in this note we characterize the compact weighted frobenius-perron operator $p$ on $l^1(sigma)$ and determine their spectra. we also show that every weakly compact weighted frobenius-perron operator on $l^1(sigma)$ is compact.

In this paper we study date dependence for a delay equation which models a business cycle. The study is made using weakly Picard operators. 2000 Mathematical Subject Classification: 34K05, 47H10

We investigate the sufficient condition under which each positive b-weakly compact operator is Dunford-Pettis. We also investigate the necessary condition on which each positive b-weakly compact operator is Dunford-Pettis. Necessary condition on which each positive b-weakly compact operator is weakly compact is also considered. We give the operator that is semi-compact, but it is not bweakly. W...

In this short note, we propose a fixed point theorem in the setting of Banach space without using Picard operator.