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831.
We consider a generalized equilibrium problem involving DC functions which is called (GEP). For this problem we establish
two new dual formulations based on Toland-Fenchel-Lagrange duality for DC programming problems. The first one allows us to
obtain a unified dual analysis for many interesting problems. So, this dual coincides with the dual problem proposed by Martinez-Legaz
and Sosa (J Glob Optim 25:311–319, 2006) for equilibrium problems in the sense of Blum and Oettli. Furthermore it is equivalent
to Mosco’s dual problem (Mosco in J Math Anal Appl 40:202–206, 1972) when applied to a variational inequality problem. The
second dual problem generalizes to our problem another dual scheme that has been recently introduced by Jacinto and Scheimberg
(Optimization 57:795–805, 2008) for convex equilibrium problems. Through these schemes, as by products, we obtain new optimality
conditions for (GEP) and also, gap functions for (GEP), which cover the ones in Antangerel et al. (J Oper Res 24:353–371,
2007, Pac J Optim 2:667–678, 2006) for variational inequalities and standard convex equilibrium problems. These results, in
turn, when applied to DC and convex optimization problems with convex constraints (considered as special cases of (GEP)) lead
to Toland-Fenchel-Lagrange duality for DC problems in Dinh et al. (Optimization 1–20, 2008, J Convex Anal 15:235–262, 2008),
Fenchel-Lagrange and Lagrange dualities for convex problems as in Antangerel et al. (Pac J Optim 2:667–678, 2006), Bot and
Wanka (Nonlinear Anal to appear), Jeyakumar et al. (Applied Mathematics research report AMR04/8, 2004). Besides, as consequences
of the main results, we obtain some new optimality conditions for DC and convex problems. 相似文献
832.
Nguyen Thieu Huy 《Journal of Functional Analysis》2006,235(1):330-354
Consider an evolution family U=(U(t,s))t?s?0 on a half-line R+ and an integral equation . We characterize the exponential dichotomy of the evolution family through solvability of this integral equation in admissible function spaces which contain wide classes of function spaces like function spaces of Lp type, the Lorentz spaces Lp,q and many other function spaces occurring in interpolation theory. We then apply our results to study the robustness of the exponential dichotomy of evolution families on a half-line under small perturbations. 相似文献
833.
We prove that a real function is operator monotone (operator convex) if the corresponding monotonicity (convexity) inequalities
are valid for some normal state on the algebra of all bounded operators in an infinite-dimensional Hilbert space. We describe
the class of convex operator functions with respect to a given von Neumann algebra in dependence of types of direct summands
in this algebra. We prove that if a function from ℝ+ into ℝ+ is monotone with respect to a von Neumann algebra, then it is also operator monotone in the sense of the natural order on
the set of positive self-adjoint operators affiliated with this algebra. 相似文献
834.
In this paper, we consider the following nonlinear Kirchhoff wave equation 相似文献
$\left\{\begin{array}{l}u_{tt}-\frac{\partial }{\partial x}(\mu (u,\Vert u_{x}\Vert ^{2})u_{x})=f(x,t,u,u_{x},u_{t}),\quad 0
where \(\widetilde{u}_{0}\), \(\widetilde{u}_{1}\), μ, f, g are given functions and \(\Vert u_{x}\Vert ^{2}=\int_{0}^{1}u_{x}^{2}(x,t)dx.\) To the problem (1), we associate a linear recursive scheme for which the existence of a local and unique weak solution is proved by applying the Faedo–Galerkin method and the weak compact method. In particular, motivated by the asymptotic expansion of a weak solution in only one, two or three small parameters in the researches before now, an asymptotic expansion of a weak solution in many small parameters appeared on both sides of (1)1 is studied.(1)
835.
Phan Quoc Khanh Dinh Ngoc Quy 《Nonlinear Analysis: Theory, Methods & Applications》2010,73(7):2245-2259
We propose a definition of lower closed transitive relations and prove the existence of minimal elements for such a relation. This result is shown to contain probably a large part of existing versions of Ekeland’s variational principle (EVP). We introduce the notion of a weak τ-function p as a generalized distance and use it together with the above result on minimal elements to establish enhanced EVP for various settings, under relaxed lower semicontinuity assumptions. These principles conclude the existence not only of p-strict minimizers of p-perturbations of the considered vector function, but also p-sharp and p-strong minimizers. Our results are proved to be stronger than the classical EVP and many generalizations in the literature, even in the usual one-dimensional case, by numerous corollaries and examples. We include equivalent formulations of our enhanced EVP as well. 相似文献
836.
A homologous series of 4 - alkoxyphenyl-4′-[4″-cyano-benzyloxy] benzoates have been synthesized. Within this series three smectic A phases : SA 1, SA d and SA 2 were identified by mean of small angle X-Ray scattering. Furthermore three derivatives exhibit the novel smectic phase made of ribbons S~C. 相似文献
837.
Mesomorphic Properties of Di- (4 - Alkoxyphenyl) and Di- (4 - Alkanoyloxyphenyl) Tetrathiafulvalenes
A. Babeau Nguyen Huu Tinh H. Gasparoux C. Polycarpe E. Torreilles L. Giral 《Molecular Crystals and Liquid Crystals》2013,570(5-6):171-176
The polymorphism of the di- (4 - alkoxyphenyl) and di- (4 - alkanoyloxyphenyl) tetrathiafulvalenes (TTF) is investigated. In the dialkoxy series, the short chain derivative exhibits a smectic G phase and a nematic phase. The latter phase disappears in the long chain derivative. The dialkanoyloxy derivatives exhibit a smectic G phase (for short chains) and a smectic C phase (for long chains). A plot of the mesormorphic-isotropic transition temperatures against the number of carbon atoms of the substituent shows the usual odd-even effect. Some tetra (alkoxyphenyl) tetrathiafulvalenes are described, unfortunately they have no mesomorphic properties. 相似文献
838.
839.
R. Farhi A. Andreau E. Andreoli De Oliveira J-P. Marcerou H. T. Nguyen J-M. Tarascon 《Molecular Crystals and Liquid Crystals》2013,570(1):875-882
Abstract The use of Raman scattering technique as a tool for studying local order in complex liquid crystal systems is illustrated by three examples, namely the locally anisotropic liquid L-phase, lipid membranes, and PDLC's. 相似文献
840.
C.-P. S. Anthony Liu D. C. Nguyen P. Neogi 《Journal of Macromolecular Science: Physics》2013,52(2-3):203-220
The chemical potential of a solute in a solid polymer includes contributions from solute-polymer chain conformations, Flory-Huggins type interaction, and elastic energy of swelling. Presence of impermeable and rigid crystallites in such systems is expected to affect all these contributions. Theoretical calculations have been performed to check the direct effects of constrained chain conformations in the amorphous domains in semicrystalline polymers. Experimental results are used to determine Flory-Huggins coefficient and elastic modulus. From all these, the primary effects are shown to be on the entropic part of the Flory-Huggins coefficient and an increase in the elastic modulus by one or two order of magnitude. Finally, these results are used to calculate the rates of solvent-induced crystallization to show that these rates can drop to negligible values as the amount of crystals formed rises. Thus, the actual degree of crystallization can lie well below the Flory-Yoon limit. 相似文献