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Parametric Linear Dynamic Logic
TLDR
The main technical contribution is a translation of PLDL formulas into non-deterministic Buchi word automata of exponential size via alternating automata, which yields a PSPACE model checking algorithm and a realizability algorithm with doubly-exponential running time.
What are Strategies in Delay Games? Borel Determinacy for Games with Lookahead
TLDR
Determinacy of delay games with Borel winning conditions, infinite-duration two-player games in which one player may delay her moves to obtain a lookahead on her opponent's moves, is proved and different notions of universal strategies for both players are introduced.
Finite-state Strategies in Delay Games
TLDR
This work presents a very general framework for computing finite-state strategies in delay games: they exist for all winning conditions that are recognized by automata with acceptance conditions that satisfy a certain aggregation property.
Team Semantics for the Specification and Verification of Hyperproperties
TLDR
This work develops team semantics for Linear Temporal Logic to express hyperproperties, which have recently been identified as a key concept in the verification of information flow properties, and shows that LTL under team semantics is a viable alternative to HyperLTL.
Down the Borel hierarchy: Solving Muller games via safety games
We transform a Muller game with n vertices into a safety game with ( n ! ) 3 vertices whose solution allows us to determine the winning regions of the Muller game and to compute a finite-state
Cost-Parity and Cost-Streett Games
TLDR
Two winning conditions, cost-parity and cost-Streett, which require bounds on the cost between requests and their responses are introduced and it is shown that the first player has positional winning strategies and that determining the winner lies in NP intersection Co-NP.
How Much Lookahead is Needed to Win Infinite Games?
TLDR
Solving delay games with reachability conditions is shown to be PSPACE-complete by giving an exponential time algorithm and an exponential upper bound on the necessary lookahead and showing EXPTIME-hardness of the solution problem and tight exponential lower bounds on the lookahead.
The Keys to Decidable HyperLTL Satisfiability: Small Models or Very Simple Formulas
HyperLTL, the extension of Linear Temporal Logic by trace quantifiers, is a uniform framework for expressing information flow policies by relating multiple traces of a security-critical system.
Easy to Win, Hard to Master: Optimal Strategies in Parity Games with Costs
TLDR
It is shown that the characteristics of parity games with costs are vastly different when asking for strategies realizing the minimal such bound, and that playing optimally is as hard as winning, both in terms of complexity and memory.
Playing Muller Games in a Hurry
TLDR
A sound criterion is presented that stops a play after at most 3^n moves, where n is the size of the arena, which improves the bound (n!+1)^n obtained by McNaughton and the bound n!-1 derived from a reduction to parity games.
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