Results 31 to 40 of about 1,156,553 (130)

Caffarelli–Kohn–Nirenberg inequality for biharmonic equations with inhomogeneous term and Rellich potential

open access: yesElectronic Journal of Qualitative Theory of Differential Equations, 2023
In this article, multiplicity of nontrivial solutions for an inhomogeneous singular biharmonic equation with Rellich potential are studied. Firstly, a negative energy solution of the studied equations is achieved via the Ekeland's variational principle ...
Yang Yu, Yulin Zhao
doaj   +1 more source

Maximum principle for near-optimality of stochastic delay control problem

open access: yesAdvances in Difference Equations, 2017
This paper is concerned with near-optimality for stochastic control problems of linear delay systems with convex control domain and controlled diffusion. Necessary and sufficient conditions for a control to be near-optimal are established by Pontryagin’s
Feng Zhang
doaj   +1 more source

Critical point result of Schechter type in a Banach space

open access: yesElectronic 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
doaj   +1 more source

Ekeland’s variational principle with weighted set order relations

open access: yes, 2020
The main results of the paper are a minimal element theorem and an Ekeland-type variational principle for set-valued maps whose values are compared by means of a weighted set order relation. This relation is a mixture of a lower and an upper set relation
Ansari, Qamrul Hasan   +2 more
core   +1 more source

Existence for Elliptic Equation Involving Decaying Cylindrical Potentials with Subcritical and Critical Exponent

open access: yesInternational Journal of Differential Equations, 2015
We consider the existence of nontrivial solutions to elliptic equations with decaying cylindrical potentials and subcritical exponent. We will obtain a local minimizer by using Ekeland’s variational principle.
Mohammed El Mokhtar Ould El Mokhtar
doaj   +1 more source

A minimization theorem in quasi-metric spaces and its applications

open access: yesInternational 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
doaj   +1 more source

Positive solution for a nonlocal problem with strong singular nonlinearity

open access: yesOpen 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
doaj   +1 more source

Ekeland’s variational principle for interval-valued functions with an α-level set in Kaleva-Seikkala’s type fuzzy metric spaces

open access: yesDemonstratio Mathematica
In 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
doaj   +1 more source

Product differentiation in the fruit industry: Lessons from trademarked apples

open access: yesAgribusiness, 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
wiley   +1 more source

Nash-type equilibria and periodic solutions to nonvariational systems

open access: yesAdvances 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
doaj   +1 more source

Home - About - Disclaimer - Privacy