9,740 research outputs found
An automatic deep learning approach for coronary artery calcium segmentation
Coronary artery calcium (CAC) is a significant marker of atherosclerosis and
cardiovascular events. In this work we present a system for the automatic
quantification of calcium score in ECG-triggered non-contrast enhanced cardiac
computed tomography (CT) images. The proposed system uses a supervised deep
learning algorithm, i.e. convolutional neural network (CNN) for the
segmentation and classification of candidate lesions as coronary or not,
previously extracted in the region of the heart using a cardiac atlas. We
trained our network with 45 CT volumes; 18 volumes were used to validate the
model and 56 to test it. Individual lesions were detected with a sensitivity of
91.24%, a specificity of 95.37% and a positive predicted value (PPV) of 90.5%;
comparing calcium score obtained by the system and calcium score manually
evaluated by an expert operator, a Pearson coefficient of 0.983 was obtained. A
high agreement (Cohen's k = 0.879) between manual and automatic risk prediction
was also observed. These results demonstrated that convolutional neural
networks can be effectively applied for the automatic segmentation and
classification of coronary calcifications
An adaptive stigmergy-based system for evaluating technological indicator dynamics in the context of smart specialization
Regional innovation is more and more considered an important enabler of
welfare. It is no coincidence that the European Commission has started looking
at regional peculiarities and dynamics, in order to focus Research and
Innovation Strategies for Smart Specialization towards effective investment
policies. In this context, this work aims to support policy makers in the
analysis of innovation-relevant trends. We exploit a European database of the
regional patent application to determine the dynamics of a set of technological
innovation indicators. For this purpose, we design and develop a software
system for assessing unfolding trends in such indicators. In contrast with
conventional knowledge-based design, our approach is biologically-inspired and
based on self-organization of information. This means that a functional
structure, called track, appears and stays spontaneous at runtime when local
dynamism in data occurs. A further prototyping of tracks allows a better
distinction of the critical phenomena during unfolding events, with a better
assessment of the progressing levels. The proposed mechanism works if
structural parameters are correctly tuned for the given historical context.
Determining such correct parameters is not a simple task since different
indicators may have different dynamics. For this purpose, we adopt an
adaptation mechanism based on differential evolution. The study includes the
problem statement and its characterization in the literature, as well as the
proposed solving approach, experimental setting and results.Comment: mail: [email protected]
Continuous variable cloning via network of parametric gates
We propose an experimental scheme for the cloning machine of continuous
quantum variables through a network of parametric amplifiers working as
input-output four-port gates.Comment: 4 pages, 2 figures. To appear on Phys. Rev. Let
Entangling macroscopic diamonds at room temperature: Bounds on the continuous-spontaneous-localization parameters
A recent experiment [K. C. Lee et al., Science 334, 1253 (2011)] succeeded in
detecting entanglement between two macroscopic specks of diamonds, separated by
a macroscopic distance, at room temperature. This impressive results is a
further confirmation of the validity of quantum theory in (at least parts of)
the mesoscopic and macroscopic domain, and poses a challenge to collapse
models, which predict a violation of the quantum superposition principle, which
is the bigger the larger the system. We analyze the experiment in the light of
such models. We will show that the bounds placed by experimental data are
weaker than those coming from matter-wave interferometry and
non-interferometric tests of collapse models.Comment: 7 pages, 3 figures, v2: close to the published version, LaTe
The three-body recombination of a condensed Bose gas near a Feshbach resonance
In this paper, we study the three-body recombination rate of a homogeneous
dilute Bose gas with a Feshbach resonance at zero temperature. The ground state
and excitations of this system are obtained. The three-body recombination in
the ground state is due to the break-up of an atom pair in the quantum
depletion and the formation of a molecule by an atom from the broken pair and
an atom from the condensate. The rate of this process is in good agreement with
the experiment on Na in a wide range of magnetic fields.Comment: 10 pages, 2 figures, to be published in Phys. Rev.
Perencanaan Suksesi Pada Perusahaan Keluarga Di Kota Denpasar
The main objective of this study was to determine the succession planning a family business in the city of Denpasar . This research was conducted at the family business in Denpasar Data were analyzed qualitatively and quantitatively using a Likert scale and to determine the factors that influence succession planning in family business were analyzed with multiple linear regression using SPSS . The results found that succession planning in family business in the city of Denpasar has done well based on considerations mean value of 4:07 per cent . Values and characteristics successor positive effect on corporate succession planning families business in the city of Denpasar
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