7,851 research outputs found
FCN-rLSTM: Deep Spatio-Temporal Neural Networks for Vehicle Counting in City Cameras
In this paper, we develop deep spatio-temporal neural networks to
sequentially count vehicles from low quality videos captured by city cameras
(citycams). Citycam videos have low resolution, low frame rate, high occlusion
and large perspective, making most existing methods lose their efficacy. To
overcome limitations of existing methods and incorporate the temporal
information of traffic video, we design a novel FCN-rLSTM network to jointly
estimate vehicle density and vehicle count by connecting fully convolutional
neural networks (FCN) with long short term memory networks (LSTM) in a residual
learning fashion. Such design leverages the strengths of FCN for pixel-level
prediction and the strengths of LSTM for learning complex temporal dynamics.
The residual learning connection reformulates the vehicle count regression as
learning residual functions with reference to the sum of densities in each
frame, which significantly accelerates the training of networks. To preserve
feature map resolution, we propose a Hyper-Atrous combination to integrate
atrous convolution in FCN and combine feature maps of different convolution
layers. FCN-rLSTM enables refined feature representation and a novel end-to-end
trainable mapping from pixels to vehicle count. We extensively evaluated the
proposed method on different counting tasks with three datasets, with
experimental results demonstrating their effectiveness and robustness. In
particular, FCN-rLSTM reduces the mean absolute error (MAE) from 5.31 to 4.21
on TRANCOS, and reduces the MAE from 2.74 to 1.53 on WebCamT. Training process
is accelerated by 5 times on average.Comment: Accepted by International Conference on Computer Vision (ICCV), 201
Understanding Traffic Density from Large-Scale Web Camera Data
Understanding traffic density from large-scale web camera (webcam) videos is
a challenging problem because such videos have low spatial and temporal
resolution, high occlusion and large perspective. To deeply understand traffic
density, we explore both deep learning based and optimization based methods. To
avoid individual vehicle detection and tracking, both methods map the image
into vehicle density map, one based on rank constrained regression and the
other one based on fully convolution networks (FCN). The regression based
method learns different weights for different blocks in the image to increase
freedom degrees of weights and embed perspective information. The FCN based
method jointly estimates vehicle density map and vehicle count with a residual
learning framework to perform end-to-end dense prediction, allowing arbitrary
image resolution, and adapting to different vehicle scales and perspectives. We
analyze and compare both methods, and get insights from optimization based
method to improve deep model. Since existing datasets do not cover all the
challenges in our work, we collected and labelled a large-scale traffic video
dataset, containing 60 million frames from 212 webcams. Both methods are
extensively evaluated and compared on different counting tasks and datasets.
FCN based method significantly reduces the mean absolute error from 10.99 to
5.31 on the public dataset TRANCOS compared with the state-of-the-art baseline.Comment: Accepted by CVPR 2017. Preprint version was uploaded on
http://welcome.isr.tecnico.ulisboa.pt/publications/understanding-traffic-density-from-large-scale-web-camera-data
The rotational shear layer inside the early red-giant star KIC 4448777
We present the asteroseismic study of the early red-giant star KIC 4448777,
complementing and integrating a previous work (Di Mauro et al. 2016), aimed at
characterizing the dynamics of its interior by analyzing the overall set of
data collected by the {\it Kepler} satellite during the four years of its first
nominal mission. We adopted the Bayesian inference code DIAMOND (Corsaro \& De
Ridder 2014) for the peak bagging analysis and asteroseismic splitting
inversion methods to derive the internal rotational profile of the star. The
detection of new splittings of mixed modes, more concentrated in the very inner
part of the helium core, allowed us to reconstruct the angular velocity profile
deeper into the interior of the star and to disentangle the details better than
in Paper I: the helium core rotates almost rigidly about 6 times faster than
the convective envelope, while part of the hydrogen shell seems to rotate at a
constant velocity about 1.15 times lower than the He core. In particular, we
studied the internal shear layer between the fast-rotating radiative interior
and the slow convective zone and we found that it lies partially inside the
hydrogen shell above and extends across the core-envelope
boundary. Finally, we theoretically explored the possibility for the future to
sound the convective envelope in the red-giant stars and we concluded that the
inversion of a set of splittings with only low-harmonic degree , even
supposing a very large number of modes, will not allow to resolve the
rotational profile of this region in detail.Comment: accepted for publication on Ap
Generation and detection of bound entanglement
We propose a method for the experimental generation of two different families
of bound entangled states of three qubits. Our method is based on the explicit
construction of a quantum network that produces a purification of the desired
state. We also suggest a route for the experimental detection of bound
entanglement, by employing a witness operator plus a test of the positivity of
the partial transposes
Oral Health-Related Quality of Life in Brazilian Patients Wearing Three Types of Lower Dentures: Psychosocial and Clinical Aspects
The purpose of this study was to evaluate the oral health-related Quality of Life (QoL) of patients with edentulous lower jaws rehabilitated with conventional or implant-supported dentures. In the quest for greater QoL, especially among the elderly, it is important to evaluate how the use of dentures impacts physical and emotional well-being. Brazilian health care policy makers should be informed of the advantages of rehabilitation with implant-supported dentures. A cohort of 78 edentulous seniors was divided into three groups of 26 according to denture type: Conventional (CD), Implant-Supported Overdenture (IOD) and Fixed-Implant Prosthesis (FIP). To evaluate QoL, clinical and sociodemographic information was collected and the OHIP-20 questionnaire was administered, using a 5-point frequency scale, including a “don’t know” option. Chewing and pronunciation were less impacted in FIP and IOD than in CD (p=0.013 and p=0.027, respectively), while patients in the CD group reported more adaptation difficulties (p=0.006) and more frequent avoidance of hard-to-chew foods (p=0.032). The majority reported no interference of dentures with appearance and social life, regardless of denture type. Depending on the patient’s biological and financial circumstances, implant-supported dentures is the form of rehabilitation of edentulism providing the greatest improvement in QoL. The reported limitations and difficulties had no significant impact on satisfaction and QoL
Homotopy Type Theory in Lean
We discuss the homotopy type theory library in the Lean proof assistant. The
library is especially geared toward synthetic homotopy theory. Of particular
interest is the use of just a few primitive notions of higher inductive types,
namely quotients and truncations, and the use of cubical methods.Comment: 17 pages, accepted for ITP 201
Remarks on Charged Vortices in the Maxwell-Chern-Simons Model
We study vortex-like configuration in Maxwell-Chern-Simons Electrodynamics.
Attention is paid to the similarity it shares with the Nielsen-Olesen solutions
at large distances. A magnetic symmetry between a point-like and an
azimuthal-like current in this framework is also pointed out. Furthermore, we
address the issue of a neutral and spinless particle interacting with a charged
vortex, and obtain that the Aharonov-Casher-type phase depends upon mass and
distance parameters.Comment: New refs. added. Version accepted for publication in Phys. Lett.
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