Ivana Lorenzová – Tomáš Štanzel, Jan (Johann) Böhm. Chemik(er) & fotograf

Petr Hájek , Tomáš Havránek

The Johann Jakob Wepfer Award 2010 of the European Stroke Conference to Professor Jan van Gijn.

The quantitative analysis of the Web of Science yielded 422 scientific publications attributed to Jan between 1969 and 2010. These articles have been cited in excess of 18,900 times. Many of the articles have been in journals with extremely high impact factors. The Web of Science classified the papers as covering an extraordinarily wide range of domains (the number in brackets that follows each...

Regular Böhm trees

Böhm trees are the natural infinite generalisations of normal forms in pure λ-calculus. They arose from the work of Böhm on separability (Böhm 1968), and were first identified by Barendregt, who devotes chapter 10 of his book (Barendregt 1980) to their study, and relates denotational models such as D∞ to appropriate quotients over Böhm trees. There is however no generally agreed presentation of...

Johann Wolfgang

Computing with Böhm Trees

This paper develops a general technique to analyze the head reduction of a term in a context. This technique is used to give a direct proof of the theorem of Hyland and Wadsworth : two -terms that have the same Böhm trees, up to (possibly infinite) -equivalence, are operationally equivalent. It is also used to prove a conjecture of R. Kerth : Every unsolvable -term has a decoration. This syntac...