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Article
Publication date: 9 July 2024

Xin Guo, Jiesong Tu, Zhibin Fan, Baoshuai Du, Hongfei Shang, Jiangfeng An and Dan Jia

Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship…

Abstract

Purpose

Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship between the corrosion thinning of carbon steel for transmission towers and the degradation of its mechanical properties.

Design/methodology/approach

A macroscopic finite element model of a transmission tower was established and then combined with the corrosion thinning and mechanical properties of Q355 steel in different test periods measured in neutral salt spray, SO2 atmosphere and wet heat environments to conduct a finite element simulation of a transmission tower with different corrosion thinning of Q355 steel.

Findings

When the residual thickness of the tower leg angle was reduced to 4.03 mm, the maximum stress solved in the simulation exceeded the yield strength, with the tower already at risk of collapse owing to corrosion failure under extreme conditions of basic wind speed.

Originality/value

This study innovatively utilises transmission tower finite element models and experimental data from mechanical degradation experiments to quantify the relationship between corrosion thinning and the mechanical properties of Q355 steel, ensuring the effective assessment of the mechanical properties of corroded transmission towers.

Details

Anti-Corrosion Methods and Materials, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 9 October 2023

Ahmet Galip Gençyürek

The crude oil market plays a key role in addressing the issue of energy economics. This paper aims to detect the causality relationship between the crude oil market and economy…

Abstract

Purpose

The crude oil market plays a key role in addressing the issue of energy economics. This paper aims to detect the causality relationship between the crude oil market and economy based on the financial system.

Design/methodology/approach

This paper used the static and dynamic Hatemi-J Bootstrap Toda–Yamamoto and Diebold–Yilmaz connectedness index. The Hatemi-J Bootstrap Toda-Yamamoto approach allows researchers to use nonstationary data and that method is robust to nonnormal distribution and heteroscedasticity. The Diebold–Yilmaz connectedness index model provides researchers to detect the power of connectedness besides linkage direction. The analyzed period is the span from January 3, 2005 to October 3, 2022.

Findings

The results show bidirectional causality in the full sample but unidirectional causality before and after the 2008 financial crisis. During the 2008 financial crisis period and the COVID-19 period, there was a bidirectional and unidirectional causality, respectively. The connectedness approach indicates that the crude oil market affects financial stress through investors’ risk preferences.

Research limitations/implications

The Diebold–Yilmaz spillover index model is based on vector autoregression methods with a stationarity precondition. However, some of the five dimensions that constitute the financial stress index (FSI) are nonstationary in level. Therefore, the authors takes the first difference of the nonstationary data.

Practical implications

The linkage between the crude oil market and the FSI provides useful information for investors and policymakers. For instance, this paper indicates that an investor wanted to forecast future value of the crude oil (financial stress) should consider the current and past values of financial stress (crude oil). Moreover, policymaker should consider the crude oil market (FSI) to make a policy proposal for financial system (crude oil market).

Originality/value

Recently, indicators of economic activity levels (economic policy uncertainty, implied volatility index) have begun to be considered to analyze the relationship between energy and the economy but very little is known in the literature about the leading and lagging roles of data in subsample periods and the linkage channel. The other originality of this research is using the new econometric approaches.

Details

Studies in Economics and Finance, vol. 41 no. 4
Type: Research Article
ISSN: 1086-7376

Keywords

Article
Publication date: 2 August 2024

Sweta, RamReddy Chetteti and Pranitha Janapatla

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Originality/value

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.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 34 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 14 December 2023

Durrey Shahwar and Rajib Lochan Dhar

The current digital work environment promoting a “constant-on” culture is a hotbed for cyber incivility. Thus, there is a pressing need to understand its mechanisms. This study…

Abstract

Purpose

The current digital work environment promoting a “constant-on” culture is a hotbed for cyber incivility. Thus, there is a pressing need to understand its mechanisms. This study aims to shed light on the triggers, sources and impact of rude behaviours in cyberspace. The authors also present the boundary conditions that exacerbate or alleviate the effects of such negative experiences.

Design/methodology/approach

Through a systematic literature review based on predefined search protocols, the authors synthesised the current knowledge on cyber incivility and identified 21 peer-reviewed research articles.

Findings

The findings reveal the different sources of cyber incivility, its personal, relational and organisational antecedents and consequences, and its personal and situational boundary conditions that curb or enhance the negative impact.

Research limitations/implications

The authors unravel the main future research avenues based on the review findings by systemising knowledge on cyber incivility. Managerial efforts in the form of interventions and mitigation are also discussed to help combat this grieving issue in the workplace.

Originality/value

This paper presents the first systematic review of the cyber incivility literature and identifies new avenues for future research. Scholars can expand upon the findings of this study to fill gaps and move the incivility in cyberspace forward. It also offers practical insights on mitigating the advancement of such behaviours in organisations.

Details

International Journal of Conflict Management, vol. 35 no. 4
Type: Research Article
ISSN: 1044-4068

Keywords

Article
Publication date: 24 July 2024

Biswajit Paul, Raktim Ghosh, Ashish Kumar Sana, Bhaskar Bagchi, Priyajit Kumar Ghosh and Swarup Saha

This study empirically investigates the interdependency of select Asian emerging economies along with the financial stress index during the times of the global financial crisis…

Abstract

Purpose

This study empirically investigates the interdependency of select Asian emerging economies along with the financial stress index during the times of the global financial crisis, the Euro crisis and the COVID-19 period. Moreover, it inspects the long-memory effects of the different crises during the study period.

Design/methodology/approach

To address the objectives of the study, the authors apply different statistical tools, namely the adjusted correlation coefficient, fractionally integrated generalised autoregressive conditional heteroskedasticity (FIGARCH) model and wavelet coherence model, along with descriptive statistics.

Findings

Financial stress is having a prodigious effect on the economic growth of select economies. From the data analysis, it is found that the long-memory effect is noted in the gross domestic product (GDP) for India and Korea only, which implies that the volatility in the GDP series for these two nations demonstrates persistence and dependency on previous values over a lengthy period.

Originality/value

The study is unique of its kind to consider multi-segments within the period of the study to get a clear idea about the effects of the financial stress index on select Asian emerging economies by applying different econometric tools.

Details

Journal of Economic and Administrative Sciences, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2054-6238

Keywords

Book part
Publication date: 6 September 2024

Alyssa Birnbaum and M. Gloria González-Morales

There are often relational interactions in teams that lead to and drive the spread of work engagement. Despite the potential social impacts on work engagement, such as coworker…

Abstract

There are often relational interactions in teams that lead to and drive the spread of work engagement. Despite the potential social impacts on work engagement, such as coworker support and organizational citizenship behaviors within teams, they have rarely been studied from a social perspective using social network analysis (SNA). This review draws on the crossover model and conservation of resources theory to suggest that the effects of social diffusion and the exchange of resources can impact Well-Being, specifically work engagement, in teams and that SNA can help measure those social interactions. Linking several network concepts – closeness centrality, density, degree centrality, and tie strength – to work engagement propositions related to the spread of work engagement as well as the number and quality of network ties, this review elucidates the potential for integrating SNA methodology to the field of Well-Being for teams.

Details

Stress and Well-Being in Teams
Type: Book
ISBN: 978-1-83797-731-4

Keywords

Open Access
Article
Publication date: 16 July 2024

Mohammed Y. Fattah, Qutaiba G. Majeed and Hassan H. Joni

The experiments of this study investigated the effect of the subgrade degree of saturation on the value of the stresses generated on the surface and the middle (vertical and…

Abstract

Purpose

The experiments of this study investigated the effect of the subgrade degree of saturation on the value of the stresses generated on the surface and the middle (vertical and lateral stresses). The objectives of this study can be identified by studying the effect of subgrade layer degree of saturation variation, load amplitude and load frequency on the transmitted stresses through the ballast layer to the subgrade layer and the stress distribution inside it and investigating the excess pore water pressure development in the clay layer in the case of a fully saturated subgrade layer and the change in matric suction in the case of an unsaturated subgrade layer.

Design/methodology/approach

Thirty-six laboratory experiments were conducted using approximately half-scale replicas of real railways, with an iron box measuring 1.5 x 1.0 × 1.0 m. Inside the box, a 0.5 m thick layer of clay soil representing the base layer was built. Above it is a 0.2 m thick ballast layer made of crushed stone, and on top of that is a 0.8 m long rail line supported by three 0.9 m (0.1 × 0.1 m) slipper beams. The subgrade layer has been built at the following various saturation levels: 100, 80, 70 and 60%. Experiments were conducted with various frequencies of 1, 2 and 4 Hz with load amplitudes of 15, 25 and 35 kN.

Findings

The results of the study demonstrated that as the subgrade degree of saturation decreased from 100 to 60%, the ratio of stress in the lateral direction to stress in the vertical direction generated in the middle of the subgrade layer decreased as well. On average, this ratio changed from approximately 0.75 to approximately 0.65.

Originality/value

The study discovered that as the test proceeded and the number of cycles increased, the value of negative water pressure (matric suction) in the case of unsaturated subgrade soils declined. The frequency of loads had no bearing on the ratio of decline in matric suction values, which was greater under a larger load amplitude than a lower one. As the test progressed (as the number of cycles increased), the matric suction dropped. For larger load amplitudes, there is a greater shift in matric suction. The change in matric suction is greater at higher saturation levels than it is at lower saturation levels. Furthermore, it is seen that the load frequency value has no bearing on how the matric suction changes. For all load frequencies and subgrade layer saturation levels, the track panel settlement rises with the load amplitude. Higher load frequency and saturation levels have a greater impact.

Details

Railway Sciences, vol. 3 no. 4
Type: Research Article
ISSN: 2755-0907

Keywords

Article
Publication date: 11 July 2024

Hendy Abdualla Ahmed, Ismail Osman and Heba Mari

Objective is to investigate the effects of COVID-19 on the performance and productivity of infodemic research. A comprehensive bibliometric analysis is conducted using data…

Abstract

Purpose

Objective is to investigate the effects of COVID-19 on the performance and productivity of infodemic research. A comprehensive bibliometric analysis is conducted using data extracted from Thomson Reuters' Web of Science, and the analysis is facilitated by the bibliometrix and biblioshiny tools.

Design/methodology/approach

Data was extracted from the Web of Science (WoS) database provided by Thomson Reuters. Therefore, literature published outside of the WoS database was not included. Results were extracted about the Document Type, Research Area, Language, Publication year, and country or countries for all authors because this study was interested in scholarly international collaboration. The researcher also used the Thomson Reuters Web of Science’s InCites Essential Science Indicators database, which allowed the researcher to measure the scientific output performance of countries over a period of time. In addition to InCites data, citation data and international collaboration for all countries were also downloaded.

Findings

Inclusion and exclusion criteriax: this study focused on literature published by authors identified by each author’s affiliation in each publication. Thus, the WoS topic field was searched by “infodemic” or “information epidemic” or “info ebidemic”. The time span selected for this study started from 2018 to 2022, allowing the researcher to survey the nature of the literature during the last 6 years before COVID-19 and 4 years after COVID-19 to identify the effects of COVID-19 on research in the world regarding both performance and productivity. The study included various types of materials, such as articles, early access, and review articles.

Originality/value

A comprehensive bibliometric analysis is conducted using data extracted from Thomson Reuters' Web of Science, and the analysis is facilitated by the bibliometrix and biblioshiny tools. The findings reveal that prior to the COVID-19 outbreak, researchers contributed a total of 3,960 documents, with the United States leading with 2,933 publications, followed by China with 2,561. However, the production of infodemic research doubled following the onset of the pandemic, resulting in a total of 6,979 documents. Both before and after COVID-19.

Details

Library Hi Tech, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0737-8831

Keywords

Article
Publication date: 16 September 2024

Yi-Chia Wang and Hong-Lin Su

This study aims to investigate the dynamics between exogenous shocks, financial stress and economic performance in the USA from January 1995 to August 2023.

Abstract

Purpose

This study aims to investigate the dynamics between exogenous shocks, financial stress and economic performance in the USA from January 1995 to August 2023.

Design/methodology/approach

Granger-causality tests and impulse response analyses are used to examine causal relationships and dynamic responses among crude oil prices, real M2 money supply, financial stress and key economic indicators.

Findings

This study reveals a significant correlation between elevated financial stress and reduced real output, along with disruptions in the labor market, potentially leading to economic recessionary trends. Failure to address these challenges could perpetuate labor market difficulties, weaken capital accumulation within the loanable funds market and ultimately hinder long-term economic growth prospects in the USA.

Practical implications

This study offers insights for policymakers to mitigate financial stress. Recommendations include enhancing financial surveillance, strengthening regulatory frameworks, promoting economic diversification and implementing countercyclical policies to stabilize the economy and support labor markets. In addition, proactive monitoring of financial stress indicators can serve as early warning signals, aiding in timely interventions and effective risk management strategies.

Originality/value

This research provides a comprehensive analysis of how the financial stress index (FSI) mediates the effects of external shocks on the US economy, addressing a gap in existing literature. The integration of the FSI into the analysis enhances the understanding of the transmission channels through which external shocks influence the economy.

Details

Studies in Economics and Finance, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1086-7376

Keywords

Article
Publication date: 3 April 2023

Kip Errett Patterson

This conceptual article presents a schematic of rat maternal behavior and niche stress epigenetic effects as a case study that is then aligned with current evolutionary concepts…

Abstract

Purpose

This conceptual article presents a schematic of rat maternal behavior and niche stress epigenetic effects as a case study that is then aligned with current evolutionary concepts, which raises new questions regarding immigrant assimilation and niche dynamics.

Design/methodology/approach

The necessary background material for rat maternal and niche(s) stress factors are incorporated into a recursive, test-operate-test (rTOT), information-only-transfer, schematic (Patterson, 2023), which is an extension and refinement of the test-operate-test-exit (TOTE) schematic of Miller et al. (1960).

Findings

The generated epigenetic rTOT demonstrates the fundamental evolutionary unit of the flexible organism within its niche(s). The rTOT also confirms that epigenetic processes, epigenetic inheritance and phenotype plasticity are significant conceptual tools for understanding evolution. The teleology of rat adaptations for niche fitness via maternal behavior has been demonstrated. Sterling's (2011) allostasis, or predictive homeostasis, is extended to include species-niche(s) interaction(s) that are governed by recursive information feedback loops that function via self-organized criticality (SOC) for species and niche(s). Use of a rat model for biosocial issues in humans is strengthened.

Research limitations/implications

Epigenetic rTOT only covers the species side of the evolutionary unit. Niche(s) require(s) a separate rTOT schematic. The information modeled does not include the entire system producing epigenetic effects but models a substantial portion of it.

Practical implications

Epigenetic rTOT demonstrates the utility of phenotypic plasticity, epigenetics and epigenetic inheritance as explanations for inheritable behavior patterns. rTOT is a useful computational model for evolutionary issues. The issues involved in niche modeling using an rTOT schematic are briefly reviewed.

Social implications

When the demonstrated epigenetic model of rat genetics and inherited behavior are applied to the issues of immigrant enclaves, epigenetic complications for the difficulties of assimilation into the culture within which the enclaves are embedded become apparent. However, the questions raised must be addressed with extreme care to avoid cultural imperialism. Such cultural issues must be modeled with an rTOT application that covers the materials involved. The limitations of human Learning III restrictions when attempting to model Learning IV issues are addressed. Research into the means by which abuse and trauma are maintained by epigenetic means is urgently needed.

Originality/value

The rTOT schematic visualizes rat maternal behavior and stress epigenetic effects that produce inheritable behavior patterns, which answers Jablonka's (2017) request for new computational modeling representations. The concept of allostasis, or predictive homeostasis, (Sterling, 2011) is extended to the niche(s) of the organism under study so that allostasis becomes a fully cybernetic concept governed by SOC for both the organism and its niche(s). This new case study confirmed evolutionary effects of epigenetics, epigenetic inheritance and phenotypic plasticity. Niche control of organism evolution is presented. Epigenetic applications for immigrant assimilation issues have been suggested and niche dynamic questions have been raised.

Details

Kybernetes, vol. 53 no. 8
Type: Research Article
ISSN: 0368-492X

Keywords

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