542 research outputs found
The use of deep learning in image segmentation, classification and detection
Recent years have shown that deep learned neural networks are a valuable tool
in the field of computer vision. This paper addresses the use of two different
kinds of network architectures, namely LeNet and Network in Network (NiN). They
will be compared in terms of both performance and computational efficiency by
addressing the classification and detection problems. In this paper, multiple
databases will be used to test the networks. One of them contains images
depicting burn wounds from pediatric cases, another one contains an extensive
number of art images and other facial databases were used for facial keypoints
detection
High precision framework for Chaos Many-Body Engine
In this paper we present a C# 4.0 high precision framework for simulation of
relativistic many-body systems. In order to benefit from, previously developed,
chaos analysis instruments, all new modules were designed to be integrated with
Chaos Many-Body Engine [1,3]. As a direct application, we used 46 digits
precision for analyzing the Butterfly Effect of the gravitational force in a
specific relativistic nuclear collision toy-model. Trying to investigate the
average Lyapunov Exponent dependency on the incident momentum, an interesting
case of intermittency was noticed. Based on the same framework, other
high-precision simulations are currently in progress (e.g. study on the
possibility of considering, hard to detect, extremely low frequency photons as
one of the dark matter components)
Some phenomenological considerations on the nuclear collisions at high energies
We present some results obtained by applying the chaos theory on the
numerical study of one threedimensional, relativistic, many-body quark system.
The asymptotic freedom property is introduced by employing a harmonic term in
the bi-particle potential. In this context, we used also the outcome of a
semiclassical study, applied to the quark constituents of nucleons. Depending
on the initial temperature parameter, the system can evolve toward an
oscillating or an expansion regime. It is important to notice also a transition
region, characterized by a partial fragmentation (higher degree of order). This
effect can be observed near the critical temperature and is related to the
partial overcoming of the potential barrier (corresponding to the farthest
particles from the system). The degree of fragmentation is defined on the
Shannon entropy basis and using the graphs theory. For analyzing the expansion
tendency of one relativistic many-body system, we employed also the virial
coefficient.Comment: 7 pages, 2 figures, preliminary results presented at Conference of
Physics, Bucharest, 200
Semiclassical study on Proton and Neutron
Starting from the existing semiclassical studies on hydrogenoid atoms, we
propose a similar intuitive exercise for the three-body quark systems
corresponding to protons and neutrons. In the frame of this toy model we try to
explain both the stabilities of proton and neutron with respect to the nuclear
interaction, and the spectrum of nucleonic resonances with J=1/2. Our choice is
motivated also by a good agreement obtained for the up and down quark rest
masses report. Taking into account the deterministic chaotic behavior of
many-body systems, the discussed exercise could be understood as an interesting
particular case of a quantum three-body problem which admits a semiclassical
treatment.Comment: 4 pages, 2 tables, National Conference of Physics (Romania 2005
Implementation of quark confinement, and retarded interactions algorithms for Chaos Many-Body Engine
In Grossu et al. (2012) we presented a Chaos Many-Body Engine (CMBE)
toy-model for chaos analysis of relativistic nuclear collisions at 4.5 A GeV/c
(the SKM 200 collaboration) which was later extended to Cu + Cu collisions at
the maximum BNL energy. Inspired by existing quark billiards, the main goal of
this work was extending CMBE to partons. Thus, we first implemented a
confinement algorithm founded on some intuitive assumptions: 1) the system can
be decomposed into a set of two or three-body quark white clusters; 2) the
bi-particle force is limited to the domain of each cluster; 3) the physical
solution conforms to the minimum potential energy requirement. Color
conservation was also treated as part of the reactions logic module. As an
example of use, we proposed a toy-model for p + p collisions at sqrt(s)=10 GeV
and we compared it with HIJING. Another direction of interest was related to
retarded interactions. Following this purpose, we implemented an Euler retarded
algorithm and we tested it on a simple two-body system with attractive
inverse-square-law force. First results suggest that retarded interactions may
contribute to the Virial theorem anomalies (dark matter) encountered for
gravitational systems (e.g. clusters of galaxies). On the other hand, the time
reverse functionality implemented in CMBE v03 could be used together with
retardation for analyzing the Loschmidt paradox. Regarding the application
design, it is important to mention the code was refactored to SOLID. In this
context, we have also written more than one hundred unit and integration tests,
which represent an important indicator of application logic validity.Comment: Submission to CPC in progres
Code C# for chaos analysis of relativistic many-body systems with reactions
In this work we present a reactions module for "Chaos Many-Body Engine"
(Grossu et al., 2010 [1]). Following our goal of creating a customizable,
object oriented code library, the list of all possible reactions, including the
corresponding properties (particle types, probability, cross-section, particles
lifetime etc.), could be supplied as parameter, using a specific XML input
file. Inspired by the Poincare section, we propose also the "Clusterization
map", as a new intuitive analysis method of many-body systems. For
exemplification, we implemented a numerical toy-model for nuclear relativistic
collisions at 4.5 A GeV/c (the SKM200 collaboration). An encouraging agreement
with experimental data was obtained for momentum, energy, rapidity, and angular
{\pi}- distributions
Intermittency route to chaos for the nuclear billiard - a quantitative study
We extended a previous qualitative study of the intermittent behaviour of a
chaotical nucleonic system, by adding a few quantitative analyses: of the
configuration and kinetic energy spaces, power spectra, Shannon entropies, and
Lyapunov exponents. The system is regarded as a classical "nuclear billiard"
with an oscillating surface of a 2D Woods-Saxon potential well. For the
monopole and dipole vibrational modes we bring new arguments in favour of the
idea that the degree of chaoticity increases when shifting the oscillation
frequency from the adiabatic to the resonance stage of the interaction. The
order-chaos-order-chaos sequence is also thoroughly investigated and we find
that, for the monopole deformation case, an intermittency pattern is again
found. Moreover, coupling between one-nucleon and collective degrees of freedom
is proved to be essential in obtaining chaotic states.Comment: Submitted to Physical Review C, APS REVTEX 4.1, 14 pages, 17
Postscript figure
Intermittency route to chaos for the nuclear billiard - a qualitative study
We analyze on a simple classical billiard system the onset of chaotical
behaviour in different dynamical states. A classical version of the "nuclear
billiard" with a 2D deep Woods-Saxon potential is used. We take into account
the coupling between the single-particle and the collective degrees of freedom
in the presence of dissipation for several vibrational multipolarities. For the
considered oscillation modes an increasing divergence of the nucleonic
trajectories from the adiabatic to the resonance regime was observed. Also, a
peculiar case of intermittency is reached in the vicinity of the resonance, for
the monopole case. We examine the order-to-chaos transition by performing
several types of qualitative analysis including sensitive dependence on the
initial conditions, single-particle phase space maps, fractal dimensions of
Poincare maps and autocorrelation functions.Comment: Submitted to Physical Review C, APS REVTEX 4.1, 12 pages, 15
Postscript figures, title changed, a few references were removed and a few
added, text added on the resonance condition, comments added to the "Fractal
dimensions on the Poincare maps" subsection, the connection of the pkdr
system with the logistic map and the first figure were remove
Study on Proton and Neutron
In this paper we study some phenomenological aspects, related to the proton and neutron stabilities. Working in the frame of the Isgur-Karl quark model, we obtained some encouraging results that could be considered as a premise for future more realistically discussions and analysis
Characterization of Gravitational Waves Signals Using Neural Networks
Gravitational wave astronomy has been already a well-established research
domain for many years. Moreover, after the detection by LIGO/Virgo
collaboration, in 2017, of the first gravitational wave signal emitted during
the collision of a binary neutron star system, that was accompanied by the
detection of other types of signals coming from the same event, multi-messenger
astronomy has claimed its rights more assertively. In this context, it is of
great importance in a gravitational wave experiment to have a rapid mechanism
of alerting about potential gravitational waves events other observatories
capable to detect other types of signals (e.g. in other wavelengths) that are
produce by the same event. In this paper, we present the first progress in the
development of a neural network algorithm trained to recognize and characterize
gravitational wave patterns from signal plus noise data samples. We have
implemented two versions of the algorithm, one that classifies the
gravitational wave signals into 2 classes, and another one that classifies them
into 4 classes, according to the mass ratio of the emitting source. We have
obtained promising results, with 100% training and testing accuracy for the
2-class network and approximately 95% for the 4-class network. We conclude that
the current version of the neural network algorithm demonstrates the ability of
a well-configured and calibrated Bidirectional Long-Short Term Memory software
to classify with very high accuracy and in an extremely short time
gravitational wave signals, even when they are accompanied by noise. Moreover,
the performance obtained with this algorithm qualifies it as a fast method of
data analysis and can be used as a low-latency pipeline for gravitational wave
observatories like the future LISA Mission.Comment: 51 pages, 29 figures. This work was presented at the 13th
International LISA Symposium, 202
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