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The purpose of this paper is to present a Design for Additive Manufacturing (DfAM) methodology that connects several methods, from geometrical design to post-process selection, into a common optimisation framework.

A design methodology is formulated and tested in a case study. The outcome of the case study is analysed by comparing the obtained results with alternative designs achieved by using other design methods. The design process in the case study and the potential of the method to be used in different settings are also discussed. Finally, the work is concluded by stating the main contribution of the paper and highlighting where further research is needed.

The proposed method is implemented in a novel framework which is applied to a physical component in the case study. The component is a structural aircraft part that was designed to minimise weight while respecting several static and fatigue structural load cases. An addition goal is to minimise the manufacturing cost. Designs optimised for manufacturing by two different AM machines (EOS M400 and Arcam Q20+), with and without post-processing (centrifugal finishing) are considered. The designs achieved in this study show a significant reduction in both weight and cost compared to one AM manufactured geometry designed using more conventional methods and one design milled in aluminium.

The method in this paper allows for the holistic design and optimisation of components while considering manufacturability, cost and component functionality. Within the same framework, designs optimised for different setups of AM machines and post-processing can be automatically evaluated without any additional manual work.

There is growing scholarly discourse towards COVID-19 pandemic and creative entrepreneurship in the perspectives of Global South. Extant literature lacks sufficient empirical evidence on the subject matter. This paper therefore provides insights into business models and business model shifts in response to the COVID-19 pandemic among creative entrepreneurs in Ghana.

In working towards achieving the purpose of the study, a qualitative design was deployed. Four artistic communities in three regions were understudied. The study conducted working interviews, Focus Group Discussions and field observations on the creative entrepreneurs.

The results showed a unique business model that captured ministries, agencies and departments; traditional authorities, foreigners and the diaspora community as key creative partners. The creative entrepreneurs equally proposed value via quality deliveries, attractive pattern mix, pure handy crafts, mart finishing, imbibing culture into productions and symbolic meanings. Their key activities include cutting and gluing, sewing and coloring, sketching and prototyping, annual Kente festivals, film shooting and editing. The creatives stream revenue through sales, advances, profit margins, contracts, gate proceeds, loans, friends and family support. The results also point at a regime of business model shifts among the creatives, deploying digitalization and diversification in response to the COVID-19 pandemic.

The research by design is limited to the qualitative tradition; despite knowing well about the quantitative approach that could have provided a wider scope and coverage for effective generalizability. Certainly, it would be of future research interest to design a comparative mix-method study to achieve a wider coverage feat. Indeed, the paper does achieve the goal of providing an original empirical account, hence making a valid contribution to knowledge in the area of study.

The knowledge on demystified business models relative to the Ghanaian creative entrepreneurs has practical implications for practice: first, it generates a ground-up knowledge as to what creative entrepreneurial business models are, why they exist and exactly how to create one in a Global South perspective.

These creative business models and the COVID-19 induced model shifts among the Ghanaian creative entrepreneurs imply continuous creative livelihoods, sustainable business models and assurance for innovation in creative entrepreneurship space.

The study is of high scientific value, creative entrepreneurial essence and public interest to better demystify creative entrepreneurial business models and theoretically framed them. It offers strong empirical evidence on COVID-19 induced business model shifts. These creative business models and the COVID-19 induced model shifts among the Ghanaian creative entrepreneurs imply continuous creative livelihoods, sustainable business models and assurance for innovation in creative entrepreneurship space.

This paper proposes an approach to solve the vehicle routing problem with simultaneous pickup and delivery (VRPSPD) in the context of the Physical Internet (PI) supply chain. The main objective is to minimize the total distribution costs (transportation cost and holding cost) to supply retailers from PI hubs.

Mixed integer programming (MIP) is proposed to solve the problem in smaller instances. A random local search (RLS) algorithm and a simulated annealing (SA) metaheuristic are proposed to solve larger instances of the problem.

The results show that SA provides the best solution in terms of total distribution cost and provides a good result regarding holding cost and transportation cost compared to other heuristic methods. Moreover, in terms of total carbon emissions, the PI concept proposed a better solution than the classical supply chain.

The sustainability of the route construction applied to the PI is validated through carbon emissions.

This approach also relates to the main objectives of transportation in the PI context: reduce empty trips and share transportation resources between PI-hubs and retailers. The proposed approaches are then validated through a case study of agricultural products in Thailand.

This approach is also relevant with the reduction of driving hours on the road because of share transportation results and shorter distance than the classical route planning.

This paper addresses the VRPSPD problem in the PI context, which is based on sharing transportation and storage resources while considering sustainability.

The coronavirus disease 2019 (COVID-19) epidemic has caused stress for everyone and impacted the lives of people globally. Such stress increases troubles for the employees. Therefore, the aim of the paper is to identify symptoms of health problems that employees face during the COVID-19 epidemic. Also, the aim of the paper is to examine if there are statistically significant differences in the physical, emotional and behavioral symptoms of health problems among employees before the COVID-19 epidemic and employees during the COVID-19 epidemic.

The research is based on a survey of 950 employees in Slovenian companies. The factor analysis and the t-test for two independent samples were used to test the hypotheses of the research.

The results show that physical, emotional and behavioral symptoms of health problems of employees during the COVID-19 epidemic are intensified as compared to the before COVID-19 epidemic era.

The results highlight the measures with which companies can reduce the problem of different symptoms of employees during the COVID-19 epidemic. The results can be useful for employers and for managers who want to create an adequate working environment for employees during the COVID-19 epidemic.

Cloud Manufacturing (CM) is the manufacturing version of Cloud Computing and aims to increase flexibility in the provision of manufacturing services. On-demand manufacturing services can be requested by users to the cloud and this enables the concept of Manufacturing-as-a-Service (MaaS). Given the considerable number of prototypes and proofs of concept addressed in literature, this work seeks real CM platforms to study them from a business perspective, in order to discover what MaaS concretely means today and how these platforms are operating.

Since the number of real applications of this paradigm is very limited (if the authors exclude prototypes), the research approach is qualitative. The paper presents a multiple-case analysis of 6 different platforms operating in the manufacturing field today. It is based on empirical data and inductively researches differences among them (e.g. stakeholders, operational flows, capabilities offered and scalability level).

MaaS has come true in some contexts, and today it is following two different deployment models: open or closed to the provider side. The open architecture is inspired by a truly open platform which allows any company to be part of the pool of service providers, while the closed architecture is limited to a single service provider of the manufacturing services, as it happens in most cloud computing services.

The research shoots a picture of what MaaS offers today in term of capabilities, what are the deployment models and finally suggests a framework to assess different levels of development of MaaS platforms.

The purpose of this paper is to investigate how clients – five years after completing treatment interventions endorsing abstinence – view abstinence and the role of Alcoholics Anonymous (AA) in their recovery process.

Interviews with 40 clients were conducted shortly after them finishing treatment and five years later. All the interviewees had attended treatment programmes based on the 12-step philosophy, and they all described abstinence as crucial to their recovery process in an initial interview.

At follow-up, the majority remained abstinent. For many, attending AA meetings was still important – some described attending as a routine, whereas others stressed that the meetings were crucial for remaining abstinent. For those who reported controlled drinking (CD), this was described either as a natural step in their recovery process or as associated with worries and self-doubts.

The results suggest the importance of offering interventions with various treatment goals and that clients choosing CD as part of their sustained recovery would benefit from support in this process, both from peers and professionals.

There are heterogeneous views on the possibilities of CD after recovery from substance use disorder both in research and in treatment systems. This study on client views on abstinence versus CD after treatment advocating total abstinence can contribute with perspectives on this ongoing discussion.

The purpose of this study is to examine the perceptions of the human resources (HR) function from millennials and postmillennials who are either just finishing college or already in the early stages of their careers. Previous works have often revealed negative stereotypes toward HR, and this study serves to discover whether these perceptions are changing. Further, the study aims to address the origins of and reasoning behind these new perceptions.

A two-study survey research design using a sample of 106 college of business students (Study 1) and an additional sample of 135 former business students who have graduated since 2011 (Study 2) is used.

The results demonstrate that perceptions of HR are changing and quite positive, with the majority of these perceptions originating from personal experiences. In fact, the vast majority of respondents not only felt positive about HR but also like and trust their HR representatives.

Results also suggest that there may be a disconnect between perceptions of the HR function and its actual purpose, suggesting that HR professionals need to better educate others about their important role as a strategic business partner.

This study aims to investigate the effect of vibration on ceramic tools under dry cutting conditions and find the optimum cutting condition for the hardened steel machining process in a computer numerical control (CNC) lathe machine.

In this research, an integrated fuzzy TOPSIS-based Taguchi L9 optimization model has been applied for the multi-objective optimization (MOO) of the hard-turning responses. Additionally, the effect of vibration on the ceramic tool wear was investigated using Analysis of Variance (ANOVA) and Fast Fourier Transform (FFT).

The optimum cutting conditions for the multi-objective responses were obtained at 98 m/min cutting speed, 0.1 mm/rev feed rate and 0.2 mm depth of cut. According to the ANOVA of the input cutting parameters with respect to response variables, feed rate has the most significant impact (53.79%) on the control of response variables. From the vibration analysis, the feed rate, with a contribution of 34.74%, was shown to be the most significant process parameter influencing excessive vibration and consequent tool wear.

The MOO of response parameters at the optimum cutting parameter settings can significantly improve productivity in the dry turning of hardened steel and control over the input process parameters during machining.

Most studies on optimizing responses in dry hard-turning performed in CNC lathe machines are based on single-objective optimization. Additionally, the effect of vibration on the ceramic tool during MOO of hard-turning has not been studied yet.

Polyurethane (PUR) foam parts are traditionally manufactured using metallic molds, an unsuitable approach for prototyping purposes. Thus, rapid tooling of disposable molds using fused filament fabrication (FFF) with polylactic acid (PLA) and glycol-modified polyethylene terephthalate (PETG) is proposed as an economical, simpler and faster solution compared to traditional metallic molds or three-dimensional (3D) printing with other difficult-to-print thermoplastics, which are prone to shrinkage and delamination (acrylonitrile butadiene styrene, polypropilene-PP) or high-cost due to both material and printing equipment expenses (PEEK, polyamides or polycarbonate-PC). The purpose of this study has been to evaluate the ease of release of PUR foam on these materials in combination with release agents to facilitate the mulding/demoulding process.

PETG, PLA and hardenable polylactic acid (PLA 3D870) have been evaluated as mold materials in combination with aqueous and solvent-based release agents within a full design of experiments by three consecutive molding/demolding cycles.

PLA 3D870 has shown the best demoldability. A mold expressly designed to manufacture a foam cushion has been printed and the prototyping has been successfully achieved. The demolding of the part has been easier using a solvent-based release agent, meanwhile the quality has been better when using a water-based one.

The combination of PLA 3D870 and FFF, along with solvent-free water-based release agents, presents a compelling low-cost and eco-friendly alternative to traditional metallic molds and other 3D printing thermoplastics. This innovative approach serves as a viable option for rapid tooling in PUR foam molding.

This paper aims to support small mobile application development teams or companies performing testing on a large variety of operating systems versions and mobile devices to ensure their seamless working.

This paper proposes a “hybrid crowdsourcing” method that leverages the power of public crowd testers. This leads to generating a novel crowdtesting workflow Developer/Tester- Crowdtesting (DT-CT) that focuses on developers and crowd testers as key elements in the testing process without the need for intermediate as managers or leaders. This workflow has been used in a novel crowdtesting platform (AskCrowd2Test). This platform enables testing the compatibility of mobile devices and applications at two different levels, high-level (device characteristics) or low-level (code). Additionally, a “crowd-powered knowledge base” has been developed that stores testing results, relevant issues and their solutions.

The comparison of the presented DT-CT workflow with the common and most recent crowdtesting workflows showed that DT-CT may positively impact the testing process by reducing time-consuming and budget spend because of the direct interaction of developers and crowd testers.

To authors’ knowledge, this paper is the first to propose crowdtesting workflow based on developers and public crowd testers without crowd managers or leaders, which light the beacon for the future research in this field. Additionally, this work is the first that authorizes crowd testers with a limited level of experience to participate in the testing process, which helps in studying the behaviors and interaction of end-users with apps and obtains more concrete results.