Bulletin of the EATCS, Volume 40

Volume 40, February 1990

Computational Geometry Column

The Algebraic Specification Column

Jacques Loeckx: The Specification System OBSCURE. 168-171
Hartmut Ehrig, Ingo Claßen: Overview of Algebraic Specification Languages Environments and Tools, and Algebraic Specifications of Software Systems. 172-181

The Structural Complexity Column

Eric Allender, Klaus W. Wagner: Counting Hierarchies: Polynomial Time and Constant. 182-194

The Formal Language Theory Column

Jarkko Kari: Games played on the plane: Solitaire and Cellular Automata. 195-200

Technical Contributions

Roland Carl Backhouse, Grant Malcolm: On induced congruences. 201-206
Jan Van den Bussche: A formal basis for extending SQL to object-oriented databases. 207-216
Christian Choffrut: An Optimal Algorithm for building the Boyer-Moore automaton. 217-224
Michael Formann, Gerhard J. Woeginger: On the reconstruction of simple polygons. 225-230
Martin Gogolla: A note on the translation of SQL tuple calculus. 231-235
Werner Loch: On the equivalence problem for DTOL systems. 236-246
Heiner Marxen, Jürgen Buntrock: Attacking the Busy Beaver 5. 247-251
Edward Ochmanski: Notes on a star mystery. 252-256
Gheorghe Paun: Non-centralized parallel communicating grammar systems. 257-264
Gabriele Ricci: Most definitions of trees over an alphabet are wrong. 265
Andrzej Szepietowski: A week mode of space complexity can be used in the proof that [DSPACE(log log n) = NSPACE(log logn)] => [L = NL]. 266-269
Paavo Turakainen: On the finitess of the multiplicable monoid generated by a nonnegative matrix. 270-272