also to measure the effectiveness of these services and to evaluate the impact on the communities they serve. The imperative for innovation in and enhancements to library practice is accompanied by the need for a strong understanding of the processes of review, measurement, assessment and evaluation. In 2001 the Centre for Information Research was commissioned by the Chartered Institute of Library and Information Professionals (CILIP) in the UK to conduct an examination into the research landscape for library and information science. The examination concluded that research is “important for the LIS [library and information science] domain in a number of ways” (McNicol & Nankivell, 2001, p.77). At the professional level, research can inform practice, assist in the future planning of the profession, raise the profile of the discipline, and indeed the reputation and standing of the library and information service itself. At the personal level, research can “broaden horizons and offer individuals development opportunities” (McNicol & Nankivell, 2001, p.77). The study recommended that “research should be promoted as a valuable professional activity for practitioners to engage in” (McNicol & Nankivell, 2001, p.82). This chapter will consider the role of EBP within the library profession. A brief review of key literature in the area is provided. The review considers issues of definition and terminology, highlights the importance of research in professional practice and outlines the research approaches that underpin EBP. The chapter concludes with a consideration of the specific application of EBP within the dynamic and evolving field of information literacy (IL).

Listening, sharing understanding and facilitating consumer, family and community empowerment through a priority driven partnership in Far North Queensland

Objectives: This paper provides an example of a mental health research partnership underpinned by empowerment principles that seeks to foster strength among community organizations to support better outcomes for consumers, families and communities. It aims to raise awareness among researchers and service providers that empowerment approaches to assist communities to address mental health problems are not too difficult to be practical but require long-term commitment and appropriate support. Methods: A collaborative research strategy that has become known as the Priority Driven Research (PDR) Partnership emerged through literature review,consultations, Family Wellbeing Program delivery with community groups and activities in two discrete Indigenous communities. Progress to date on three of the four components of the strategy is described. Results: The following key needs were identified in a pilot study and are now being addressed in a research-based implementation phase: (i) gaining two-way understanding of perspectives on mental health and promoting universal awareness; (ii) supporting the empowerment of carers, families, consumers and at-risk groups through existing community organizations to gain greater understanding and control of their situation; (iii) developing pathways of care at the primary health centre level to enable support of social and emotional wellbeing as well as more integrated mental health care; (iv) accessing data to enable an ongoing process of analysis/sharing/planning and monitoring to inform future activity. Conclusion: One of the key learnings to emerge in this project so far is that empowerment through partnership becomes possible when there is a concerted effort to strengthen grassroots community organizations. These include social health teams and men’s and women’s groups that can engage local people in an action orientation. Key words: Aboriginal, empowerment, Indigenous, mental health.

Incomplete pregnancy and risk of ovarian cancer : results from two Australian case-control studies and systematic review

Although full-term pregnancies reduce the risk of ovarian cancer, it has not been conclusively established whether incomplete pregnancies also influence risk. We investigated the relationship between a history of incomplete pregnancy and incident epithelial ovarian cancer among over 4,500 women who participated in two large Australian population-based case-control studies in 1990-1993 and 2002-2005. They provided responses to detailed questions about their reproductive histories and other personal factors. Summary odds ratios (OR) and confidence intervals (CI) derived from each study using the same covariates were aggregated. We found no significant associations between the number of incomplete pregnancies and ovarian cancer, for parous (OR = 0.98, 95% CI: 0.89, 1.08) or nulliparous (OR = 1.06, 95% CI: 0.75, 1.48) women, nor for the number of spontaneous or induced abortions and ovarian cancer for parous women (OR = 0.95, 95% CI 0.82, 1.09; OR = 1.08, 95% CI: 0.86, 1.36) or nulliparous women (OR = 1.2, 95% CI: 0.6, 2.4; OR = 0.8, 95% CI: 0.47, 1.38), respectively. A systematic review of 37 previous studies of the topic confirmed our findings that a history of incomplete pregnancy does not influence a woman’s risk of epithelial ovarian cancer.