International Journal of Industrial Engineering & Production Research

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  Response time is one of the critical web service quality dimensions. It refers to how long it takes that a web service responds to request of a user. In order to manage the response time, pricing schemes can work as an efficient access control mechanism. In this paper, we study competition between two providers offering functionally same web services where there is a monopoly service provider. The monopoly offers a service that is complementary to their services. Each provider needs to decide a service level (L or H) and a corresponding price for the selected service level to meet the service level guarantee. We construct a Stackelberg game and benefit from queuing theory concept to propose a model that can examine strategic choices of the providers .

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We model a real-world case problem as a price competition model between two leader-follower supply chains that each of them consists of one manufacturer and one retailer. T he manufacturer produces partially differentiated products and sells to market through his retailer. The retailer sells the products of manufacturer to market by adding some values to the product and gains margin as a fraction of the all income of selling products. We use a two-stage Stackelberg game model to investigate the dynamics between these supply chains and obtain the optimal prices of products. We explore the effect of varying the level of substitutability coefficient of two products on the profits of the leader and follower supply chains and derive some managerial implications. We find that the follower supply chain has an advantage when the products are highly substitutable. Also, we study the sensitivity analysis of the fraction of requested margin by retailer on the profit of supply chains.

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In this study, an optimization model is proposed to design a Global Supply Chain (GSC) for a medical device manufacturer under disruption in the presence of pre-existing competitors and price inelasticity of demand. Therefore, static competition between the distributors’ facilities to more efficiently gain a further share in market of Economic Cooperation Organization trade agreement (ECOTA) is considered. This competition condition is affected by disruption occurrence. The aim of the proposed model is to maximize the expected net after-tax profit of GSC under disruption and normal situation at the same time. To effectively deal with disruption, some practical strategies are adopted in the design of GSC network. The uncertainty of the business environment is modeled using the robust optimization technique based on the concept of uncertainty budget. To tackle the proposed Mixed-Integer Nonlinear Programming (MINLP) model, a hybrid Taguchi-based Memetic Algorithm (MA) with an adaptive population size is developed that incorporates a customized Adaptive Large Neighborhood Search (ALNS) as its local search heuristic. A fitness landscape analysis is used to improve the systematic procedure of neighborhood selection in the proposed ALNS. A numerical example and computational results illustrate the efficiency of the proposed model and algorithm in dealing with global disruptions under uncertainty and competition pressure.

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In today complex worldwide supply chains, intermediary organizations like Contract manufacturers and GPOs are mostly used. Well-known OEMs delegate their purchasing and procuring to these intermediaries. Because of their positive influence on supply chain efficiency, it is very important to investigate the role of intermediaries in today competitive supply chains. One important question arising about intermediaries is the conditions that the OEM controls his procurement or delegates this task to the intermediary organization?

To answer this question, this paper studies the equilibrium for component procurement strategies of two competing OEMs that produce substitutable products. Each OEM may either directly procure the input from the component supplier, or delegate the procurement task to the contract manufacturer. We analyze the OEMs’ procurement game under two contracting power schemes in such a supply chain: the supplier Stackelberg, where the component supplier acts as the Stackelberg leader, and the OEM Stackelberg, where the OEMs are the first movers.

We show that, the smaller OEM always prefers direct control of component procurement. This is because the OEM will receive a lower component price if the component supplier can price discriminate the OEMs. In contrast, the larger OEM’s preference depends on the contracting power scheme. Under the supplier Stackelberg, the larger OEM never prefers direct procurement; however, under the OEM Stackelberg, the larger OEM may have incentives to use direct procurement under reasonable conditions. This implies that a shift of the market power from the supplier to the OEMs may lead to more OEMs deviating from delegation to direct control.

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In this research, we analyze a supply chain involving two competing manufacturers that sells their product through two common competing retailers. The manufacturers’ products are the same but with different brand in market. The retailers face stochastic demand where demand is a decreasing function of price with additive uncertain part. Manufacturers compete on supplying orders where retailers compete on selling price. Each manufacturer set wholesale price contract with retailers similarly. We examine supply chain coordination with wholesale price contract under competition and demand uncertainty. The analytical results show that under coordination condition, manufacturers do not obtain any positive profit and consequently the retailers intend to increase wholesale prices. On the other hand, manufacturers can increase wholesale prices until the retailers’ profit becomes zero. Hence, with a numerical study for actual cases, it is found that changing demand sensitivity and competition intensity affect the optimal decisions of ordering and pricing. Moreover, increasing in competition sensitivity, increase the supply chains’ efficiency, stocking level and selling price. The concluding remarks show that further investigation is required for possibility of coordination under competition by other contractual mechanisms.