The emergence of new paradigms for data management raises a variety of exciting challenges. An important goal of database theory is to answer these challenges by providing sound foundations for the development of the field. This volume contains the papers selected for the third International Conference on Database Theory, ICDT'90. The conferences in this series are held biannually in beautiful European cities, Rome in 1986 and Bruges in 1988 with proceedings published as volumes 234 and 326 in the same series. ICDT'90 was organized in Paris by the Institut National de Recherche en Informatique et Automatique. The conference features 2 invited presentations and 31 papers selected from 129 submissions. The papers describe original ideas and new results on the foundations of databases, knowledge bases, object-oriented databases, relational theory, transaction management, data structures and deductive databases. The volume offers a good overview of the state of the art and the current trends in database theory. It should be a valuable source of information for researchers interested in the field.

One out of every two men over eigthy suffers from carcinoma of the prostate.It is discovered incidentally in many patients with an alleged benign prostatic hyperplasia. In treating patients, the authors make clear that primary radical prostatectomy is preferred over transurethral resection due to the lower complication rate.

Neuere Entwicklungen im Datenbank- und Informationssystembereich sind u.a. gekennzeichnet durch die Bereitstellung sehr m{chtiger semantischer bzw. objektorientierter Datenmodelle, um den Anforderungen aus sogenannten Nicht-Standardanwendungen wie z.B. dem B}robereich gerecht zu werden. Daraus ergeben sich unmittelbar neue Problemstellungen imHinblick auf die Entwurfs- und Modellierungsaufgaben, die mit dem Einsatz derartiger m{chtiger Datenmodelle verbunden sind. Betrachtet manandererseits Entwicklungstendenzen im Bereich der K}nstlichen Intelligenz, so wird Fragen der systematischen Entwicklung Wissensbasierter Systeme eine immer gr|~ere Wichtigkeit beigemessen. Dabei spielen u.a. Phasen-Systeme und damit verbunden der Aufbau geeigneter Modelle eine zentrale Rolle. Dementsprechend hat der 2. Workshop "Informationssysteme und K}nstliche Intelligenz" gerade das Gebiet der Modellierung als generelles Thema. Zielsetzung ist dabei, auf dem Gebiet derModellierung Gemeinsamkeiten und Unterschiede von Problemstellungen bzw. L|sungsans{tzen, die in den Fachdisziplinen K}nstliche Intelligenz und Informationssysteme/Datenbanksysteme identifiziert bzw. entwickelt worden sind, herauszuarbeiten. Damit soll gleichzeitig der Gedankenaustausch zwischen den beteiligten Fachdisziplinen gef|rdertund die Zusammenarbeit }ber Fachdisziplinen hinweg verbessert werden.

The main idea behind the series of volumes Advances in Petri Nets is to present to the general computer science community recent results which are the most representative and significant for the development of the area. The papers for the volumes are drawn mainly from the annual International Conferences on Applications and Theory of Petri Nets. Selected papers from the latest conference are independently refereed, and revised and extended as necessary. Some further papers submitted directly to the editor are included. Advances in Petri Nets 1990 covers the Tenth International Conference on Applications and Theory of Petri Nets held in Bonn, Germany, in June 1989. Additional highlights of this volume include a tutorial on refinements of Petri nets by W. Brauer, R. Gold, and W. Vogler, and a tutorial on analysis and synthesis of free choice systems by J. Esparza and M. Silva, both prepared in the framework of the ESPRIT Basic Research Actions Project DEMON.

This volume is the product of the Proceedings of the 9th International Congress of Logic, Methodology and Philosophy of Science and contains the text of most of the invited lectures. Divided into 15 sections, the book covers a wide range of different issues. The reader is given the opportunity to learn about the latest thinking in relevant areas other than those in which they themselves may normally specialise.

This volume contains the proceedings of the second workshop on Computer Aided Verification, held at DIMACS, Rutgers University, June 18-21, 1990. Itfeatures theoretical results that lead to new or more powerful verification methods. Among these are advances in the use of binary decision diagrams, dense time, reductions based upon partial order representations and proof-checking in controller verification. The motivation for holding a workshop on computer aided verification was to bring together work on effective algorithms or methodologies for formal verification - as distinguished, say,from attributes of logics or formal languages. The considerable interest generated by the first workshop, held in Grenoble, June 1989 (see LNCS 407), prompted this second meeting. The general focus of this volume is on the problem of making formal verification feasible for various models of computation. Specific emphasis is on models associated with distributed programs, protocols, and digital circuits. The general test of algorithm feasibility is to embed it into a verification tool, and exercise that tool on realistic examples: the workshop included sessionsfor the demonstration of new verification tools.

The workshop Computer Science Logic '90 was held at the Max-Planck-Haus in Heidelberg, Germany, October 1-5, 1990. It was the fourth in a series of worskhops, following CSL '89 at the University of Kaiserslautern (see LNCS 440), CSL '88 at the University of Duisberg (see LNCS 385), and CSL '87 at the University of Karlsruhe (see LNCS 329). This volume contains 24 papers, chosen by means of a review procedure from the 35 papers presented at the workshop, some of which were invited and some selected from a total of 89 submissions. The papers cover a wide range of topics arising from the applications of logic to computer science.

This volume contains papers selected from the contributions to the 4th International Workshop on Graph Grammars and Their Application to Computer Science. It is intended to provide a rich source of information on the stateof the art and newest trends to researchers active in the area and for scientists who would like to know more about graph grammars. The topics of the papers range from foundations through algorithmic and implemental aspects to various issues that arise in application areas like concurrent computing, functional and logic programming, software engineering, computer graphics, artificial intelligence and biology. The contributing authors are F.-J. Brandenburg, H. Bunke, T.C. Chen, M. Chytil, B. Courcelle, J. Engelfriet, H. G|ttler, A. Habel, D. Janssens, C. Lautemann, B. Mayoh, U. Montanari, M. Nagl, F. Parisi-Presicci, A. Paz, P. Prusinkiewics, M.R. Sleep, A. Rosenfeld, J. Winkowski and others.

The innovative progress in the development of parallel computing systems and their increasing availability have caused a rise in interest in the scientific principles that underlie parallel computation and parallel programming. The biannual Parallel Architectures and Languages Europe (PARLE) conferences aim to present current research on all aspects of the theory, design and application of parallel computing systems and parallel processing.