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The water-lubricated hydrodynamic herringbone groove journal bearing (HGJB) is capable of running at high speed. However, when running at a low speed, it suffers from a low load-carrying capacity due to the weak hydrodynamic effect. To overcome this problem, this study proposes a hybrid water-lubricated HGJB and aims to investigate its dynamic characteristics.

A hybrid lubrication model applicable to the hybrid water-lubricated HGJB is established based on the boundary fitted coordinate system, which considers the turbulent, thermal and tilting effects, and the finite difference method is used to calculate the dynamic characteristics of the hybrid water-lubricated HGJB.

The result shows that the hybrid HGJB has larger dynamic coefficients and better system stability compared with the hydrodynamic HGJB when running at low speed. Furthermore, the stiffness of hybrid HGJB are mainly governed by the hydrodynamic effect rather than the hydrostatic effect when running at high speed.

The proposed hybrid water-lubricated HGJB shows excellent dynamic characteristics at either low speed or high speed; and the hybrid water-lubricated HGJB has a large load-carrying capacity when running at low speed and has a good dynamic stability when running at high speed.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0233/

Hybrid working is becoming commonplace, but scientific research on employee preferences for hybrid-working arrangements is still scarce. The current study investigated knowledge-worker preferences for hybrid-working scenarios, considering the relative importance of hybrid-working aspects and differences among knowledge workers associated with differences in preferences.

The study was conducted in a large governmental organization in the Netherlands. Attributes and levels for the choice-based experiment were developed in an iterative process involving several groups of stakeholders. A survey containing sociodemographic and work-related measures and a choice-based experiment was completed by 263 policy officers.

Conjoint analyses showed that the most important attribute was the “Distribution of days” (i.e. the percentage of time at home versus the office). Four employee segments were identified: home workers, hybrid fixed, hybrid flex and office workers, each with a different pattern of preferences. The segments differed on age/tenure, task interdependence, household composition (young children or not) and motives for coming to the office.

The study reveals that differences in preferences are associated with different combinations of demographic and work characteristics rather than one specific characteristic. Findings align with theories on work–life balance, (family) life-cycle stages and needs-supply fit.

Study findings support managerial decision-making on which hybrid-working scenario(s) to implement, considering the preferences of different groups of employees.

The study contributes to the literature on hybrid working and represents a novel application of conjoint analysis.

The complexity of contemporary societal challenges in emerging countries reanimates the necessity of collective action to resolve them. What is required is system change, namely, transformations in policy, practice, power relationships, market dynamics and social customs that underlie social and environmental issues. Technological innovations, paired with intentional social changes, might play a transformative role in this effort. This paper aims to investigate the relationship between the adoption of technologies in social enterprises (SEs) and their contribution to achieving system change. It also addresses the effects of their hybrid nature on this relationship.

The analysis relied on data collected through a survey of the global population of Ashoka fellows, which is largely based in emerging economies. Three models were developed concerning different pathways to achieve system change identified in the theoretical framework. These were tested using Probit regressions.

The investigation confirms that technology can support SEs in navigating complex pathways to achieve system change rather than merely enabling linear scaling operational strategies. The pursuit of economic value creation, in conjunction with a social mission, decreases the ability of SEs to achieve system change. This is because the scaling paths which hardly create revenues are neglected.

The study conceptualises a multifaceted model of system change. It tests the framework empirically to show that SEs can adopt technologies to unleash complex system change processes to generate societal impact, on top of merely demonstrating linear approaches to scaling or replication. The paper questions the capacity of SEs to facilitate system change without appropriate financial support and the inherent tensions between hybridity and the depth of system change dynamics.

Magnetohydrodynamics (MHD) in nanofluids is crucial in boundary layer flow as it enables the manipulation of fluid motion through magnetic fields, which leads to improved stability and efficiency. This study aims to introduce a model and solutions for the boundary layer flow of a ternary hybrid nanofluid past a permeable shrinking sheet, integrating both magnetohydrodynamic and slip effects.

The model is firstly expressed as partial differential equations and subsequently converted into ordinary differential equations (ODEs) through a similarity transformation technique. A finite difference scheme with the Lobatto IIIa formula in MATLAB is applied to numerically solve the ODEs, where the respective outcomes provide insights into the skin friction coefficient, Nusselt number, velocity profiles and temperature profiles.

The results highlight the significance of enhancing magnetohydrodynamic effects and first-order velocity slip to reduce skin friction, improve heat transfer, delay boundary layer separation, increase flow velocity and lower fluid temperature. In addition, the stable numerical solution is scrutinized using response surface methodology (RSM) to validate and optimize flow control. The RSM optimization confirms that higher suction, magnetohydrodynamic effects and first-order slip levels are essential for minimizing skin friction and maximizing heat transfer simultaneously.

The presented model together with the numerical and statistical results can be used as a guidance to control the flow and heat transfer that occur within a related practical application, especially in engineering and industrial activities such as cooling technologies, energy harvesting or fluid transport in nanotechnology, where precise control of heat transfer and fluid dynamics is essential for optimizing performance and reducing energy consumption.

This paper aims to present a new trajectory scheduling method to generate a smooth and continuous trajectory for a hybrid machining robot.

The trajectory scheduling method includes two steps. First, a G3 continuity local smoothing approach is proposed to smooth the toolpath. Then, considering the tool/joint motion and geometric error constraints, a jerk-continuous feedrate scheduling method is proposed to generate the trajectory.

The simulations and experiments are conducted on the hybrid robot TriMule-800. The simulation results demonstrate that this method is effectively applicable to machining trajectory scheduling for various parts and is computationally friendly. Moreover, it improves the robot machining speed and ensures smooth operation under constraints. The results of the S-shaped part machining experiment show that the resulting surface profile error is below 0.12 mm specified in the ISO standard, confirming that the proposed method can ensure the machining accuracy of the hybrid robot.

This paper implements an analytical local toolpath smoothing approach to address the non-high-order continuity problem of the toolpath expressed in G code. Meanwhile, the feedrate scheduling method addresses the segmented paths after local smoothing, achieving smooth and continuous trajectory generation to balance machining accuracy and machining efficiency.

This study aims to identify the significant scientific actors, reveal the intellectual structure and explore essential features for future research direction in Sharia governance studies.

The study applies a hybrid review combining bibliometric analysis and content analysis. It uses Rstudio (biblioshiny), VOSviewer and Microsoft Excel to analyze 457 articles published in 206 journals indexed by Scopus and/or Web of Science during the period of 1985 until the end of 2022.

The paper discovered four distinct streams of Sharia governance studies: structure of Sharia governance, Sharia governance and risk management, Sharia governance and sustainability and the effect of Sharia governance toward firm’s financial performance. Furthermore, it derives and summarizes 26 main research questions for future studies.

In terms of theoretical implications, the finding contributes to the general literature on Sharia governance by conducting bibliometric analysis and content analysis. In terms of practical implications, this study suggests that Sharia governance should be strengthened by the management of Islamic banks and other Islamic-based businesses.

To the best of the authors’ knowledge, this study is among the early studies using a hybrid review on the topic of Sharia governance, allowing future researchers in this field to capture the trends and progress of current literature as well as the research gaps to be filled in by future researchers.

Exact solution of time–cost trade-off problem (TCTP) by the state-of-the-art meta-heuristic algorithms can be obtained for small- and medium-scale problems, while satisfactory results cannot be obtained for large construction projects. In this study, a hybrid heuristic meta-heuristic algorithm that adapts the search domain is developed to solve the large-scale discrete TCTP more efficiently.

Minimum cost slope–based heuristic network analysis algorithm (NAA), which eliminates the unfeasible search domain, is embedded into differential evolution meta-heuristic algorithm. Heuristic NAA narrows the search domain at the initial phase of the optimization. Moreover, activities with float durations higher than the predetermined threshold value are eliminated and then the meta-heuristic algorithm starts and searches the global optimum through the narrowed search space. However, narrowing the search space may increase the probability of obtaining a local optimum. Therefore, adaptive search domain approach is employed to make reintroduction of the eliminated activities to the design variable set possible, which reduces the possibility of converging into local minima.

The developed algorithm is compared with plain meta-heuristic algorithm with two separate analyses. In the first analysis, both algorithms have the same computational demand, and in the latter analysis, the meta-heuristic algorithm has fivefold computational demand. The tests on case study problems reveal that the developed algorithm presents lower total project costs according to the dependent t-test for paired samples with α = 0.0005.

In this study, TCTP is solved without considering quality or restrictions on the resources.

The proposed method enables to adapt the number of parameters, that is, the search domain and provides the opportunity of obtaining significant improvements on the meta-heuristic algorithms for other engineering optimization problems, which is the theoretical contribution of this study. The proposed approach reduces the total construction cost of the large-scale projects, which can be the practical benefit of this study.

This paper aims to control the clay’s dispersion within the PA6 matrix. Cloisite Na+, a naturally occurring sodium montmorillonite (NaMMT), and Cloisite 30B and 93A, two organophilic MMT (OMMT), were used for this purpose.

By using a twin-screw extruder for melt mixing, Polyamide 6 (PA6)/NaMMT nanocomposites with 1, 3, 5 and 10 Wt.% Cloisite Na+ and PA with 5 and 10 Wt.% Cloisite 30B and 93A were created. PA6/OMMT nanocomposite to investigate how organoclay disperses within the PA6.

The link among PA6 and the silicate layer was evaluated via (FTIR), confirming presence of a compact contact between the nanosilicate layer and PA6 segments. Thermal behavior of obtained nanocomposites was evaluated through a thermogravimetric analyzer. The data confirmed that the thermal behavior of PA6 was moderately improved once addition 5 Wt.% filler, in the order: Cloisite Na+>Cloisit 93A>Cloisit 30B.Electrical properties have been studied through measuring dielectric constant, dielectric loss and conductivity measurment that procced at frequencies from 10^–1 to 107 Hz and temperatures from 40°C to 120°C, dielectric constant (έ) and dielectric loss (έ) of the nanocomposite were sharply increased with increasing the two parameters temperature and frequency.

The hybrid nanomaterials of PA6/ Cloisite Na+, Cloisite 93A or Cloisite 30B can be credited as electronic nanodevices and microwave semiconductors materials with a small amount of nanoclay filler as illustrated in the conclusion.

This study presents the development of a supply chain (SC) observatory, which is a benchmarking solution to support companies within the same industry in understanding their positioning in terms of SC performance.

A case study is used to demonstrate the set-up of the observatory. Twelve experts on automatic equipment for the wrapping and packaging industry were asked to select a set of performance criteria taken from the literature and evaluate their importance for the chosen industry using multi-criteria decision-making (MCDM) techniques. To handle the high number of criteria without requiring a high amount of time-consuming effort from decision-makers (DMs), five subjective, parsimonious methods for criteria weighting are applied and compared.

A benchmarking methodology is presented and discussed, aimed at DMs in the considered industry. Ten companies were ranked with regard to SC performance. The ranking solution of the companies was on average robust since the general structure of the ranking was very similar for all five weighting methodologies, though simplified-analytic hierarchy process (AHP) was the method with the greatest ability to discriminate between the criteria of importance and was considered faster to carry out and more quickly understood by the decision-makers.

Developing an SC observatory usually requires managing a large number of alternatives and criteria. The developed methodology uses parsimonious weighting methods, providing DMs with an easy-to-use and time-saving tool. A future research step will be to complete the methodology by defining the minimum variation required for one or more criteria to reach a specific position in the ranking through the implementation of a post-fact analysis.

This study aims to provide insights into the experiences of working from home (WFH) in a global context from the perspective of perceived productivity.

This paper uses a multivariate analysis benefiting from an extensive data set of almost 137,500 respondents from 88 countries.

This paper find that most respondents are satisfied with their productivity when WFH: 70% agree or strongly agree with “My home environment enables me to work productively”. The results further show that socio-demographic factors, as well as the social and physical settings at home, are associated with the perceptions of productivity. Being younger, dissatisfied with the physical setting and the presence of others at home seem to decrease the probability of being satisfied with productivity, whereas being female seems to increase it. However, some differences between countries exist when controlling for socio-demographic factors, presence of others and physical setting at home.

The results enhance understanding of perceived productivity in different countries while WFH and provide valuable insights for employers, employees and policymakers on how to support WFH effectively.

The value of this paper lies in its investigation of socio-demographic factors, as well as the social and physical home environment, in relation to perceptions of productivity within a truly global context, while also comparing differences between countries.