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A golden block based self-refining scheme for repetitive patterned wafer inspections
This paper presents a novel technique for detecting possible defects in two-dimensional wafer images with repetitive patterns using prior knowledge. It has a learning ability that is able to create a golden block database from the wafer image itself, modify and refine its content when used in further inspections. The extracted building block is stored as a golden block for the detected pattern. When new wafer images with the same periodical pattern arrives, we do not have to re-calculate its periods and building block. A new building block can be derived directly from the existing golden block after eliminating alignment differences. If the newly derived building block has better quality than the stored golden block, then the golden block is replaced with the new building block. With the proposed algorithm, our implementation shows that a significant amount of processing time is saved. And the storage overhead of golden templates is also reduced significantly by storing golden blocks only
Testing the Empirical Shock Arrival Model using Quadrature Observations
The empirical shock arrival (ESA) model was developed based on quadrature
data from Helios (in-situ) and P-78 (remote-sensing) to predict the Sun-Earth
travel time of coronal mass ejections (CMEs) [Gopalswamy et al. 2005a]. The ESA
model requires earthward CME speed as input, which is not directly measurable
from coronagraphs along the Sun-Earth line. The Solar Terrestrial Relations
Observatory (STEREO) and the Solar and Heliospheric Observatory (SOHO) were in
quadrature during 2010 - 2012, so the speeds of Earth-directed CMEs were
observed with minimal projection effects. We identified a set of 20 full halo
CMEs in the field of view of SOHO that were also observed in quadrature by
STEREO. We used the earthward speed from STEREO measurements as input to the
ESA model and compared the resulting travel times with the observed ones from
L1 monitors. We find that the model predicts the CME travel time within about
7.3 hours, which is similar to the predictions by the ENLIL model. We also find
that CME-CME and CME-coronal hole interaction can lead to large deviations from
model predictions.Comment: 17 pages, 4 figures, 3 table
A Hierarchical Relationship between the Fluence Spectra and CME Kinematics in Large Solar Energetic Particle Events: A Radio Perspective
We report on further evidence that solar energetic particles are organized by
the kinematic properties of coronal mass ejections (CMEs)[1]. In particular, we
focus on the starting frequency of type II bursts, which is related to the
distance from the Sun where the radio emission starts. We find that the three
groups of solar energetic particle (SEP) events known to have distinct values
of CME initial acceleration, also have distinct average starting frequencies of
the associated type II bursts. SEP events with ground level enhancement (GLE)
have the highest starting frequency (107 MHz), while those associated with
filament eruption (FE) in quiescent regions have the lowest starting frequency
(22 MHz); regular SEP events have intermediate starting frequency (81 MHz).
Taking the onset time of type II bursts as the time of shock formation, we
determine the shock formation heights measured from the Sun center. We find
that the shocks form on average closest to the Sun (1.51 Rs) in GLE events,
farthest from the Sun in FE SEP events (5.38 Rs), and at intermediate distances
in regular SEP events (1.72 Rs). Finally, we present the results of a case
study of a CME with high initial acceleration (~3 km s^-2) and a type II radio
burst with high starting frequency (~200 MHz) but associated with a minor SEP
event. We find that the relation between the fluence spectral index and CME
initial acceleration continues to hold even for this minor SEP event.Comment: 11 pages, 7 figures, 1 table, to appear in Journal of Physics:
Conference Series (JPCS), Proceedings of the 16th Annual International
Astrophysics Conference held in Santa Fe, NM, 201
The Peculiar Behavior of Halo Coronal Mass Ejections in Solar Cycle 24
We report on a remarkable finding that the halo coronal mass ejections (CMEs)
in cycle 24 are more abundant than in cycle 23, although the sunspot number in
cycle 24 has dropped by about 40%. We also find that the distribution of
halo-CME source locations is different in cycle 24: the longitude distribution
of halos is much flatter with the number of halos originating at central
meridian distance >/=60 degrees twice as large as that in cycle 23. On the
other hand, the average speed and the associated soft X-ray flare size are the
same in the two cycles, suggesting that the ambient medium into which the CMEs
are ejected is significantly different. We suggest that both the higher
abundance and larger central meridian longitudes of halo CMEs can be explained
as a consequence of the diminished total pressure in the heliosphere in cycle
24 (Gopalswamy et al. 2014). The reduced total pressure allows CMEs expand more
than usual making them appear as halos.Comment: 12 pages, 5 figures, accepted for publication in the Astrophysical
Journal Letters, April 7, 201
Planet formation in highly inclined binaries
We explore planet formation in binary systems around the central star where
the protoplanetary disk plane is highly inclined with respect to the companion
star orbit. This might be the most frequent scenario for binary separations
larger than 40 AU, according to Hale (1994). We focus on planetesimal accretion
and compute average impact velocities in the habitable region and up to 6 AU
from the primary.Comment: Accepted for publication on A&
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