Previous |  Up |  Next

Article

Keywords:
convex space; $c$-compact set; real Hausdorff topological vector space (t.v.s.); linear operator; locally convex; fixed point; coincidence; zero; upper hemicontinuous (u.h.c.) multifunction
Summary:
Using our own generalization [7] of J.C. Bellenger's theorem [1] on the existence of maximizable u.s.c\. quasiconcave functions on convex spaces, we obtain extended versions of the existence theorem of H. Ben-El-Mechaiekh [2] on zeros for multifunctions with non-compact domains, the coincidence theorem of S.H. Kum [5] for upper hemicontinuous multifunctions, and the Ky Fan type fixed point theorems due to E. Tarafdar [13].
References:
[1] Bellenger J.C.: Existence of maximizable quasiconcave functions on paracompact convex spaces. J. Math. Anal. Appl. 123 (1987), 333-338. MR 0883692 | Zbl 0649.46006
[2] Ben-El-Mechaiekh H.: Zeros for set-valued maps with non-compact domains. C. R. Math. Rep. Acad. Sci. Canada 12 (1990), 125-130. MR 1070423 | Zbl 0734.47028
[3] Ky Fan: Some properties of convex sets related to fixed point theorems. Math. Ann. 266 (1984), 519-537. MR 0735533 | Zbl 0515.47029
[4] Jiang J.: Fixed point theorems for paracompact convex sets. Acta Math. Sinica 4 (1988), 64-71. MR 0953351 | Zbl 0715.54032
[5] Kum S.H.: Ph.D. Dissertation, Seoul National University, 1991.
[6] Lassonde M.: On the use of KKM multifunctions in fixed point theory and related topics. J. Math. Anal. Appl. 97 (1983), 151-201. MR 0721236 | Zbl 0527.47037
[7] Park S., Bae J.S.: Existence of maximizable quasiconcave functions on convex spaces. J. Korean Math. Soc. 28 (1991), 285-292. MR 1127833 | Zbl 0756.47050
[8] Park S.: Applications of maximizable linear functionals on convex sets. ``Proc. in Honor of C. N. Lee'', 537-548, 1991.
[9] Park S.: Fixed point theory of multifunctions in topological vector spaces. J. Korean Math. Soc. 29 (1992), 191-208. MR 1157308 | Zbl 0758.47048
[10] Park S.: Generalized matching theorems for closed coverings of convex sets. Numer. Funct. Anal. and Optimiz. 11 (1990), 101-110. MR 1058779 | Zbl 0706.52001
[11] Shih M.-H., Tan K.-K.: Covering theorems of convex sets related to fixed-point theorem. in ``Nonlinear and Convex Analysis (Proc. in Honor of Ky Fan)'' (B.-L. Lin and S. Simons, eds.), 235-244, Marcel Dekker, Inc., New York, 1987. MR 0892795
[12] Simons S.: On existence theorem for quasiconcave functions with applications. Nonlinear Anal. TMA 10 (1986), 1133-1152. MR 0857745
[13] Tarafdar E.: An extension of Fan's fixed point theorem and equilibrium point of an abstract economy. Comment. Math. Univ. Carolinae 31 (1990), 723-730. MR 1091369 | Zbl 0745.47046
Partner of
EuDML logo