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This work aims to provide additional insights regarding the practicability of using conventional materials in the fused filament fabrication (FFF) process.

Two different acrylonitryle butadiene styrene (ABS) grades are studied and compared, aiming to check to what extent the regular ABS developed for conventional polymer processing, with a different rheology than the one provided for the FFF process, can also be used in this process (FFF).

The rheological results show that a general-purpose ABS (ABS-GP) melt is much more viscous and elastic than ABS-FFF. It is clear that using ABS-GP as feedstock material in the FFF process results in poor coalescence and adhesion between the extruded filaments, which has a detrimental effect on the mechanical properties of the printed specimens. Despite its lower performance, ABS-GP can be a good choice if the objective is to produce an aesthetical prototype. If the objective is to produce a functional prototype or a final part, its mechanical performance requirements will dictate the choice.

This work provides insightful information regarding the use of high viscosity materials on the 3D printing process.

The purpose of this paper is to develop new boundary conditions for simulating the injection molding process of polymer melts.

The boundary conditions are derived and implemented to simulate real-life air vents (used to allow the air escape from the mold). The simulations are performed in the computational library OpenFOAM® by considering two different fluid models, namely, Newtonian and generalized Newtonian (Bird–Carreau model).

A detailed study on the accuracy of the solver interFoam for simulating the filling stage is presented, by considering simple geometries and adaptive mesh refinement. The verified code is then used to study the three-dimensional filling of a more complex geometry.

The results obtained showed that the numerical method is stable and allows one to model the filling process, simulating the real injection molding process.

The purpose of this paper is to analyze how, in three different contexts, the National Council for Advertising Self-Regulation narratively uses its past to build an official history concerning its origins that legitimates advertising self-control as a hegemonic narrative.

By using the historical research and the “uses of the past” approach, this study identifies, analyzes and confronts three organizational histories of Conar’s origins (both its official and unofficial versions) in the context of the creation of the Brazilian system of advertising self-regulation.

After a thematic analysis of the documentary sources, the narratives on the National Council for Advertising Self-Regulation’s origins and the self-control process were grouped into three versions: the narrative under the military regime: 1976/1980; the narrative during the process of re-democratization of the country: 1981/1991 and the contemporary narrative: from 2005 onwards. These narratives were confronted and, in consequence, provided, each of them, a different interpretation of the context surrounding the creation and justification for advertising self-control.

The study shows how a consumer defense organization re-historicized its past strategically to gain legitimacy in three different ways through time. It also reveals that organizations strategically use their past to build an intended vision of the future, thus having more agency than the hegemonic literature in management studies usually guarantees. Finally, it exposes the malleability of past narratives through which organizations play a critical role in the ongoing struggle for competing uses of the past. Therefore, the study identifies different organizational stories through time that allow researchers to reflect on several strategic uses of the past by organizations.