تصمیم گیری های تعیین اندازه دسته تولید برای موارد رو به وخامت گذاشته با دو انبار تحت فرمان وابسته به اندازه اعتباری تجارت
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|22799||2012||14 صفحه PDF||سفارش دهید||15676 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : International Journal of Production Economics, Volume 137, Issue 1, May 2012, Pages 102–115
This study attempts to determine economic order quantity for deteriorating items with two-storage facilities (one is an owned warehouse and the other is a rented warehouse) where trade credit is linked to order quantity. As assumed herein, payment delays depend on the quantity ordered, when the order quantity is less than that at which a payment delay is permitted, the payment for the items must be made immediately. Otherwise, the fixed trade credit period is permitted. Furthermore, if the order quantity exceeds the owned warehouse capacity, it will be necessary to rent a warehouse which results in an additional rental cost. Otherwise, renting a warehouse is unnecessary. The problem discussed in this study involves how retailers decide whether to rent an additional warehouse to hold more items and thus obtain a trade credit period. First, a deterministic inventory model is developed for deteriorating items under the above situation. Second, this study demonstrates that the total cost function per unit time is convex via a rigorous proof. Third, five theorems are developed to optimize the replenishment cycle time and the order lot-size. Finally, numerical examples are used to illustrate these theorems and sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out and some important managerial insights are obtained.
In recent decades, many studies have examined the problem of managing deteriorating items including medicines, volatile liquids, blood banks, foodstuffs and electronic components. Raafat (1991) presented a complete survey of the inventory literature on deteriorating inventory models. Moreover, Ghare and Schrader (1963) the first proponents proposed for developing a revised form of the EOQ model that assumed exponential decay. Covert and Philip (1973) then extended this model to consider the Weibull distribution deterioration. Other noteable works in this include those of Dave and Patel (1981), Sachan (1984), Hariga (1996) and their references. Recently, Goyal and Giri (2001) presented a review of the inventory literature published on deteriorating items since the early 1990s. The conventionally adopted EOQ model assumes that the retailer must pay to purchase the item immediately upon receiving it from a supplier. However, such an assumption does not necessarily reflect the scenario in the real world. In fact, suppliers generally allow retailers' access to forward financing to increase demand or decrease inventory. This means that the supplier permits a trade credit period for the settlement of payment. The effect of the trade credit on the optimal inventory model has been examined in various studies. Goyal (1985) established an inventory model under permissible delay in payments. Shah, 1993a and Shah, 1993b designed EOQ models for perishable items where payment delay is permissible. Other noteable works on this area were by Chand and Ward (1987), Aggarwal and Jaggi (1995), Chung and Liao (2006), Jamal et al. (2000), Chung (1998), Daellenbach (1986), Shinn (1997), Shinn and Hwang (2003), Liao, 2007a and Liao, 2007b, Zaid (2011), Ruo et al. (2011), Musa and Sani (2011), Tsao and Sheen (2012) and others. In fact, a key finding of these studies was that EOQ is independent of trade credit. Chung and Liao (2004) and Chang et al. (2003) considered the deteriorating items given the conditions of an order-size-dependent trade credit. All the aforementioned inventory models implicitly assumed that the retailer owns a single warehouse with unlimited capacity. However, in more practical terms, any warehouse has a limited capacity. On the other hand, due to some reasons such as an attracted price discount for bulk purchase, the order costs higher than one using rented warehouse, and so on, inventory managers usually are attracted to hold more items than can be stored in an owned warehouse. From this perspective, the two warehouse inventory models recently have been considered by various authors. This kind of system was first proposed by Hartely (1976). Sarma (1983) designed a deterministic inventory model with infinite replenishment rate and two storage levels. Furthermore, Murdeshwar and Sathe (1983) extended the case to incorporate finite replenishment rate. Other researchers that have studied in this area include Goswami and Chaudhuri (1992), Bhunia and Maiti (1998), Sarma (1987), Pakkala and Achary, 1992a and Pakkala and Achary, 1992b, Benkherout (1997), Zhou (1998), Yang (2004) and Zhou and Yang (2005). Due to the factors mentioned above, Chung and Huang (2006) considered a two-warehouse inventory problem for deteriorating item with limited storage space under permissible delay in payments. However, in certain practical situations, trade credits can be applied as an alternative to price discounts to order more quantities. Consequently, an important problem associated with inventory maintenance is deciding whether to rent an additional warehouse to hold more items to obtain a trade credit period. Based on the above arguments, this study incorporates both Chung and Huang (2006) and Chung and Liao (2004) under above conditions. This study considers payment delay to depend on order quantity where the order quantity is less than that at which delayed payment is permitted, meaning payment must be made immediately. Otherwise, the fixed trade credit period is permitted. Additionally, if the order quantity exceeds owned warehouse capacity it becomes necessary to rent a warehouse which results in an additional rental cost. Given this marketing situation, this study develops a deterministic inventory model for deteriorating items with two warehouses (one is OW and the other is RW) and where trade credit is linked to order quantity. This study then demonstrates easy-to-use theorems to identify the optimal replenishment cycle time and the optimal order lot-size to minimize. Numerical examples are used to illustrate all of the study theorems and revealed the decision whether to rent an additional warehouse. Finally, sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out and some important managerial insights are obtained.
نتیجه گیری انگلیسی
This study combines the work of Chung and Liao (2004) and Chung and Huang (2006) to optimize ordering policy for a deteriorating commodity under capacity constraint when trade credit is linked to ordering quantity, a situation designed to reflect real world business situations. Using Theorem 2, Theorem 3, Theorem 4, Theorem 5 and Theorem 6, the decision-maker can easily determine whether it will be financially advantageous to rent a warehouse to hold much more items to obtain a trade credit period. In fact, in situations involving unlimited storage space, the inventory model discussed in this study becomes identical to that considered by Chung and Liao (2004). Finally, numerical examples are used to illustrate all of the study results. From the sensitivity analysis, we can see that the ordering cost, deterioration rate and demand rate cost affect the total cost of the retailer.