Asia-Pacific Journal of Operational Research

This paper presents a stylized model to determine the optimal strategy for the integrated supplier-retailer inventory model under the condition that both the supplier and retailer have adopted a trade credit strategy. By analyzing the total channel profit function, we develop an algorithm to simultaneously determine the retailer's optimal order quantity and the number of shipment per production run from the supplier to the retailer. Our results demonstrate that the trade credit strategy is effective to supply chain system performance when customers are sensitive to the credit period length offered by the retailer. Moreover, when customers are sensitive to the credit period, if the retailer conveys partial advantage gained from the trade credit offered by the supplier to customers by suitably adjusting the customer's credit period then the entire system and every channel partner can benefit.

Multiple Attribute Decision Making (MADM) problem is a management science technique, which is popularly used to rank the priority of alternatives with respect to their competing attributes. It is popularly used in diverse fields such as engineering management, portfolio selection, transportation planning, and performance evaluation. Weights form the core of MADM: it is obvious that different weights lead to various evaluation results and decisions. Several approaches have been developed for assessing the weights of MADM problems, e.g., the eigenvector method, ELECTRE, and TOPSIS. However, an assessment approach of weights in MADM, which meets both the need of simplicity interface for practitioners and concrete theory for scholars is not easy, and balancing these two aspects is a challenging and tough task. Since the pay-off matrix in game theory could be regarded as a simple interface for data input/output, and very few scholars had ever explored the two-person zero-sum game on MADM problems. In this paper, the weights of a MADM problem are obtained by formulating it as a two-person zero-sum game with multiple decision makers. The group equilibrium solution, i.e., consensus of weights and the resolution steps for such a group MADM game has also been originally developed and validated in this study. Finally, an actual case of selecting the appropriate portfolio decision for a paper company is illustrated.

This paper deals with a problem of selecting profitable orders to accept out of sequentially arriving customers in a custom production company where only one customer is allowed to be held. It is assumed that a cost must be paid to search for orders, that a delay cost would be paid for every order not completed up to its due date, and that when there was no order in the system, the company could engage in sidelines yielding income. The purpose of this paper is twofold: One is to demonstrate that both admission control and pricing control problems for our customer selection problem can be analyzed within an identical framework and the other is to clarify the properties of the optimal decision rules for this particular problem.

An efficient mobility management for mobile stations plays an important role in mobile communication networks. Two basic operations of mobility management are location registration and paging. A zone-based registration (ZBR) is implemented in most of the mobile communication networks and we consider the mobility management scheme that combines a zone-based registration and a selective paging (SP). We propose a new analytical model that can reflect the characteristics of the ZBR smoothly where location areas of the ZBR are set up so that regions such as roads, bridges, rivers and mountains, where there is relatively little traffic, will constitute their boundaries. We adopt a revised 2-dimensional random walk mobility model to consider such characteristics. In addition, we propose a more efficient division scheme of location area for 2-step selective paging. We evaluate the performance of the mobility management scheme using our mobility model to determine the optimal size of a location area that will result in the minimum signaling traffic on radio channels. Numerical results are provided to demonstrate that our mobility model is useful to evaluate the ZBR more exactly. The results of this study can be used effectively in analyzing and comparing the performances of various mobility management schemes.

This theoretical paper presents a new construction algorithm for sparse 1-fault tolerant minimal broadcast networks (1-FTMBNs). To construct a large 1-FTMBN with the algorithm, identical nodes in copies of a broadcast network that is not fault tolerant are connected according to the edge structures of two known 1-FTMBNs with a special property. In most cases, computational results with this algorithm produce the best-known bounds on the cardinalities of the edge sets of the sparsest 1-FTMBNs with an odd number of nodes.

In packing steel products of coils into cassettes, we need to consider both the width and weight capacity of cassettes. Each coil has weight in (0, 1/3] and width in (1/6, 1/3] when scaling both the weight and width capacities to 1. With the objective of minimizing the number of cassettes to pack the coils, the problem is modeled by two-dimensional vector packing. To efficiently pack the coils having sizes specified by the ranges, we develop a 4/3-approximation algorithm.

An inverse optimization problem is defined as follows. Let S denote the set of feasible solutions of an optimization problem P, let c be a specified cost (capacity) vector, and x⁰ ∈ S. We want to perturb the cost (capacity) vector c to d so that x⁰ is an optimal solution of P with respect to the cost (capacity) vector d, and to minimize some objective function. In this paper, we consider the weighted inverse minimum cut problem under the bottleneck type Hamming distance. For the general case, we present a combinatorial algorithm that runs in strongly polynomial time.

In this paper, we establish a strong duality theorem for a pair of Mond–Weir type second-order nondifferentiable symmetric dual problems. This removes certain inconsistencies in some of the earlier results.