Limits of spherical blur determined with an adaptive optics mirror

We extended an earlier study (Vision Research, 45, 1967–1974, 2005) in which we investigated limits at which induced blur of letter targets becomes noticeable, troublesome and objectionable. Here we used a deformable adaptive optics mirror to vary spherical defocus for conditions of a white background with correction of astigmatism; a white background with reduction of all aberrations other than defocus; and a monochromatic background with reduction of all aberrations other than defocus. We used seven cyclopleged subjects, lines of three high-contrast letters as targets, 3–6 mm artificial pupils, and 0.1–0.6 logMAR letter sizes. Subjects used a method of adjustment to control the defocus component of the mirror to set the 'just noticeable', 'just troublesome' and 'just objectionable' defocus levels. For the white-no adaptive optics condition combined with 0.1 logMAR letter size, mean 'noticeable' blur limits were ±0.30, ±0.24 and ±0.23 D at 3, 4 and 6 mm pupils, respectively. White-adaptive optics and monochromatic-adaptive optics conditions reduced blur limits by 8% and 20%, respectively. Increasing pupil size from 3–6 mm decreased blur limits by 29%, and increasing letter size increased blur limits by 79%. Ratios of troublesome to noticeable, and of objectionable to noticeable, blur limits were 1.9 and 2.7 times, respectively. The study shows that the deformable mirror can be used to vary defocus in vision experiments. Overall, the results of noticeable, troublesome and objectionable blur agreed well with those of the previous study. Attempting to reduce higher-order aberrations or chromatic aberrations, reduced blur limits to only a small extent.

Nanoparticle melting as a Stefan moving boundary problem

The melting of spherical nanoparticles is considered from the perspective of heat flow in a pure material and as a moving boundary (Stefan) problem. The dependence of the melting temperature on both the size of the particle and the interfacial tension is described by the Gibbs-Thomson effect, and the resulting two-phase model is solved numerically using a front-fixing method. Results show that interfacial tension increases the speed of the melting process, and furthermore, the temperature distribution within the solid core of the particle exhibits behaviour that is qualitatively different to that predicted by the classical models without interfacial tension.

The Dystopian Mirror and the Female Body

Women’s experience of the change room mirror is not a particularly affirmative one. The pleasure in looking at the self is dissipated by the ideal feminine ‘I’ that hovers in the shadows of their image of self and others constructing dystopian surveillance and entrapment. This article considers the responses of a number of women bloggers who describe their negative experiences in front of change room mirrors. It also argues that the mirror has been used in positive and creative ways by women artists to assert a self that is not subject to a critical gaze.

Moving towards open standards

Standards are designed to promote the interoperability of products and systems by enabling different parties to develop technologies that can be used together. There is an increasing expectation in many technical communities, including open source communities, that standards will be ‘open’. However, standards are subject to legal rights which impact upon, not only their development, but also their implementation. Of central importance are intellectual property rights: technical standards may incorporate patented technologies, while the specification documents of standards are protected by copyright. This article provides an overview of the processes by which standards are developed and considers the concept of ‘interoperability’, the meaning of the term ‘open standard’ and how open standards contribute to interoperability. It explains how intellectual property rights operate in relation to standards and how they can be managed to create standards that are open, not only during their development, but also in implementation.

Mirror, mirror on the wall, who is the happiest of them all?

This paper turns Snow-White's magic mirror onto recent economics Nobel Prize winners, top economists and happiness researchers, and through the eyes of the 'man in the street' seeks to determine who the happiest academic is. The study not only provides a clear answer to this question but also unveils who is the ladies' man and who is the sweetheart of the aged. It also explores the extent to which information matters and whether individuals' self-reported happiness affects their perceptions about the happiness of these superstars in economics.

Accelerated computation of cyclic steady state for simulated-moving-bed processes

Industrial applications of the simulated-moving-bed (SMB) chromatographic technology have brought an emergent demand to improve the SMB process operation for higher efficiency and better robustness. Improved process modelling and more-efficient model computation will pave a path to meet this demand. However, the SMB unit operation exhibits complex dynamics, leading to challenges in SMB process modelling and model computation. One of the significant problems is how to quickly obtain the steady state of an SMB process model, as process metrics at the steady state are critical for process design and real-time control. The conventional computation method, which solves the process model cycle by cycle and takes the solution only when a cyclic steady state is reached after a certain number of switching, is computationally expensive. Adopting the concept of quasi-envelope (QE), this work treats the SMB operation as a pseudo-oscillatory process because of its large number of continuous switching. Then, an innovative QE computation scheme is developed to quickly obtain the steady state solution of an SMB model for any arbitrary initial condition. The QE computation scheme allows larger steps to be taken for predicting the slow change of the starting state within each switching. Incorporating with the wavelet-based technique, this scheme is demonstrated to be effective and efficient for an SMB sugar separation process. Moreover, investigations are also carried out on when the computation scheme should be activated and how the convergence of the scheme is affected by a variable stepsize.

The development of a "Good Practice Guide" for first year curriculum development, revision and evaluation : a moving feast

Since 2002 QUT has sponsored a range of first year-focussed initiatives, most recently the Transitions In Project (TIP) which was designed to complement the First Year Experience Program and be a capacity building initiative. A primary focus of TIP was The First Year Curriculum Project: the review, development, implementation and evaluation of first year curriculum which has culminated in the development of a “Good Practice Guide” for the management of large first year units. First year curriculum initiates staff-student relationships and provides the scaffolding for the learning experience and engagement. Good practice in first year curriculum is within the control of the institution and can be redesigned and reviewed to improve outcomes. This session will provide a context for the First Year Curriculum Project and a concise overview of the suite of resources developed that have culminated in the Good Practice Guide.

Moving Forward: Students and teachers against racism

Racism in education is one of the key issues facing schools, communities and the nation. Racism is about the exercise of power by individuals, groups and communities against each other. Whatever form it takes, racism has great potential to hurt and to harm. This book tells a series of stories from 11 very different government and non-government schools in Queensland. These stories show the positive measures that are being taken in schools to promote harmony, respect, understanding and fairness between school members, and with people in the community. The stories offer a simple lesson: solutions to racism must be local solutions. They must be culturally appropriate and relevant to specific communities. There is no single solution. However, this book shows that, through a mixture of strategies, students, teachers, schools and communities can make a difference, influencing the school and community culture and improving the educational outcomes and life chances of students of diverse backgrounds.

Peak power demand reduction under moving block signalling using an expert system

The concept of moving block signallings (MBS) has been adopted in a few mass transit railway systems. When a dense queue of trains begins to move from a complete stop, the trains can re-start in very close succession under MBS. The feeding substations nearby are likely to be overloaded and the service will inevitably be disturbed unless substations of higher power rating are used. By introducing starting time delays among the trains or limiting the trains’ acceleration rate to a certain extent, the peak energy demand can be contained. However, delay is introduced and quality of service is degraded. An expert system approach is presented to provide a supervisory tool for the operators. As the knowledge base is vital for the quality of decisions to be made, the study focuses on its formulation with a balance between delay and peak power demand.