This book is motivated largely by a desire to solve shape optimization
prob- lems that arise in applications, particularly in structural
mechanics and in the optimal control of distributed parameter systems.
Many such problems can be formulated as the minimization of functionals
defined over a class of admissible domains. Shape optimization is quite
indispensable in the design and construction of industrial structures.
For example, aircraft and spacecraft have to satisfy, at the same time,
very strict criteria on mechanical performance while weighing as little
as possible. The shape optimization problem for such a structure
consists in finding a geometry of the structure which minimizes a given
functional (e. g. such as the weight of the structure) and yet
simultaneously satisfies specific constraints (like thickness, strain
energy, or displacement bounds). The geometry of the structure can be
considered as a given domain in the three-dimensional Euclidean space.
The domain is an open, bounded set whose topology is given, e. g. it may
be simply or doubly connected. The boundary is smooth or piecewise
smooth, so boundary value problems that are defined in the domain and
associated with the classical partial differential equations of
mathematical physics are well posed. In general the cost functional
takes the form of an integral over the domain or its boundary where the
integrand depends smoothly on the solution of a boundary value problem.