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This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

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 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 work is to optimize the monitoring of vibrations on dynamometric test rigs for railway brakes. This is a quite demanding application considering the continuous increase of performances of high-speed trains that involve higher testing specifications for brake pads and disks.

In this work, authors propose a mixed approach in which relatively simple finite element models are used to support the optimization of a diagnostic system that is used to monitor vibration levels and rotor-dynamical behavior of the machine. The model is calibrated with experimental data recorded on the same rig that must be identified and monitored. The whole process is optimized to not interfere with normal operations of the rig, using common inertial sensor and tools and are available as standard instrumentation for this kind of applications. So at the end all the calibration activities can be performed normally without interrupting the activities of the rig introducing additional costs due to system unavailability.

Proposed approach was able to identify in a very simple and fast way the vibrational behavior of the investigated rig, also giving precious information concerning the anisotropic behavior of supports and their damping. All these data are quite difficult to be found in technical literature because they are quite sensitive to assembly tolerances and to many other factors. Dynamometric test rigs are an important application widely diffused for both road and rail vehicles. Also proposed procedure can be easily extended and generalized to a wide value of machine with horizontal rotors.

Most of the studies in literature are referred to electrical motors or turbomachines operating with relatively slow transients and constant inertial properties. For investigated machines both these conditions are not verified, making the proposed application quite unusual and original with respect to current application. At the same time, there is a wide variety of special machines that are usually marginally covered by standard testing methodologies to which the proposed approach can be successfully extended.

The substantial expansion of technology and the efficacy of digital platforms in reaching young audiences have led to enhanced targeting and customization of promotional communications. Notwithstanding the expansion and efficacy of contemporary advertising platforms, scholarly attention has not kept pace with this domain of inquiry. This study aims to assess the antecedents of Google Shopping Ads (GSA) on intention to purchase behavior among the Generation Y and Z cohorts.

The current study used a quantitative approach and snowball sampling technique to gather primary data via a questionnaire and Google Forms, which resulted in the collection of 5,808 questionnaires among the cohort members. A principal component analysis and multigroup confirmatory multigroup structural equation modeling (between Generation Y and Z) were used to assess the research data and model.

The results show positive trust and perceived value associations with intention to purchase, particularly among Generation Y and Z consumers. The findings also show negative irritation, product risk and time risk associations with intention to purchase, especially among the Generation Y cohort, which indicates that young consumers generally do not observe perceived risk due to the usage of GSA.

GSA will continue to grow and become an increasingly important integrated marketing communications tool as the digital landscape develops. It can be concluded that young consumers show a high degree of perceived value and low levels of perceived risk due to the use of GSA. This study, therefore, promotes improved understanding among academics, marketers and businesses of search engine advertising among young cohorts of consumers (Generation Y and Z) in a developing country context.

The food industry is continuously developing its online services called food delivery applications (FDAs). This study aims to evaluate FDA's importance–performance and identify strategies to maximize its potential gains from a business partner's perspective.

Data are collected from 208 FDA partners in Indonesia. Importance–performance analysis (IPA) is applied to evaluate the FDA feature and extended the theory of potential gain in customer value (PGCV) to achieve potential gains from FDA business partners.

This study provides a clear and measurable direction for future research to develop FDA performance. Owning customer data, revenue sharing and competitive advantage are the most potential gains from joining the FDA from the business partner perspective.

The respondents are restaurants from the micro, small, and medium enterprises levels. Further research should involve middle to upper level restaurants to discover all business partners' perceptions. This will be very helpful for FDA providers interested in improving the best performance for all their partners.

FDA providers must focus on improving and maintaining the features of owning customer data, revenue sharing, competitive advantage, stable terms and conditions, customer interface, building customer loyalty, online presence, user credit rating, promotion and offers, delivery service and sales enhancement to increase consumer satisfaction and meet the expectations desired by business partners.

This research provides a meaningful theoretical foundation for future work. It extends the theory of PGCV using the value of a partner perspective as a substitute for customer value; hence, the authors call it a potential gain in partner value.

The purpose of this study is to contribute to the debate on the impact of organizational culture and national culture on green supply chain management (GSCM) adoption by empirically testing the developed framework, and ultimately pave the way toward potential areas for future research.

Using survey data from a sample of Moroccan manufacturing firms, 130 responses were collected and analyzed using SPSS 25 and Smart PLS v 3.3.3 software. The paper used a convenience sample, as it is required by the quantitative method, which legitimate making generalization under certain conditions.

The research results indicated that the national culture does not influence the GSCM implementation. The results contradict a number of prior works. As for the second direct effect measured postulated that organizational culture has a direct and significant impact on the GSCM. The results indicate that adhocracy culture, clan culture and hierarchical culture have a positive impact on the implementation of GSCM initiatives. To assess the impact of ownership type on GSCM, we underlined the difference between local and foreign firms. In fact, as argued, the foreign firms are more implementing GSCM initiatives than local firms do. Based on the arguments advanced on prior literature, the firm size does, as expected, exert significant control over the adoption of GSCM initiatives.

The paper here is a starting point to understand how environmental sustainability and culture are interlinked; further research might contribute to this topic by empirically testing the model in similar or different contexts, using different cultural frameworks.

The practical implications for the paper are related to the necessity of adopting adequate organizational culture to build responsible behaviors for GSCM adoption by Moroccan firms. Recognizing the powerful role of organizational culture as a crucial factor responsible for GSCM’s success beyond the well-defined corporate strategies, including market presence and technological advantages, etc.

This paper contributes to the establishment of codependent links between sociology and management fields as it helps to update the social theories present in the operations management area.

To the best of the author’s knowledge, few works have pursued to review and bridge cultural theories with the GSCM implementation.

The COVID-19 pandemic has caused severe challenges to ethnic minorities in the UK. While the experiences of migrants are both complex and varied depending on individuals' social class, race, cultural proximity to the host country and acculturation levels, more in-depth studies are necessary to fully understand how COVID-19 affects specific migrant groups and their health. Taiwanese migrants were selected because they are an understudied group. Also, there were widespread differences in pandemic management between the UK and Taiwan, making this group an ideal case for understanding how their acculturation journey can be disrupted by a crisis.

Qualitative data were collected at two different time points, at the start of the UK pandemic (March/April 2020) and six months on (October/November 2020), to explore migrant coping experiences over time. Theoretically, the authors apply acculturation theory through the lens of coping, while discussing health-consumption practices, as empirical evidence.

Before the outbreak of the pandemic, participants worked hard to achieve high levels of integration in the UK. The pandemic changed this; participants faced unexpected changes in the UK’s sociocultural structures. They were forced to exercise the layered and complex “coping with coping” in a hostile host environment that signalled their new marginalised status. They faced impossible choices, from catching a life-threatening disease to being seen as overly cautious. Such experience, over time, challenged their integration to the host country, resulting in a loss of faith in the UK’s health system, consequently increasing separation from the host culture and society.

It is important to note that the Taiwanese sample recruited through Facebook community groups is biased and has a high level of homogeneity. These participants were well-integrated, middle-class migrants who were highly educated, relatively resourceful and active on social media. More studies are needed to fully understand the impact on well-being and acculturation of migrants from different cultural, contextual and social backgrounds. This being the case, the authors can speculate that migrants with less resource are likely to have found the pandemic experience even more challenging. More studies are needed to fully understand migrant experience from different backgrounds.

Public health policymakers are advised to dedicate more resources to understand migrants' experiences in the host country. In particular, this paper has shown how separation, especially if embraced temporarily, is not necessarily a negative outcome to be corrected with specific policies. It can be strategically adopted by migrants as a way of defending their health and well-being from an increasingly hostile environment. Migrants' home country experience provides vicarious learning opportunities to acquire good practices. Their voices should be encouraged rather than in favour of a surprising orthodox and rather singular approach in the discussion of public health management.

The paper has clear public health policy implications. Firstly, public health policymakers are advised to dedicate more resources to understand migrants' experiences in the host country. Acknowledging migrants' voice is a critical first step to contribute to the development of a fair and inclusive society. Secondly, to retain skilful migrants and avoid a future brain-drain, policymakers are advised to advance existing infrastructure to provide more incentives to support and retain migrant talents in the post-pandemic recovery phase.

This paper reveals how a group of previously well-integrated migrants had to exercise “coping with coping” during the COVID crisis. This experience, over time, challenged their integration to the host country, resulting in a loss of faith in the UK’s health system, consequently increasing separation from the host culture and society. It contributes to the understanding of acculturation by showing how a such crisis can significantly disrupt migrants' acculturation journey, challenging them to re-acculturate and reconsider their identity stance. It shows how separation was indeed a good option for migrants for protecting their well-being from a newly hostile host environment.

As research emerged in terms of how narcissism, a negative or dark trait, has been found to be constructive in enhancing entrepreneurial behaviour, there are mixed results regarding the significance of narcissism in the field of entrepreneurship. Additionally, this previous research has mostly been conducted on student or nascent entrepreneur samples within developed economies. Therefore, the purpose of this paper is to explore how narcissistic traits of established entrepreneurs in an emerging economy context infuence their entrepreneurial behaviour both positively and negatively.

Gioia methodology was applied in the qualitative study by means of in-depth interviews, which allowed for the unpacking of narcissistic traits among established entrepreneurs in South Africa. Four themes emerged from the data, and included insights related to entrepreneurial experience influencing behaviour; business growth linked to personal development; opportunity identification versus loss; and identity separation in relation to authentic identity versus an entrepreneurial identity.

The findings of the paper contribute to creating an understanding of how to hone individual narcissistic traits for positive influences that develop entrepreneurs while also contributing to their business development, opportunity realization and identity. In addition, the findings highlighted a separation between established entrepreneurs’ authentic personality and the inputs that end up resulting in the entrepreneurial personality.

This paper highlights the possibility of narcissism functioning as a business process involved in entrepreneurship rather than a necessary personality trait. An interesting dynamic contributed to what seems to be a constant battle between the authentic identity and the entrepreneur identity, gaining deeper insight surrounding established entrepreneurs’ experiences to survive and, more importantly, thrive as entrepreneurs.

Recent years have seen a meteoric rise in the study of narcissism in entrepreneurship, although little consolidation has occurred in this area. The purpose of this paper is the development of an integrative framework to harmonise the academic discussion and serve as a structured foundation for future research.

The authors conducted an artificial intelligence-aided, structured literature review focused on content analysis of concepts and contexts to map out current findings and research gaps in startup narcissism research.

According to the findings of this study, narcissistic tendencies have the potential to positively influence startup success early on in an entrepreneur's journey, but after a certain point in the process, the influence of narcissism on success becomes predominantly negative.

The research field is currently not very harmonised regarding research measures, research subjects and key research terms. Further research must use a standardised approach to add value to the research body.

Narcissism is a two-sided sword for founders. In the early stages of a company, many of the founder’s tasks can benefit from narcissistic tendencies. In the later stages of a company, that might shift to overwhelmingly negative effects of narcissism.

Methodically, this study is the first one to establish an artificial intelligence component to add value to the results of a review paper to the best of the authors’ knowledge. The results of this study provide a clear framework of entrepreneurial intention, entrepreneurial activity and entrepreneurial performance to give researchers the opportunity of a more differentiated way of organising work.