15 research outputs found
06351 Summary -- Methods for Modelling Software Systems (MMOSS)
We survey the key objectives and the structure of this Dagstuhl seminar,
and discuss common themes that emerged
06351 Abstracts Collection -- Methods for Modelling Software Systems (MMOSS)
From 27.08.06 to 01.09.06, the Dagstuhl Seminar 06351 ``Methods for Modelling Software Systems (MMOSS)\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl.
During the seminar, several participants presented their current
research, and ongoing work and open problems were discussed. Abstracts of
the presentations given during the seminar as well as abstracts of
seminar results and ideas are put together in this paper. The first section
describes the seminar topics and goals in general.
Links to extended abstracts or full papers are provided, if available
Formal Dependability Engineering with MIOA
In this paper, we introduce MIOA, a stochastic process algebra-like specification language with datatypes, as well as a logic intSPDL, and its model checking algorithms. MIOA, which stands for Markovian input/output automata language, is an extension of Lynch's input/automata with Markovian timed transitions.MIOA can serve both as a fully fledged ``stand-alone'' specification language and the semantic model for the architectural dependability modelling and evaluation language Arcade. The logic intSPDL is an extension of the stochastic logic SPDL, to deal with the specialties of MIOA. intSPDL in the context of Arcade can be seen as the semantic model of abstract and complex dependability measures that can be defined in the Arcade framework. We define syntax and semantics of both MIOA and intSPDL, and show examples of applying MIOA and intSPDL in the realm of dependability modelling with Arcade
Dagstuhl News January - December 2006
"Dagstuhl News" is a publication edited especially for the members of the Foundation "Informatikzentrum Schloss Dagstuhl" to thank them for their support. The News give a summary of the scientific work being done in Dagstuhl. Each Dagstuhl Seminar is presented by a small abstract describing the contents and scientific highlights of the seminar as well as the perspectives or challenges of the research topic
Enterprise Modelling using Algebraic Graph Transformation - Extended Version
An analysis of today's situation at Credit Suisse has shown severe problems, because it is based on current best practices and ad-hoc modelling techniques to handle important aspects of security, risk and compliance. Based on this analysis we propose in this paper a new enterprise model which allows the construction, integration, transformation and evaluation of different organizational models in a big decentralized organization like Credit Suisse. The main idea of the new model framework is to provide small decentralized models and intra-model evaluation techniques to handle services, processes and rules separately for the business and IT universe on one hand and for human-centric and machine-centric concepts on the other hand. Furthermore, the new framework provides inter-modelling techniques based on algebraic graph transformation to establish the connection between different kinds of models and to allow integration of the decentralized models. In order to check for security, risk and compliance in a suitable way, our models and techniques are based on different kinds of formal methods. In this paper, we show that algebraic graph transformation techniques are useful not only for intra-modelling - using graph grammars for visual languages and graph constraints for requirements - but also for inter-modelling - using triple graph grammars for model transformation and integration. Altogether, we present the overall idea of our new model framework and show how to solve specific problems concerning intra- and inter-modelling as first steps. This should give evidence that our framework can also handle important other requirements for enterprise modelling in a big decentralized organization like Credit Suisse
Foundations for Behavioural Model Elaboration Using Modal Transition Systems
Modal Transition Systems (MTS) are an extension of Labelled Transition Systems
(LTS) that have been shown to be useful to reason about system behaviour in the
context of partial information. MTSs distinguish between required, proscribed
and unknown behaviour and come equipped with a notion of refinement that supports
incremental modelling where unknown behaviour is iteratively elaborated
into required or proscribed behaviour.
A particularly useful notion in the context of software and requirements engineering
is that of āmergeā. Merging two consistent models is a process that should
result in a minimal common refinement of both models where consistency is defined
as the existence of one common refinement. One of the current limitations
of MTS merging is that a complete and correct algorithm for merging has not
been developed. Hence, an engineer attempting to merge partial descriptions may
be prevented to do so by overconstrained algorithms or algorithms that introduce
behaviour that does not follow from the partial descriptions being merged. In
this thesis we study the problems of consistency and merge for the existing MTSs
semantics - strong and weak semantics - and provide a complete characterization
of MTS consistency as well as a complete and correct algorithm for MTS merging
using these semantics.
Strong and weak semantics require MTS models to have the same communicating
alphabet, the latter allowing the use of a distinguished unobservable action. In
this work we show that the requirement of fixing the alphabet for MTS semantics
and the treatment of observable actions are limiting if MTSs are to support
incremental elaboration of partial behaviour models. We present a novel observational
semantics for MTS, branching alphabet semantics, inspired by branching
LTS equivalence, which supports the elaboration of model behaviour including
the extension of the alphabet of the system to describe behaviour aspects that
previously had not been taken into account. Furthermore, we show that some
unintuitive refinements allowed by weak semantics are avoided, and prove a number
of theorems that relate branching refinement with alphabet refinement and
consistency. These theorems, which do not hold for other semantics, support the
argument for considering branching alphabet as a sound semantics to support
behaviour model elaboration