Mehmet Barut

Measuring supply chain coupling: an information system perspective

Supply chain management often requires the integration of inter-and-intra organizational relationships and coordination of different types of flows within the entire supply chain structure. Inter-company integration and coordination via information technology has become a key to improved supply chain performance. Recent advances in information technology enable firms to effectively and inexpensively manage the coordination of not only the physical flow of materials but also the flow of different types of information such as demand, capacity, inventory, and scheduling, through a supply chain. Despite its importance, little attention has been given in the literature to the issue of measuring the magnitude and the effectiveness of available information that logistics information systems provide. This study provides a generic measure to show how well or to what degree a firm is integrated or “coupled” with the members of its supply chain structure from information flow system perspective. The measure, called Degree of Supply Chain Coupling (DSCC), is a 2-tuple index which takes into account both the intensity and extent to which information about demand, capacity, inventory, and scheduling is shared and used by the firm in both direction of the supply chain. We indicate several productive practical uses of the DSCC measure at both macro and micro levels.

Revenue Management in Order‐Driven Production Systems

This article investigates the effectiveness of a tactical demand-capacity management policy to guide operational decisions in order-driven production systems. The policy is implemented via a heuristic that attempts to maximize revenue by selectively accepting or rejecting customer orders for multiple product classes when demand exceeds capacity constantly over the short term. The performance of the heuristic is evaluated in terms of its ability to generate a higher profit compared to a first-come-first-served (FCFS) policy. The policies are compared over a wide range of conditions characterized by variations in both internal (firm) and external (market) factors. The heuristic, when used with a Whole Lot order-processing approach, produces higher profit compared to FCFS when profit margins of products are substantially different from each other and demand exceeds capacity by a large amount. In other cases it is better to use the heuristic in conjunction with the Split Lot order-processing approach.

An ant colony optimization algorithm for load balancing in parallel machines with sequence-dependent setup times

This study introduces the problem of minimizing average relative percentage of imbalance (ARPI) with sequence-dependent setup times in a parallel-machine environment. A mathematical model that minimizes ARPI is proposed. Some heuristics, and two metaheuristics, an ant colony optimization algorithm and a genetic algorithm are developed and tested on various random data. The proposed ant colony optimization method outperforms heuristics and genetic algorithm. On the other hand, heuristics using the cumulative processing time obtain better results than heuristics using setup avoidance and a hybrid rule in assignment.

Design and evaluation of a dynamic capacity apportionment procedure

Deploying a decision theory based approach; we develop a heuristic for short-term constrained capacity allocation to multiple-product classes in make-to-order manufacturing, attempting to maximize profit by discriminating between product classes. Efficacy of the heuristic is evaluated by comparing its performance to a base case and an upper bound, under a wide variety of operational conditions such as variations in profit attractiveness, capacity tightness, customer order size structure, customer order rate structure and demand coefficient of variation, considering three different scenarios of time-variant order rate of products. The results indicate that the heuristic is effective in obtaining increased profit when capacity is very tight and products are well differentiated. On average it yields an increase of 9.38% in total profit with a concomitant decrease of 0.85% in capacity utilization. The results of this study serve to highlight the value of proactively seeking to differentiate products, particularly when demand exceeds capacity.

RFID and Corporate Responsibility: Hidden Costs in RFID Implementation

No abstract available.

A Neuro-Genetic Approach to Design and Planning of a Manufacturing Cell

In this paper, we propose a neuro-genetic decision support system coupled with simulation to design a job shop manufacturing system by achieving predetermined values of targeted performance measures such as flow time, number of tardy jobs, total tardiness and machine utilization at each work center. When a manufacturing system is designed, the management has to make decisions on the availability of resources or capacity, in our setting, the number of identical machines in each work station and the dispatching rule to be utilized in the shop floor to achieve performance values desired. Four different priority rules are used as Earliest due date (EDD), Shortest Processing Time (SPT), Critical ratio (CR) and First Come First Serve (FCFS). In reaching the final decision, design alternatives obtained from the proposed system are evaluated in terms of performance measures. An illustrative example is provided to explain the procedure.

Measuring Supply Chain Relationships: A Social Network Approach

Achieving excellence in global supply chain performance usually requires firms to develop close connections and relationships with other parties in the chain. Today it is critical to evaluate, reengineer and manage these relationships properly. Drawing from social network analysis, this study presents a set of measures for a focal company and its relationships. These measures could be useful for practicing managers in designing and managing multiple relationships in a supply chain.

Commodity Bundling in the Supply Chain: A Simulation Study

Commodity bundling has received little attention in the supply chain literature although products in a bundle are delivered through supply chains. Marketing and economics literature largely discuss the issue from pricing and consumer behaviour perspectives. In this study, we investigate bundling strategy from a supply chain and operations standpoint. Our results indicate that not only the products in the bundle but also the supply chains providing these products should be matched considering capacity limitations and volume flexibilities. We discuss theoretical implications of our results and provide recommendations for practicing managers based on our findings and insights.

A global learning experience in supply chain logistics management

Global competition created multinational supply chains where raw materials from different countries are manufactured in a country, marketed in another, and consumed by consumers in different countries so that cost-effective production and higher customer service levels can be achieved by taking a systems approach to supply chain management. Therefore, a key to successful management is acquaintance with interdisciplinary and multicultural environments and utilization of communication technologies. In this research, a global teaching framework for industrial engineering and business students is developed and evaluated.

Effectiveness of capacity rationing heuristics in make to order environment

This paper investigates the effectiveness of a dynamic capacity-rationing heuristic for order acceptance and rejection in a capacitated make-to-order manufacturing environment. The heuristics developed for managing capacity has been shown to work better than accepting orders on a first-come, first-served basis. However, realised effectiveness versus potential effectiveness with respect to optimum has not been investigated. Results of this study reveal that the rationing heuristic is very effective in yielding results in proximity of optimum solution when customer segments are very distinct or highly differentiated and when implied utilisation is very high. On the other hand, when the attractiveness of higher profitable customer segment diminishes and capacity is not tight there is a significant potential to improve the heuristic.