Siegfried Schaible

Chung Yuan Christian University, Taichung, Taiwan, Taiwan

Are you Siegfried Schaible?

Claim your profile

Publications (9)5.29 Total impact

  • Article: Hybrid extragradient-like methods for generalized mixed equilibrium problems, systems of generalized equilibrium problems and optimization problems
    Lu-Chuan Ceng, Qamrul Hasan Ansari, Siegfried Schaible
    [show abstract] [hide abstract]
    ABSTRACT: In this paper, we introduce and analyze a new hybrid extragradient-like iterative algorithm for finding a common solution of a generalized mixed equilibrium problem, a system of generalized equilibrium problems and a fixed point problem of infinitely many non expansive mappings. Under some mild conditions, we prove the strong convergence of the sequence generated by the proposed algorithm to a common solution of these three problems. Such solution also solves an optimization problem. Several special cases are also discussed. The results presented in this paper are the supplement, extension, improvement and generalization of the previously known results in this area. KeywordsGeneralized mixed equilibrium problem–System of generalized equilibrium problems–Optimization problems–Hybrid extragradient-like iterative scheme–Fixed points–Nonexpansive mappings–Strong convergence
    Journal of Global Optimization 05/2012; 53(1):69-96. · 1.20 Impact Factor
  • Source
    Article: Pseudomonotone maps and the cutting plane property
    Nicolas Hadjisavvas, Siegfried Schaible
    [show abstract] [hide abstract]
    ABSTRACT: Pseudomonotone*{_{\ast}} maps are a generalization of paramonotone maps which is very closely related to the cutting plane property in variational inequality problems (VIP). In this paper, we first generalize the so-called minimum principle sufficiency and the maximum principle sufficiency for VIP with multivalued maps. Then we show that pseudomonotonicity*{_{\ast}} of the map implies the “maximum principle sufficiency” and, in fact, is equivalent to it in a sense. We then present two applications of pseudomonotone*{_{\ast}} maps. First we show that pseudomonotone*{_{\ast}} maps can be used instead of the much more restricted class of pseudomonotone+ maps in a cutting plane method. Finally, an application to a proximal point method is given.
    Journal of Global Optimization 03/2009; 43(4):565-575. · 1.20 Impact Factor
  • Article: Pseudomonotone
    Nicolas Hadjisavvas, Siegfried Schaible
    J. Global Optimization. 01/2009; 43:565-575.
  • Article: Existence of solutions of vector variational inequalities and vector complementarity problems.
    Qamrul Hasan Ansari, Ali P. Farajzadeh, Siegfried Schaible
    J. Global Optimization. 01/2009; 45:297-307.
  • Chapter: Generalized Monotone Maps
    [show abstract] [hide abstract]
    ABSTRACT: We first present nine kinds of (generalized) monotone maps and in case of gradient maps their counterpart of nine kinds of (generalized) convex functions. In addition we present topologically pseudomonotone maps. We then derive sufficient and/or necessary conditions for various kinds of generalized monotonicity for several subclasses of maps. We study differentiable maps, locally Lipschitz maps, general continuous maps and affine maps.
    12/2004: pages 387-420;
  • Source
    Article: The system of generalized vector equilibrium problems with applications
    Qamrul Hasan Ansari, Siegfried Schaible, Jen-Chih Yao
    [show abstract] [hide abstract]
    ABSTRACT: In this paper, we introduce the system of generalized vector equilibrium problems which includes as special cases the system of generalized implicit vector variational inequality problems, the system of generalized vector variational and variational-like inequality problems and the system of vector equilibrium problems. By using a maximal element theorem, we establish existence results for a solution of these systems. As an application, we derive existence results for a solution of a more general Nash equilibrium problem for vector-valued functions.
    Journal of Global Optimization 12/2001; 22(1):3-16. · 1.20 Impact Factor
  • Article: η-Pseudolinearity
    Qamrul Hasan Ansari, Siegfried Schaible, Jen-Chih Yao
    [show abstract] [hide abstract]
    ABSTRACT: The notion of η-pseudolinearity is introduced. First, some characterizations of an η-pseudolinear function are obtained. Then characterizations of the solution set of an η-pseudolinear program are derived. The paper generalizes various results on pseudolinear functions and programs. Il lavoro introduce la nozione di η-pseudolinearità. Dopo avere ottenuto alcune caratterizzazioni delle funzioni η-pseudolineari, si derivano caratterizzazioni dell'insieme delle soluzioni di un programma η-pseudolineare. Lo studio generalizza diversi risultati sulle funzioni e sui programmi pseudolineari.
    Rivista di Matematica per le Scienze Economiche e Sociali 04/1999; 22(1):31-39.
  • Article: On the equivalence of nonlinear complementarity problems and least-element problems
    Siegfried Schaible, Jen-Chih Yao
    [show abstract] [hide abstract]
    ABSTRACT: Strictly pseudomonotoneZ-maps operating on Banach lattices are considered. Equivalence of complementarity problems and least-element problems is established under certain regularity and growth conditions. This extends a recent result by Riddell (1981) for strictly monotoneZ-maps to the pseudomonotone case. Some other problems equivalent to the above are discussed as well.
    Mathematical Programming 09/1995; 70(1):191-200. · 1.71 Impact Factor
  • Source
    Article: Recent developments in solution methods for variational inequalities and fixed point problems
    Siegfried Schaible, Jen-Chih Yao
    [show abstract] [hide abstract]
    ABSTRACT: In this paper, we report recent developments in solution methods for finding a common element of the fixed point set of a mapping and the solution set of the variational inequality in a Hilbert space. Key–Words: Variational inequality; Asymptotically strict pseudocontractive mapping in the intermediate sense; Fixed point; α-inverse strongly monotone mapping.

Institutions

  • 2012
    • Chung Yuan Christian University
      Taichung, Taiwan, Taiwan
    • Shanghai Normal University
      Shanghai, Shanghai Shi, China
  • 1995–2004
    • University of California, Riverside
      Riverside, CA, USA
  • 2001
    • Aligarh Muslim University
      • Department of Mathematics
      Alīgarh, Uttar Pradesh, India