Disertacija - Univerzitet u Novom Sadu

ABSTRACT
In an environment of continuing increase of cargo flows and reduced fossil fuel
resources, a strategic approach to supply chain management is becoming increasingly
important. The first step in a strategic approach to optimization of the supply chain is to
determine the optimal facility locations. Within this research two characteristic Supply
Chains were examined and modeling of the following location and allocation problems was
carried out:
1. public, international logistics centers with the distribution function and
2. solid biomass power plants.
The location allocation problem of public international logistics centers with the
distribution function is modeled as a single objective, discrete, static problem on the
network. The defined model considers locating one or more public logistics centers with
the distribution function on the existing transportation network as a set covering location
model for a defined gravitation area. The model determines the optimal number, type, size
and location of logistics centers, as well as the allocation of users to located centers,
based on the existing or expected cargo flows in the defined gravitational area, aiming
thereby to minimize the total supply chain costs. In comparison to previous researches, the
defined improved model enables selection of optimal logistic center type and optimal
transport mode for the macro flows of goods, considers impact of the share of certain
transport modes to the total cost of the supply chain, and when determining the optimal
capacity of the center, besides the value of investments, it considers also the fixed
operational cost of the center. To solve the location allocation problem with the help of
defined mathematical model, a genetic algorithm, which takes into consideration all the
aforementioned specificities, was developed. The model has been tested in the case study
of the Republic of Serbia. The results pointed out that transport costs of macro flows have
the biggest influence on the optimal number and location of centers, that share of transport
modes has a significant influence to the choice of optimal type, capacity and location of
centers, as well as that considering fixed operational costs of centers should be
considered when determining the optimal capacity. The testing, among others, concluded
that the formulated model represents a useful tool for making strategic decisions, not only
in the case of logistics centers’ location problem solving, but also in the design and
management of the distribution systems.
The location allocation problem of the solid biomass power plants is modeled as a
single objective, discrete, static problem on the network. The developed model, based on
the defined geographical region, available types of biomass and their spatial distribution,
yearly amount of biomass required, investments and operational costs of the plants, aims
to determine the optimal number, type, nominal power, location and allocation of the solid
biomass power plants for which the total cost per unit of generated electric power will be
the lowest. Additionally, the model should show the change of the total electrical energy
generation costs in relation to the change of the total installed capacity of all located power
plants, and on the basis of this change to define a limit of cost-effective total power to be
installed in the defined area. In comparison to previous researches, the defined improved
model enables selection of different types of solid biomass power plants, some of which
combining more biomass sorts. Also, two new coefficients enabling more precise mapping
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