Yangong Wu, Zheng Qiao, Jiadai Xue, Yutao Liu and Bo Wang
The purpose of this paper is to present a novel numerical approach to analyze the static performance of aerostatic thrust bearings by adopting a general finite element method…
Abstract
Purpose
The purpose of this paper is to present a novel numerical approach to analyze the static performance of aerostatic thrust bearings by adopting a general finite element method calculation program.
Design/methodology/approach
The characteristics of a gas film are described by the Reynolds equation and the pressure distribution is solved using the finite element method. A root iterative method is proposed to meet the requirement of the mass-conservation law because multiple pocketed orifice-type restrictors are treated as a series of special boundary conditions.
Findings
The static performance of a rotary table using aerostatic thrust bearings, including load carrying capacity and stiffness, can be predicted by the method; moreover, it can be further confirmed through experiments on the designed rotary table.
Originality/value
The method combining the finite element and root iterative methods is highly accurate and has a low time-cost for analyzing aerostatic thrust bearings with multiple pocketed orifice-type restrictors.
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Daozhong Wang, Xiaoxia Yan, Junxin Li and Yutao Liu
The wheel wear of high-speed trains is the main concern in the operation process of the high-speed trains. Wheel reprofile usually adopts the thin flange wheel profiles for the…
Abstract
Purpose
The wheel wear of high-speed trains is the main concern in the operation process of the high-speed trains. Wheel reprofile usually adopts the thin flange wheel profiles for the economic wheel reprofile strategy; however, the wheel wear evolution law of the thin flange wheel profile is not clear. The purpose of this paper mainly researches the wheel wear evolution law of thin flange wheel profile and the influence factors of thin flange wheel.
Design/methodology/approach
To solve this problem, this paper analyzed the wheel-rail contact relationship and established a vehicle dynamic model of high-speed train. The Jendel wheel wear model was used to analyze the evolution of thin flange wheel wear and rail deviation affecting wheel wear under thin flange wheel profiles.
Findings
Due to the consistency of the tread area, the distribution of wheel-rail contact points for thin flange wheels in the tread area is close. As the wheel flange increases, wheel wear also increases. Thin flange wheel profiles reduce wheel wear to a certain extent. The maximum wheel wear depths with rail deviations of −0.4 mm, 0 mm and 0.4 mm are 0.9844 mm, 1.077 mm and 1.142 mm, respectively. The negative rail deviation suppresses wheel wear, but the positive rail deviation increases wheel wear.
Originality/value
The evolution of wheel wear for thin flange wheels after reprofiling is not clear. This paper analyzed the wear characteristics of thin flange wheel wear and rail deviation affecting wheel wear under thin flange wheels.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2024-0401/
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Qibiao Yang, Yunhan You, Bojin Cheng, Lie Chen, Jian Cheng, Deyuan Lou, Yutao Wang and Dun Liu
The purpose of this study is to process the wettability surface of the ZrO2 ceramics to improve their surface friction performance.
Abstract
Purpose
The purpose of this study is to process the wettability surface of the ZrO2 ceramics to improve their surface friction performance.
Design/methodology/approach
Microtexture was processed on the surface of ZrO2 ceramics using a femtosecond laser. The three-dimensional texture morphology, surface contact angle, friction curve and wear morphology were measured by the laser confocal microscope, the contact angle meter, the reciprocating friction and wear tester and the scanning electron microscope, respectively. Based on Wenzel and partial impalement models, a geometric model of micro pits is established to study the influence mechanism of micro pit depth, diameter and distribution density on wettability and to analyze the relationship between surface wettability and tribological properties.
Findings
The results show that changing the geometric characteristics of the texture will lead to a change in the solid-liquid contact mode, and then lead to a change of in the surface contact angle. Wettability is an essential factor that affects the reduction of surface friction. The construction of a reasonable texture can enhance the surface hydrophilicity, which is conducive to the formation of a lubricating film on the ceramic surface, thereby reducing abrasive and adhesive wear, and improving the wear resistance of the ZrO2 ceramic surface.
Originality/value
The results provide a theoretical reference for femtosecond laser surface texture wettability regulation and tribological performance improvement.
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Zhiqi Liu, Tanghong Liu, Hongrui Gao, Houyu Gu, Yutao Xia and Bin Xu
Constructing porous wind barriers is one of the most effective approaches to increase the running safety of trains on viaducts in crosswinds. This paper aims to further improve…
Abstract
Purpose
Constructing porous wind barriers is one of the most effective approaches to increase the running safety of trains on viaducts in crosswinds. This paper aims to further improve the wind-sheltering performance of the porous wind barriers.
Design/methodology/approach
Improved delayed detached eddy simulations based on the k-ω turbulence model were carried out, and the results were validated with wind tunnel tests. The effects of the hole diameter on the flow characteristics and wind-sheltering performance were studied by comparing the wind barriers with the porosity of 21.6% and the hole diameters of 60 mm–360 mm. The flow characteristics above the windward and leeward tracks were analyzed, and the wind-sheltering performance of the wind barriers was assessed using the wind speed reduction coefficients.
Findings
The hole diameters affected the jet behind the wind barriers and the recirculation region above the tracks. Below the top of the wind barriers, the time-averaged velocity first decreased and then increased with the increase in the hole diameter. The wind barrier with the hole diameter of 120 mm had the best wind-sheltering performance for the windward track, but such barrier might lead to overprotection on the leeward track. The wind-sheltering performance of the wind barriers with the hole diameters of 240 mm and 360 mm was significantly degraded, especially above the windward track.
Originality/value
The effects of the hole diameters on the wake and wind-sheltering performance of the wind barriers were studied, by which the theoretical basis is provided for a better design of the porous wind barrier.
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Xiaoming Sun, Fayou Lei, Yalan Wang and Ruobing Ren
The purpose of this paper is to study the influence mechanism of different levels of social capital (Structure holes–local network attributes and indirect ties–global network…
Abstract
Purpose
The purpose of this paper is to study the influence mechanism of different levels of social capital (Structure holes–local network attributes and indirect ties–global network attributes) and organizational culture on the creativity of key inventors, and the role of organizational culture between social capital and creativity.
Design/methodology/approach
The paper tested the hypotheses with a sample of patent data accumulated from 46 firms in Chinese electronic information and automobile sectors. Negative binomial regression was used to explore the factors influencing the creativity of key inventors.
Findings
The paper discovers that structural holes are valuable social capital for the creativity of key inventors and very important in firms with a collective and conservative culture. Moreover, it also locates that key inventor are more creative in firms with an individualistic and competitive culture than those in firms with a collective and conservative culture.
Originality/value
This study emphasizes the influence of social capital on creativity and contributes to R&D management. It highlights structural holes are certainly important to key inventors in a collective and conservative culture, thus contradicting preceding studies that locate structural holes useful solely in an individualistic culture. This finding broadens our knowledge of the benefits of this network structure. Also, this debate challenges several basic views on structural holes currently.
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Lijun (Gillian) Lei, Yutao Li and Yan Luo
The emergence of social media as a corporate disclosure channel has caused significant changes in the production and dissemination of corporate information. This review identifies…
Abstract
The emergence of social media as a corporate disclosure channel has caused significant changes in the production and dissemination of corporate information. This review identifies important themes in recent research on the impact of social media on the corporate information environment and provides suggestions for further explorations of this new but fast-growing area of research. Specifically, we first review the evolution of Internet-based corporate disclosure and related regulations, and then focus on three recent streams of research: 1) companies’ use of social media; 2) information produced by non-corporate users and its impact on capital markets; and 3) the credibility of corporate information on social media platforms.
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Chengcheng Liao, Peiyuan Du, Yutao Yang and Ziyao Huang
Although phone calls are widely used by debt collection services to persuade delinquent customers to repay, few financial services studies have analyzed the unstructured voice and…
Abstract
Purpose
Although phone calls are widely used by debt collection services to persuade delinquent customers to repay, few financial services studies have analyzed the unstructured voice and text data to investigate how debt collection call strategies drive customers to repay. Moreover, extant research opens the “black box” mainly through psychological theories without hard behavioral data of customers. The purpose of our study is to address this research gap.
Design/methodology/approach
The authors randomly sampled 3,204 debt collection calls from a large consumer finance company in East Asia. To rule out alternative explanations for the findings, such as consumers' previous experience of being persuaded by debt collectors or repeated calls, the authors selected calls made to delinquent customers who had not been delinquent before and were being called by the company for the first time. The authors transformed the unstructured voice and textual data into structured data through automatic speech recognition (ASR), voice mining, natural language processing (NLP) and machine learning analyses.
Findings
The findings revealed that (1) both moral appeal (carrot) and social warning (stick) strategies decrease repayment time because they arouse mainly happy emotion and fear emotion, respectively; (2) the legal warning (stick) strategy backfires because of decreasing the happy emotion and triggering the anger emotion, which impedes customers' compliance; and (3) in contrast to traditional wisdom, the combination of carrot and stick fails to decrease the repayment time.
Originality/value
The findings provide a valuable and systematic understanding of the effect of carrot strategies, stick strategies and the combinations of them on repayment time. This study is among the first to empirically analyze the effectiveness of carrot strategies, stick strategies and their joint strategies on repayment time through unstructured vocal and textual data analysis. What's more, the previous studies open the “black box” through psychological mechanism. The authors firstly elucidate a behavioral mechanism for why consumers behave differently under varying debt collection strategies by utilizing ASR, NLP and vocal emotion analyses.
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Chengyee Janie Chang, Yutao Li and Yan Luo
The purpose of this study is to examine how auditors would react when there are exogenous negative shocks to their client portfolios.
Abstract
Purpose
The purpose of this study is to examine how auditors would react when there are exogenous negative shocks to their client portfolios.
Design/methodology/approach
Using a sample of 31,256 firm-year observations (2001–2016), the authors investigate whether industry shocks to a subset of an auditor’s clients distract the auditor and affect the professional skepticism applied in the audits of other clients.
Findings
The authors find that clients of distracted auditors are more likely to meet or beat analyst consensus forecasts, suggesting that auditors’ professional skepticism is compromised by distractive events. The cross-sectional analyses reveal that the negative impact of the distractive events on audit quality is more pronounced when the distracted auditors audit less important clients, face lower third-party legal liabilities and experience higher growth. Using an alternative measure of audit quality, the additional analysis shows that clients of distracted auditors exhibit a higher probability of restating their earnings in subsequent years. Overall, the empirical evidence suggests that when distracted, auditors render lower quality audit.
Originality/value
The study complements recent work by Cassell et al. (2019), which shows that the 2008–2009 financial crisis affected the quality of the audits of nonbank clients of bank-specialized auditors. While Cassell et al. (2019) focus on one shock (financial crisis) to one industry (i.e. the financial services industry), the study examines more frequent shocks over a wide range of industries to identify the potential effects of distractive events, improving the generalizability of the findings to all industries and all auditors (specialist and nonspecialist) in nonrecession periods.
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Jiawang Zeng, Ming-Zhi Yang, Lei Zhang, Tongtong Lin, Sha Zhong and Yu Tao
The aerodynamic load caused by high-speed train operation may lead to severe vibration of the pedestrian bridge, thus causing great safety hazards. Therefore, this study aims to…
Abstract
Purpose
The aerodynamic load caused by high-speed train operation may lead to severe vibration of the pedestrian bridge, thus causing great safety hazards. Therefore, this study aims to investigate the aerodynamic loading characteristics of a pedestrian bridge when a high-speed train passes over the bridge, as well as to evaluate the vibration response of the aerodynamic loads on the bridge structure.
Design/methodology/approach
High-speed trains are operated at three different speeds. The aerodynamic pressure load characteristics of high-speed trains crossing a pedestrian bridge are investigated by combining a nonconstant numerical simulation method with a dynamic modeling test method, and the vibration response of the bridge is analyzed.
Findings
The results show that when a high-speed train passes through the pedestrian bridge, the pedestrian bridge interferes with the attenuation of the pressure around the train, so that the pressure spreads along the bridge bottom, and the maximum positive and negative pressure peaks appear in the center area of the bridge bottom, while the pressure fluctuations in the bridge entrance and exit areas are smaller and change more slowly, and the pressure attenuation of the bridge bottom perpendicular to the direction of the train’s operation is faster. In addition, the pressure fluctuation generated by the high-speed train will lead to a larger vertical response of the bridge structure in the mid-span position, and the main vibration frequency of the bridge structure ranges from 8 to 10 Hz, and the maximum value of the vertical deformation amplitude is located in the mid-span region of the bridge.
Originality/value
This paper analyzes the flow field distribution around the train and at the bottom of the bridge for the evolution of the flow field when the train passes through the bridge at high speed, and conducts a finite element dynamic analysis of the bridge structure to calculate the vibration response of the bridge when the train passes through at high speed, and to evaluate the comfort of the passengers passing through the high-speed railroad bridge.
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Keywords
Ye Chen, Lei Shen, Xi Zhang and Yutao Chen
The purpose of this paper is twofold: first, to present a bibliometric analysis and systematic literature review of industry convergence and value innovation to understand the…
Abstract
Purpose
The purpose of this paper is twofold: first, to present a bibliometric analysis and systematic literature review of industry convergence and value innovation to understand the current research status; second, to provide a coherent theoretical research framework for future research.
Design/methodology/approach
This study adopts a two-step analysis approach by combining bibliometric analysis and systematic literature review to explore the research topic of industry convergence and value innovation. Besides, two bibliometric tools, HistCite and VOSviewer, were applied to this study.
Findings
This study found that Stefanie Bröring and Fredrik Hacklin are the top two most influential authors among all authors in the sample publications. Technological Forecasting and Social Change is one of the top-ranking journal that often publishes this topic of articles. Germany and the University of Munster are the most influential country and institutions, respectively. Besides, five core research themes were identified based on keywords co-occurrence map, theoretical lenses, factors promoting industry convergence, indicators of industry convergence, the impact of industry convergence and emerging research directions. Based on the above analysis, this paper constructed a theoretical research framework of industry convergence and value innovation.
Research limitations/implications
This paper only draw data from one database – Web of Science – which cannot provide broad coverage of the research topic. Besides, the bibliometric method of this paper is based on high local citation score and high-frequency words, articles in the skirting subjects’ area may not be analyzed.
Practical implications
With the rapid development of technology, such as nanotechnology, radio - frequency identification (RFID), etc., the iterative upgrading of products also comes. As a result, the boundary between industries is gradually blurred, and the phenomenon of industry convergence appears. Therefore, managerial decision-makers are facing challenges of how to respond to the convergence phenomena. From the firm level, firms are facing the problem of value innovation of the existing product, new product development and core competence improvement. Industries are facing the problem of transformation and upgrading. This paper provides certain theoretical insights for both firms and industries to guide the practice accordingly.
Originality/value
This paper is the first to use a bibliometric method to examine the topic of industry convergence and value innovation. In addition, this paper presents an in-depth analysis of this topic and provides a comprehensive theoretical research framework for future study.