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Presently in multicolor fused filament-based three-dimensional (3-D) printing, significant amounts of waste material are produced through nozzle priming and purging each time a change from one color to another occurs. G-code generating slicing software typically changes the material on each layer resulting in wipe towers with greater mass than the target object. The purpose of this study is to provide an alternative fabrication approach based on interlayer tool clustering (ITC) for the first time, which reduces the number of tool changes and is compatible with any commercial 3-D printer without the need for hardware modifications.

The authors have developed an open-source PrusaSlicer upgrade, compatible with Slic3r-based software, which uses the described algorithm to generate g-code toolpath and print experimental objects. The theoretical time, material and energy savings are calculated and validated to evaluate the proposed fabrication method qualitatively and quantitatively.

The experimental results show the novel ITC method can significantly increase the efficiency of multimaterial printing, with an average 1.7-fold reduction in material use, and an average 1.4-fold reduction in both time and 3-D printing energy use. In addition, this approach reduces the likelihood of technical failures in the manufacturing of the entire part by reducing the number of tool changes, or material transitions, on average by 2.4 times.

The obtained results support distributed recycling and additive manufacturing, which has both environmental and economic benefits and increasing the number of colors in a 3-D print increases manufacturing savings.

Wool fiber is accepted as one of the natural and renewable sources and has been used in the apparel and textile industry since ancient times. However, wool fiber has the highest global warming potential value among conventional fibres due to its high land use and high methane gas generation. This study aimed to recycle the wool fabric wastes and also to create a mini eco-collection by using the produced yarns.

This manuscript aimed to evaluate the fabric wastes of a woolen fabric producer company. Fabric wastes were opened with two different opening systems and fiber properties were determined. First, conventional ring yarns were produced in the company’s own spinning mill by mixing the opened fibres with the long fiber wastes of the company. In addition, opening wastes were mixed with different fibres (polyester, long wool waste, and Tencel fibres) between 25% and 70% in the short-staple yarn spinning mill and used in the production of conventional ring and OE-rotor yarns. Most of the yarns contained waste fibres at 50%. Recycled and virgin yarns were used as a weft and warp yarn and a total of 270 woven fabric samples were obtained and fabric properties were examined. Also, a fabric collection was created. A life cycle assessment (LCA) was made for one of the selected yarns.

At the end of the study, it was determined that it was possible to produce yarn and fabric samples from fiber blends containing high waste fiber ratios beyond 50%. All the woven fabric samples produced from conventional ring and OE-rotor yarns gave higher breaking, tearing and stitch slip strength values in the weft and warp direction than limit quality values of the company. In addition, abrasion resistance and WIRA steam stability properties of the fabric samples were also sufficient. Environmental analysis of the recycling of the wastes showed a possible decrease of about 9940034.3 kg CO2e per year in the global warming potential. In addition, fiber raw material expenses reduced yarn production cost about 50% in case of opened fabric waste usage. However, due to insufficient pilling resistance results, it was decided to evaluate the woven fabrics for the product groups such as shawls and blankets, where pilling resistance is less sought.

The original aspects of the article can be summarized under two headings. First, there are limited studies on the evaluation of wool wastes compared to cotton and polyester fibres and the number of samples examined was limited. However, this study was quite comprehensive in terms of opening type (rag and tearing), spinning systems (long and short spinning processes), fiber blends (waste 100% and blends with polyester, long wool waste and Tencel fibres) and yarn counts (coarser and finer). Recycled and virgin yarns were used as a weft and warp yarn and a total of 270 woven fabric samples were obtained using different colour combinations and weave types. All processes from fabric waste to product production were followed and evaluated. Life cycle assessment (LCA) and cost analysis was also done. The second unique aspect is that the problem of a real wool company was handled by taking the waste of the woolen company and a collection was created for the customer group of the company. Production was made under real production conditions. Therefore, this study will provide important findings to the research field about recycling, sustainability etc.

Civic education in the US has historically centered the nation-state. This is often disempowering for marginalized students who exist outside the national narrative and political sphere.

This year-long ethnographic study considers what counts as civic education in the US Virgin Islands, a territory of the US. This paper draws on critical theory and critical pedagogy to understand ways teachers in a politically and culturally marginalized space can reimagine civic education. Classroom observations, interviews and curriculum content analysis are used as data.

The findings suggest that teachers centered the local by surfacing the unjust political relationship between the US and its territories and incorporating local history, civic engagement, resistance and culture to politically empower their students.

This research will contribute a deeper understanding of the possibilities for civic education to be empowering for those who are marginalized and often excluded from the national political arena.

The current study aims to develop a 3D-printed continuous metal fiber-reinforced recycled thermoplastic composite using an in-nozzle impregnation technique.

Recycled acrylonitrile butadiene styrene (RABS) plastic was blended with virgin ABS (VABS) plastic in a ratio of 60:40 weight proportion to develop a 3D printing filament that was used as a matrix material, while post-used continuous brass wire (CBW) was used as a reinforcement. 3D printing was done by using a self-customized print head to fabricate the flexural, compression and interlaminar shear stress (ILSS) test samples to evaluate the bending, compressive and ILSS properties of the build samples and compared with VABS and RABS-B samples. Moreover, the physical properties of the samples were also analyzed.

Upon three-point bend, compression and ILSS testing, it was found that RABS-B/CBW composite 3D printed with 0.7 mm layer width exhibited a notable improvement in maximum flexural load (L_max), flexural stress at maximum load (sf_max), flex modulus (E_f) and work of fracture (WOF), compression modulus (E_c) and ILSS properties by 30.5%, 49.6%, 88.4% 13.8, 21.6% and 30.3% respectively.

Limited research has been conducted on the in-nozzle impregnation technique for 3D printing metal fiber-reinforced recycled thermoplastic composites. Adopting this method holds the potential to create durable and high-strength sustainable composites suitable for engineering applications, thereby diminishing dependence on virgin materials.

Intumescent coatings are nowadays a dominant passive system used to protect structural materials in case of fire. Due to their reactive swelling behaviour, intumescent coatings are particularly complex materials to be modelled and predicted, which can be extremely useful especially for performance-based fire safety designs. In addition, many parameters influence their performance, and this challenges the definition and quantification of their material properties. Several approaches and models of various complexities are proposed in the literature, and they are reviewed and analysed in a critical literature review.

Analytical, finite-difference and finite-element methods for modelling intumescent coatings are compared, followed by the definition and quantification of the main physical, thermal, and optical properties of intumescent coatings: swelled thickness, thermal conductivity and resistance, density, specific heat capacity, and emissivity/absorptivity.

The study highlights the scarce consideration of key influencing factors on the material properties, and the tendency to simplify the problem into effective thermo-physical properties, such as effective thermal conductivity. As a conclusion, the literature review underlines the lack of homogenisation of modelling approaches and material properties, as well as the need for a universal modelling method that can generally simulate the performance of intumescent coatings, combine the large amount of published experimental data, and reliably produce fire-safe performance-based designs.

Due to their limited applicability, high complexity and little comparability, the presented literature review does not focus on analysing and comparing different multi-component models, constituted of many model-specific input parameters. On the contrary, the presented literature review compares various approaches, models and thermo-physical properties which primarily focusses on solving the heat transfer problem through swelling intumescent systems.

The presented literature review analyses and discusses the various modelling approaches to describe and predict the behaviour of swelling intumescent coatings as fire protection for structural materials. Due to the vast variety of available commercial products and potential testing conditions, these data are rarely compared and combined to achieve an overall understanding on the response of intumescent coatings as fire protection measure. The study highlights the lack of information and homogenisation of various modelling approaches, and it underlines the research needs about several aspects related to the intumescent coating behaviour modelling, also providing some useful suggestions for future studies.

Social disclosure is a vital tool that can help organizations in developing economies, including Nigeria, measure and manage their social impacts and performances. This could help in achieving sustainable development goals and enhancing social and economic security. This paper aims to conceptualize the influence of social reporting and sustainable development on Nigeria’s socioeconomic security. It is vital for its recommendations to the government and stakeholders on the way forward on sustainable development and national security.

A dissection through content analyses using the frustration-aggression and social contract theories was made on the influence of voluntary social reporting and sustainable development on socioeconomic security in Nigeria. An examination and assessment of the implementation of social disclosure by organizations and its effectiveness in promoting sustainable development with insights into the challenges and opportunities in a developing economy like the Nigerian context was done.

The results showed an increasingly negative trend in social and economic circles brought about by business organizations’ nonmandatory disclosure of social and environmental information. Therefore, it is suggested that governments should have a strong will to implement mandatory reporting to avoid future political catastrophes.

Implications emerged from this study inform policymakers, businesses and other stakeholders on the ways to enhance mandatory social sustainability in Nigeria.

This report is unique in the sense that it considers the interplay between sustainable development and socioeconomic security moderated by voluntary social disclosure as a virgin area in studies that involve developing economies.

The COVID-19 pandemic has caused irrefutable devastation globally. Yet, academic and trade commentators have claimed that this disruption could have had a silver lining by presenting the fashion industry with the opportunity to reassess and rebuild in a slower, more considered way. Part of this reassessment, some have argued, may have been allowing the industry's pre-COVID sustainability buzz to come to fruition by nudging the fashion industry to go circular. This paper explores if, and how, the COVID-19 pandemic was (not) nudging the industry towards circularity using the case study of circular textiles.

Serial, semi-structured, qualitative interviews were conducted with three buyers and sourcers working for three UK-based fashion retailers. Each participant was involved in three interviews in June 2020 following the UK's first national lockdown.

The research findings suggest that, at the time this research was undertaken, these retailers were focussed on regaining profit, protecting their supply chains and producing “safe” designs whilst cutting back and becoming more risk averse. These actors suggested that, in contrast to the suppositions made by academic and media commentators, the COVID-19 pandemic was acting as a hindrance to circularity, not a helping hand, as retailers were less willing to invest in circular textiles at that time than they were pre-pandemic.

This paper offers valuable insight into the COVID-19 pandemic's impact on circular innovation within fashion retail whilst contributing to broader understandings of the principles of the circular economy within textiles and design.

The case is derived from secondary sources, including publicly available reports and information about all companies directly or indirectly engaged in the industry. No primary sources were available.

This teaching case is designed for students to demonstrate their mastery of industry-level analysis in the emerging space tourism industry. It allows students to understand what constitutes the industry within the broader space sector and to apply analytical tools such as PESTEL and Porter’s Five Forces, with the option to discuss strategic groups. Students gain insights into how the industry is evolving within its broader environment and how companies could respond or differentiate themselves. Information is also provided for students to consider the broader social impact of a relatively new industry from the perspective of sustainable development.

The case is written for undergraduate and graduate students enrolled in strategic management courses. The case placement is ideally in conjunction with industry-level analytical frameworks such as Porter’s Five Forces, PESTEL analysis, strategic groups (optional) and industry life cycle. Most strategic management textbooks cover these concepts in the first few chapters. For example, “Strategic Management, 14th edition” by Hill, Schilling and Jones (2023) covers these topics in chapter 2. Given that space tourism is an embryonic industry dependent on technological innovation, instructors might also use this case in innovation or entrepreneurship-related courses. This case could also be used to address critical issues, such as sustainability, in tourism management courses.

The purpose of this study is to provide quantitative information about the development of Islamic financial management literature. For this purpose, it is aimed to draw attention to the development of this field by revealing the literature gap in the field of Islamic financial management.

In this study, the document analysis method is used and the Web of Science (WOS) site is used to obtain the desired data. The time range of the study covers the years 1980–2023/January. The results obtained from the scans were analyzed by the bibliometric analysis method. The data obtained within the scope of the study are classified and analyzed using the VOSviewer program, which is one of the many software developed for scientific mapping analysis. The obtained data are presented in a certain order with the visual mapping method.

In the analyses made, bibliometric analysis based on document review and including the subject of “Islamic financial management” in the WOS database between the relevant years has not been used in any study, which points to an important gap in the literature. However, 3,022 studies on “Financial management” and 1,830 studies on “Islamic finance” have been identified. Although there is no data on “Financial Management”, the subjects of “Islamic finance” and “Financial management” related to the subject have been evaluated in terms of countries, the most publishing organizations, authors, publications and word–word groups, using the bibliometric analysis method, as well as making numerical and visual evaluations. These studies show that an infrastructure to include the subject of “Islamic financial management” has not been formed in the literature.

This study points to an important gap in the literature. The subjects of “Islamic finance” and “Financial management” have been sufficiently covered in the literature separately. By combining this knowledge with new studies there appears an environment where original studies on the subject of “Islamic financial management” can be made and this study is aimed to shed light on this virgin area.

In the literature bibliometric analysis based on document review including the subject of “Islamic financial management” has not been used in any study. To the best of the author’s knowledge this study is the first in the literature to address the related issue and with it an important gap in the literature has been identified and an important case that will be a source for future studies has been revealed.

Societal response to COVID induced many changes in the way we now live. Air transportation was one of the more visible “victims” of COVID response, with several major airlines declaring bankruptcy and others downsizing to a degree not seen previously. In spite of these shocks, the international air cargo sector carried on. Anecdotal evidence suggests airlines that either specialized in cargo or in turn were able to adjust their fleets to carry more cargo (including better utilization of existing backhauls) were best able to weather the pandemic. To explore this issue further, we examine detailed international air passenger and cargo traffic data (both fronthaul and backhaul) from the US Bureau of Transportation Statistic's TranStats database before and during COVID to elucidate how the pandemic affected air carrier operations at a time of great uncertainty. Better operational flexibility seems to have been critical to success during COVID. To this end, we find that many Asian-based carriers were superior at adjusting to the new cargo refocused reality of COVID operations, while their US-based counterparts lagged substantially behind. We speculate on potential reasons for this difference and also what our findings might mean for industry investment moving forward.