http://hdl.handle.net/2440/17679 Mon, 20 May 2013 12:22:12 GMT 2013-05-20T12:22:12Z http://hdl.handle.net/2440/77812 Title: Use of a damped Hertz contact model to represent head impact safety tests Author: Searson, Daniel Jeffrey; Anderson, Robert William Gerard; Hutchinson, Timothy Paul Abstract: Head impacts tests are conducted as part of many types of safety testing, with applications including vehicle crashes, helmets and sports surfaces. A common measure of head injury in these tests is the Head Injury Criterion (HIC), which is calculated from the measured acceleration of a headform during the impact. In this paper, these headform impacts are represented by a Hertz contact model to which a damping term has been added. A power law relationship was found to be appropriate for modelling the effect of headform mass and impact speed on HIC and peak displacement. It was found that the stiffness and damping in the model did not affect the exponents in the power law, but the exponent of displacement in the contact model did have an effect on all of the exponents in the power law. This result may explain why some variation exists in real data. The relationships presented in this paper may be used to predict how the HIC and maximum displacement of the head will vary for a given change in head mass or impact speed. This has applications in test protocol development and for evaluating the safety performance of tested structures under a variety of real world conditions. Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/77812 2011-12-31T13:30:00Z http://hdl.handle.net/2440/77811 Title: Testing in order to measure the protection against impact of people, manufactured items, and agricultural produce: How to consider all severities of shock Author: Hutchinson, Timothy Paul; Anderson, Robert William Gerard; Searson, Daniel Jeffrey Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/77811 2011-12-31T13:30:00Z http://hdl.handle.net/2440/77444 Title: In vivo biomechanical response of ovine heads to shaken baby syndrome events Author: Sandoz, Baptiste; Dutschke, Jeffrey Kym; Liu, Q.; Manavis, Jim; Finnie, John Walker; Vink, Robert; Anderson, Robert William Gerard Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/77444 2011-12-31T13:30:00Z http://hdl.handle.net/2440/77179 Title: Risky behaviours: preferable to crashes for evaluating road safety mass media campaigns? Author: Wundersitz, Lisa Narelle; Hutchinson, Timothy Paul Abstract: Decades of research have failed to establish whether or not mass media advertising can reduce road crashes. The probable reason is that the random variability in crash numbers is too great (and, campaigns being very cheap per person reached, even low effectiveness may be enough to be worthwhile). Three alternatives to before-after comparison of crashes as the method of determining effectiveness of an intervention are discussed. These are real-world experiments of high methodological quality, laboratory experiments of the social psychological type, and the measurement of safety-related behaviors. The third of these, before-after comparison of behaviors or variables that can be objectively observed and are closely linked to safety, is suggested as the most promising. However, the behaviors that might plausibly be used as proxies for crashes are quite few in number, and there is an urgent research need to find more of them, together with theory implying that a change in the behavior does indeed mean a change in safety. Sat, 31 Dec 2011 13:30:00 GMT http://hdl.handle.net/2440/77179 2011-12-31T13:30:00Z