1,047 research outputs found
The efficacy of low vision devices for students in specialized schools for students who are blind in Kathmandu Valley, Nepal
In Nepal, children with low vision attend specialized schools for students who are totally blind and are treated as if they were totally blind. This study identified children with low vision and provided low vision devices to them. Of the 22% of the students in the school who had low vision, 78.5% benefited from the devices. Proper devices and counseling improved the quality of life of a significant number of these students. ©2008 AFB, All Rights Reserved
Ariel - Volume 2 Number 2
Editors
Delvyn C. Case, Jr.
Paul M. Fernhoff
News Editors
Richard Bonanno
Daniel B. Gould
Ronald A. Hoffman
Lay-Out Editor
Carol Dolinskas
Sports Editor
James J. Nocon
Contributing Editors
MichaeI J. Blecker
Lin Sey Edwards
Jack Guralnik
W. Cherry Light
Features Editor
Donald A. Bergman
Stephen P. Flynn
Business Manager
Nick Grego
Public Relations
Robin A. Edward
Ariel - Volume 2 Number 7
Editors
Richard J. Bonanno
Robin A. Edwards
Associate Editors
Steven Ager
Stephen Flynn
Shep Dickman
Tom Williams
Lay-out Editor
Eugenia Miller
Contributing Editors
Michael J. Blecker
W. Cherry Light
James J. Nocon
Lynne Porter
Editors Emeritus
Delvyn C. Case, Jr.
Paul M. Fernhof
Formation of diluted IIIâV nitride thin films by N ion implantation
iluted IIIâNââVâËâ alloys were successfully synthesized by nitrogen implantation into GaAs,InP, and AlyGa1âyAs. In all three cases the fundamental band-gap energy for the ion beam synthesized IIIâNââVâËâ alloys was found to decrease with increasing N implantation dose in a manner similar to that observed in epitaxially grownGaNâAs1âx and InNâPâËâalloys. In GaNâAsâËâ the highest value of x (fraction of âactiveâ substitutional N on As sublattice) achieved was 0.006. It was observed that NAs is thermally unstable at temperatures higher than 850â°C. The highest value of x achieved in InNâPâËâ was higher, 0.012, and the NP was found to be stable to at least 850â°C. In addition, the N activation efficiency in implantedInNâPâËâ was at least a factor of 2 higher than that in GaNâAsâËâ under similar processing conditions. AlyGa1âyNâAsâËâ had not been made previously by epitaxial techniques. N implantation was successful in producing AlyGa1âyNâAsâËâalloys. Notably, the band gap of these alloys remains direct, even above the value of y (y>0.44) where the band gap of the host material is indirect.This work was supported by the ââPhotovoltaic Materials
Focus Areaââ in the DOE Center of Excellence for the Synthesis
and Processing of Advanced Materials, Office of Science,
Office of Basic Energy Sciences, Division of Materials
Sciences under U.S. Department of Energy Contract No. DE-ACO3-76SF00098. The work at UCSD was partially supported
by Midwest Research Institute under subcontractor
No. AAD-9-18668-7 from NREL
High fidelity quantum memory via dynamical decoupling: theory and experiment
Quantum information processing requires overcoming decoherence---the loss of
"quantumness" due to the inevitable interaction between the quantum system and
its environment. One approach towards a solution is quantum dynamical
decoupling---a method employing strong and frequent pulses applied to the
qubits. Here we report on the first experimental test of the concatenated
dynamical decoupling (CDD) scheme, which invokes recursively constructed pulse
sequences. Using nuclear magnetic resonance, we demonstrate a near order of
magnitude improvement in the decay time of stored quantum states. In
conjunction with recent results on high fidelity quantum gates using CDD, our
results suggest that quantum dynamical decoupling should be used as a first
layer of defense against decoherence in quantum information processing
implementations, and can be a stand-alone solution in the right parameter
regime.Comment: 6 pages, 3 figures. Published version. This paper was initially
entitled "Quantum gates via concatenated dynamical decoupling: theory and
experiment", by Jacob R. West, Daniel A. Lidar, Bryan H. Fong, Mark F. Gyure,
Xinhua Peng, and Dieter Suter. That original version split into two papers:
http://arxiv.org/abs/1012.3433 (theory only) and the current pape
Ariel - Volume 2 Number 6
Editors
Richard J. Bonanno
Robin A. Edwards
Associate Editors
Steven Ager
Stephen Flynn
Shep Dickman
Tom Williams
Lay-out Editor
Eugenia Miller
Contributing Editors
Michael J. Blecker
W. Cherry Light
James J. Nocon
Lynne Porter
Editors Emeritus
Delvyn C. Case, Jr.
Paul M. Fernhof
Cutting out continuations
In the field of program transformation, one often transforms programs into continuation-passing style to make their flow of control explicit, and then immediately removes the resulting continuations using defunctionalisation to make the programs first-order. In this article, we show how these two transformations can be fused together into a single transformation step that cuts out the need to first introduce and then eliminate continuations. Our approach is calculational, uses standard equational reasoning techniques, and is widely applicable
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