This volume contains the papers which were presented to the workshop "Computer-Science Logic" held in Karlsruhe on October 12-16, 1987. Traditionally Logic, or more specifically, Mathematical Logic splits into several subareas: Set Theory, Proof Theory, Recursion Theory, and Model Theory. In addition there is what sometimes is called Philosophical Logic which deals with topics like nonclassical logics and which for historical reasons has been developed mainly at philosphical departments rather than at mathematics institutions. Today Computer Science challenges Logic in a new way. The theoretical analysis of problems in Computer Science for intrinsic reasons has pointed back to Logic. A broad class of questions became visible which is of a basically logical nature. These questions are often related to some of the traditional disciplines of Logic but normally without being covered adequately by any of them. The novel and unifying aspect of this new branch of Logic is the algorithmic point of view which is based on experiences people had with computers. The aim of the "Computer-Science Logic" workshop and of this volume is to represent the richness of research activities in this field in the German-speaking countries and to point to their underlying general logical principles.

This volume contains the papers which were presented at the second workshop "Computer Science Logic" held in Duisburg, FRG, October 3-7, 1988. These proceedings cover a wide range of topics both from theoretical and applied areas of computer science. More specifically, the papers deal with problems arising at the border of logic and computer science: e.g. in complexity, data base theory, logic programming, artificial intelligence, and concurrency. The volume should be of interest to all logicians and computer scientists working in the above fields.

This is the sixth in a series of conference proceedings of international conferences on computer algebra held in Europe. All the preceding ones have also been published as Lecture Notes in Computer Science. They contain original research material not published elsewhere, and a few invited lectures summarising the state of the art. Computer algebra is the science of using computers to do algebraic calculations, rather than the purely arithmetic calculations which we all know computers can do. These calculations may be polynomial-like calculations - one thread of the conference was devoted to polynomial algorithms - or may relate to other areas of mathematics such as integration, the solution of differential equations, or geometry - a second thread was devoted to those topics. The calculations can be applied in a wide range of scientific and engineering subjects, and in branches of mathematics. Physics has benefitted especially from these calculations, and the proceedings contain many papers on this, and also papers on applications in computer aided design and robotics, to name but a few other applications. The third thread of the proceedings was devoted to these applications and to the computer algebra systems which perform these calculations.