The three volumes of the WDS Proceedings you just obtained are composed of the contributions which have been presented during the last 12th Annual Conference of Doctoral Students. This international conference was held traditionally in Prague, at Charles University, Faculty of Mathematics and Physics from June 10 to June 13, 2003. The contributions were divided into different symposia in accordance with their topics and consisted of both invited lectures of professors and shorter contributions, which were presented as oral contributions or posters by doctoral students. The number of presentations reached 170 in this year and 123 of them have been accepted for a publication in the Proceedings. It is seen from this short survey that the relationship between presentations and published papers is increasing. Proceedings are divided into three volumes. Part I presents the contributions on Mathematics and Computer Sciences (together 42 papers). The contributions from the field of Physics of Plasmas and Ionized Media are the main topics of Part II (42 papers have been submitted from this symposium). Part III consists of contributions from all other symposia on Physics (39 papers). All student's contributions in these volumes have been refereed by the supervisor. I would like to thank all the supervisors for their fruitful comments. However, each volume is further divided into two sections: Refereed and Non-refereed contributions. The papers in the refereed part have been usually refereed by two referees (no supervisor) and these papers have been accepted for publication after corresponding revisions. In this year, a number of these contributions reached 81. I would like to thank the referees from different institutions who worked so hard to review the student's papers, and thus permitted the timely production of these volumes: Part I: Z. Prášková, K. Zvára, J. Štěpán, S. Schwabík, D. Zeman, M. Kulich, P. Lachout, V. Janovský, P. Mayer, P. Knobloch, M. Feistauer, V. Dolejší, Z. Šír, O. John, P. Savický, J. Krajíček, J. Sgall, P. Štěpánek, F. Hakl, J. Ivánek, J. Flusser, J. Pelikán, P. Brada, M. Lopatková, Z. Žabokrtský, E. Hajičová, J. Panevová, P. Valtr, M. Klazar, J. Veselý, Part II: A. Kaňka, L. Přech, R. Plašil, O. Santolík, J. Kasper, L. Zajíčková, F. Krčma, G. N. Zastenker, H. Biedermann, J. Pavlík, M. Tichý, L. Krlín, P. Kudrna, Z. Hubička, Z. Sternovský, J. Richardson, I. Čermák, V. Hrachová, J. Šafránková, J. Glosík, R. Hrach, J. Měrka, Part III: V. Karas, M. Šolc, M. Wolf, J. Hořejší, P. Ambrož, F. Gemperle, P. Mayer, P. Chvosta, J. Langer, F. Honda, J. Dian, V. Šíma, P. Mojzeš, P. Čapková, K. Mašek, I. Bartoš, J. Oswald, P. Hlídek, P. Malý, P. Němec, L. Vecsey, L. Judas, K. Prokeš, A. Raidl, S. Novák, M. Vicher, A. Brablec, R. Hrach, D. Novotný, I. Ošťádal, L. Skrbek, H. Štěpánková. Zdroj anotace: OKCZ - ANOTACE Z WEBU