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This study aims to address the limited understanding of the complex correlations among strut size, structural orientation and process parameters in selective laser melting (SLM)-fabricated lattice structures. By investigating the effects of crucial process parameters, strut diameter and angle on the microstructure and mechanical performance of AlSi10Mg struts, the research seeks to enhance the surface morphologies, microstructures and mechanical properties of AM lattice structures, enabling their application in various engineering fields, including medical science and space technologies.

This comprehensive study investigates SLM-fabricated AlSi10Mg strut structures, examining the effects of process parameters, strut diameter and angle on densification behavior and microstructural characteristics. By analyzing microstructure, geometrical properties, melt pool morphology and mechanical properties using optical microscopy, scanning electron microscope, energy dispersive X-ray spectroscopy and microhardness tests, the research addresses existing gaps in knowledge on fine lattice strut elements and their impact on surface morphology and microstructure.

The study revealed that laser energy, power density and strut inclination angle significantly impact the microstructure, geometrical properties and mechanical performance of SLM-produced AlSi10Mg struts. Findings insight enable the optimization of SLM process parameters to produce lattice structures with enhanced surface morphologies, microstructures and mechanical properties, paving the way for applications in medical science and space technologies.

This study uniquely investigates the effects of processing parameters, strut diameter and inclination angle on SLM-fabricated AlSi10Mg struts, focusing on fine lattice strut elements with diameters as small as 200 µm. Unlike existing literature, it delves into the complex correlations among strut size, structural orientation and process parameters to understand their impact on microstructure, geometrical imperfections and mechanical properties. The study provides novel insights that contribute to the optimization of SLM process parameters, moving beyond the typically recommended guidelines from powder or machine suppliers.

This study aims to evaluate the low energy impact characteristics of 3D printed carbon fiber thermoplastic and thermoset polymer composite using the Izod impact test. The effects of infill density are examined on the Izod impact properties of 3D printed thermoset polymer and thermoplastic composite specimens. Furthermore, a thorough investigation is conducted into the effect of heat treatment using a hot-air oven on both types of 3D printed composite specimens. To characterize the impact characteristics of each specimen, the fracture surfaces caused by impact load are inspected, and the fracture mechanism is studied using scanning electron micrographs.

Izod Impact specimens of thermoset (epoxy resin) and thermoplastic carbon fiber of different infill density (70, 75, 80, 85, 90 and 100%) are fabricated using the different fiber impregnation 3D printing process. To carry out the heat treatment process, printing of composites is done for each infill design from both thermoset and thermoplastic composites and the impact characteristics of specimens are evaluated on a pendulum test-rig using the ASTM D-256 standard. Using a scanning electron microscope, each fracture zone underwent four separate scanning processes, ranging in size from 2 µm to 100 µm.

The impact resistance of the 3D printed thermoset and thermoplastic composite material is significantly influenced by the type of fiber placement and infill density in the matrix substrate. Because of the weak interfacial strength between the layers of fiber and polyamide 6, the specimen printed with continuous fiber implanted at the part exhibited reduced impact resistance. At 75% infill density, the impact specimen printed with coextruded fiber showed the highest impact resistance with a 367.02% greater magnitude than the continuous fiber specimen with the same infill density.

This work presents a novel approach to analyze the low energy impact characteristics and three-dimensional printing of carbon fiber reinforced thermoplastic and carbon fiber reinforced thermoset and thermoplastic composite material.

Owing to the finite nature of the boundary of the line (BOL), the conventional method, involving the strong matching of single-variety parts with storage locations at the periphery of the line, proves insufficient for mixed-model assembly lines (MMAL). Consequently, this paper aims to introduce a material distribution scheduling problem considering the shared storage area (MDSPSSA). To address the inherent trade-off requirement of achieving both just-in-time efficiency and energy savings, a mathematical model is developed with the bi-objectives of minimizing line-side inventory and energy consumption.

A nondominated and multipopulation multiobjective grasshopper optimization algorithm (NM-MOGOA) is proposed to address the medium-to-large-scale problem associated with MDSPSSA. This algorithm combines elements from the grasshopper optimization algorithm and the nondominated sorting genetic algorithm-II. The multipopulation and coevolutionary strategy, chaotic mapping and two further optimization operators are used to enhance the overall solution quality.

Finally, the algorithm performance is evaluated by comparing NM-MOGOA with multi-objective grey wolf optimizer, multiobjective equilibrium optimizer and multi-objective atomic orbital search. The experimental findings substantiate the efficacy of NM-MOGOA, demonstrating its promise as a robust solution when confronted with the challenges posed by the MDSPSSA in MMALs.

The material distribution system devised in this paper takes into account the establishment of shared material storage areas between adjacent workstations. It permits the undifferentiated storage of various part types in fixed BOL areas. Concurrently, the innovative NM-MOGOA algorithm serves as the core of the system, supporting the formulation of scheduling plans.

This paper aims to explore global research on individuals’ awareness and behaviours related to the Circular Economy, aiming to deepen the understanding of how people engage with and contribute to CE practices.

Using a systematic literature review (SLR), this study methodically collects, codifies, analyses, synthesizes and interprets existing literature and research on Circular Economy. This approach aims for a comprehensive understanding of current global perspectives and practices.

The analysis reveals an increasing trend in empirical research focusing on Circular Economy strategies. This paper has identified 22 key strategies linked to public awareness and behaviours towards Circular Economy, noting that purchasing recycled products is the most commonly observed behaviour. The findings highlight the growing importance and complexity of individual roles in the Circular Economy.

The study underscores the importance of consumer behaviour in advancing Circular Economy practices. This paper observes that despite the growth in Circular Economy research, there is still a notable gap in awareness and behaviour, even in developed countries. This is attributed to a lack of conceptual understanding, educational disparities, resource limitations, a limited grasp of cost–benefit considerations and inadequate government support. The paper also explores regional and sector-specific variations in Circular Economy adoption, with insights from countries such as the USA, China, the UK, Germany, France and Norway.

This study underscores the importance of consumer behaviour in advancing Circular Economy practices. Despite the growth in Circular Economy research, there is still a notable gap in awareness and behaviour, even in developed countries. This is attributed to a lack of conceptual understanding, educational disparities, resource limitations, a limited grasp of cost–benefit considerations and inadequate government support. The paper also explores regional and sector-specific variations in Circular Economy adoption, with insights from countries such as the USA, China, the UK, Germany, France and Norway.

This research underscores the impact of demographic and sociocultural factors, including age, education, social norms and attitudes, on Circular Economy engagement. It identifies potential research areas, including examining cultural influences on social and personal norms related to circular behaviours. Ultimately, the study emphasizes the need for a coordinated, cross-sectoral effort to facilitate a sustainable transition to a Circular Economy, addressing barriers and fostering awareness and behaviours conducive to circular practices.

This study acknowledges challenges affecting the maturity of Circular Economy practices, including a lack of comprehension, educational disparities, resource constraints and limited government support. It also underscores the impact of social and cultural factors on Circular Economy engagement. It suggests promising avenues for future research, providing valuable insights into the state of Circular Economy practices and offering a roadmap for advancing global sustainability initiatives.

This chapter critically discusses the literature on the subject of circular economy. It defines the circular economy at the outset and advocates its adoption in smart cities. It briefly explains the multiple phases of industrial revolution and the slow and gradual shift from a linear economy which is based on make-use-dispose model to a circular economy which relies on reusing and recycling the products produced in the production cycle. It then critically examines the legal challenges that can be associated with such a system. It draws on the lessons learnt from cities such as Amsterdam which has successfully implemented the system of circular economy. This chapter also delves into the Columbian waste management system to understand the market functioning in the waste management sector which is handled by private enterprises in the country. Moreover, the public–private partnership model in the Chinese city Suzhou is explored, and exciting methods of using this model were found.

Arthroscopic osteochondroplasty is a minimally invasive procedure that has been used to treat femoroacetabular impingement syndrome, leading to significant improvements in patients’ clinical outcomes and quality of life. However, some studies suggest that inadequate bone resection can substantially alter hip biomechanics. These modifications may generate different contact profiles and higher contact forces, increasing the risk of developing premature joint degeneration. To improve control over bone resection and biomechanical outcomes during arthroscopic osteochondroplasty surgery, this study aims to present a novel system for measuring femoroacetabular contact forces.

Following a structured design process for the development of medical devices, the steps required for its production using additive manufacturing with material extrusion and easily accessible sensors are described. The system comprises two main devices, one for measuring femoroacetabular contact forces and the other for quantifying the force applied by the assistant surgeon during lower limb manipulation. The hip device was designed for use within an arthroscopic environment, eliminating the need for additional portals.

To evaluate its performance, the system was first tested in a laboratory setup and later under in-service conditions. The 3D printing parameters were tuned to ensure the watertighness of the device and sustain the intraoperative fluid pressures. The final prototype allowed for the controlled measurement of the hip contact forces in real-time.

Using additive manufacturing and readily available sensors, the present work presents the first device to quantify joint contact forces during arthroscopic surgeries, serving as an additional tool to support the surgeon’s decision-making process regarding bone resection.

This paper aims to propose a methodology for assessing an optimal portfolio of investment instruments that minimise the social costs of decarbonising economic activity while improving the environmental objectives proposed in EU legislation.

The methodology defines the net social cost of decarbonisation related to a portfolio of four instruments: installation of solar PV and wind generation, thermal insulation of households and deployment of heat pumps. The social cost is minimised by restricting it to the minimum level of the targets proposed in the Spanish National Energy and Climate Plan to reduce greenhouse gas emissions, increase generation from renewable sources and reduce energy consumption. The empirical approach also includes differences between regions according to the expected effect for instruments.

The application of this methodology to the environmental objectives defined in the current Spanish National Energy and Climate Plan for 2030 concludes that it is clearly possible to reduce the social cost of decarbonisation while improving environmental performance through a reorientation of investment instruments. In this case, such a reorientation would be based on a minimisation of efforts in thermal insulation of households and a maximisation of measures aimed at the installation of heat pumps.

The paper proposes a novel methodology for a social cost assessment that improves the allocation of a portfolio of environmental instruments. This portfolio could be extended in further work to include instruments related to transport or support for industrial decarbonisation, such as the deployment of renewable hydrogen, among others.

Stakeholder interests are complex, sensitive and highly uncertain and may influence the development of net zero carbon building (NZCB). However, this study aims to conduct a systematic literature review to explore the stakeholder interests towards achieving NZCB.

A total of 62 articles were identified from the Scopus database and thoroughly reviewed to extract relevant information on stakeholders' interest towards achieving NZCB.

A total of 28 stakeholder interests influencing the development of NZCB were identified from the literature and were classified into six major groups according to their uniqueness (economic, social, environmental, technological, political, regulatory and legal).

The findings of this study provide insight into the specific stakeholder interests towards achieving NZCB. Thus, the findings of this study could serve as a guide for future research, policy formulation and implementation to expedite the practice of building towards net zero carbon (NZC). Empirical studies are suggested in future studies to test and consolidate the theoretical claims of this study.

This paper undertakes a comprehensive systematic review of studies on stakeholder interests towards achieving NZCB, which is the least investigated in the literature.

This study aims to examine the adoption of Metaverse technology in the manufacturing industry and its potential impact on firms’ social and environmental sustainability performance.

Data were collected from 157 technology-based firms in the Malaysian high-tech manufacturing industry and analyzed using PLS-SEM to investigate the influence of social (i.e. social capital, open/innovative culture and empowerment) and technological factors (i.e. digitalization preparedness, integrability and strategic value) on Metaverse adoption and the moderating roles of digital trust and absorptive capacity.

Social and technological factors were found to significantly impact Metaverse adoption, with digital trust enhancing the influence of social factors. Absorptive capacity strengthens firms’ abilities to use social factors for adoption. However, digital trust does not significantly moderate the relationship between technological factors and adoption, nor does absorptive capacity impact this relationship. Finally, Metaverse adoption is shown to positively contribute to firms’ social sustainability, improving social well-being and equity, but it does not significantly impact environmental sustainability.

For practitioners, the study highlights the importance of fostering an organizational culture that supports digital trust and developing absorptive capacity as critical enablers of successful Metaverse adoption. Policy implications include the need for creating supportive policies that encourage digital transformation efforts aligned with sustainability goals.

Theoretically, this study integrates the Technology-Organization-Environment (TOE) framework, Human-Organization-Technology fit (HOT-fit) framework and Resource-Based View (RBV) to improve understanding of technology adoption and sustainability performance. From a managerial perspective, it highlights the importance of fostering digital trust and developing absorptive capacity as critical enablers of successful Metaverse adoption. Policy implications include the need for policies supporting digital transformation efforts aligned with sustainability goals.

The pharmaceutical industry is facing significant pressure to tackle antimicrobial resistance (AMR). Other ecological, societal and regulatory pressures are also driving the industry to “go green”. While such a (green) transition could be possible through appropriate green practices’ implementation, the present understanding about it is superficial and vague. A key reason is the lack of green practices’-related studies on pharmaceuticals, which are also insufficiently comprehensive. This knowledge gap is sought to be addressed.

A systematic literature review (SLR) was conducted with 73 carefully selected articles, then subjected to thematic content analyses for synthesising the relevant themes and sub-themes.

Around 76 operational-level green practices covering all key stakeholders across the drug lifecycle were identified. It was revealed that designing drugs having accelerated environmental degradability is important to combat AMR. Also, redesigning existing drugs is environmentally more resource-intensive than developing new ones with significant cost-saving potential in solvent recycling and flexible manufacturing, both of which are not common at present. With regards to green-related barriers, stringent quality requirements on drugs (and therefore risks in making relevant green-oriented modifications) and time-consuming and costly regulatory approvals were found to be the key ones.

The operational green practices’ framework developed for individual pharmaceutical supply chain stakeholders could help practitioners in benchmarking, modifying and ultimately, adopting green practices. The findings could also assist policymakers in reframing existing regulations, such as Good Manufacturing Practices or GMP-related, to promote greener drug development.

This work is the first systematic attempt to identify and categorise operational-level green supply chain practices across stakeholders in the pharmaceutical sector.

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  Biodegradability of drugs is more important than environmental degradability.

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  Flexible manufacturing process design (or quality by design) reduces resource wastage.

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  Ecopharmacovigilance is effective in combating PIE and AMR-related issues.

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  Upstream and downstream coordination is key to greening pharma operations.

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  Costly and time-consuming regulatory approval is a key barrier to greening pharma processes.

Biodegradability of drugs is more important than environmental degradability.

Flexible manufacturing process design (or quality by design) reduces resource wastage.

Ecopharmacovigilance is effective in combating PIE and AMR-related issues.

Upstream and downstream coordination is key to greening pharma operations.

Costly and time-consuming regulatory approval is a key barrier to greening pharma processes.