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The purpose of this paper is to improve the seal performance by proper design of the cavity shape of the damping holes, especially the rotordynamics characteristics of the hole-pattern damped seal (HPDS).

A new damping seal structure that comprises a circle-shaped cavity and two directional leaf-shaped cavities with a dovetail-shaped diversion groove is proposed. The comparative study on the sealing characteristics of dovetail-shape, leaf-shape and classical circular HPDSs was carried out using ANSYS CFX.

The dovetail-shaped HPDS significantly outperformed two other damping seal designs in leakage and rotordynamic performance. At a rotating speed of 7,500 rpm, it showed a 25% reduction in leakage, a 23% increase in average effective damping and a 119% increase in average effective stiffness. The cross-coupled stiffness K_xy shifted from positive to negative, reducing circumferential flow. The dovetail's inclined leaf-shaped grooves create a double vortex that slows jet velocity in the seal clearance and alters spiral flow direction, resulting in a uniform pressure distribution and enhanced rotor stability at low frequencies.

This study proposes a novel HPDS with dovetail-shaped diversion grooves. The seal can realize the simultaneous improvement of rotordynamics and leakage characteristics compared to the current seal structure.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0127/

Access to education has been globalized and democratized to a certain extent through massive open online courses (MOOCs) and other open-access platforms and content databases. In a recent study by Inayatullah and Milojević (2014), the recommendations were to establish a pilot project, enhance digital pedagogy and learning, customize degrees, create a culture of change in higher education, enhance collaboration, support research activities, redefine frames of reference, and anticipate and prepare for futures trends. The need for democratization of education has been increasing to meet the need of individuals and groups to assert and highlight their identity and role in society. Education is the means to facilitate this through a practical and active approach through wider stakeholder participation. Religious belief was identified as the main cause of conflicts among multi-ethnic cohorts. Adding socio-cultural differences to the mix and uncontrolled access to various opinions through social media makes the task much more complex. Educational policies must consider mother-tongue learning to improve learning outcomes. However, making the vast learning content accessible in multiple languages could be daunting. This chapter explores these emerging challenges and changing stakeholder expectations from the formal education system. The policy implications, possible technology-driven solutions, and their effectiveness in addressing the growing challenges of a global learning village have been explored.

Metaverse is going to change the landscape in every field, sector, and business. This chapter aims to explore the role of marketing in the metaverse focusing on each sector and business. This chapter has adopted bibliometrics analysis to explore the importance of metaverse marketing. The results suggest that the publication and citation of articles have seen a huge jump from 2022 onwards. Keyword co-occurrence analysis shows that metaverse with blockchain, marketing, education, and virtual reality (VR) are hot words in the upcoming time. Metaverse marketing shows that innovation, mixed reality, and extended reality will change the landscape of marketing. Analysis suggests that China, the United States, South Korea, and India are the top contributing countries in the research of metaverse. By understanding the implications of the metaverse on purchaser conduct and promoting systems, organizations can draw in the main interest group and gain esteem in this new advanced scene.

The aim of this paper is to study the effect of laser shock peening (LSP) on mechanical behaviour of the laser-directed energy deposition (LDED)-based printed 15-5 PH stainless steel with U and V notches. The study specifically concentrates on the evaluation of effect of scan strategy, machining and LSP processing on microstructural, texture evolution and fatigue behaviour of LDED-printed 15-5 PH steel.

For LSP treatment, 15-5 PH steel was printed using LDED process with bidirectional scanning strategy (XX [θ = 0°) and XY [θ = 90°]) at optimised laser power of 600 W with a scanning speed of 300 mm/min and a powder feed rate of 3 g/min. Furthermore, LSP treatment was conducted on the V- and U-notched fatigue specimens extracted from LDED-built samples at laser energy of 3.5 J with a pulse width of 10 ns using laser spot diameter of 3 mm. Post to the LSP treatment, the surface roughness, fatigue life assessment and microstructural evolution analysis is performed. For this, different advanced characterisation techniques are used, such as scanning electron microscopy attached with electron backscatter diffraction for microstructure and texture, X-ray diffraction for residual stress (RS) and structure information, Vicker’s hardness tester for microhardness and universal testing machine for low-cycle fatigue.

It is observed that both scanning strategies during the LDED printing of 15-5 PH steel and laser peening have played significant role in fatigue life. Specimens with the XY printing strategy shows higher fatigue life as compared to XX with both U- and V-notched conditions. Furthermore, machining and LSP treatment led to a significant improvement of fatigue life for both scanning strategies with U and V notches. The extent of increase in fatigue life for both XX and XY scanning strategy with V notch is found to be higher than U notch after LSP treatment, though without LSP samples with U notch have a higher fatigue life. As fabricated sample is found to have the lowest fatigue life as compared to machines and laser peened with both scan strategies.

This study presents an innovative method to improve the fatigue life of 15-5 PH stainless steel by changing the microstructure, texture and RS with the adoption of a suitable scanning strategy, machining and LSP treatment as post-processing. The combination of preferred microstructure and compressive RS in LDED-printed 15-5 PH stainless steel achieved with a synergy between microstructure and RS, which is responsible to improve the fatigue life. This can be adopted for the futuristic application of LDED-printed 15-5 PH stainless steel for different applications in aerospace and other industries.

The purpose of this study is to identify the causative factors of metro construction safety accidents, analyze the correlation between accidents and causative factors and assist in developing safety management strategies for improving safety performance in the context of the Chinese construction industry.

To achieve these objectives, 13 types and 48 causations were determined based on 274 construction safety accidents in China. Then, 204 cause-and-effect relationships among accidents and causations were identified based on data mining. Next, network theory was employed to develop and analyze the metro construction accident causation network (MCACN).

The topological characteristics of MCACN were obtained, it is both a small-world network and a scale-free network. Controlling critical causative factors can effectively control the occurrence of metro construction accidents. Degree centrality strategy is better than closeness centrality strategy and betweenness centrality strategy.

In practice, it is very difficult to quantitatively identify and determine the importance of different accidents and causative factors. The weights of nodes and edges are failed to be assigned when constructing MCACN.

This study provides a theoretical basis and feasible management reference for construction enterprises in China to control construction risks and reduce safety accidents. More safety resources should be allocated to control critical risks. It is recommended that safety managers implement degree centrality strategy when making safety-related decisions.

This paper establishes the MCACN model based on data mining and network theory, identifies the properties and clarifies the mechanism of metro construction accidents and causations.

This study aims to identify the intermediate psychological mechanism – organizational identification – that links authentic leadership with follower’s organizational citizenship behavior (OCB). Moreover, it examines the moderating role of perceived organizational support (POS) in the relationship between authentic leadership and organizational identification.

This study uses a cross-sectional research design involving 356 employees from diverse corporations in South Korea. Data were collected using a structured questionnaire to measure perception of authentic leadership, organizational identification, POS and OCB.

The results indicate that organizational identification significantly mediates the relationship between the perception of authentic leadership and follower’s OCB. Furthermore, POS acts as a moderating variable, strengthening the relationship between authentic leadership and organizational identification. Specifically, followers who perceive strong support from their organization are more likely to develop a robust sense of organizational identification under authentic leadership, which in turn, enhances their OCB.

This study offers a novel integration of social identity theory and organizational support theory to examine how authentic leadership influences follower’s OCB. It is among the first to introduce organizational identification as an intermediary in this context and to investigate the moderating effect of POS. The findings provide valuable insights for managers aiming to cultivate a workplace culture that fosters organizational identification and citizenship behaviors, thereby enhancing organizational effectiveness. Future research directions are also highlighted.

The study aims to explore how fashion visual symbols influence consumers' inclination for repurchasing. It attempts to investigate the intricate interplay among three essential variables (social presence, collective excitement and cultural identification) from the perspective of Interaction Ritual Chains theory. Meanwhile, an attempt is made to reveal the underlying patterns in these relationships, fully harnessing the positive impact of fashion brand visual symbols in brand marketing.

This study employs a quantitative research methodology, administering an online survey in China, from which 381 valid responses were collected by simple random sampling. The acquired data were subjected to structural equation model and hypotheses testing.

The analysis reveals that heightened visual symbol perception significantly strengthens consumers' social presence, consequently elevating the probability of collective excitement. This establishes a mediated chain model, reinforcing repurchase intention. Additionally, the moderation effect analysis indicates that cultural identification negatively moderates both direct paths in the mediated chain model, with particularly pronounced effects for low cultural identification.

This study establishes a closed-loop system in fashion brand product marketing, continuously enhancing the intimacy and interactive willingness between consumers, as well as between consumers and the brand. The objective is to increase brand repurchase rates. Additionally, the research provides valuable recommendations and strategies for fashion brands to adapt to Chinese consumer demands, strengthen emotional attachment between consumers and the brand, and achieve sustainable development in the realm of fashion consumption.

This study aims to evaluate the enhancement in prosthetic supply chain capabilities resulting from the implementation of additive manufacturing (AM) technologies. The study presents an emerging model outlining the key areas that undergo changes when integrating 3D printing technologies into the prosthetic supply chain.

Employing a qualitative approach, data were collected through field observations and 31 in-depth interviews conducted within various Jordanian organizations associated with the prosthetic industry and 3D printing technologies.

The findings suggest that the adoption of 3D printing technologies improves the prosthetic supply chain’s capabilities in terms of customization, responsiveness, innovation, environmental sustainability, cost minimization and patient empowerment. The study sheds light on the specific areas affected in the prosthetic supply chain following the adoption of 3D printing technologies, emphasizing the overall improvement in supply chain capabilities within the prosthetic industry.

This study provides recommendations for governmental bodies and prosthetic organizations to maximize the benefits derived from the use of 3D printing technologies.

This study contributes as the first of its kind in exploring the impact of 3D printing technology adoption in the Jordanian prosthetic industry, elucidating the effects on the supply chain and identifying challenges for decision-makers in an emerging market context.

Many town centres in England exhibit high retail property vacancies and require regeneration. Several alternatives for the replacement of town centre retail (TCR) have been suggested, one of which is healthcare. The healthcare sector in England is in distress, with the National Health Service (NHS) tackling extensive patient waiting lists, whilst operating from an ageing estate. This paper is an introductory study that uses seven carefully selected personalised surveys to raise academic awareness of the importance and potential of integrating healthcare into town centres and calls for large-scale research to establish the statistical validity of the reported observations.

This study is developed from an interpretative standpoint. Through semi-structured interviews with key stakeholders specific to retail-to-healthcare conversions, this study reports stakeholders' perspectives on opportunities and limitations for such conversions to give direction for large statistical research in the future.

All participants support the integration of healthcare into town centres and agreed that diagnostic services, mental health support and primary care services are appropriate for provision within town centres. The participants advocate large-scale change in town centres in England, with integrated healthcare co-located with complementary services to fit with wider regeneration plans. Participants prefer adaptation of existing buildings where technically feasible and emphasise the importance of obtaining the buy-in of other stakeholders whilst expressing concerns about the uncertainty of capital funding availability.

This is the first study to analyse the practice of retail-to-healthcare conversions in town centres. These are still rare in England and projects are complex. The market experience is limited, and thus, the literature is scarce. This study fills this void and provides a starting point for future quantitative research in this area and informs the new town-planning policies.

This study aims to optimize heat transfer efficiency and minimize friction factor and entropy generation in hybrid nanofluid flows through porous media. By incorporating factors such as melting effect, buoyancy, viscous dissipation and no-slip velocity on a stretchable surface, the aim is to enhance overall performance. Additionally, sensitivity analysis using response surface methodology is used to evaluate the influence of key parameters on response functions.

After deriving suitable Lie-group transformations, the modeled equations are solved numerically using the “spectral local linearization method.” This approach is validated through rigorous numerical comparisons and error estimations, demonstrating strong alignment with prior studies.

The findings reveal that higher Darcy numbers and melting parameters are associated with decreased entropy (35.86% and 35.93%, respectively) and shear stress, increased heat transmission (16.4% and 30.41%, respectively) in hybrid nanofluids. Moreover, response surface methodology uses key factors, concerning the Nusselt number and shear stress as response variables in a quadratic model. Notably, the model exhibits exceptional accuracy with $R^2$ values of 99.99% for the Nusselt number and 100.00% for skin friction. Additionally, optimization results demonstrate a notable sensitivity to the key parameters.

Lubrication is a vital method to minimize friction and wear in the automobile sector, contributing significantly to energy efficiency, environmental conservation and carbon reduction. The incorporation of nickel and manganese zinc ferrites into SAE 20 W-40 motor oil lubricants, as defined by the Society of Automotive Engineers, significantly improves their performance, particularly in terms of tribological attributes.

This work stands out for its focus on applications such as hybrid electromagnetic fuel cells and nano-magnetic material processing. While these applications are gaining interest, there is still a research gap regarding the effects of melting on heat transfer in a NiZnFe_2O_4-MnZnFe_2O_4/20W40 motor oil hybrid nanofluid over a stretchable surface, necessitating a thorough investigation that includes both numerical simulations and statistical analysis.