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.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:BVAU.2429/13611 |
| Date | 11 1900 |
| Creators | Sosic, Greys |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Relation | UBC Retrospective Theses Digitization Project [http://www.library.ubc.ca/archives/retro_theses/] |
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