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1 – 10 of 29Eylem Thron, Shamal Faily, Huseyin Dogan and Martin Freer
Railways are a well-known example of complex critical infrastructure, incorporating socio-technical systems with humans such as drivers, signallers, maintainers and passengers at…
Abstract
Purpose
Railways are a well-known example of complex critical infrastructure, incorporating socio-technical systems with humans such as drivers, signallers, maintainers and passengers at the core. The technological evolution including interconnectedness and new ways of interaction lead to new security and safety risks that can be realised, both in terms of human error, and malicious and non-malicious behaviour. This study aims to identify the human factors (HF) and cyber-security risks relating to the role of signallers on the railways and explores strategies for the improvement of “Digital Resilience” – for the concept of a resilient railway.
Design/methodology/approach
Overall, 26 interviews were conducted with 21 participants from industry and academia.
Findings
The results showed that due to increased automation, both cyber-related threats and human error can impact signallers’ day-to-day operations – directly or indirectly (e.g. workload and safety-critical communications) – which could disrupt the railway services and potentially lead to safety-related catastrophic consequences. This study identifies cyber-related problems, including external threats; engineers not considering the human element in designs when specifying security controls; lack of security awareness among the rail industry; training gaps; organisational issues; and many unknown “unknowns”.
Originality/value
The authors discuss socio-technical principles through a hexagonal socio-technical framework and training needs analysis to mitigate against cyber-security issues and identify the predictive training needs of the signallers. This is supported by a systematic approach which considers both, safety and security factors, rather than waiting to learn from a cyber-attack retrospectively.
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Jie Wan, Biao Chen, Jianghua Shen, Katsuyoshi Kondoh, Shuiqing Liu and Jinshan Li
The metallic alloys and their components fabricated via laser powder bed fusion (LPBF) suffer from the microvoids formed inevitably due to the extreme solidification rate during…
Abstract
Purpose
The metallic alloys and their components fabricated via laser powder bed fusion (LPBF) suffer from the microvoids formed inevitably due to the extreme solidification rate during fabrication, which are impossible to be removed by heat treatment. This paper aims to remove those microvoids in as-built AlSi10Mg alloys by hot forging and enhance their mechanical properties.
Design/methodology/approach
AlSi10Mg samples were built using prealloyed powder with a set of optimized LPBF parameters, viz. 350 W of laser power, 1,170 mm/s of scan speed, 50 µm of layer thickness and 0.24 mm of hatch spacing. As-built samples were preheated to 430°C followed by immediate pressing with two different thickness reductions of 10% and 35%. The effect of hot forging on the microstructure was analyzed by means of X-ray diffraction, scanning electron microscopy, electron backscattered diffraction and transmission electron microscopy. Tensile tests were performed to reveal the effect of hot forging on the mechanical properties.
Findings
By using hot forging, the large number of microvoids in both as-built and post heat-treated samples were mostly healed. Moreover, the Si particles were finer in forged condition (∼150 nm) compared with those in heat-treated condition (∼300 nm). Tensile tests showed that compared with heat treatment, the hot forging process could noticeably increase tensile strength at no expense of ductility. Consequently, the toughness (integration of tensile stress and strain) of forged alloy increased by ∼86% and ∼24% compared with as-built and heat-treated alloys, respectively.
Originality/value
Hot forging can effectively remove the inevitable microvoids in metals fabricated via LPBF, which is beneficial to the mechanical properties. These findings are inspiring for the evolution of the LPBF technique to eliminate the microvoids and boost the mechanical properties of metals fabricated via LPBF.
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Hatice Merve Yanardag Erdener and Ecem Edis
Living walls (LWs), vegetated walls with an integrated growth layer behind, are being increasingly incorporated in buildings. Examining plant characteristics’ comparative impacts…
Abstract
Purpose
Living walls (LWs), vegetated walls with an integrated growth layer behind, are being increasingly incorporated in buildings. Examining plant characteristics’ comparative impacts on LWs’ energy efficiency-related thermal behavior was aimed, considering that studies on their relative effects are limited. LWs of varying leaf albedo, leaf transmittance and leaf area index (LAI) were studied for Antalya, Turkey for typical days of four seasons.
Design/methodology/approach
Dynamic simulations run by Envi-met were used to assess the plant characteristics’ influence on seasonal and orientation-based heat fluxes. After model calibration, a sensitivity analysis was conducted through 112 simulations. The minimum, mean and maximum values were investigated for each plant characteristic. Energy need (regardless of orientation), temperature and heat flux results were compared among different scenarios, including a building without LW, to evaluate energy efficiency and variables’ impacts.
Findings
LWs reduced annual energy consumption in Antalya, despite increasing energy needs in winter. South and west facades were particularly advantageous for energy efficiency. The impacts of leaf albedo and transmittance were more significant (44–46%) than LAI (10%) in determining LWs’ effectiveness. The changes in plant characteristics changed the energy needs up to ca 1%.
Research limitations/implications
This study can potentially contribute to generating guiding principles for architects considering LW use in their designs in hot-humid climates.
Originality/value
The plant characteristics’ relative impacts on energy efficiency, which cannot be easily determined by experimental studies, were examined using parametric simulation results regarding three plant characteristics.
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Nandini Sharma and Boeing Laishram
Construction industry faces challenges in making objective decisions due to monetary value attached to quality. Among various quality management techniques available, cost of…
Abstract
Purpose
Construction industry faces challenges in making objective decisions due to monetary value attached to quality. Among various quality management techniques available, cost of quality (COQ) is one such method used to address the concern. However, the absence of measurable COQ factors to monitor quality costs hampers the implementation of COQ framework in the construction industry. Therefore, this study aims to identify COQ factors focused on visible factors (VF) and hidden factors (HF) and the current requirements to achieve it.
Design/methodology/approach
This study is based on Preferred Reporting Items for Systematic Review and Meta-Analyses protocol guidelines. The present study identified 57 articles published between 1992 and 2023 in peer-reviewed journals.
Findings
The findings reveal 22 factors, which are grouped into four categories based on COQ. Through systematic review, the authors observed limited methodological and theoretical diversity. In fact, there are no quantitative frameworks to calculate COQ. The study, therefore, developed a framework comprising four major routes/paths of COQ factors within the framework.
Practical implications
The COQ routes developed through this study will enable the practitioners to meticulously categorise VF and HF, facilitating quantifying of quality throughout the lifecycle of project, which is currently absent from the existing quality assurance/quality control (QA/QC) approach. In addition, these COQ routes stand as essential construction strategies, significantly enhancing outcomes related to time, cost, quality, sustainability and fostering closer relationships within project frameworks.
Originality/value
The current study contributes significantly to the existing body of knowledge by developing various COQ routes and proposing future research directions to address gaps in the literature.
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Hongqiang Sang, Fang Huang, Wei Lu, Rui Han and Fen Liu
The patient-side manipulator (PSM) achieves high torque capability by combining harmonic servo system with high reduction ratio and low torque motor. However, high reduction ratio…
Abstract
Purpose
The patient-side manipulator (PSM) achieves high torque capability by combining harmonic servo system with high reduction ratio and low torque motor. However, high reduction ratio can increase inertia and decrease compliance of the manipulator. To enhance the backdrivability of the minimally invasive surgical robot, this paper aims to propose a resistance torque compensation algorithm.
Design/methodology/approach
A resistance torque compensation algorithm based on dynamics and Luenberger observer is proposed. The dynamics are established, considering joint flexibility and an improved Stribeck friction model. The dynamic parameters are experimentally identified by using the least squares method. With the advantages of clear structure, simple implementation and fast solution speed, the Luenberger observer is selected to estimate the unmeasured dynamic information of PSM and realize the resistance torque compensation.
Findings
For low-speed surgical robots, the centrifugal force term in the dynamic model can be simplified to reduce computational complexity. Joint flexibility and an improved Stribeck friction model can be considered to improve the accuracy of the dynamic model. Experiment results show that parameter identification and estimated results of the Luenberger observer are accurate. The backdrivability of the PSM is enhanced in ease and smoothness.
Originality/value
This algorithm provides potential application prospects for surgical robots to maintain high torque while remaining compliant. Meanwhile, the enhanced backdrivability of the manipulator helps to improve the safety of the preoperative manual adjustment.
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Kai Xu, Ying Xiao and Xudong Cheng
The purpose of this study is to investigate the effects of nanoadditive lubricants on the vibration and noise characteristics of helical gears compared with conventional…
Abstract
Purpose
The purpose of this study is to investigate the effects of nanoadditive lubricants on the vibration and noise characteristics of helical gears compared with conventional lubricants. The experiment aims to analyze whether nanoadditive lubricants can effectively reduce gear vibration and noise under different speeds and loads. It also analyzes the sensitivity of the vibration reduction to load and speed changes. In addition, it compares the axial and radial vibration reduction effects. The goal is to explore the application of nanolubricants for vibration damping and noise reduction in gear transmissions. The results provide a basis for further research on nanolubricant effects under high-speed conditions.
Design/methodology/approach
Helical gears of 20CrMnTi were lubricated with conventional oil and nanoadditive oils. An open helical gearbox with spray lubrication was tested under different speeds (200–500 rpm) and loads (20–100 N·m). Gear noise was measured by a sound level meter. Axial and radial vibrations were detected using an M+P VibRunner system and fast Fourier transform analysis. Vibration spectrums under conventional and nanolubrication were compared. Gear tooth surfaces were observed after testing. The experiment aimed to analyze the noise and vibration reduction effects of nanoadditive lubricants on helical gears and the sensitivity to load and speed.
Findings
The key findings are that nanoadditive lubricants significantly reduce the axial and radial vibrations of helical gears under low-speed conditions compared with conventional lubricants, with a more pronounced effect on axial vibrations. The vibration reduction is more sensitive to rotational speed than load. At the same load and speed, nanolubrication reduces noise by 2%–5% versus conventional lubrication. Nanoparticles change the friction from sliding to rolling and compensate for meshing errors, leading to smoother vibrations. The nanolubricants alter the gear tooth surfaces and optimize the microtopography. The results provide a basis for exploring nanolubricant effects under high speeds.
Originality/value
The originality and value of this work is the experimental analysis of the effects of nanoadditive lubricants on the vibration and noise characteristics of hard tooth surface helical gears, which has rarely been studied before. The comparative results under different speeds and loads provide new insights into the vibration damping capabilities of nanolubricants in gear transmissions. The findings reveal the higher sensitivity to rotational speed versus load and the differences in axial and radial vibration reduction. The exploration of nanolubricant effects on gear tribological performance and surface interactions provides a valuable reference for further research, especially under higher speed conditions closer to real applications.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0220/
Hanudin Amin, Faizah Panggi, Imran Mehboob Shaikh and Muhamad Abduh
The purpose of this study is to develop a new framework to measure waqif preference of waqf-based qardhul hassan financing in Malaysia.
Abstract
Purpose
The purpose of this study is to develop a new framework to measure waqif preference of waqf-based qardhul hassan financing in Malaysia.
Design/methodology/approach
Using a maqāṣid approach, this study’s data were drawn from 286 valid usable questionnaires to examine the effects of consumer, family, ummah and humanity factors on the preference.
Findings
The study found that the said factors sourced from Attia’s maqāṣid al-Shariah were instrumental in determining waqif preference to donate in waqf-based qardhul hassan financing.
Research limitations/implications
Like others, this study’s findings are limited in terms of their generalisations and applications. The theory, context and variables used should be expanded in future works.
Practical implications
The results obtained are useful as a yardstick to enable the offered waqf-based qardhul hassan financing for improved mutual well-being among different classes of the wealth of societal groups in Malaysia. Furthermore, the results provide valuable insights into the direction for practitioners mainly managers involved in introducing waqf-based qardhul hassan financing as a new Islamic social financial instrument for poor and needy folks, at best.
Originality/value
This study is novel in terms of the proposed conceptual framework, where the waqif perspective comes into play.
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Michael Harrison and Louisa Rennie
This chapter explores the development of middle leaders in the specific context of Catholic schools. It considers the interplay between contemporary thinking on educational…
Abstract
This chapter explores the development of middle leaders in the specific context of Catholic schools. It considers the interplay between contemporary thinking on educational leadership and the insights of Catholic theology and ministry. Two key themes foundational to this interplay are examined: the connection between leading and following, and the central importance of relationships for leadership. For each of these themes, the reader is provided with related questions for middle leaders in a Catholic school context, an activity for engaging with leaders, and an exercise inviting middle school leaders to reflect on their own experience and the context within which they lead.
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The purpose of this study has to conduct an integrated effective evaluation system to discover consumers' travel attitudes of the culinary experiences or cuisines and establishing…
Abstract
Purpose
The purpose of this study has to conduct an integrated effective evaluation system to discover consumers' travel attitudes of the culinary experiences or cuisines and establishing an optimal mutual relationship of a brand equity evaluation model.
Design/methodology/approach
Based on a sample of 624 participants, the results support that social media engagement has indirect effects on culinary brand equity development through travel attitudes and information sharing.
Findings
The study finds that values are expressed as foundational attributes that have indirect effects on brand equity through hedonic function, perceived quality, brand awareness and brand image. In contrast, the social interaction mechanism strengthens subdimensional relationships. These findings extend the customer brand equity literature and the nature of tourists' perspectives in the context of Taiwan's culinary destination brand equity.
Practical implications
It is a suggestion for tourism and hospitality managers to identify the different characteristics of attitudes towards visits and the customers' desert of participation in food-related activities when it derives to the classifications of food and culinary tourism.
Originality/value
The current study extended the findings and asserted that social interaction leads to and strengthens the relationships between memorable culinary hedonic experiences and perceived quality and improves tourists' positive awareness and image compared to other tourism experiences.
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Xiaowen Chen, Wanlin Xie, Song Tang, Meng Zhang, Hao Song, Qingzheng Ran and Defen Zhang
The purpose of this study is to examine the impact of MoS2 on the microstructure and characteristics of micro-arc oxidized (MAO) ceramic coatings created on ZK60 magnesium alloy…
Abstract
Purpose
The purpose of this study is to examine the impact of MoS2 on the microstructure and characteristics of micro-arc oxidized (MAO) ceramic coatings created on ZK60 magnesium alloy through the addition of varying concentrations of MoS2 particles to the electrolyte, aiming to enhance the corrosion resistance of magnesium alloy.
Design/methodology/approach
The surface morphology, roughness and phase composition of the coatings were analyzed using scanning electron microscopy, a hand-held roughness tester and an X-ray diffractometer, respectively, and the corrosion resistance of the MAO coatings prepared by the addition of different contents of MoS2 particles was tested and analyzed using an electrochemical workstation.
Findings
The results demonstrate that MoS2/MgO composite coatings have been successfully prepared on the surface of magnesium alloys through micro-arc oxidation. Furthermore, the corrosion resistance of the ZK60 magnesium alloy prepared with the addition of 1.0 g/L MoS2 was the best compared to the other samples.
Originality/value
MoS2 particles were able to penetrate the coatings successfully during the micro-arc oxidation process, acting as a barrier in the micropores to prevent the corrosion medium from touching the surface, thus improving the corrosion resistance of the sample. The electrochemical workstation was used to study the corrosion resistance of the MoS2/MAO coating on the ZK60 magnesium alloy.
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