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31.
Multi-objective optimization using evolutionary algorithms identifies Pareto-optimal alternatives or their close approximation by means of a sequence of successive local improvement moves. While several successful applications to combinatorial optimization problems are known, studies of underlying problem structures are still scarce. 相似文献
32.
Philip Sternberg 《Journal of Combinatorial Theory, Series A》2007,114(5):809-824
Let g be a Lie algebra all of whose regular subalgebras of rank 2 are type A1×A1, A2, or C2, and let B be a crystal graph corresponding to a representation of g. We explicitly describe the local structure of B, confirming a conjecture of Stembridge. 相似文献
33.
We deal with the differential conditions for local optimality. The conditions that we derive for inequality constrained problems
do not require constraint qualifications and are the broadest conditions based on only first-order and second-order derivatives.
A similar result is proved for equality constrained problems, although the necessary conditions require the regularity of
the equality constraints. 相似文献
34.
Yan-hua WANG & Xiao-wu CHEN Department of Applied Mathematics Shanghai University of Finance Economics Shanghai China Department of Mathematics University of Science Technology of China Hefei China 《中国科学A辑(英文版)》2007,50(3):450-456
Using the quiver technique we construct a class of non-graded bi-Frobenius algebras. We also classify a class of graded bi-Frobenius algebras via certain equations of structure coefficients. 相似文献
35.
Approximation of signals from local averages 总被引:4,自引:0,他引:4
This work is concerned with approximation of a signal from local averages. It improves a result of Butzer and Lei [P.L. Butzer, J. Lei, Approximation of signals using measured sampled values and error analysis, Commun. Appl. Anal. 4 (2000) 245–255]. 相似文献
36.
Alistair Savage 《Algebras and Representation Theory》2006,9(2):161-199
For irreducible integrable highest weight modules of the finite and affine Lie algebras of type A and D, we define an isomorphism between the geometric realization of the crystal graphs in terms of irreducible components of Nakajima
quiver varieties and the combinatorial realizations in terms of Young tableaux and Young walls. For type An(1), we extend the Young wall construction to arbitrary level, describing a combinatorial realization of the crystals in terms
of new objects which we call Young pyramids.
Presented by P. Littleman
Mathematics Subject Classifications (2000) Primary 16G10, 17B37.
Alistair Savage: This research was supported in part by the Natural Sciences and Engineering Research Council (NSERC) of Canada
and was partially conducted by the author for the Clay Mathematics Institute. 相似文献
37.
In this paper a cubic lattice L(S) is endowed with a symmetric implication structure and it is proved that L(S) \ {0} is a power of the three-element simple symmetric implication algebra. The Metropolis–Rota’s symmetries are obtained as partial terms in the language of symmetric implication algebras. 相似文献
38.
Robin Harte Carlos Herná ndez 《Proceedings of the American Mathematical Society》2006,134(5):1397-1404
A simple formula for the adjugate of a block triangle offers an alternative route to the determinant theory for Banach algebras.
39.
Lars Eirik Danielsen 《Journal of Combinatorial Theory, Series A》2006,113(7):1351-1367
We consider additive codes over GF(4) that are self-dual with respect to the Hermitian trace inner product. Such codes have a well-known interpretation as quantum codes and correspond to isotropic systems. It has also been shown that these codes can be represented as graphs, and that two codes are equivalent if and only if the corresponding graphs are equivalent with respect to local complementation and graph isomorphism. We use these facts to classify all codes of length up to 12, where previously only all codes of length up to 9 were known. We also classify all extremal Type II codes of length 14. Finally, we find that the smallest Type I and Type II codes with trivial automorphism group have length 9 and 12, respectively. 相似文献
40.
R. XuF.A. Davidson M.A.J. Chaplain 《Journal of Mathematical Analysis and Applications》2002,269(1):256-277
A two-species ratio-dependent predator-prey model with distributed time delay is investigated. It is shown that the system is persistent under some appropriate conditions, and sufficient conditions are obtained for both the local and global stability of the positive equilibrium of the system. 相似文献