50 research outputs found
Modeling and Analysis of Mixed Synchronous/Asynchronous Systems
Practical safety-critical distributed systems must integrate safety critical and non-critical data in a common platform. Safety critical systems almost always consist of isochronous components that have synchronous or asynchronous interface with other components. Many of these systems also support a mix of synchronous and asynchronous interfaces. This report presents a study on the modeling and analysis of asynchronous, synchronous, and mixed synchronous/asynchronous systems. We build on the SAE Architecture Analysis and Design Language (AADL) to capture architectures for analysis. We present preliminary work targeted to capture mixed low- and high-criticality data, as well as real-time properties in a common Model of Computation (MoC). An abstract, but representative, test specimen system was created as the system to be modeled
Dealing with AADL end-to-end Flow Latency with UML Marte.
The original publication is available from IEEE explore (http://dx.doi.org/10.1109/ICECCS.2008.14)International audienceAADL and MARTE are both modeling formalisms supporting the analysis of real-time embedded systems. We investigate how MARTE, with its Time Model facilities, can be made to represent faithfully AADL periodic/aperiodic tasks communicating through event or data ports, in an approach to end-to-end flow latency analysis
Foundations of Multi-Paradigm Modelling for Cyber-Physical Systems
This open access book coherently gathers well-founded information on the fundamentals of and formalisms for modelling cyber-physical systems (CPS). Highlighting the cross-disciplinary nature of CPS modelling, it also serves as a bridge for anyone entering CPS from related areas of computer science or engineering. Truly complex, engineered systems—known as cyber-physical systems—that integrate physical, software, and network aspects are now on the rise. However, there is no unifying theory nor systematic design methods, techniques or tools for these systems. Individual (mechanical, electrical, network or software) engineering disciplines only offer partial solutions. A technique known as Multi-Paradigm Modelling has recently emerged suggesting to model every part and aspect of a system explicitly, at the most appropriate level(s) of abstraction, using the most appropriate modelling formalism(s), and then weaving the results together to form a representation of the system. If properly applied, it enables, among other global aspects, performance analysis, exhaustive simulation, and verification. This book is the first systematic attempt to bring together these formalisms for anyone starting in the field of CPS who seeks solid modelling foundations and a comprehensive introduction to the distinct existing techniques that are multi-paradigmatic. Though chiefly intended for master and post-graduate level students in computer science and engineering, it can also be used as a reference text for practitioners
Un meta-modèle de composants pour la réalisation d'applications temps-réel flexibles et modulaires
The increase of software complexity along the years has led researchers in the software engineering field to look for approaches for conceiving and designing new systems. For instance, the service-oriented architectures approach is considered nowadays as the most advanced way to develop and integrate fastly modular and flexible applications. One of the software engineering solutions principles is re-usability, and consequently generality, which complicates its appilication in systems where optimizations are often used, like real-time systems. Thus, create real-time systems is expensive, because they must be conceived from scratch. In addition, most real-time systems do not beneficiate of the advantages which comes with software engineering approches, such as modularity and flexibility. This thesis aim to take real time aspects into account on popular and standard SOA solutions, in order to ease the design and development of modular and flexible applications. This will be done by means of a component-based real-time application model, which allows the dynamic reconfiguration of the application architecture. The component model will be an extension to the SCA standard, which integrates quality of service attributs onto the service consumer and provider in order to stablish a real-time specific service level agreement. This model will be executed on the top of a OSGi service platform, the standard de facto for development of modular applications in Java.La croissante complexité du logiciel a mené les chercheurs en génie logiciel à chercher des approcher pour concevoir et projéter des nouveaux systèmes. Par exemple, l'approche des architectures orientées services (SOA) est considérée actuellement comme le moyen le plus avancé pour réaliser et intégrer rapidement des applications modulaires et flexibles. Une des principales préocuppations des solutions en génie logiciel et la réutilisation, et par conséquent, la généralité de la solution, ce qui peut empêcher son application dans des systèmes où des optimisation sont souvent utilisées, tels que les systèmes temps réels. Ainsi, créer un système temps réel est devenu très couteux. De plus, la plupart des systèmes temps réel ne beneficient pas des facilités apportées par le genie logiciel, tels que la modularité et la flexibilité. Le but de cette thèse c'est de prendre en compte ces aspects temps réel dans des solutions populaires et standards SOA pour faciliter la conception et le développement d'applications temps réel flexibles et modulaires. Cela sera fait à l'aide d'un modèle d'applications temps réel orienté composant autorisant des modifications dynamiques dans l'architecture de l'application. Le modèle de composant sera une extension au standard SCA qui intègre des attributs de qualité de service sur le consomateur et le fournisseur de services pour l'établissement d'un accord de niveau de service spécifique au temps réel. Ce modèle sera executé sur une plateforme de services OSGi, le standard de facto pour le developpement d'applications modulaires en Java
Automated Fault Tolerance Augmentation in Model-Driven Engineering for CPS
Cyber-Physical Systems are usually subject to dependability requirements such as safety and reliability constraints. Over the last 50 years, a body of efficient fault-tolerance mechanisms has been devised to handle faults occurring at run-time. However, properly implementing those mechanisms is a time-consuming task that requires a great deal of know-how. In this paper, we propose a general framework which allows system designers to decouple functional and non-functional concerns, and express non- functional properties at design time using domain-specific languages. In the spirit of generative programming, functional models are then automatically “augmented” with dependability mechanisms. Importantly, the real-time behavior of the initial models in terms of sampling times and meeting deadlines is preserved. The practicality of the approach is demonstrated with the automated implementation of one prominent software fault-tolerance pattern, namely N-Version Programming, in the CPAL model-driven engineering workflow
Integration of Quality Attributes in Software Product Line Development
Different
approaches
for
building
modern
software
systems
in
complex
and
open
environments
have
been
proposed
in
the
last
few
years.
Some
efforts
try
to
apply
Software
Product
Line
(SPL)
approach
to
take
advantage
of
the
massive
reuse
for
producing
software
systems
that
share
a
common
set
of
features.
In
general
quality
assurance
is
a
crucial
activity
for
success
in
software
industry,
but
it
is
even
more
important
when
talking
about
Software
Product
Lines
since
the
intensive
reuse
of
assets
makes
the
quality
attributes
(a
measurable
physical
or
abstract
property
of
an
entity)
of
the
assets
to
be
transmitted
to
the
whole
SPL
scope.
However,
despite
the
importance
that
quality
has
in
software
product
line
development,
most
of
the
methodologies
being
applied
in
Software
Product
Line
Development
focus
only
on
managing
the
commonalities
and
variability
within
the
product
line
and
not
giving
support
to
the
non--Âż
functional
requirements
that
the
products
must
fit.
The
main
goal
of
this
master
final
work
is
to introduce
quality
attributes
in
early
stages
of
software
product
line
development
processes
by
means
of
the
definition
of
a
production
plan
that,
on
one
hand,
integrates
quality
as
an
additional
view
for
describing
the
extension
of
the
software
product
line
and,
on
the
other
hand
introduces
the
quality
attributes
as
a
decision
factor
during
product
configuration
and
when
selecting
among
design
alternatives.
Our
approach
has
been
defined
following
the
Model--Âż
Driven
Software
Development
paradigm.
Therefore
all
the
software
artifacts
defined
had
its
correspondent
metamodels
and
the
processes
defined
rely
on
automated
model
transformations.
Finally
in
order
to
illustrate
the
feasibility
of
the
approach
we
have
integrated
the
quality
view
in
an
SPL
example
in
the
context
of
safety
critical
embedded
systems
on
the
automotive
domain.González Huerta, J. (2011). Integration of Quality Attributes in Software Product Line Development. http://hdl.handle.net/10251/15835Archivo delegad