This book is devoted to the mathematical theory of regularization methods and gives an account of the currently available results about regularization methods for linear and nonlinear ill-posed problems. Both continuous and iterative regularization methods are considered in detail with special emphasis on the development of parameter choice and stopping rules which lead to optimal convergence rates.

1 Industrial Mathematics in Linz The Johannes-Kepler-University is situated in Linz, which is the industrial center of Austria. This location provides unique opportunities for cooperation between in dustry and a university which derives its name from one of the most eminent ap plied mathematicians of all times. The mathematics department was founded in the late Sixties, the first students graduated in 1974. In these boom times, they had no problems of finding jobs in industry. However, their employers were then more interested in their general training than in their specific mathematical skills. To change this, the department decided to actively seek cooperation with industry in what we called "problem seminars," where students were trained to solve (under guidance) real-world problems from local industry. Groundwork was already laid by a curriculum with special emphasis on numerical analysis, statistics, and optim ization. This work in problem seminars usually evolved into diploma theses. Inci dentally, in all projects presented here, students were involved at some stages. While the original motivation for cooperation with industry was educational, it turned out that most problems presented to us also led to interesting mathematical problems, so that nowadays our motivation is as much scientific as educational. When cooperating with industry, one cannot expect that the problems to be solved fall into one's special mathematical interest.

This book is devoted to the mathematical theory of regularization methods and gives an account of the currently available results about regularization methods for linear and nonlinear ill-posed problems. Both continuous and iterative regularization methods are considered in detail with special emphasis on the development of parameter choice and stopping rules which lead to optimal convergence rates.

Dieses Lehrbuch behandelt zunachst den klassischen Stoff wie Riesz- und Fredholmtheorie in funktionalanalytischer Darstellung. Ein Schwerpunkt ist die Anwendung von Methoden und Ergebnissen aus der Theorie der Integralgleichungen auf gewoehnliche und partielle Differentialgleichungen. Neben der Behandlung der analytischen Aspekte wird auch auf die numerische Loesung von Integralgleichungen eingegangen. Spezifisch fur das Buch sind eine ausfuhrliche Behandlung von Integralgleichungen 1. Art, wie sie bei der Modellierung inverser Probleme auftreten, und ein Kapitel uber nichtlineare Integralgleichungen, das bis zu den Grundlagen der Verzweigungstheorie vordringt. Auch stark singulare Gleichungen werden behandelt. Das Lehrbuch wendet sich an Studenten, die die grundlegende Analysis-Ausbildung, inklusive der Grundlagen der linearen Funktionalanalysis, absolviert haben.