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1.
We present a new generic problem solving approach for over-constrained problems based on Max-SAT. We first define a Boolean
clausal form formalism, called soft CNF formulas, that deals with blocks of clauses instead of individual clauses, and that allows one to declare each block either as hard (i.e., must be satisfied by any solution) or soft (i.e., can be violated by some solution). We then present two Max-SAT solvers that find a truth assignment that satisfies
all the hard blocks of clauses and the maximum number of soft blocks of clauses. Our solvers are branch and bound algorithms
equipped with original lazy data structures, powerful inference techniques, good quality lower bounds, and original variable
selection heuristics. Finally, we report an experimental investigation on a representative sample of instances (random 2-SAT,
Max-CSP, graph coloring, pigeon hole and quasigroup completion) which provides experimental evidence that our approach is
very competitive compared with the state-of-the-art approaches developed in the CSP and SAT communities.
Research partially supported by projects TIN2004-07933-C03-03 and TIC2003-00950 funded by the Ministerio de Educación y Ciencia. The second author is supported by a grant Ramón y Cajal. 相似文献
2.
Sylvia Pulmannová 《International Journal of Theoretical Physics》2004,43(7-8):1573-1585
Divisible effect algebras and their relations to convex effect algebras and MV-algebras are studied. A categorical equivalence between divisible effect algebras and rational vector spaces is proved. Infinitesimal, sharp and extremal elements in divisible effect algebras are studied and their relations to properties of the state space are shown. 相似文献
3.
Sylvia Pulmannová 《International Journal of Theoretical Physics》2003,42(5):907-919
Tensor products of quantum logics and effect algebras with some known problems are reviewed. It is noticed that although tensor products of effect algebras having at least one state exist, in the category of complex Hilbert space effect algebras similar problems as with tensor products of projection lattices occur. Nevertheless, if one of the two coupled physical systems is classical, tensor product exists and can be considered as a Boolean power. Some applications of tensor products (in the form of Boolean powers) to quantum measurements are reviewed. 相似文献
4.
5.
Robert Andreu Gerard Lligadas Joan Carles Ronda Marina Galià Virginia Cádiz 《Journal of polymer science. Part A, Polymer chemistry》2007,45(21):4965-4973
A new oxazolidine derivative was obtained from phenol, 2‐amino‐2‐methylpropane‐1,3‐diol and paraformaldehyde. The reaction of this novel oxazolidine diol with phenylisocyanate lead to a urethane model compound which can be polymerized thermally by oxazolidine ring opening to give a Mannich bridge structure. Linear segmented polyurethanes were prepared by reaction of different ratios of oxazolidine diol and commercial polyethylenglycol (Mw ~ 400) with 4,4′‐methylenbis (cyclohexylisocyanate) (HMDI, 90% isomers mixture). The polyurethanes were thermally characterized and crosslinked by oxazolidine ring opening to obtain materials which showed improved thermal stability. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4965–4973, 2007 相似文献
6.
Application of graph-theoretic methods to new perimeter polynomials for connected clusters on a lattice yields extra data on the total number of clusters and for the coefficients in the series expansion for the mean size of clusters at low densities. The lattices studied are the square, the square with next nearest neighbors, the triangular, and the simple cubic. 相似文献
7.
8.
General and selective isolation procedure for high-performance liquid chromatographic determination of anabolic steroids in tissues 总被引:5,自引:0,他引:5
A multi-residue method has been developed for the determination of anabolic steroids in animal tissue. The analytes are extracted from tissue with methanol and the extract is subjected to two solid-phase extractions, one using a non-specific adsorbing material, such as graphitized carbon black (Carbopack B), and the other Amberlite CG-400 I in the OH form. This procedure allowed the neutral anabolics (testosterone, trenbolone and progesterone) to be isolated and separated from the acidic type (phenolic group), such as diethylstilbestrol, oestradiol, zeranol/zearalenone and their respective metabolites. The determination was effected using high-performance liquid chromatography with different detectors (ultraviolet, fluorimetric and electrochemical). Several analytical parameters were studied: chromatographic conditions, recoveries, evaporation step, solvent flow-rate, cartridges reusability, interference of plastic cartridges. For all the anabolics investigated the recoveries were greater than 83.6%. 相似文献
9.
A. Badalà R. Barbera G. Lo Re A. Palmeri G. S. Pappalardo A. Pulvirenti F. Riggi 《Acta Physica Hungarica A》2006,25(2-4):337-346
Results are shown from a Monte Carlo simulation study of the capabilities of the Inner Tracking System of the ALICE experiment, used in standalone mode, for HBT analysis of Pb?Pb collisions at LHC energies (5.5 ATeV). Different values of the coherence factor and the Gaussian source radius have been studied. For this purpose, a specific ITS stand-alone tracking algorithm, based on the Denby-Peterson neural algorithm, has been developed. 相似文献
10.
For any unit vector in an inner product space S, we define a mapping on the system of all -closed subspaces of S, F(S), whose restriction on the system of all splitting subspaces of S, E(S), is always a finitely additive state. We show that S is complete iff at least one such mapping is a finitely additive state on F(S). Moreover, we give a completeness criterion via the existence of a regular finitely additive state on appropriate systems of subspaces. Finally, the result will be generalized to general inner product spaces. 相似文献