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The forensic scenario, on which the round robin study was based, simulated a suspected intentional manipulation of a real estate rental agreement consisting of a total of three pages. The aims of this study were to (i) establish the amount and reliability of information extractable from a single type of evidence and to (ii) provide suggestions on the most suitable combination of compatible techniques for a multi-modal imaging approach to forgery detection. To address these aims, seventeen laboratories from sixteen countries were invited to answer the following tasks questions: (i) which printing technique was used? (ii) were the three pages printed with the same printer? (iii) were the three pages made from the same paper? (iv) were the three pages originally stapled? (v) were the headings and signatures written with the same ink? and (vi) were headings and signatures of the same age on all pages? The methods used were classified into the following categories: Optical spectroscopy, including multispectral imaging, smartphone mapping, UV-luminescence and LIBS ; Infrared spectroscopy, including Raman and FTIR (micro-)spectroscopy ; X-ray spectroscopy, including SEM-EDX, PIXE and XPS ; Mass spectrometry, including ICPMS, SIMS, MALDI and LDIMS ; Electrostatic imaging, as well as non- imaging methods, such as non-multimodal visual inspection, (micro-)spectroscopy, physical testing and thin layer chromatography. The performance of the techniques was evaluated as the proportion of discriminated sample pairs to all possible sample pairs. For the undiscriminated sample pairs, a distinction was made between undecidability and false positive claims. It was found that none of the methods used were able to solve all tasks completely and/or correctly and that certain methods were a priori judged unsuitable by the laboratories for some tasks. Correct results were generally achieved for the discrimination of printer toners, whereas incorrect results in the discrimination of inks. For the discrimination of paper, solid state analytical methods proved to be superior to mass spectrometric methods. None of the participating laboratories deemed addressing ink age feasible. It was concluded that correct forensic statements can only be achieved by the complementary application of different methods and that the classical approach of round robin studies to send standardised subsamples to the participants is not feasible for a true multimodal approach if the techniques are not available at one location.

Prema iskustvu, procjena požarne otpornosti čeličnih elemenata prema europskim normama je konzervativna, a napredne metode proračuna su složene i dugotrajne. U sklopu međunarodne Round Robin studije, procjena postojećih metoda analizirana je za ispitani čelični nosač izložen savijanju i standardnom ISO požaru. Usporedba rezultata pokazuje da napredne metode daju neujednačene procjene. Svejedno, napredne su metode proračuna potrebne za poboljšanje normiranih metoda koje precjenjuju požarnu otpornost ovog "trivijalnog" problema., Experience shows that the assessment of fire resistance of steel elements based on European standards is conservative, while advanced methods are complex and time consuming. The analysis of existing methods for the tested steel beam exposed to bending and standard ISO fire was conducted in the scope of the international Round Robin study. The comparison of results shows that advanced methods provide non-uniform assessments. Nevertheless, advanced methods are necessary for improving standard methods that overestimate fire resistance of this "trivial" problem.

With its ability to fabricate fully dense three-dimensional structures by selectively melting micro-sized metal powder, the additive manufacturing process of laser beam melting (LBM) is considered by many to be a significant technology that is complementary to the conventional forming and subtractive manufacturing processes. However, even with its ability to fabricate structures with characteristics comparable to conventional fabrication, the LBM process often lacks the consistency and degree of repeatability essential for its industrial acceptance for certain end-product applications. Inconsistency in the characteristics of structures is often related to a combination of variations in system technology, process, and user influence. In order to understand fully the potential and limitations of the LBM process, the paper discusses the design, methodology, and results of a round robin test conducted within the Collaborative Working Group (CWG) lasers in production at the International Academy of Production Engineering (CIRP). Observed mechanical characteristics for samples from each of the participants are presented. The experiments are designed to obtain data related to mechanical characteristics for different build orientations and processing conditions in addition to the inherent system technology variations. The paper further discusses the observed process phenomena and their association with the induced mechanical characteristics.