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This study aims to investigate the impact of varying the number of minimum quantity lubrication (MQL) nozzles, wind pressure, spindle speed and type of lubrication on surface roughness, fatigue life and tool wear in the drilling of aluminum alloy 6061-T6.

The effect of using different lubricants such as palm oil, graphene/water nanofluid and SiO₂/water in the MQL method was compared with flood and dry methods. The lubricant flow and feed rate were kept constant throughout the drilling, while the number of nozzles, wind pressure and spindle speed varied. After preparing the parts, surface roughness, fatigue life and tool wear were measured, and the results were analyzed by ANOVA.

The results showed that using MQL with four nozzles and graphene/water nanofluid reduced surface roughness by 60%, followed by SiO₂ nanofluid at 56%, and then by palm oil at 50%. Increasing the spindle speed in MQL mode with four nozzles using graphene nanofluid decreased surface roughness by 52% and improved fatigue life by 34% compared to the dry mode. SEM results showed that tool wear and deformation rates significantly decreased. Increasing the number of nozzles caused the fluid particles to penetrate the cutting area, resulting in improved tool cooling with lubrication in all directions.

Numerous attempts have been made worldwide to eliminate industrial lubricants due to environmental pollution. In this research, using nanofluid with wind pressure in MQL reduces environmental impacts and production costs while improving the quality of the final workpiece more than flood and dry methods.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0021/

Additive manufacturing (AM), also known as three-dimensional (3D) printing technology, has been used in the health-care industry for over two decades. It is in high demand in the health-care industry due to its strength to manufacture custom-designed and personalized 3D constructs. Recently, AM technologies are being explored to develop personalized drug delivery systems, such as personalized oral dosages, implants and others due to their potential to design and develop systems with complex geometry and programmed controlled release profile. Furthermore, in 2015, the US Food and Drug Administration approved the first AM medication, Spritam® (Apprecia Pharmaceuticals) which has led to tremendous interest in exploring this technology as a bespoke solution for patient-specific drug delivery systems. The purpose of this study is to provide a comprehensive overview of AM technologies applied to the development of personalized drug delivery systems, including an analysis of the commercial status of AM based drugs and delivery devices.

This review paper provides a detailed understanding of how AM technologies are used to develop personalized drug delivery systems. Different AM technologies and how these technologies can be chosen for a specific drug delivery system are discussed. Different types of materials used to manufacture personalized drug delivery systems are also discussed here. Furthermore, recent preclinical and clinical trials are discussed. The challenges and future perceptions of personalized medicine and the clinical use of these systems are also discussed.

Substantial works are ongoing to develop personalized medicine using AM technologies. Understanding the regulatory requirements is needed to establish this area as a point-of-care solution for patients. Furthermore, scientists, engineers and regulatory agencies need to work closely to successfully translate the research efforts to clinics.

This review paper highlights the recent efforts of AM-based technologies in the field of personalized drug delivery systems with an insight into the possible future direction.

This paper aims to investigate the effect of chemical nickel plating and mechanical alloying on the mechanical and tribological properties of FeS/iron-based self-lubricating materials as well as the wear mechanism of the materials.

Surface modification of FeS powder was carried out by chemical nickel plating method and mechanical alloying of mixed powder by ball milling. The mechanical properties of the material were tested by tribological testing by M-200 ring block type friction and wear tester. Optical microscope was used to observe the surface morphology of the material and the transfer film on the surface of the mate parts, and scanning electron microscope and EDS were used to characterize the wear surface.

Mechanical alloying ball milling was carried out so that the lubricating particles in the matrix are uniformly dispersed; nickel-plated layer enhances the interfacial bonding of FeS and the matrix, and the combination of the two improves the mechanical properties of the material, and at the same time the friction side of the surface of the lubrication of FeS lubricant transfer film formed is denser and more intact, and the friction coefficient of friction side and the wear rate of the material have been greatly reduced.

This work aims to improve the mechanical and tribological properties of FeS/iron-based self-lubricating materials and to provide a reference for the preparation of materials with excellent overall properties.

After completion of the case study, students will be able to understand the format of for-profit social enterprise working for menstrual hygiene sustainability and its contribution toward U.N. Sustainable Development Goals, to appreciate the company’s alignment with the triple bottom line framework, to analyze the blue ocean mechanism that the company has developed to create an impact and to critique the strategies the Asan Cups company could adopt to increase its market share and growth.

Asan Cups was a for-profit social enterprise founded by Ira Guha in 2021. The company crafted reusable menstrual cups from liquid silicone, sporting a patented design in India, the UK, Europe and the USA. Successfully retailing its products in India, the UK and Europe, Asan Cups operated on a bootstrap model with a compact team of four, led by its visionary founder. From the get-go, the company embraced a compelling 1-for-1 donation initiative. For every cup sold, Asan Cups generously donated another to women who could not afford it. Collaborating with nongovernmental organizations, schools, educational institutions and social workers, the company spearheaded campaigns to heighten menstrual hygiene awareness. This proactive approach aimed to boost the acceptance of menstrual cups among rural women and championed the cause of environmental sustainability. The company did not just stop at providing an eco-friendly alternative. Asan Cups fervently educated the masses on the detrimental environmental impact of traditional disposable period products like sanitary pads and tampons. Fast-forwarding to 2023, Asan Cups had garnered approximately 30,000 users, with the adoption rate steadily climbing. The company strategically used an education-intensive model to foster awareness about period products in collaboration with partners nationwide. However, being a for-profit entity, the founder, Guha, was at a crossroads. Balancing the need for profitability, there was mounting pressure to explore additional revenue streams and expand operations and market reach. The dilemma loomed large: opt for a quicker marketing strategy or stay true to the company’s foundational education-centered approach. This case study delves into the dynamic strategies, impactful operations and growth scenarios Asan Cups navigated since its inception. It examines the pivotal choices faced by the founder and explores potential strategies for sustained growth.

This case study can be used at both undergraduate and master’s levels. The case study will be handy for strategic management and business strategy courses and can also be used for social entrepreneurship, marketing and entrepreneurship courses.

Teaching notes are available for educators only.

CSS 11: Strategy.

This research assesses the present condition of Circular Economy (CE) practices in green hotels situated in two leading Middle Eastern nations, Saudi Arabia and Egypt. Furthermore, it investigates the crucial impact of Industry 4.0 innovations in facilitating the relationship between the adoption of CE initiatives and hotel performance (HP).

Data from 59 green hotels in Saudi Arabia and 76 in Egypt were collected online, resulting in 400 complete forms, providing a diverse sample size suitable for PLS-SEM analysis using JASP software as a leading machine learning application.

The results demonstrate a notable correlation between CE strategies, including redesign, production, reuse and recovery in hotels and HP. Additionally, the impact of Industry 4.0 performance on the relationship between CE and HP is facilitated by four distinct CE loops.

This study offers practical insights into implementing CE practices in the hotel industry, aiding policymakers and establishments in enhancing sustainability and performance. Key stakeholders can use these findings to develop strategies that integrate CE initiatives, improve operational outcomes and align marketing efforts with sustainable practices.

This study is groundbreaking in its exploration of the relationship between CE and the transition to Industry 4.0 in the MENA region, analyzing the specific CE practices that contribute to high HP. The tested model expands on the Natural Resource-Based View and stakeholder theory by incorporating the critical role of Industry 4.0 innovations in the CE–HP nexus.

This study aims to investigate the demoulding characteristics of material-jetted rapid mould inserts having different surface textures for micro-injection moulding using in-line measurements and surface metrology.

Material-jetted inserts with the negative cavity of a circular test product were fabricated using different surface finishes and printing configurations, including glossy, matte and vertical settings. In-line measurements included the recording of demoulding forces at 10 kHz, which was necessary to capture the highly-dynamic characteristics. A robust data processing algorithm was used to extract reliable demoulding energies per moulding run. Thermal imaging captured surface temperatures on the inserts after demoulding. Off-line measurements, including focus variation microscopy and scanning electron microscopy, compared surface textures after a total of 60 moulding runs.

A framework for capturing demoulding energies from material-jetted rapid tools was demonstrated and compared to the literature. Glossy surfaces resulted in significantly reduced demoulding forces compared to the industry standard steel moulds in the literature and their material-jetted counterparts. Minimal changes in the surface textures of the material-jetted inserts were found, which could potentially permit their prolonged usage. Significant correlations between surface temperatures and demoulding energies were demonstrated.

The research presented here addresses the very topical issue of demoulding characteristics of soft, rapid tools, which affect the quality of prototyped products and tool durability. This was done using state-of-the-art, high-speed sensing technologies in conjunction with surface metrology and their durability for the first time in the literature.

This study aims to understand the influence of raceway surface topography on the temperature rise characteristics of silicon nitride (Si₃N₄) full ceramic ball bearing and improve its service life.

The arithmetic average height S_a, skewness S_sk and kurtosis S_ku in the three-dimensional surface roughness parameters are used to quantitatively characterize the surface topography of the raceway after superfinishing. The bearing life testing machine is used to test the Si₃N₄ full ceramic ball bearing using polytetrafluoroethylene (PTFE) cage under dry friction conditions, and the self-lubricating full ceramic ball bearing heat generation model is established.

With the decrease of S_a and S_sk on the raceway surface and the increase of S_ku, the average height of the raceway surface decreases, and the peaks and valleys tend to be symmetrically distributed on the average surface, and the surface texture becomes tighter. This kind of raceway surface topography is beneficial to form a thin and uniform filamentous PTFE transfer film with a wide coverage area on the raceway surface based on consuming less cage materials and improving the temperature rise characteristics of hot isostatic pressing silicon nitride full ceramic ball bearings.

The research results provide a theoretical basis for the reasonable selection of Si₃N₄ ring raceway processing technology and have important significance for improving the working characteristics and service life of Si₃N₄ full ceramic ball bearings under dry friction conditions.