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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.

A numerical study is performed to investigate flow instability phenomena in a square channel with steady, laminar throughflow. The channel rotates around an axis perpendicular to the channel longitudinal axis. The flow field extends from the channel entrance to a distance of 120 to 600Dh. The range of Reynolds number is Re = 300−2000. The inlet flow velocity is assumed uniform. Surface vorticity intensity is introduced to indicate the variation of vortices. It is revealed that at intermediate Reynolds numbers (680 > Re > 300), the flow is characterized by three vortex patterns: at slow rotation there is one vortex pair; at intermediate rotation a secondary vortex, in addition to the original vortex, emerges near the trailing wall and then breaks down downstream; and at rapid rotation the secondary vortex does not exist with the flow being restabilized to form a single‐pair vortex pattern. At low Reynolds numbers (Re ≤ 300), the flow exhibits a single‐pair vortex pattern, while at high Reynolds numbers (Re ≥ 680), the flow experiences the emergence and breakdown of a secondary vortex, but no restabilization is found with an increase in the rotational speed. It is also disclosed that the variation of the vortices is related to the distance from the inlet.

The purpose of this study is to analyse and explore the characteristics of patent–paper pairs (PPPs) in the field of fuel cells.

The authors used bibliometric analysis to analyse the bibliometric records of PPPs identified from 20,758 papers and 8,112 utility patents between 1991 and 2010.

The findings show that the percentages of papers and patents constituting PPPs were low, but an increasing trend was identified in the absolute number of PPPs. Researchers affiliated with research institutions were the primary contributors to PPPs. Countries with the most papers and patents had the most PPPs, exploiting the advantage of dual knowledge creation. Similar growth trends were observed in the numbers of patents approved and papers published. Patents in PPPs were typically produced earlier than the papers in PPPs. On average, patents were applied for approximately four years before papers were published, and patents were approved only approximately four months before papers were published.

While the study was limited to the PPPs in the field of fuel cells, PPPs analysis can be applied to numerous fields.

PPPs indicate the coactivity of researchers involved in publishing and patenting. Although this coactivity has been studied, few studies have investigated PPPs. This study helps us better understand the characteristics of papers and patents constituting PPPs, changes in the annual numbers of papers and patents constituting PPPs, delays between papers and patents, as well as individuals, institutions and countries producing numerous PPPs.

This paper aims to examine the relationship between the nationality and educational background diversity of directors serving on corporate boards and the firms’ corporate social performance (CSP).

This study measures nationality diversity by directors’ national citizenship and measures educational background diversity by countries from which they earned their undergraduate and post undergraduate degrees. It measures firms’ CSP using the MSCI ESG ratings. The study uses both univariate and multivariate analyses to empirically test the hypotheses.

Using a sample of US firms, the authors find that board nationality diversity and educational background diversity are positively associated with CSP. The findings suggest that improving director nationality diversity and educational background diversity could improve firms’ social performance.

This study shows that the increasing trend of foreign nationals in the US boards could shift the focus of US corporations to be more stakeholder-oriented.

Although coresidence with children when one becomes old is an ideal in Chinese society, the drastic socio-economic development in Taiwan has brought some fundamental changes to living arrangements of the elderly population. The purpose of this paper is to examine the relationship between family living arrangements and elderly health in Taiwan, given the secular trend of more elderly persons choosing to live with their spouse or to live independently.

The authors utilized panel data from the “1989 Survey of Health and Living Status of the Elderly in Taiwan” with follow-ups up to 2007 to examine how living arrangements of the elderly affect the risk of mortality using discrete-time hazard models. The authors stratified the analyses by the elderly’s preference to coreside with children, and examined whether the effects of living arrangement varied by age, controlling for sociodemographics, health status, health behaviors, and social relationships observed at the baseline.

The authors found that both the associations of living arrangements and coresidence preference with that mortality risk were largely weakened when controlling for other variables. Only among respondents expressing preference for coresidence were living arrangements associated with mortality risks, and these effects increased with age. For those who did not intend to live with children, the authors found no evidence suggesting living arrangements were associated with mortality risks. The dynamics of living arrangements among the elderly and elderly care policies in Taiwan are discussed for further research.

To the authors knowledge, no previous research has examined living arrangements and mortality risks with respect to coresidence preference.

This study identifies the factors that influence companies to obtain the B corporation certification. Drawing from institutional isomorphism, gender socialization theory, the ethics of care and social identity theory, the authors examine the impact of geographic locality, product market competitions and owners’ demographic characteristics on a firm’s decision to be a certified B Corporation.

Using two sets of data, a hand-collected sample of 743 small businesses receiving a B Corporation certification between 2007 and 2014 and a sample of 902 firms participating in a B Lab survey from 2011 to 2013, the authors examine factors that influence firms’ decision to obtain the B Corporation and their environment, social and governance (ESG) performance.

Firms in states that are democratic-leaning, have a lower hourly wage rate or have a greater religious population are more likely to be early adopters and leaders of the B Corporation movement than those in other states. On average, states with a higher unemployment rate and more democratic-leaning voters have more B Corporation certified firms in each year and over the years. Additionally, product market competition is positively associated with firms’ likelihood of obtaining B Corporation certification and their ESG scores.

This study brings new insights to the understanding of purpose-driven enterprises and factors that influence firms’ decision to go through the B Corporation verification and certification process.

This study establishes a theoretical foundation that becoming a B Corporation is a corporate social responsibility (CSR) action and shows that existing theories explaining the factors motivating companies to engage in CSR can also be applied to explain firms’ motivation to become B Corporations.

A theoretical study is performed on three‐dimensional, heat transfer and fluid flow in radially rotating heated channels with steady, laminar throughflow. Consideration is given to the channel of different geometry. Both the rotational speed and throughflow rate are varied. The flow is hydrodynamically and thermally developing, with a constant wall heat flux. The velocity‐vorticity method is employed in the formulation and numerical results are obtained by means of a finite‐difference technique. The Nusselt number, friction factor, and temperature and velocity distributions are determined, and the role of the Coriolis force on the entrance‐region transport phenomena is investigated. Results are compared with the existing literature.

Purpose: Despite the significance of filial piety in intergenerational relationships and its important influence on parental health and well-being, few studies have explored the personal meaning of filial piety to older parents. This qualitative study aims to address this question.

Design: Responses to an open-ended question of “What makes a filial child in your view?” from a sample of 432 older parents in a rural Chinese county were collected face-to-face and analyzed using content analysis.

Findings: The personal meaning of filial piety varies. Seven broad themes emerged. These include widely persistent traditional filial piety beliefs (Be obedient, Respect, and Maintain frequent contact and show emotional care), filial piety values similar to filial obligations described in Western cultures (Help older parents when in times of need and Be a good citizen and take good care of themselves and their families), and traditional filial piety norms in the absolute form (Take care of every aspect of the parents’ life and Provide financial and material support to parents). Themes were also compared with dimensions of the intergenerational solidarity model.

Originality: Findings reflect the coexistence of traditional and modern filial values in relation to participants’ interpretation of filial piety, indicating that traditional filial piety beliefs are fading even in one of the least developed areas in China. Implications for interventions enhancing offspring’s filial performance are discussed.

Research limitations: Future studies on the understanding of filial piety from the perspective of offspring are warranted to draw a holistic picture of this topic.

The purpose of this paper is to find the relationship of palaeontology, palaeobotany and coal thickness of Taiyuan Formation during Late Carboniferous – Early Permian Period in Shanxi Province.

This paper selects three regions, namely, Baode, Xishan and Lingchuan, to analyse the distribution characteristics of palaeontology, palaeobotany and variation of coal thickness.

It was found that in a certain period of geological history, palaeontology and palaeobotany play a dominant role in shaping of a coal-bearing basin. Coal seam thickness changes largely from the northwest to the southeast, gradually thinning in Taiyuan Formation.

Palaeontology and palaeobotany play a dominant role in the shaping of a coal-bearing basin.

The purpose of this paper is to investigate the dynamic characteristics of a spiral groove liquid film seal considering the effect of cavitation.

A mathematical model of a spiral groove liquid film seal was established based on the mass-conserving Jakobsson–Floberg–Olsson cavitation boundary condition. The film rupture and film reformation boundaries were assumed to be unchanged under infinitesimal perturbation conditions. Governing equations under steady and perturbed states were solved by the finite element method, and then the dynamic characteristics of the spiral groove liquid film seal were theoretically investigated considering the effect of cavitation.

The results indicate that dynamic coefficients considering cavitation are smaller than those neglecting cavitation. The difference value is consistent with the change in cavitation area. The liquid film seal does not suffer axial instability whether considering cavitation, but its angular instability is more likely to occur when cavitation is considered.

For liquid lubricated non-contacting mechanical seals, the dynamic characteristics considering cavitation are investigated. The results are expected to provide a theoretical basis for improving the design method of liquid film seals.