4,632 research outputs found

    Observation of robust flat-band localization in driven photonic rhombic lattices

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    We demonstrate that a flat-band state in a quasi-one-dimensional rhombic lattice is robust in the presence of external drivings along the lattice axis. The lattice was formed by periodic arrays of evanescently coupled optical waveguides, and the external drivings were realized by modulating the paths of the waveguides. We excited a superposition of flat-band eigenmodes at the input and observed that this state does not diffract in the presence of static as well as high-frequency sinusoidal drivings. This robust localization is due to destructive interference of the analogous wavefunction and is associated with the symmetry in the lattice geometry. We then excited the dispersive bands and observed Bloch oscillations and coherent destruction of tunneling. {\textcopyright} 2017 Optical Society of America.Comment: 5 pages, 7 figure

    Financial Exigency: Need It Affect the Quality of Biology Curricula?

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    Declining enrollments and financial restraints require that science departments seek ways to meet academic commitments within the framework of reduced budgets and faculty resources without sacrificing quality programs. The following describes our evaluation of the role of the laboratory in the undergraduate biology curriculum and the positive effects achieved on our academic, financial, and faculty resources by separating labs from lecture courses and reducing the number of labs required for majors and nonmajors. Several years ago we experienced increased enrollments coupled with only modest increases in funds to deliver our undergraduate instructional programs. To resolve this problem we developed a new approach to the role of lecture and laboratory courses for our biology majors, the nonmajor, and the students in the allied health programs serviced by our department. The changes effected by us then would appear to be equally appropriate in today\u27s economy when inflationary pressures and a decline in students make it imperative that departments look to ways to meet their academic commitments within the framework of declining budgets and faculty resources

    Leadership for innovation – why manufacturing has a future in Australia

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    In this paper, business leaders discuss the leadership styles they have used to ensure their companies are manufacturing success stories, and then these experiences are analysed to outline the leadership needs for innovation in Australia. Introduction With dire predictions about the future of manufacturing in Australia, we should remember that manufacturing has been an important contributor to national development. There was a thriving manufacturing industry up to 1945, sufficient to supply most domestic needs. Post-war, new industries flourished and a golden era of manufacturing followed. By the late 1950s manufacturing accounted for 29% of Australia’s GDP. By the 1960s, growth and productivity was faltering and manufacturing had begun to stagnate. Today, manufacturing accounts for less than 10% of Australia’s GDP, the lowest level since early colonial times. This is due, in large part, to global economic changes and the economic processes of comparative advantage. However, the innovative spirit that drove previous successes remains and a new generation of leaders and enterprises has emerged. Two of these innovative leaders presented case studies of their firms at a Swinburne Leadership Dialogue in June 2014. Richard Simpson of Furnace Engineering and Robert Wilson of the Wilson Transformer Company discussed the leadership styles and approaches they have used to ensure their companies are – and remain – national manufacturing success stories. Scott Thompson-Whiteside of Swinburne University of Technology then analyses their experiences to outline the leadership needs for innovation in Australia

    Growth and volatility regime switching models for New Zealand GDP data

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    This paper fits hidden Markov switching models to New Zealand GDP data. A primary objective is to better understand the utility of these methods for modelling growth and volatility regimes present in the New Zealand data and their interaction. Properties of the models are developed together with a description of the estimation methods, including use of the Expectation Maximisation (EM) algorithm. The models are fitted to New Zealand GDP and production sector growth rates to analyse changes in their mean and volatility over time. The paper discusses applications of the methodology to identifying changes in growth performances, and examines the timing of growth and volatility regime switching between production sectors. Conclusions to emerge are that, in contrast to the 1980s, New Zealand GDP growth experienced an unusually long period of time in high growth and low volatility regimes during the 1990s. The paper evaluates sector contributions to this 1990s experience and discusses directions for further development.Hidden Markov models; regime switching; growth; business cycles; volatility; production sectors; GDP.

    Calm after the Storm?: Supply-side contributions to New Zealand’s GDP volatility decline

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    The variance of New Zealand’s real GDP has declined since the mid-1980s. To investigate why, this paper decomposes the variance of chain-weighted estimates of production-based real GDP growth into sector shares, sector growth rate variances and co-variances. The principal explanation for the decline in GDP volatility is a fall in the sum of sector variances driven by a decline in the Services and Manufacturing sector production growth variances. Sector co-variances have had a dominant influence on the profile of GDP volatility and this influence has not diminished. Despite marked changes in sector shares, notably increases in Services and Primary sector shares and a decrease in the share of Manufacturing, this has not been a significant factor influencing the decline in GDP volatility. We postulate that policy interventions such as “Think Big”, regulatory interventions during the early 1980s, and the introduction of GST are key explanations for the higher volatility until the mid 1980s. Cessation of these interventions, deregulation and possibly changes in inventory management methods are important reasons why GDP volatility has fallen since then.Volatility, growth, production sector shares, manufacturing, services, primary, construction.

    The effect of clearance spaces in air compressor cylinders: with notes on air compressors and air measurement.

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    [Supported by a published paper entitled “Method of estimating the slip in air compressors by altering the clearance volume."]In comparison with the experimental research which has been devoted to the internal combustion engine there is a lack of thorough research into the problems inherent in air compressors, with the result that the problems met with in the study of air compression cover a wide field. The main purport of this thesis is to investigate the beneficial and adverse effects of large and small clearance spaces in air compressor cylinders and to show that altered clearance offers a means of arriving at an approximation to a compressor's air slip.Since the sizes and types of compressor valves fitted more or less determine the volume of the clearance space and since small valves have high, and large valves low air speeds through them, effort usually seeks to achieve a suitable compromise, securing at once a fairly small clearance and a reasonably slow passage of air. The essence is that it is hoped that the tests carried out with altered clearance will prove that the effect of clearance below a certain pressure may be neglected, but that above this pressure clearance has an increasingly adverse influence.The fact that the theoretical volumetric efficiency is a linear function of the clearance at any delivery pressure suggests a means, if it can be shown that the actual actual volumetric efficiency is also of straight line form, of estimating at zero clearance the volumetric efficiency and hence the air slip. (This is discussed in the enclosed publication - "Engineering," 7th August 1936, p.138-139.)Information has been gathered and recorded regard - :ing types of valves, air speeds through them, typical clearance percentages allowed in practice, mean values of the compression exponent and the effect of cooling.A section has been devoted to reviewing a few of the most common methods of measuring air quantities, particular comparison being drawn between the British and .merican commercial practices. Several methods are in existence for measuring air, and, although reasonable accuracy can be attained by most of them when correctly applied in a scientific laboratory, it is only within recent years that a standard apparatus has been adopted for commercial tests.Another section is given to a description of the Compressor and Air Measurement Plant installed in Edinburgh University, for the design of which the author was partly responsible,

    Evolutionary design of digital VLSI hardware

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    Evaluating emotional distress and health-related quality of life in patients with heart failure and their family caregivers:Testing dyadic dynamics using the Actor-Partner Interdependence Model

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    Purpose: 1) To compare levels of emotional symptoms and health-related quality of life between patients with heart failure and their family caregivers; and 2) to examine whether patients’ and caregivers’ emotional symptoms were associated with their own, as well as their partner’s health-related quality of life. Method: In this cross-sectional study, 41 patients-caregiver dyads (78% male patients, aged 68.6 years; and 83% female caregivers, aged 65.8 years) completed all nine dimensions of the Brief Symptom Inventory and the Minnesota Living with Heart failure Questionnaire. Dyadic data were analysed for 6 sub-scales of the Brief Symptom Inventory, using the Actor–Partner Interdependence Model. Results: There were no statistically significant differences in emotional symptoms and health-related quality of life between patients with heart failure and their caregivers. Patients’ and caregivers’ emotional symptoms were associated with their own health-related quality of life. Caregivers’ anxiety, phobic anxiety, obsession-compulsion, depression and hostility negatively influenced their partner’s (i.e. the patient’s) health-related quality of life. There were no partner effects of patients’ emotional symptoms on the health-related quality of life of caregivers. Conclusions: The results of this study suggest that patients may be particularly vulnerable to the emotional distress, i.e. thoughts, impulses and actions of their caregivers. It may be possible to improve patients’ health-related quality of life by targeting specific detrimental emotional symptoms of caregivers
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