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The paper presents a mathematical problem involving quasistatic contact between a thermo-electro-viscoelastic body and a lubricated foundation, where the contact is described using a version of Coulomb’s law of friction that includes normal damped response conditions and heat exchange with a conductive foundation. The constitutive law for the material is thermo-electro-viscoelastic. The problem is formulated as a system that includes a parabolic equation of the first kind for the temperature, an evolutionary elliptic quasivariational inequality for the displacement and a variational elliptic equality for the electric stress. The author establishes the existence of a unique weak solution to the problem by utilizing classical results for evolutionary quasivariational elliptic inequalities, parabolic differential equations and fixed point arguments.

The author establishes a variational formulation for the model and proves the existence of a unique weak solution to the problem using classical results for evolutionary quasivariational elliptic inequalities, parabolic difierential equations and fixed point arguments.

The author proves the existence of a unique weak solution to the problem using classical results for evolutionary quasivariational elliptic inequalities, parabolic difierential equations and fixed point arguments.

The author studies a mathematical problem between a thermo-electro-viscoelastic body and a lubricated foundation using a version of Coulomb’s law of friction including the normal damped response conditions and the heat exchange with a conductive foundation, which is original and requires a good understanding of modeling and mathematical tools.

With the help of multi-body dynamics software UM, the paper uses Kik–Piotrowski model to simulate wheel-rail contact and Archard wear model for rail wear.

The CRH5 vehicle-track coupling dynamics model is constructed for the wear study of rails of small radius curves, namely 200 and 350 m in Guangzhou East EMU Depot and those 250 and 300 m radius in Taiyuan South EMU Depot.

Results show that the rail wear at the straight-circle point, the curve center point and the circle-straight point follows the order of center point > the circle-straight point > the straight-circle point. The wear on rail of small radius curves intensifies with the rise of running speed, and the wearing trend tends to fasten as the curve radius declines. The maximum rail wear of the inner rail can reach 2.29 mm, while that of the outer rail, 10.11 mm.

With the increase of the train passing number, the wear range tends to expand. The rail wear decreases with the increase of the curve radius. The dynamic response of vehicle increases with the increase of rail wear, among which the derailment coefficient is affected the most. When the number of passing vehicles reaches 1 million, the derailment coefficient exceeds the limit value, which poses a risk of derailment.

The purpose of this paper is to show that the droplet impact phenomenon is important for the advancement of industrial technologies in many fields such as spray cooling and ink jet printing. Droplet bouncing on the nonwetting surfaces is a special phenomenon in the impact process which has attracted lots of attention.

In this work, the authors fabricated two kinds of representative nonwetting surfaces including superhydrophobic surfaces (SHS) and a slippery liquid-infused porous surface (SLIPS) with advanced UV laser processing.

The droplet bouncing behavior on the two kinds of nonwetting surfaces were compared in the experiments. The results indicate that the increasing Weber number enlarges the maximum droplet spreading diameter and raises the droplet bounce height but has no effect on contact time.

In addition, the authors find that the topological SHS and SLIPS with the laser-processed microwedge groove array produce asymmetric droplet bouncing with opposite offset direction. Microdroplets can be continuously transported without any additional driving force on such a topological SLIPS. The promising method for manipulating droplets has potential applications for the droplet-based microfluidic platforms.

As the global presence of Chinese firms grows, increasing numbers of Chinese managers are working abroad as expatriates. However, little attention has been paid to such Chinese expatriate managers and their leadership challenges in an inter-cultural context, especially across a large cultural distance. To fill the gap in the literature concerning the leadership challenges for expatriate managers in an inter-cultural context, the purpose of this paper is to elucidate the leadership styles of Chinese expatriate managers from the perspectives of three traditional Chinese philosophies (i.e. Confucianism, Taoism, and Legalism) in the inter-cultural context of the Netherlands.

The data for this qualitative study were collected via semi-structured, open-ended, narrative interviews with 30 Chinese expatriate managers in the Netherlands.

The results clearly show that the leadership style of Chinese expatriate managers is deeply rooted in the three traditional Chinese philosophies of Confucianism, Taoism, and Legalism, even in an inter-cultural context. Specifically, the study reveals two salient aspects of how Chinese expatriate managers frame and interact with a foreign cultural context from the perspectives of traditional Chinese philosophies. First, the Chinese expatriate managers reported an initial cultural shock related to frictions between the foreign cultural context and Confucianism or Taoism, but less so in the case of Legalism. Second, the Chinese expatriate managers also reported that their interactions with the Dutch culture are best described as a balance between partial conflict and partial complementarity (thus, a duality). In this sense, the leadership style of Chinese expatriate managers is influenced jointly by the three traditional Chinese philosophies and certain elements of the foreign cultural context. This is consistent with the Chinese perspective of yin-yang balancing.

This study is among the first to offer a more nuanced and highly contextualized understanding of leadership in the unique case of expatriate managers from an emerging market (e.g. China) in an advanced economy (e.g. the Netherlands). The authors call for more research to apply the unique perspective of yin-yang balancing in an inter-cultural context. The authors posit that this approach represents the most salient implication of this study. For practical implications, the authors argue that expatriate leaders should carefully manage the interplay between their deep-rooted home-country philosophies and their salient host-country culture. Reflecting on traditional philosophies in another culture can facilitate inter-cultural leadership training for Chinese expatriates.

This paper aims to obtain the evolution law of dynamic performance of CR400BF electric multiple unit (EMU).

Using the dynamic simulation based on field test, stiffness of rotary arm nodes and damping coefficient of anti-hunting dampers were tested. Stiffness, damping coefficient, friction coefficient, track gauge were taken as random variables, the stochastic dynamics simulation method was constructed and applied to research the evolution law with running mileage of dynamic index of CR400BF EMU.

The results showed that stiffness and damping coefficient subjected to normal distribution, the mean and variance were computed and the evolution law of stiffness and damping coefficient with running mileage was obtained.

Firstly, based on the field test we found that stiffness of rotary arm nodes and damping coefficient of anti-hunting dampers subjected to normal distribution, and the evolution law of stiffness and damping coefficient with running mileage was proposed. Secondly stiffness, damping coefficient, friction coefficient, track gauge were taken as random variables, the stochastic dynamics simulation method was constructed and applied to the research to the evolution law with running mileage of dynamic index of CR400BF EMU.

Many developing countries are pursuing policies that foster international financial integration after decades of financial repression. Greater access to foreign financial markets may have both positive and negative impact on the performance of the economy. One of the concerns of international financial integration is macroeconomic volatility which may affect both monetary and real sectors. Zimbabwe has chosen to pursue a financial liberalization strategy in the form of imperfect financial integration following periods of excessive domestic shocks. An upsurge of capital flows since the epic of economic crisis in the 2000s has been observed with varying macroeconomic impacts. This study empirically examines the impact of partial international financial integration on the volatility of macroeconomic variables.

The study utilized an ARDL Model suggested by Pesaran et al., (2003) which is appropriate for short time periods.

The results show that financial integration has a negative effect on output volatility while insignificant on consumption volatility.

The study recommends that the country should gradually liberalize the capital account and properly sequence financial development reforms in order to minimize losses from global financial integration.

The study used time series for Zimbabwe during a period of external imbalance, repeated economic cycles, sudden stops in capital flows and limited scope of imperfect financial integration. Findings in such an economy will be a referral for policymakers in other economies that would want to pursue international financial integration.

It is quite universal for high-speed turnouts to be exposed to the wear of the stock rail of the switch rail during the service process. The wear will cause the change of railhead profile and the relative positions of the switch rail and the stock rail, which will directly affect the wheel–rail contact state and wheel load transition when a train passes the turnout and will further impose serious impacts on the safety and stability of train operation. The purpose of this paper is to provide suggestions for wear management of high-speed turnout.

The actual wear characteristics of switch rails of high-speed turnouts in different guiding directions were studied based on the monitoring results on site; the authorized wear limits for the switch rails of high-speed turnout were studied through derailment risk analysis and switch rail strength analysis.

The results show that: the major factor for the service life of a curved switch rail is the lateral wear. The wear characteristics of the curved switch rail of a facing turnout are significantly different from those of a trailing turnout. To be specific, the lateral wear of the curved switch rail mainly occurs in the narrower section at its front end for a trailing turnout, but in the wider section at its rear end when for a facing turnout. The maximum lateral wear of a dismounted switch rail from a trailing turnout is found on the 15-mm wide section and is 3.9 mm, which does not reach the specified limit of 6 mm. For comparison, the lateral wear of a dismounted switch rail from a facing turnout is found from the 35-mm wide section to the full-width section and is greater than 7.5 mm, which exceeds the specified limit. Based on this, in addition to meeting the requirements of maintenance rules, the allowed wear of switch rails of high-speed turnout shall be so that the dangerous area with a tangent angle of wheel profile smaller than 43.6° will not contact the switch rail when the wheel is lifted by 2 mm. Accordingly, the lateral wear limit at the 5-mm wide section of the curved switch rail shall be reduced from 6 mm (as specified) to 3.5 mm.

The work in this paper is of reference significance to the research on the development law of rail wear in high-speed turnout area and the formulation of relevant standards.

Cannabis as a recreational drug is prohibited in Nigeria. Consequently, the open use of cannabis attracts both formal and informal sanctions. As such, there is much stigma on users' faces across social spaces. This has led to innovations in drug use. Recently, non-medical use of tramadol has been rising across each of the gender categories. This study aims to understand (1) tramadol use prompts, (2) the sudden surge in gendered recreational use of tramadol and (3) the gendered challenges of recreational tramadol use among Nigerian university students.

Data were collected between December 2021 and October 2022. The researcher conducted 20 semi-structured interviews, with participants chosen purposefully from acquaintances and others selected through chain referral. The selection criteria included knowledge of a particular tramadol tablet and willingness to participate. This study got ethical approval from the Anambra State Ministry of Health (Ref: MH/AWK/M/321/354) and oral consent was obtained before the interviews. The participants were assured of confidentiality. The interviews were conducted in English (the formal Nigerian language) and lasted between 30 and 65 min. The data collected were transcribed and coded manually, and themes generated.

Findings suggest that peer pressures accounted for entry-level drug use. However, cannabis-related stigma is attributed to the surge in tramadol use across gender categories. Furthermore, academic pressure and sexuality are major reasons for tramadol use. The challenges associated with tramadol use include headaches and addiction.

This study, to the best of the author’s knowledge, presents alternative data on the surge in tramadol use among Nigerian university students.

The purpose of this paper is to examine peer-to-peer sharing platform business models, their sources of competitive advantage, and the roles, motivations and behaviors of key actors in their ecosystems.

This paper uses a conceptual approach that is rooted in the service, tourism and hospitality, and strategy literature.

First, this paper defines key types of platform business models in the sharing economy anddescribes their characteristics. In particular, the authors propose the differentiation between sharing platforms of capacity-constrained vs capacity-unconstrained assets and advance five core properties of the former. Second, the authors contrast platform business models with their pipeline business model counterparts to understand the fundamental differences between them. One important conclusion is that platforms cater to vastly more heterogeneous assets and consumer needs and, therefore, require liquidity and analytics for high-quality matching. Third, the authors examine the competitive position of platforms and conclude that their widely taken “winner takes it all” assumption is not valid. Primary network effects are less important once a critical level of liquidity has been reached and may even turn negative if increased listings raise friction in the form of search costs. Once a critical level of liquidity has been reached, a platform’s competitive position depends on stakeholder trust and service provider and user loyalty. Fourth, the authors integrate and synthesize the literature on key platform stakeholders of platform businesses (i.e. users, service providers, and regulators) and their roles and motivations. Finally, directions for further research are advanced.

This paper helps platform owners, service providers and users understand better the implications of sharing platform business models and how to position themselves in such ecosystems.

This paper integrates the extant literature on sharing platforms, takes a novel approach in delineating their key properties and dimensions, and provides insights into the evolving and dynamic forms of sharing platforms including converging business models.