One of the factors hindering the wide{spread application of qualitative simulation techniques is the diiculty encountered when developing a qualitative model. Analyzing the resulting behavioral description and revising the model in response to this analysis requires a signiicant amount of expertise and is often left up to the modeler. As a result, developing a qualitative model is diicult for u...

In this paper, the one-dimensional Gray–Markel lattice-ladder discrete filter structure is extended to two dimensions (2D). The proposed 2D circuit implementation has minimal number of unit delays. Based on this circuit implementation the corresponding 2D state space realization is derived. The matrices A, b, c and the scalar d of the 2D state space model are presented in generalized closed for...

This paper presents an automatic and simple method for creating refinement condition for UML models. Conditions are fully written in OCL, making it unnecessary the application of mathematical languages which are in general hardly accepted to software engineers. Besides, considering that the state space where OCL conditions are evaluated might be too large (or even infinite), the strategy of mic...

Compliance rules describe regulations, policies and quality constraints business processes must adhere to. Given the large number of rules and their frequency of change, manual compliance checking can become a time-consuming task. Automated compliance checking of process activities and their ordering is an alternative whenever business processes and compliance rules are described in a formal wa...

Symmetry reduction is a promising technique for combatting state space explosion in model checking. The problem of finding the equivalence classes, i.e., the so-called orbits, of states under symmetry is a difficult problem known to be as hard as graph isomorphism. In this paper, we show how we can automatically find the orbits in an actor-based model, called Rebeca, without enforcing any restr...

Real-time systems are often hard to control, due to their complicated structures, quantitative time factors and even unknown delays. We present here PSyHCoS, a tool for analyzing parametric real-time systems specified using the hierarchical modeling language PSTCSP. PSyHCoS supports several algorithms for parameter synthesis and model checking, as well as state space reduction techniques. Its a...

We present a state space exploration method for on-the-fly verification. The method is aimed at systems for which it is possible to define a measure of progress based on the states of the system. The measure of progress makes it possible to delete certain states on-the-fly during state space generation, since these states can never be reached again. This in turn reduces the memory used for stat...

In this paper, a multivariate Markovian traffic model is proposed to characterise H.264/SVC scalable video traces. Parametrisation by a genetic algorithm results in models with a limited state space which accurately capture both the temporal and the inter-layer correlation of the traces. A simulation study further shows that the model is capable of predicting performance of video streaming in v...

The options framework provides a method for reinforcement learning agents to build new high-level skills. However, since options are usually learned in the same state space as the problem the agent is currently solving, they cannot be ported to other similar tasks that have different state spaces. We introduce the notion of learning options in agent-space, the portion of the agent’s sensation t...