Results 51 to 60 of about 343 (158)
Critical point result of Schechter type in a Banach space
Electronic Journal of Qualitative Theory of Differential Equations, 2016 Using Ekeland's variational principle we give a critical point theorem of Schechter type for extrema on a sublevel set in a Banach space. This result can be applied to localize the solutions of PDEs which contain nonlinear homogeneous operators.
Hannelore Lisei, Orsolya Vas
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Local completeness, drop theorem and Ekeland's variational principle
, 2005 By using a very general drop theorem in locally convex spaces we obtain some extended versions of Ekeland's variational principle, which only need assume local completeness of some related sets and improve Hamel's recent results.
Qiu, Jing-Hui
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A minimization theorem in quasi-metric spaces and its applications
International Journal of Mathematics and Mathematical Sciences, 2002 We prove a new minimization theorem in quasi-metric spaces, which improves the results of Takahashi (1993). Further, this theorem is used to generalize Caristi's fixed point theorem and Ekeland's ϵ-variational principle.
Jeong Sheok Ume
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Positive solution for a nonlocal problem with strong singular nonlinearity
Open Mathematics, 2023 In this article, we consider a nonlocal problem with a strong singular term and a general weight function. By using Ekeland’s variational principle, we prove a necessary and sufficient condition for the existence of a positive solution.
Wang Yue +3 more
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An extension of Ekeland's variational principle to locally complete spaces
, 2007 We prove an extension of Ekeland's variational principle to locally complete spaces which uses subadditive, strictly increasing continuous functions as ...
García, C.L., García, A., Bosch, C.
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Demonstratio MathematicaIn this paper, we establish a new version of Ekeland’s variational principle in the setting of Kaleva-Seikkala’s type fuzzy metric spaces, where the objective function is an interval-valued function defined on a fuzzy metric space, and the perturbation ...
Liu Xuan, He Fei, Lu Ning
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Nash-type equilibria and periodic solutions to nonvariational systems
Advances in Nonlinear Analysis, 2014 The paper deals with variational properties of fixed points for contraction-type operators. Under suitable conditions, the unique fixed point of a vector-valued operator is a Nash-type equilibrium of the corresponding energy functionals. This is achieved
Precup Radu
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Boundary Value Problems, 2019 In this paper, we investigate the quasilinear elliptic equations involving multiple critical Sobolev–Hardy terms with Dirichlet boundary conditions on bounded smooth domains Ω⊂RN $\varOmega \subset R^{N}$ ( N≥3 ${N \ge 3} $), and prove the multiplicity ...
Yuanyuan Li
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Product differentiation in the fruit industry: Lessons from trademarked apples
Agribusiness, Volume 42, Issue 1, Page 148-174, Winter 2026.Abstract We derive price premiums for patented or trademarked apple varieties, also known as “club apples,” compared to open‐variety apples. We use an expansive retail scanner dataset, along with unique data on apple taste characteristics, to estimate monthly club apple premiums for 2008–2018.
Modhurima Dey Amin +3 more
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The density of extremal points in Ekeland's variational principle
, 2007 In this paper, we investigate the density of extremal points appeared in Ekeland's variational principle. By introducing radial intersections of sets, we give a very general result on the density of extremal points in the framework of locally convex ...
Qiu, Jing-Hui
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