Seminar by Prof. Andrea Bobbio
Integrating Performance Evaluation and Correctness Verification in the Dependent Systems
Prof. Andrea Bobbio
Dipartimento di Informatica
Universita` del Piemonte Orientale "A. Avogadro"
15100 Alessandria (Italy)
Date: Thursday, November 21, 2002
Time: 04:00 PM
Venue: CS-101
Abstract
In Stochastic Models the timing of events is represented by random variables of known distribution. Typical fields of application are in the area of performance and dependability analysis. The obtainable measures are in the form of expected values and distributions. A particular important case is the one in which all the random variables are exponentially distributed and the time behavior of the system is mapped into a continuous time Markov chain. However, distributions with infinite support do not capture the effect of critical deadlines (watchdogs, real-time etc..). In the context of correctness verification the duration of events is assigned by means of non-deterministic intervals, qualified between a minimum and a maximum, but not quantified in probabilistic terms. The analysis, sometimes called functional analysis, solves the problem of conformity to a given specification, the evaluation of the length of feasible behaviors and the verification of reachability properties.
Furthermore models can be based on a discrete state space, on a continuous state space or on a combination of the two (usually referred to a hybrid models).
Our recent research work has tried to gain cross fertilization from the various modeling environments and to explore an unifying language to cast different modelling paradigms in a common framewok. A tool supporting these ideas is under development.
About the Speaker
Prof. Andera Bobbio is visiting the department for six weeks, and is writing a book jointly with Prof. Kishore Trivedi.