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This paper aims to report on the findings of an investigation to compare three different three-dimensional printing (3DP) or additive manufacturing technologies [i.e. fused deposition modeling (FDM), stereolithography (SLA) and material jetting (MJ)] and four different equipment (FDM, SLA, MJP 2600 and Object 260) in terms of their dimensional process capability (dimensional accuracy and surface roughness). It provides a comprehensive and comparative understanding about the level of attainable dimensional accuracy, repeatability and surface roughness of commonly used 3DP technologies. It is expected that these findings will help other researchers and industrialists in choosing the right technology and equipment for a given 3DP application.

A benchmark model of 5 × 5 cm with several common and challenging features, such as around protrusion and hole, flat surface, micro-scale ribs and micro-scale long channels was designed and printed repeatedly using four different equipment of three different 3DP technologies. The dimensional accuracy of the printed models was measured using non-contact digital measurement methods. The surface roughness was evaluated using a digital profilometer. Finally, the surface quality and edge sharpness were evaluated under a reflected light ZEISS microscope with a 50× magnification objective.

The results show that FDM technology with the used equipment results in a rough surface and loose dimensional accuracy. The SLA printer produced a smoother surface, but resulted in the distortion of thin features (<1 mm). MJ printers, on the other hand, produced comparable surface roughness and dimensional accuracy. However, ProJet MJP 3600 produced sharper edges when compared to the Objet 260 that produced round edges.

This paper, for the first time, provides a comprehensive comparison of three different commonly used 3DP technologies in terms of their dimensional capability and surface roughness without farther post-processing. Thus, it offers a reliable guideline for design consideration and printer selection based on the target application.

In total, 19 practices of circular economy divided into three groups, internal environmental management, ecological design and investment recovery were studied in a local network composed of small companies and individual entrepreneurs related to common product and by-product flows. The paper aims to discuss these issues.

This research presents an applied nature, is characterized as exploratory and adopted the case study as a technical procedure using sources and methods of data collection. The primary data were collected through direct observation of the processes and semi-structured interviews with managers and owners.

The most widespread practices are related to product design. However, in most cases, the implementation was punctual and did not present continuous and corresponding actions, which highlights the embryonic contours of European Commission (EC) in the observed network. The practices from the management category were less observed, which revels the environmental variable is not included in the strategic business planning.

The research documents the application of CE practices in a local network and brings this current paradigm shift to the Brazilian context.

To overcome barriers to the implementation of EC practices, it is suggested to restructure commercial relations, to formulate public policies and to develop infrastructures that facilitate the materiality of flows and the market.

The study highlights the need of public policies that promotes cross-sectoral cooperation in accordance with NSWP objectives.

Despite the focus on EC implemented practices this study offers a framework of the research routes on the main barriers and suggests actions to overcome the challenges in the transition from the economy to the circular model.

The emergence of COVID-19 has exacerbated and spurred the growth of mental health issues in ways that have challenged mental health workers tremendously. The complex nature of COVID-19 has made the need of mental health professionals extremely important. Hospital ward overcrowding, social distancing requirements, sequestrations, limits to face-to-face consultations have created barriers to mental health access, especially those in need of Certified Peer Recovery Specialists. Certified Peer Recovery Specialists play a critical role in the treatment of mental illness through their support and engagement of those recovering from substance abuse. Many in this role are hired because they have a strong skillset for help-oriented clinical work but are often challenged, especially in times like this to development and demonstrate leadership skills. This paper explores the nature and need to develop leadership skills and leadership challenges for people in this field through interpretative phenomenological analysis (IPA) and a content analysis of the current and seminal literature.

This paper explores the nature and need to develop leadership skills and leadership challenges for people in mental health through IPA and a content analysis of the current and seminal literature.

The essential necessity to invest in the cultivation of peer recovery specialists and mental health professionals as organizational leaders.

Hospital ward overcrowding, social distancing requirements, sequestrations, limits to face- to- face consultations have created barriers to mental health access, especially those in need of Certified Peer Recovery Specialists. Certified Peer Recovery Specialists play a critical role in the treatment of mental illness through their support and engagement of those recovering from substance abuse.

The physical internet (PI) is an emerging logistics and supply chain management (SCM) concept that draws on different technologies and areas of research, such as the Internet of Things (IoT) and key performance indicators, with the purpose of revolutionizing existing logistics and SCM practices. The growing literature on the PI and its noteworthy potential to be a disruptive innovation in the logistics industry call for a systematic literature review (SLR), which we conducted that defines the current state of the literature and outlines future research directions and approaches.

The SLR that was undertaken included journal publications, conference papers and proceedings, book excerpts, industry reports and white papers. We conducted descriptive, citation, thematic and methodological analyses to understand the evolution of PI literature.

Based on the literature review and analyses, we proposed a comprehensive framework that structures the PI domain and outlines future directions for logistics and SCM researchers.

Our research findings are limited by the relatively low number of journal publications, as the PI is a new field of inquiry that is composed primarily of conference papers and proceedings.

The proposed PI-based framework identifies seven PI themes, including the respective facilitators and barriers, which can inform researchers and practitioners on future potentially disruptive SC strategies.

In Italy, worker cooperatives (WCs), whose workers hold major control rights over collectively-owned assets, are the leading vehicle for the promotion and development of employee ownership. Worker cooperatives are present in all regions and in most economic sectors, employing about 506,000 workers and generating a turnover of about €22 bn. Despite their history and diffusion, the high prevalence of WCs in Italy is under-researched and -thematised and requires new research.

The paper leverages unpublished primary and secondary data from Centro Studi Legacoop databank, the Aida-Bureau Van Dijk databank and the Cooperative Registry of the Ministry of Economic Development (CRMED) to explain the spread of WCs in Italy.

This paper reveals descriptive statistics of WCs and investigates their distribution across economic sectors and regions, their economic and financial performance and gives an overview of the relevant legislation. The paper indicates that older small- and medium-sized cooperatives located in central and north-eastern Italy perform best economically. However, in recent years, an increasing number of young cooperatives has emerged in South Italy thanks to favourable legislation, cooperative finance and the diffusion of cooperative know-how. Limitations to such results are reported in the conclusions.

The paper sheds light on past and recent development trends of WCs in Italy, highlights their growth in South Italy and revitalises the debate on the drivers, structures and rationales of employee-owned enterprises in Italy. Findings generate implications for research and practice. Given the tendency of WCs to better protect jobs than investor-owned enterprises, the spread of these enterprises may help workers find better and more stable jobs, counter-cyclically mitigating the dangerous effects of macro- and meso-economic fluctuations and instability.

The material extrusion (ME) process induces variations in the final part’s microscopic and macroscopic structural characteristics. This viewpoint article aims to uncover the relation between ME fabrication parameters and the microstructural and mesostructural characteristics of the ME BASF Ultrafuse Steel 316L metal parts. These characteristics can affect the structural integrity of the produced parts and components used in various engineering applications.

Recent studies on the ME BASF Ultrafuse Steel 316L are reviewed, with a focus on those which report microstructural and mesostructural characteristics that may affect structural integrity.

A relationship between ME fabrication parameters and subsequent microstructural and mesostructural characteristics is discussed. Common microstructural and mesostructural/macrostructural defects are also highlighted and discussed.

This viewpoint article attempts to bridge the existing gap in the literature, highlighting the influence of ME fabrication parameters on Steel 316L parts fabricated via this additive manufacturing method. Moreover, this article identifies and discusses important considerations for the purposes of selecting and optimising the structural integrity of ME-fabricated Steel 316L parts.

The wide application of metal material extrusion (MEX) has been hampered by the practicalities associated with the resulting shrinkage of the final parts when commercial three-dimensional (3D) printing equipment is used. The shrinkage behaviour of MEX metal parts is a very important aspect of the MEX metal production process, as the parts must be accurately oversized to compensate for shrinkage. This paper aims to investigate the influence of primary 3D printing parameters, namely, print speed, layer height and print angle, on the shrinkage behaviour of MEX Steel 316L parts.

Two groups of dog-bone and rectangular-shape specimens were produced with the BASF Ultrafuse Steel 316L metal filament. The length, width and thickness of the specimens were measured pre- and post-debinding and sintering to calculate the percentile shrinkage rates. Analysis of variance (ANOVA) was used to evaluate and rank the significance of each manufacturing parameter on shrinkage. Typical main print quality issues experienced in this analysis are also reported.

The shrinkage rates of the tested specimens ranged from 15.5 to 20.4% along the length and width axis and 18.5% to 23.1% along the thickness axis of the specimens. Layer height and raster angle were the most statistically significant parameters influencing shrinkage, while print speed had very little influence. Three types of defects were observed, including surface roughness, surface deformation (warping and distortion) and balling defects.

This paper bridges an existing gap in MEX Steel 316L literature, with a focus on the relationship between MEX manufacturing parameters and subsequent shrinkage behaviour. This study provides an in-depth analysis of the relationship between manufacturing parameters – layer height, raster angle and print speed and subsequent shrinkage behaviour, thereby providing further information on the relationship between the former and the latter.