Kurdistan Region-Iraq Ministry of Higher Education and Scientific Research University of Duhok College of Basic Education Nets and Filters in Topological Space Prepared by Mahmoud Ahmed Yousef B.Sc. Mathematics / College of Education for pure sciences / University of Kerbala ( 2013 ) Supervised by Prof. Dr. Alias B. Khalaf 2020 A.D 2720 K. 1441 A.H