| Title Page | 4 |
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| Copyright Page | 5 |
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| Table of Contents | 6 |
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| The XIXth International Workshop on Operator Theory and its Applications. II | 8 |
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| Exact Solutions to the Nonlinear Schrodinger Equation | 11 |
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| 1. Introduction | 11 |
| 2. Main results | 14 |
| 3. Examples | 18 |
| References | 21 |
| Robust Control, Multidimensional Systems and Multivariable Nevanlinna-Pick Interpolation | 23 |
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| 1. Introduction | 23 |
| 2. The 1-D systems/single-variable case | 28 |
| 2.1. The model-matching problem | 30 |
| 2.2. The frequency-domain stabilization and H8 problem | 30 |
| 2.3. The state-space approach | 32 |
| 2.4. Notes | 35 |
| 3. The fractional representation approach to stabilizability and performance | 35 |
| 3.1. Parametrization of stabilizing controllers in terms of a given stabilizing controller | 37 |
| 3.2. The Youla-Kucera parametrization | 41 |
| 3.3. The standard H8-problem reduced to model matching. | 45 |
| 3.4. Notes | 47 |
| 4. Feedback control for linear time-invariant multidimensional systems | 48 |
| 4.1. Multivariable frequency-domain formulation | 48 |
| 4.2. Multidimensional state-space formulation | 51 |
| 4.3. Equivalence of frequency-domain and state-space formulations | 62 |
| 5. Robust control with structured uncertainty: the commutative case | 68 |
| 5.1. Gain-scheduling in state-space coordinates | 69 |
| 5.2. Gain-scheduling: a pure frequency-domain formulation | 71 |
| 5.3. Robust control with a hybrid frequency-domain/state-space formulation | 71 |
| 5.4. Notes | 73 |
| 6. Robust control with dynamic time-varying structured uncertainty | 74 |
| 6.1. The state-space LFT-model formulation | 74 |
| 6.2. A noncommutative frequency-domain formulation | 79 |
| 6.3. Equivalence of state-space noncommutative LFT-model and noncommutative frequency-domain formulation | 84 |
| 6.4. Notes | 88 |
| References | 90 |
| Absence of Existence and Uniqueness for Forward-backward Parabolic Equations on a Half-line | 99 |
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| 1. Introduction | 99 |
| 2. Preliminaries | 101 |
| 3. Absence of existence and uniqueness | 102 |
| 4. Satisfaction of (C1)–(C4) | 105 |
| References | 107 |
| Bounds for Eigenvalues of the p-Laplacian with Weight Function of Bounded Variation | 109 |
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| 1. Introduction | 109 |
| 2. Generalized total variation | 111 |
| 3. Estimates of eigenvalues | 113 |
| 4. Optimality of bounds I | 116 |
| 5. Optimality of bounds II | 117 |
| 6. The periodic p-Laplacian | 120 |
| References | 122 |
| The Gelfand-Levitan Theory for Strings | 124 |
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| 1. Introduction | 124 |
| 2. Notation | 127 |
| 3. The spectral function .0,ß | 128 |
| 4. The transformation operator | 131 |
| 5. Existence of the transformation operator | 134 |
| 6. Smoothness | 139 |
| 7. The inverse problem | 139 |
| 8. The limit-point case | 141 |
| 9. The string | 142 |
| References | 144 |
| On the Uniqueness of a Solution to Anisotropic Maxwell’s Equations | 146 |
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| Introduction | 146 |
| 1. Basic boundary value problems for Maxwell’s equations | 147 |
| 2. A fundamental solution to Maxwell’s operator | 153 |
| 3. Green’s formulae | 160 |
| 4. Representation of solutions and layer potentials | 162 |
| 5. The uniqueness of a solution | 165 |
| References | 172 |
| Dichotomy and Boundedness of Solutions for Some Discrete Cauchy Problems | 174 |
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| 1. Introduction | 174 |
| 2. Preliminary results | 175 |
| 3. Dichotomy and boundedness | 177 |
| 4. The case of operators acting on Banach spaces | 180 |
| References | 182 |
| Control Laws for Discrete Linear Repetitive Processes with Smoothed Previous Pass Dynamics | 184 |
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| 1. Introduction | 184 |
| 2. Preliminaries and the new model | 186 |
| 3. Stability analysis | 188 |
| 4. Stabilization | 191 |
| 5. Robustness | 193 |
| 6. Numerical example | 198 |
| 7. Conclusions and further work | 200 |
| References | 201 |
| Fourier Method for One-dimensional Schrodinger Operators with Singular Periodic Potentials | 203 |
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| 1. Introduction | 203 |
| 2. Preliminary results | 206 |
| 3. Fourier representation of the operators LPer± | 221 |
| 4. Fourier representation for the Hill–Schrodinger operator with Dirichlet boundary conditions | 224 |
| 5. Localization of spectra | 230 |
| 6. Conclusion | 239 |
| References | 241 |
| Additive Invariants on Quantum Channels and Regularized Minimum Entropy | 245 |
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| 1. Introduction | 245 |
| 2. Proof of Theorem 1.1 | 247 |
| 3. Examples | 248 |
| 4. Bi-quantum channels | 251 |
| References | 252 |
| A Functional Model, Eigenvalues, and Finite Singular Critical Points for Indefinite Sturm-Liouville Operators | 254 |
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| 1. Introduction | 254 |
| 2. The functional model for indefinite Sturm-Liouville operators with one turning point | 257 |
| 2.1. Preliminaries | the functional model of a symmetric operator257 |
| 2.2. The functional model for J-self-adjoint extensions of symmetric operators | 258 |
| 2.3. The Sturm-Liouville case | 263 |
| 3. Point and essential spectra of the model operator A and of indefinite Sturm-Liouville operators | 267 |
| 3.1. Point spectrum of the model operator | 267 |
| 3.2. Essential and discrete spectra of the model operator and of indefinite Sturm-Liouville operators | 277 |
| 3.3. Non-emptiness of resolvent set for Sturm-Liouville operators | 279 |
| 4. The absence of embedded eigenvalues and other applications | 280 |
| 4.1. The absence of embedded eigenvalues for the case of infinite-zone potentials | 280 |
| 4.2. Other applications | 283 |
| 5. Remarks on indefinite Sturm-Liouville operators with the singular critical point 0 | 284 |
| 6. Discussion | 286 |
| Appendix A. Boundary triplets for symmetric operators | 289 |
| References | 290
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