148,055 research outputs found
SiZer for time series: A new approach to the analysis of trends
Smoothing methods and SiZer are a useful statistical tool for discovering
statistically significant structure in data. Based on scale space ideas
originally developed in the computer vision literature, SiZer (SIgnificant ZERo
crossing of the derivatives) is a graphical device to assess which observed
features are `really there' and which are just spurious sampling artifacts. In
this paper, we develop SiZer like ideas in time series analysis to address the
important issue of significance of trends. This is not a straightforward
extension, since one data set does not contain the information needed to
distinguish `trend' from `dependence'. A new visualization is proposed, which
shows the statistician the range of trade-offs that are available. Simulation
and real data results illustrate the effectiveness of the method.Comment: Published at http://dx.doi.org/10.1214/07-EJS006 in the Electronic
Journal of Statistics (http://www.i-journals.org/ejs/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Third Interger Resonance Slow Extraction Using RFKO at High Space Charge
A proposal to search for direct {\mu}-->e conversion at Fermilab requires
slow, resonant extraction of an intense proton beam. Large space charge forces
will present challenges, partly due to the substantial betatron tune spread.
The main challenges will be maintaining a uniform spill profile and moderate
losses at the septum. We propose to use "radio frequency knockout" (RFKO) for
fine tuning the extraction. Strategies for the use of the RFKO method will be
discussed here in the context of the Mu2e experiment. The feasibility of this
method has been demonstrated in simulations.Comment: 3 pp. 2nd International Particle Accelerator Conference: IPAC 2011.
4-9 Sep 2011. San Sebastian, Spai
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