Chun Tian, Gengwei Zhai, Mengling Wu, Jiajun Zhou and Yaojie Li
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Liu-Qing Li, Yi-Tian Gao, Xin Yu, Gao-Fu Deng and Cui-Cui Ding
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Zhiping Zhu, Chen Tian, Xiyao Shi, Tao Li and Shangming Zhou
The purpose of this paper is to study the effect of nano polypyrrole-modified boron nitride on the performance of phosphate film.
Abstract
Purpose
The purpose of this paper is to study the effect of nano polypyrrole-modified boron nitride on the performance of phosphate film.
Design/methodology/approach
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.
Findings
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.
Originality/value
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.
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Roulin Chen and Ling Cao
Drawing on the “Resource- Capability – Competitive advantage” framework within Natural Resource-Based View, this study is purposed to address problems of manufacturing companies…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Practical implications
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.
Social implications
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.
Originality/value
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.
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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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
The simulation and experimental results are coincident with the theoretical analyses, which prove the effectiveness of the proposed method on harmonic suppression.
Practical implications
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.
Originality/value
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.
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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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Originality/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.
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Muhammad Bilal, Zhao Xicang, Wu Jiying, Jan Muhammad Sohu and Sadaf Akhta
In the era of digitalization, digital technology has transformed businesses and created enormous opportunities for organizations worldwide. Unsurprisingly, research on digital…
Abstract
Purpose
In the era of digitalization, digital technology has transformed businesses and created enormous opportunities for organizations worldwide. Unsurprisingly, research on digital transformation has garnered significant interest among academics in recent decades. However, this study aims to recognize the key and holistic antecedents influencing digital transformation in manufacturing firms. This study also investigates the indirect relationships of antecedents with firm performance.
Design/methodology/approach
The hypothesis was investigated using the partial least squares structural equation modeling (PLS-SEM) approach. The data was collected from 279 employees through a self-administered survey of manufacturing firms.
Findings
The results described a significant and positive impact of competitive pressure, leadership role, organization culture, organization mindfulness, government regulation, and IT readiness on digital transformation and firm performance. Furthermore, digital transformation partially mediates the relationship between antecedents and firm performance.
Originality/value
The study finds a holistic perspective of the critical antecedents of digital transformation using the mediation role of digital transformation and moderating effects of firm agility. Additionally, all antecedents have a significant association with Firm Performance.
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Hulya Turkcan, Salih Zeki Imamoglu and Huseyin Ince
The purpose of this paper is to investigate the relationships between augmented reality, process innovativeness and operational performance.
Abstract
Purpose
The purpose of this paper is to investigate the relationships between augmented reality, process innovativeness and operational performance.
Design/methodology/approach
This research is based on a quantitative approach using a questionnaire survey from a total of 117 firms in the automotive sector. The hypothesized relationships are tested using partial least square structural equation modeling (PLS-SEM).
Findings
This study demonstrates that augmented reality is positively associated with process innovativeness, and process innovativeness is positively related to operational performance. Furthermore, it is found that process innovativeness fully mediates the relationship between augmented reality and operational performance.
Originality/value
Although augmented reality attracts great attention from academics and practitioners, the current literature lacks an empirical investigation on how augmented reality creates value for the business. Addressing this crucial gap, this research is the first attempt to empirically reveal the role of augmented reality in facilitating process innovativeness and also unearthing how augmented reality improves operational performance. Therefore, this study offers novel insights into the role of augmented reality in business and provides theoretical and managerial contributions.
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Fusheng Xie, Ling Gao and Peiyu Xie
This paper examines the different features of China's economic development in different stages of economic globalization. The study finds that the investment- and export-based…
Abstract
Purpose
This paper examines the different features of China's economic development in different stages of economic globalization. The study finds that the investment- and export-based growth model drove China's high-speed economic growth between 2000 and 2007, which came into existence around 2000 when China plugged into the global production network.
Design/methodology/approach
This paper also finds that China slowed down to the New Normal because of the disruption to the socio-economic underpinnings of this growth model. As China adapts to and steers the New Normal, supply-side structural reforms can channel excess capacity to the construction of underground pipe networks in rural areas of central China and fix capital while advance rural revitalization.
Findings
At the same time, enterprises must strive to build a key component development platform for key component innovation and the standard-setting power in global manufacturing.
Originality/value
The establishment of a domestic production network integrating the integrated innovation-driven core enterprises and modular producers at different levels can satisfy the dynamic demand structure of China in which standardized demands and personalized demands coexist.
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Xiuyun Yang and Qi Han
The purpose of this study is to investigate whether the corporate environmental, social and governance (ESG) performance of enterprise is influenced by the enterprise digital…
Abstract
Purpose
The purpose of this study is to investigate whether the corporate environmental, social and governance (ESG) performance of enterprise is influenced by the enterprise digital transformation. In addition, this study explains how enterprise digital transformation affects ESG performance.
Design/methodology/approach
The sample covers 4,646 nonfinancial companies listed on China’s A-share market from 2009 to 2021. The study adopts the fixed-effects multiple linear regression to perform the data analysis.
Findings
The study finds that enterprise digital transformation has a significant inverted U-shaped impact on ESG performance. Moderate digital transformation can improve enterprise ESG performance, whereas excessive digital transformation will bring new organizational conflicts and increase enterprise costs, which is detrimental to ESG performance. This inverted U-shaped effect is more pronounced in industrial cities, manufacturing industries and enterprises with less financing constraints and executives with financial backgrounds. Enterprise digital transformation mainly affects ESG performance by affecting the level of internal information communication and disclosure, the level of internal control and the principal-agent cost.
Practical implications
The government should take multiple measures to encourage enterprises to choose appropriate digital transformation based on their own production behaviors and development strategies, encourage them to innovate and upgrade their organizational management and development models in conjunction with digital transformation and guide them to use digital technology to improve ESG performance.
Social implications
This study shows that irrational digital transformation cannot effectively improve the ESG performance of enterprises and promote the sustainable development of the country. Enterprises should carry out reasonable digital transformation according to their own development needs and finally improve the green and sustainable development ability of enterprises and promote the sustainable development of society.
Originality/value
This study examines the relationship between enterprise digital transformation and ESG performance. Different from the linear relationship between the two in previous major studies, this study proves the inverse U-shaped relationship between enterprise digital transformation and ESG performance through mathematical theoretical model derivation and empirical test. This study also explores in detail how corporate digital transformation affects ESG performance, as well as discusses heterogeneity at the city, industry and firm levels. It is proposed that enterprises should take into account their own characteristics and carry out reasonable digital transformation according to their development needs.