This paper investigates an approach to substitution alternative to the implicit treatment of the λ-calculus and the explicit treatment of explicit substitution calculi. In this approach, substitutions are delayed (but not executed) explicitly. We implement this idea with two calculi, one where substitution is a primitive construction of the calculus, the other where substitutions is represented...

Various calculi have been designed for qualitative constraintbased representation and reasoning. Especially for orientation calculi, it happens that the well-known method of algebraic closure cannot decide consistency of constraint networks, even when considering networks over base relations (= scenarios) only. We show that this is the case for all relative orientation calculi capable of distin...

The past decade has seen an explosion of work on calculi of explicit substitutions. Numerous work has illustrated the usefulness of these calculi for practical notions like the implementation of typed functional programming languages and higher order proof assistants. It has also been shown that eta-reduction is useful for adapting substitution calculi for practical problems like higher order u...

PURPOSE Renal calculi are a significant source of morbidity for patients with neurogenic bladder. Calculi from patients with NB have traditionally been composed primarily of struvite and carbonate apatite secondary to chronic urea-splitting bacteriuria. In the current era there have been great improvements in the urological rehabilitation of patients with NB. We defined the composition of renal...

Introduction: Our goal was to investigate the efficacy of flexible ureteroscopy (FU) in the treatment of pyelocaliceal calculi. Materials and Methods: Between September 2002 and December 2004, a total of 41 patients with multiple (23 cases), pelvic (7 cases), and inferior caliceal (11 cases) SWL-resistant calculi underwent FU. We used a 7.5-F flexible ureteroscope with pressure irrigation and e...

Explicit substitution calculi are extensions of the -calculus where the substitution mechanism is internalized into the theory. This feature makes them suitable for implementation and theoretical study of logic based tools as strongly typed programming languages and proof assistant systems. In this paper we explore new developments on two of the most successful styles of explicit substitution c...

Gutkovas, R. 2016. Languages, Logics, Types and Tools for Concurrent System Modelling. Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology 1392. 60 pp. Uppsala: Acta Universitatis Upsaliensis. ISBN 978-91-554-9628-9. A concurrent system is a computer system with components that run in parallel and interact with each other. Such systems are ubiquit...