The present book is the first of the two volume Proceedings of the Mark Krein International Conference on Operator Theory and Applications. This conference, which was dedicated to the 90th Anniversary of the prominent mathematician Mark Krein, was held in Odessa, Ukraine from 18-22 August, 1997. The confer encefocused onthemain ideas, methods, results, andachievementsofM.G. Krein. This first volume is devoted to the theory of differential operators and related topics. It opens with a description of the conference, biographical material and a number of survey papers about the work of M.G. Krein. The main part of the book consists oforiginal research papers presenting the stateofthe art in the area ofdifferential operators. The second volume of these proceedings, entitled Operator Theory and related Topics, concerns the other aspects of the conference. The two volumes will be of interest to a wide-range of readership in pure and applied mathematics, physics and engineering sciences. Table of Contents Preface............................................................. v Table of Contents VII Picture of M.G. Krein Xl About the Mark Krein International Conference . Mark Grigorevich Krein (A short biography) 5 I. Gohberg The Seminar on Ship Hydrodynamics, Organized by M.G. Krein 9 v.G. Sizov Review Papers: The Works ofM.G. Krein on Eigenfunction Expansion for Selfadjoint Operators and their Applications and Development 21 Yu.M. Berezansky M.G. Krein and the Extension Theory of Symmetric Operators.

Inhalt
About the Mark Krein International Conference.- Mark Grigorevich Krein (A short biography).- The Seminar on Ship Hydrodynamics, Organized by M.G. Krein.- Review Papers: The Works of M.G. Krein on Eigenfunction Expansion for Selfadjoint Operators and their Applications and Development.- M.G. Krein and the Extension Theory of Symmetric Operators. Theory of Entire Operators.- Works by M.G. Krein on Inverse Problems.- Research Papers: The Spectrum of Periodic Point Perturbations and the Krein Resolvent Formula.- The Periodic Choquard Equation.- On the Best Constant in a Poincare-Sobolev Inequality.- On Solutions of Parabolic Equations from Families of Banach Spaces Dependent on Time.- Canonical Systems on the Line with Rational Spectral Densities: Explicit Formulas.- Oscillations in Systems with Periodic Coefficients and Sector-restricted Nonlinearities.- Differential Operator Matrices of Mixed Order with Periodic Coefficients.- Asymptotics of Generalized Eigenvectors for Unbounded Jacobi Matrices with Power-like Weights, Pauli Matrices Commutation Relations and Cesaro Averaging.- Functional Means, Convolution Operators and Semigroups.- The Inverse Spectral Problem for First Order Systems on the Half Line.- Exact Solution of the Marchenko Equation Relevant to Inverse Scattering on the Line.- An Arbitrary Oriented Crack in the Box Shell.- Homogeneity of a String having Three Unperturbed Spectra.- On the Integro-differential Equation of a Torsion of an Elastic Medium Including a Cylindrical Crack.- Green's Formula and Theorems on Isomorphisms for General Elliptic Problems for Douglis-Nirenberg Elliptic Systems.- Sobolev's Problem in Complete Scale of Banach Spaces.- On the Simple Waves with Profiles in the Form of some Special Functions-Chebyshov-Hermite, Mathiev,Whittaker-in Two-phase Media.- Inverse Spectral Problem Related to the N-wave Equation.- Degenerated Hyperbolic Approximations of the Wave Theory of Elastic Plates.- Elliptic Problems with a Shift in Complete Scales of Sobolev-type Spaces.- On the Extremal Regularization of the Variational Inequalities with Multivalued Operators.- Poly-Fock Spaces.- Diffraction of Longitudinal Shear Waves by a Hollow Thick Circular Cylinder which is Situated in the Elastic Halfspace.- On M.G. Krein's Spectral Shift Function for Canonical Systems of Differential Equations.- Table of Contents of Volume II.