On April 20, 1995, Paul Allen Catlin passed away in Detroit, Michigan, at the age of 46, and the community of Graph Theory lost one of its best friends. Paul Catlin was born on June 25, 1948 in Bridgeport, Connecticut. His life-long love for mathematics was visible from the start. His younger brother, David Catlin, remembers Paul riding around on his tricycle counting for the sheer pleasure of ...

This memo presents current research in our laboratory. We address the following research topics: 1. Semantics-based assessment of nonmonotonic entailment methods for actions and change. 2. Implementation techniques for nonmonotonic entailment methods. 3. Algorithmic methods for planning and temporal reasoning. 4. Hybrid modelling of physical systems. 5. Design methodology for intelligent autono...

Auto-repeat is the automatic repetition of a function by continuous pressing of a button. In three separate tests, the design and operation of this auto-repeat feature for various electronical devices was examined. Eleven subjects took part in the experiment. Each subject was given the same stratgies for optimizing the auto-repeat feature. Both performance variables (ie. task completion time, n...

We examined the effect of prior victory or defeat in the same site as that of a subsequent encounter on the outcome of dyadic encounter of domestic hens by placing them in two situations: In the first set of dyads, two unacquainted hens having experienced prior victory were introduced in the site where one had experienced victory. In the second set, two unacquainted hens having experienced defe...

Acreative intellect, he contributed profoundly to our understanding of the molecular biology of development. From his early work on the structure of the eucaryotic chromosome to the recent identification of genes capable of etic-iting an entire program of cellular differentiation, Hal repeatedly identified important problems in biology and solved them in an elegant fashion. For those fortunate ...