Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 60 (1993), S. 93-113 
    ISSN: 1436-4646
    Keywords: 26B25 ; 90C20 ; Quadratic functions ; quasiconvexity ; subdifferentiability ; cutting plane methods
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract In this paper we characterize those quadratic functions whose restrictions to a convex set are boundedly lower subdifferentiable and, for the case of closed hyperbolic convex sets, those which are lower subdifferentiable but not boundedly lower subdifferentiable. Once characterized, we will study the applicability of the cutting plane algorithm of Plastria to problems where the objective function is quadratic and boundedly lower subdifferentiable.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 65 (1994), S. 1-20 
    ISSN: 1436-4646
    Keywords: Efficient decomposition ; Moreau decomposition ; partially ordered vector spaces
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract LetK 1 andK 2 be two convex cones in some common vector space. This paper is concerned with the question of finding a ‘good’ decomposition, with respect toK 1 andK 2, of a given element of the Minkowski sumK 1 +K 2. We propose the criterion of efficiency as a measure for the quality of a decomposition. This criterion allows us to set up a framework from which a general cone decomposition theory is then derived.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical methods of operations research 27 (1983), S. 257-266 
    ISSN: 1432-5217
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Description / Table of Contents: Zusammenfassung In der vorliegenden Arbeit wird die Konjugierte einer quasikonvexen Funktion eingeführt, ohne dabei Halbstetigkeit oder Normalität vorauszusetzen, um übereinstimmung der zweiten Konjugierten mit der quasikonvexen Hüllenfunktion zu garantieren. Dies wird durch eine Verallgemeinerung der sogenanntenH-Konjugation erreicht und basiert auf einem Trennungssatz für allgemeine Halbräume. Die Theorie wird dazu herangezogen, ein duales Programm einzuführen, welches ein quasikonkaves Maximumproblem ist, das eine Matrix als Variable hat und stets eine optimale Lösung besitzt. Die Abwesenheit einer Dualitätslücke ist damit gleichbedeutend, daß die Störfunktion im Ursprung quasikonvex ist. Es wird eine Lagrangefunktion für allgemeine Probleme eingeführt und mit derjenigen Luenbergers im Falle vertikaler Störungen verglichen.
    Notes: Abstract In this article we develop a conjugacy theory in quasiconvex analysis, in which no lower semicontinuity or normality assumption is needed to ensure the coincidence of the second conjugate of any function with its quasivonvex hull. This is made by an extension of the concept ofH-conjugation, and is based on a separation theorem by general halfspaces. The theory is applied in mathematical programming to define dual problems, which consist in maximizing a quasiconcave function of matricial variable, the optimum being always attained. The absence of duality gap is equivalent to the quasiconvexity of the perturbation function at the origin. A Lagrangian for general problems is studied and compared with the one of Luenberger in the case of vertical perturbations.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical methods of operations research 35 (1991), S. 221-230 
    ISSN: 1432-5217
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics , Economics
    Notes: Summary We give several characterizations of efficient solutions of subsets ofR p (with respect to compatible preorders) in terms of the lexicographical order, under the assumptions that the set of admissible points is a convex polyhedron or the nonnegative cone corresponding to the preorder is polyhedral. We also characterize the lexicographical minimum of a convex polyhedron by means of the componentwise order and unitary lower triangular matrices.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of optimization theory and applications 82 (1994), S. 159-167 
    ISSN: 1573-2878
    Keywords: Alternative theorems ; quadratic forms
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract LetA 1 andA 2 be two symmetric matrices of ordern×n. According to Yuan, there exists a convex combination of these matrices which is positive semidefinite, if and only if the functionx∈R n ↦ max {x T A 1 x,x T A 2 x} is nonnegative. We study the case in which more than two matrices are involved. We study also a related question concerning the maximization of the minimum eigenvalue of a convex combination of symmetric matrices.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of optimization theory and applications 68 (1991), S. 95-116 
    ISSN: 1573-2878
    Keywords: Fractional programming ; lower subdifferentiable functions ; duality ; optimality conditions ; cutting planes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract The notion of lower subdifferentiability is applied to the analysis of convex fractional programming problems. In particular, duality results and optimality conditions are presented, and the applicability of a cutting-plane algorithm using lower subgradients is discussed. These methods are useful also in generalized fractional programming, where, in the linear case, the performance of the cutting-plane algorithm is compared with that of the most efficient version of the Dinkelbach method, which is based on the solution of a parametric linear programming problem.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of optimization theory and applications 88 (1996), S. 365-379 
    ISSN: 1573-2878
    Keywords: Continuous convex sets ; support functions ; convex duality ; coercivity ; recession cones
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Convex functions with continuous epigraph in the sense of Gale and Klée have been studied recently by Auslender and Coutat in a finite-dimensional setting. Here, we provide characterizations of such functionals in terms of the Legendre-Fenchel transformation in general locally convex spaces. Also, we show that the concept of continuous convex sets is of interest in these spaces. We end with a characterization of convex functions on Euclidean spaces with continuous level sets.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Journal of optimization theory and applications 95 (1997), S. 717-722 
    ISSN: 1573-2878
    Keywords: Quasiconvex functions ; duality ; generalized conjugation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract A function defined on a locally convex space is called evenly quasiconvex if its level sets are intersections of families of open half-spaces. Furthermore, if the closures of these open halfspaces do not contain the origin, then the function is called R-evenly quasiconvex. In this note, R-evenly quasiconvex functions are characterized as those evenly-quasiconvex functions that satisfy a certain simple relation with their lower semicontinuous hulls.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...