published_or_final_version / abstract / toc / Industrial and Manufacturing Systems Engineering / Master / Master of Philosophy

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The objective of the three essays of this doctoral dissertation is to investigate the strategic choices of organizational forms by competing firms in various environments. The first essay, which is a joint work with Professor Guofu Tan, provides an alternative theory of divestitures that relies on product-line complementarities and product market competition. We consider a simple environment in which there axe two firms, each supplying a group of complementary products and the products across groups axe imperfect substitutes. We model the firms' choices of divesting and pricing as a two-stage game. The duopohsts simultaneously choose their divestiture strategies in the first stage of the game and the independent divisions compete by setting prices in the second. It is shown that, when competing with each other, firms with complementary product-lines have incentives to split into multiple independent divisions supplying complementary products and services. Such divestitures increase prices and the parent firms' values but reduce aggregate social welfare. Moreover, the degree of divestiture, as we illustrate in the linear demand case, depends on the severity of competition and the nature of product-lines. Then, intensified competition due to deregulation, trade liberalization and entry may trigger divestitures. We further show that if two firms axe able to coordinate their divestiture strategies, they can achieve the joint monopoly prices and profits in a non-cooperative price game. The second essay analyzes the strategic incentive of oligopolists to create autonomous rival divisions when products are differentiated. We consider a two stage game where firms choose the number of autonomous divisions in the first stage and all the divisions engage in Cournot competition in the second. It is shown that product differentiation ensures the existence of an interior subgame perfect Nash equiubrium, and the equilibrium number of divisions increases with the degree of substitution among products and the number of firms. Further, if divisions are allowed to further divide, they always will, which leads to total rent dissipation. Thus, parent firms have incentives to unilaterally restrict their divisions from further dividing. In the free entry equihbrium, it is found that the possibility of setting up autonomous divisions is a natural barrier to entry. Incumbents may persistently earn abnormally high profits. In the cases where product differentiation is difficult, the only pure strategy free entry equilibrium is the monopoly outcome even if the entry cost is relatively low. The third essay develops a game theoretic model to analyze strategic leasing behaviors of landowners in a nonexclusively owned common oil pool. The oil field development is modeled as two more-or-less independent one-stage noncooperative game. The landowners choose leasing strategies in the first stage, and independent lease operators choose extraction strategies in the second. It is found that, in a nonexclusively owned oil field, it is individually rational for a landowner to unilaterally subdivide his landholding and delegate production rights to multiple independent firms, even though more dispersed production control leads to heavier common pool losses. Moreover, the degree of landownership concentration determines the degree of production concentration. The more fragmented the land ownership, the lower is the degree of production concentration i n equilibrium. The analysis offers an explanation for the puzzling landowners' leasing behaviors in U . S . onshore oil fields.

The three essays in this thesis address various problems in the general area of supply chain management. In general, supply chain management is concerned with management of the flow of goods, information, and funds among supply chain members, such as suppliers, manufacturers, distributors, retailers, and consumers. As such, its scope includes timing and quantity of material flow, logistics, improving efficiencies in problems with several decision makers, etc. The first essay in this thesis considers the problem of improving coordination in a decentralized system of retailers, while the second one addresses stability and profitability of Internet-based supply exchange alliances. The third essay analyzes a logistics problem, of finding an optimal route for a capacitated vehicle which travels on a graph and which can perform pickups and deliveries. In the first essay, we study a three-stage model of a decentralized distribution system with n retailers who each faces a stochastic demand for an identical product. In the first stage, before the demand is realized, each retailer independently orders her initial inventory. In the second stage, after the realization of the demand, each retailer decides what portion of her residual supply/demand she wants to share with the other retailers. In the third stage, residual inventories are transshipped in order to possibly meet residual demands, and an additional profit is allocated among the retailers. We study the effect of implementing various allocations rules in the third stage on the levels of the residual supply/demand the retailers are willing to share with others in the second stage, and the tradeoff involved in achieving a solution which is also optimal for the corresponding centralized system. The second essay is concerned with the formation of Internet-based supply exchange alliances among three or fewer retailers of possibly substitutable products. We provide some conditions, in terms of product substitutability and quality of suppliers, which would lead to the formation of a three member alliance, or a two member alliance, or no alliance at all. We also study the effect of alliance structure and quality of suppliers on the profit of a retailer. The third essay considers a vehicle routing problem with pickups and deliveries (VRPD problem) on some special graphs. Some vertices on the graph represent delivery customers, and other vertices represent pickup customers. The objective is to find a minimum length tour for a capacitated vehicle, which starts at a depot and travels on the graph while satisfying all the requests by the customers without violating the vehicle capacity constraint, and returns to a depot. We have developed linear time algorithms for the VRPD problem on a path and on tree graphs, linear and O (|V| log |V|) algorithm for a VRPD problem defined on a path with parametric initial capacity, and quadratic and O (|V|² log |V|) algorithms for a VRPD problem defined over a cycle graph.

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Thesis (M.B.A.)-Business Studies Unit, Durban Institute of Technology, 2005 x, 79 leaves / The study examines the supply chain management, within the business unit of EraBeier(Pty) Ltd. This business is situated in Pinetown South Africa. The concept of supply chain management is examined in terms of quality of material supplied, supplier evaluation, logistics, inventory and purchasing. These facets identified by the concept of supply chain management are prerequisites to achieving continuous process flow, are deemed crucial for effectiveness.