REVIEW OF LITERATURE ON VARIOUS FACTORS AFFECTING INVENTORY POLICY (original) (raw)
Review of Literature and Survey of the Developed Inventory Models
2018
The review of the literature is an important feature of the research work that connects the past work with the current work. The literature on the inventory modelling is growing quickly. The goal of this article is to present a complete and updated information about the developed inventory models under different situations.
Inventory models with managerial policy independent of demand
European Journal of Operational Research, 2011
This paper is an extension of two papers. The first of these, published in European Journal of Operational Research, 2007, 112-120 is by Deng et al. (2007) and concerns inventory models for deteriorating items with ramp type demand. The second, published in Computer & Industrial Engineering, 2009, 1296-1300 is by Cheng and Wang (2009) and concerns inventory models for deteriorating items with trapezoidal type demand. The purpose of this paper is threefold. First, this paper will show that the optimal solution is independent of the demand considered in the two previous papers. Second, several replenishment cycles were considered during the finite time horizon, to balance the setup cost with the sum of the deteriorated cost, holding cost, and shortage cost. Third, this paper will examine the same numerical example in Cheng and Wang (2009) to show that this new approach will result in the saving of 84.39%.
Inventory Control Models and Methods
Inventory control is a major field in OR. Interest in the problems of optimal stock management at a scientific level goes back to the start of the 20th century. The most important impulse, however, came after the 2nd World War when scientists of the caliber of Jacob, Marschak, Kenneth Arrow, Samuel Karlin among others looked into the problem of optimal stocking under stochastic demand. It was characteristic of this discipline, that methods of solving problems of this type were developed first before the necessary commercial electronic data processing for their ready application were available.
An integrated production–distribution model for a deteriorating inventory item
International Journal of Production Economics, 2011
We develop an integrated production-distribution model for a deteriorating item in a two-echelon supply chain. The supplier's production batch size is restricted to an integer multiple of the discrete delivery lot quantity to the buyer. Exact cost functions for the supplier, the buyer and the entire supply chain are developed. These lead to the determination of individual optimal policies, as well as the optimal policy for the overall, integrated supply chain. We outline a procedure for determining the optimal supply chain decisions with the objective of minimizing the total system cost. Our approach is illustrated through a numerical example.
The fundamental reason for carrying inventories is that it is physically impossible and economically impractical for each stock item to arrive exactly where it is needed exactly when it is needed. The goal of inventory management is to ensure the consistent delivery of the right product in the right quantity to the right place at the right time. Most of the researchers in inventory system were directed towards non-deteriorating products. However, there are certain substances, whose utility do not remain same with the passage of time. Deterioration of these items plays an important role and items cannot be stored for a long time. Deterioration of an item may be defined as decay, evaporation, obsolescence, loss of utility or marginal value of an item that results in the decreasing usefulness of an inventory from the original condition. When the items of the commodity are kept in stock as an inventory for fulfilling the future demand, there may be the deterioration of items in the inventory system, which may occur due to one or many factors i.e. storage conditions, weather conditions or due to humidity. INTRODUCTION Most of the inventory models were formulated in a static environment where the demand is assumed to be constant and steady. In fact, the constant demand assumption is only valid dur ing the maturity phase of time. In realistic business situations many items of inventory such as electronic products, fashionable clothes, tasty food products and domestic goods generate increasing sales after gaining consumer " s acceptance. Therefore it is more realistic if we consider demand rate as time dependent. Many businesses are not as successful as they could be simply because they lack the know-how or the will to implement sound inventory management and control practices. Successful inventory is a compromise between low inventory levels and meeting targeted fill rates. Investing in the right inventory and reducing excess will improve customer fill rates, inventory turnover and cash flow and profits. The purpose of the study is to develop and analyze some inventory models for decaying items with variable demand rates for different realistic business situations.
Literature Review on Shortage Cost Modeling in Inventory Management
Proceedings of the 8th International Conference on Operations Research and Enterprise Systems, 2019
In this article, we emphasize on one hand the importance of quantifying the shortage cost in order to measure the optimal parameters for any selected inventory policy and thus enhance the performance of the supply chain and on the other hand the complexity of doing so. Then, we provide a detailed literature review of the existing various models for quantifying the shortage cost in an inventory management context along with a classification of this literature under three categories: Theoretical descriptive models, empirical approaches and simulation based models. Finally, we point out some gaps in this literature such as the lack of continuity of research in this field and the absence of generic fairly easy to apply but accurate methods and we suggest a few future perspectives.
Inventory Management at the Enterprise in the Field of Probability Models
Scientific Horizons, 2021
The inventory management system is designed to continuously ensure the production activities of the enterprise with all necessary resources. The purpose of this study is to build a probabilistic model that can be proposed as a new inventory model, which establishes the relationship of period factors between the purchase of parts and the duration of their suitability, which affect inventory management. The research methods are based on a probabilistic approach using continuous distributions. Using the statistical method, point estimates were found for the studied parameters: mean and standard deviation. The histograms of relative frequencies between dates of two next purchases, volume of purchases of details and days of replacement of the fulfilled details are constructed. The critical areas for the studied parameters are illustrated. The values of the difference in days between the purchases of parts and the values of purchases of parts that meet the normal distribution of random va...
Technical Note on Inventory Model with Defective Items
Abstract and Applied Analysis, 2010
Under a reasonable assumption, we derive an analytical approach that verifies uniqueness of the optimal solution for stochastic inventory models with defective items. Our approach implies a robust method to find the optimal solution.
A note on two inventory models
Bulletin of the Belgian Mathematical Society, Simon Stevin
In inventory models the major objective consists of minimizing the total inventory cost and to balance the economics of large orders or large production runs against the cost of holding inventory and the cost of going short. In the present paper we analyse the uctuations in the stock and starting from some basic assumptions we obtain bounds between which the stock varies. The main purpose and use of our results is that we are able to determine the exact upper and lower stockbounds. In the paper we formulate a deterministic and a stochastic version of our model.
A report of research on inventory models
Engineering Costs and Production Economics, 1983
ABSTRACT The objective of this paper is to describe the steps in and results of current research carried out within the framework of a special long-term project supervised and financed by the Hungarian Academy of Sciences. Since the research, which started in 1976, will go on for several more years — and so we are far from final results — this paper is mostly of an informative nature, intended to make known the ideas behind our work and the progress of our research.