An examination of the relationship between cycle training,cycle accidents,attitudes and cycling behaviour among children

Around 40% of 10-11-year-old children receive cycle training every year in the UK, but concern has been expressed over the efficacy of training courses. One argument is that accidents occur too infrequently to be a viable evaluative criterion, and attitudes and behaviour have been suggested as alternatives. A questionnaire that measured a number of variables including accidents, attitudes, and behaviour was completed by 336 participants from two schools in the London Borough of Bromley. At least one cycling injury had been sustained by 58.3% of respondents, requiring hospital treatment in 19.1% of cases. Girls reported fewer accidents than boys. No relationship between training and accidents was found. A principal components analysis (PCA) of the attitudes items produced a 'safe attitudes' factor. Girls displayed 'safer' attitudes, but there was no evidence that training produced safer attitudes. A PCA of the cycling behaviour scales produced two factors, 'safe cycling' and 'showing off'. Safe cyclists who obeyed basic safety rules were less likely to sustain cycle injuries, but showing off was not related to accidents. Girls were less likely to show off, but the safe behaviour gender difference did not reach significance. Training did not relate to either factor.     

The effects of axial tension on the hogging-moment regions of composite beams

Structural parts commonly comprised of composite members such as bridge approaches, inclined parking ramps and stadium beams, can be subjected to a combination of high axial loads and bending moments. Steel-concrete composite construction is a popular solution for these types of structures due to the numerous advantages that they offer. Although, current design codes (e.g. Eurocode 4, American code AISC, Australian codes AS2327 and AS5100) provide rules for the design of composite columns subjected to flexure and axial load, however the design of composite beams, which are asymmetric in nature under the combined effects of tension and bending, is not yet fully addressed. This paper investigates the ultimate strength of composite beams under the combined effects of axial tension and negative (hogging) bending moment. An experimental programme carried out in the laboratory of the University of Western Sydney comprised of a total of six specimens representing composite beams and subjected to various levels of axial tension and bending moment. Ultimate failure modes were identified and the resulting interaction diagrams were compared to the results of sectional rigid plastic analysis. Following the tests, three-dimensional finite element models were employed using the ABAQUS finite element software to further investigate the nonlinear behaviour of the composite beams and extend the experimental observations by studying the effects of parameters such as the span length and the effect of partial shear connection. Finally, simple design rules and formulae are proposed for use in engineering practice.     

真空灭弧室 配电开关 断路器和接触器的高可靠性元件

自从20世纪50年代中期将真空灭弧室(VI)用作配电操作开关、断路器和接触器的电流分断元件以来,其作用逐步增强.在电路的开断和配电保护领域,该电气产品已经占统治地位.真空灭弧室甚至被引入到电力输送中的通断产品的领域上.真空灭弧室受到追捧的原因有:结构紧凑、适用范围广、成本低、极好的电寿命和机械寿命,以及使用方便.其中,最重要的优点是公认的高可靠性.     

Current status and opportunities in chalcopyrite solar cells

The chalcopyrite semiconductors, and most commonly Cu(In,Ga)Se₂, are the active layers in the highest-efficiency thin film photovoltaics, both in small cells and modules. The modules show excellent stability and can be produced by a wide range of techniques. The manufacturing community is scaling up their facilities with the potential to produce large areas at competitive costs in the near future. The devices can be produced without toxic constituents and by non-vacuum processes. Ultimately the materials could yield very high efficiency multijunction devices in thin film one-sun modules with levellized costs of energy competitive with any current technology.     

Fast 3D thermal simulation of power module packaging

This paper presents a thermal model that uses a Fourier series solution to the heat equation to carry out transient 3D thermal simulation of power device packaging. The development and implementation of this physics‐based method is described. The method is demonstrated on a stacked 3D multichip module. The required aspects of 3D heat conduction are captured successfully by the model. Compared with previous thermal models presented in literature, it is fast, accurate and can be easily integrated with an inverter circuit simulator to model realistic converter load cycles. Copyright © 2012 John Wiley & Sons, Ltd.     

Sputter deposition of ferroelectric thin films

Ferroelectric films are typically deposited by a variety of techniques, the two most common being chemical methods (sol-gel, metalorganic decomposition) and sputtering. In this paper we briefly review the sputtering techniques, and then discuss ion beam sputter deposition in greater detail. In particular, ion beam sputter deposition of epitaxial lead zirconate titanate (PZT) films is described. It is shown that the films with compositions close to the morphotropic boundary typically show well-developed ferroelectric hysteresis loops, Pmax around 45 μC/cm2, and Pr around 20 μC/cm2. In comparison with typical polycrystalline sol-gel PZT films, however, coercive fields of thin epitaxial films are large (120-200 kV/cm for 95 nm films). The pulsed fatigue behavior is remarkably similar to a polycrystalline non-oriented sol-gel PZT film investigated for comparison. The similarities suggest that the aging behavior may be dominated by the electrodes, which were Pt in both systems.     

The Imperial College Thermophysical Properties Data Centre

The IUPAC Thermodynamic Tables Project Centre in London has at its disposal considerable expertise on the production and utilization of high-accuracy equations of state which represent the thermodynamic properties of substances. For some years they have been content to propagate this information by the traditional method of book production, but the increasing use of the computer in industry for process design has shown that an additional method was needed. The setting up of the IUPAC Transport Properties Project Centre, also at Imperial College, whose products would also be in demand by industry, afforded the occasion for a new look at the problem. The solution has been to set up the Imperial College Thermophysical Properties Data Centre, which embraces the two IUPAC Project Centres, and for it to establish a link with the existing Physical Properties Data Service of the Institution of Chemical Engineers, thus providing for the dissemination of the available information without involving the Centres in problems such as those of marketing and advertising. This paper outlines the activities of the Centres and discusses the problems in bringing their products to the attention of industry in suitable form.Paper presented at the Ninth Symposium on Thermophysical Properties, June 24–27, 1985, Boulder, Colorado, U.S.A.     

Evidence for terror management theory II: The effects of mortality salience on reactions to those who threaten or bolster the cultural worldview.

Three experiments were conducted to test the hypothesis, derived from terror management theory, that reminding people of their mortality increases attraction to those who consensually validate their beliefs and decreases attraction to those who threaten their beliefs. In Study 1, subjects with a Christian religious background were asked to form impressions of Christian and Jewish target persons. Before doing so, mortality was made salient to half of the subjects. In support of predictions, mortality salience led to more positive evaluations of the in-group member (the Christian) and more negative evaluations of the out-group member (the Jew). In Study 2, mortality salience led to especially negative evaluations of an attitudinally dissimilar other, but only among subjects high in authoritarianism. In Study 3, mortality salience led to especially positive reactions to someone who directly praised subjects' cultural worldviews and especially negative reactions to someone who criticized them. The implications of these findings for understanding in-group favoritism, prejudice, and intolerance of deviance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)