662 research outputs found
Dispersion of silicon based micro-and nano-photonic structures and its device applications
No full textSignificant dispersion can occur in silicon micro- and nano-photonic structures, such as photonic crystals and microresonators. These dispersions may cause the phase shift and group velocity of light to be highly wavelength dependent along a fixed propagation path, or cause the propagation direction of light to be highly sensitive to the wavelength. These two types of effects are called longitudinal dispersion and angular dispersion, respectively. The slow-light effect is due to the longitudinal dispersion, and the angular dispersion is associated with the superprism effect in photonic crystals. Though, longitudinal dispersion has a less apparent influence on the superprism effect, as revealed through a more in-depth analysis. A synergistic theoretical framework of the dispersions is developed to enable a common examination of the longitudinal and angular dispersion in photonic crystal structures. These dispersive effects can lead to undesirable consequences, such as large losses and/or narrow bandwidths. For the slow-light effect, a basic proof will be shown for the scaling of random scattering losses due to fabrication imperfections in a photonic crystal waveguide. For the superprism effect, a fundamental limit, the bandwidth-sensitivity product, will be presented that governs the maximum angular sensitivities and the achievable bandwidth. This product is the counterpart of the bandwidth-delay product for the slow-light effect. A parallel-coupled dual racetrack silicon resonator structure is proposed and analyzed for arbitrary quadrature signal generation. The over-coupled, critically-coupled, and under-coupled scenarios are systematically studied. Simulations indicate that only the over-coupled structures can generate arbitrary quadrature signals. The effects of potential asymmetries in the coupling constants and quality factors of the two racetrack resonators are systematically studied. It is shown that these asymmetry effects can be compensated by small phase shifts in the two racetracks. The design, fabrication and characterization of silicon waveguides, resonator and periodic structures, including the parallel-coupled dual racetrack structure, will also be presented. The results have shown successful coupling of resonators. With the high dispersion of silicon micro- and nano-photonic structures, light can be modulated, switched, and steered with higher efficiency and lower power consumption. Thus this study may contribute to saving energy in photonic devices.Ph.D.Includes bibliographical referencesIncludes vitaby Ryan Anthony Integli
Agenda for change: strategic choices for the next government
No full textThe next government has a primary requirement to be well briefed on the challenges inherent in Australia’s strategic circumstances and the policy options available to it. ASPI is publishing this report to layout our strategic choices and to provide recommendations.
Contributors are Peter Jennings on strategic policy, Mark Thomson and Andrew Davies on defence, Anthony Bergin and Kristy Bryden on homeland security, Russell Trood on foreign policy and Ryan Stokes on economic security.
This body of ideas makes a compelling contribution to the discussions which ought always to characterise the Australian strategic and defence debate
Comparison of Two Gingival Displacement Procedures; a Pilot Study
No full textObjective: The primary objective was to examine if a cordless gingival displacement procedure displaces sulcular tissue to facilitate acceptable impressions for fixed prosthodontic restorations. Materials and Methods: Fifteen (15) patients were recruited; cordless impressions (n=7) and conventional corded impression (n=8) were made during routine treatment for fixed dental prostheses. Results: Fisher’s exact tests, Wilcoxon rank sum tests, and an unpaired t-test were used to compare variables between (CD) and (CL) groups, and to compare variables between acceptable and unacceptable impressions. Level of significance was set at 0.05 for all analysis. Within this small sample size, the 2 groups (CD and CL) are significantly similar in relation to most variables. Only TEAR and EVAL were significantly different between CD and CL, and VOID was significantly different between acceptable and not acceptable impression groups. Conclusions: Within the limitations of this study, marginal tearing statistically affected the acceptance of impressions made using the cordless procedure.Master of Scienc
Education: tests of whether it enhances productivity or merely conveys information on individual productivity in the labour market
No full textDeposited with permission of the author. © 2001 Dr. Christopher Anthony Ryan.Human capital and screening theories of the role of education in the labour market have similar predictions about individual behaviour and labour market outcomes. This makes it difficult to test between the theories. Nevertheless, the task of doing so is important since the social return to education is likely to be small unless education adds to productivity as human capital theory, but not screening theory, assumes. Education may only convey information about likely individual productivity under screening. It serves this function because individual productivity is difficult for employers to observe. In fact, there is very little evidence from existing tests of the theories that education does not add to productivity. However, few of the tests that have been undertaken between the theories are convincing. The three empirical chapters of this thesis contain tests of some aspects of the theories
The Student Movement Volume 107 Issue 12: Revisiting The Dream : Students Celebrate MLK Day
No full textHUMANS
Andrews Gaming Club, Interviewed by: Grace No
Meet Gio Lee, Interviewed by: Nora Martin
New Year, Happier Me, Gloria Oh
ARTS & ENTERTAINMENT
Art @ AU: Harrigan\u27s Gallery, Ysabelle Fernando
Currently: The Way of Water, Solana Campbell
Ode to 2022, Amelia Stefanescu
Where Do I Find God - Part I, Anonymous
NEWS
Honoring Martin Luther King Jr.\u27s Legacy, Brendan Oh
Is America Safe?: First Grader Shoots Teacher, Julia Randall
A House Divided: Current Issues Within the School of Architecture and Interior Design, Student Movement Editorial Staff
IDEAS
Harry & Meghan: Unpacking Royal Pains, Gabriela Francisco
A New Space for Creativity and Reaching Across Disciplinary Boundaries: The Inspiration Center, Peter Lyons, Anthony Bosman, Martin Hanna, Ryan Hayes, and Karin Thompson
PULSE
Our Food: Can They Cook It?, Melissa Moore
Should We Have Bible Classes in the Core Curriculum?, Wambui Karanja
What Comes First is a Question, Part II, Desmond H. Murray
LAST WORD
College in the Rearview Mirror, Scott Moncrieffhttps://digitalcommons.andrews.edu/sm-107/1011/thumbnail.jp
Report on ISS O2 Production, Gas Supply & Partial Pressure Management
No full textBellevue, WashingtonRyan N. Schaezler, The Boeing Company, USAAnthony J. Cook, The Boeing Company, USAThe 45th International Conference on Environmental Systems was held in Bellevue, Washington, USA on 12 July 2015 through 16 July 2015.Oxygen is used on International Space Station (ISS) for metabolic support and denitrogenation procedures prior to Extra-Vehicular Activities. Nitrogen is used to maintain total pressure and account for losses associated with leakage and operational losses. Oxygen and nitrogen have been supplied by various visiting vehicles such as the Progress and Shuttle in addition to the on-orbit oxygen production capability. Starting in 2014, new high pressure oxygen/nitrogen tanks are available to launch on commercial cargo vehicles and will replace the high pressure gas source that Shuttle used to provide. To maintain a habitable atmosphere the oxygen and nitrogen partial pressures are controlled between upper and lower bounds. The full range of the allowable partial pressures along with the increased ISS cabin volume are utilized as a buffer allowing days to pass between oxygen production or direct addition of oxygen and nitrogen to the atmosphere from reserves. This paper summarizes the amount of gas supplied and produced from all of the sources and describes past experience of managing partial pressures along with the range of management options available to the ISS
Cross Elasticity of Supply: As Big a Secret in Canada as It Is in the U.S.
No full textIn a prior study, the author determined that cross elasticity of supply is rarely discussed in intermediate microeconomics, and industrial organization textbooks used in U. S. universities. He did, however, find that the American judicial system has increasingly relied upon the concept in defining product markets. In the present paper, the author examines cross elasticity of supply in economics textbooks in Canadian universities. Similar to his prior study, the author found virtually no mention of the concept in the Canadian textbooks. However, unlike the prior study, he found no appreciable reliance upon cross elasticity of supply in defining product markets by Canadian courts. Though perplexed over its lack of academic discussion, the author is encouraged by the deference paid to cross elasticity of supply by American courts.
Ocean acidification: linking science to management solutions using the Great Barrier Reef as a case study
No full textAbstract not availableRebecca Albright, Kenneth R.N. Anthony, Mark Baird, Roger Beeden, Maria Byrne, Catherine Collier, Sophie Dove, Katharina Fabricius, Ove Hoegh-Guldberg, Ryan P. Kelly, Janice Lough, Mathieu Mongin, Philip L. Munday, Rachel J. Pears, Bayden D. Russell, Bronte Tilbrook, Eva Aba
An investigation of forecasting behaviour
No full textDeposited with permission of the author. © 2002 Anthony Michael Ryan.To manage an uncertain future relevant societal groups, such as government and corporate sectors, utilise economic forecasts to help plan future strategies. Many vital decisions are based on economic forecasts. Economists have traditionally been the professionals employed as economic forecasting experts. The dominant paradigm for present day forecasting is the "rational expectations theory", which assumes that a forecaster is capable of making optimal use all of the available information. The field of psychology offers a different, yet complementary, approach to the topic of economic forecasting. The aim of the current study was to research mental processes and behaviours of individuals participating in a forecasting task. The role of the following psychological variables within economic prediction behaviour was assessed: (1) task complexity, (2) decision making style, (3) the anchoring and adjustment heuristic, (4) the framing effect, and (5) personal feelings about the task content. All of these variables were hypothesised to have a direct influence on prediction behaviour. In addition, task complexity and decision making style were assumed to moderate the influence of the other psychological variables. A conceptual framework was designed to depict the assumed relationships. (For complete abstract open document
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