Teaching Coloured Petri Nets - a Gentle Introduction to Formal Methods in a Distributed Systems Course

This paper is about the two compulsory project assignments set to the students in an undergraduate course on distributed systems. In the first assignment the students design and validate a non-trivial layered protocol by means of Coloured Petri Nets, and in the second they implement the designed protocol in an object-oriented language. From the two assignments the students experience that Coloured Petri Nets, as a formal method, are useful for designing and analysing distributed systems. In the course students are introduced to basic concepts and techniques for distributed systems, and it is explained that such systems are often too complex to manage without using formal methods. In this paper we also report on our experience with teaching the course and describe the didactic methods applied. Based on the obtained experience we conclude that the combination of distributed systems and Coloured Petri Nets is fruitful --- the two areas complement each other. Although our experiences origin in Coloured Petri Nets, we believe that many of our observations hold for other formal methods as well.Topics. Education issues related to nets; Coloured Petri Nets; distributed systems; experience with using nets,case studies; applications of nets to protocols

Identitets-, Byggelinie- og Servitutattest

En Identitet-, Byggelinie- og Servitutattest er en attest, som anvendes til at atteste-re for et byggeris lovlige placering. Attesten knytter sig til et behov og der gives ingen retningslinjer i nogen lov, der præciserer, hvordan attesten skal udarbejdes. Attesten har i praksis opnået en grad af udbredelse, der gør, at det synes væsentligt at undersøge, hvorledes attestens anvendelse og indhold forholder sig til lan-dinspektørens professionelle ansvar. Derfor valgte en specialegruppe på Aalborg Universitet i foråret 2017 at undersøge emnet og denne artikel er blevet til i et efterfølgende samarbejde mel-lem specialegruppen og Aalborg Universitet med henblik på at formidle resultaterne. Undersøgelsen blev bygget op omkring den juridiske metode, hvilket afspejles i artiklen, der på denne ene side undersøger praksis og på den anden side reglen

Macroscopic Hematuria and a Bladder Mass: Eosinophilic Cystitis in a 7-Year-Old Boy

We report a case of eosinophilic cystitis in a 7-year-old boy with a history of atopic symptoms, with focus on the radiological findings. He presented with hematuria and dysuria and ultrasonography (US) showed irregular bladder wall thickening resembling a bladder mass. CT urography did not characterize the lesion any further and showed no local or distant spread. Biopsies revealed eosinophilic cystitis, a benign inflammatory condition. We found that US characterized the lesion at least as well as CT and should be the first choice of imaging. When staging is considered before biopsy, MRI should be preferred to CT. There are no specific radiological signs of eosinophilic cystitis. On follow-up, US was a safe, cost-effective imaging modality, but findings should be interpreted in a clinical context. In a child with hematuria and a bladder mass, eosinophilic cystitis is a relevant but rare differential diagnosis, especially when there is a known atopic history