Batting with occluded vision: An in situ examination of the information pick-up and interceptive skills of high- and low-skilled cricket batsmen

The capability of cricket batsmen of different skill levels to pick-up information from the pre-release movement pattern of the bowler, from pre-bounce ball flight, and from post-bounce ball flight was examined experimentally. Six highly skilled and six low-skilled cricket batsmen batted against three different leg-spin bowlers while wearing liquid crystal spectacles. The spectacles permitted the specific information available to the batsmen on each trial to be manipulated such that vision was either: (i) occluded at a point prior to the point of ball release (thereby only allowing vision of advance information from the bowler's delivery action); (ii) occluded at a point prior to the point of bat[ bounce (thereby permitting the additional vision of pre-bounce ball flight); or (iii) not occluded (thereby permitting the additional vision of post-bounce bat[ flight information). Measurement was made on each trial of both the accuracy of the definitive (forward-backward) foot movements made by the batsmen and their success (or otherwise) in making bat-bat[ contact. The analyses revealed a superior capability of the more skilled players to make use of earlier (pre-bounce) bat[ flight information to guide successful bat-bat[ interception, thus mirroring the greater use of prospective information pick-up by skilled performers observed in other aspects of batting and in other time-constrained performance domains. (c) 2006 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

Alloying of pure magnesium with Mg-33.3 wt-%Zr master alloy

To capitalise on the strengthening potential of zirconium as a potent grain refiner for magnesium alloys, the mechanisms of adding zirconium to magnesium and its subsequent grain refining action need to be understood. Using a Mg-33.3Zr master alloy (Zirmax supplied by Magnesium Elektron Ltd) as a zirconium alloying additive, the influence of different alloying conditions on the dissolution of zirconium in magnesium was investigated. It was found that owing to the highly alloyable microstructure of Zirmax, the dissolution of zirconium was generally complete within a few minutes in the temperature range 730 to 780degreesC. Prolonging and/or intensifying stirring were found to have no conspicuous influence on further enhancing the dissolution of zirconium. In all cases studied, the average grain size increased with increasing holding time at temperature while the total zirconium content decreased. The finest grain structure and highest total zirconium content corresponded to sampling immediately after stirring. Pick up of iron by molten magnesium from the mild steel crucibles used for melting and holding, was significantly delayed or avoided in the temperature range 730 to 780degreesC by coating the crucibles with boron nitride. It is therefore feasible to conduct zirconium alloying at 730degreesC without the need of a considerable excess of Zirmax addition using a properly coated or lined steel crucible.

Probing expert anticipation with the temporal occlusion paradigm: Experimental investigations of some methodological issues

Two experiments were conducted to examine whether the conclusions drawn regarding the timing of anticipatory information pick-up from temporal occlusion studies are influenced by whether (a) the viewing period is of variable or fixed duration and (b) the task is a laboratory-based one with simple responses or a natural one requiring a coupled, interceptive movement response. Skilled and novice tennis players either made pencil-and-paper predictions of service direction (Experiment 1) or attempted to hit return strokes (Experiment 2) to tennis serves while their vision was temporally occluded in either a traditional progressive mode (where more information was revealed in each subsequent occlusion condition) or a moving window mode (where the visual display was only available for a fixed duration with this window shifted to different phases of the service action). Conclusions regarding the timing of information pick-up were generally consistent across display mode and across task setting lending support to the veracity and generalisability of findings regarding perceptual expertise in existing laboratory-based progressive temporal occlusion studies.

How do world-class cricket batsmen anticipate a bowler's intention?

Four experiments are reported that examine the ability of cricket batsmen of different skill levels to pick up advance information to anticipate the type and length of balls bowled by swing and spin bowlers. The information available upon which to make the predictive judgements was manipulated through a combination of temporal occlusion of the display and selective occlusion or presentation of putative anticipatory cues. In addition to a capability to pick up advance information from the same cues used by intermediate and low-skilled players, highly skilled players demonstrated the additional, unique capability to pick up advance information from some specific early cues (especially bowling hand and arm cues) to which the less skilled players were not attuned. The acquisition of expert perceptual-motor skill appears to involve not only refinement of information extraction but also progression to the use of earlier, kinematically relevant sources of information.

A reflexive course for Masters students to understand and plan their own continuing professional development

Continuing Professional Development (CPD) is seen as a vital part of a professional engineer’s career, by professional engineering institutions as well as individual engineers. Factors such as ever-changing workforce requirements and rapid technological change have resulted in engineers no longer being able to rely just on the skills they learnt at university or can pick up on the job; they must undergo a structured professional development with clear objectives to develop further professional knowledge, values and skills. This paper presents a course developed for students undertaking a Master of Engineering or Master of Project Management at the University of Queensland. This course was specifically designed to help students plan their continuing professional development, while developing professional skills such as communication, ethical reasoning, critical judgement and the need for sustainable development. The course utilised a work integrated learning pedagogy applied within a formal learning environment, and followed the competency based chartered membership program of Engineers Australia, the peak professional body of engineers in Australia. The course was developed and analysed using an action learning approach. The main research question was “Can extra teaching and learning activities be developed that will simulate workplace learning?” The students continually assessed and reflected upon their current competencies, skills and abilities, and planed for the future attainment of specific competencies which they identified as important to their future careers. Various evaluation methods, including surveys before and after the course, were used to evaluate the action learning intervention. It was found that the assessment developed for the course was one of the most important factors, not only in driving student learning, as is widely accepted, but also in changing the students’ understandings and acceptance of the need for continuous professional development. The students also felt that the knowledge, values and skills they developed would be beneficial for their future careers, as they were developed within the context of their own professional development, rather than to just get through the course. © 2005, American Society for Engineering Education