A Multi-Periodic Multi-Product Inventory Control Problem with Discount: GA Optimization Algorithm

In this article, a finite horizon, multi product and multi period economic order quantity like seasonal items is considered where demand rate is deterministic and known but variable in each period. The order quantities of items come in batch sizes and the end of the period order quantity and, consequently, demand of customers are zero. In addition, storage space is constrained and the problem was considered under all units discount (AUD) policy. The modeling technique used for this problem is mixed binary integer programming. The objective was to find the minimization optimal order quantities under time value of money over the finite horizon. The inventory control system costs include three costs: ordering cost, holding cost, and purchase cost. In order to solve the proposed model, a genetic algorithm (GA) is applied. Finally, we provide a number of examples in order to illustrate the algorithms further

Modeling a bi-objective newsboy problem with compound discount condition, considering Warehouse space and budget constraints and solving it by different approaches of MODM problems

The newsboy problem is considered as a single period problem which is very common in our real life. This paper study the newsboy problem considering the discount constraint including quantity and incremental and also warehouse space and budget constraint with two objectives of profit and service level maximizing. These objectives are designed by an integer non - linear model. This model is solved by using GAMS software and various multi-objective techniques considering this assumption that each product distribution is uniform. Also comparison of methods has been done in tow forms of statistical comparison and multiple decisions

Modeling and Solving a Blood Supply Chain Network: An approach for Collection of Blood

Management of the blood as a vital and scarce resource is very important. The aim of this research is to present a novel mathematical model for designing a reliable blood supply chain network. This network consists of three main echelons including donors, collection facilities and demand points. At the collection echelon, three types of facilities are considered for receiving the bloods from the donors: main blood centers (MBCs), demountable collection centers (DCCs), and mobile blood facilities (MBFs). DCCs, and MBFs are mobile facilities that don’t have a permanent location and always move from a location to another one for collecting the bloods from the donors. The main difference between the MBFs and DCCs is that the DCCs can only visit at most a candidate location every period, but the MBFs can visit more than one candidate location in every period. Also, there is differences between their capacities and their costs. Both of DCCs and MBFs dispatch the collected bloods to the MBCs that are permanent facilities and are responsible for receiving the bloods and performing the blood transfusion process and finally sending the bloods to the demand points. Using a numerical example, the applicability of the proposed network is analyzed

Reducing the cost of wastage and shortage of hospitals' blood products with regard to the compatibility of blood groups

Reducing the cost of wastage and shortage of hospitals' blood products with regard to the compatibility of blood groups Blood supply chain management is considered one of the main components of the health system of each country. This chain consists of two-component blood collection and supply of products for blood donors has been formed. This article focuses on the issue of the supply of blood products; that tries to provide a mathematical model to reduce waste costs and a shortage of blood products to hospitals. In this model, while meeting the needs of different groups of hospitals, blood in hospitals is minimized inventory costs. A mathematical model in five hospitals affiliated Blood Transfusion Center of East Azerbaijan is implemented. With regard to the compatibility of blood groups and red cell products supply costs and inventory decreased 18% o + blood group also declined to be compatible with other blood types. Keywords: blood supply chain, RBC, compatibility, BT

Measurement and comparison of industrial infrastructure of SMEs among Iranian provinces

The creation of small manufacturing enterprises is considered by many governments and donor agencies, as the key to economic and social development in countries regardless of development level. Furthermore, review of the literature show evidence that SMEs are understood as a source of technology development. At the same time they are vulnerable to a number of restrictions such as access to finances, skilled labor, public support and suffer from survival rate problems. First, this research aims to shed lights on the role that small manufacturing enterprises play in the process of industrial and economic development across provinces of Iran. Second, the status of industrial infrastructure is investigated. The data is used to estimate parametrically and non-parametrically a number of composite infrastructure indices to investigate the capacity, resource, education, credit and capital assets components. Finally based on the findings, lessons and conclusion, guidelines for policy formulation will be suggested. For our study, use of sub-indices and a new composite of Development Infrastructure Index (DII) can help provinces to evaluate their status of industrial infrastructure

A geometric programming approach for a vendor managed inventory of a multiretailer multi-item EPQ model

Due to the uncertain situations of the world, considering inventory management in a stochastic environment gains a lot of interest. In this paper, we propose a multi-item economic production quantity (EPQ) model with a shortage for a single-vendor, multi-retailer supply chain under vendor managed inventory (VMI) policy in a stochastic environment. Three stochastic constraints are developed in the model. Geometric programming (GP) approach is employed to find the optimal solution of the nonlinear stochastic programming problem to minimize the mean-variance of the total inventory cost of the system. Since the problem is in the Signomial form, first, an algorithm is used to convert the model into the standard GP form. The performance of the addressed model and the solving method are evaluated based on computational experiments and sensitivity analysis. A case study in an Iranian furniture supply chain is conducted to show the applicability of the proposed model and 17.78% improvement in terms of total cost is gained