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Magnetic fluid has excellent function used as lubricants in bearings and mechanical seals, and the purpose of this study is to investigate the sealing performance in a spiral groove mechanical seal lubricated by magnetic fluid.

The sealing characteristic parameters of the lubricating film between the end faces of two sealing rings were calculated based on the Muijderman narrow groove theory for a spiral groove mechanical seal lubricated by magnetic fluid. The film thickness was determined according to the balanced forces on the rotating ring, and the effects of operating conditions, intensity of the magnetic field and diameter of nanoparticles on the sealing characteristics were investigated.

It has been found that the intensity of magnetic field has a great effect on the viscosity of magnetic fluid, film thickness and friction torque while has a little effect on the mass flux of magnetic fluid. The film thickness, mass flux of magnetic fluid and friction torque increase with the increasing volume fraction, rotating speed and diameter of magnetic nanoparticles in magnetic fluid. The mass flux of magnetic fluid decrease with the increasing closing force, and the friction torque decreases with the increase of media pressure.

The change of intensity of magnetic field can affect the viscosity of magnetic fluid and then changes the sealing performance in a mechanical seal lubricated by magnetic fluid. To reduce the mass flux of magnetic fluid and friction torque, the volume fraction, diameter of solid magnetic particles and film thickness should be 5%–7%, 8–10 nm and 2–9.3 µm, respectively.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2023-0032/

The purpose of this study is to investigate the sealing performance of S-CO₂ dry gas seals (DGSs) by considering the effects of pressure-induced deformation, thermal deformation and coupling deformation.

A hydrodynamic lubrication flow model of S-CO₂ DGS was established, and the model was solved using the finite difference and finite element methods. The pressure-induced deformation and thermal deformation of the sealing ring, as well as the sealing performance under the effects of pressure-induced deformation, thermal deformation and coupling deformation, were obtained.

The deformation of the sealing ring is mainly thermal deformation. The influence of pressure-induced deformation on leakage and gas film stiffness is greater than that of thermal deformation and coupling deformation. However, thermal deformation has a greater impact on friction torque and minimum film thickness than pressure-induced deformation and coupling deformation. The influence of deformations on sealing performance is important.

The sealing performance of S-CO₂ DGSs was analyzed considering the effect of pressure-induced deformation, thermal deformation and coupling deformation, which can provide a theoretical basis for S-CO₂ DGS optimization design.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2023-0120/

The purpose of this paper is to study the dynamic characteristics of mechanical face seals with liquid-lubricated inclined elliptical grooves.

The steady-state and perturbation Reynolds control equations of liquid films were established. The film pressure and the liquid film dynamic coefficients were obtained, impacts of groove structures on the liquid film dynamic characteristic coefficients were analyzed.

The analysis results indicate that the axial dynamic stiffness and damping coefficients of the liquid film seal with inclined elliptical grooves are far greater than those of the angular directions. Furthermore, the dynamic stiffness coefficient of the liquid film with the nonclosed inclined elliptical grooves is higher than those with the closed grooves, whereas the dynamic damping coefficient of the liquid film is lower.

The effects of inclined elliptical groove structures on the dynamic characteristics of the liquid film seal are investigated. The results presented are expected to enrich the theoretical basis of optimizing the dynamic performance of liquid film seals with textures.

This paper aims to study the deformation mechanism of polytetrafluoroethylene (PTFE) oil seal under a wide temperature range cycle.

This study categorizes the oil seal operation into three states: assembly, heating-up and cooling. The deformation equation for the oil seal is developed for each state, considering the continuity between them. The investigation of the oil seal’s deformation trends and mechanisms is performed using the ANSYS Workbench.

The assembling process results in a radial shrinkage of the skeleton, causing the centroid to move toward the axis. During heating-up, the outer diameter of the skeleton slightly expands, whereas the inner diameter sharply contracts toward the axis, leading to a further reduction in the centroid’s distance from the axis. Upon cooling, both the inner and outer diameters continue to contract toward the axis, causing the centroid to persist in its movement toward the axis. Consequently, after undergoing a heating-up and cooling cycle ranging from 20°C to 180°C, the outer diameter of the PTFE oil seal reduces by 0.92 mm from its original deformation, ensuring minimal contact between the skeleton and housing. As a result of the reduced static friction torque at the skeleton, the oil seal rotates along the shaft.

The deformation mechanism of PTFE oil seals under a wide temperature range cycle was investigated, aiming to address the concerns related to the rotation along the shaft and leakage.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2023-0142/

This paper aims to explore the history of Anglican churches in Malaysia and discusses their typical features and their respective maintenance practices.

A narrative review of 84 literacy sources published between 1967 and 2020 on the development and features of Anglican churches in Malaysia, along with recommendations on maintenance practices from the asset and facilities management perspective. The exploration of churches’ features follows three main disciplines in building maintenance according to the Jabatan Kerja Raya Guideline for as-built buildings in Malaysia.

The findings of the study have then been tabulated to form a maintenance framework to recommend suitable maintenance practices on specific building components based on different materials. The paper argues that as places of worship, the assets of religious facilities are intangible compared to any other types of building that serve a tangible function (i.e. shelter, commercial or industrial operation). Throughout the exploration of their maintenance practices suggested by vast sources of literature, it is proven that the maintenance of churches is not as straightforward as merely remedying the defects, but it requires the maintenance to radically minimise any disturbance to their aesthetics, thus making maintenance a more challenging task at churches.

This paper proposes a maintenance framework for Anglican churches in Malaysia by categorising building disciplines and their corresponding building components, which supports future research to improve the maintenance practices of religious facilities.

The purpose of this study is to investigate whether two types of destructive leadership styles – despotic and narcissistic – predict turnover intentions of nurses via emotional exhaustion, drawing from the conservation of resources theory and the unfolding theory of turnover.

This paper used multiwave data collected from 731 nurses working in Palestinian hospitals. Structural equation modeling using partial least squares was used to analyze the data.

Both narcissistic and despotic leadership are associated with turnover intentions directly and indirectly through emotional exhaustion. Despotic leadership, however, has a stronger relationship to turnover intention than narcissistic leadership. Despotic and narcissistic leadership are common in this sample.

A strong psycho-safety climate is likely needed to address the harm caused by these destructive leadership styles, and interventions should span primary, secondary and tertiary levels of the public health model. Examples include ensuring strong organizational checks, balances and information flows, job control, support and widespread training; assistance programs such as counseling services; and remediation and repair for harmed individuals and teams.

This study advances the understanding of the negative, dark or destructive side of leadership specifically in the nursing context. This study compares despotic and narcissistic leadership to examine which one better/worse explains turnover intentions through emotional exhaustion.

The purpose of this paper is to develop and test a research model that explores the interrelationships of employee recognition, job embeddedness (JE), knowledge sharing, service orientation and abusive supervision. Specifically, the model proposes that JE mediates the impact of recognition on knowledge sharing and service orientation, while abusive supervision moderates the indirect influence of recognition on knowledge sharing and service orientation via JE. The model also proposes that JE and knowledge sharing mediate the link between recognition and service orientation in a sequential manner.

Data were gathered from restaurant frontline employees in three waves in Ghana. The hypothesized links were gauged via structural equation modeling using Mplus 7.4.

The vast majority of the hypothesized relationships were supported by the empirical data. Specifically, JE mediated the impact of recognition on knowledge sharing and service orientation. JE and knowledge sharing sequentially mediated the impact of recognition on service orientation. Abusive supervision moderated the positive effect of recognition on JE and JE on knowledge sharing such that the effects were stronger among frontline employees with low levels of abusive supervision. In addition, abusive supervision moderated the indirect effect of recognition on knowledge sharing through JE. On the contrary, abusive supervision did not significantly moderate the linkage between JE and service orientation. This is also true for abusive supervision as a moderator of the indirect influence of recognition on service orientation via JE.

Management should not only focus on financial rewards but also consider non-financial rewards such as employee recognition. This is what is overlooked among practitioners. Therefore, restaurant managers/supervisors should use recognition mechanisms such as certificate of appreciation, plaque of honor and/or oral praises wherever possible to trigger employees’ JE, knowledge sharing and service orientation. Restaurateurs should also arrange training programs for supervisors to make them avoid practicing abusive supervision that would erode JE and knowledge sharing.

Evidence about the organizationally valued consequences of employee recognition in the hospitality literature is sparse. With this realization, this paper advances the current knowledge by gauging JE as a mediator between recognition and knowledge sharing and service orientation. Unlike other empirical pieces, JE and knowledge sharing as the sequential mediators of the effect of recognition on service orientation are tested. This paper advances the current knowledge base by assessing abusive supervision as a moderator concerning the previously mentioned linkages. This paper also contributes to the literature by gauging abusive supervision as a moderator of the indirect impact of recognition on knowledge sharing and service orientation via JE.

The challenges faced by China's high-end equipment manufacturing (HEEM) industry are becoming clearer in the process of global supply chain (GSC) reconfiguration. The purpose of this study is to investigate how China's HEEM industry has been affected by the GSC reconfiguration, as well as its short- and long-term strategies.

The authors adopted a multi-method approach. Interviews were conducted in Phase 1, while a three-round Delphi survey was conducted in Phase 2 to reach consensus at the industry level.

The GSC reconfiguration affected China's HEEM supply chain (SC). Its direct effects include longer lead times, higher purchasing prices and inconsistent supply and inventory levels of key imported components and materials. Its indirect effects include inconsistent product quality and cash flows. In the short term, China's HEEM enterprises have sought to employ localized substitutes, while long-term strategies include continuous technological innovation, industry upgrades and developing SC resilience.

This study not only encourages Chinese HEEM enterprises to undertake a comprehensive examination of their respective industries but also provides practical insights for SC scholars, policymakers and international stakeholders interested in how China's HEEM industry adapts to the GSC reconfiguration and gains global market share.

The purpose of the current research is (1) to test affective mechanisms by which a leader's work engagement predicts team performance via a follower's work engagement in a trickle-down fashion and (2) to examine the moderating role of relational identification with the leader on the trickle-down effect.

Multisource and three-wave data was collected from 404 followers working in 76 teams from a construction company in South Korea. By aggregating all study variables, a 2-2-2 level approach by using the PROCESS macro with bootstrapping (10,000 samples) in SPSS was used to test the proposed model.

The current research uses a team-level analysis to examine (1) the effect of a leader's work engagement on team performance via a follower's work engagement and (2) moderating role of relational identification via the lens of the affective processing theory (APT) and the conservation of resource (COR) theory.

Based the lens of APT and COR theory, the current research found that the contagious effect of a leader's work engagement on followers is conditional. Specifically a leader's work engagement has a positive effect on followers' work engagement only when followers have a high sense of relational identification with their leader. However, a leader's work engagement has an adverse effect on followers when followers have a low sense of relational identification.

In a packaging olives manufacturing system, the drained weight of the product plays a decisive role in customer’s satisfaction as well as in financial saving for the organization. The purpose of this study is to minimize the variation of the drained weight of olives in the production system to avoid the negative consequences.

The research develops a practical implementation step-by-step of Six Sigma define, measure, analyze, improve and control (DMAIC) in reducing the variation of the drained weight of olives.

Data analysis was used at various phases of the project to identify the root causes of rejection and rework. As a result of the necessary interventions and actions to optimize the manufacturing process, the standard deviation of drained weight was significantly reduced by 51.02%, with a 99.97% decrease in the number of parts per million defectives. Thus, the yield of the production process was improved by 8.24%. The estimated annual savings from this project were US$ 228,000 resulting from reduced rejection and rework.

This research may be used in packaging olives production systems as a tool for managers and engineers planning to increase productivity and efficiency while also improving product quality. The study also provided the organization with helpful actions that will be used to guide future Six Sigma operations management on the system. Thus, practical guidelines and solutions are provided.

In this project, for the first time, the Six Sigma methodology has been applied to solve a real-world problem in the packaging olives manufacturing system and to show that the DMAIC approach may assist to improve the efficiency of their operations and hence contribute to their quest toward continuous improvement.