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Evidence for Two Distinct Morphological Classes of Gamma-Ray Bursts from their Short Timescale Variability
We have analyzed the 241 bursts for which peak counts \C exist in the
publicly available Burst and Transient Source Experiment (BATSE) catalog.
Introducing peak counts in 1024 ms as a measure of burst brightness \B and
the ratio of peak counts in 64 and 1024 ms as a measure of short timescale
variability \V, we find a statistically significant correlation between the
brightness and the short timescale variability of \g-ray bursts. The bursts
which are smoother on short timescales are both faint and bright, while the
bursts which are variable on short timescales are faint only, suggesting the
existence of two distinct morphological classes of bursts.Comment: 9 pages + 2 Postscript figures available upon request; LATEX v. 2.0
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Value-based argumentation frameworks as neural-symbolic learning systems
While neural networks have been successfully used in a number of machine learning applications, logical languages have been the standard for the representation of argumentative reasoning. In this paper, we establish a relationship between neural networks and argumentation networks, combining reasoning and learning in the same argumentation framework. We do so by presenting a new neural argumentation algorithm, responsible for translating argumentation networks into standard neural networks. We then show a correspondence between the two networks. The algorithm works not only for acyclic argumentation networks, but also for circular networks, and it enables the accrual of arguments through learning as well as the parallel computation of arguments
Coherent vibrations of submicron spherical gold shells in a photonic crystal
Coherent acoustic radial oscillations of thin spherical gold shells of
submicron diameter excited by an ultrashort optical pulse are observed in the
form of pronounced modulations of the transient reflectivity on a subnanosecond
time scale. Strong acousto-optical coupling in a photonic crystal enhances the
modulation of the transient reflectivity up to 4%. The frequency of these
oscillations is demonstrated to be in good agreement with Lamb theory of free
gold shells.Comment: Error in Eqs.2 and 3 corrected; Tabl. I corrected; Fig.1 revised; a
model that explains the dependence of the oscillation amplitude of the
transient reflectivity with wavelength adde
Oxidative Heck desymmetrisation of 2,2-disubstituted cyclopentene-1,3-diones
Oxidative Heck couplings have been successfully developed for 2,2-disubstituted cyclopentene-1,3-diones. The direct coupling onto the 2,2-disubstituted cyclopentene-1,3-dione core provides a novel expedient way of enantioselectively desymmetrising all-carbon quaternary centres
Repetition of contaminating question types when children and youths with intellectual disabilities are interviewed
Background The present study examined the effects of repeating questions in interviews investigating the possible sexual abuse of children and youths who had a variety of intellectual disabilities. We predicted that the repetition of option-posing and suggestive questions would lead the suspected victims to change their responses, making it difficult to understand what actually happened. Inconsistency can be a key factor when assessing the reliability of witnesses. Materials Case files and transcripts of investigative interviews with 33 children and youths who had a variety of intellectual disabilities were obtained from prosecutors in Sweden. The interviews involved 25 females and 9 males whose chronological ages were between 5.4 and 23.7 years when interviewed (M = 13.2 years). Results Six per cent of the questions were repeated at least once. The repetition of focused questions raised doubts about the reports because the interviewees changed their answers 40% of the time. Conclusions Regardless of the witnesses' abilities, it is important to obtain reports that are as accurate and complete as possible in investigative interviews. Because this was a field study, we did not know which responses were accurate, but repetitions of potentially contaminating questions frequently led the interviewees to contradict their earlier answers. This means that the interviewers' behaviour diminished the usefulness of the witnesses' testimony
Genetic Algorithm for Epidemic Mitigation by Removing Relationships
Min-SEIS-Cluster is an optimization problem which aims at minimizing the
infection spreading in networks. In this problem, nodes can be susceptible to
an infection, exposed to an infection, or infectious. One of the main features
of this problem is the fact that nodes have different dynamics when interacting
with other nodes from the same community. Thus, the problem is characterized by
distinct probabilities of infecting nodes from both the same and from different
communities. This paper presents a new genetic algorithm that solves the
Min-SEIS-Cluster problem. This genetic algorithm surpassed the current
heuristic of this problem significantly, reducing the number of infected nodes
during the simulation of the epidemics. The results therefore suggest that our
new genetic algorithm is the state-of-the-art heuristic to solve this problem.Comment: GECCO '17 - Proceedings of the Genetic and Evolutionary Computation
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