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International Conference on Differential, Difference Equations and Their Differential, Difference Applications Differential, Difference Equations and Their Applications Their and Equations Difference Differential, on Conference International International Conference on International Conference on Differential, Difference Equations and Their Differential, Difference Applications 1–5 July 2002, Patras, Greece Equations and Their Edited By: Panayiotis D. Siafarikas Applications The International Conference on Differential, Difference Equations and 1–5 July 2002, Patras, Greece Their Applications (ICDDEA), dedicated to Professor Evangelos K. Ifantis, took place from 1 to 5 July 2002, at the Conference and Cultural Centre of the University of Patras, Patras, Greece. The aim of the conference was to provide a common meeting ground for specialists in differential equations, Edited By: Panayiotis D. Siafarikas difference equations, and related topics, as well as in the rich variety of scientific applications of these subjects. This conference intended to cover, and was a forum for presentation and discussion of, all aspects of differential equations, difference equations, and their applications in the scientific areas of mathematics, physics, and other sciences. In this conference, 101 scientists participated from 26 countries (Australia, Bulgaria, Canada, Chile, Czech Republic, Finland, France, Georgia, Great Britain, Greece, Hungary, Iran, Israel, Italy, Japan, Latvia, Mozambique, Netherlands, Norway, Poland, Romania, Singapore, Slovakia, Spain, Ukraine, and United States of America). The scientific program consisted of 4 plenary lectures, 37 invited lectures, and 42 research seminars. The contributions covered a wide range of subjects of differential equations, difference equations, and their applications. INDAWI Hindawi Publishing Corporation http://www.hindawi.com ICDDEA-POB.indd 1 11/29/2004 3:14:05 PM International Conference on Differential, Difference Equations and Their Applications 1–5 July 2002, Patras, Greece Edited By: Panayiotis D. Siafarikas Hindawi Publishing Corporation http://www.hindawi.com Copyright © 2004 Hindawi Publishing Corporation. All rights reserved. http://www.hindawi.com CONTENTS Preface................................................................... v Evangelos K. Ifantis and his work, Panayiotis D. Siafarikas ..................... 1 The mathematicians’ share in the general human condition, Nicolas K. Artemiadis ...................................................... 11 Positive solutions for singular discrete boundary value problems, Mariella Cecchi, Zuzana Doˇsla,´ and Mauro Marini ............................ 17 Symplectic difference systems: oscillation theory and hyperbolic Prufer¨ transformation, Ondˇrej Doˇsly´ ........................................ 31 Integral representation of the solutions to Heun’s biconfluent equation, S. Belmehdi and J.-P. Chehab ............................................... 41 On the exterior magnetic field and silent sources in magnetoencephalography, George Dassios and Fotini Kariotou .......................................... 53 New singular solutions of Protter’s problem for the 3D wave equation, M. K. Grammatikopoulos, N. I. Popivanov, and T. P. Popov...................... 61 Linear differential equations with unbounded delays and a forcing term, Jan Cermˇ ak´ and Petr Kundrat´ ............................................... 83 Comparison of differential representations for radially symmetric Stokes flow, George Dassios and Panayiotis Vafeas ........................................ 93 Zero-dispersion limit for integrable equations on the half-line with linearisable data, A. S. Fokas and S. Kamvissis .................................107 On sampling expansions of Kramer type, Anthippi Poulkou .................... 117 A density theorem for locally convex lattices, Dimitrie Kravvaritis and Gavriil Paltineanu˘ .................................. 133 On periodic-type solutions of systems of linear ordinary differential equations, I. Kiguradze...............................................................141 On the solutions of nonlinear initial-boundary value problems, Vladim´ır Durikoviˇ ˇc and Monika Durikoviˇ ˇcova´ ................................ 153 iv Contents On a nonlocal Cauchy problem for differential inclusions, E. Gatsori, S. K. Ntouyas, and Y. G. Sficas ..................................... 171 Exact solutions of the semi-infinite Toda lattice with applications to the inverse spectral problem, E. K. Ifantis and K. N. Vlachou ............................. 181 Nonanalytic solutions of the KdV equation, Peter Byers and A. Alexandrou Himonas ...................................... 199 Subdominant positive solutions of the discrete equation ∆u(k + n) =−p(k)u(k), Jarom´ır Baˇstinec and Josef Dibl´ık ............................................ 207 Electromagnetic fields in linear and nonlinear chiral media: a time-domain analysis, Ioannis G. Stratis and Athanasios N. Yannacopoulos....................217 Efficient criteria for the stabilization of planar linear systems by hybrid feedback controls, Elena Litsyn, Marina Myasnikova, Yurii Nepomnyashchikh, and Arcady Ponosov ................................. 233 Which solutions of the third problem for the Poisson equation are bounded? Dagmar Medkova´ ......................................................... 247 Darboux-Lame´ equation and isomonodromic deformation, Mayumi Ohmiya . 257 Multivalued semilinear neutral functional differential equations with nonconvex-valued right-hand side, M. Benchohra, E. Gatsori, and S. K. Ntouyas .................................. 271 Conditions for the oscillation of solutions of iterative equations, Wiesława Nowakowska and Jarosław Werbowski ............................... 289 On certain comparison theorems for half-linear dynamic equations on time scales, Pavel Rehˇ ak´ ................................................. 297 On linear singular functional-differential equations in one functional space, Andrei Shindiapin ................................................... 313 Nonmonotone impulse effects in second-order periodic boundary value problems, Irena Rachunkov˚ aandMilanTvrd´ y´ ...........................323 Nonuniqueness theorem for a singular Cauchy-Nicoletti problem, Josef Kalas ................................................................ 337 Accurate solution estimates for nonlinear nonautonomous vector difference equations, Rigoberto Medina and M. I. Gil’..........................349 Generalizations of the Bernoulli and Appell polynomials, Gabriella Bretti, Pierpaolo Natalini, and Paolo E. Ricci ......................... 359 APPENDICES Listoflectures............................................................ 371 ListofparticipantsoftheICDDEAconference............................... 375 PREFACE The International Conference on Differential, Difference Equations and Their Applica- tions (ICDDEA), dedicated to Professor Evangelos K. Ifantis, took place from 1 to 5 July, 2002, at the Conference and Cultural Centre of the University of Patras, Patras, Greece. The aim of the conference was to provide a common meeting ground for specialists in differential equations, difference equations, and related topics, as well as in the rich vari- ety of scientific applications of these subjects. This conference intended to cover, and was a forum for presentation and discussion of, all aspects of differential equations, difference equations, and their applications in the scientific areas of mathematics, physics, and other sciences. In this conference, 101 scientists participated from 26 countries (Australia, Bulgaria, Canada, Chile, Czech Republic, Finland, France, Georgia, Great Britain, Greece, Hun- gary, Iran, Israel, Italy, Japan, Latvia, Mozambique, Netherlands, Norway, Poland, Roma- nia, Singapore, Slovakia, Spain, Ukraine, and United States of America). The scientific program consisted of 4 plenary lectures, 37 invited lectures, and 42 research seminars. The contributions covered a wide range of subjects of differential equations, difference equations, and their applications. The social program of the conference consisted of a welcome dinner and a guided visit at the Residence of Achaia Clauss winemakers, a Greek evening with traditional Greek dances and dinner at the private restaurant of the hotel Rio Beach, a visit at the castle of the picturesque city Nafpaktos with lunch at a traditional Greek taverna at the village of Eratini, a guided visit to ancient Delphi with dinner at a private restaurant at Nafpaktos, and a farewell dinner at the private restaurant “Parc de la Paix,” near the conference cite. This volume contains the papers that were accepted for publication after an ordinary refereeing process and according to the standards of the journal “Abstract and Applied Analysis”; we thank the referees, who helped us to guarantee the quality of the papers, for their work. Also I would like to thank the International Scientific Committee (Ondrejˇ Doslˇ y,´ Takasi Kusano, Andrea Laforgia, and Martin Muldoon) for their support and co- operation concerning the refereeing process, as well as the other members of the Local Organizing Committee (Chrysoula Kokologiannaki and Eugenia Petropoulou) for their help. Finally, I would like to thank the editors and especially the Editor-in-Chief, Profes- sor Athanassios Kartsatos, of the journal “Abstract and Applied Analysis,” which hosted the Proceedings of the ICDDEA. vi Preface We would also like to thank the Research Committee of the University of Patras, the Hellenic Ministry of Education and Religious Affairs, the Academy of Athens, the Munic- ipality of Patras, the
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