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The lack of specific standards for characterization of materials manufactured by Fused Deposition Modelling (FDM) makes the assessment of the applicability of the test methods available and the analysis of their limitations necessary; depending on the definition of the most appropriate specimens on the kind of part we want to produce or the purpose of the data we want to obtain from the tests. In this work, the Spanish standard UNE 116005:2012 and international standard ASTM D638–14:2014 have been used to characterize mechanically FDM samples with solid infill considering two build orientations. Tests performed according to the specific standard for additive manufacturing UNE 116005:2012 present a much better repeatability than the ones according to the general test standard ASTM D638–14, which makes the standard UNE more appropriate for comparison of different materials. Orientation on-edge provides higher strength to the parts obtained by FDM, which is coherent with the arrangement of the filaments in each layer for each orientation. Comparison with non-solid specimens shows that the increase of strength due to the infill is not in the same proportion to the percentage of infill. The values of strain to break for the samples with solid infill presents a much higher deformation before fracture.

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Industry 4.0 in the contemporary operating context carries important sources of complexity. This context generates both traditional risks and emerging risks that must be managed. The management of these risks includes both industrial risks and occupational risks, since they are heavily interlinked. The human factor can be considered the main link between both types of risks. Thus, understanding risks originating from human errors and organizational weaknesses as causes of accidents and other disruptions in complex systems requires elaborating sophisticated modeling approaches. Therefore, the objective of this paper is to propose an organizational and human performance approach to improve the emerging risk management linked to the complex systems, like as Human-Machine Interactions (HMI) and Human-Robot Interaction (HRI). To fulfill this objective, we first introduce the concept of emerging risk linked to human factor. Then, we introduce the concept of emerging risk management in the Industry 4.0 context. Under this complex context, we expose the concept considering the current models of risk management. Finally, we discuss how enhancing human and organizational performance can be achieved through risk management in complex systems linked to Industry 4.0. Therefore, we conclude that while Industry 4.0 brings numerous advantages, it must contend with emerging risks and challenges associated with organizational and human factors. These emerging risks include industrial risks as well as occupational risks. Moreover, the human factor aspect of Industry 4.0 is directly linked to industrial emerging and occupational emerging via context of operations. To cope with these new challenges, it is necessary to develop new approaches. One of such approaches is Complex System Governance. This approach is discussed along with the need for adequate organizational and human performance models dealing with, for example, experience from other domains such as nuclear, space, aviation, and petrochemical.

We report the temperature dependence of Alo.~lno.54As photoluminescence (PL) transition energies and Alo.461no 54As/lnP interface staggered line-up luminescence (SLL) energy. The S shape appearing from 4 to 90 i< on iiie energy versus iemperaiure curves oi iiiese P i energies is due io extrinsic recombinations. In particular, the S shape of the SLL energy curve versus temperature is probably due to acceptor impurities localized in AllnAs, at the inteltace (on-edge impurities). The binding energy of on-edge impurities is lower than its value in the bulk material. This explains why the S shape is less pronounced on the SLL than on the AllnAs PL curve. The band offsets were self-consistent calculation program. At 4.5 K, the conduction and valence band offsets of the Alo.461no.54As/lnP interface were respectively 0.384 eV and 0.295 eV. This is in agreement with the already reported value of 4lO.meV for the conduction band offset of the latticematched Alo.alno.s2As/lnP heterostructure. The temperature dependence of the conduction and valence band offsets is shown to be important: respectively 35 meV and 23 meV between 4.5 and 300 K. The Van Vechten-Malloy model (following a thermodynamic approach) for the temperature dependence of the band offsets i s compared with our results. The comparison shows only a qualitative agreement.