3,751 research outputs found
On Objective Measures of Rule Surprisingness
Most of the literature argues that surprisingness is an inherently subjective aspect of the discovered knowledge, which cannot be measured in objective terms. This paper departs from this view, and it has a twofold goal: (1) showing that it is indeed possible to define objective (rather than subjective) measures of discovered rule surprisingness; (2) proposing new ideas and methods for defining objective rule surprisingness measures
Investigating Fatigue Performance on the Foamed Asphalt Specimens Generated Using Different Foam Properties
An evaluation of fatigue resistance for foamed asphalt mixture is very demanding since the binder is not continuously distributed on the aggregate surface and this mixtures contains water, the content of which dramatically affects the mechanical properties. This paper discusses the results of laboratory fatigue testingon the foamed asphalt mixtures in which the specimens are generated using three different foamed bitumen properties. Foamed bitumen as the binder was produced at three different foaming water content (FWC) at a temperature of 180oC using a 70/100 pen. The aggregates were mechanically mixed with foamed bitumen using a Hobart mixer. The resulting mixtures were then compacted using a gyratory compactor to generatespecimen with diameter of 100 mm. The specimens were fatigue tested at various stress levels at a temperature of 20oC following a curing period of 3 days at 40oC. Overall, fatigue performance of foamed asphalt can be identified based upon both stress and strain for mixtures produced at FWC 1%, 5%, and 10%
Susceptibilities near the QCD (tri)critical point
Based on the proper-time renormalization group approach, the scalar and the
quark number susceptibilities in the vicinity of possible critical end points
of the hadronic phase diagram are investigated in the two-flavor quark-meson
model. After discussing the quark-mass dependence of the location of such
points, the critical behavior of the in-medium meson masses and quark number
density are calculated. The universality classes of the end points are
determined by calculating the critical exponents of the susceptibilities. In
order to numerically estimate the influence of fluctuations we compare all
quantities with results from a mean-field approximation. It is concluded that
the region in the phase diagram where the susceptibilities are enhanced is more
compressed around the critical end point if fluctuations are included.Comment: 14 pages, 19 figures; v3 typos and minor changes, references adde
VLA Limits for Intermediate Mass Black Holes in Three Globular Clusters
The observational evidence for central black holes in globular clusters has
been argued extensively, and their existence has important consequences for
both the formation and evolution of the cluster. Most of the evidence comes
from dynamical arguments, but the interpretation is difficult, given the short
relaxation times and old ages of the clusters. One of the most robust
signatures for the existence of a black hole is radio and/or X-ray emission. We
observed three globular clusters, NGC6093 (M80), NGC6266 (M62), and NGC7078
(M15), with the VLA in the A and C configuration with a 3-sigma noise of 36, 36
and 25 microJy, respectively. We find no statistically-significant evidence for
radio emission from the central region for any of the three clusters. NGC6266
shows a 2-sigma detection. It is difficult to infer a mass from these upper
limits due to uncertainty about the central gas density, accretion rate, and
accretion model.Comment: 5 pages, accepted for publication in the Astronomical Journa
With a little help from my goals : integrating intergoal facilitation with the theory of planned behaviour to predict physical activity
Reproduced with permission from British Journal of Health Psychology © The British Psychological Society 2010.Peer reviewedPostprin
Recommendations for riparian ecosystem management based on the general frame defined in EUFORGEN and results from EUROPOP
International audienc
Nest use is influenced by the positions of nests and drinkers in aviaries
The influence of the nest location and the placement of nipple drinkers on nest use by laying hens in a commercial aviary was assessed. Twenty pens in a laying hen house were equipped with the same commercial aviary system, but the pens differed in the nest location and the placement of nipple drinkers. Nests were placed along the walls in 10 pens, and nipple drinkers were installed in front of the nests in 5 of these pens. The other 10 pens were equipped with nests placed on a tier within the aviary (integrated nests). Nipple drinkers were installed in front of the nests in 5 of these pens. A total of 225 Lohmann Selected Leghorns were housed per pen. The hens were offered 4 nests per pen: 2 facing the service corridor of the laying hen house and 2 facing the outdoor area. The numbers of nest eggs and mislaid eggs were counted daily per pen. At 25, 36, and 43 wk of age, the nest platforms were videotaped and the behavior of laying hens in front of the nests was analyzed. The nest location affected the stationary and locomotive behaviors in front of the nests. Hens in front of the integrated nests and the nests with drinkers displayed more stationary behaviors than hens in front of wall-placed nests or nests without drinkers. No difference in the number of nest eggs could be detected, but the integration of the nests inside the aviary led to a more even distribution of hens while nest searching. In the pens with wall-placed nests, significantly more hens laid eggs in the nests at the wall near the service corridor than at the wall near the outdoor area. Due to this imbalance, crowding in front of the preferred nests occurred and pushing and agonistic interactions on the nest platforms were significantly more frequent. Placement of nipple drinkers in front of nests had no effect on the number of eggs laid in those nest
Hereditary hydrocephalus internus in a laboratory strain of golden hamsters (Mesocricetus auratus)
Golden hamsters of one common laboratory strain had a high incidence of hydrocephalus internus. When a severity score of hydrocephalus was used, a major autosomal recessive locus could be identified. However, when a binary score (hydrocephalus, no hydrocephalus) was used, no such major locus could be detected and results of test matings were not consistent with Mendelian inheritance. Golden hamsters with severe forms of hydrocephalus had a dorsally compressed and ventrally intact hippocampus. Implications for the behavior and well-being of affected hamsters are unknown but researchers using this strain should be aware of the likely presence of hydrocephalu
A photometric and kinematic study of the stars and interstellar medium in the central two kpc of NGC 3379
HST images of NGC 3379 show that the V and I luminosity profiles in the inner
13 arcsec of this E1 galaxy are represented by two different components: a
stellar bulge following a Sersic Law with exponent n = 2.36, and a central core
(r < 0.7 arcsec) with a characteristic "cuspy" profile. Subtraction of the
underlying stellar component represented by the fitted Sersic profile revealed
the presence of a small (r ~ 105 pc) dust disk of about 150 solar masses,
oriented at PA = 125 degrees and inclined ~ 77 degrees with respect to the line
of sight. The same absorption structure is detected in the color-index (V-I)
image. The stellar rotation in the inner 20 arcsec is well represented by a
parametric planar disk model, inclined ~ 26 degrees relative to the plane of
the sky, and apparent major axis along PA ~ 67 degrees. The gas velocity curves
in the inner 5 arcsec show a steep gradient, indicating that the gas rotates
much faster than the stars, although in the same direction. The velocity field
of the gaseous system, however, is not consistent with the simple model of
Keplerian rotation sustained by the large (7 x 10E9 solar masses within a
radius of ~ 90 pc) central mass implied by the maximum velocity observed, but
the available data precludes a more detailed analysis.Comment: 23 pages, LaTeX(aaspp4.sty), 9 figures included. Figs. 1 and 5 are
colour plates. Accepted for publication in The Astrophysical Journal (part 1
Planetary nebulae in the elliptical galaxy NGC 821: kinematics and distance determination
Using a slitless spectroscopy method with the 8.2 m Subaru telescope and its
FOCAS Cassegrain spectrograph, we have increased the number of planetary nebula
(PN) detections and PN velocity measurements in the flattened elliptical galaxy
NGC 821. A comparison with the detections reported previously by the Planetary
Nebula Spectrograph (PN.S) group indicates that we have confirmed most of their
detections. The velocities measured by the two groups, using different
telescopes, spectrographs and slitless techniques, are in good agreement. We
have built a combined sample of 167 PNs and have confirmed the keplerian
decline of the line-of-sight velocity dispersion reported previously. We also
confirm misaligned rotation from the combined sample. A dark matter halo may
exist around this galaxy, but it is not needed to keep the PN velocities below
the local escape velocity as calculated from the visible mass. We have measured
the m(5007) magnitudes of 145 PNs and produced a statistically complete sample
of 40 PNs in NGC 821. The resulting PN luminosity function (PNLF) was used to
estimate a distance modulus of 31.4 mag, equivalent to 19 Mpc. We also
estimated the PN formation rate. NGC 821 becomes the most distant galaxy with a
PNLF distance determination. The PNLF distance modulus is smaller than the
surface brightness fluctuation (SBF) distance modulus by 0.4 mag. Our kinematic
information permits to rule out the idea that a shorter PNLF distance could be
produced by the contamination of the PNLF by background galaxies with emission
lines redshifted into the on-band filter transmission curve.Comment: Accepted for publication in ApJ; 16 figure
- …
