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Liquid-assisted laser surface texturing technology was used to create composite microtextures on triangular guide rail surfaces to enhance their tribological properties.

Numerical simulations were used to investigate the impact of various microtextures on fluid dynamic lubrication. Reciprocating friction and wear tests, followed by mechanistic analysis, examined the combined tribological effects of microtextured surfaces and lubricants.

The numerical simulation outcomes reveal a significant augmentation in the influence of fluid dynamic pressure due to composite microtextures, consequently amplifying the load-bearing capacity of the oil film. The average friction coefficient of composite microtextured samples was approximately 0.136 in reciprocating pin-on-disk friction tests, representing approximately 17% decrease compared to polished samples. Triangular guide rails with composite microtextures demonstrated the lowest average coefficient under conditions of high-speed and heavy-loading in the reciprocating friction and wear tests. Additionally, the presence of composite microtextures was found to promote the formation of adsorbed and friction films during friction, potentially contributing to the enhancement of tribological properties.

Triangular guide rails face high friction and wear, limiting their stability in demanding applications like machine tool guideways. This paper proposes a novel approach for steel triangular guide rails, involving composite microtexturing, numerical fluid simulations, liquid-assisted laser surface texturing and friction-wear testing. By implementing composite microtextures, the method aims to reduce friction coefficients and extend guideway service life, thereby saving energy and reducing maintenance costs. Enhancing the antifriction and antiwear properties of machine tool guideways is crucial for improving performance and longevity.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0183/

Through this research study, the authors found that digital thread has made significant progress in the life cycle management of the US Air Force. The authors hope that by reviewing similar studies in the aerospace field, the meaning of digital thread can be summarized and applied to a wider range of fields. In addition, theoretically, the definition of digital twin and digital thread are not unified. The authors hope that the comparison of digital thread and digital twin will better enable scholars to distinguish between the two concepts. Besides, the authors are also looking forward that more people will realize the significance of digital thread and carry out future research.

Complete research about digital thread and the relevant concept of the digital twin is conducted. First, by searching in Google Scholar with the keyword “digital thread”, the authors filter results and save literature with high relevance to digital thread. The authors also track these papers’ references for more paper of digital thread and digital twin. After removing the duplicate and low-relevance literature, 72 digital thread-related literature studies are saved and further analyzed from the perspective of time development, application field and research directions.

Digital thread application in industries other than the aviation manufacturing industry is still relatively few, and the research on the application of digital thread in real industrial scenarios is mainly at the stage of framework design and design-side decision optimization. In addition, the digital thread needs a new management mechanism and organizational structure to realize landing. The new management mechanism and the process can adapt to the whole life cycle management process based on the digital thread, manage the data security and data update, and promote the digital thread to play a better effect on the organizational management.

Based on a review of digital thread, future research directions and usage suggestions are given. The fault diagnosis of high-speed train bogie as an example shows the effectiveness of the method and also partially demonstrates the advantages and effects brought by the digital thread connecting the data models at various stages.

This paper first investigates and analyzes the theoretical connotation and research progress of digital thread and gives a complete definition of digital thread from the perspective of the combination of digital thread and digital twins. Next, the research process of digital thread is reviewed, and the application fields, research directions and achievements in recent years are summarized. Finally, taking the fault diagnosis of high-speed train bogie as an example partially demonstrates the advantages and effects brought by the digital thread connecting the data models at various stages.

This paper aims to investigate the impact of board characteristics on CEO turnover performance relationship (TPR) in Indian listed firms.

A subset of the Standard and Poor’s Bombay Stock Exchange 500 (S&P BSE 500) Index companies was analyzed over the period 2015–2019 using the logistic (fixed-effects) regression model.

It was found that a weak relationship exists between CEO turnover and firm performance. With respect to board characteristics, board size was found to have a significant role in strengthening the TPR. However, other characteristics, such as board independence, multiple directors, board meetings and board gender diversity, played no role in influencing the TPR.

First, the study period is limited to five years, during which several sample firms did not face any CEO turnover event leading to small sample size. Second, this study considers only the board’s gender diversity, whereas other types of diversity are omitted. Third, this study does not differentiate between insider and professional CEOs.

The findings suggest that regulators should focus on the effective enforcement of laws to strengthen the TPR and improve the monitoring role of boards, particularly in emerging economies like India, which face type II agency problems in addition to traditional principal–agent conflict. The results also offer implications for corporations, investors and academic researchers, highlighting areas that need considerable attention pertaining to corporate governance.

This study discerns the impact of several board-related characteristics on the TPR, particularly after the introduction of the new Companies Act 2013 in the emerging economy of India, where it has not been explored extensively.

Independent directors (IDs) in India are required to qualify for the online proficiency self-assessment test to acquire or retain their position on the corporate boards. The purpose of this paper was to examine the perceived positive and negative aspects of the new mandate for the overall quality of corporate boards in India.

This study used a qualitative methodology and applied the interpretative phenomenological analysis approach. Data was collected from board members using semi-structured interviews.

This study revealed the positive and negative perceived aspects of the mandatory policy prescription of proficiency test for IDs. It was found that the participants emphasized training and mentoring programs for the IDs.

Drawing upon the actual board experiences of the participants, this study has the potential to assist policymakers in making regulations that are more effective in enhancing the quality of corporate boards. The example of action taken as well as the criticism or positive aspects pointed out can generate interest in other legislators.

The concept of proficiency test for IDs is unique to India. A review of literature did not reveal the existence of any regulatory provisions for a mandatory uniform test for examining the proficiency of IDs, in any corporate law jurisdiction apart from India.

This study aims to examine the relationship between board capital and firm performance in the Chinese tourism industry.

The study’s sample includes firms from the Chinese hotel, air transportation/travel and catering industries. This study explores the governance environment in tourism industries. This study estimates three dimensions of the board, including education, expertise and directors interlock. These dimensions are further grouped as human capital (i.e. education and expertise), social capital (interlocks) and board capital (sum of social and human capital). Ordinary least square regressions with multiple robustness tests are used to investigate the effect of board capital on firm value in Chinese listed tourism firms during 2005–2018.

This study finds that board capital positively impacts firm performance in its dimensions of human and social capital. This study also highlights the two important ownership contexts, namely, institutional investors and state-ownership, that shape the board capital-firm performance association in the Chinese tourism industry.

The findings suggest that board capital plays a significant role in corporate decisions. The results illustrate that higher board capital improves both governance mechanisms and resource provision roles of the board, resulting in higher firm value. The results further offer implications for managers and shareholders of tourism firms when electing directors as shareholders’ representatives.

The study has two important contributions. First, it extends the prior literature of firm value by considering the board’s human and social dimensions in the tourism sector. Second, contrary to prior research on board, this study takes three facets of board capital, education, expertise and interlocks that improve governance mechanisms and bring new resources in the shape of skills, knowledge and expertise.

The purpose of this study is to examine the impact of corporate governance (CG) on chief executive officer compensation (CEO COMP) and pay–performance relationship (PPR) in Indian listed firms.

A sample of 196 companies listed on the S&P BSE 500 (Standard and Poor's Bombay Stock Exchange 500) Index has been analyzed using the panel (random effects) regression technique over the period 2010–2019. In addition, the system GMM technique was used to deal with the endogeneity issue.

The study found that block ownership and ownership concentration negatively impact COMP measures and PPR. Board size also had a negative direct and moderating impact on CEO COMP; however, the linkages were generally insignificant, especially for total pay. Similarly, outsider blockholders were found to be playing an insignificant role. Further, board independence positively influences COMP levels and PPR, though the results were mixed with respect to significance. Finally, CEO duality positively and significantly influences CEO COMP and PPR. A comparison before and after the new Indian Companies Act 2013 also revealed similar results, particularly in the after period. It suggests that the new legislative initiative was not effective enough in improving the CG and, hence, the alignment of pay with performance.

This study investigates the direct and moderating impact of CG on CEO COMP in the context of emerging economy India. Further, it makes a comparison before and after the introduction of the new governance reform, that is, the Indian Companies Act, 2013. Moreover, providing support to the entrenchment effect, the study reveals that large shareholders expropriate minority shareholders’ wealth by not aligning CEO pay with performance, making agency problems graver in emerging economies like India.

With the rapid increase in the number of installed wind turbines (WTs) worldwide, requirements and expenses of maintenance have also increased significantly. The condition monitoring (CM) of WT provides a strong “soft guarantee” for preventive maintenance. The supervisory control and data acquisition (SCADA) system records a huge amount of condition data, which has become an effective means of CM. The main objective of the present study is to summarize the application of SCADA data to fault detection in wind turbines, analyze its advantages and disadvantages and predict the potential of future investigations on the use of SCADA data for fault detection.

The authors first review the means of WT CM and summarize the characteristics of CM based on SCADA data. To ensure the quality of SCADA data, data preprocessing methods are analyzed and compared. Then, the failure modes of the key components are discussed and the SCADA data used for fault detection of each component are compared. Moreover, the fault detection methods for WT are classified and a general framework for fault detection is proposed. Finally, the issues in the WT fault detection method based on SCADA data are reviewed.

Based on the performed analyses, it is found that although the fault detection accuracy based on SCADA data is relatively poor, it has low capital expenses and low computational cost. More specifically, when there is scarce fault data, the normal SCADA data can be used to detect the fault time. However, the specific fault type cannot be identified in this way. When a large amount of fault data are accumulated in the SCADA system, it can not only detect the occurrence time of the fault but also identify the specific fault type.

The main contribution of the present study is to summarize the pre-processing methods for SCADA data, the data required for fault detection of key components and the characteristics of the fault detection model. Then we propose a general fault detection framework for wind turbines based on SCADA data, where the maintenance workers can choose the appropriate fault detection method according to different fault detection requirements and data resources. This article is expected to provide guidance for fault detection based on time-series sensor signals and be of interest to researchers, maintenance workers and managers.

This study intends to review studies on the success criteria and critical success factors (CSFs) for mega infrastructure construction projects (MICPs) from journal articles between 2000 and 2018 to (1) identify the publication trend of success criteria and CSFs for MICPs; (2) explore distributions of selected papers, including the distribution of journals, authors’ origin/country and publications by country or region focus; and (3) summarize the findings of success criteria and CSFs studies of MICPs.

A methodical and systematic analysis of 38 selected journal articles was conducted using descriptive analysis to obtain the annual trend of publications, distributions of publication sources, contributors’ origin/country, regions/countries of research focus, methods involved in publications and thematic analysis to identify and categorize success criteria and CSFs for MICPs.

Australia, the USA, UK, China and Hong Kong had been the leading contributors for publications on success criteria and CSFs for MICPs; meanwhile, China, Australia and the UK have been the countries of focus for most studies on this specific topic. This review identified 20 success criteria grouped into 5 constructs and 36 CSFs grouped into 5 categories and, respectively, integrated them into two conceptual frameworks. The top five CSFs were adequate resource availability, partnering/relationships with key stakeholders, adequate communication and coordination among related parties, public support or acceptance and clear strategic vision. Three implications, namely, evaluation indicators, relationships between CSFs and the success of MICPs and human-related factors, are highlighted in future research.

The identified success criteria and CSFs provide a basis for evaluating the success possibility of MICPs and serve to identify areas for further improvement. Additionally, the CSFs checklist and framework have been established, which could help to conduct further empirical studies. Finally, the holistic analysis identifies gaps in the body of knowledge, revealing avenues for future research.

At the present time, green cutting has become the focus of attention in ecological and environmental protection. Water vapor is cheap, pollution‐free and eco‐friendly. Therefore, it is a good and economical coolant and lubricant. To find the discipline of nozzle diameter, the parameters of water vapor jet flow and cooling distance influence on its lubricating action effect, experiments were carried out in which YT15 (P10 type in ISO) tool was used in cutting C45 steel.

The vapor generator and vapor feed system are manufactured. The temperature and velocity distribution of water vapor jet flow influences the velocity such that water vapor fills up the capillaries and forms the boundary lubricating film layer in the cutting zone, and the temperature and velocity distribution of the vapor jet flow section contains the effective area for the lubricating effect. Through the temperature distribution measured, the empirical formula of temperature distribution is obtained and simulated by Matlab. The turning experiment was carried out according to quantity in cutting υ_c=45, 60, 75, 90, 105, 120 mm/min, f=0.1 ∼ 0.3 mm/rev, a_p=1, 2, 3, 3.5 mm and the jet flow parameters were changed, respectively.

It was found that: significant decrease of cutting force can be realized with reduced nozzle diameter, increased the sett pressure and shortened the cooling distance. However, reduced to a certain extent it will lead to the increase of the cutting force. The optimal nozzle diameter is 2 mm for the best lubricating effect. The effect on cutting force of the cooling distance is much better than the setting pressure. Significant decrease of friction coefficient of tool‐chip can be realized with reduced nozzle diameter. However, reduced to a certain extent it will lead to the increase of friction coefficient. Significant thinness of chips can be realized by reducing nozzle diameter. But if the diameter is reduced to a certain degree, chips will be thickened. Increased set pressure and shortened cooling distance can both reduce chip thickness, resulting in reduction of chip deformation coefficient. Since water vapor has the advantage of being cheap, pollution‐free and harmless, and there is no need for disposal and recycling, it is ideal for cooling and lubricating technology in green cutting.

The paper establishes the discipline of nozzle diameter, the parameters of water vapor jet flow and cooling distance influence on its lubricating action effect.

This study aims to analyze the impact of corporate governance on firms’ external financing decisions in the Middle East and North Africa (MENA) region.

The authors analyzed a unique set of panel data comprising 2,425 nonfinancial firms whose shares are traded on stock exchanges in countries in the MENA region. The authors fitted an ordinary least squares model to estimate the regression coefficients. The authors performed a sensitivity analysis using alternative measures of the critical variables and an endogeneity analysis using instrumental variable methods with plausible external instruments.

The results revealed that corporate governance characteristics of firms are strongly associated with their degree of leverage. They also showed that macrofinancial conditions, financial regulations, corporate governance enforcement and social conditions mitigate the impact of corporate governance on firms’ financing decisions.

A larger sample size will further improve the results; however, this is difficult and depends on the extent to which increasing disclosure practices allow more corporate information to reach international databases.

This study provides new evidence on the role of corporate governance on firms’ financing decisions and documents the essential mitigating role of institutions, alerting managers to consider them.

This study is a novel attempt. Based on information from different data sources, this study explored the predictive power of corporate governance, ownership structures and other firm-specific characteristics in explaining corporate leverage in MENA countries. Overall, the analysis provides new evidence of the association between corporate governance and capital structure in the MENA region, highlighting the critical role of institutions.