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1 – 10 of 36Cheng Xiong, Bo Xu and Zhenqian Chen
This study aims to investigate the rarefaction effects on flow and thermal performances of an equivalent sand-grain roughness model for aerodynamic thrust bearing.
Abstract
Purpose
This study aims to investigate the rarefaction effects on flow and thermal performances of an equivalent sand-grain roughness model for aerodynamic thrust bearing.
Design/methodology/approach
In this study, a model of gas lubrication thrust bearing was established by modifying the wall roughness and considering rarefaction effect. The flow and lubrication characteristics of gas film were discussed based on the equivalent sand roughness model and rarefaction effect.
Findings
The boundary slip and the surface roughness effect lead to a decrease in gas film pressure and temperature, with a maximum decrease of 39.2% and 8.4%, respectively. The vortex effect present in the gas film is closely linked to the gas film’s pressure. Slip flow decreases the vortex effect, and an increase in roughness results in the development of slip flow. The increase of roughness leads to a decrease for the static and thermal characteristics.
Originality/value
This work uses the rarefaction effect and the equivalent sand roughness model to investigate the lubrication characteristics of gas thrust bearing. The results help to guide the selection of the surface roughness of rotor and bearing, so as to fully control the rarefaction effect and make use of it.
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Amar Benkhaled, Amina Benkhedda, Braham Benaouda Zouaoui and Soheyb Ribouh
Reducing aircraft fuel consumption has become a paramount research area, focusing on optimizing operational parameters like speed and altitude during the cruise phase. However…
Abstract
Purpose
Reducing aircraft fuel consumption has become a paramount research area, focusing on optimizing operational parameters like speed and altitude during the cruise phase. However, the existing methods for fuel reduction often rely on complex experimental calculations and data extraction from embedded systems, making practical implementation challenging. To address this, this study aims to devise a simple and accessible approach using available information.
Design/methodology/approach
In this paper, a novel analytic method to estimate and optimize fuel consumption for aircraft equipped with jet engines is proposed, with a particular emphasis on speed and altitude parameters. The dynamic variations in weight caused by fuel consumption during flight are also accounted for. The derived fuel consumption equation was rigorously validated by applying it to the Boeing 737–700 and comparing the results against the fuel consumption reference tables provided in the Boeing manual. Remarkably, the equation yielded closely aligned outcomes across various altitudes studied. In the second part of this paper, a pioneering approach is introduced by leveraging the particle swarm optimization algorithm (PSO). This novel application of PSO allows us to explore the equation’s potential in finding the optimal altitude and speed for an actual flight from Algiers to Brussels.
Findings
The results demonstrate that using the main findings of this study, including the innovative equation and the application of PSO, significantly simplifies and expedites the process of determining the ideal parameters, showcasing the practical applicability of the approach.
Research limitations/implications
The suggested methodology stands out for its simplicity and practicality, particularly when compared to alternative approaches, owing to the ready availability of data for utilization. Nevertheless, its applicability is limited in scenarios where zero wind effects are a prevailing factor.
Originality/value
The research opens up new possibilities for fuel-efficient aviation, with a particular focus on the development of a unique fuel consumption equation and the pioneering use of the PSO algorithm for optimizing flight parameters. This study’s accessible approach can pave the way for more environmentally conscious and economical flight operations.
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Biswajit Patra and Narayan Sethi
This paper analyzes the direct effect of financial development and the mediating impact of financial development through foreign direct investment (FDI), foreign aid and trade on…
Abstract
Purpose
This paper analyzes the direct effect of financial development and the mediating impact of financial development through foreign direct investment (FDI), foreign aid and trade on economic growth for all Asian countries.
Design/methodology/approach
A fixed-effect model with Driscoll–Kraay panel corrected estimators was employed to find the direct and mediating impact of financial developments on growth for all 47 Asian economies from 1980 to 2020. The bootstrapped panel-quantile regression (BPQR) model is used to check how this effect varies for different income groups of countries.
Findings
The results demonstrated that financial development positively impacts countries' economic growth. The interaction effect of financial development with FDI, foreign aid and foreign trade negatively impacts economic growth. The BPQR results showed that FDI and foreign aid help in the growth of lower quantile economies; however, the impact is negative for middle- and upper-income countries. Trade impacts growth positively for all the quantiles of economies.
Research limitations/implications
The results suggest that the Asian economies must continue to provide thrust on the financial development of their own countries to achieve better growth. It also implied that the dependence on external finance is good for low-income countries and not advisable for middle- and upper-income countries.
Originality/value
To the best of the authors’ knowledge, the current study is the first to provide empirical evidence on analyzing both the direct and interaction effect of financial development on economic growth by considering all the Asian economies.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-09-2022-0587
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R.G. Priyaadarshini and Lalatendu Kesari Jena
The paper aims to propose and validate a process-based model to enhance managerial effectiveness among micro, small and medium enterprises (MSMEs). It has been observed that…
Abstract
Purpose
The paper aims to propose and validate a process-based model to enhance managerial effectiveness among micro, small and medium enterprises (MSMEs). It has been observed that business uncertainties and inadequate financial resources that MSME entrepreneurs and managers face require them to constantly engage in strong self-awareness and self-regulating behavior to enhance the efficacy in their roles and, henceforth, their role performance effectiveness.
Design/methodology/approach
The approach for data collection was based on the clustering of MSMEs belonging to the clusters machine tool, pump manufacturing, foundry, textile and auto-component clusters in India. The respondents to the study were MSME entrepreneurs and managers who oversee and manage multiple functions like operations, quality, marketing, sales, supply chain management, procurement, personnel and administration and general administration.
Findings
The self-efficacy of entrepreneurial managers of MSMEs is observed to play an integral role in enhancing the efficacy of their roles, thus highlighting the use of a process-based perspective while dealing with constant resource constraints and excessive dynamism in their business contexts. The ability to handle multiple tasks effectively and resilience to manage challenges enhances their role-making process, which is significant in achieving and sustaining goal-oriented behavior among MSME entrepreneurs and managers.
Practical implications
This paper would serve as an effective model for entrepreneurs and managers to enhance their efficacy in the individual and interdependent role context, which would help achieve their individual and organizational goals. The model emphasizes a process-based perspective that thrusts the need to relate to the organizational context, enhancing individual confidence for goal-related behavior and fulfilling their role-related expectations.
Originality/value
This paper presents a model of enhancing managerial effectiveness that discusses self-efficacy as antecedent behavior. Here, personal and environmental factors aid cognition to one’s capability to construct reality, self-regulate, encode information and engage in effective managerial action.
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Abraham Ansong, Rhodaline Abena Addison, Moses Ahomka Yeboah and Linda Obeng Ansong
This study aims to investigate the mediation effects of employee voice and employee well-being on the relationship between relational leadership and organizational citizenship…
Abstract
Purpose
This study aims to investigate the mediation effects of employee voice and employee well-being on the relationship between relational leadership and organizational citizenship behavior.
Design/methodology/approach
This study used a Web-based survey method to collect data from 301 respondents in the four public hospitals of the Sekondi-Takoradi Metropolis. This study used PLS-SEM (WarpPLS) to test the study’s hypotheses.
Findings
The findings show that relational leadership has a positive impact on organizational citizenship behavior, and that this link is mediated in part by both employee voice and employee well-being.
Practical implications
This study demonstrates the importance of leaders, paying close attention to employees’ well-being and opinions when attempting to drive organizational citizenship behavior in the health sector.
Originality/value
Based on the review of the extant literature on the impact of leadership on employee behavior and to the best of the authors’ knowledge, it is likely that this study will be the first to show how relational leadership, employee voice, employee well-being and organizational citizenship behavior are related in the health sector, thereby advancing the thrusts of the social exchange and relational leadership theories.
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Qingyang Wang, Weifeng Wu, Ping Zhang, Chengqiang Guo and Yifan Yang
To guide the stable radius clearance choice of water-lubricated bearings for single screw compressors, this paper aims to analyze the effects of turbulence and cavitation on…
Abstract
Purpose
To guide the stable radius clearance choice of water-lubricated bearings for single screw compressors, this paper aims to analyze the effects of turbulence and cavitation on bearing performance under two conditions of specified external load and radius clearance.
Design/methodology/approach
A modified Reynolds equation considering turbulence and cavitation is adopted, based on the Jakobsson–Floberg–Olsson boundary condition, Ng–Pan model and turbulent factors. The equation is solved using the finite difference method and successive over-relaxation method to investigate the bearing performance.
Findings
The turbulent effect can increase the hydrodynamic pressure and cavitation. In addition, the turbulent effect can lead to an increase in the equilibrium radius clearance. The turbulent region exhibits a higher load capacity and cavitation rate. However, the increased cavitation negatively impacts the frictional coefficient and end flow rate. The impact of turbulence increases as the radius clearance decreases. As the rotating speed increases, the turbulence effect has a greater impact on the bearing characteristics.
Originality/value
The research can provide theoretical support for the design of water-lubricated journal bearings used in high-speed water-lubricated single screw compressors.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0029/
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Yiwei Zhang, Daochun Li, Zi Kan, Zhuoer Yao and Jinwu Xiang
This paper aims to propose a novel control scheme and offer a control parameter optimizer to achieve better automatic carrier landing. Carrier landing is a challenging work…
Abstract
Purpose
This paper aims to propose a novel control scheme and offer a control parameter optimizer to achieve better automatic carrier landing. Carrier landing is a challenging work because of the severe sea conditions, high demand for accuracy and non-linearity and maneuvering coupling of the aircraft. Consequently, the automatic carrier landing system raises the need for a control scheme that combines high robustness, rapidity and accuracy. In addition, to exploit the capability of the proposed control scheme and alleviate the difficulty of manual parameter tuning, a control parameter optimizer is constructed.
Design/methodology/approach
A novel reference model is constructed by considering the desired state and the actual state as constrained generalized relative motion, which works as a virtual terminal spring-damper system. An improved particle swarm optimization algorithm with dynamic boundary adjustment and Pareto set analysis is introduced to optimize the control parameters.
Findings
The control parameter optimizer makes it efficient and effective to obtain well-tuned control parameters. Furthermore, the proposed control scheme with the optimized parameters can achieve safe carrier landings under various severe sea conditions.
Originality/value
The proposed control scheme shows stronger robustness, accuracy and rapidity than sliding-mode control and Proportion-integration-differentiation (PID). Also, the small number and efficiency of control parameters make this paper realize the first simultaneous optimization of all control parameters in the field of flight control.
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Zhuoer Yao, Zi Kan, Daochun Li, Haoyuan Shao and Jinwu Xiang
The purpose of this paper is to solve the challenging problem of automatic carrier landing with the presence of environmental disturbances. Therefore, a global fast terminal…
Abstract
Purpose
The purpose of this paper is to solve the challenging problem of automatic carrier landing with the presence of environmental disturbances. Therefore, a global fast terminal sliding mode control (GFTSMC) method is proposed for automatic carrier landing system (ACLS) to achieve safe carrier landing control.
Design/methodology/approach
First, the framework of ACLS is established, which includes flight glide path model, guidance model, approach power compensation system and flight controller model. Subsequently, the carrier deck motion model and carrier air-wake model are presented to simulate the environmental disturbances. Then, the detailed design steps of GFTSMC are provided. The stability analysis of the controller is proved by Lyapunov theorems and LaSalle’s invariance principle. Furthermore, the arrival time analysis is carried out, which proves the controller has fixed time convergence ability.
Findings
The numerical simulations are conducted. The simulation results reveal that the proposed method can guarantee a finite convergence time and safe carrier landing under various conditions. And the superiority of the proposed method is further demonstrated by comparative simulations and Monte Carlo tests.
Originality/value
The GFTSMC method proposed in this paper can achieve precise and safe carrier landing with environmental disturbances, which has important referential significance to the improvement of ACLS controller designs.
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Corporate social responsibility (CSR) was mandated and institutionalised in India through the Companies Act (2013), a decade ago. It is critical to understand the priorities of…
Abstract
Purpose
Corporate social responsibility (CSR) was mandated and institutionalised in India through the Companies Act (2013), a decade ago. It is critical to understand the priorities of the models used by the companies to effectuate their CSR policy. This paper aims to understand the skewing of interest towards Education and Health interventions. The paper then proposes a framework to cross-level and effectuate CSR programme implementation.
Design/methodology/approach
The qualitative study conducted in-depth interviews of the stakeholders from the CSR environment. The findings are used to derive a model to effectuate CSR in India.
Findings
The findings may be divided into two sub-themes – (a) observations from the field study and (b) integrated solution ecosystem (ISE) framework. The qualitative study and the insights form the first component. The proposed framework which can enhance the efficiency of CSR practices may be found in the second sub-theme.
Research limitations/implications
Operationalisation of the proposed model, if adopted would require integrated efforts from multiple functional departments which could lead to an extended timeframe for implementation. This may eventually lead to a need to revise the model in the making. The research could also include perspectives from governmental stakeholders which is missing here.
Practical implications
The emerging model can present an opportunity for corporates and policymakers to revisit the CSR structure and frameworks. It can also be used to evaluate and audit the CSR practices of companies.
Social implications
The ISE posits a bunch of actionable themes which can deliver an impactful transition from the existing approach to CSR to a more far reaching one. While the ground rules are revisited, the approach also allows a critical departure from a corporate-driven model of engagement with the community. The modifications or corrections in this model would also mean a more inclusive layering of developmental interventions. The diversity which could potentially be brought in to designing interventions can be another key impact.
Originality/value
This paper presents insights for some of the pivotal stakeholders of CSR in countries like India. It presents a possible model of effective and optimal utilisation of CSR spending.
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Ariba Khan, Zebran Khan and Mohammed Kamalun Nabi
The purpose of this paper is to investigate the moderating effect of homophily between trust in social media influencers (SMIs) and credibility of the post in influencer marketing…
Abstract
Purpose
The purpose of this paper is to investigate the moderating effect of homophily between trust in social media influencers (SMIs) and credibility of the post in influencer marketing by incorporating the similarity attraction theory (SAT) and analysing the effect of trust in SMIs on online purchase intention and credibility of the post. This study also explored the mediating role of influencers’ credibility of the post between trust in SMIs and online purchase intention.
Design/methodology/approach
The data were collected from 417 respondents in Jaipur, India, using an online questionnaire via Google Forms. A convenience sampling technique was employed to collect the data. Partial least squares structural equation modelling (PLS-SEM) was used to test the proposed hypotheses with the help of SmartPLS version 4.
Findings
The results exhibit a positive and significant influence of trust in SMIs on credibility of the post and online purchase intention. Also, this study found a positive and significant relationship between credibility of the post and online purchase intention. Additionally, credibility of the post had a positive and significant mediation role in the relationship between trust in SMIs and online purchase intention. In addition, homophily positively moderated the relationship between trust in SMIs and credibility of the post.
Practical implications
The findings of this study can be used by marketing professionals working in the e-commerce industry to ensure their continued in success using the right influencers for their specific target audiences and help them create and implement more effective promotional strategies, increasing brand awareness, announcing sales, using them for creative content and so on.
Originality/value
Until now, there has been no study in the Indian context that has tested the moderation effect of homophily between the trust in SMIs and credibility of the post by incorporating the SAT, according to the researchers’ knowledge. Furthermore, this novel piece of research explored the relationship between trust in SMIs and online purchase intention with credibility of the post as a mediator.
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