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EATCS Bulletin, Number 84, October 2004, Viii+258 Pp 1 1 ISSN 0252–9742 Bulletin of the European Association for Theoretical Computer Science EATCS E A T C S Number 84 October 2004 1 1 2 2 2 2 3 3 C E A T C S B: P:M N D V P:J L T N P S G T:D J B S:B R S B E:V S U K O C M: P D I J K¨ F M. D-C I D P I J D´ S Jˇ´ S C R Z´ É H A T P J E G W T G H G USA D W G A G UK E W S K I J G W¨ T N J-P J F U Z I EATCS M TCS: M E:W B G G R T N A S F TCS E:G A I M M USA D S U K P P: M N (1972–1977)M P (1977–1979) A S (1979–1985)G R (1985–1994) W B (1994–1997)J D´ (1997–2002) 3 3 4 4 EATCS C M Giorgio Ausiello . [email protected] Wilfried Brauer . [email protected] Pierpaolo Degano . [email protected] Mariangiola Dezani-Ciancaglini . [email protected] Josep Díaz . [email protected] Zoltán Ésik . [email protected] Javier Esparza . [email protected] Hal Gabow . [email protected] Alan Gibbons . [email protected] Kazuo Iwama . [email protected] Dirk Janssens . [email protected] Jean-Pierre Jouannaud . [email protected] Juhani Karhumäki . [email protected] Jan van Leeuwen . [email protected] Michael Mislove . [email protected] Mogens Nielsen . [email protected] David Peleg . [email protected] Jiríˇ Sgall . [email protected] Branislav Rovan . [email protected] Grzegorz Rozenberg . [email protected] Arto Salomaa . [email protected] Don Sannella . [email protected] Vladimiro Sassone . [email protected] Paul Spirakis . [email protected] Andrzej Tarlecki . [email protected] Wolfgang Thomas . [email protected] Dorothea Wagner . [email protected] Emo Welzl . [email protected] Gerhard Wöeginger . [email protected] Uri Zwick . [email protected] 4 4 5 5 Bulletin Editor: Vladimiro Sassone, Sussex, BN1 9QH, United Kingdom Cartoons: DADARA, Amsterdam, The Netherlands The bulletin is entirely typeset by TEX and CTEX in TX. The Ed- itor is grateful to Uffe H. Engberg, Hans Hagen, Marloes van der Nat, and Grzegorz Rozenberg for their support. All contributions are to be sent electronically to [email protected] and must be prepared in LATEX 2ε using the class beatcs.cls (a version of the standard LATEX 2ε article class). All sources, including figures, and a reference PDF version must be bundled in a ZIP file. Pictures are accepted in EPS, JPG, PNG, TIFF, MOV or, preferably, in PDF. Photographic reports from conferences must be arranged in ZIP files layed out according to the format described at the Bulletin’s web site. Please, consult http://www.eatcs.org/bulletin/howToSubmit.html. We regret we are unfortunately not able to accept submissions in other for- mats, or indeed submission not strictly adhering to the page and font layout set out in beatcs.cls. We shall also not be able to include contributions not typeset at camera-ready quality. The details can be found at http://www.eatcs.org/bulletin, including class files, their documentation, and guidelines to deal with things such as pictures and overfull boxes. When in doubt, email [email protected]. Deadlines for submissions of reports are January, May and September 15th, respectively for the February, June and October issues. Editorial decisions about submitted technical contributions will normally be made in 6/8 weeks. Accepted papers will appear in print as soon as possible thereafter. The Editor welcomes proposals for surveys, tutorials, and thematic issues of the Bulletin dedicated to currently hot topics, as well as suggestions for new regular sections. The EATCS home page is http://www.eatcs.org 5 5 6 6 6 6 7 7 Table of Contents 1 EATCS MATTERS . 1.1 L P ............................ 1.2 L E ............................... 1.3 R EATCS G A .............. 1.4 T EATCS A 2004 . 1.5 M,T S P, by A. Salomaa ......... 1.6 EATCS A 2005 . 1.7 F C .................................. 1.7.1 T J C ............................. 2 INSTITUTIONAL SPONSORS . 2.1 BRICS – B R C S ........... 2.2 IPA – I P R A 3 EATCS NEWS . 3.1 N A, by C.J. Fidge .................... 3.2 N I, by M. Mukund ....................... 3.3 N I, by A.K. Seda ...................... 3.4 N L A, by A. Viola .................. 3.5 N N Z, by C.S. Calude ............... 4 THE EATCS COLUMNS . 4.1 T A C, by J. D´ıaz .................. 4.2 T C C, by J. Torán ................... 4.3 T C C, by L. Aceto ................ 4.4 T F L T C, by A. Salomaa .... 4.5 T L C S C, by Y. Gurevich .. 5 TECHNICAL CONTRIBUTIONS . 5.1 S P R T C B G, by S.U. Khan and I. Ahmad .............. 5.2 P P, by C. Calude, E. Calude and S. Marcus . 5.3 M , R- , by V. Piirainen .................... 5.4 I L-O I D’ A, by M. Stay ..................... i 7 7 8 8 6 THE PUZZLE CORNER, by L. Rosaz ................... 7 MISCELLANEOUS . 8 REPORTS FROM CONFERENCES . 8.1 ICALP 2004 . 8.2 ACSD 2004 . 8.3 CCA 2004 . 8.4 CIAA 2004 . 8.5 FL 2004 . 8.6 GS 2004 . 8.7 SOS 2004 . 8.8 VODCA 2004 . 8.9 WACAM 2004 . 8.10 WMC5 . 9 ABSTRACTS OF PHD THESES . 10 EATCS LEAFLET . ii 8 8 9 9 EATCS M E A T C S 9 9 10 10 10 10 11 11 Letter from the President Dear EATCS members, As many of you will know, we had a very successful 31st ICALP in Turku this year, co-located with the annual IEEE Symposium on Logic in Computer Science, LICS’04. We are grateful to Juhani Karhumäki and all his colleagues in Turku for an excellent organization, and also to Phokion Kolaitis and our colleagues from the LICS community for making the event so special. On top of the two conferences, we had a number of interesting additional events, including a number of workshops, the Gödel prize ceremony, and the presentation of the 2004 EATCS Award . You will find many more details in this Bulletin. As usual we also had the annual EATCS General Assembly during ICALP, and you will find a report from this in this Bulletin. As you will see in the report, the number of EATCS members has increased during the past year, following a decrease in recent years. I hope that all our members will continue to encourage new young researchers in theoretical computer science to join our organization. Also you will see a number of new EATCS initiatives mentioned, including an EATCS Grand Challenge Initiative, based on a series of workshops aimed at identifying the major long term research challenges for our field. It is planned that this initiative will be launched at a workshop during ICALP’05. 3 11 11 12 12 BEATCS no 84 EATCS MATTERS The planning of ICALP’05 in Lisbon is running very well. I hope that we will see again a record number of submissions and workshop proposals. Please look out for the call for papers. At the General Assembly in Turku, Venice was unanimously chosen as the venue for ICALP’06, to be organised on the Island of San Servolo by Michele Bugliesi, University of Venice Ca’ Foscari. Also, it was decide to continue in 2006 with the new format of ICALP to be introduced in 2005. If you have any views on this or other EATCS matters, please let us know. Mogens Nielsen, Aarhus September 2004 4 12 12 13 13 Letter from the Bulletin Editor Dear Reader, Welcome to the October 2004 installment of the Bulletin of the EATCS. Coming just after major conferences, prizes and awards, October issues are usually very rich, and this one is no exception. ICALP 2004 in Turku was a great success. Besides the usual ‘best paper’ awards, it assigned the “Gödel Prize” for outstanding papers in theoretical computer science to Maurice Herlily, Nir Shanit, Michael Saks and Fotios Zaharoglou, for their landmark papers on distributed computation, and the “EATCS Award” for distinguished achievements to our own Arto Salomaa. The award ceremony was completed by two wonderful talks, which you’ll be able to read about in the Bulletin. Arto’s talk a witty recollection of over 40 years of scientific ‘encounters’ is recorded in this issue in the paper “Myhill, Turku and Sauna Poetry,” and a paper is in preparation by Maurice Herlily and Nir Shavit on the result that won them the Gödel Prize. It will appear in the next issue of our regular “Distributed Computing Column.” We recently endured three very sad losses: Shimon Even, Harald Ganzinger, and Larry Stockmeyer. I hope to publish papers in the coming issues to celebrate the lives and activities of such remarkable, distinguished members of our community. This issue marks my first year as the Bulletin Editor. I notice with satisfaction things getting easier, doubtless because of the efforts of column editors, regular and occasional contributors, and authors altogether, all of whom I thank heartily. Enjoy Vladimiro Sassone, Sussex September 2004 5 13 13 14 14 ICALP 2004 R EATCS G A 2004 The 2004 General Assembly of EATCS took place on Tuesday, July 13th, 2004, at the Mauno Koivisto Centre in Turku, the site of the ICALP.
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