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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.

This paper aims to study the Gramian solutions and solitonic interactions of a (2 + 1)-dimensional Broer–Kaup–Kupershmidt (BKK) system, which models the nonlinear and dispersive long gravity waves traveling along two horizontal directions in the shallow water of uniform depth.

Pfaffian technique is used to construct the Gramian solutions of the (2 + 1)-dimensional BKK system. Asymptotic analysis is applied on the two-soliton solutions to study the interaction properties.

N-soliton solutions in the Gramian with a real function ζ(y) of the (2 + 1)-dimensional BKK system are constructed and proved, where N is a positive integer and y is the scaled space variable. Conditions of elastic and inelastic interactions between the two solitons are revealed asymptotically. For the three and four solitons, elastic, inelastic interactions and soliton resonances are discussed graphically. Effect of the wave numbers, initial phases and ζ(y) on the solitonic interactions is also studied.

Shallow water waves are studied for the applications in environmental engineering and hydraulic engineering. This paper studies the shallow water waves through the Gramian solutions of a (2 + 1)-dimensional BKK system and provides some phenomena that have not been studied.

The purpose of this paper is to study the effect of nano polypyrrole-modified boron nitride on the performance of phosphate film.

By adding polypyrrole-modified boron nitride to the phosphate solution, a phosphate film is formed on the metal surface, improving its corrosion resistance. The effect of different concentrations of polypyrrole-modified boron nitride on the corrosion resistance of Q235 carbon steel surface was studied. The corrosion resistance of the phosphate film was evaluated using the copper sulfate drop test. The electrochemical corrosion performance of the phosphate film was assessed using the weak polarization curve method and electrochemical impedance spectroscopy. The surface of the samples was characterized using scanning electron microscopy and X-ray diffraction analysis.

The results show that samples containing polypyrrole-modified boron nitride have a denser and more uniform phosphate film. When the concentration of polypyrrole-modified boron nitride is 0.6 g/L, the drop time of copper sulfate on the formed phosphate film can reach 219 s, which is a 189% increase compared to the performance of the sample without the additive. The current density is 1.06 × 10⁻⁶ A/cm² lower than that of the pure phosphate film, indicating the best corrosion resistance. Polypyrrole-modified boron nitride effectively promotes the formation of the phosphate film.

This study used the modification of phosphate solution using nanoparticles to investigate the influence of different nanoparticle concentrations on the phosphate film. The corrosion resistance of the phosphate film was enhanced, providing a method and theoretical guidance for the improvement of phosphate solution formulation.

Drawing on the “Resource- Capability – Competitive advantage” framework within Natural Resource-Based View, this study is purposed to address problems of manufacturing companies “turning into the green” issues, providing references for manufacturing companies to achieve green competitive advantage via internal motivation and identity perspectives.

This study collected survey data from 112 Chinese manufacturing listed enterprises from the Shanghai Stock Exchange, and obtained 418 questionnaires. Following an empirical design, hierarchical regression analysis and Bootstrapping analysis were applied to examine these hypotheses.

Results show that green innovation behaviors positively mediate the positive relationship between organizational environmental identity and green competitive advantage. Furthermore, slack resource not only positively moderates the interaction effect between organizational environmental identity and green product innovation behaviors, but also moderates the mediation role of green product innovation behavior in the main effect.

The study is limited to the data samples and dynamic evolution between variables. More longitudinal designs and diverse enterprise fields will be considered in future.

The findings provide guidance for manufacturing enterprises to gain green competitive advantage in green manufacturing era from identity value origins. Moreover, the results provide practical suggestions for manufacturing enterprises to enhance green innovation behaviors and integrate useful but slack resources.

The findings provide implications for manufacturing industry to increase both the awareness of organizational environmental identity and green innovation behaviors, all of which helps promote the corporate environmental responsibility.

The study breaks the limitation of the existing literature which focuses on the influence of external push factors (e.g. environmental regulation), and bring new visions in constructing green competitive advantage in green manufacturing era, not only extending the identity theory and upper echelon theory, but also enriching the current studies on green management. Also, these findings provide deeper and new insights into risks and uncertain features of green manufacturing era, analyzing how polluted manufacturing enterprises obtain green competitive advantages through the mediating role of green innovation behaviors and the moderating role of slack resource.

As arc suppression coils (ASCs), magnetically controlled reactors (MCRs) are usually operated in the single-phase mode. Due to the lack of a third order harmonic compensation circuit, the current harmonics are high. The purpose of this paper is to propose a novel structure of MCR and a genetic algorithm (GA) to determine the parameters which will result in minimum total harmonics.

This paper proposes the structure and the working principle of the multi-valve controlled saturable reactor (MCSR). There are several sorts of magnetic valves in the iron cores of the MCSR. The saturation degree of each magnetic valve is different when the same direct component of the magnetic flux is generated in the iron core, therefore current harmonics of different phases emerging, i.e. the total harmonics can be reduced. The magnetization characteristics and the mathematical model of the current harmonics of the MCSR are presented by introducing three parameters. The optimal values of the parameters that result in the smallest total harmonic distortion in the output current are calculated by a GA.

The simulation and experimental results are coincident with the theoretical analyses, which prove the effectiveness of the proposed method on harmonic suppression.

The method proposed in this paper can successfully reduce the current harmonics of the conventional MCR, including but not limited to the ASC. A prototype MCSR (540 kVA/10 kV) has been designed and constructed.

In this paper, a MCSR is proposed. The mathematical model of the MCSR for harmonic analysis is developed. The optimal parameters that result in the smallest THD in the output current are calculated. The mathematical model can be also used for the harmonic analysis of conventional MCRs.

Customer resource allocation efficiency (RAE) refers to the ability of customers to use, allocate and manage their available resource inputs to produce valuable outputs. This study draws on organizational entrainment theory (OET) to examine how the implementation of supplier digitalization affects customer RAE through supply chain entrainment.

Based on supplier and customer data disclosed by Chinese A-share listed firms from 2009 to 2022, this study uses fixed effects panel data models to empirically examine the impact of supplier digitalization on customer RAE and the mechanistic role of supply chain entrainment.

The results show that supplier digitalization significantly increases customer RAE. It improves RAE by influencing the three dimensions of supply chain entrainment (the bullwhip effect, inventory management coordination and risk management coordination).

This study provides important insights into how managers can adapt the external digital environments and maintain synchronous operations with their supply partners. Our findings demonstrate how managers can fully leverage the advantages of digitalization of their suppliers to improve their own RAE through supply chain entrainment strategies.

This study introduces the concept of supply chain entrainment to reveal how firms optimize their own resource allocation strategies and achieve efficient operations. Our research enriches the understanding of supply chain governance in the digital age and contributes to the literature on supply chain digitalization.

The study aims to contribute to the debate on how to identify and manage an organization’s sustainability-related resources and processes by understanding the impact of business activities on the environment and evaluating actions to ameliorate their impacts. Within this debate, and specifically taking into consideration the opportunity to support circular economy actions and initiatives, the study focuses on integrated reporting (IR) practices. In detail, this study advocates the joint use of IR principles with the dynamic resource-based view (DRBV) of the firm, adopting their representation of resources and impact of the business activities to identify environmental friendly “hot spots” in organizations. The framework is illustrated through two exploratory case studies.

The survival of companies today hinges on their adaptability and flexibility, with digital transformation (DT) and organizational slack (OS) playing crucial roles. Despite their recognized importance, these factors are often studied separately. This study aims to explore how OS facilitates DT and evaluate their synergies and trade-offs to improve performance.

Using data from the European Manufacturing Survey, structural equation modeling (PLS-SEM) and fuzzy set qualitative comparative analysis (fsQCA), we investigate causal relationships and possible combinations between different dimensions of OS and DT that contribute to business performance.

We confirmed the positive effect of OS and DT on business performance, highlighting the importance of organizational over technological factors. While not definitively establishing OS as a precursor to DT, our findings underscore the need for human and operational slack to improve performance, especially in less technology-intensive contexts.

Our findings evidence that decision-makers should integrate OS with DT initiatives to improve the firm’s competitiveness. However, it is worth noting that while OS seems essential in low-tech shopfloors, its importance is lower in high-tech environments. Furthermore, within the possible combinations, managers should promote operational slack and digitalization, as it seems fundamental to improve business performance.

This article contributes to the management field in three ways. First, it clarifies controversies by providing evidence of the positive roles of DT and OS as drivers of competitiveness for manufacturing firms. Second, we verify that OS is not directly linked to DT, challenging existing assumptions. Third, it investigates the combinations of OS and DT that drive business performance improvement, emphasizing their synergies and trade-offs.

This study aims to examine the impact of digital transformation on firms’ value and explore the mediating impact of ESG performance and moderating impact of information interaction.

Data was collected from companies listed on the Shanghai and Shenzhen stock exchange between 2012 and 2020 with 21,488 observational samples, featuring a selection of 3,348 companies. Panel data regression techniques were used to test the mediating role of ESG performance and the moderating role of information interaction.

The study found that digital transformation can improve firms’ ESG performance, which in turn positively affects their value. The firms that engage in more interaction with outsiders benefit more from digital transformation and have a higher value.

This study provides new theoretical insight into improving firms’ value through digital transformation and ESG performance. It is the first to discuss and study the moderating role of information interaction in the relationship between digital transformation and firms’ value.