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This paper aims to demonstrate the effect of varying chromium content on the wear behavior of white cast iron, to study the interaction relationship between cementite and pearlite in white cast iron, while estimating their contribution rate in abrasive wear.

To study interaction of cementite-pearlite of white cast irons with different chromium content in three-body abrasive wear, three kinds of chromium white cast iron, bulk single-phase cementite, pure pearlite samples and the white cast iron (WCI), were prepared using the melting and casting technique. The so-called pure pearlite samples have the same chemical composition, microstructure and properties as the pearlite matrix in white cast iron.

Results indicated that the interaction has a negative value. Its absolute value decreased with increasing chromium addition. Meanwhile, a high load resulted in an increased interaction value. The contribution rate of cementite to interaction, which was higher than that of pearlite, increased with increasing chromium addition. This indicated cementite was a main phase. Besides, the reductive size of abrasive has a significant effect on the contribution rate at the high load. These prominent cementite occurred fracture, when small size abrasive indented the matrix. These result in the absence of a protective effect of cementite during wear process. Eventually, the contribution rate of cementite decreased significantly.

This paper demonstrates the effect of varying chromium content on wear behavior of white cast iron, to study the interaction relationship between cementite and pearlite in white cast iron while estimating their contribution rate in abrasive wear.

Although a laser profile sensor (LPS) can be used to measure dimensions, the “shadow region” generally degrades the accuracy and precision of width measurements. The accuracy and precision of such measurements should be improved.

In this paper, the authors propose herein a technique that combines high dynamic range (HDR) imaging with logistic fitting. First, a HDR image is composed of several images acquired with different exposure times, which augments the grayscale of the object profile and significantly reduces overexposure. Next, the profile is fit to a logistic function, which provides accurate and precise edge coordinates. Finally, given the edge coordinates, the object width is calculated.

To verify the stability of this logistic algorithm, the authors simulate different noise conditions and different degrees of incomplete edge data. In addition, the progressiveness of the algorithm is demonstrated by comparing the results with those of other algorithms and with the height measurement. Furthermore, the suitability of the system is verified experimentally.

Because of the limitation of the condition of laboratory, in the experimental section, this paper cannot represent perfectly the industrial situation. It makes this section limited in demonstration.

In this paper, the results show that the measurement accuracy and precision of the width is improved and exceeds that of the height measurement. The proposed HDR imaging method with logistic fitting may be applied to LPS width measurements, which should significantly aid the development of LPSs.

This paper aims to study the influence of aerodynamics force of trains passing each other on the dynamic response of vehicle bridge coupling system based on numerical simulation and multi-body dynamics and put forward the speed threshold for safe running of train under different crosswind speeds.

The computational fluid dynamics method is adopted to simulate the aerodynamic force in the whole process of train passing each other by using dynamic grid technology. The dynamic model of vehicle-bridge coupling system is established considering the effects of aerodynamic force of train passing each other under crosswind, the dynamic response of train intersection on the bridge under crosswind is computed and the running safety of the train is evaluated.

The aerodynamic force of trains' intersection has little effects on the derailment factor, lateral wheel-rail force and vertical acceleration of train, but it increases the offload factor of train and significantly increases the lateral acceleration of train. The crosswind has a significant effect on increasing the derailment factor, lateral wheel-rail force and offload factor of train. The offload factor of train is the key factor to control the threshold of train speed. The impact of the aerodynamic force of trains' intersection on running safety cannot be ignored. When the extreme values of crosswind wind speed are 15 m·s⁻¹, 20 m·s⁻¹ and 25 m·s⁻¹, respectively, the corresponding speed thresholds for safe running of train are 350 km·h⁻¹, 275 km·h⁻¹ and 200 km·h⁻¹, respectively.

The research can provide a more precise numerical method to study the running safety of high-speed trains under the aerodynamic effect of trains passing each other on bridge in crosswind.

The determinants that contribute to reducing stock price crash risk have garnered attention from scholars and practitioners. However, our understanding of the relationship between board diversity and stock crash risk, as well as the contextual factors that influence this relationship, remains limited. To address this gap, this study aims to investigate how different attributes of board diversity affect stock price crash risk, particularly under conditions of higher performance hazard and ownership concentration.

Using a two-stage least squares fixed-effects estimator, the authors analyze a panel data set of 1,792 firm-year observations across 282 firms listed on the KOSPI200 from 2010 to 2019.

Relation-oriented diversity reduces future stock price crash risk, particularly when firms experience performance shortfalls and have concentrated ownership structures, but task-oriented diversity has no significant effects. The results imply that only relation-oriented diversity strengthens governance mechanisms by curtailing managerial bad news withholding behaviors, and the role of relation-oriented diversity in reducing stock crash risk becomes more crucial when firms have higher performance hazard and concentrated ownership.

This study makes crucial contributions as follows: the authors contribute to the stock crash risk literature by shifting the focus from how to when board diversity matters in assessing stock crash risk; the authors extend the board diversity research and enhance scholarly understanding of the effects of board diversity on corporate governance by highlighting that not all aspects of board diversity improve firm governance mechanisms; and the authors widen the lens from a single attribute to multiple attributes of diversity to reveal the effects of diversity on boards in assessing future crash risk.

The purpose of this study is to unpack the antecedents and consequences of clickbait prevalence in online media at two different levels, namely, (1) Headline-level: what characteristics of clickbait headlines attract user clicks and (2) Publisher-level: what happens to publishers who create clickbait on a prolonged basis.

To test the proposed conjectures, the authors collected longitudinal data in collaboration with a leading company that operates more than 500 WeChat official accounts in China. This study proposed a text mining framework to extract and quantify clickbait rhetorical features (i.e. hyperbole, insinuation, puzzle, and visual rhetoric). Econometric analysis was employed for empirical validation.

The findings revealed that (1) hyperbole, insinuation, and visual rhetoric entice users to click the baited headlines, (2) there is an inverted U-shaped relationship between the number of clickbait headlines posted by a publisher and its visit traffic, and (3) this non-linear relationship is moderated by the publisher's age.

This research contributes to current literature on clickbait detection and clickbait consequences. Future studies can design more sophisticated methods for extracting rhetorical characteristics and implement in different languages.

The findings could aid online media publishers to design attractive headlines and develop clickbait strategies to avoid user churn, and help managers enact appropriate regulations and policies to control clickbait prevalence.

The authors propose a novel text mining framework to quantify rhetoric embedded in clickbait. This study empirically investigates antecedents and consequences of clickbait prevalence through an exploratory study of WeChat in China.

Male celebrities are increasingly being chosen to endorse female cosmetic brands by marketing managers, yet this practice has not received sufficient scholarly attention. This study aims to explore the dynamics of male celebrities endorsing cosmetic brands.

The study employs the netnography approach to collect data from an online community.

The study contributes to the marketing literature by providing a conceptual framework of male celebrities endorsing cosmetic brands, highlighting the key attributes that contribute to the effectiveness of these endorsements, the evolution of relationships between fans, celebrities and brands, the features of this dynamic relationship and the influence of male celebrity endorsements on fans’ purchase decisions.

This research sheds light on an emerging trend in the marketing industry and provides valuable managerial insights for marketers seeking to effectively use male celebrity endorsements to promote female cosmetic brands.

With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.

This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.

China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.

This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.

The practice of renovation and construction of university libraries is flourishing, but how to attract readers to use the library is an issue that urgently needs to be explored. Spatial cognition is a subjective judgment of a person's tendency to take action in the future and implies behavioral intention. Based on the sensory–image–cognition relationship, a theoretical model of university library readers' spatial cognition is conducted, and the influencing factors and mechanisms of spatial cognition are explored based on empirical data to provide theoretical references for spatial practices in university libraries.

A visual and art-based mental map approach is introduced based on a questionnaire survey. The questionnaire is mainly used for the specific evaluation of spatial use and the breakdown of the detailed elements, while the mental map method is mainly used for the evaluation of readers' spatial cognition. Relevant empirical data are collected from the library of the Zhejiang University of Technology.

The results indicate that readers' spatial sensory experience and mental imagery have positive effects on readers' behavior via the mediator spatial cognition, readers' spatial sensory experience and mental imagery have a positive effect on readers' spatial cognition and spatial cognition has a significant effect on readers' behavior.

The main contribution of this study is to construct a theoretical model of readers' spatial cognition and to explore the factors that have an impact on spatial cognition and the influence of cognition on behavior. This provides a more rational and in-depth thinking paradigm for the study of university library space and provides theoretical references for library practice.

A little-known “lottery fever” has spread to many parts of rural China over the past 10 years. This is driven by participation in underground lotteries with local bookies. It is called liuhecai, which is the name of the Hong Kong lottery, and is based on guessing the bonus number of the Hong Kong Mark Six lottery. Such lotteries are illegal, but are an open secret. This chapter seeks to understand the meaning of this apparently irrational lottery fever: why people participate in it, why they believe the conspiracy theory that it is rigged (and yet still participate), and why similar lotteries have emerged in both capitalist Taiwan and post-socialist China at this particular time.