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Full-Text Articles in Business
Issues In Disaster Relief Logistics, Nezih Altay
A Comparative Study Of Modeling And Solution Approaches For The Coordinated Lot-Size Problem With Dynamic Demand, Li-Lian Gao, Nezih Altay, Powell Robinson
A Comparative Study Of Modeling And Solution Approaches For The Coordinated Lot-Size Problem With Dynamic Demand, Li-Lian Gao, Nezih Altay, Powell Robinson
Nezih Altay
In the coordinated lot-size problem, a major setup cost is incurred when at least one member of a product family is produced and a minor setup cost for each different item produced. This research consolidates the various modeling and algorithmic approaches reported in the literature for the coordinated replenishment problem with deterministic dynamic demand. For the two most effective approaches, we conducted extensive computational experiments investigating the quality of the lower bound associated with the model’s linear programming relaxation and the computational efficiency of the algorithmic approaches when used to find heuristic and optimal solutions. Our findings indicate the superiority …
Exact And Heuristic Solution Approaches For The Mixed Integer Setup Knapsack Problem, Nezih Altay, Powell Robinson, Kurt Bretthauer
Exact And Heuristic Solution Approaches For The Mixed Integer Setup Knapsack Problem, Nezih Altay, Powell Robinson, Kurt Bretthauer
Nezih Altay
We consider a class of knapsack problems that include setup costs for families of items. An individual item can be loaded into the knapsack only if a setup cost is incurred for the family to which it belongs. A mixed integer programming formulation for the problem is provided along with exact and heuristic solution methods. The exact algorithm uses cross decomposition. The proposed heuristic gives fast and tight bounds. In addition, a Benders decomposition algorithm is presented to solve the continuous relaxation of the problem. This method for solving the continuous relaxation can be used to improve the performance of …
Adapting Wright’S Modification Of Holt’S Method To Forecasting Intermittent Demand, Nezih Altay, Frank Rudisill, Lewis A. Litteral
Adapting Wright’S Modification Of Holt’S Method To Forecasting Intermittent Demand, Nezih Altay, Frank Rudisill, Lewis A. Litteral
Nezih Altay
The challenge of accurately forecasting demand for spare parts is due to the intermittent nature of their demand. This study compares a recent modification of Croston’s method and a method based on Holt’s double exponential smoothing taking the firm’s competitive priorities into consideration. Wright’s modification of Holt’s method is presented as a viable alternative when forecasting demand for spares especially when trend is present. Results indicate that firms focusing on minimizing inventory levels as a priority should consider forecasting using the Modified Croston’s method. If their priority is high customer service, then the modified Holt’s method is superior.