# AMUSE: a minimally-unsatisfiable subformula extractor

@article{Oh2004AMUSEAM, title={AMUSE: a minimally-unsatisfiable subformula extractor}, author={Yoonna Oh and M. Mneimneh and Zaher S. Andraus and K. Sakallah and I. Markov}, journal={Proceedings. 41st Design Automation Conference, 2004.}, year={2004}, pages={518-523} }

This paper describes a new algorithm for extracting unsatisfiable subformulas from a given unsatisfiable CNF formula. Such unsatisfiable "cores" can be very helpful in diagnosing the causes of infeasibility in large systems. Our algorithm is unique in that it adapts the "learning process" of a modern SAT solver to identify unsatisfiable subformulas rather than search for satisfying assignments. Compared to existing approaches, this method can be viewed as a bottom-up core extraction procedure… Expand

#### 126 Citations

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A depth-firstsearch algorithm and a breadth-first-search algorithm are proposed to compute minimal unsatisfiable cores in SMT, adopting different searching strategy. Expand

Finding Unsatisfiable Subformulas with Stochastic Method

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- IDEAL
- 2007

A resolution-based stochastic local search algorithm that directly constructs the resolution sequences for proving unsatisfiability with a local search procedure, and then extracts small unsatisfiable subformulas from the refutation traces is proposed. Expand

A Heuristic Local Search Algorithm for Unsatisfiable Cores Extraction

- Mathematics, Computer Science
- ICCSA
- 2007

A heuristic-based local search algorithm is proposed to derive unsatisfiable cores by directly constructs the resolution sequence for proving unsatisfiability with a local search procedure, and then extracts small unsatisfiability cores from the sequence. Expand

On Finding All Minimally Unsatisfiable Subformulas

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- 2005

A novel technique is developed for extracting all MUSes of a CNF formula, tightly integrat ing the authors' implementation with a modern SAT solver and discussing ways in which ideas from both could be combined to improve further. Expand

MUP: a minimal unsatisfiability prover

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- Proceedings of the ASP-DAC 2005. Asia and South Pacific Design Automation Conference, 2005.
- 2005

After establishing the unsatisfiability of a SAT instance encoding a typical design task, there is a practical need to identify its minimal unsatisfiable subsets, which pinpoint the reasons for the… Expand

Finding First-Order Minimal Unsatisfiable Cores with a Heuristic Depth-First-Search Algorithm

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- IDEAL
- 2011

DFS-Finder is presented, which finds minimal unsatisfiable cores in first-order logic, adopting a heuristic depth-first-search strategy and demonstrating the effectiveness of this approach on a very extensive test of SMT-LIB benchmarks. Expand

Tracking Unsatisfiable Subformulas from Reduced Refutation Proof

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This paper presents the definitions of refutation proof and refutation parsing graph, and proposes a resolution based local search algorithm to track unsatisfiable subformulas according to the reduced refutationProof of a formula. Expand

From Max-SAT to Min-UNSAT : Insights and Applications

- 2005

This report describes a strong connection between maximum satisfiability and minimally-unsatisfiable subfor-mulas of any constraint system, as well as techniques for exploiting it. Focusing on CNF… Expand

On Improving MUS Extraction Algorithms

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The first algorithm is optimal in its class, meaning that it requires the smallest number of calls to a SAT solver, and the resulting algorithms achieve significant performance gains with respect to state of the art MUS extraction algorithms. Expand

On Computing Minimum Unsatisfiable Cores

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- SAT
- 2004

As part of the process of generating unsatisfiable proofs, one is also interested in unsatisfiable subformulas of the original formula, also known as unsatisfiable cores, which may be very useful in AI problems where identifying the minimum core is crucial for correcting the minimum amount of inconsistent information. Expand

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