Failure of discontinuous railhead edges due to plastic strain accumulation

Railhead is perhaps the highest stressed civil infrastructure due to the passage of heavily loaded wheels through a very small contact patch. The stresses at the contact patch cause yielding of the railhead material and wear. Many theories exist for the prediction of these mechanisms of continuous rails; this process in the discontinuous rails is relatively sparingly researched. Discontinuous railhead edges fail due to accumulating excessive plastic strains. Significant safety concern is widely reported as these edges form part of Insulated Rail Joints (IRJs) in the signalling track circuitry. Since Hertzian contact is not valid at a discontinuous edge, 3D finite element (3DFE) models of wheel contact at a railhead edge have been used in this research. Elastic–plastic material properties of the head hardened rail steel have been experimentally determined through uniaxial monotonic tension tests and incorporated into a FE model of a cylindrical specimen subject to cyclic tension load- ing. The parameters required for the Chaboche kinematic hardening model have been determined from the stabilised hysteresis loops of the cyclic load simulation and imple- mented into the 3DFE model. The 3DFE predictions of the plastic strain accumulation in the vicinity of the wheel contact at discontinuous railhead edges are shown to be affected by the contact due to passage of wheels rather than the magnitude of the loads the wheels carry. Therefore to eliminate this failure mechanism, modification to the contact patch is essential; reduction in wheel load cannot solve this problem.

Solicitors who commence a proceeding without authority act at their peril

In Nominal Defendant v Kisse [2001] QDC 290 a person suffered personal injury caused by a motor vehicle in circumstances where there was a cause of action to which the Motor Accident Insurance Act 1994 applied. The person died before taking the steps required under Pt 4 of the Act and before commencing litigation to enforce that cause of action. The decision also involved a costs order against solicitors on an indemnity basis, providing a timely reminder to practitioners of the importance of ensuring they have proper authority before commencing any court proceedings.

A survey in mathematics for industry: Two-timing and matched asymptotic expansions for singular perturbation problems

Following the derivation of amplitude equations through a new two-time-scale method [O'Malley, R. E., Jr. & Kirkinis, E (2010) A combined renormalization group-multiple scale method for singularly perturbed problems. Stud. Appl. Math. 124, 383-410], we show that a multi-scale method may often be preferable for solving singularly perturbed problems than the method of matched asymptotic expansions. We illustrate this approach with 10 singularly perturbed ordinary and partial differential equations. © 2011 Cambridge University Press.

A Combined Renormalization Group-Multiple Scale Method for Singularly Perturbed Problems

This paper introduces a straightforward method to asymptotically solve a variety of initial and boundary value problems for singularly perturbed ordinary differential equations whose solution structure can be anticipated. The approach is simpler than conventional methods, including those based on asymptotic matching or on eliminating secular terms. © 2010 by the Massachusetts Institute of Technology.

Control social y familia en el siglo XIX colombiano : una aproximación a distintas prácticas de regulación estatal

This article explores a number of social control strategies on individuals and families actioned by the newly created state-national project during the first decades of Colombian XIX century. With special attention on the discourse of urbanity, also named 'civility or good manners', this paper analyses literary sources produced in the time for molding citizens behaviors in order to incorporate the society into the new paradigm of Modernity.

A promise and a possibility : the limitations of the traditional criminal justice system as an explanation for the emergence of restorative justice

The claim that restorative justice emerged in response to the failings of the traditional criminal justice system is frequently made and rarely challenged in the restorative justice literature. It is stated unproblematically, as though it is an unassailable fact rather than a powerful truth claim, thereby positioning restorative justice as a natural, progressive and superior model of justice in comparison with the traditional criminal justice system. This truth claim therefore bestows restorative justice with a legitimacy that is difficult to challenge or refute. Drawing on a Foucaultian genealogy of restorative justice, this article seeks to destabilise the truth claim that restorative justice emerged in response to the failings of the criminal justice system. While the shortcomings of the traditional criminal justice system may provide a backdrop to the emergence of restorative justice, this article argues that such a possibility makes restorative justice a possibility rather than an inevitability.

The Habitual Rhythms of Becoming-Involved: Insights into Participation Experiences in Urban Spaces by Children with Diverse Mobility

This chapter reports on a study that reveals the essence of participation in urban spaces by ten children who live with various physical conditions: Muscular Dystrophy, Cerebral Palsy, and Autoimmune Rheumatic Diseases. These conditions affect muscle and movement differently resulting in diverse ways in which children move through space (personal mobility). The children at the time of the research were 9-12 years of age residing in South-east Queensland, Australia. The approach and methods selected for this study, interpretive phenomenological inquiry and grounded theory, were chosen for their capacity to capture the complexity and multiple interactions of the child’s urban living. The confronting and poignant accounts by children and their families of their experiences produced a new way of understanding the concept of participation, as a ‘journey of becoming involved.’ Their accounts of performing everyday routines (e.g. leaving home, getting in and out of the car, and entering places) in urban spaces (neighbourhood streets, schools, open spaces, shopping centres, and hospitals) revealed differences in the way settings were experienced. These differences were associated with the interplay between the body, space and context. Where interplays were problematic, explicit decisions about children’s involvement were made. These decisions were described in terms of ‘avoid going’, ‘pick and choose’, ‘discontinue’, ‘accept’, or ‘contest.’ What these decisions mean is some spaces are avoided, some journeys are discontinued, and some barriers encountered in journeys are normalised as everyday experiences, i.e. ‘tolerable discrimination’. These actions resulted in experiences of non-participation or partial–tokenistic participation. The key substantive contribution of the research lies in the identification of points in children’s journeys that shape participation experience. These points identify where future interventions in policy, programming and design can be made to make real and sustaining changes to lives of children and their families in geographies crucial to urban living.

In for the long haul : family business succession at HaulageCo

This is a case about family business succession. Because many successions fail, the 'problem of succession' is a key issue in the family business field (see Aronoff 1998; Bird eta/. 2002; Dyer & Sanchez 1998; Sharma 2004; Zalu·a & Sharma 2004). Indeed, from the non-family business literature, we know one third of relay successions - like this case where there is an identified successor - will fail, with the prospective CEO leaving before succeeding the incumbent CEO (Cmmella & Shen 2001). Research on next generation family business members is limited. Successor ath·ibutes (Chrisman, Chua & Sharma 1998; Sharma & Rao 2000), as well as various characteristics such as socialisation (Garcia-Aivmez, L6pez-Sintas & Gonzalvo 2002) a11d gender (Haberman & Danes 2007; Vera & Dean 2005) have all been considered to play a role. So too have successor intentions (Stavrou & Swiercz 1998), motivation (Le Breton-Miller, Miller & Steier 2004), commitment (Sharma & Irving 2005) and transformation from follower to leadership (Cater & Justis 2009). In this case, by outlining the socialisation of the successors, explanations of their motivations for joining a11d their current employment we can begin to see some of the underlying mechanisms at work motivating the next generation to join and stay in the family business.

Too cool for homeschool? Accessing underground unschoolers with Web 2.0

There is a new type of home education parent challenging long-held assumptions about homeschooling (cf. Morton 2012). These parents are well educated (cf. Beck 2010) but have chosen to eschew the social and cultural capital (Bourdieu & Wacquant 1992) of school in favour of some- thing completely different. They are unschoolers, which involves ‘allow- ing children as much freedom to learn in the world as their parents can possibly bear’ (cf. Holt & Farenga 2003: 238). This chapter presents the approach taken by one researcher to explore the reasons families choose unschooling. These families can be difficult to access, because they often fail to register with home education units and thus remain outside the education system (cf. Townsend 2012). Their lack of registration makes them largely invisible, affecting their ability to make an important contribution to debates around education. In spite of this invisibility, many unschoolers are keen to talk to researchers to increase wider understanding of unschooling.

Biological monitoring and Biological Limit Values (BLV): the strategy of the European Union

Occupational standards concerning allowable concentrations of chemical compounds in the ambient air of workplaces have been established in several countries worldwide. With the integration of the European Union (EU), there has been a need of establishing harmonised Occupational Exposure Limits (OEL). The European Commission Directive 95/320/EC of 12 July 1995 has given the tasks to a Scientific Committee for Occupational Exposure Limits (SCOEL) to propose, based on scientific data and where appropriate, occupational limit values which may include the 8-h time-weighted average (TWA), short-term limits/excursion limits (STEL) and Biological Limit Values (BLVs). In 2000, the European Union issued a list of 62 chemical substances with Occupational Exposure Limits. Of these, 25 substances received a "skin" notation, indicating that toxicologically significant amounts may be taken up via the skin. For such substances, monitoring of concentrations in ambient air may not be sufficient, and biological monitoring strategies appear of potential importance in the medical surveillance of exposed workers. Recent progress has been made with respect to formulation of a strategy related to health-based BLVs.

Hydrolysis of genotoxic methyl-substituted oxiranes : Experimental kinetic and semiempirical studies

The kinetics of acid-catalyzed hydrolysis of seven methylated aliphatic epoxides - R1R2C(O)CR3R4 (A: R1=R2=R3=R4=H; B: R1=R2=R3=H, R4=Me; C: R1=R2=H, R3=R4=Me; D: R1=R3=H, R2=R4=Me(trans); E: R1=R3=H, R2=R4=Me(cis); F: R1=R3=R4=Me, R2=H; G: R1=R2=R3=R4=Me) - has been studied at 36 ± 1.5°C. Compounds with two methyl groups at the same carbon atom of the oxirane ring exhibit highest rate constants (k(eff) in reciprocal molar concentration per second: 11.0 ± 1.3 for C, 10.7 ± 2.1 for F, and 8.7 ± 0.7 for G as opposed to 0.124 ± 0.003 for B, 0.305 ± 0.003 for D, and 0.635 ± 0.036 for E). Ethylene oxide (A) displays the lowest rate of hydrolysis (0.027 M-1 s-1). The results are consistent with literature data available for compounds A, B, and C. To model the reactivities we have employed quantum chemical calculations (MNDO, AM1, PM3, and MINDO/3) of the main reaction species. There is a correlation of the logarithm k(eff) with the total energy of epoxide ring opening. The best correlation coefficients (r) were obtained using the AM1 and MNDO methods (0.966 and 0.957, respectively). However, unlike MNDO, AM1 predicts approximately zero energy barriers for the oxirane ring opening of compounds B, C, E and G, which is not consistent with published kinetic data. Thus, the MNDO method provides a preferential means of modeling the acidic hydrolysis of the series of methylated oxiranes. The general ranking of mutagenicity in vitro, A > B > C, is in line with the concept that this sequence also gradually leaves the expoxide reactivity optimal for genotoxicity toward reactivities leading to higher biological detoxifications.

Effectiveness of a puppet show on iodine knowledge, attitudes and behaviour of elementary students and the indirect effects on their parents and households in Ho Chi Minh City : a pilot study

Deficiencies in iodine levels have been shown to seriously affect a child’s intellectual development and learning capacity.1 In South-East Asia, iodine deficiency remains a major public health concern. Approximately 30% of the region’s population of 503.6 million have insufficient iodine intake, and only 61% of households have access to iodized salt.1 For this reason, it is necessary to initiate effective, community-based health promotion activities that are targeted toward populations of various ages. A puppet show is one imaginative and entertaining method of health education that has been advocated for use in communicating positive health behaviours to children.2e5 The authors undertook a literature review and found no studies assessing the effectiveness of a puppet show to teach an iodine education programme...

Overview of New Work Health and Safety Laws

This definitive guide (formerly the Australian Master OHS & Environment Guide) is a first point of reference for work health and safety best practice and strategy. Written by WHS and legal experts, the guide provides key information on the challenges that professionals and organisations face in relation to WHS. It includes valuable information on legal obligations and risk management, and covers the latest changes brought about by the Work Health and Safety Act.