The vlisp project has produced a rigorously veriied compiler from Scheme to byte codes, and a veriied interpreter for the resulting byte codes. The oocial denotational semantics for Scheme provides the main criterion of correctness. The Wand-Clinger technique was used to prove correctness of the primary compiler step. Then a state machine operational semantics is proved to be faithful to the de...

Objective: To examine a wide range of parentand teacher-reported behaviors in relation to child-reported depression and anxiety in preadolescence. Method: Subjects were participants in a longitudinal study of 420 preschool children from the general population that started in 1989. At second follow-up 8 years later (ages 10–11 years), usable parent information was obtained for 358 children. For ...

We havepreviously shown [1] that if theposition operator is definedas in ref. [21, themovementof the mean position ofa freeparticleobeys the classical equation u = P/P 0 where!’0 is the total energy, including the restmass. Conversely, it will be demonstrated here that the validity of this equation implies that, for spinless particles, the position operator is thatof ref. [2]. For spin 1/2 part...