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961.
Bang-Yen Chen 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(11):3561-3571
In this paper we initiate the study of Lagrangian submanifolds in para-Kähler manifolds. In particular, we prove two general optimal inequalities for Lagrangian submanifolds of the flat para-Kähler manifold . Moreover, we completely classify Lagrangian submanifolds which satisfy the equality case of one of the two inequalities. 相似文献
962.
Existence of nonnegative solutions for a class of semilinear elliptic systems with indefinite weight
J. Tyagi 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(9):2882-2889
We prove the existence of nonnegative solutions to the system
963.
964.
João Gouveia Roland Grappe Volker Kaibel Kanstantsin Pashkovich Richard Z. Robinson Rekha R. Thomas 《Linear algebra and its applications》2013
In this paper we characterize the slack matrices of cones and polytopes among all nonnegative matrices. This leads to an algorithm for deciding whether a given matrix is a slack matrix. The underlying decision problem is equivalent to the polyhedral verification problem whose complexity is unknown. 相似文献
965.
Hong-Kun Xu 《Numerical Functional Analysis & Optimization》2013,34(1-2):157-163
Sequences (or curves) are constructed to approximate common fixed points of a pair of nonex-pansive mappings (or contraction semigroups) in Hilbert spaces. The obtained results extend the previously known results from a single mapping to a family of mappings. 相似文献
966.
967.
Given a metric continuum X, we consider the following hyperspaces of X : 2X, Cn(X) and Fn(X) (n∈N). Let F1(X)={{x}:x∈X}. A hyperspace K(X) of X is said to be rigid provided that for every homeomorphism h:K(X)→K(X) we have that h(F1(X))=F1(X). In this paper we study under which conditions a continuum X has a rigid hyperspace Fn(X). 相似文献
968.
We prove that the inverse of a mirror map for a toric Calabi–Yau manifold of the form KY, where Y is a compact toric Fano manifold, can be expressed in terms of generating functions of genus 0 open Gromov–Witten invariants defined by Fukaya–Oh–Ohta–Ono (2010) [15]. Such a relation between mirror maps and disk counting invariants was first conjectured by Gross and Siebert (2011) [24, Conjecture 0.2 and Remark 5.1] as part of their program, and was later formulated in terms of Fukaya–Oh–Ohta–Ono’s invariants in the toric Calabi–Yau case in Chan et al. (2012) [8, Conjecture 1.1]. 相似文献
969.
The Severi variety parameterizes plane curves of degree d with δ nodes. Its degree is called the Severi degree. For large enough d, the Severi degrees coincide with the Gromov–Witten invariants of CP2. Fomin and Mikhalkin (2010) [10] proved the 1995 conjecture that for fixed δ, Severi degrees are eventually polynomial in d. 相似文献
970.
N. D. Ursuljak A. V. Azizov A. M. Balbashov A. V. Belickiy G. A. Yakovlev 《Phase Transitions》2013,86(1-2):91-97
We present ab initio calculations for Si ad-atom kinetics on surfactant (As, Sb) covered Si(111) considering the structures experimentally found during homoepitaxy. On As-covered Si(111), one exclusively finds islands with double-step height which always show the equilibrium (1 2 1)-structure. On the other hand, on Sb-covered Si(111) large Si islands with single-step height appear with (1 2 1)-structure, on which smaller islands nucleate which show the ( $ \sqrt{3} \times \sqrt{3} $ )-structure of the Sb-covered terraces. The competition between diffusion of ad-atoms on top of the surfactant layer and incorporation into the layer by exchange with a surfactant atom, and the consequences for the island development on the different structures are discussed. 相似文献