12,493 research outputs found
Serious interface design for dental health: Wiimote-based tangible interaction for school children
This paper describes a camera-based approach towards creating a tangible interface for serious games. We introduce our game for dental health targeted at school children which implements the Nintendo WiiMote as infrared camera. Paired with a gesture-recognition system, this combination allows us to apply real-world items as input devices. Thereby, the game tries to address different aspects of dental hygiene along with the improvement of children's motor skills. In our focus group test, we found that tangible interfaces offer great potential for educational purposes and can be used to engage kids in a playful learning process by addressing their childlike curiosity and fostering implicit learning
gamma-ray DBSCAN: a clustering algorithm applied to Fermi-LAT gamma-ray data. I. Detection performances with real and simulated data
The Density Based Spatial Clustering of Applications with Noise (DBSCAN) is a
topometric algorithm used to cluster spatial data that are affected by
background noise. For the first time, we propose the use of this method for the
detection of sources in gamma-ray astrophysical images obtained from the
Fermi-LAT data, where each point corresponds to the arrival direction of a
photon. We investigate the detection performance of the gamma-ray DBSCAN in
terms of detection efficiency and rejection of spurious clusters, using a
parametric approach, and exploring a large volume of the gamma-ray DBSCAN
parameter space. By means of simulated data we statistically characterize the
gamma-ray DBSCAN, finding signatures that differentiate purely random fields,
from fields with sources. We define a significance level for the detected
clusters, and we successfully test this significance with our simulated data.
We apply the method to real data, and we find an excellent agreement with the
results obtained with simulated data. We find that the gamma-ray DBSCAN can be
successfully used in the detection of clusters in gamma-ray data. The
significance returned by our algorithm is strongly correlated with that
provided by the Maximum Likelihood analysis with standard Fermi-LAT software,
and can be used to safely remove spurious clusters. The positional accuracy of
the reconstructed cluster centroid compares to that returned by standard
Maximum Likelihood analysis, allowing to look for astrophysical counterparts in
narrow regions, minimizing the chance probability in the counterpart
association. We find that gamma-ray DBSCAN is a powerful tool in the detection
of clusters in gamma-ray data, this method can be used both to look for
point-like sources, and extended sources, and can be potentially applied to any
astrophysical field related with detection of clusters in data.Comment: Accepted for publication in A&
Learning an Interactive Segmentation System
Many successful applications of computer vision to image or video
manipulation are interactive by nature. However, parameters of such systems are
often trained neglecting the user. Traditionally, interactive systems have been
treated in the same manner as their fully automatic counterparts. Their
performance is evaluated by computing the accuracy of their solutions under
some fixed set of user interactions. This paper proposes a new evaluation and
learning method which brings the user in the loop. It is based on the use of an
active robot user - a simulated model of a human user. We show how this
approach can be used to evaluate and learn parameters of state-of-the-art
interactive segmentation systems. We also show how simulated user models can be
integrated into the popular max-margin method for parameter learning and
propose an algorithm to solve the resulting optimisation problem.Comment: 11 pages, 7 figures, 4 table
Characterizing and Improving Stability in Neural Style Transfer
Recent progress in style transfer on images has focused on improving the
quality of stylized images and speed of methods. However, real-time methods are
highly unstable resulting in visible flickering when applied to videos. In this
work we characterize the instability of these methods by examining the solution
set of the style transfer objective. We show that the trace of the Gram matrix
representing style is inversely related to the stability of the method. Then,
we present a recurrent convolutional network for real-time video style transfer
which incorporates a temporal consistency loss and overcomes the instability of
prior methods. Our networks can be applied at any resolution, do not re- quire
optical flow at test time, and produce high quality, temporally consistent
stylized videos in real-time
Molecular simulation of 2-dimensional microphase separation of single-component homopolymers grafted onto a planar substrate
The structural phase behavior of polymer brushes, single-component linear
homopolymers grafted onto a planar substrate, is studied using the molecular
Monte Carlo method in 3 dimensions. When simulation parameters of the system
are set in regions of macrophase separation of solution for the corresponding
non-grafted homopolymers, the grafted polymers also prefer segregation.
However, macrophase separation is disallowed due to the spatially-fixed
grafting points of the polymers. Such constraints on the grafting are similar
to connecting points between blocks of non-grafted diblock copolymers at the
microphase separation in the melt state. This results in "microphase
separation" of the homopolymer brush in the lateral direction of the substrate.
Here we extensively search the parameter space and reveal various lateral
domain patterns that are similar to those found in diblock copolymer melts at
microphase separation.Comment: 6 pages, 5 figures, accepted for publication in EP
CLD-shaped Brushstrokes in Non-Photorealistic Rendering
Rendering techniques based on a random grid can be improved by adapting
brushstrokes to the shape of different areas of the original picture. In this
paper, the concept of Coherence Length Diagram is applied to determine the
adaptive brushstrokes, in order to simulate an impressionist painting. Some
examples are provided to instance the proposed algorithm.Comment: Keywords: Image processing, Non-photorealistic processing,
Image-based rendering Coherence Length Diagra
Models of MOS and SOS devices
Quarterly report describes progress in three programs: dc sputtering machine for aluminum and aluminum alloys; two dimensional computer modeling of MOS transistors; and development of computer techniques for calculating redistribution diffusion of dopants in silicon on sapphire films
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