2,252 research outputs found
Recommended from our members
M2U-net: Effective and efficient retinal vessel segmentation for real-world applications
In this paper, we present a novel neural network architecture for retinal vessel segmentation that improves over the state of the art on two benchmark datasets, is the first to run in real time on high resolution images, and its small memory and processing requirements make it deployable in mobile and embedded systems. The M2U-Net has a new encoder-decoder architecture that is inspired by the U-Net. It adds pretrained components of MobileNetV2 in the encoder part and novel contractive bottleneck blocks in the decoder part that, combined with bilinear upsampling, drastically reduce the parameter count to 0.55M compared to 31.03M in the original U-Net. We have evaluated its performance against a wide body of previously published results on three public datasets. On two of them, the M2U-Net achieves new state-of-the-art performance by a considerable margin. When implemented on a GPU, our method is the first to achieve real-time inference speeds on high-resolution fundus images. We also implemented our proposed network on an ARM-based embedded system where it segments images in between 0.6 and 15 sec, depending on the resolution. Thus, the M2U-Net enables a number of applications of retinal vessel structure extraction, such as early diagnosis of eye diseases, retinal biometric authentication systems, and robot assisted microsurgery
Ab initio prediction of magnetically dead layers in freestanding -Ce(111)
It is well known that the surface of nonmagnetic -Ce is magnetically
ordered, i.e., -like. One then might conjecture, in agreement with
previous theoretical predictions, that the -Ce may also exhibit at its
surfaces even more strongly enhanced -like magnetic ordering.
Nonetheless, our result shows that the (111)-surfaces of magnetic -Ce
are neither spin nor orbitally polarized, i.e., -like. Therefore, we
predict, in contrast to the nonmagnetic -phase which tends to produce
magnetically ordered -like thin layers at its free surfaces, the
magnetic -phase has a tendency to form -like dead layers. This
study, which explains the suppressed (promoted) surface magnetic moments of
-Ce (-Ce), shows that how nanoscale can reverse physical
properties by going from bulk to the surface in isostructural - and
-phases of cerium. We predict using our freestanding surface results
that a typical unreactive and non-diffusive substrate can dramatically
influence the magnetic surface of cerium thin films in contrast to most of the
uncorrelated thin films and strongly correlated transition metals. Our result
implies that magnetic surface moments of -Ce(111) can be suddenly
disappeared by increasing lattice mismatch at the interface of a typical
unreactive and non-diffusive substrate with cerium overlayers.Comment: 6 pages, 3 figures, 1 tabl
Attenuating Consumer Reactance to Threatening Messages: The Moderating Role of Construal Level
While many persuasive communications tend to be perceived as increasing consumer choice, others, such as public service announcements, more or less forcefully restrict that choice. This research examines the effects of threats to freedom on receptivity to message information, as a function of the level of construal at which the message is processed. The findings indicate that consumers are more open to high threat message information at high (vs. low) levels of construal, and this pattern holds when construal level is manipulated via message wording (study one) or is non-consciously primed prior to message exposure (study two). Also, the results point to the level of detail at which the message is considered, and the resulting use of persuasion knowledge, as the underlying reason for this pattern of results (study three). Specifically, at high levels of detail (i.e. low construal) there is a greater use of persuasion knowledge and lower information receptivity in face of high threat to freedom messages. At low level of detail (high construal), by contrast, persuasion knowledge use is lower and receptivity to information in freedom threatening messages higher
Electronic, dielectric and optical properties of two dimensional and bulk ice: a multi-scale simulation study
The intercalated water into nanopores exhibits anomalous properties such as
ultralow dielectric constant.~Multi-scale modeling and simulations are used to
investigate the dielectric properties of various crystalline two-dimensional
ices and bulk ices. Although, the structural properties of two-dimensional
(2D-) ices have been extensively studied, much less is known about their
electronic and optical properties. First, by using density functional theory
(DFT) and density functional perturbation theory (DFPT), we calculate the key
electronic, optical and dielectric properties of 2D-ices. Performing DFPT
calculations, both the ionic and electronic contributions of the dielectric
constant are computed. The in-plane electronic dielectric constant is found to
be larger than the out-of-plane dielectric constant for all the studied
2D-ices. The in-plane dielectric constant of the electronic response is found
to be isotropic for all the studied ices. Secondly, we determined the dipolar
dielectric constant of 2D-ices using molecular dynamics simulations (MDS) at
finite temperature. The total out-of-plane dielectric constant is found to be
larger than 2 for all the studied 2D-ices. Within the framework of the
random-phase approximation (RPA), the absorption energy ranges for 2D-ices are
found to be in the ultraviolet spectra. For the comparison purposes, we also
elucidate the electronic, dielectric and optical properties of four crystalline
ices (ice VIII, ice XI, ice Ic and ice Ih) and bulk water
- …