In this thesis, a deterministic inventory model under cyclic demand which decreases within a cycle is considered to find the times at which orders should be placed, and the order quantities which minimize the total cost per demand cycle.
Studies were undertaken with respect to the following three problems for both discrete and continuous demand pattern.
1) The method to determine finite planning horizon or infinite planning horizon was developed.
2) For finite planning horizon, three models ((t, $m_n$) model, ($t_n$, m) model and ($t_n$, $m_n$) model) were developed.
3) For infinite planning horizon the methods to determine the order quantities with and without taking into account of the expected interest, inflation and stoppage of demand were developed.
