Design and test of a custom instrumented leg press for injury and recovery intervention

There is an increasing desire and emphasis to integrate assessment tools into the everyday training environment of athletes. These tools are intended to fine-tune athlete development, enhance performance and aid in the development of individualised programmes for athletes. The areas of workload monitoring, skill development and injury assessment are expected to benefit from such tools. This paper describes the development of an instrumented leg press and its application to testing leg dominance with a cohort of athletes. The developed instrumented leg press is a 45° reclining sled-type leg press with dual force plates, a displacement sensor and a CCD camera. A custom software client was developed using C#. The software client enabled near-real-time display of forces beneath each limb together with displacement of the quad track roller system and video feedback of the exercise. In recording mode, the collection of athlete particulars is prompted at the start of the exercise, and pre-set thresholds are used subsequently to separate the data into epochs from each exercise repetition. The leg press was evaluated in a controlled study of a cohort of physically active adults who performed a series of leg press exercises. The leg press exercises were undertaken at a set cadence with nominal applied loads of 50%, 100% and 150% of body weight without feedback. A significant asymmetry in loading of the limbs was observed in healthy adults during both the eccentric and concentric phases of the leg press exercise (P < .05). Mean forces were significantly higher beneath the non-dominant limb (4–10%) and during the concentric phase of the muscle action (5%). Given that symmetrical loading is often emphasized during strength training and remains a common goal in sports rehabilitation, these findings highlight the clinical potential for this instrumented leg press system to monitor symmetry in lower-limb loading during progressive strength training and sports rehabilitation protocols.

Occupational Health and Safety, Courts and Crime: the legal construction of occupational health and safety offences in Victoria

This book reports on an empirically-based study of the manner in which the Magistrates' Courts in Victoria, construct occupational health and safety (OHS) issues when hearing prosecutions for offences under the Victorian OHS legislation. Prosecution has always been a controversial element in the enforcement armoury of OHS regulators, but at the same time it has long been argued that the low level of fines imposed by courts has had an important chilling effect on the OHS inspectorate's enforcement approaches, and on the impact of OHS legislation. Using a range of empirical research methods, including three samples of OHS prosecutions carried out in the Victorian Magistrates' Courts, Professor Johnstone shows how courts, inspectors, prosecutors and defence counsel are involved in filtering or reshaping OHS issues during the prosecution process, both pre-trial and in court. He argues that OHS offences are constructed by focusing on "events", in most cases incidents resulting in injury or death. This "event-focus" ensures that the attention of the parties is drawn to the details of the incident, and away from the broader context of the event. During the court-based sentencing process defence counsel is able to adopt a range of techniques which isolate the incident from its micro and macro contexts, thereby individualising and decontextualising the incident.

The court and the factory the legal construction of occupational health and safety offences in Victoria

This thesis reports on an empirically based study of the manner in which Victorian Magistrates Courts constructed occupational health and safety (OHS) issues when hearing prosecutions for offences under the Industrial Safety, Health and Welfare Act 1981 (the ISHWA) and the Occupational Health and Safety Act 1985 (OHSA) from 1983 to 1991. These statutes established OHS standards for employers and other relevant parties. The State government enforced these standards through an OHS inspectorate which had a range of enforcement powers, including prosecution. After outlining the historical development of Victoria’s OHS legislation, the magistracy’s historical role in its enforcement, and the development of an enforcement culture in which inspectors viewed prosecution as a last resort, the study shows how the key provisions of the ISHWA and OHSA required occupiers of workplaces and employers to provide and maintain safe systems of work, including the guarding of dangerous machinery. Using a wide range of empirical research methods and legal materials, it shows how the enforcement policies, procedures and practices of the inspectorate heavily slanted inspectors workplace investigations and hence prosecutions towards a restricted and often superficial, analysis of incidents (or “events”) most of which involved injuries on machinery. There was evidence, however, that after the establishment of the Central Investigation Unit in 1989 cases were more thoroughly investigated and prosecuted. From 1990 the majority of prosecutions were taken under the employer’s general duty provisions, and by 1991 there was evidence that prosecutions were focusing on matters other than machinery guarding.

A critical review of structural equation modeling applications in construction research

Structural equation modeling (SEM) is a versatile multivariate statistical technique, and applications have been increasing since its introduction in the 1980s. This paper provides a critical review of 84 articles involving the use of SEM to address construction related problems over the period 1998–2012 including, but not limited to, seven top construction research journals. After conducting a yearly publication trend analysis, it is found that SEM applications have been accelerating over time. However, there are inconsistencies in the various recorded applications and several recurring problems exist. The important issues that need to be considered are examined in research design, model development and model evaluation and are discussed in detail with reference to current applications. A particularly important issue concerns the construct validity. Relevant topics for efficient research design also include longitudinal or cross-sectional studies, mediation and moderation effects, sample size issues and software selection. A guideline framework is provided to help future researchers in construction SEM applications.

Practices and effectiveness of building information modelling in construction projects in China

Based on an investigation of 106 projects involving the use of building information modelling (BIM), this paper examines current BIM practices in China, and assesses how various practices alter their effectiveness. The results reveal that in current practice BIM is principally employed as a visualization tool, and how it is implemented is significantly associated with project characteristics. BIM use in the majority of the surveyed projects is seen to have positive outcomes, with the benefits of improved task effectiveness being more substantial than those related to efficiency improvement. The results also provide evidence that project characteristics significantly influence the success of BIM use; however, more substantial contributing factors to BIM effectiveness are the extent of integrated use and client/owner support. While indicating that current BIM practices involve both technological and organizational problems, the findings also provide insights into how the potential for BIM could be better exploited within the industry.

A new ambiguity acceptance test threshold determination method with controllable failure rate

The ambiguity acceptance test is an important quality control procedure in high precision GNSS data processing. Although the ambiguity acceptance test methods have been extensively investigated, its threshold determine method is still not well understood. Currently, the threshold is determined with the empirical approach or the fixed failure rate (FF-) approach. The empirical approach is simple but lacking in theoretical basis, while the FF-approach is theoretical rigorous but computationally demanding. Hence, the key of the threshold determination problem is how to efficiently determine the threshold in a reasonable way. In this study, a new threshold determination method named threshold function method is proposed to reduce the complexity of the FF-approach. The threshold function method simplifies the FF-approach by a modeling procedure and an approximation procedure. The modeling procedure uses a rational function model to describe the relationship between the FF-difference test threshold and the integer least-squares (ILS) success rate. The approximation procedure replaces the ILS success rate with the easy-to-calculate integer bootstrapping (IB) success rate. Corresponding modeling error and approximation error are analysed with simulation data to avoid nuisance biases and unrealistic stochastic model impact. The results indicate the proposed method can greatly simplify the FF-approach without introducing significant modeling error. The threshold function method makes the fixed failure rate threshold determination method feasible for real-time applications.

Across the divide - Criminology as other: Observations on the construction of the field

In 1978 Donald Cressey commented on an emerging division in the study of crime with some scholars concentrating on the development of a “crime fi ghting coalition” and others concerned with the processes associated with “making laws, breaking laws, and the reaction to the breaking of laws” (1978: 175). Since Cressey’s paper, many others have refl ected on the distinction between criminology and the sociology of crime and deviance (Akers, 1992; Garland, 1999; Garland & Sparks, 2000; Konty, 2007). But does such a distinction actually exist? Adopting a pragmatic position, the immediate answer is yes, if we assume that these categories have substance on the basis that they are grounded in everyday beliefs, institutional preferences and research practice (Konty, 2007). Moreover, these are viable categories in that some people studying crime label themselves criminologists (or are given this label by others) while others prefer or are given the label sociologist. Of course, there are further labels that may apply to persons studying crime, which include psychologist, penologist, biologist, chemist, and so on. One could argue that such labels are unimportant, however, it remains that these categories have a practical character. For criminology and the sociology of crime in particular, scholarly discourse frames these categories as oppositional (Bader et al., 1996.; Bendle, 1989; Laub & Sampson, 1991; Sibley, 2002) and to the extent that this has occurred, the categories have social relevance.

Use of contract models to improve environmental outcomes in transport infrastructure construction

The type of contract model may have a significant influence on achieving project objectives, including environmental and climate change goals. This research investigates non-standard contract models impacting greenhouse gas emissions (GHG) in transport infrastructure construction in Australia. The research is based on the analysis of two case studies: an Early Contractor Involvement (ECI) contract and a Design and Construct (D&C) contract with GHG reduction requirements embedded in the contractor selection. Main findings support the use of ECIs for better integrating decisions made during the planning phase with the construction activities, and improve environmental outcomes while achieving financial and time savings. Key words: greenhouse gases reduction; road construction; contracting; ECI; D&C

Analyzing causes for reworks in construction projects in China

Although rework is a common phenomenon in the Chinese construction industry and significantly affects project success, the reasons for rework remain largely unknown and most construction companies are unable to manage the issue effectively. To investigate the causes of rework in construction projects, a total of 39 causes were first identified through a comprehensive literature review and semi-structured interviews with 13 experienced construction professionals in China. A questionnaire survey was further conducted to prioritize these causes, in which unclear project process management, poor quality of construction technology, and the use of poor construction materials rank the highest. Finally, a factor analysis revealed 11 major underlying dimensions of these causes, relating to design management, communication management, field management, project scope management, project process management, active rework, project plan changes, subcontractor management, contract management, owner capability, and the external environment. The contribution of this work lies in its examination of the underlying causes of rework perceived by construction professionals in the world’s largest developing country, which is characterized by its unique economic and social systems. In particular, newly identified causes of contract management, active rework, and scope management help expand existing knowledge of the underlying causes of rework for the global construction community.

Toward a model for forming psychological safety climate in construction project management

The nature of construction projects and their delivery exposes participants to accidents and dangers. Safety climate serves as a frame of reference for employees to make sense of safety measures in the workplace and adapt their behaviors. Though safety climate research abounds, fewer efforts are made to investigate the formation of a safety climate. An effort to explore forming psychological safety climate, an operationalization of safety climate at the individual level, is an appropriate starting point. Taking the view that projects are social processes, this paper develops a conceptual framework of forming the psychological safety climate, and provides a preliminary validation. The model suggests that management can create the desired psychological safety climate by efforts from structural, perceptual, interactive, and cultural perspectives. Future empirical research can be built on the model to provide a more comprehensive and coherent picture of the determinants of safety climate.

Transformerless PV inverters - recent test results and a discussion of DC current injection and safety issues

With the variety of PV inverter types and the number of transformerless PV inverters on the Australian market increasing, we revisit some of the issues associated with these topologies. A recent electric shock incident in Queensland (luckily without serious outcome) associated with a transformerless PV system, highlights the need for earthing PV array structures and PV module frames to prevent capacitive leakage currents causing electric shock. The presented test results of the relevant voltages associated with leakage currents of five transformerless PV inverters stress this requirement, which is currently being addressed by both the Clean Energy Council and Standards Australia. DC current injection tests were performed on the same five inverters and were used to develop preliminary recommendations for a more meaningful DC current test procedure for AS4777 Part 2. The test circuit, methodology and results are presented and discussed. A notable temperature dependency of DC current injections with three of the five inverters suggests that DC current injection should be tested at high and low internal inverter temperatures whereas the power dependency noted only for one inverter does not seem to justify recommendations for a (rather involved) standard test procedure at different power levels.

A model to estimate the durability performance of both normal and light-weight concrete

There has been an increasing focus on the development of test methods to evaluate the durability performance of concrete. This paper contributes to this focus by presenting a study that evaluates the effect of water accessible porosity and oven-dry unit weight on the resistance of both normal and light-weight concrete to chloride-ion penetration. Based on the experimental results and regression analyses, empirical models are established to correlate the total charge passed and the chloride migration coefficient with the basic properties of concrete such as water accessible porosity, oven dry unit weight, and compressive strength. These equations can be broadly applied to both normal and lightweight aggregate concretes. The model was also validated by an independent set of experimental results from two different concrete mixtures. The model provides a very good estimate on the concrete’s durability performance in respect to the resistance to chloride ion penetration.

Improving safety communication of ethnic minorities in the construction industry of Hong Kong

The construction workforce in Hong Kong is experiencing a severe ageing problem and labour shortage. One initiative to enhance the supply of manpower is to assist ethnic minorities joining the industry. It is foreseeable that the percentage of ethnic minorities in the construction workforce will keep increasing. Statistics show that ethnic minorities were nearly 30% more likely to have work-related injuries than local workers in some developed countries. However, official statistics on the safety of ethnic minorities are not available in Hong Kong. A search in newspaper archive revealed that ethnic minorities in the construction industry of Hong Kong are subjected to higher fatality rate than local workers, just as is the case in many developed countries. This reflects that the safety of ethnic minorities has not received the attention it rightly deserves. Safety communication has been one of the key factors leading to accidents. Safety communication barriers of ethnic minorities impede them from receiving safety training and acquiring safety information effectively. Research towards improving the safety communication of ethnic minorities in the construction industry of Hong Kong becomes more urgent. This paper will provides an initial report on a research project which focuses on improving the safety communication of ethnic minorities in the construction industry of Hong Kong. Quantitative and qualitative research methods including Social Network Analysis (SNA) applied in conducting the research are first discussed. Preliminary statistics of construction accidents related to ethnic minorities in Hong Kong are then presented.

Examining the implementation of ISO 9001 in Indonesian construction companies

Purpose To examine the implementation of quality management systems (QMSs) of Grade 7 (G-7) Indonesian construction companies. This includes the initial motives that have driven the development of QMSs, barriers to effective QMS implementation, the current practice and integration of QMS-ISO 9001 principles and elements, and the performance of contractors implementing such QMSs. Design/methodology/approach A survey was conducted involving 403 respondents (Quality Management Representatives, Managers, and Project and Site Engineers) from 77 G-7 as well as ISO 9001 certified Indonesian construction companies. Findings The main motive for G-7 contractors in establishing and implementing ISO 9001 based QMSs are identified as being to effectively and efficiently control project activities. Respondents apparently do not often experience problems related to QMS implementation. However, issues of management attitude and purpose are identified as barriers that may affect effective QMS implementation. The study highlights the ISO 9001 principles and elements that still require to be more critically applied by G-7 contractors in order to fully implement and improve their current QMS effectiveness. The findings also suggest that, although certified, many G-7 contractors have not yet achieved a satisfactory level of performance to be truly competitive in global markets outside Indonesia. Originality/value To date, only limited research has been conducted into the application of ISO 9001 in the Indonesian construction industry. The research findings reinforced the value of pursuing more effective QMS implementation. They also support current attempts to introduce ISO 9001 QMSs to a much wider base of Indonesian construction companies, particularly small and medium sized contractors and builders.