3,597 research outputs found
Data-Driven Sparse Structure Selection for Deep Neural Networks
Deep convolutional neural networks have liberated its extraordinary power on
various tasks. However, it is still very challenging to deploy state-of-the-art
models into real-world applications due to their high computational complexity.
How can we design a compact and effective network without massive experiments
and expert knowledge? In this paper, we propose a simple and effective
framework to learn and prune deep models in an end-to-end manner. In our
framework, a new type of parameter -- scaling factor is first introduced to
scale the outputs of specific structures, such as neurons, groups or residual
blocks. Then we add sparsity regularizations on these factors, and solve this
optimization problem by a modified stochastic Accelerated Proximal Gradient
(APG) method. By forcing some of the factors to zero, we can safely remove the
corresponding structures, thus prune the unimportant parts of a CNN. Comparing
with other structure selection methods that may need thousands of trials or
iterative fine-tuning, our method is trained fully end-to-end in one training
pass without bells and whistles. We evaluate our method, Sparse Structure
Selection with several state-of-the-art CNNs, and demonstrate very promising
results with adaptive depth and width selection.Comment: ECCV Camera ready versio
Inch by inch: Making our Gardens Grow
Why bring gardens to early education programs? School garden success has a long history, but this success has been found primarily in elementary schools (Blair 2009). Yet child care centers are typically open year-round and therefore are better prepared to enjoy the full bounty that gardens may provide.
Gardening with young children isnât new (McFarland 2005), but a small national âfarm to child care movementâ that supports garden programs is growing (Berkenkamp and Mader 2012).
Unfortunately, many teachers are not familiar with gardening and plant science (Blair 2009). The novelty of gardening may be one of the obstacles in bringing gardens to the child care environment. Other obstacles can include concerns about working with children in messy outdoor settings and engaging in strenuous labor.
So why do it? What are the benefits for young children
The Fermi Gamma-Ray Haze from Dark Matter Annihilations and Anisotropic Diffusion
Recent full-sky maps of the Galaxy from the Fermi Gamma-Ray Space Telescope
have revealed a diffuse component of emission towards the Galactic center and
extending up to roughly +/-50 degrees in latitude. This Fermi "haze" is the
inverse Compton emission generated by the same electrons which generate the
microwave synchrotron haze at WMAP wavelengths. The gamma-ray haze has two
distinct characteristics: the spectrum is significantly harder than emission
elsewhere in the Galaxy and the morphology is elongated in latitude with
respect to longitude with an axis ratio ~2. If these electrons are generated
through annihilations of dark matter particles in the Galactic halo, this
morphology is difficult to realize with a standard spherical halo and isotropic
cosmic-ray diffusion. However, we show that anisotropic diffusion along ordered
magnetic field lines towards the center of the Galaxy coupled with a prolate
dark matter halo can easily yield the required morphology without making
unrealistic assumptions about diffusion parameters. Furthermore, a Sommerfeld
enhancement to the self annihilation cross-section of ~30 yields a good fit to
the morphology, amplitude, and spectrum of both the gamma-ray and microwave
haze. The model is also consistent with local cosmic-ray measurements as well
as CMB constraints.Comment: 14 pages, 9 figures; submitted to Ap
A high resolution line survey of IRC+10216 with Herschel. First results: Detection of warm silicon dicarbide SiC2
We present the first results of a high-spectral-resolution survey of the
carbon-rich evolved star IRC+10216 that was carried out with the HIFI
spectrometer onboard Herschel. This survey covers all HIFI bands, with a
spectral range from 488 to 1901GHz. In this letter we focus on the band-1b
spectrum, in a spectral range 554.5-636.5GHz, where we identified 130 spectral
features with intensities above 0.03 K and a signal-to-noise ratio >5. Detected
lines arise from HCN, SiO, SiS, CS, CO, metal-bearing species and,
surprisingly, silicon dicarbide (SiC2). We identified 55 SiC2 transitions
involving energy levels between 300 and 900 K. By analysing these rotational
lines, we conclude that SiC2 is produced in the inner dust formation zone, with
an abundance of ~2x10^-7 relative to molecular hydrogen. These SiC2 lines have
been observed for the first time in space and have been used to derive an SiC2
rotational temperature of ~204 K and a source-averaged column density of
~6.4x10^15 cm^-2. Furthermore, the high quality of the HIFI data set was used
to improve the spectroscopic rotational constants of SiC2.Comment: A&A HIFI Special Issue, 201
Cost implications of new treatments for advanced colorectal cancer: Cost-effectiveness of CRC Treatment
Since 1996, six new drugs have been introduced for the treatment of metastatic colorectal cancer. While promising, these drugs are frequently given in the palliative, and are much more expensive than older treatments. The objective of this study is to measure the cost implications of treatment with sequential regimens that include chemotherapy and/or monoclonal antibodies
Evidence for Quasi-isotropic Magnetic Fields from Hinode Quiet Sun Observations
Some recent investigations of spectropolarimetric observations of the Zeeman
effect in the Fe I lines at 630 nm carried out with the Hinode solar space
telescope have concluded that the strength of the magnetic field vector in the
internetwork regions of the quiet Sun is in the hG regime and that its
inclination is predominantly horizontal. We critically reconsider the analysis
of such observations and carry out a complete Bayesian analysis with the aim of
extracting as much information as possible from them, including error bars. We
apply the recently developed BayesME code that carries out a complete Bayesian
inference for Milne-Eddington atmospheres. The sampling of the posterior
distribution function is obtained with a Markov Chain Monte Carlo scheme and
the marginal distributions are analyzed in detail. The Kullback-Leibler
divergence is used to study the extent to which the observations introduce new
information in the inference process resulting in sufficiently constrained
parameters. Our analysis clearly shows that only upper limits to the magnetic
field strength can be inferred with fields in the kG regime completely
discarded. Furthermore, the noise level present in the analyzed Hinode
observations induces a substantial loss of information for constraining the
azimuth of the magnetic field. Concerning the inclination of the field, we
demonstrate that some information is available to constrain it for those pixels
with the largest polarimetric signal. The results also point out that the field
in pixels with small polarimetric signals can be nicely reproduced in terms of
a quasi-isotropic distribution.Comment: 13 pages, 10 figures, accepted for publication in Ap
nIFTy galaxy cluster simulations â II. Radiative models
We have simulated the formation of a massive galaxy cluster (M = 1.110) in a CDM universe using
10 different codes (RAMSES, 2 incarnations of AREPO and 7 of GADGET), modeling
hydrodynamics with full radiative subgrid physics. These codes include
Smoothed-Particle Hydrodynamics (SPH), spanning traditional and advanced SPH
schemes, adaptive mesh and moving mesh codes. Our goal is to study the
consistency between simulated clusters modeled with different radiative
physical implementations - such as cooling, star formation and AGN feedback. We
compare images of the cluster at , global properties such as mass, and
radial profiles of various dynamical and thermodynamical quantities. We find
that, with respect to non-radiative simulations, dark matter is more centrally
concentrated, the extent not simply depending on the presence/absence of AGN
feedback. The scatter in global quantities is substantially higher than for
non-radiative runs. Intriguingly, adding radiative physics seems to have washed
away the marked code-based differences present in the entropy profile seen for
non-radiative simulations in Sembolini et al. (2015): radiative physics +
classic SPH can produce entropy cores. Furthermore, the inclusion/absence of
AGN feedback is not the dividing line -as in the case of describing the stellar
content- for whether a code produces an unrealistic temperature inversion and a
falling central entropy profile. However, AGN feedback does strongly affect the
overall stellar distribution, limiting the effect of overcooling and reducing
sensibly the stellar fraction.Comment: 20 pages, 13 figures, submitted to MNRA
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