We introduce the notion of a zero-scale asymptotic function. In contrast to the usual asymptotic function, which is related to the slopes of a function at infinity along a given direction, the new function is related to the jumps of the function along that direction. Applications are given to the unconstrained and the constrained optimization of quasiconvex functions. Also, the problem of quasiconvex maximization is discussed. Further, a class of quasiconvex problems is introduced, that is shown to have zero duality gap. Finally, new results on quasiconvex quadratic programming are obtained.

Contact details are reproduced from the original publication and may be historical.

Fabián Flores-Bazán

Dep. de Ingeniería Matemática, Facultad de Ciencias Físicas y Matemáticas, Universidad de Concepción, Chile

fflores@ing-mat.udec.cl

Nicolas Hadjisavvas

Dept. of Product and Systems Design Engineering, University of the Aegean, Hermoupolis, Syros, Greece
and: Mathematics and Statistics Department, King Fahd University of Petroleum and Minerals, Dhahran, Kingdom of Saudi Arabia

nhad@aegean.gr
  1. A. Auslender, M. Teboulle: Asymptotic Cones and Functions in Optimization and Variational Inequalities, Springer, Berlin (2003).Google Scholar
  2. C. Baiocchi, G. Buttazzo, F. Gastaldi, F. Tomarelli: General existence theorems for unilateral problems in continuum mechanics, Arch. J. Rational Mech. Anal. 100 (1988) 149–189.https://doi.org/10.1007/BF00282202Google Scholar
  3. A. Beck: On the convexity of a class of quadratic mappings and its application to the problem of finding the smallest ball enclosing a given intersection of balls, J. Global Optim. 39 (2007) 113–126.https://doi.org/10.1007/s10898-006-9127-8Google Scholar
  4. R. I. Bot, S. M. Grad, G. Wanka: Fenchel’s duality theorem for nearly convex functions, J. Optim. Theory Appl. 132 (2007) 509–515.https://doi.org/10.1007/s10957-007-9234-9Google Scholar
  5. R. I. Bot, G. Kassay, G. Wanka: Duality for almost convex optimization problems via the perturbation approach, J. Global Optim. 42 (2008) 385–399.https://doi.org/10.1007/s10898-008-9300-3Google Scholar
  6. W. W. Brecker, G. Kassay: A systematization of convexity concepts for sets and functions, J. Convex Analysis 4 (1997) 109–127.https://doi.org/10.68381/jca04005Google Scholar
  7. S. Deng: Coercivity properties and well-posedness in vector optimization, RAIRO Oper. Research 37 (2003) 195–208.https://doi.org/10.1051/ro:2003021Google Scholar
  8. L. L. Dines: On the mapping of quadratic forms, Bull. Am. Math. Soc. 47 (1941) 494–498.https://doi.org/10.1090/S0002-9904-1941-07494-XGoogle Scholar
  9. F. Flores-Bazán: Existence theory for finite dimensional pseudomonotone equilibrium problems, Acta Appl. Mathematicae 77 (2003) 249–297.https://doi.org/10.1023/A:1024971128483Google Scholar
  10. F. Flores-Bazán: Asymptotically bounded multifunctions and the MCP beyond copositivity, J. Convex Analysis 17 (2010) 253–276.https://doi.org/10.68381/jca17019Google Scholar
  11. F. Flores-Bazán, G. Carcamo: A geometric characterization of strong duality in nonconvex quadratic programming with linear and nonconvex quadratic constraints, Math. Programming A 145 (2014) 263–290.https://doi.org/10.1007/s10107-013-0647-yGoogle Scholar
  12. F. Flores-Bazán, W. Echegaray, F. Flores-Bazán, E. Ocaña: Primal or dual strongduality in nonconvex optimization and a class of quasiconvex problems having zero duality gap, J. Global Optim. 69 (2017) 823–845.https://doi.org/10.1007/s10898-017-0542-9Google Scholar
  13. F. Flores-Bazán, F. Flores-Bazán, C. Vera: Maximizing and minimizing quasiconvex functions: related properties, existence and optimality conditions via radial epiderivatives, J. Global Optim. 63 (2015) 99–123.https://doi.org/10.1007/s10898-015-0267-6Google Scholar
  14. F. Flores-Bazán, N. Hadjisavvas, F. Lara, I. Montenegro: First- and second-order asymptotic analysis with applications in quasiconvex optimization, J. Optim. Theory Appl. 170 (2016) 372–393.https://doi.org/10.1007/s10957-016-0938-6Google Scholar
  15. F. Flores-Bazán, N. Hadjisavvas, C. Vera: An optimal alternative theorem and applications to mathematical programming, J. Global Optim. 37 (2007) 229–243.https://doi.org/10.1007/s10898-006-9046-8Google Scholar
  16. F. Flores-Bazán, F. Opazo: Characterizing the convexity of joint-range for a pair of inhomogeneous quadratic functions and strong duality, Minimax Theory Appl. 1 (2016) 257–290.Google Scholar
  17. G. S. Gowda, J.-S. Pang: Some existence results for multivalued complementarity problems, Math. Oper. Res. 17 (1992) 657–669.https://doi.org/10.1287/moor.17.3.657Google Scholar
  18. N. Hadjisavvas, S. Komlosi, S. Schaible: Handbook of Generalized Convexity and Generalized Monotonicity, Springer, Boston (2005).https://doi.org/10.1007/b101428Google Scholar
  19. N. Hadjisavvas, F. Lara, J. E. Martínez-Legaz: A quasiconvex asymptotic function with applications in optimization, J. Optim. Theory Appl. 180 (2019) 170–186.https://doi.org/10.1007/s10957-018-1317-2Google Scholar
  20. W. M. Hirsch, A. J. Hoffman: Extreme varietes, concave functions, and the fixed charge problem, Comm. Pure Appl. Math. 14 (1961) 355–369.https://doi.org/10.1002/cpa.3160140313Google Scholar
  21. A. Iusem, F. Lara: Second order asymptotic functions and applications to quadratic programming, J. Convex Analysis 25 (2018) 271–291.https://doi.org/10.68381/jca25016Google Scholar
  22. A. Iusem, F. Lara: Optimality conditions for vector equilibrium problems with applications, J. Optim. Theory Appl. 180 (2019) 187–206.https://doi.org/10.1007/s10957-018-1321-6Google Scholar
  23. V. Jeyakumar, G. M. Lee, G. Y. Li: Alternative theorems for quadratic inequality systems and global quadratic optimization, SIAM J. Optim. 20 (2009) 983–1001.https://doi.org/10.1137/080736090Google Scholar
  24. V. Jeyakumar, G. Y. Li: Trust-region problems with linear inequality constraints: exact SDP relaxation, global optimality and robust optimization, Math. Programming A 147 (2014) 171–206.https://doi.org/10.1007/s10107-013-0716-2Google Scholar
  25. V. Jeyakumar, W. Oettli, M. Natividad: A solvability theorem for a class of quasiconvex mappings with applications to optimization, J. Math. Anal. Appl. 179 (1993) 537–546.https://doi.org/10.1006/jmaa.1993.1368Google Scholar
  26. D. Kuroiwa: Convexity for set-valued maps, Appl. Math. Lett. 9 (1996) 97–101.https://doi.org/10.1016/0893-9659(96)00020-1Google Scholar
  27. R. T. Rockafellar: Convex Analysis, Princeton University Press, Princeton (1972).Google Scholar
  28. T. Tanaka: General quasiconvexities, cones saddle points and minimax theorem for vector-valued functions, J. Optim. Theory Appl. 81 (1994) 355–377.https://doi.org/10.1007/BF02191669Google Scholar
  29. H. Tuy, H. D. Tuan: Generalized S-lemma and strong duality in nonconvex quadratic programming, J. Global Optim. 56 (2013) 1045–1072.https://doi.org/10.1007/s10898-012-9917-0Google Scholar
  30. A. F. Veinott, Jr.: Existence and characterization of minima of concave functions on unbounded convex sets, Math. Programming Study 25 (1985) 88–92.https://doi.org/10.1007/BFb0121077Google Scholar
  31. Y. Xia, S. Wang, R. L. Sheu: S-Lemma with equality and its applications, Math. Programming A 156 (2016) 513–547.https://doi.org/10.1007/s10107-015-0907-0Google Scholar

F. Flores-Bazán, N. Hadjisavvas. “Zero-Scale Asymptotic Functions and Quasiconvex Optimization.” Journal of Convex Analysis 26 (2019), No. 4, 1255–1276. https://doi.org/10.68381/jca26066