723 research outputs found

    How do kinship (family and friends) foster carers experience their role and working relationships within the children’s workforce? (Sharing our experience, Practitioner-led research 2008-2009; PLR0809/054)

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    This research was undertaken in a London local authority and consisted of semi-structured interviews with five kinship foster carers approved by the local authority. The research used a qualitative approach consisting of one-off, face to face interviews with the aim of finding out how kinship foster carers experience their role and working relationships within the children’s workforce. Kinship foster carers are family and friends who look after children and young people in public care, on behalf of the local authority and within the terms of the Children Act 1989. A semi-structured interview schedule was devised to address the areas of interest, with a series of open questions and prompts. The interviews, with the participant’s permission, were digitally recorded alongside contemporaneous notes being made, and were subsequently written up to produce the dataset for the analysis. The main findings from the research include: • The carers in this study were very positive about the support they received from their supervising social workers, but were critical of the fact that children were often not provided with a consistent social worker. • Some carers in this study were dissatisfied with the level of financial remuneration. • In terms of the working relationship with education and health professionals, all participants reported positive experiences, but while this study sought to see how kinship carers were viewed as part of the children’s workforce, the carers themselves wanted to be viewed as ‘family’ and not professionals. • In relation to the possibility that relative and non-relative kinship carers experienced their role differently, there is no evidence from this brief study to suggest that this may be the case. Both relative and nonrelative carers demonstrate a warmth and commitment to ‘their’ children, reinforcing the importance of kinship care as a preferred placement option for many children

    A comparison of the results from intra-pleural and intra-peritoneal studies with those from inhalation and intratracheal tests for the assessment of pulmonary responses to inhalable dusts and fibres.

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    The aim of this paper is to compare results from inhalation studies with those from intraperitoneal and intrapleural tests, where available, for a number of fibrous and particulate test materials. The objective is to determine how well intraperitoneal/intrapleural studies predict the pathological responses observed in more standard in vivo studies of pulmonary toxicity, with a particular focus on carcinogenicity. Published toxicity data was obtained for a number of materials including asbestos, wollastonite, MMVFs (including glass fibres, stone wools and RCF), silicon carbide whiskers, potassium octatitanate, quartz, kevlar, polypropylene and titanium dioxide. For some of the fibrous material reviewed, there is conformity between the results of intraperitoneal and inhalation tests such that they are either consistently positive or consistently negative. For the remaining fibrous materials reviewed, intraperitoneal and inhalation tests give different results, with positive results in the intraperitoneal test not being reflected by positive inhalation results. It is suggested that the intraperitoneal test can be used to exonerate a dust or fibre (because if negative in the intraperitoneal test it is extremely unlikely to be positive in either inhalation or intratracheal tests) but should not be used to positively determine that a dust or fibre is carcinogenic by inhalation. We would argue against the use of intraperitoneal tests for human health risk assessment except perhaps for the purpose of exoneration of a material from classification as a carcinogen.Peer reviewedFinal Accepted Versio

    The Influence of Route Characteristics, Train Design and Maintenance Policy on Wheel Tread Damage, Wheel Life and Costs for Multiple-Unit Trains

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    In the UK, the use of similar vehicle types by a range of privatised operators gives the opportunity to assess the influence of different route conditions and maintenance practices on wheel tread damage, wheelset life and costs. This paper investigates these influences, using data obtained directly from the train operators and maintainers. By disseminating best practice it is expected that wheelset life can be improved on many fleets, with resultant cost savings

    Development of a vehicle dynamics controller for obstacle avoidance

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    As roads become busier and automotive technology improves, there is considerable potential for driver assistance systems to improve the safety of road users. Longitudinal collision warning and collision avoidance systems are starting to appear on production cars to assist drivers when required to stop in an emergency. Many luxury cars are also equipped with stability augmentation systems that prevent the car from spinning out of control during aggressive lateral manoeuvres. Combining these concepts, there is a natural progression to systems that could assist in aiding or performing lateral collision avoidance manoeuvres. A successful automatic lateral collision avoidance system would require convergent development of many fields of technology, from sensors and instrumentation to aid environmental awareness through to improvements in driver vehicle interfaces so that a degree of control can be smoothly and safely transferred between the driver and vehicle computer. A fundamental requirement of any collision avoidance system is determination of a feasible path that avoids obstacles and a means of causing the vehicle to follow that trajectory. This research focuses on feasible trajectory generation and development of an automatic obstacle avoidance controller that integrates steering and braking action. A controller is developed to cause a specially modified car (a Mercedes `S' class with steer-by-wire and brake-by-wire capability) to perform an ISO 3888-2 emergency obstacle avoidance manoeuvre. A nonlinear two-track vehicle model is developed and used to derive optimal controller parameters using a series of simulations. Feedforward and feedback control is used to track a feasible reference trajectory. The feedforward control loops use inverse models of the vehicle dynamics. The feedback control loops are implemented as linear proportional controllers with a force allocation matrix used to apportion braking effort between redundant actuators. Two trajectory generation routines are developed: a geometric method, for steering a vehicle at its physical limits; and an optimal method, which integrates steering and braking action to make full use of available traction. The optimal trajectory is obtained using a multi-stage convex optimisation procedure. The overall controller performance is validated by simulation using a complex proprietary model of the vehicle that is reported to have been validated and calibrated against experimental data over several years of use in an industrial environment

    Residual Stress in Wheels: Comparison of Neutron Diffraction and Ultrasonic Methods, with Trends in RCF

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    The critical damage mechanism on many GB passenger train wheels is Rolling Contact Fatigue (RCF) cracking in the rim. Evidence from field observations suggests that RCF damage occurs much more quickly as the wheelsets near the end of their life. Wheel manufacturing processes induce a compressive hoop stress in the wheel rim; variations in residual stress through the life of a wheel may influence the observed RCF damage rates. This paper describes experiments to measure residual stresses in new and used wheel rims to identify whether this could be a significant factor, and compares the findings from neutron diffraction and ultrasonic birefringence methods. The scope goes beyond previous applications of neutron diffraction to railway wheels and identifies key considerations for future testing. Assuming that the as-manufactured stress distribution was similar for all three wheels tested, it is found that the stresses are redistributed within the wheel rim during its life as material is removed and plastic flow occurs. However, the hoop stress near the running surface remains compressive and may not have a large influence on the RCF damage rates

    Some economic consequences of the transition from civil war to peace

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    Drawing on evidence from Africa - especially Ethiopia and Uganda - the authors of this volume draw conclusions about economic policy in the aftermath of civil war. A sample of conclusions follows. Civil wars differ from international wars. They are informal, often have no clear beginning and end, weaken rather than strengthen the authority of the state, and leave two unreconciled armies to be demobilized within one territory. Civil wars erode the institutions of civil society, leading to a decline in the stock of social capital, which takes some time to restore. Private investment and government revenue are slow to recover, and military expenditures are not easily reduced. As a result, there is little or no peace dividend in the short run. The period of transition to peace is a particularly suitable time for radical policy reform, despite the high degree of polarization typical in countries engaged in civil war. And speedy reform, far from increasing uncertainty, is likely to reduce it. After a civil war, private agents are fearful both of each other and of the government. This, perhaps even more than physical damage to infrastructure, hinders private-sector-led recovery, as irreversible investment is delayed despite being financeable. The transition to peace is primarily the transition from fear and the defensive responses that became ingrained in wartime. The peace dividend comes as a gradual recovery of confidence induces repatriation of financial and human capital. Such confidence can be boosted by the early sequencing of investment-sensitive policy reforms and by preserving low inflation through direct consumer price index targeting. Lack of confidence can be compensated for by temporary undervaluation of the exchange rate, or however, may prove more difficult to make credibly time-bound. Finally, aid can permit accelerated rehabilitation of the infrastructure (especially transport networks) needed to return to a market economy. Contrary to the studies hypothesis, the authors found that demobilization - at least in Uganda - did not lead to a significant upsurge in insecurity. In the short term, demobilization significantly reduced crime, unless the demobilized lacked access to land. If the demobilized returned to their home areas and were given some assistance, with identifiable exceptions they were able to find income-earning opportunities.Debt Markets,Emerging Markets,Economic Theory&Research,,Investment and Investment Climate

    Research and calibration of Acoustic Sensors in ice within the SPATS (South Pole Acoustic Test Setup) project

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    We present development work aiming towards a large scale ice-based hybrid detector including acoustic sensors for the detection of neutrinos in the GZK range. A facility for characterization and calibration of acoustic sensors in clear (bubble-free) ice has been developed and the first measurements done at this facility are presented. Further, a resonant sensor intended primarily for characterization of the ambient noise in the ice at the South Pole has been developed and some data from its performance are given.Comment: 4 pages, 8 figures, ARENA 2010 conference proceeding

    Optimisation of Wheelset Maintenance: Current Research Activities

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    Recent research projects relating to wheelset damage and maintenance practices includes: - Influence of changes in material properties on observed damage - Optimisation of wheelset maintenance to reduce whole-system costs - Investigating the influence of route and vehicle design and maintenance policy on wheel tread damage - Assessment of alternative wheel profiles, considering both whole-system costs and running safety - Categorisation of wheel damage mechanisms to improve identification and selection of appropriate mitigation This presentation provides an overview of some of these research area

    Nonlinear model predictive motion control of linear motor drive for micro/nano-positioning applications

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