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Evolving production technologies are altering the cost structures on which many supporting inventory ordering systems are based; for example, fixed costs compared with variable costs are increasing significantly. Unfortunately, many inventory ordering formulations consider only the variable portions of inventory ordering costs and inventory holding costs. To address this deficiency, departs from traditional categorizations and offers an inventory classification schema based on the functional roles served by the inventory items. Functional roles of inventory include transition, buffer, investment, maintenance, supplies and dead stock. Extending the schema, assesses the implications each functional role has for inventory cost containment, emphasizing the impact of evolving production technologies on inventory ordering policies and their relevance to functional roles.

This paper seeks to construct a model for inventory management for multiple periods. The model considers not only the usual parameters, but also price quantity discount, storage and batch size constraints.

Mixed 0‐1 integer programming is applied to solve the multi‐period inventory problem and to determine an appropriate inventory level for each period. The total cost of materials in the system is minimized and the optimal purchase amount in each period is determined.

The proposed model is applied in colour filter inventory management in thin film transistor‐liquid crystal display (TFT‐LCD) manufacturing because colour filter replenishment has the characteristics of price quantity discount, large product size, batch‐sized purchase and forbidden shortage in the plant. Sensitivity analysis of major parameters of the model is also performed to depict the effects of these parameters on the solutions.

The proposed model can be tailored and applied to other inventory management problems.

Although many mathematical models are available for inventory management, this study considers some special characteristics that might be present in real practice. TFT‐LCD manufacturing is one of the most prosperous industries in Taiwan, and colour‐filter inventory management is essential for TFT‐LCD manufacturers for achieving competitive edge. The proposed model in this study can be applied to fulfil the goal.

The purpose of this paper is to study integrated inventory system and pricing and ordering strategy for vendor‐buyer supply chain system. Here, the vendor offers a trade credit to the buyer when the buyer's order quantity exceeds a given pre‐specified quantity. Therefore, to incorporate the concept of vendor‐buyer integration and trade credit linked, the authors analyze the model to determine the optimal strategy for an integrated vendor‐buyer inventory system under the condition of credit linked to the order quantity when demand is quadratic.

A mathematical model for integrated inventory system is developed when demand rate is increasing function of the time and decreasing function of the retail price. By analyzing the total channel profit function, the authors developed some useful results to characterize the optimal solution and provide an iterative algorithm to find the retail price, buyer's order quantity and the number of shipments per production run from the vendor to the buyer.

By developing a solution algorithm, the optimal retail price, order quantity and number of shipments from the vendor to the buyer are provided. Numerical examples and sensitivity analyses are presented to validate the proposed model. Through extensive numerical analyses, it is observed that a longer credit term increases profits of the player for the entire supply chain. The vendor should establish the threshold for allowing trade credit comprehensively to ensure the greatest benefit for both players.

Most of the research articles available in the literature considered the constant demand or linearly changing demand. In this paper, a mathematical model is developed considering time dependent quadratic demand. Very few researchers have investigated joint optimal policy in vendor‐buyer supply chain system, considering trade credit is linked to order quantity, and still there are not many findings on the benefit of integrated policy and trade credit.

Examines the reasons driving French food retailers to build major speculative inventories through forward buying from their suppliers. First analyses the origin of the phenomenon and its strategic basis. Then, using the model of postponement‐speculation proposed by Louis Bucklin in the mid‐1960s, explains why forward buying does not conflict with a reduction of in‐store inventories. Finally, offers comments on the future of speculative inventories in the French context, which is characterized by permanently conflicting relations between manufacturers and distributors. To do so, reference is made to information collected in the course of interviews with the logistics managers of ten of the leading companies in the sector.

A production‐inventory system based on a model proposed by Axsäter is examined with the purpose of understanding the dynamic properties of the model.

The information flow concept is discussed and a dynamic analysis using a system simplification approach is carried out to achieve an understanding of the dynamic behaviour of the system. Finally, the information flow is examined and analysed from a hierarchical perspective.

The model is extended to include an order decision rule and a production unit and it is shown that the extended model has the capability to represent the dynamics of a number of different system management principles. The three different model instances of base stock, kanban and material requirements planning character are analysed.

Dynamic modelling of production‐inventory and supply chain models are usually analysed at an aggregate level not involving any complex relations of materials or capacities. In this paper, this line of research is merged with an approach based on multiple information channels using matrix representation and it is shown how a system simplification approach can be used for this purpose.

As a just‐in‐time (JIT) ordering system for multi‐stage production inventory systems, both the kanban system and its alternative, the concurrent ordering system, have been proposed. For both JIT ordering systems, the reactive JIT ordering systems that adjust the buffer size responding to unstable changes in demand were proposed. In addition to the adjustment of buffer size, switching ordering systems between the kanban system and the concurrent ordering system is proposed in order to realize agile control in JIT ordering systems. In the proposed system, the time series data of demand is monitored, and switching the order release systems and adjusting the buffer size are considered when an unstable change in demand is detected with the exponentially weighted moving average charts. The effectiveness of the proposed system is analyzed using simulation experiments under unstable conditions. From these simulation experiments, it is clear that the proposed system can react to unstable changes in demand and satisfy the required level for the mean waiting time of demand. Also, to attain the required level, the proposed system must possess much less work‐in‐process inventories than the previous systems which adjust only the buffer size and do not switch ordering systems.

Key components of the logistics mix are described in an effort to create an understanding of the total logistics concept. Chapters include an introduction to logistics; the strategic role of logistics, customer service levels, channel relationships, facilities location, transport, inventory management, materials handling, interface with production, purchasing and materials management, estimating demand, order processing, systems performance, leadership and team building, business resource management.

Organisations either keep spares for their own use, or‐for‐sale to other organisations. In either case, the ultimate need is to be able to replace worn or defective parts in operational machinery or equipment. In an economic sense, spares are kept to meet the needs of the situation in the cheapest way.

Considers a multi‐stage multi‐product production, inventory and transportation system including lot production processes and develops a mathematical model for a pull type ordering system. The decision variables of the presented model are initial ordering quantities and the objective is to minimize the sum of the replenishment level at each inventory point. The model is formulated as an integer programming problem, and an approximate procedure is proposed to obtain a near optimal solution in short time using a mathematical programming package. Finally, shows a numerical example of the model applied to an actual manufacturing system of an automobile parts manufacturer in order to verify the effectiveness of the solution procedure and to clarify the applicability of the modelling approach.

Deals with the kanban system in just‐in‐time (JIT) production as a system of production planning and inventory control for multi‐stage production inventory systems, Constructs a queueing network model of the kanban system with SLAM II. Aims to improve the kanban system by modifying the flow of information. Because the orders for all stages are released concurrently, the modified system is called the concurrent ordering system. By means of simulation experiments, investigates and compares the performances of the models.