Using pulse transit delay in Z-scan to discriminate between excited-state absorption and other nonlinear processes in ZnO nanocones

We report a new approach that uses the single beam Z-scan technique, to discriminate between excited state absorption (ESA) and two and three photon nonlinear absorption. By measuring the apparent delay or advance of the pulse in reaching the detector, the nonlinear absorption can be unambiguously identified as either instantaneous or transient. The simple method does not require a large range of input fluences or sophisticated pulse-probe experimental apparatus. The technique is easily extended to any absorption process dependent on pulse width and to nonlinear refraction measurements. We demonstrate in particular, that the large nonlinear absorption in ZnO nanocones when exposed to nanosecond 532 nm pulses, is due mostly to ESA, not pure two-photon absorption.

Total energy shaping of a class of underactuated Port-Hamiltonian Systems using a new set of closed-loop potential shape variables

This paper proposes a method for designing set-point regulation controllers for a class of underactuated mechanical systems in Port-Hamiltonian System (PHS) form. A new set of potential shape variables in closed loop is proposed, which can replace the set of open loop shape variables-the configuration variables that appear in the kinetic energy. With this choice, the closed-loop potential energy contains free functions of the new variables. By expressing the regulation objective in terms of these new potential shape variables, the desired equilibrium can be assigned and there is freedom to reshape the potential energy to achieve performance whilst maintaining the PHS form in closed loop. This complements contemporary results in the literature, which preserve the open-loop shape variables. As a case study, we consider a robotic manipulator mounted on a flexible base and compensate for the motion of the base while positioning the end effector with respect to the ground reference. We compare the proposed control strategy with special cases that correspond to other energy shaping strategies previously proposed in the literature.

Shaping lecturers’ beliefs about teaching and learning in higher education in the Pacific

The aim of this study was to describe the educational experiences shaping the teaching and learning beliefs held by a group of beginning lecturers in higher education at various tertiary institutions in the Pacific Island Countries (PICs). A total of sixty three essays written by participants in an online course on teaching in higher education comprised the data for the study. A modified version of narrative analysis was used. This is a powerful methodology in qualitative research that can provide remarkable insights into individuals’ beliefs. The critical experiences that were thought to shape their beliefs in teaching and learning were identified and discussed in the light of relevant literature. The participants described a range of influences that shaped their beliefs about teaching and learning including realisation about the need to work harder and know more, the importance of independence, support systems, curriculum, qualities of a teacher, teaching and learning process, teaching and learning strategies, and learning environments. This information was useful in teaching these students and for further courses.

Evaluation of resonant damping techniques for Z-source current-type inverter

For the renewable energy sources whose outputs vary continuously, a Z-source current-type inverter has been proposed as a possible buck-boost alternative for grid-interfacing. With a unique X-shaped LC network connected between its dc power source and inverter topology, Z-source current-type inverter is however expected to suffer from compounded resonant complications in addition to those associated with its second-order output filter. To improve its damping performance, this paper proposes the careful integration of Posicast or three-step compensators before the inverter pulse-width modulator for damping triggered resonant oscillations. In total, two compensators are needed for wave-shaping the inverter boost factor and modulation ratio, and they can conveniently be implemented using first-in first-out stacks and embedded timers of modern digital signal processors widely used in motion control applications. Both techniques are found to damp resonance of ac filter well, but for cases of transiting from current-buck to boost state, three-step technique is less effective due to the sudden intermediate discharging interval introduced by its non-monotonic stepping (unlike the monotonic stepping of Posicast damping). These findings have been confirmed both in simulations and experiments using an implemented laboratory prototype.

The SOLO Taxonomy as a means of shaping and assessing learning in higher education

This paper is a discussion of the use of the SOLO (Structure of Observed Learning Outcomes) Taxonomy (Biggs & Collis, 1982, 1989; Biggs, 1991, 1992a, 1992b; Boulton‐Lewis, 1992, 1994) as a means of developing and assessing higher order thinking in Higher Education. It includes a summary of the research into its use to date as an instrument to find out what students know and believe about their own learning, to assess entering knowledge in a discipline, to present examples of structural organization of knowledge in a discipline, to provide models of levels of desired learning outcomes, and in particular to assess learning outcomes. A proposal is made for further research.

The social shaping of packaged software selection

As organisations increasingly engage in the selection, purchase, and adoption of packaged software products, how these activities are carried out in practice becomes increasingly relevant for researchers and practitioners. Our focus in this paper is to propose a framework for understanding the packaged software selection process. The functionalist literature on this area of study suggests a number of generic recommendations, which are based on rational assumptions about the process and view the decision making that takes place as producing the “best technology solution.’” To explore this, we conducted a longitudinal, in-depth study of packaged software selection in a small organisation. For interpretation of the case, we draw upon the Social Construction of Technology, a theoretical framework arguing that technology is socially constituted and regarding the process of development as contradictory and uncertain. We offer a number of contributions. First, we further our understanding of packaged software selection with the critique that we offer of the functionalist literature, drawing insights from the emerging critical/constructivist literature and expanding our domain of interest to encompass the wider environment. Second, we weave this together with our experiences in the field, drawing on social constructivism for theoretical support, to develop a framework of packaged software selection that shows how various actors shape the process.

The knowing client : a processual perspective on knowledge shaping in consulting engagements

This thesis extends current understanding in management consulting research by investigating the ways in which management consultants and their clients shaped knowing over the course of nine different consulting engagements. The research illuminates the client experience of using consulting knowledge in organisations, and proposes a theoretical reconceptualisation of knowledge shaping in consulting engagements which incorporates how the knowing client is enacted. The research shows that knowledge shaping activities are planned and enacted to support novelty reduction in consulting engagements; that asymmetries in the structuring of the consultant–client relationship hamper knowledge transformation and the establishment of knowing; and that understanding of how the role identities of consultants and clients are established and maintained over the course of an engagement is integral to understanding knowledge shaping in consulting engagements.

Automated power semiconductor switching performance feature extraction from experimental double-pulse waveform data

Double-pulse tests are commonly used as a method for assessing the switching performance of power semiconductor switches in a clamped inductive switching application. Data generated from these tests are typically in the form of sampled waveform data captured using an oscilloscope. In cases where it is of interest to explore a multi-dimensional parameter space and corresponding result space it is necessary to reduce the data into key performance metrics via feature extraction. This paper presents techniques for the extraction of switching performance metrics from sampled double-pulse waveform data. The reported techniques are applied to experimental data from characterisation of a cascode gate drive circuit applied to power MOSFETs.

Shaping safe drinking cultures : evoking positive emotion to promote moderate-drinking behaviour

Social marketing by Western governments that use fear tactics and threatening information to promote anti-drinking messages has polarized ‘binge drinking’ and ‘moderate drinking’ through a continuum that implies benefits and harms for both individuals and society. With the goal of extending insights into social marketing approaches that promote safer drinking cultures in Australia, we discuss findings from a study that examines alcohol consumers' moderate-drinking intentions. By applying the theory of planned behaviour and emotions theory, we discuss survey results from a sample of alcohol consumers, which demonstrate that positively framed value propositions that evoke happiness and love are more influential in the processing of an alcohol moderation message for alcohol consumers. The key limitations of this study are the cross-sectional nature of the data and the focal-dependent variable being behavioural intentions rather than behaviours. Research insight into the stronger influence of positive emotions on processing an alcohol moderation message establishes an important avenue for future social marketing communications that moves beyond negative, avoidance appeals to promote behaviour change in drinkers. These research findings will benefit professionals involved in developing social change campaigns that promote and reinforce consumers' positive intentions, with messages about the benefits of controlled, moderate drinking.

The arts and education for sustainability : shaping student teachers' identities towards sustainability

The Arts are acknowledged for their potential in providing learners with multiple 'languages' with which they might make their learning visible across all levels of education. This chapter explores how the integration of the Arts and education for sustainabilty can provide expanded opportunities for seeing, understanding and responding to the sustainability imperative. Such approaches encourage broad engagement and expression of ideas about sustainability that extend beyond more common approaches that have mostly responded to sustainability through the languages of the Sciences and geography. Traditionally, the Arts have been valued highly by the early childhood education field and typically lie at the heart of early childhood programs. Increasing engagement with the sustainability agenda in early childhood contexts suggests that teachers might find ways to integrate early education for sustainability with the Arts in meaningful ways. This chapter explores how an integrated Arts and Humanities subject in an early childhood teacher education course in Queensland, Australia provides a context for the integration of sustainability as a cross-curricular thread in teacher education, reflecting recent national curriculum innovation in Australia.

Characteristics of the first pre-discharge current pulse in SF6 under a steep fronted impulse voltage

An improved understanding of the characteristics of the pre-discharge current pulses in GIS will lead to improved analyses of the results from the UHF partial discharge detection method. This paper presents the characteristics of the first pre-discharge current pulses from a point-to-plain geometry at 1 bar absolute under both polarities of a 1.1/80 us lightning impulse. The analysis has shown that the pre-discharge current wave shape, peak current magnitude and charge is effected by the instantaneous voltage at which the pre- discharge took place as well as the polarity of the active electrode. The measured results show that protrusions on the electrodes have slower wave shape parameters than those reported for free conducting particles.

Emerging Powerful Southern Voices: Role of BASIC Nations in Shaping Climate Change Mitigation Commitments

This book chapter explores the role of Brazil, China, India and South Africa (BASIC) in shaping mitigation commitments within the United Nations Framework Convention on Climate Change (UNFCCC)

Technology-mediated tools for shaping experiences in urban commuter trains

This thesis presents the results of a study into ways that technology can be appropriated and designed to support urban rail commuters in their daily journeys. The study evaluated a mobile application prototype deployed along the Brisbane passenger rail network. This prototype was designed to support social interaction between passengers sharing the same trains. This thesis provides a step forward in showing the relevance of increasingly creating solutions that contribute to a more enjoyable and attractive public transport service.

Shaping development through mechanical strain: The transcriptional basis of diet-induced phenotypic plasticity in a cichlid fish

Adaptive phenotypic plasticity, the ability of an organism to change its phenotype to match local environments, is increasingly recognized for its contribution to evolution. However, few empirical studies have explored the molecular basis of plastic traits. The East African cichlid fish Astatoreochromis alluaudi displays adaptive phenotypic plasticity in its pharyngeal jaw apparatus, a structure that is widely seen as an evolutionary key innovation that has contributed to the remarkable diversity of cichlid fishes. It has previously been shown that in response to different diets, the pharyngeal jaws change their size, shape and dentition: hard diets induce an adaptive robust molariform tooth phenotype with short jaws and strong internal bone structures, while soft diets induce a gracile papilliform tooth phenotype with elongated jaws and slender internal bone structures. To gain insight into the molecular underpinnings of these adaptations and enable future investigations of the role that phenotypic plasticity plays during the formation of adaptive radiations, the transcriptomes of the two divergent jaw phenotypes were examined. Our study identified a total of 187 genes whose expression differs in response to hard and soft diets, including immediate early genes, extracellular matrix genes and inflammatory factors. Transcriptome results are interpreted in light of expression of candidate genesmarkers for tooth size and shape, bone cells and mechanically sensitive pathways. This study opens up new avenues of research at new levels of biological organization into the roles of phenotypic plasticity during speciation and radiation of cichlid fishes.