Number Of Replenishment Cycles Research Articles

Analysis of credit linked demand in an inventory model with varying ordering cost.

In this paper, we have considered an economic order quantity model for deteriorating items with two-level trade credit policy in which a delay in payment is offered by a supplier to a retailer and also an another delay in payment is offered by the retailer to his/her all customers. Here, it is proposed that the demand function is dependent on the length of the customer’s credit period and also the duration of offering the credit period. In this article, it is considered that the retailer’s ordering cost per order depends on the number of replenishment cycles. The objective of this model is to establish a deterministic EOQ model of deteriorating items for the retailer to decide the position of customers credit period and the number of replenishment cycles in finite time horizon such that the retailer gets the maximum profit. Also, the model is explained with the help of some numerical examples.

Fuzzy Economic Order Quantity (FEOQ) Model with Units Lost Due to Deterioration

This model investigates the instantaneous fuzzy economic order quantity model by allocating the percentage of units lost due to deterioration in an on-hand inventory by framing variable ordering cost. The objective is to maximize the fuzzy net profit so as to determine the order quantity, the cycle length and number of units lost due to deterioration in fuzzy decision space. For any given number of replenishment cycles the existence of a unique optimal replenishment schedule are proved and mathematical model is developed to find some important characteristics for the concavity of the fuzzy net profit function. Numerical examples are provided to illustrate the results of proposed model which benefit the retailer and this policy is important, especially for wasting of deteriorating items. Finally, sensitivity analyses of the fuzzy optimal solution with respect to the major parameters are also studied.

Supplier–buyer deterministic inventory coordination with trade credit and shelf-life constraint

The purpose of the paper is to formulate a collaborative mechanism for optimising the replenishment schedule under trade credit and shelf-life constraint in a two-echelon supply chain. We first derive the necessary and sufficient conditions to obtain the optimal replenishment policy for the non-integrated and collaborative scenarios, respectively. Then, for additional cost savings realised from coordination, we focus on discussing how to determine the equitable trade credit period, and propose an efficient solution procedure to determine the optimal replenishment schedule and coordination results. Finally, two industrial examples are used to illustrate the proposed strategy and algorithm, and the sensitivity analysis of the optimal result with respect to major parameters is presented. The sensitivity analysis suggests that the number of replenishment cycles is optimal in almost all cases under coordination and the buyer's savings in percentage is much greater than the supplier's savings in percentage. The major contribution of the paper is that we incorporate shelf-life into supply chain coordination with trade credit. In real-life situations, this proposed strategy may be applied in shelf-life products.

Economic order quantity models for deteriorating items and partial backlogging when demand is quadratic in time

In this paper, we extend the inventory lot-size model introduced in Ghosh and Chaudhuri (2006) to allow for partial backlogging. In addition, we also relax their assumptions of equal replenishment cycles and constant shortage lengths. For any given number of replenishment cycles, we show that the optimal replenishment schedule exists uniquely. We then prove that the total relevant cost is a convex function of the number of replenishments. Consequently, we propose an algorithm to find the optimal replenishment number and schedule. Finally, we run several numerical examples, and obtain some managerial implications by using sensitivity analyses. [Received 18 November 2009; Revised 18 February 2010; Revised 27 April 2010; Accepted 28 April 2010]

A note on finite replenishment inventory systems with continuous deterministic demand

Abstract The necessary and sufficient conditions are derived for determining the optimal number of replenishment cycles and their start times in a deterministic continuous-time finite replenishment inventory model with a finite planning horizon. The differences between this model and its instantaneous replenishment counterpart are pointed out. It is shown that an optimal solution can always be found when the number of replenishment cycles is preset, the demand function is increasing and the replenishment rate is sufficiently large. It is also shown that when the number of replenishment cycles is unspecified, the problem can be solved by first determining the optimal cycle start limes for a given number of cycles m and then optimizing over m.