66 research outputs found
Distribution-based bisimulation for labelled Markov processes
In this paper we propose a (sub)distribution-based bisimulation for labelled
Markov processes and compare it with earlier definitions of state and event
bisimulation, which both only compare states. In contrast to those state-based
bisimulations, our distribution bisimulation is weaker, but corresponds more
closely to linear properties. We construct a logic and a metric to describe our
distribution bisimulation and discuss linearity, continuity and compositional
properties.Comment: Accepted by FORMATS 201
Non-thermal emission processes in massive binaries
In this paper, I present a general discussion of several astrophysical
processes likely to play a role in the production of non-thermal emission in
massive stars, with emphasis on massive binaries. Even though the discussion
will start in the radio domain where the non-thermal emission was first
detected, the census of physical processes involved in the non-thermal emission
from massive stars shows that many spectral domains are concerned, from the
radio to the very high energies.
First, the theoretical aspects of the non-thermal emission from early-type
stars will be addressed. The main topics that will be discussed are
respectively the physics of individual stellar winds and their interaction in
binary systems, the acceleration of relativistic electrons, the magnetic field
of massive stars, and finally the non-thermal emission processes relevant to
the case of massive stars. Second, this general qualitative discussion will be
followed by a more quantitative one, devoted to the most probable scenario
where non-thermal radio emitters are massive binaries. I will show how several
stellar, wind and orbital parameters can be combined in order to make some
semi-quantitative predictions on the high-energy counterpart to the non-thermal
emission detected in the radio domain.
These theoretical considerations will be followed by a census of results
obtained so far, and related to this topic... (see paper for full abstract)Comment: 47 pages, 5 postscript figures, accepted for publication in Astronomy
and Astrophysics Review. Astronomy and Astrophysics Review, in pres
Strongly magnetized pulsars: explosive events and evolution
Well before the radio discovery of pulsars offered the first observational
confirmation for their existence (Hewish et al., 1968), it had been suggested
that neutron stars might be endowed with very strong magnetic fields of
-G (Hoyle et al., 1964; Pacini, 1967). It is because of their
magnetic fields that these otherwise small ed inert, cooling dead stars emit
radio pulses and shine in various part of the electromagnetic spectrum. But the
presence of a strong magnetic field has more subtle and sometimes dramatic
consequences: In the last decades of observations indeed, evidence mounted that
it is likely the magnetic field that makes of an isolated neutron star what it
is among the different observational manifestations in which they come. The
contribution of the magnetic field to the energy budget of the neutron star can
be comparable or even exceed the available kinetic energy. The most magnetised
neutron stars in particular, the magnetars, exhibit an amazing assortment of
explosive events, underlining the importance of their magnetic field in their
lives. In this chapter we review the recent observational and theoretical
achievements, which not only confirmed the importance of the magnetic field in
the evolution of neutron stars, but also provide a promising unification scheme
for the different observational manifestations in which they appear. We focus
on the role of their magnetic field as an energy source behind their persistent
emission, but also its critical role in explosive events.Comment: Review commissioned for publication in the White Book of
"NewCompStar" European COST Action MP1304, 43 pages, 8 figure
The genetics of addiction—a translational perspective
Addictions are serious and common psychiatric disorders, and are among the leading contributors to preventable death. This selective review outlines and highlights the need for a multi-method translational approach to genetic studies of these important conditions, including both licit (alcohol, nicotine) and illicit (cannabis, cocaine, opiates) drug addictions and the behavioral addiction of disordered gambling. First, we review existing knowledge from twin studies that indicates both the substantial heritability of substance-specific addictions and the genetic overlap across addiction to different substances. Next, we discuss the limited number of candidate genes which have shown consistent replication, and the implications of emerging genomewide association findings for the genetic architecture of addictions. Finally, we review the utility of extensions to existing methods such as novel phenotyping, including the use of endophenotypes, biomarkers and neuroimaging outcomes; emerging methods for identifying alternative sources of genetic variation and accompanying statistical methodologies to interpret them; the role of gene-environment interplay; and importantly, the potential role of genetic variation in suggesting new alternatives for treatment of addictions
SPLat 2014 : First International Workshop on Software Product Line Analysis Tools
The SPLat 2014 workshop aims to provide a platform for the presentation and positioning of formal analysis tools as used in Software Product Line Engineering for the identification of commonalities and differences of these tools as well as for the inventorying of challenges for their application. SPLat 2014 focuses on the underlying concepts and overall approach, in particular how to mitigate combinatorial explosion
Applications of compactness in the Smyth powerdomain of streams:extended abstract
We show in a uniform setting the crucial role of compactness in the theory of the Smyth powerdomain of streams. The topological notion of compactness is characterized in an order-theoretical manner, involving a notion of bounded sets. We obtain general results on the continuity of operators, and consider applications as diverse as interleaving, hiding and stream programming operators
Denotational models for programming languages : applications of Banach's fixed point theorem
For an abstract programming language both a linear and a branching denotational semantics are developed. The main instrument for the construction of the two models and for the semantical operators involved is the classical Banach Fixed Point Theorem. Via higher-order transformations the various semantical definitions are justified by their characterization as—necessarily unique—fixed points of contractions on a complete metric space. Additionally the Banach Theorem proves itself useful in relating the two models presented
Data-aware design and verification of service compositions with Reo and mCRL2
Service-based systems can be modeled as stand-alone services coordinated by external connectors. Reo is a channelbased coordination language with well-defined semantics that
enables a compositional construction of complex connectors from a set of primitive channels. It has been successfully applied in the area of web service composition specification as well as in business process modeling. In this paper, we present a mapping from Reo to mCRL2, a specification language based on the process algebra ACP, extended with data and time. The mapping enables verification of Reo process models and service compositions using the mCRL2 model checking facilities. The supporting Eclipse Coordination Tools suite provides a user-friendly environment for the
modeling and verification process
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