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941.
There have been recent advances in the construction of algebraic curves for certain classes of string solutions in the context of the AdS/CFT correspondence. In this paper we obtain the Lax operators and associated spectral curves for circular and folded string solutions in AdS . In addition, we provide an original approach for the reconstruction of string solutions in S3 from their corresponding curves. 相似文献
942.
943.
In this paper, under the assumption that the perturbation function satisfies a growth condition, necessary and sufficient conditions for an exact penalty representation and a zero duality gap property between the primal problem and its augmented Lagrangian dual problem are established. 相似文献
944.
The problems of (bi-)proportional rounding of a nonnegative vector or matrix, resp., are written as particular separable convex
integer minimization problems. Allowing any convex (separable) objective function we use the notions of vector and matrix
apportionment problems. As a broader class of problems we consider separable convex integer minimization under linear equality
restrictions Ax = b with any totally unimodular coefficient matrix A. By the total unimodularity Fenchel duality applies, despite the integer restrictions of the variables. The biproportional
algorithm of Balinski and Demange (Math Program 45:193–210, 1989) is generalized and derives from the dual optimization problem.
Also, a primal augmentation algorithm is stated. Finally, for the smaller class of matrix apportionment problems we discuss
the alternating scaling algorithm, which is a discrete variant of the well-known Iterative Proportional Fitting procedure. 相似文献
945.
Hong-Kun Xu 《Journal of Mathematical Analysis and Applications》2006,314(2):631-643
Let X be a Banach space and A an m-accretive operator with a zero. Consider the iterative method that generates the sequence {xn} by the algorithm xn+1=αnu+(1−αn)Jrnxn, where {αn} and {rn} are two sequences satisfying certain conditions, and Jr denotes the resolvent −1(I+rA) for r>0. Strong convergence of the algorithm {xn} is proved assuming X either has a weakly continuous duality map or is uniformly smooth. 相似文献
946.
Dual actions with respect to U(1) gauge fields for the Born-Infeld and Dp-brane theories are reexamined. Taking into account an additional condition, i.e. a corollary to the field equation of the auxiliary metric, one obtains an alternative dual action that does not involve the infinite series in the auxiliary metric given by [M. Abou Zeid and C.M. Hull, Phys. Lett. B 428 (1998) 277], but just picks out the first term from the series formally. New effective interactions of the theories are revealed. That is, the new dual action gives rise to an effective interaction in terms of one interaction term rather than infinitely many terms of different (higher) orders of interactions physically. HOwever, the price paid for eliminating the infinite series is that the new action is not quadratic but highly nonlinear in the Hodge dual of a (p - 1)-form field strength. This non-linearity is inevitable under the requirement that the two dual actions are equivalent. 相似文献
947.
主要目的是利用Liouville反转公式来给出整数素因数间的一个新的对偶公式,从而推广了K.Alladi的基于Mbius反转公式的对偶引理. 相似文献
948.
Radu Ioan Bo? Ioan Bogdan Hodrea 《Journal of Mathematical Analysis and Applications》2006,322(1):316-328
We present some Farkas-type results for inequality systems involving finitely many functions. Therefore we use a conjugate duality approach applied to an optimization problem with a composed convex objective function and convex inequality constraints. Some recently obtained results are rediscovered as special cases of our main result. 相似文献
949.
Radu Ioan Boţ Sorin-Mihai Grad Gert Wanka 《Mathematical Methods of Operations Research》2007,65(3):417-444
A general duality framework in convex multiobjective optimization is established using the scalarization with K-strongly increasing functions and the conjugate duality for composed convex cone-constrained optimization problems. Other
scalarizations used in the literature arise as particular cases and the general duality is specialized for some of them, namely
linear scalarization, maximum (-linear) scalarization, set scalarization, (semi)norm scalarization and quadratic scalarization.
相似文献
950.
Hsien-Chung Wu 《Fuzzy Optimization and Decision Making》2007,6(3):179-198
The weak and strong duality theorems in fuzzy optimization problem based on the formulation of Wolfe’s primal and dual pair
problems are derived in this paper. The solution concepts of primal and dual problems are inspired by the nondominated solution
concept employed in multiobjective programming problems, since the ordering among the fuzzy numbers introduced in this paper
is a partial ordering. In order to consider the differentiation of a fuzzy-valued function, we invoke the Hausdorff metric
to define the distance between two fuzzy numbers and the Hukuhara difference to define the difference of two fuzzy numbers.
Under these settings, the Wolfe’s dual problem can be formulated by considering the gradients of differentiable fuzzy- valued
functions. The concept of having no duality gap in weak and strong sense are also introduced, and the strong duality theorems
in weak and strong sense are then derived naturally. 相似文献