Journal of Global Optimization

, Volume 49, Issue 3, pp 381–396 | Cite as

On generalized Ekeland’s variational principle and equivalent formulations for set-valued mappings

  • P. Q. Khanh
  • D. N. Quy


We propose a very weak type of generalized distances called a weak τ-function and use it to weaken the assumptions about lower semicontinuity in existing versions of Ekeland’s variational principle and equivalent formulations.


Locally convex spaces Weak τ-functions Ekeland’s variational principle K-lower semicontinity from above Lower closedness 


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© Springer Science+Business Media, LLC. 2010

Authors and Affiliations

  1. 1.Department of MathematicsInternational University of Hochiminh CityHochiminh CityVietnam
  2. 2.Department of MathematicsCantho UniversityCanthoVietnam

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