\chapter{Glossary and Definitions}

Definitions of some of the key terms appearing in this thesis.

\begin{itemize}

\item {\bf Fitness Function}: A fitness function is a mathematical
equation that describes the relative value of each member of a family
of objects with respect to some criterion. The fitness function is
maximized or minimized (depending upon the criterion) to find the best 
object in the family. For example, one could determine which set of
operating characteristics maximized the (revenue -- operating
expenses) criterion.

\item {\bf Landscape Analysis}: Landscape analysis is a mathematical
process used to search for the best solution to a multi-variable
optimization problem. It utilized a fitness function. Within the
search space (i.e., a plot of all the possible solutions), the fitness 
of a particular solution can be shown graphically as its height. The
resulting ``landscape'' will have peaks in the regions of the search
space that contain better solutions; further analysis of the peak
regions can be used to refine the results and achieve even more
precise solutions.

\item {\bf Multi-Objective Optimization}: Multi-objective optimization 
is the task of maximizing or minimizing a number of criteria
simultaneously. Multi-objective optimization is more difficult than
most kinds of optimization problems because the trade-offs between the 
multiple objectives may be unknown.

\item {\bf Simulated Annealing}: A mathematical technique for general
optimization problems. The same comes from the physical process of
annealing, during which a material is first heated and then slowly
cooled. During annealing, the component atoms of a material are
allowed to settle into a lower energy state so that a more stable
arrangement of atoms is maintained throughout the cooling process. SA
has been applied with success to a wide variety of optimization tasks.

\item {\bf Spin Glass}: Spin glasses are simplified models from
physics describing dilute magnetic alloys. They define an energy
function (or equivalently a fitness function) over tiny magnetic
dipoles called spins. Spins may point either up (+1) or down (-1). For 
every configuration of spins (e.g., +1-1+1+1-1 for a configuration of
5 spins), the energy function assigns that configuration's energy by
summing up the interactions between spins. many aspects of spin
glasses are utilized by physicists and they comprise a well-understood 
family of fitness landscapes.


etc. etc.




