1,650 research outputs found
SO(3) Yang-Mills theory on the lattice
We numerically investigate the phase structure of pure SO(3) LGT at zero and
non-zero temperature in the presence of a Z2 blind monopole chemical potential.
The physical meaning of the different phases, a possible symmetry breaking
mechanism as well as the existence of an order parameter for the finite
temperature phase transition are discussed.Comment: 3 pages, 2 figures LaTeX file. Uses espcrc2 style and amssymb
package. Talk given at Lattice2002(nonzerot), Boston. Corrected version with
one added referenc
SO(3) vs. SU(2) Yang-Mills theory on the lattice: an investigation at non-zero temperature
The adjoint SU(2) lattice gauge theory in 3+1 dimensions with the Wilson
plaquette action modified by a Z(2) monopole suppression term is reinvestigated
with special emphasis on the existence of a finite-temperature phase transition
decoupling from the well-known bulk transitions.Comment: 13 pages, 9 figures. Based on contributions to CONFINEMENT 2003 and
Lattice2003(topology). To be published in Proceedings of CONFINEMENT 2003,
Tokyo, Japa
The neutron star in Cassiopeia A: equation of state, superfluidity, and Joule heating
The thermomagnetic evolution of the young neutron star in Cassiopea A is
studied by considering fast neutrino emission processes. In particular, we
consider neutron star models obtained from the equation of state computed in
the framework of the Brueckner-Bethe-Goldstone many-body theory and variational
methods, and models obtained with the Akmal-Pandharipande-Ravenhall equation of
state. It is shown that it is possible to explain a fast cooling regime as the
one observed in the neutron star in Cassiopea A if the Joule heating produced
by dissipation of the small-scale magnetic field in the crust is taken into
account. We thus argue that it is difficult to put severe constraints on the
superfluid gap if the Joule heating is considered.Comment: 4 pages, 2 figures, to appear on A&A Letter
Chaoticity and Dissipation of Nuclear Collective Motion in a Classical Model
We analyze the behavior of a gas of classical particles moving in a
two-dimensional "nuclear" billiard whose multipole-deformed walls undergo
periodic shape oscillations. We demonstrate that a single particle Hamiltonian
containing coupling terms between the particles' motion and the collective
coordinate induces a chaotic dynamics for any multipolarity, independently on
the geometry of the billiard. The absence of coupling terms allows us to
recover qualitatively the "wall formula" predictions. We also discuss the
dissipative behavior of the wall motion and its relation with the
order-to-chaos transition in the dynamics of the microscopic degrees of
freedom.Comment: LateX, 11 pages, 7 figures available on request, to appear in the
Proceedings of XXXIV Winter Meeting on Nuclear Physics, Bormio 22-27 January,
199
Reduction of False Positives in Intrusion Detection Based on Extreme Learning Machine with Situation Awareness
Protecting computer networks from intrusions is more important than ever for our privacy, economy, and national security. Seemingly a month does not pass without news of a major data breach involving sensitive personal identity, financial, medical, trade secret, or national security data. Democratic processes can now be potentially compromised through breaches of electronic voting systems. As ever more devices, including medical machines, automobiles, and control systems for critical infrastructure are increasingly networked, human life is also more at risk from cyber-attacks. Research into Intrusion Detection Systems (IDSs) began several decades ago and IDSs are still a mainstay of computer and network protection and continue to evolve. However, detecting previously unseen, or zero-day, threats is still an elusive goal. Many commercial IDS deployments still use misuse detection based on known threat signatures. Systems utilizing anomaly detection have shown great promise to detect previously unseen threats in academic research. But their success has been limited in large part due to the excessive number of false positives that they produce.
This research demonstrates that false positives can be better minimized, while maintaining detection accuracy, by combining Extreme Learning Machine (ELM) and Hidden Markov Models (HMM) as classifiers within the context of a situation awareness framework. This research was performed using the University of New South Wales - Network Based 2015 (UNSW-NB15) data set which is more representative of contemporary cyber-attack and normal network traffic than older data sets typically used in IDS research. It is shown that this approach provides better results than either HMM or ELM alone and with a lower False Positive Rate (FPR) than other comparable approaches that also used the UNSW-NB15 data set
Chaos vs. Linear Instability in the Vlasov Equation: A Fractal Analysis Characterization
In this work we discuss the most recent results concerning the Vlasov
dynamics inside the spinodal region. The chaotic behaviour which follows an
initial regular evolution is characterized through the calculation of the
fractal dimension of the distribution of the final modes excited. The ambiguous
role of the largest Lyapunov exponent for unstable systems is also critically
reviewed.Comment: 10 pages, RevTeX, 4 figures not included but available upon reques
ANFORE E CERAMICHE COMUNI E DA FUOCO DA THERMAE HIMERAEAE (SICILIA) E DAL SUO HINTERLAND
This report, part of a wider project involving the ancient landscapes of Himera and Thermae, presents the
archaeological and archaeometric results on Late Roman amphorae and coarse/cooking wares from Termini Imerese.
The aim is also to illustrate the distribution of the same types of Roman pottery in the hinterland of Thermae, where the
Dept. of Cultural Heritage of Palermo University has carried out intensive surveys (from 1982, published from 1988
until 2009). A good documentation of African amphorae, coarse/cooking wares, produced both in Byzacena and
Zeugitana, and also local amphorae and coarse/cooking wares and Pantellerian ware, have been found both in
Thermae and in the hinterland, together with African red slip ware and lamps (not illustrated)
- …