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Finite element (FE) analysis can be used for both design and verification of components. In the case of 3D-printed materials, a proper characterization of properties, accounting for anisotropy and raster angles, can help develop efficient material models. This study aims to use compression tests to characterize short carbon-reinforced PA12 made by fused filament fabrication (FFF) and to model its behaviour by the FE method.

In this work, the authors focus on compression tests, using post-processed specimens to overcome external defects introduced by the FFF process. The material’s elastoplastic mechanical behaviour is modelled by an elastic stiffness matrix, Hill’s anisotropic yield criterion and Voce’s isotropic hardening law, considering the stacking sequence of raster angles. A FE analysis is conducted to reproduce the material’s compressive behaviour through the LS-DYNA software.

The proposed model can capture stress values at different deformation levels and peculiar aspects of deformed shapes until the onset of damage mechanisms. Deformation and damage mechanisms are strictly correlated to orientation and raster angle.

The paper aims to contribute to the understanding of 3D-printed material’s behaviour through compression tests on bulk 3D-printed material. The methodology proposed, enriched with an anisotropic damage criterion, could be effectively used for design and verification purposes in the field of 3D-printed components through FE analysis.

This paper aims to provide a full introduction, new classification, comparison and investigation of the challenges as well as applications of layerless 3D printing, which is one of the industry 4.0 pioneers.

Given the significance and novelty of uniform 3D printing, more than 250 publications were collected and reviewed in an unbiased and clear manner.

As a result, the majority of uniform parts printed in polymer form are known up to this point. In a novel division for better researchers’ comprehension, uniform printing systems were classified into three categories: oxygen inhibition (OI), liquid lubrication (LL) and photon penetration (PP), and each was thoroughly investigated. Furthermore, these three approaches were evaluated in terms of printing speed, precision and accuracy, manufacturing scale and cost.

The parameters of each approach were compared independently, and then a practical comparison was conducted among these three approaches. Finally, a variety of technologies, opportunities, challenges and advantages of each significant method, as well as a future outlook for layerless rapid prototyping, are presented.

The purpose of this study was to explore the perceptions of internally displaced persons regarding their experiences with various human rights prescripts. This study also sought to contribute to the literature on the living conditions of internally displaced persons and narrow the gap in internal displacement studies, particularly in sub-Saharan Africa.

A case study approach and quantitative research paradigm were adopted in the study. A questionnaire was used to collect data from 584 participants in Niger State, Edo State and Kaduna State in Nigeria.

The findings reveal that most of the internally displaced persons were youth, unemployed and had a strong motivation to meet their physiological needs. The empirical evidence in this study leads to the conclusion that the daily struggle of the participants to meet their survival needs overshadows every other human rights consideration among them.

Various practical and theoretical implications are inferred from this study including the imperative to urgently address the causes of internal displacement and provide urgent assistance to internally displaced persons.

Besides the novel conceptual insights and empirical data, this study makes unique contributions to literature on internally displaced persons and human rights theory.