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71.
72.
A. Birštunas 《Lithuanian Mathematical Journal》2008,48(2):174-187
We study sequent calculus for multi-modal logic K D45n and its complexity. We introduce a loop-check free sequent calculus. Loop-check is eliminated by using the marked modal operator
□i•, which is used as an alternative to sequents with histories ([8], [3], [5]). All inference rules are invertible or semi-invertible.
To get this, we use or branches beside common and branches. We prove the equivalence between known sequent calculus and our newly introduced efficient sequent calculus.
We concentrate on the complexity analysis of the introduced sequent calculus for multi-modal logic K D45n. We prove that the space complexity of the given calculus is polynomial (O(l
3)). We show the maximum height of the constructed derivation tree that leads to the reduction of the time and space complexity.
We present a decision algorithm for multi-modal logic K D45n and some nontrivial examples to improve the introduced loop-check free sequent calculus. 相似文献
73.
Valeriy K. Bulitko 《Mathematical Logic Quarterly》1999,45(4):561-571
We apply complexity concepts to define a new sort of sub-Turing reducibilities ≤ ?? make the degree hierarchy thinner and to obtain some new specifications of the well known jump inversion theorem of Friedberg. We show that this theorem doesn't hold when ≤ T is replaced with ≤ ??, where ?? is any countable subset of the class ?? of all total increasing functions f : ? → ?. 相似文献
74.
75.
We establish NP-completeness of two problems on core stable coalitions in hedonic games. In the first problem every player has only two acceptable coalitions in his preference list, and in the second problem the preference structures arise from the distances in an underlying metric space. 相似文献
76.
Computing the minimal covering set 总被引:1,自引:0,他引:1
We present the first polynomial-time algorithm for computing the minimal covering set of a (weak) tournament. The algorithm draws upon a linear programming formulation of a subset of the minimal covering set known as the essential set. On the other hand, we show that no efficient algorithm exists for two variants of the minimal covering set–the minimal upward covering set and the minimal downward covering set–unless P equals NP. Finally, we observe a strong relationship between von Neumann–Morgenstern stable sets and upward covering on the one hand, and the Banks set and downward covering on the other. 相似文献
77.
The overlay of 2≤m≤d minimization diagrams of n surfaces in ℝ
d
is isomorphic to a substructure of a suitably constructed minimization diagram of mn surfaces in ℝ
d+m−1. This elementary observation leads to a new bound on the complexity of the overlay of minimization diagrams of collections
of d-variate semi-algebraic surfaces, a tight bound on the complexity of the overlay of minimization diagrams of collections of
hyperplanes, and faster algorithms for constructing such overlays. Further algorithmic implications are discussed.
Work by V. Koltun was supported by NSF CAREER award CCF-0641402.
Work by M. Sharir was supported by NSF Grants CCR-00-98246 and CCF-05-14079, by a grant from the Israeli Academy of Sciences
for a Center of Excellence in Geometric Computing at Tel Aviv University, and by the Hermann Minkowski Minerva Center for
Geometry at Tel Aviv University. 相似文献
78.
79.
80.
Zvi Drezner 《Mathematical Programming》1987,38(2):219-222
We present an exchange algorithm for the solution of minimax optimization problems involving convex functions. For a certain
class of functions, the complexity of this algorithm is shown to be either linear in the number of functions, or at least
squared in that number. 相似文献