COMMISSION 4 * ISSN 0014-2352 OF THE EUROPEAN COMMUNITIES EURO ABSTRACTS Scientific and technical publications from Community-funded research and development VOL. 28 N° 5/1990 ABSTRACTS : PUBLICATIONS 28/401-28/500 EURO ABSTRACTS is compiled by the Commission of the European Communities DGXIII 'Telecommunications, Information Industries and Innovation' and published by the Office for Official Publications of the European Communities in association with ECOTEC Research and Consulting Ltd EABS, the on-line version of Euroabstracts, is accessible free of charge through ECHO (European Commission Host Organization) For Information, please contact : ECHO Support ; 177, route d'Esch ; L-1471 LUXEMBOURG EURO ABSTRACTS The abstracting journal of scientific and technical publications of the Commission of the European Communities Vol. 28 May 1990, N° 5 BEZUGSQUELLEN COMMENT AVAILABILITY SE PROCURER LES DOCUMENTS Veröffentlichungen Publications Publications These comprise reports, papers and articles Diese umfassen Berichte, Vorträge und Artikel, Par publications, on entend les rapports, exposés die im Rahmen des wissenschaftlichtechniscovering the scientific and technical programme oraux et anieles issues du programme scientichen Programms der Europäischen Gemeinschafof the European Communities. The addresses fique et technique des Communautés européenwhere full texts may be ordered are indicated by ten erstellt wurden. Die Texte können bei fol nes.