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Under the high-speed operating conditions, the effects of wheelset elastic deformation on the wheel rail dynamic forces will become more notable compared to the low-speed condition. In order to meet different analysis requirements and selecting appropriate models to analyzing the wheel rail interaction, it is crucial to understand the influence of wheelset flexibility on the wheel-rail dynamics under different speeds and track excitations condition.

The wheel rail contact points solving method and vehicle dynamics equations considering wheelset flexibility in the trajectory body coordinate system were investigated in this paper. As for the wheel-rail contact forces, which is a particular force element in vehicle multibody system, a method for calculating the Jacobian matrix of the wheel-rail contact force is proposed to better couple the wheel-rail contact force calculation with the vehicle dynamics response calculation. Based on the flexible wheelset modeling approach in this paper, two vehicle dynamic models considering the wheelset as both elastic and rigid bodies are established, two kinds of track excitations, namely normal measured track irregularities and short-wave irregularities are used, wheel-rail geometric contact characteristic and wheel-rail contact forces in both time and frequency domains are compared with the two models in order to study the influence of flexible wheelset rotation effect on wheel rail contact force.

Under normal track irregularity excitations, the amplitudes of vertical, longitudinal and lateral forces computed by the flexible wheelset model are smaller than those of the rigid wheelset model, and the virtual penetration and equivalent contact patch are also slightly smaller. For the flexible wheelset model, the wheel rail longitudinal and lateral creepages will also decrease. The higher the vehicle speed, the larger the differences in wheel-rail forces computed by the flexible and rigid wheelset model. Under track short-wave irregularity excitations, the vertical force amplitude computed by the flexible wheelset is also smaller than that of the rigid wheelset. However, unlike the excitation case of measured track irregularity, under short-wave excitations, for the speed within the range of 200 to 350 km/h, the difference in the amplitude of the vertical force between the flexible and rigid wheelset models gradually decreases as the speed increase. This is partly due to the contribution of wheelset’s elastic vibration under short-wave excitations. For low-frequency wheel-rail force analysis problems at speeds of 350 km/h and above, as well as high-frequency wheel-rail interaction analysis problems under various speed conditions, the flexible wheelset model will give results agrees better with the reality.

This study provides reference for the modeling method of the flexible wheelset and the coupling method of wheel-rail contact force to the vehicle multibody dynamics system. Furthermore, by comparative research, the influence of wheelset flexibility and rotation on wheel-rail dynamic behavior are obtained, which is useful to the application scope of rigid and flexible wheelset models.

Websites, search engines, recommender systems, artificial intelligence and digital libraries have the potential to support serendipity for unexpected interaction with information and ideas which would lead to favored information discoveries. This paper aims to explore the current state of research into serendipity particularly related to information encountering.

This study provides bibliometric review of 166 studies on serendipity extracted from the Web of Science. Two bibliometric analysis tools HisCite and RStudio (Biblioshiny) are used on 30 years of data. Citation counts and bibliographic records of the papers are assessed using HisCite. Moreover, visualization of prominent sources, countries, keywords and the collaborative networks of authors and institutions are assessed using RStudio (Biblioshiny) software. A total of 166 papers on serendipity were found from the period 1989 to 2022, and the most influential authors, articles, journals, institutions and countries among these were determined.

The highest numbers of 11 papers were published in the year 2019. Makri and Erdelez are the most influential authors for contributing studies on serendipity. “Journal of Documentation” is the top-ranking journal. University College London is the prominent affiliation contributing highest number of studies on serendipity. The UK and the USA are the prominent nations contributing highest number of research. Authorship pattern for research on serendipity reveals involvement of single author in majority of the studies. OA Green model is the most preferred model for archiving of research articles by the authors who worked on serendipity. In addition, majority of the research outputs have received a citation ranging from 0 to 50.

To the best of the authors’ knowledge, this paper may be the first bibliometric analysis on serendipity research using bibliometric tools in library and information science studies. The paper would definitely open new avenues for other serendipity researchers.

This paper aims to examine the effect of dividend regulation on cost stickiness (i.e. the asymmetric change in firm expense between sales increase and sales decrease) and explore the underlying mechanism.

Based on the quasi-natural experiment of the Guideline for Dividend Policy of Listed Companies issued by the Shanghai Stock Exchange (SSE) in 2013, the authors employ a difference-in-difference model to investigate the impact of dividend regulation on cost stickiness.

The authors find that the cost stickiness of treatment group firms has decreased significantly when compared with control group firms after the dividend regulation. Moreover, this effect is more pronounced among firms in lower marketization regions, in lower competition industries and those with less analyst coverage and lower cash flow levels. Further analyses show that dividend regulation reduces the cost stickiness of firms by mitigating agency problems. Finally, the conclusion holds after several robust tests, including controlling for firm fixed effect, propensity score matching (PSM), placebo test and reconstruction of expense variable.

This paper confirms that dividend regulation serves an important role in corporate governance, which reduces firms' agency costs and thereby decreases cost stickiness. The conclusions shed light on the dividend policies of listed companies and capital market regulation in the future.

The purpose of this paper is to provide the theoretical insights with regard to the green purchasing intention–behavior gap and the role played by social media influences in abating this gap. This paper takes into consideration a wider aspect with regard to the antecedents of behavioral intention through personal and social identities in place of the antecedents presented in the theory of planned behavior and social-identity theory. Furthermore, as the theories lack an explanation of how to reduce the intention–behavior gap, this paper also argues the source credibility model (SCM) in explaining the impact that social media influences can have on the behavioral gap.

Hypothetical deductive method is proposed for this concept paper under the positivism research paradigm.

Not applicable as this is a concept paper. However, the paper discusses the theoretical and managerial implications.

This is a concept paper. Yes this paper discusses the theoretical, managerial, and social/ecological implications.

This paper highlights the relevance of consumers' personal and social identities when consumers make purchasing decisions regarding green products. How managers can make marketing strategies, based on credibility model, involving social media influences as product endorsers and ambassadors, as well as the policy makers to design products, earmark consumer behavior and to conduct marketing campaigns in time to come.

As to how policies can be designed and adopted for bio-based economies where sustainability and circularity are given priority and to increase the attention of businesses moving toward sustainable practices.

Original thought developed based on research, theoretical and market gaps.

The purpose of this paper is to explore and test the motivation behind the evolution of China’s vast network of partnerships around the globe since the end of the Cold War.

After combing through 24 types of partnerships with 78 countries, the authors empirically tested four hypotheses using data from Correlates of War and World Bank.

The analysis indicates that China’s choice to build such an elaborate network is not random. On the contrary, it is largely determined by three factors: the need to counter the US pressure; the necessity of maintaining peace and stability along its borders and achieving the long-term goal of modernization.

The research is among the first attempts to comprehensively test the possible motivations behind China’s partnership building efforts and provides a stepping stone for analyzing this important aspect of China’s foreign policy.

Ron Seaver is in a unique position within the sport industry. He has worked on both sides of the sponsorship business, selling sponsorships for teams and assisting corporations in securing productive sponsorship. In his current role as President and CEO of Seaver Marketing Group, Ron is working to bring all parties in the sponsorhip industry together. Here he talks to Dr David Stotlar, of the University of Northern Colorado, sharing his experience and his insights.