59 resultados para Crash cushions.


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Objectives To establish the association between the patient's perception of fault for the crash and 12-month outcomes after non-fatal road traffic injury.Setting Two adult major trauma centres, one regional trauma centre and one metropolitan trauma centre in Victoria, Australia.Participants 2605 adult, orthopaedic trauma patients covered by the state's no-fault third party insurer for road traffic injury, injured between September 2010 and February 2014.Outcome measures EQ-5D-3L, return to work and functional recovery (Glasgow Outcome Scale—Extended score of upper good recovery) at 12 months postinjury.Results After adjusting for key confounders, the adjusted relative risk (ARR) of a functional recovery (0.57, 95% CI 0.46 to 0.69) and return to work (0.92, 95% CI 0.86 to 0.99) were lower for the not at fault compared to the at fault group. The ARR of reporting problems on EQ-5D items was 1.20–1.35 times higher in the not at fault group. Conclusions Patients who were not at fault, or denied being at fault despite a police report of fault, experienced poorer outcomes than the at fault group. Attributing fault to others was associated with poorer outcomes. Interventions to improve coping, or to resolve negative feelings from the crash, could facilitate better outcomes in the future.

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It is known that tailoring a hot stamping part, to achieve locally graded properties, can improve the crash behavior. Depending on the role of the structural part (carrying either bending or axial crash load), the best position for the local regions with lower strength and higher ductility can be different. The distribution of these local regions and their mechanical properties affects the crash behavior of the part in each loading case and therefore can be effectively designed to improve the crash performance. To investigate these effects and examine the improvement possibilities, a numerical thermalmechanical-metallurgical model of a hot stamping process and a representative side impact crash model were created and analysed. The hot stamping model was used to predict the consequent phase fractions and mechanical properties of tailored hot stamping parts produced with different tailoring scenarios. In the metallurgical model, a modified phase transformation model based on Scheil’s additive principle was incorporated. The geometry and mesh of the stamped part was exported to a crash numerical model with a 3-point bending configuration. A constitutive model was used to define the plastic behavior of the stamped part corresponding to different hardness values. Various possibilities in locally positioning the high strength or high ductility zones of material were examined. The results show that the positioning of the soft zones has a more significant effect on the crash performance than the variation in their mechanical properties of these soft zones.

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The stock market crash of 1987 had a profound effect on corporate Australia and the Australian community in general. The fall-out revealed that some of our most respected business figures had not been as ethical, or even as lawful, as we would have hoped. This impropriety produced in Australia an awakening to business ethics. Whilst many companies endeavoured to introduce ethical practices into their corporations, they perceived ethics as a way of minimising damage to the corporation and in some cases as a means of competitive advantage. What was lost was the reason that one should embark on business ethics; and that is to make the society and corporate Australia a more ethical place in which to exist.This paper proposes a model based on 2 factors: commitment and partnerships, as a means of enabling corporate Australia to refocus attention on the main purpose of being inherently ethical in all that we do. This ethical model requires a commitment to partnerships with all stakeholders both internal and external in an attempt to enhance the level of ethical business practices that are contemplated and pursued within corporate Australia. Whilst the research agenda and the information collected is Australian-based, it is hoped that the ideas contained within this paper will have a wider appeal to corporations in similar cultural settings.

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The stock market crash of 1987 was a defining moment in Australian corporate life. As a nation, we became acutely aware of the ‘moral bankruptcy’ that had come to permeate our corporate world. The focus on business ethics or the lack of it, in corporate Australia in the late 1980s, prompted this research.

The research for this paper that was first conducted in 1995 and replicated in 2001 focussed on the top 500 companies in Australia. These companies were surveyed on a raft of issues, one of which was their use of their codes of ethics in the marketplace. This paper examines the data sets from 1995 and 2001 and concludes that many of Australia’s largest enterprises have recognised the need for business ethics. As perceived by them, they can and do use their codes of ethics in a positive manner in the marketplace and attribute benefits to this interaction.

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Increased fuel economy, combined with the need for the improved safety has generated the development of new hot-rolled high-strength low-alloy (HSLA) and multiphase steels such as dual-phase or transformation-induced plasticity steels with improved ductility without sacrificing strength and crash resistance. However, the modern multiphase steels with good strength-ductility balance showed deteriorated stretch-flangeability due to the stress concentration region between the soft ferrite and hard martensite phases [1]. Ferritic, hot-rolled steels can provide good local elongation and, in turn, good stretch-flangeability [2]. However, conventional HSLA ferritic steels only have a tensile strength of not, vert, similar600 MPa, while steels for the automotive industry are now required to have a high tensile strength of not, vert, similar780 MPa, with excellent elongation and stretch-flangeability [1]. This level of strength and stretch-flangeability can only be achieved by precipitation hardening of the ferrite matrix with very fine precipitates and by ferrite grain refinement. It has been suggested that Mo [3] and Ti [4] should be added to form carbides and decrease the coiling temperature to 650 °C since only a low precipitation temperature can provide the precipitation refinement [4]. These particles appeared to be (Ti, Mo)C, with a cubic lattice and a parameter of 0.433 nm, and they were aligned in rows [4]. It was reported [4] that the formation of these very fine carbides led to an increase in strength of not, vert, similar300 MPa. However, the detailed analysis of these particles has not been performed to date due to their nanoscale size. The aim of this work was to carry out a detailed investigation using atom probe tomography (APT) of precipitates formed in hot-rolled low-carbon steel containing additions Ti and Mo.

The investigated low-carbon steel, containing Fe–0.1C–1.24Mn–0.03Si–0.11Cr–0.11Mo–0.09Ti–0.091Al at.%, was produced by hot rolling. The processing route has been described in detail elsewhere [5] European Patent Application, 1616970 A1, 18.01.2006.[5]. The microstructure was characterised by transmission electron microscopy (TEM) on a Philips CM 20, operated at 200 kV using thin foil and carbon replica techniques. Qualitative energy dispersive X-ray spectroscopy (EDXS) was used to analyse the chemical composition of particles. The atomic level of particle characterisation was performed at the University of Sydney using a local electrode atom probe [6]. APT was carried out using a pulse repetition rate of 200 kHz and a 20% pulse fraction on the sample with temperature of 80 K. The extent of solute-enriched regions (radius of gyration) and the local solute concentrations in these regions were estimated using the maximum separation envelope method with a grid spacing of 0.1 nm [7]. A maximum separation distance between the atoms of interest of dmax = 1 nm was used.

The microstructure of the steel consisted of two types of fine ferrite grains: (i) small recrystallised grains with an average grain size of 1.4 ± 0.2 μm; and (ii) grains with a high dislocation density (5.8 ± 1.4 × 1014 m−2) and an average grain size of 1.9 ± 0.1 μm in thickness and 2.7 ± 0.1 μm in length (Fig. 1a). Some grains with high dislocation density displayed an elongated shape with Widmanstätten side plates and also the formation of cells and subgrains (Fig. 1a). The volume fraction of recrystallised grains was 34 ± 8%.


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As a result of recent increases in fuel prices and the growing number of accident fatalities, the two major concerns of the automotive industry and their customers are now occupant safety and fuel economy {1, 2]. Increasing the amount of energy and optimizing the manner in which energy is absorbed within vehicle crush zones can improve occupant survivability in the event of a crash, while fuel economy is improved through a reduction in weight.  Axial crush tests were conducted on tubular specimens of Carbon/Epoxy (Toray T700/G83C) and Glass/Polypropylene (Twintex). This paper presents results from the tests conducted at quasi-static rates at Deakin Unniversity, Victoria Australia, and intermediate rate tests performed at the Oak Ridge National Laboratory, Tennessee  USA.   The quasi-static tests were conducted at 10mm/min (1.67x10-4m/s) using 5 different forms of initiation. Tests at intermediate rates were performed at speeds of 0.25m/s, 0.5m/s, 0.75m/s 1m/s, 2m/s and 4m/s. Quasi-static tests of tubular specimens showed high specific energy absorption (SEA) values with 86 kJ/kg for Carbon/Epoxy specimens. The SEA of the Glass/Polypropylene specimens was measured to be 29 kJ/kg. Results from the intermediate test rates showed that SEA values did not fall below 55kJ/kg for carbon specimens or 35kJ/kg for the Glass/Polypropylene specimens. When compared with typical steel and aluminium, SEA values of 15 kJ/kg and 30kJ/kg respectively, the benefits of using composite materials in crash structures is apparent.                                                                     

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Accurate finite element crash simulations of side impact depend upon a thorough understanding of dynamic tube bending. There is a need to understand the dynamic bending mode of square sections (equivalent of automotive structural parts) to obtain a greater confidence in CAE. This work varied strain rate and material definitions, such as Cowper-Symonds vs Zerilli-Armstrong, as well as initial velocity and yield strength. The results show that most of the plastic work is done between strains rates of 30 ¿ 300/s and strains up to 0.3. Peak strain rates were marginally above 1000/s with maximum strain greater than 1. When the strain rate definition and material model were modified, it was shown that a higher yield stress produced a higher reaction force. These results would suggest that the strain rate sensitivity needs to be carefully identified for accurate crash simulations.

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Background: Motorcycle crash victims form a high proportion of those killed or injured in road traffic accidents. Injuries to the head, following motorcycle crashes, are a common cause of severe morbidity and mortality. It seems intuitive that helmets should protect against head injuries but it has been argued that motorcycle helmet use decreases rider vision and increases neck injuries. This review will collate the 'current available evidence on helmets and their impact on mortality, and head, face and neck injuries following motorcycle crashes.

Objectives: To quantify the effectiveness of wearing a motorcycle helmet in reducing mortality and head and neck injury following motorcycle crashes.

Search strategy: Databases including the Cochrane Injuries Group Specialised Register, Cochrane Central Register of Controlled Trials (The Cochrane Library issue 1,2003), MEDLINE (January 1966 to February 2003), EMBASE (January 1985 to February 2003), CINAHL (January 1982 to February 2003), IRRD (International Road Research Documentation), TRANSDOC, TRIS (Transport Research Information Service), ATRI (Australian Transport Index) (1976 to Feb 2003), Science Citation Index were searched for relevant articles. Web sites of traffic and road accident research bodies including government agencies were also searched. Reference lists from topic reviews, identified studies and bibliographies were examined for relevant articles.

Selection criteria: We considered for inclusion studies that investigated a population of motorcycle riders who had crashed, examining helmet use as an intervention and with outcomes that included one or more of the following: death, head, neck or facial injury. Studies included any that compared an intervention and control group and, therefore, included any randomised controlled trials, non-randomised controlled trials, cohort, case-control and cross-sectional studies. Ecological and case series studies were excluded.

Data collection and analysis: Two reviewers independently screened reference lists for eligible articles. Two reviewers independently assessed articles for inclusion criteria. Data were abstracted by two independent reviewers using a standard abstraction form.

Main results: Fifty-three observational studies were identified of varying quality. Despite methodological differences there was a remarkable consistency in results, particularly for mortality and head injury outcomes. Motorcycle helmets appear to reduce the risk of mortality although, due to heterogeneity in study design, an overall estimate of effect was not calculated. There was some evidence that the effect of helmets on mortality is modified by speed. Motorcycle helmets were found to reduce the risk of head injury and from five well-conducted studies the risk reduction is estimated to be 72% (OR 0.28, 95%CI 0.23,0.35). Insufficient evidence was found to estimate the effect of motorcycle helmets compared with no helmet on facial or neck injuries. However, studies of poorer quality suggest that helmets have no effect on the risk of neck injuries and are protective for facial injury. There was insufficient evidence to demonstrate whether differences in helmet type confer more or less advantage in injury reduction.

Conclusions:
Motorcycle helmets reduce the risk of mortality and head injury in motorcycle riders who crash, although the former effect may be modified by other crash factors such as speed. Further well-conducted research is required to determine the effects of helmets and different helmet types on mortalIty, head, neck and facial injuries. However, the findings suggest that global efforts to reduce road traffic injuries may be facilitated by increasing helmet use by motorcyclists.

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Business ethics is a subject that recently has been thrust again into prominence in industrialised economies around the world, due to the revelations of the practices of some of the major corporations operating within the USA. In Australia, corporate collapses such as HIH and Onetel and in Sweden, the scandals with the top executives of Skandia and also Systembolaget have brought in to sharp focus that these practices are not confined to the USA. Since the early 1960s, codes of ethics have been in evidence in many organisations in the USA, whilst in Australia, as in Britain, the interest in codes of ethics was piqued by the stock market crash of 1987. In Sweden, however, this concept of the use of codes of ethics in the corporate sector had not been investigated prior to this study. This paper examines the use of codes of ethics in the marketplace by the top companies operating in corporate Australia and corporate Sweden. The outcome of this research shows that in both Australia and Sweden that large organisations indicate a substantial interest in codes of ethics and value the use of their codes in the marketplace. There are, however, differences in the ways that the companies in each country implement their codes of ethics in the marketplace and the benefits that they see as being derived from them.

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A novel method of composite tube manufacture was developed for potential use in automotive crash structures. Tubes were crushed axially under quasi-static conditions and highly repeatable behaviour was observed with an average specific energy absorption of -85kJ/kg. DMTA results indicated that the tubes were fully cured, even when the cycle was reduced to 7 minutes, giving this process huge potential for high-volume production.

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Over the last decade, there has been a growing interest in examining health expenditures. In this paper, we study the behaviour of health expenditures in the G3 countries (USA, the UK, and Japan) and three European countries (the UK, Switzerland and Spain) over the period 1960–2000 from a different perspective, in that we examine: (1) whether there is a common structural break in health expenditures across the G3 and European countries; (2) whether structural breaks have slowed down health expenditure growth rates in these countries or vice versa. Our main findings are that: (1) health expenditures share a common break in both bivariate and trivariate cases, and structural breaks and break intervals suggest that either one or a combination of events (second oil price shock, the 1987 stock market crash and/or recessions) have contributed to the commonality of break in health expenditures in the G3, while the oil price shocks have been instrumental in the commonality of breaks for the European countries; (2) except for the UK, structural breaks have slowed down growth rates in health expenditures for the USA, Japan, Switzerland and Spain.

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A common characteristic among parallel/distributed programming languages is that the one language is used to specify not only the overall organisation of the distributed application, but also the functionality of the application. That is, the connectivity and functionality of processes are specified within a single program. Connectivity and functionality are independent aspects of a distributed application. This thesis shows that these two aspects can be specified separately, therefore allowing application designers to freely concentrate on either aspect in a modular fashion. Two new programming languages have been developed for specifying each aspect. These languages are for loosely coupled distributed applications based on message passing, and have been designed to simplify distributed programming by completely removing all low level interprocess communication. A suite of languages and tools has been designed and developed. It includes the two new languages, parsers, a compilation system to generate intermediate C code that is compiled to binary object modules, a run-time system to create, manage and terminate several distributed applications, and a shell to communicate with the run-tune system. DAL (Distributed Application Language) and DAPL (Distributed Application Process Language) are the new programming languages for the specification and development of process oriented, asynchronous message passing, distributed applications. These two languages have been designed and developed as part of this doctorate in order to specify such distributed applications that execute on a cluster of computers. Both languages are used to specify orthogonal components of an application, on the one hand the organisation of processes that constitute an application, and on the other the interface and functionality of each process. Consequently, these components can be created in a modular fashion, individually and concurrently. The DAL language is used to specify not only the connectivity of all processes within an application, but also a cluster of computers for which the application executes. Furthermore, sub-clusters can be specified for individual processes of an application to constrain a process to a particular group of computers. The second language, DAPL, is used to specify the interface, functionality and data structures of application processes. In addition to these languages, a DAL parser, a DAPL parser, and a compilation system have been designed and developed (in this project). This compilation system takes DAL and DAPL programs to generate object modules based on machine code, one module for each application process. These object modules are used by the Distributed Application System (DAS) to instantiate and manage distributed applications. The DAS system is another new component of this project. The purpose of the DAS system is to create, manage, and terminate many distributed applications of similar and different configurations. The creation procedure incorporates the automatic allocation of processes to remote machines. Application management includes several operations such as deletion, addition, replacement, and movement of processes, and also detection and reaction to faults such as a processor crash. A DAS operator communicates with the DAS system via a textual shell called DASH (Distributed Application SHell). This suite of languages and tools allowed distributed applications of varying connectivity and functionality to be specified quickly and simply at a high level of abstraction. DAL and DAPL programs of several processes may require a few dozen lines to specify as compared to several hundred lines of equivalent C code that is generated by the compilation system. Furthermore, the DAL and DAPL compilation system is successful at generating binary object modules, and the DAS system succeeds in instantiating and managing several distributed applications on a cluster.

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Metallic tubes have been extensively studied for their crashworthiness as they closely resemble automotive crash rails. Recently, the demand to produce light weight yet safer vehicles has led to the need to understand the behaviour of novel materials such as composites, metallic foams and sandwich structures durign a crash. This paper presents a method to predict the crashworthiness of structural components using material modes. The material factors that most affect the crushing response are determined and quantified by developing and validating the crushing of a square tube model in Abaqus. The inputs from the model are used to construct a simple, physically realistic constitutive model and new test methods for predicting the material behaviour at high strain rates using low test speeds. These material models enable a designer to predict the crash behaviour of a structure without the need to perform extensive physical tests, thus reducing the time and cost of development.

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Prior research by Bouman and Jacobsen (2002) document unusually high monthly returns over the period November-April for both United States (U.S.) and foreign stock markets and label this phenomenon the Halloween effect. The implication is that the Halloween effect represents an exploitable anomaly, which has negative implications for stock market efficiency. We extend this research to the S&P 500 futures contract and find no evidence of an exploitable Halloween effect over the period April 1982 through April 2003. Re-examining Bouman and Jacobsen’s empirical results for the U.S., we find that two outliers drive their results. These two outliers are associated with the “Crash” in October 1987 and collapse of the hedge fund Long-Term Capital Management in August 1998. After inserting a dummy variable to account for the impact of the two identified outliers, the Halloween effect disappears.