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In response to the problem of insufficient traction/braking adhesion force caused by the existence of the third-body medium on the rail surface, this study aims to analyze the utilization of wheel-rail adhesion coefficient under different medium conditions and propose relevant measures for reasonable and optimized utilization of adhesion to ensure the traction/braking performance and operation safety of trains.

Based on the PLS-160 wheel-rail adhesion simulation test rig, the study investigates the variation patterns of maximum utilized adhesion characteristics on the rail surface under different conditions of small creepage and large slip. Through statistical analysis of multiple sets of experimental data, the statistical distribution patterns of maximum utilized adhesion on the rail surface are obtained, and a method for analyzing wheel-rail adhesion redundancy based on normal distribution is proposed. The study analyzes the utilization of traction/braking adhesion, as well as adhesion redundancy, for different medium under small creepage and large slip conditions. Based on these findings, relevant measures for the reasonable and optimized utilization of adhesion are derived.

When the third-body medium exists on the rail surface, the train should adopt the low-level service braking to avoid the braking skidding by extending the braking distance. Compared with the current adhesion control strategy of small creepage, adopting appropriate strategies to control the train’s adhesion coefficient near the second peak point of the adhesion coefficient-slip ratio curve in large slip can effectively improve the traction/braking adhesion redundancy and the upper limit of adhesion utilization, thereby ensuring the traction/braking performance and operation safety of the train.

Most existing studies focus on the wheel-rail adhesion coefficient values and variation patterns under different medium conditions, without considering whether the rail surface with different medium can provide sufficient traction/braking utilized adhesion coefficient for the train. Therefore, there is a risk of traction overspeeding/braking skidding. This study analyzes whether the rail surface with different medium can provide sufficient traction/braking utilized adhesion coefficient for the train and whether there is redundancy. Based on these findings, relevant measures for the reasonable and optimized utilization of adhesion are derived to further ensure operation safety of the train.

To authenticate the existence and principles of the adhesion recovery phenomenon under water pollution conditions, an innovative circumferential rail–wheel adhesion test rig was used. The study conducted extensive tests on the adhesion characteristics under large sliding conditions.

Experiments were conducted to investigate the influence of speed, axle load and slip on adhesion recovery. Based on the experimental results, the adhesion recovery transition function was re-fitted.

The study reveals that the adhesion recovery phenomenon truly exists under water conditions. The adhesion coefficient shows an increasing trend with the growth of the slip ratio. Moreover, at the current speed and axle load levels, the adhesion recovery is directly proportional to the square of the slip ratio and inversely proportional to the axle load.

The phenomenon of adhesion recovery and the formulated equations in this study can serve as an experimental and theoretical foundation for the design of braking and anti-skid control algorithms for trains.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2023-0379/

This study investigates the relationships among digital transformation, technological innovation, industry–university–research collaborations and labor income share in manufacturing firms.

The relationships are tested using an empirical method, constructing regression models, by collecting 1,240 manufacturing firms and 9,029 items listed on the A-share market in China from 2013 to 2020.

The results indicate that digital transformation has a positive effect on manufacturing companies’ labor income share. Technological innovation can mediate the effect of digital transformation on labor income share. Industry–university–research cooperation can positively moderate the promotion effect of digital transformation on labor income share but cannot moderate the mediating effect of technological innovation. Heterogeneity analysis also found that firms without service-based transformation and nonstate-owned firms are better able to increase their labor income share through digital transformation.

This study provides a new path to increase the labor income share of enterprises to achieve common prosperity, which is important for manufacturing enterprises to better transform and upgrade to achieve high-quality development.

The purpose of this study is to explore the effect of managerial ability on voluntary environmental, social and governance (ESG) disclosure and assurance. By focusing on managerial ability, this study provides a more nuanced understanding of the factors influencing a firm’s ESG disclosure and assurance practices. This study contributes to a relatively unexplored area of study regarding the role of top management in promoting ESG reporting.

This study draws on a sample of publicly listed firms from 2014 to 2019 in Taiwan and applies the data envelopment analysis method to measure managerial ability. Heckman’s (1979) two-step model is used to estimate the primary models to prevent the results from being affected by possible bias because of self-selection.

The empirical evidence suggests that managerial ability is positively related to voluntary ESG disclosure and intention to seek third-party assurance of the report. Overall, managerial ability determines whether a firm will use voluntary ESG disclosure and assurance as a corporate strategy to respond effectively to stakeholders’ needs. The findings are robust after using alternative measures of managerial ability.

Investors and other stakeholders keen on seeking ESG information offered by companies could find the findings of this study valuable. By better comprehending how managerial competence impacts voluntary ESG disclosure and assurance, stakeholders may be better equipped to hold companies responsible for their ESG disclosure practices and make informed investment decisions.

In the ESG decision-making process, managers with better abilities have a higher tendency to use voluntary disclosure and assurance as a part of the company’s sustainable policy.

Unlike previous studies of the determinant factors of ESG disclosure, which mainly explore factors at the national or corporate level, this study focuses on factors at the individual level (i.e. managerial ability) to fill the gap in the literature. This study also presents empirical evidence that corroborates the idea that managerial competence can influence not only ESG disclosure but also the voluntary assurance of ESG information.

This study aims to clarify the relationship between the coefficient of friction (COF) and temperature of aluminum-based brake discs.

Three friction blocks with different COFs are examined by a TM-I-type reduced-scale inertial braking dynamometer. On this basis, the thermo-mechanically coupled model of friction pairs is established to study the evolution of brake disc temperature under different COFs using ADINA software.

Results indicate that the calculated disc temperature field matches the experimental well. The effect of COF on the peak temperature is magnified by the braking speed. With the COF increasing, the rise rate of instantaneous peak temperature is accelerated, and the dynamic equilibrium period and cooling-down period are observed in advance. The increase in COF promotes the area ratio of the high-temperature zone and the maximum radial temperature difference. When the COF is increased from 0.245 to 0.359 and 0.434 at 140 km/h, the area ratio of high-temperature zone increases from 12% to 44% and 49% and the maximum radial temperature difference increases from 56°C to 75°C and 83°C. The sensitiveness of the axial temperature difference to the COF is related to the braking time. The maximum axial temperature difference increases with COF in the early stages of braking, while it is hardly sensitive to the COF in the later stages of braking.

The effect of COF on the aluminum-based brake disc temperature is revealed, providing a theoretical reference for the popularization of aluminum-based brake discs and the selection of matching brake pads.

This study aims to realize efficient, fast and safe robot search task, the belief criteria decision-making approach is proposed to solve the object search task with an uncertain location.

The study formulates the robot search task as a partially observable Markov decision process, uses the semantic information to evaluate the belief state and designs the belief criteria decision-making approach. A cost function considering a trade-off among belief state, path length and movement effort is modelled to select the next best location in path planning.

The semantic information is successfully modelled and propagated, which can represent the belief of finding object. The belief criteria decision-making (BCDM) approach is evaluated in both Gazebo simulation platform and physical experiments. Compared to greedy, uniform and random methods, the performance index of path length and execution time is superior by BCDM approach.

The prior knowledge of robot working environment, especially semantic information, can be used for path planning to achieve efficient task execution in path length and execution time. The modelling and updating of environment information can lead a promising research topic to realize a more intelligent decision-making method for object search task.

The aim of this study is to offer a contemporary approach for getting optical soliton and traveling wave solutions for the Date–Jimbo–Kashiwara–Miwa equation.

The approach is based on a recently constructed ansätze strategy. This method is an alternative to the Painleve test analysis, producing results similarly, but in a more practical, straightforward manner.

The approach proved the existence of both singular and optical soliton solutions. The method and its application show how much better and simpler this new strategy is than current ones. The most significant benefit is that it may be used to solve a wide range of partial differential equations that are encountered in practical applications.

The approach has been developed recently, and this is the first time that this method is applied successfully to extract soliton solutions to the Date–Jimbo–Kashiwara–Miwa equation.

This paper aims to further contribute to the growing stream of literature on the CEO's impact on corporate social responsibility (CSR). The authors shed light on the implications of attunement theory on which relatively less research has been done. Furthermore, this paper strives to reconcile contradictory findings of the effect of CEO tenure on CSR and use the immediate changes of CSR enacted by the new CEO upon firm value.

The empirical strategy of the paper is centered around CEO transition. Applying first difference model, the authors identify a tenure-varying pattern of CEO influence on CSR. Moreover, the authors base the analyses of CSR value relevance on the sudden change of CSR during CEO transition, and use a within-industry matching approach as the inferential strategy. Manual data collection is conducted extensively for robustness checks.

The authors find that CSR activities change drastically at the beginning of the new CEO's ascendancy. One exception to this general pattern of CSR policy change is when the new CEO is brought from outside the organization, a result supporting the attunement theory. The authors find that firm value increases (decreases) when the new CEO increases (decreases) the CSR investment above (below) the industry norm.

This paper is among the first ones in the extant literature that directly examines the analytical implications of attunement theory concerning the CEO's impact on the firm's CSR policies. Furthermore, the positive association between CSR and firm value corroborates the arguments of instrumental stakeholder theory.

With the rapid development of the sharing economy in manufacturing industries, manufacturers and the equipment suppliers frequently share capacity through the third-party platform. This paper aims to study influences of manufacturers sharing capacity on the supplier and to analyze whether the supplier shares capacity as well as its influences.

This paper deals with conditions that the supplier and manufacturers share capacity through the third-party platform, and the third-party platform competes with the supplier in equipment sales. Considering the heterogeneity of the manufacturer's earning of unit capacity usage and the production efficiency of manufacturer's usage strategies, this paper constructs capacity sharing game models. Then, model equilibrium results under different sharing scenarios are compared.

The results show that when the production or maintenance cost is high, manufacturers sharing capacity simultaneously benefits the supplier, the third-party platform and manufacturers with high earnings of unit capacity usage. When both the rental efficiency and the production cost are low, or both the rental efficiency and the production cost are high, the supplier simultaneously sells equipment and shares capacity. The supplier only sells equipment in other cases. When both the rental efficiency and the production cost are low, the supplier’s sharing capacity realizes the win-win-win situation for the supplier, the third-party platform and manufacturers with moderate earnings of unit capacity usage.

This paper innovatively examines supplier's selling and sharing decisions considering manufacturers sharing capacity. It extends the research on capacity sharing and is important to supplier's operational decisions.

This paper aims to explore the impact of flexible human resource management system (FHRMS) on employee innovation performance in Chinese context. The boundary conditions of employability and organizational identity are also discussed.

This study is based on 322 questionnaire survey from employees in China. The questionnaires were collected at two time points. This study used the method of multi-level linear model analysis for empirical test.

This study has three conclusions. First, FHRMS have a significant positive impact on employee innovation performance, with employability playing a mediating role. Second, organizational identity plays a moderating role between employability and employee innovation performance. Third, organizational identity moderates the mediating effect of a human source management systems on employee innovation performance through employability.

The results are helpful to open the “black box” of the influence of FHRMS on employees’ individual innovation performance. This study provides a reference for enterprises to establish flexible human source management system to improve employee innovation performance.