Events at MS Teams

Two optimizations for Zielonka’s recursive algorithm for solving parity games are investigated. The first optimization is partial re-decomposition, in which only the part of the graph containing vertices of SCCs which have 1 or more vertices removed will be re-decomposed. The second optimization is dynamic SCC maintenance, which builds an SCC tree for each SCC …continue reading

It is well known that Peterson’s algorithm for two processes is starvation free. In this talk I study the generalization of Peterson’s algorithm to N>2 processes using tournament trees. In particular, I will show how, contrary to the two processes version, this algorithm is not starvation free if we do not make any fairness assumptions. …continue reading

A “Proof Assistant” is a computer program that allows users to create complete mathematical proofs, interactively with the computer, where the computer checks each small reasoning step. In this way one obtains the utmost guarantee of correctness. I will outline how Proof Assistants work, how they are used to verify mathematical proofs and computer systems. Verifying a proof with a …continue reading

In this presentation we focus on how we envision OIL components to communicate with each other. We define the behaviour of communicating OIL components using a formalism found in literature, namely the FIFO system, and we show how this can be modelled in mCRL2. Also, we show some typical unwanted behaviour in asynchronous communication and …continue reading

Last week, Myrthe Spronck discussed mutual exclusion algorithms when using safe registers. In this week’s talk, I will stick with the topic of mutual exclusion algorithms, but switch back to using atomic registers. I will introduce Dekker’s algorithm for mutual exclusion. According to Dijkstra, this is the first algorithm to solve mutual exclusion between two …continue reading

For my bachelor research project, supervised by Bas Luttik, I set out to verify Aravind’s bounded least recently used (BLRU) algorithm for mutual exclusion using mCRL2. An interesting property of Aravind’s algorithm is that it can ensure mutual exclusion even when the registers used are safe, rather than atomic. In order to verify this property, …continue reading

In this talk, I will discuss McMillan’s algorithm for fully SAT-based unbounded symbolic model checking. The method is based on computing Craig interpolants. In terms of performance, the algorithm is substantially more efficient than BDD-based model checking. I will also explain how we modify McMillan’s algorithm to analyze the backward reachability of initial states from …continue reading