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This study aims to investigate the rarefaction effects on flow and thermal performances of an equivalent sand-grain roughness model for aerodynamic thrust bearing.

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.

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.

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.

To further promote application of BIM technology in construction of prefabricated buildings, influencing factors and evolution laws of willingness to apply BIM technology are explored from the perspective of willingness of participants.

In this paper, a tripartite game model involving the design firm, component manufacturer and construction firm is constructed and a system dynamics method is used to explore the influencing factors and game evolution path of three parties' application of BIM technology, from three perspectives, cost, benefit and risk.

The government should formulate measures for promoting the application of BIM according to different BIM application willingness of the parties. When pursuing deeper BIM application, the design firm should pay attention to reducing the speculative benefits of the component manufacturer and the construction firm. The design firm and the component manufacturer should pay attention to balancing the cost and benefit of the design firm while enhancing collaborative efforts. When the component manufacturer and the construction firm cooperate closely, it is necessary to pay attention to balanced distribution of interests of both parties and lower the risk of BIM application.

This study fills a research gap by comprehensively investigating the influencing factors and game evolution paths of willingness of the three parties to apply BIM technology to prefabricated buildings. The research helps to effectively improve the building quality and construction efficiency, and is expected to contribute to the sustainability of built environment in the context of circular economy in China.

The purpose of this study is to explore the interfacial adhesion between superhydrophobic coatings FC-X (X = 1%, 2%, 3%, 4% and 5%) and the concrete substrate, along with the impact of FC-X on the water repellency characteristics of the concrete substrate.

One synthetic step was adopted to prepare novel F-SiO₂ NP hybrid fluororesin coating. The impact of varying mass fractions of F-SiO₂ NPs on the superhydrophobicity of FC-X was analyzed and subsequently confirmed through water contact angle (WCA) measurements. Superhydrophobic coatings were simply applied to the concrete substrate using a one-step spraying method. The interfacial adhesion between FC-X and the concrete substrate was analyzed using tape pasting tests and abrasion resistance measurements. The influence of FC-X on the water repellency of the concrete substrate was investigated through measurements of water absorption, impermeability and electric flux.

FC-4% exhibits excellent superhydrophobicity, with a WCA of 157.5° and a sliding angle of 2.3°. Compared to control sample, FC-X exhibits better properties, including chemical durability, wear resistance, adhesion strength, abrasion resistance, water resistance and impermeability.

This study offers a thorough investigation into the practical implications of enhancing the durability and water repellency of concrete substrates by using superhydrophobic coatings, particularly FC-4%, which demonstrates exceptional superhydrophobicity alongside remarkable chemical durability, wear resistance, adhesion strength, abrasion resistance, water resistance and impermeability.

Through the examination of the interfacial adhesion between FC-X and the concrete substrate, along with an assessment of FC-X’s impact on the water repellency of the concrete, this paper provides valuable insights into the practical application of superhydrophobic coatings in enhancing the durability and performance of concrete materials.

With the rapid development of Internet technology, cybersecurity threats such as security loopholes, data leaks, network fraud, and ransomware have become increasingly prominent, and organized and purposeful cyberattacks have increased, posing more challenges to cybersecurity protection. Therefore, reliable network risk assessment methods and effective network security protection schemes are urgently needed.

Based on the dynamic behavior patterns of attackers and defenders, a Bayesian network attack graph is constructed, and a multitarget risk dynamic assessment model is proposed based on network availability, network utilization impact and vulnerability attack possibility. Then, the self-organizing multiobjective evolutionary algorithm based on grey wolf optimization is proposed. And the authors use this algorithm to solve the multiobjective risk assessment model, and a variety of different attack strategies are obtained.

The experimental results demonstrate that the method yields 29 distinct attack strategies, and then attacker's preferences can be obtained according to these attack strategies. Furthermore, the method efficiently addresses the security assessment problem involving multiple decision variables, thereby providing constructive guidance for the construction of security network, security reinforcement and active defense.

A method for network risk assessment methods is given. And this study proposed a multiobjective risk dynamic assessment model based on network availability, network utilization impact and the possibility of vulnerability attacks. The example demonstrates the effectiveness of the method in addressing network security risks.

Over the years, the impact of personality attributes on work behavior has constituted a broad research domain. The manner in which employees view themselves have been regarded as significant in analyzing their work behavior and eventual employee performance from the organizational perspective. The purpose of this paper is to investigate the relationship between self-concept and performance, with resilience as a mediator and Machiavellianism as a moderating variable.

Data were collected from 271 employees from four medium-sized private sector companies in India after excluding missing data. Correlation, regression and Hayes Macro analysis were conducted to test the hypotheses.

Resilience mediates the relationship between self-concept and performance. Second, Machiavellianism moderated the relationship between self-concept and resilience and moderated the mediation effect of resilience on the relationship between self-concept and performance. The role of personality attributes has been found to profoundly impact the employee's perception of self and work performance. Resilience, which refers to the individual's ability to bounce back amidst adverse situations, is simultaneously moderated by one of the dark triad personalities, Machiavellianism.

Understanding the self-concept dimension, the dual effects of resilience and the Machiavellianism personality have gradually become immensely significant for improvising employee work performance in the organization.

This original research has examined a model of untested variables and explored the mediating effect of resilience by connecting self-concept to performance along with the moderated-mediated impact of Machiavellianism on the variables, which is a novel attempt.

This study aims to investigate the logic between digital transformation and export performance by analysing a large sample of Vietnamese exporters. The theoretical model is further extended by investigating the driving role of digital transformational leadership and mediating effects of firm digital capabilities and employee exploration and exploitation innovation.

The study sample comprised 364 middle managers at 107 export firms in Ho Chi Minh City, Vietnam. The data are analysed using a partial least square-structural equation model (PLS-SEM).

Digital transformation may be an indispensable tool for enhancing the export performance of businesses. Moreover, digital transformational leadership may drive digital transformation through the mediating mechanisms of firm digital capabilities and employee exploration and exploitation innovations to achieve high export performance.

This initial study contributes significantly to international business theory through the lens of dynamic capabilities theory, which reveals the role of digital transformation in export performance via mechanisms of digital transformational leadership, firm digital capabilities and employee exploration and exploitation innovation.

Geopolitical risks (GPR) and increase in equity market volatility due to health pandemics have great implications on assets prices around the world. Many empirical studies have focused on the effects of these risks on different financial assets. The purpose of this paper is to contribute to this related literature by examining the dynamic effects of GPRs and infectious diseases–induced equity market volatility on regional and global house price indexes.

This paper explores the asymmetric effects of infectious diseases and GPRs on house prices across different market conditions using the quantile regression approach. This technique enables us to examine the nonlinear asymmetric effects of GPRs and infectious diseases on both global and regional house price indexes using daily data from January 1, 2011, to June 3, 2022. It focuses on both the effects of a composite measure of GPR as well as the disaggregated effects of threats and acts (war) on the real estate markets under different market conditions.

The main findings of this study demonstrates that the effects of geopolitical and infectious diseases–related risks vary differently across regional real estate markets and the nature of the GPR. In particular, the effects of geopolitical threats are stronger than those of geopolitical acts, especially for the European, Asia-Pacific and North American regions during bullish market periods. Except for the effects of geopolitical threats during real estate market downturns, the African real estate market appears to be insulated from the effects of GPRs across all market conditions. Also, the authors show that infectious diseases increase losses in real estate investments when the market condition is bearish for all markets and could extend toward the normal market period for the North American, Asia-Pacific and European markets. However, across all the market conditions, the effects of the composite index of GPRs are not significant for the Asia-Pacific and European regional markets. Results are mixed for the remaining markets, especially for the global market. Whereas during bearish market periods, the effect is positive, it becomes negative when the market condition become normal and insignificant when it becomes bullish. For the North American and African regional markets, the effect is positive under the bearish market state.

Increase in equity market volatility due to infectious diseases as well as conflicts and tensions among major powers, including potential risks of financial instability, all lead to significant increase in shocks to financial markets. To the best of the authors’ knowledge, this is the first study to analyze the asymmetric and comparative effects of GPRs and infectious diseases–related equity market volatility on real estate investments across different regions and market conditions. Because of the complexity of these risks and policy shifts, and the characteristics and heterogeneity of different regional financial markets, the impacts of shock from these risks are intuitively diverse, with practical implications for portfolio management.

This paper aims to propose a new method to derive custom dynamic cyber risk metrics based on the well-known Goal, Question, Metric (GQM) approach. A framework that complements it and makes it much easier to use has been proposed too. Both, the method and the framework, have been validated within two challenging application domains: continuous risk assessment within a smart farm and risk-based adaptive security to reconfigure a Web application firewall.

The authors have identified a problem and provided motivation. They have developed their theory and engineered a new method and a framework to complement it. They have demonstrated the proposed method and framework work, validating them in two real use cases.

The GQM method, often applied within the software quality field, is a good basis for proposing a method to define new tailored cyber risk metrics that meet the requirements of current application domains. A comprehensive framework that formalises possible goals and questions translated to potential measurements can greatly facilitate the use of this method.

The proposed method enables the application of the GQM approach to cyber risk measurement. The proposed framework allows new cyber risk metrics to be inferred by choosing between suggested goals and questions and measuring the relevant elements of probability and impact. The authors’ approach demonstrates to be generic and flexible enough to allow very different organisations with heterogeneous requirements to derive tailored metrics useful for their particular risk management processes.

This study aims to explore the influence mechanism of inclusive leadership on employees' innovative behavior, in order to provide useful inspiration for leaders and enterprises to develop.

This study constructs a moderated mediation model based on the valid questionnaire data of 211 employees in service in enterprises and used SPSS23.0 and AMOS24.0 analysis software to analyze the data and test the theoretical hypotheses, and explore the influence mechanism of inclusive leadership on employees' innovative behavior.

The empirical findings show that inclusive leadership has a significant positive impact on employees' innovative behavior; organizational harmony plays a mediating role in the relationship between inclusive leadership and employees' innovative behavior; and innovation self-efficacy plays a positive moderating role between organizational harmony and employees' innovative behavior. Therefore, inclusive leadership can create a harmonious organizational climate and further improve employees' innovative behavior under the influence of employees' creative self-efficacy, which can promote innovative behavior and sustainable development of enterprises.

The authors put two variables, organizational harmony and employees' innovation self-efficacy, into the same model for correlation tests for the first time, and introduced into the mechanism of inclusive leadership's influence on employees' innovation behavior, which broadened people's understanding of organizational harmony and innovation self-efficacy and broadened the ideas for the subsequent research about the relationship between them.

The purpose of this article is to assess the extent to which environmental economic practices are recognized and implemented in developing countries, with a specific emphasis on the Nigerian construction sector.

To examine the extent of awareness and usage, a quantitative research approach was adopted with close-ended questionnaires disseminated to construction professionals in Nigeria. The collected data were subjected to analysis using various statistical techniques such as percentages, frequencies and mean scores. Furthermore, to investigate any significant differences in the respondents' opinions, the Kruskal–Wallis H-test was applied.

The study's findings indicate that the level of awareness and implementation of environmental economic practices among construction professionals in Nigeria is limited. Based on the findings of this study, a roadmap of recommendations has been proposed to promote the adoption of environmental economic practices in the Nigerian construction industry. The implementation of these recommendations can help reduce the negative impact of construction activities on the environment and public health and contribute to the development of sustainable cities, communities and societies.

The outcomes from this study can inform policy and decision-making by providing insights into the level of knowledge and awareness of environmental economic practices among construction professionals in Nigeria.

The findings from this study provide a baseline for assessing the level of knowledge and awareness of sustainable practices among construction professionals in Nigeria, which can inform future studies on the effectiveness of training and awareness programs.