Welcome to the fourth regular issue in 2017 which presents three high quality papers. I'd like to emphasize that this would not be possible without the financial support of the J.UCS consortium and the valuable work and feedback of the members of our editorial board. We are continuously looking for experienced and motivated experts to extend our editorial board so if you are a tenured Associate Professor or above with a good publication record, please do apply for a membership in our editorial board. Please get also in touch with me if your university is interested in joining the consortium and further support the journal.

In this regular issue, I am very glad to introduce three accepted high quality papers from authors of four different countries.

In a collaborative work between Russia and USA, Marat Faizrahmanov, Iskander Kalimullin, Antonio Montalban and Vadim Puzarenko study the Σ-reducibility and discuss the least Σ-jump inversion theorem for n-families. María-Blanca Ibáñez, Soledad Escolar, Ricardo Iskandar, Karen Viera and Carlos Delgado-Kloos report about their research study aiming at exploring the educational usefulness of integrating data captured by wearable biomedical sensors in a simulation learning environment for children. Monika Kapus-Kolar from Slovenia proposes in her work a weaker precondition under which the transformation remains fault-coverage-preserving in the context of optimization of test sets for black-box conformance testing of objects specified and modelled as a finite state machine.

Enjoy reading!

Cordially,

Christian Gütl, Managing Editor
Graz University of Technology, Graz, Austria
Email: cguetl@iicm.edu