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In this work, a rolling simulation system for the hot rolling of steel is elaborated. The system is capable of simulating rolling of slabs and blooms, as well as round or square billets, in different symmetric or asymmetric forms in continuous, reversing, or combined rolling. Groove geometries are user-defined and an arbitrary number of rolling stands and distances between them may be used. A slice model assumption is considered, which allows the problem to be efficiently coped with. The related large-deformation thermomechanical problem is solved by the novel meshless Local Radial Basis Function Collocation Method. A compression test is used to compare the simulation results with the Finite Element Method. A user-friendly rolling simulation application has been created for the industrial use based on C# and .NET framework. Results of the simulation, directly taken from the system, are shown for each type of the rolling mill configurations.

We introduce our 'Kalibri Next Generation' project, the transponder concepts developed in this scope and present technical solutions to meet the challenges of future SAR missions.

Podjetja težijo k čim hitrejšemu in zanesljivemu merjenju izdelkov, ki je hkrati ekonomično ugodno. Zato se v določenih primerih poslužijo merilnih priprav, s katerimi omogočijo ekonomično ugodnejše meritve pri nadzoru geometrijskih značilnosti večje količine izdelkov. V ta namen smo se v podjetju Unior d.d. odločili za izdelavo zasnove merilne priprave, ki bi bila najprimernejša za merjenje tankostenskega odkovka s specifičnimi geometrijskimi zahtevami. V nalogi sem na osnovi definiranih dimenzij in toleranc določil geometrijske značilnosti kalibrov za preverjanje pozicij izvrtin in analiziral odstopanja centrov izvrtin že izdelanih izdelkov. Na osnovi izvedene analize sem skonstruiral tri variante, katere smo na podlagi lastnih ocenjevalnih kriterijev ocenili. Izbrali smo konstrukcijsko in cenovno najbolj ugodno rešitev ki je predstavljena, na koncu diplomskega dela. Companies are tilting to fast and reliable product measurements, which are also cost efficient. Therefore, special measuring appliances, securing cost efficient measurement of bigger number of pieces are widely used. For that purpose, in company Unior d.d. was decided to design a measuring appliance, which will be most suitable for checking geometric characteristics of a thin-walled forged part with specific geometrical characteristics. In the thesis, I have calculated geometrical characteristics of plug gauges for inspecting hole positions, analyzed deviations of previous parts and designed three models, which were evaluated based on our own criteria. Chosen model with the most suitable design and economical efficiency, is presented at the end of the thesis.

The technological advancement of the synthetic aperture radar (SAR) principle leads to an innovative challenge for the calibration as well. In order to provide an active reference target for an accurate absolute radiometric calibration the knowledge of the target’s backscattering characteristics is essential. For the recently developed DLR C-band transponder named “Kalibri” several strategies for an accurate determination of the radar cross section (RCS) have been analyzed. Based on a comparison with respect to accuracy and feasibility, several recommendations for the best transponder calibration strategy were established. The resulting RCS of the transponders retrieved from the most suitable measurement method is presented as well as a cross-validation to prove the plausibility of these results.