Performance of a cognitive, but not visual, secondary task interacts with alcohol-induced balance impairment in novice and experienced motorcycle riders

The appropriateness of applying drink driving legislation to motorcycle riding has been questioned as there may be fundamental differences in the effects of alcohol on driving and motorcycling. It has been suggested that alcohol may redirect riders’ focus from higher-order cognitive skills such as cornering, judgement and hazard perception, to more physical skills such as maintaining balance. To test this hypothesis, the effects of low doses of alcohol on balance ability were investigated in a laboratory setting. The static balance of twenty experienced and twenty novice riders was measured while they performed either no secondary task, a visual (search) task, or a cognitive (arithmetic) task following the administration of alcohol (0%, 0.02%, and 0.05% BAC). Subjective ratings of intoxication and balance impairment increased in a dose-dependent manner in both novice and experienced motorcycle riders, while a BAC of 0.05%, but not 0.02%, was associated with impairments in static balance ability. This balance impairment was exacerbated when riders performed a cognitive, but not a visual, secondary task. Likewise, 0.05% BAC was associated with impairments in novice and experienced riders’ performance of a cognitive, but not a visual, secondary task, suggesting that interactive processes underlie balance and cognitive task performance. There were no observed differences between novice vs. experienced riders on static balance and secondary task performance, either alone or in combination. Implications for road safety and future ‘drink riding’ policy considerations are discussed.

Impairment of simulated motorcycle riding performance under low dose alcohol

Crash statistics that include the blood alcohol concentration (BAC) of vehicle operators reveal that crash involved motorcyclists are over represented at low BACs (e.g., ≤0.05%). This riding simulator study compared riding performance and hazard response under three low dose alcohol conditions (sober, 0.02% BAC, 0.05% BAC). Forty participants (20 novice, 20 experienced) completed simulated rides in urban and rural scenarios while responding to a safety-critical peripheral detection task (PDT). Results showed a significant increase in the standard deviation of lateral position in the urban scenario and PDT reaction time in the rural scenario under 0.05% BAC compared with zero alcohol. Participants were most likely to collide with an unexpected pedestrian in the urban scenario at 0.02% BAC, with novice participants at a greater relative risk than experienced riders. Novices chose to ride faster than experienced participants in the rural scenario regardless of BAC. Not all results were significant, emphasising the complex situation of the effects of low dose BAC on riding performance, which needs further research. The results of this simulator study provide some support for a legal BAC for motorcyclists below 0.05%.

Brake system performance requirements of a lightweight electric/hybrid rear wheel drive vehicle

Investigates the braking performance requirements of the UltraCommuter, a lightweight series hybrid electric vehicle currently under development at the University of Queensland. With a predicted vehicle mass of 600 kg and two in-wheel motors each capable of 500 Nm of peak torque, decelerations up to 0.46 g are theoretically possible using purely regenerative braking. With 99% of braking demands less than 0.35 g, essentially all braking can be regenerative. The wheel motors have sufficient peak torque capability to lock the rear wheels in combination with front axle braking, eliminating the need for friction braking at the rear. Emergency braking levels approaching 1 g are achieved by supplementation with front disk brakes. This paper presents equations describing the peak front and rear axle braking forces which occur under straight line braking, including gradients. Conventionally, to guarantee stability, mechanical front/rear proportioning of braking effort ensures that the front axle locks first. In this application, all braking is initially regenerative at the rear, and an adaptive ''by-wire'' proportioning system presented ensures this stability requirement is still satisfied. Front wheel drive and all wheel drive systems are also discussed. Finally, peak and continuous performance measures, not commonly provided for friction brakes, are derived for the UltraCommuter's motor capability and range of operation.

Metastability and emergent performance of dynamic interceptive actions

Objectives: Adaptive patterning of human movement is context specific and dependent on interacting constraints of the performer–environment relationship. Flexibility of skilled behaviour is predicated on the capacity of performers to move between different states of movement organisation to satisfy dynamic task constraints, previously demonstrated in studies of visual perception, bimanual coordination, and an interceptive combat task. Metastability is a movement system property that helps performers to remain in a state of relative coordination with their performance environments, poised between multiple co-existing states (stable and distinct movement patterns or responses). The aim of this study was to examine whether metastability could be exploited in externally paced interceptive actions in fast ball sports, such as cricket. Design: Here we report data on metastability in performance of multi-articular hitting actions by skilled junior cricket batters (n = 5). Methods: Participants’ batting actions (key movement timings and performance outcomes) were analysed in four distinct performance regions varied by ball pitching (bounce) location. Results: Results demonstrated that, at a pre-determined distance to the ball, participants were forced into a meta-stable region of performance where rich and varied patterns of functional movement behaviours emerged. Participants adapted the organisation of responses, resulting in higher levels of variability in movement timing in this performance region, without detrimental effects on the quality of interceptive performance outcomes. Conclusions: Findings provide evidence for the emergence of metastability in a dynamic interceptive action in cricket batting. Flexibility and diversity of movement responses were optimised using experiential knowledge and careful manipulation of key task constraints of the specific sport context.

Echo theatre : from experience to performance

This research project investigates the characteristics of Echo Theatre, its potential to foster performative and narrative competencies in students, and the role of the teacher in this performative and educational practice. Echo Theatre is a method devised during my storytelling practice and this research confirms that there is no identical research or teaching practice which involves students staging personal narratives in the classroom in this way. The study has been informed by crossdisciplinary theory studies from the fields of phenomenology, cognitive sciences, and theatre practice. To analyse and discuss Echo Theatre's potential contribution to the development of the child I have defined the concept of a performative competence as well as redefined the concept of a narrative competence. The situated, embodied and performative character of human cognition is emphasised as physical actions and thinking in movement is related to both gestural and conceptual understandings. Studies in philosophy and psychology confirm that narrative structure, related to identity construction and meaning-­‐making, can be attained through the performing body. We tell stories to know who we are. Telling stories then in the Echo Theatre model develops multiple competencies related to the performative aspects of theatre practice as well as the narrative aspects of storytelling. The practice-­‐led aspect of this research project includes two fieldwork projects involving a primary school class who created sixteen different Echo Theatre stories. Student participation reveals that Echo Theatre is most constructive when it moves through five phases; recalled experience, narrative, drama, performance, and evaluation. Ongoing reflection is a part of all five phases. The study also confirms that while there is potential for Echo Theatre to support the development of performative and narrative competencies in students, the effectiveness of this directly relates to the teacher's theatre knowledge and skills and his or her didactic attitude towards the students. This study confirms that the potential for learning through the moving and performing body of Echo Theatre is strengthened by working with personal narratives in the classroom and led by teachers displaying heightened skills and knowledge of the aesthetics and dynamics of theatrical form.

Star performers : task and contextual performance are components, but are they enough?

Identifying outstanding performers or ‘stars’ is a critical component of managing talent. However, organizational effectiveness in this area is limited by the current lack of guidance about the behaviour and characteristics of stars. We address this gap by combining a conceptual analysis with an empirical study involving 174 managers. Conceptually we examine the alignment of managers’ perceptions of outstanding performance with the well established task and contextual performance model and find this framework accounts for a core element in managers’ judgments about outstanding performers. However, a second, more qualitative approach finds that other dimensions including being self-directed, and a willingness to lead are also important. Our findings are consistent with a long-term trend toward identifying work effectiveness with highly discretionary, psychological and behavioural elements, and we consider the implications of this for the study and management of high level, individual effectiveness.

Filter and control performance bounds in the presence of model uncertainties with aerospace applications

This thesis establishes performance properties for approximate filters and controllers that are designed on the basis of approximate dynamic system representations. These performance properties provide a theoretical justification for the widespread application of approximate filters and controllers in the common situation where system models are not known with complete certainty. This research also provides useful tools for approximate filter designs, which are applied to hybrid filtering of uncertain nonlinear systems. As a contribution towards applications, this thesis also investigates air traffic separation control in the presence of measurement uncertainties.

Training for performance : insights from molecular biology

In this commentary the authors discuss the molecular basis of the training adaptation and review the role of several key signaling proteins important in the adaptation to endurance and resistance training.

Effect of recovery modality on 4-hour repeated treadmill running performance and changes in physiological variables

The purpose of this study was to compare the effectiveness of three different recovery modalities - active (ACT), passive (PAS) and contrast temperature water immersion (CTW) - on the performance of repeated treadmill running, lactate concentration and pH. Fourteen males performed two pairs of treadmill runs to exhaustion at 120% and 90% of peak running speed (PRS) over a 4-hour period. ACT, PAS or CTW was performed for 15-min after the first pair of treadmill runs. ACT consisted of running at 40% PRS, PAS consisted of standing stationary and CTW consisted of alternating between 60-s cold (10°C) and 120-s hot (42°C) water immersion. Run times were converted to time to cover set distance using critical power. Type of recovery modality did not have a significant effect on change in time to cover 400 m (Mean±SD; ACT 2.7±3.6 s, PAS 2.9±4.2 s, CTW 4.2±6.9 s), 1000 m (ACT 2.2±4.0 s, PAS 4.8±8.6 s, CTW 2.1±7.2 s) or 5000 m (ACT 1.4±29.0 s, PAS 16.7±58.5 s, CTW 11.7±33.0 s). Post exercise blood lactate concentration was lower in ACT and CTW compared with PAS. Participants reported an increased perception of recovery in the CTW compared with ACT and PAS. Blood pH was not significantly influenced by recovery modality. Data suggest both ACT and CTW reduce lactate accumulation after high intensity running, but high intensity treadmill running performance is returned to baseline 4-hours after the initial exercise bout regardless of the recovery strategy employed.

The relationship of entrepreneurial orientation, Vincentian values and economic and social performance in social enterprise

This study focuses on the managerial question “should social enterprises become more entrepreneurial?” It adapts the Covin and Slevin (1989) entrepreneurial orientation scale to measure the adoption of entrepreneurship by a social enterprise, and develops a scale that combines a Vincentian based focus to serve the poor with a propensity to take a more entrepreneurial approach toward business as a measure of a social value orientation (SVO).

Measurement as legitimacy versus legitimacy of measures : Performance evaluation of social enterprise

Purpose The purpose of this paper is to review the growing emphasis on quantifiable performance measures such as social return on investment (SROI) in third sector organisations – specifically, social enterprise – through a legitimacy theory lens. It then examines what social enterprises value (i.e. consider important) in terms of performance evaluation, using a case study approach. Design/methodology/approach Case studies involving interviews, documentary analysis, and observation, of three social enterprises at different life-cycle stages with different funding structures, were constructed to consider “what measures matter” from a practitioner's perspective. Findings Findings highlight a priority on quality outcomes and impacts in primarily qualitative terms to evaluate performance. Further, there is a noticeable lack of emphasis on financial measures other than basic access to financial resources to continue pursuing social goals. Social implications The practical challenges faced by social enterprises – many of which are small to medium sized – in evaluating performance and by implication organisational legitimacy are contrasted with measures such as SROI which are resource intensive and have inherent methodological limitations. Hence, findings suggest the limited and valuable resources of social enterprises would be better allocated towards documenting the actual outcomes and impacts as a first step, in order to evaluate social and financial performance in terms appropriate to each objective, in order to demonstrate organisational legitimacy. Originality/value Findings distinguish between processes which may hold symbolic legitimacy for select stakeholder groups, and processes which hold substantive, cognitive legitimacy for stakeholders more broadly, in the under-researched context of social enterprise.

Engineering electrodeposited ZnO films and their memristive switching performance

We report the influence of zinc oxide (ZnO) seed layers on the performance of ZnO-based memristive devices fabricated using an electrodeposition approach. The memristive element is based on a sandwich structure using Ag and Pt electrodes. The ZnO seed layer is employed to tune the morphology of the electrodeposited ZnO films in order to increase the grain boundary density as well as construct highly ordered arrangements of grain boundaries. Additionally, the seed layer also assists in optimizing the concentration of oxygen vacancies in the films. The fabricated devices exhibit memristive switching behaviour with symmetrical and asymmetrical hysteresis loops in the absence and presence of ZnO seed layers, respectively. A modest concentration of oxygen vacancy in electrodeposited ZnO films as well as an increase in the ordered arrangement of grain boundaries leads to higher switching ratios in Ag/ZnO/Pt devices.

2 Hour game jam at SLQ Garage Gamer - Live performance with crowd participation

The 2 hour game jam was performed as part of the State Library of Queensland 'Garage Gamer' series of events, summer 2013, at the SLQ exhibition. An aspect of the exhibition was the series of 'Level Up' game nights. We hosted the first of these - under the auspices of brIGDA, Game On. It was a party - but the focal point of the event was a live streamed 2 hour game jam. Game jams have become popular amongst the game development and design community in recent years, particularly with the growth of the Global Game Jam, a yearly event which brings thousands of game makers together across different sites in different countries. Other established jams take place on-line, for example the Ludum Dare challenge which as been running since 2002. Other challenges follow the same model in more intimate circumstances and it is now common to find institutions and groups holding their own small local game making jams. There are variations around the format, some jams are more competitive than others for example, but a common aspect is the creation of an intense creative crucible centred around team work and ‘accelerated game development’. Works (games) produced during these intense events often display more experimental qualities than those undertaken as commercial projects. In part this is because the typical jam is started with a conceptual design brief, perhaps a single word, or in the case of the specific game jam described in this paper, three words. Teams have to envision the challenge key word/s as a game design using whatever skills and technologies they can and produce a finished working game in the time given. Game jams thus provide design researchers with extraordinary fodder and recent years have also seen a number of projects which seek to illuminate the design process as seen in these events. For example, Gaydos, Harris and Martinez discuss the opportunity of the jam to expose students to principles of design process and design spaces (2011). Rouse muses on the game jam ‘as radical practice’ and a ‘corrective to game creation as it is normally practiced’. His observations about his own experience in a jam emphasise the same artistic endeavour forefronted earlier, where the experience is about creation that is divorced from the instrumental motivations of commercial game design (Rouse 2011) and where the focus is on process over product. Other participants remark on the social milieu of the event as a critical factor and the collaborative opportunity as a rich site to engage participants in design processes (Shin et al, 2012). Shin et al are particularly interested in the notion of the site of the process and the ramifications of participants being in the same location. They applaud the more localized event where there is an emphasis on local participation and collaboration. For other commentators, it is specifically the social experience in the place of the jam is the most important aspect (See Keogh 2011), not the material site but rather the physical embodied experience of ‘being there’ and being part of the event. Participants talk about game jams they have attended in a similar manner to those observations made by Dourish where the experience is layered on top of the physical space of the event (Dourish 2006). It is as if the event has taken on qualities of place where we find echoes of Tuan’s description of a particular site having an aura of history that makes it a very different place, redolent and evocative (Tuan 1977). The 2 hour game jam held during the SLQ Garage Gamer program was all about social experience.

Ergodic capacity and outage performance of amplify-and-forward protocols

This thesis analyses the performance bounds of amplify-and-forward relay channels which are becoming increasingly popular in wireless communication applications. The statistics of cascaded Nakagami-m fading model which is a major obstacle in evaluating the outage of wireless networks is analysed using Mellin transform. Furthermore, the upper and the lower bounds for the ergodic capacity of the slotted amplify-and-forward relay channel, for finite and infinite number of relays are derived using random matrix theory. The results obtained will enable wireless network designers to optimize the network resources, benefiting the consumers.