66 research outputs found
Using an Ellipsoid Model to Track and Predict the Evolution and Propagation of Coronal Mass Ejections
We present a method for tracking and predicting the propagation and evolution
of coronal mass ejections (CMEs) using the imagers on the STEREO and SOHO
satellites. By empirically modeling the material between the inner core and
leading edge of a CME as an expanding, outward propagating ellipsoid, we track
its evolution in three-dimensional space. Though more complex empirical CME
models have been developed, we examine the accuracy of this relatively simple
geometric model, which incorporates relatively few physical assumptions,
including i) a constant propagation angle and ii) an azimuthally symmetric
structure. Testing our ellipsoid model developed herein on three separate CMEs,
we find that it is an effective tool for predicting the arrival of density
enhancements and the duration of each event near 1 AU. For each CME studied,
the trends in the trajectory, as well as the radial and transverse expansion
are studied from 0 to ~.3 AU to create predictions at 1 AU with an average
accuracy of 2.9 hours.Comment: 18 pages, 11 figure
Soviet Urban Politics and Comparative Urban Theory
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67464/2/10.1177_009539977200400304.pd
Four simultaneous component models for the analysis of multivariate time series from more than one subject to model intraindividual and interindividual differences
three-way analysis, exploratory longitudinal analysis,
Intellectual and Emotional Development and School Adjustment in Preterm Children at 6 and 7 Years of Age. Continuation of a Follow-Up Study
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