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Page 4093 of Mathematical Reviews Vol. , Issue 2004e [page]

2004 Mathematical Reviews  
results on random unsatisfiable {-Sat instances and approximation algorithms applied to random structures.  ...  Summary: “It is known that random k-Sat instances with at least n(2*1n2) random clauses are unsatisfiable with high probability.  ... 

Backbone Guided Local Search for Maximum Satisfiability

Weixiong Zhang, Ananda Rangan, Moshe Looks
2003 International Joint Conference on Artificial Intelligence  
We call our new algorithm backbone guided Walksat (BGWalksat). On large random SAT and Max-SAT problems as well as instances from the SATLIB, BGWalksat significantly improves Walksat's performance.  ...  Maximum satisfiability (Max-SAT) is more general and more difficult to solve than satisfiability (SAT).  ...  A SAT (Max-SAT) with k literals per clause is denoted as k-SAT (Max-k-SAT). It is known that k-SAT with k greater than two is NP-complete and Max-k-SAT with k being at least two is NPhard [7] .  ... 
dblp:conf/ijcai/ZhangRL03 fatcat:5vonoc7isfekveedk3rbjh6mc4

Using CSP look-back techniques to solve exceptionally hard SAT instances [chapter]

Roberto J. Bayardo, Robert Schrag
1996 Lecture Notes in Computer Science  
We enhance the Tableau SAT algorithm of Crawford and Auton with look-back techniques and evaluate its performance on problems specifically designed to challenge it.  ...  The Random 3-SAT problem space has commonly been used to benchmark SAT algorithms because consistently difficult instances can be found near a region known as the phase transition.  ...  Acknowledgments We wish to thank Jimi Crawford for the Tableau executable and assistance in replicating its behavior.  ... 
doi:10.1007/3-540-61551-2_65 fatcat:lzziqwsq5rdw7e2cj73eftivpq

On the Relative Merits of Simple Local Search Methods for the MAX-SAT Problem [chapter]

Denis Pankratov, Allan Borodin
2010 Lecture Notes in Computer Science  
(SA and MWS) on random 3-CNF and random k-CNF formulas and on benchmarks from MAX-SAT competitions.  ...  In contrast, it is relatively rare that local search algorithms are analyzed with respect to the worst-case approximation ratios.  ...  Finally with regard to random SAT instances we consider Max-k-Sat for k > 3.  ... 
doi:10.1007/978-3-642-14186-7_19 fatcat:rcse7yohjfennnpepnx2vbkofe

Solving satisfiability problems by fluctuations: The dynamics of stochastic local search algorithms

Wolfgang Barthel, Alexander K. Hartmann, Martin Weigt
2003 Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics  
We give numerical and approximate analytical descriptions of the dynamics of such algorithms applied to random satisfiability problems.  ...  Stochastic local search algorithms are frequently used to numerically solve hard combinatorial optimization or decision problems.  ...  Acknowledgments: We are grateful to R. Zecchina for helpful discussions. We also thank R. Monasson and G. Semerjian for communicating their results [23] prior to publication.  ... 
doi:10.1103/physreve.67.066104 pmid:16241301 fatcat:pr4wbesanve5dgk35emkruxuna

Spines of Random Constraint Satisfaction Problems: Definition and Impact on Computational Complexity

Stefan Boettcher, Gabriel Istrate, Allon G. Percus
2004 International Symposium on Artificial Intelligence and Mathematics  
Some of the hardness results for resolution extend to these more powerful proof systems, and in [20] we investigate the extent to which the results of this paper apply to this class of proof systems.  ...  Choose a random constraint from C and apply it on the list of (ordered) variables. We use the notation SAT(C) (instead of CSP(C)) when t=2.  ...  Consider the backtrack tree of the natural DPLL algorithm (that tries to satisfies clauses one at a time) on such a minimally unsatisfiable subformula F .  ... 
dblp:conf/isaim/BoettcherIP04 fatcat:niwxksfhvrauzcne7n7rkztbui

Spines of random constraint satisfaction problems: definition and connection with computational complexity

Gabriel Istrate, Stefan Boettcher, Allon G. Percus
2005 Annals of Mathematics and Artificial Intelligence  
is associated with a 2 Ω(n) resolution complexity (and thus a 2 Ω(n) complexity of DPLL algorithms) on random instances.  ...  We present several further results that add weight to the intuition that random constraint satisfaction problems with a sharp threshold and a continuous spine are "qualitatively similar to random 2-SAT  ...  The k-uniform hypergraph on the 2n nodes (variables and their negations) corresponding to choosing a random instance of SAT (neg) 2 (C) is a random k-uniform hypergraph.  ... 
doi:10.1007/s10472-005-7033-2 fatcat:u43fbvbrajczvmn5wmb4tkwwsm

Spines of Random Constraint Satisfaction Problems: Definition and Connection with Computational Complexity [article]

Gabriel Istrate, Stefan Boettcher, Allon G. Percus
2005 arXiv   pre-print
is associated with a 2^Ω(n) resolution complexity (and thus a 2^Ω(n) complexity of DPLL algorithms) on random instances.  ...  We present several further results that add weight to the intuition that random constraint satisfaction problems with a sharp threshold and a continuous spine are "qualitatively similar to random 2-SAT  ...  The k-uniform hypergraph on the 2n nodes (variables and their negations) corresponding to choosing a random instance of SAT (neg) 2 (C) is a random k-uniform hypergraph.  ... 
arXiv:cs/0503082v1 fatcat:wfqggbv43napzheyyiiwwrdmnu

Backbone Fragility and the Local Search Cost Peak

J. Singer, I. P. Gent, A. Smaill
2000 The Journal of Artificial Intelligence Research  
The local search algorithm WSat is one of the most successful algorithms for solving the satisfiability (SAT) problem.  ...  We make a number of significant contributions to the analysis of WSat on high-cost random instances, using the recently-introduced concept of the backbone of a SAT instance.  ...  We would like to thank the other members of the Apes group, the anonymous reviewers of this and an earlier paper and Andrew Tuson for invaluable comments and discussions.  ... 
doi:10.1613/jair.711 fatcat:cx3mvsob55fithdfiu4tnekzae

A theory of non-equilibrium local search on random satisfaction problems [article]

Erik Aurell, Eduardo Domínguez, David Machado, R. Mulet
2019 arXiv   pre-print
We study local search algorithms to solve instances of the random k-satisfiabi lity problem, equivalent to finding (if they exist) zero-energy ground states of statistical models with disorder on random  ...  In this paper we introduce such a theory based on the recently developed technique of cavity master equations and test it on the paradigmatic random 3-satisfiability problem.  ...  (Bottom) FMS's dependency on N for η = 0.45 and α = 3.6 < αc. FIG. 2 . 2 CME results on 3-SAT instances.  ... 
arXiv:1903.01510v1 fatcat:5lyoicm5hzbsvidt6hojl6yiwy

Configuration landscape analysis and backbone guided local search

Weixiong Zhang
2004 Artificial Intelligence  
Our experimental results show that backbone-guided local search is effective on overconstrained random Max-SAT instances.  ...  Moreover, on large problem instances from a SAT library (SATLIB), the backbone guided WalkSAT algorithm finds satisfiable solutions more often than WalkSAT on SAT problem instances, and obtains better  ...  Thanks to Henry Kautz for making the  ... 
doi:10.1016/j.artint.2004.04.001 fatcat:d4asotzy3vdjlm7rh6clpffiny

Community-Based Partitioning for MaxSAT Solving [chapter]

Ruben Martins, Vasco Manquinho, Inês Lynce
2013 Lecture Notes in Computer Science  
These algorithms rely on successive calls to a SAT solver, where an unsatisfiable subformula is identified at each iteration.  ...  Unsatisfiability-based algorithms for Maximum Satisfiability (Max-SAT) have been shown to be very effective in solving several classes of problem instances.  ...  Furthermore, the partitioning approaches proposed in this paper are not limited to the WBO algorithm and will be used in other unsatisfiability-based algorithms.  ... 
doi:10.1007/978-3-642-39071-5_14 fatcat:bn2hpkewtvgljlrolynqsuesdy

A novel local search based on variable-focusing for random K-SAT [article]

Rémi Lemoy, Mikko Alava, Erik Aurell
2013 arXiv   pre-print
The new method works by picking uniformly random variables in unsatisfied clauses. A Variable-based Focused Metropolis Search (V-FMS) is then applied to random 3-SAT.  ...  We introduce a new local search algorithm for satisfiability problems. Usual approaches focus uniformly on unsatisfied clauses.  ...  Introduction Focused local search algorithms have been found to be fairly efficient in solving random instances of the Boolean satisfiability problem (K-SAT), a famous NP-complete problem for K ≥ 3 [1  ... 
arXiv:1311.2914v2 fatcat:rbeloalkinaapilij3iuonkxj4

Local Search for Unsatisfiability [chapter]

Steven Prestwich, Inês Lynce
2006 Lecture Notes in Computer Science  
Local search is widely applied to satisfiable SAT problems, and on some classes outperforms backtrack search.  ...  An intriguing challenge posed by Selman, Kautz and McAllester in 1997 is to use it instead to prove unsatisfiability. We investigate two distinct approaches.  ...  Acknowledgements Thanks to Eli Ben-Sasson for advice on resolution, and to the anonymous referees for many helpful comments.  ... 
doi:10.1007/11814948_28 fatcat:hkpkfyqcwfezfnpcsepsactwnq

Solving Stochastic Boolean Satisfiability under Random-Exist Quantification

Nian-Ze Lee, Yen-Shi Wang, Jie-Hong R. Jiang
2017 Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence  
Experimental results show that our method outperforms the state-of-the-art algorithm on random k-CNF formulas and has effective application to approximate SSAT on circuit benchmarks.  ...  This paper focuses on random-exist quantified SSAT formulas, and proposes an algorithm combining binary decision diagram (BDD), logic synthesis, and modern SAT techniques to improve computational efficiency  ...  Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence  ... 
doi:10.24963/ijcai.2017/96 dblp:conf/ijcai/LeeWJ17 fatcat:lcgtk2zz75gqvcz2jwzzikvq3q
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