Mathematical Methods of Operations Research

, Volume 64, Issue 1, pp 17–31 | Cite as

On the Existence of Solutions of Quasi-equilibrium Problems with Constraints

  • N. B. Minh
  • N. X. TanEmail author
Original Article


The quasi-equilibrium problems with constraints are formulated and some sufficient conditions on the existence of their solutions are shown. As special cases, we obtain several results on the existence of solutions of some vector quasivariational inequality and vector optimization problems. An application of the obtained results is given to show the existence of solutions of quasi-optimization problems with constraints.


Upper quasi-equilibrium problem Lower quasi-equilibrium problem α Quasi-optimization problems Vector optimization problem Quasi-equilibrium problems Diagonally quasiconvex functions Diagonally upper and lower (T,C)-quasiconvex multivalued mappings Upper and lower C- continuous multivalued mappings 

AMS Subject Classification

90C 90D 49J 


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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Hanoi University of CommerceHanoiVietnam
  2. 2.Institute of MathematicsHanoiVietnam

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