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Fused Filament Fabrication (FFF) is an extrusion-based manufacturing process using fused thermoplastics. Despite its low cost, the FFF is not extensively used in high-value industrial sectors mainly due to parts' anisotropy (related to the deposition strategy) and residual stresses (caused by successive heating cycles). Thus, this study aims to investigate the process improvement and the optimization of the printed parts.

In this work, a meshless technique – the Radial Point Interpolation Method (RPIM) – is used to numerically simulate the viscoplastic extrusion process – the initial phase of the FFF. Unlike the FEM, in meshless methods, there is no pre-established relationship between the nodes so the nodal mesh will not face mesh distortions and the discretization can easily be modified by adding or removing nodes from the initial nodal mesh. The accuracy of the obtained results highlights the importance of using meshless techniques in this field.

Meshless methods show particular relevance in this topic since the nodes can be distributed to match the layer-by-layer growing condition of the printing process.

Using the flow formulation combined with the heat transfer formulation presented here for the first time within an in-house RPIM code, an algorithm is proposed, implemented and validated for benchmark examples.

The purpose of this paper is to apply the concept of equivalent initial flaw size (EIFS) to the anisotropic nickel-based single crystal (SX) material, and to predict the fatigue life on this basis. The crack propagation law of SX material at different temperatures and the weak correlation of EIFS values verification under different loading conditions are also investigated.

A three-parameter time to crack initial (TTCI) method with multiple reference crack lengths under different loading conditions is established, which include the TTCI backstepping method and EIFS fitting method. Subsequently, the optimized EIFS distribution is obtained based on the random crack propagation rate and maximum likelihood estimation of median fatigue life. Then, an effective driving force based on anisotropic and mixed crack propagation mode is proposed to describe the crack propagation rate in the small crack stage. Finally, the fatigue life of three different temperature ESE(T) standard specimens is predicted based on the EIFS values under different survival rates.

The optimized EIFS distribution based on EIFS fitting - maximum likelihood estimation (MLE) method has the highest accuracy in predicting the total fatigue life, with the range of EIFS values being about [0.0028, 0.0875] (mm), and the mean value of EIFS being 0.0506 mm. The error between the predicted fatigue life based on the crack propagation rate and EIFS distribution for survival rates ranges from 5% to 95% and the experimental life is within two times dispersion band.

This paper systematically proposes a new anisotropic material EIFS prediction method, establishing a framework for predicting the fatigue life of SX material at different temperatures using fracture mechanics to avoid inaccurate anisotropic constitutive models and fatigue damage accumulation theory.

This paper aims to provide SIF calculation method for engineering application.

In this paper, the stress intensity factors (SIFs) calculation method is applied to the anisotropic Ni-based single crystal film cooling holes (FCHs) structure.

Based on contour integral, the anisotropic SIFs analysis finite element method (FEM) in Ni-based single crystal is proposed. The applicability and mesh independence of the method is assessed by comparing the calculated SIFs using mode of plate with an edge crack. Anisotropic SIFs can be calculated with excellent accuracy using the finite element contour integral approach. Then, the effect of crystal orientation and FCHs interference on the anisotropic SIFs is clarified. The SIFs of FCH edge crack in the [011] orientated Ni-based single crystal increases faster than the other two orientations. And the SIF of horizontal interference FCHs edge crack is also larger than that of the inclined interference one.

The SIFs of the FCH edge crack in the turbine air-cooled blade are innovatively computed using the sub-model method. Both the Mode I and II SIFs of FCHs edge crack in blade increase with crack growing.

This chapter examines the internationalisation of public higher education in Brazil using the theoretical triptych of internationalisation as developed by leading scholars in the field: internationalisation at home (IaH), internationalisation abroad (IA), and internationalisation at a distance (IaD). This framework – while rooted in knowledge, systems, and scholarship from researchers and institutions in the Global North – is a constructive tool for categorising and understanding internationalisation at Brazil’s higher education institutions (HEIs) when coupled with an exploration of the history, context, policy, and dynamics of internationalisation efforts. The chapter then summarises and underscores recent and important scholarship by Brazilian researchers and others in the Global South that describes the history of the nation’s internationalisation efforts. It also critiques the powerful influence that Global North-centred objectives and priorities for internationalisation have on the process at Brazilian HEIs. Following a discussion of the theoretical framework and relevant literature, the chapter provides a case study of internationalisation efforts and initiatives of an elite public university, the Universidade Federal de Minas Gerais (UFMG). Content analysis of UFMG’s website and publicly available reports and data demonstrates a high level of institutional internationalisation that has unfolded in recent years, stimulated by federal funding and guided by a strategic framework developed within the Ministry of Education. An analysis of UFMG’s mission, partnerships and programmes finds that the institution serves as an example of internationalisation in Brazil’s public higher education context, as its programmes and initiatives exemplify the overarching objectives of internationalisation in Brazilian higher education.

In our studies of daily newspapers and news websites in small and medium-sized cities in Brazil, we view these enterprises as firms endowed with specific strengths and weaknesses reflecting the characteristics of the localities in which they operate. In addition, we use references from urban geography and the industrial economy to investigate their structure, conduct, and performance. This chapter presents our observations about the structure of these firms and the journalistic business in non-metropolitan cities of the State of Rio de Janeiro. The results point to greater consolidation of newspapers, despite their traditional way of operating; the low performance of news websites and their restricted source of revenue; and the existence of a potential regional market little explored by these media.

In a world teeming with concurrent processes and associated chaos, organizational working procedures have adapted to new trends; employees must keep up with everything while maintaining their mental health. Spirituality lends a person's life significance. Spirituality in the workplace can both physically and psychologically engage employees. Spirituality in the workplace is reflected in the organizational culture, which is founded on fundamental values such as trust, honesty, appreciation, innovation, care, respect, and loyalty. Workplace spirituality encompasses the pursuit of one's ultimate purpose in life, the development of a solid connection to colleagues and other people associated with work, and the consistency or alignment between one's fundamental beliefs and the organization's values. To have a competitive advantage and attract the best personnel, an organization's working environment must be based on strong ethical and spiritual values such as compassion, integrity, respect, harmony, trust, teamwork, and forgiveness, among others.

The purpose of this scoping review is to analyse comparative studies on social-policy measures implemented during the COVID-19 pandemic in Global North welfare states. The authors also consider the potential influence of the regimes on the responses.

The authors conducted a scoping review of six databases including peer-reviewed comparative studies. In an iterative process with exact inclusion criteria, the authors screened 699 titles/abstracts/articles and found 16 comparative research articles to be included in the review and analysis. The review summarises the main themes of the comparative articles and the articles' typical features.

The results show that social-policy measures were directed specifically at working-age people to minimise income loss and to save jobs. The pandemic also increased care-related responsibilities, necessitating the expansion of current policies and the implementation of new instruments. Despite the differences in responses between universalistic and residual welfare states, the influence of welfare regimes on COVID-19 social-policy measures remains unclear. The emergency responses in the different regimes varied widely in terms of coverage.

The results of this review provide a basis on which to conduct future studies, identify new research topics and knowledge gaps and inspire new research questions and hypotheses. Given the accumulation of scientific knowledge in the area of social-policy measures, the need for systematic reviews will grow in the future.

The authors identified three main themes: changes in employment protection, changes in care-related income protection and the potential influence of welfare-state regimes on COVID-19-related measures.

Most scientific research has focused on understanding Ponzi schemes from the point of view of the schemes and their operators, based on qualitative analysis. This paper aims to analyze Ponzi schemes from the perspective of their investors, emphasizing behavioral aspects, which have been little explored in the scientific literature, especially in quantitative research. In this way, the authors sought to understand the effects of heuristics and cognitive biases in understanding investor behavior.

A logistic regression was carried out with Brazilian investors, some of them participants in Ponzi schemes, who answered a structured questionnaire by means of a survey.

The authors found that social pressures, overconfidence and deliberate ignorance lead to credulity, generating little risk analysis and the desire to make a lot of money quickly.

Helping investors improve their levels of information through financial education and self-knowledge about their behavior. Contribute to the competent authorities in the search for improvements in the information displayed to investors.

Understanding the mechanisms used when making a financial decision from the point of view of investors in general, but especially those exposed to Ponzi schemes, has the mission of enlightening them about the importance of financial education and the weight of psychological factors so that they can reduce the effects of heuristics and analysis biases when faced with a financial decision.

The basis of this work will be the inclusion of psychological variables and financial education, adapting existing models in an attempt to demonstrate the effects they may or may not have on mental accounting in the specific case of investors