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The purpose of this paper is to study the effects of surface roughness on the lubrication performances of the linear rolling guide, which provides theoretical guidance for its lubrication design.

The two-variable Weierstrass–Mandelbrot function is used to represent the random and multi-scale characteristics of the rough surface topography. The elastohydrodynamic lubrication (EHL) model of contact between the steel ball and raceway is built. The full numerical solutions of the pressure and film thickness are obtained by using the multi-grid technique.

The presence of surface roughness can cause the random fluctuations of the pressure and film thickness, and the fluctuations can become more dramatic for the rougher surfaces. It is also found that the film characteristics can be influenced significantly by the working conditions, such as the load, velocity and ambient viscosity of lubricants.

Characterization of surface topographies regarding EHL problems in the past studies cannot reflect random and multi-scale characteristics. In this paper, the fractal-based method is introduced to analysis of the point-contact micro-EHL. It reveals the mechanism and law of contact lubrication influenced by the fractal surface roughness and enriches the lubrication principle and method of the linear rolling guide.

This paper aims to predict the dynamic behaviors of contact between the steel ball and raceway in the elastohydrodynamically lubricated ball linear guide, thus providing a guidance for lubrication design for ball linear guide.

Based on the point contact elastohydrodynamic lubrication (EHL) theory, the free vibration model of contact pair is presented to qualitatively analyze the effect of vibration on the film characteristics. The models of the film stiffness and damping coefficient under the EHL condition are built to investigate the effects of the working conditions on the dynamic parameters. The full numerical solutions are obtained using the multigrid technique.

It is found that there exists damping from the decay of oscillations of the pressure and film thickness in the lubricated ball linear guide. Furthermore, the working conditions of the high load or low velocity can lead to the increase in the film stiffness in the steel ball-raceway contact, but there is a reverse variation trend for the film damping coefficient.

The contact pair has been usually treated as dry in past studies on dynamics of the ball linear guide, and the damping is neglected. This research considers the actual lubrication and working conditions and predicts the dynamic behaviors of contact pair.

The purpose of this paper is to explore the effect of surface roughness characterized by fractal geometry on squeeze film damping characteristics in damper of the linear rolling guide, which has not been studied so far.

The stochastic model of film thickness between rail and damper is established by using the two-variable Weierstrass–Mandelbrot function defining multi-scale and self-affinity properties of the rough surface topography. The stochastically averaged Reynolds equation is solved by using the variables separation method to further derive the film pressure distribution, the damping coefficient, the damping force and squeeze film time. The effect of surface roughness on squeeze film damping characteristics of the damper is analyzed and discussed through simulation.

By comparing cases of the rough surface for different fractal parameters and the smooth surface, it is shown that for the isotropic roughness structure, the presence of surface roughness of the damper decreases the squeeze film damping characteristics. It is found that roughness effect on the damping coefficient is associated with the film thickness. In addition, the vibration amplitude effect is negligible for the damper of the linear rolling guide.

To investigate the random surface roughness effect, the rough surface topography of damper of the linear rolling guide is characterized by using the fractal method instead of the traditional mathematical statistics method.

The purpose of this study is to investigate the antecedents and the conditions of coopetition at the inter-organizational level.

This study is based on survey research methodology and analyzes the data from 138 companies regarding the antecedents and the conditions of their coopetition.

The results indicate that the interdependence between partners (i.e. the antecedent) positively affects interfirm coopetition, and that this relationship is contingent on the joint occurrence of opportunism (a behavioral condition) and technology uncertainty (a contextual condition). Specifically, highly interdependent firms are more likely to be involved in a coopetitive relationship when both opportunism and technology uncertainty are high. Interestingly, the authors’ data also show that opportunism or technology uncertainty alone may not be adequate in moderating the interdependence–coopetition relationship.

This study contributes to the current literature in two meaningful ways. First, it empirically examines interdependence as a potential antecedent of interfirm coopetition. Second, it improves our understanding of the behavioral and contextual conditions that facilitate the formation of coopetitive relationships by examining the moderating roles of opportunisms and technology uncertainty in the relationship between interdependence and interfirm coopetition. The limitations of this study lie in its confined method of cross-sectional survey from the focal firm’s perspective. Future research may advance beyond this study through experimental and/or longitudinal research designs.

This study provides managers with two important practical insights in coopetition management. First, the findings suggest a two-step approach to help a firm assess and manage the level of coopetition in its relationship with a business partner. In addition, the findings provide a counterintuitive suggestion to managers that the joint conditions of high opportunism and high technology uncertainty indeed prime the relationship for the rise of coopetition, provided that managerial efforts are made to somewhat increase the level of interdependence in the relationship.

Despite the growing number of studies on coopetition, research still lacks knowledge about the antecedents and the conditions of inter-organizational coopetition, and this study aims to fill this gap.

The purpose of this paper is to examine the effect of biased technology on employment distribution and labor status in income distribution of China. It also testifies a threshold effect of the capital per labor and employment distribution on labor status from biased technology.

This paper presents a normalized supply-side system of three equations to measure the bias of technology in China. Linear and threshold regressions approaches are applied over cross-province panel data to investigate the influence which biased technology has on labor status under different capital per labor and employment distribution regimes.

This paper empirically shows that technology has been mostly capital-biased in China. The regression results indicate that capital-biased technology impairs labor income status and tend to modify employment distribution and labor income between industries. Furthermore, it reveals the threshold effect of capital per labor and employment distribution on the relationship between biased technology and labor status.

This paper extends the literature by explaining labor status from the perspective of biased technology and the effect of inter-industry employment distribution in China. It further explores the asymmetric effect of biased technology on labor productivity and income, which promotes inter-industry labor mobility and modifies employment distribution. This paper highlights the implications of this explanation for labor relations and human resource management.

This study aims to examine empirically the existence of four classical and four emerging buyer–supplier relationship (BSR) types and how they differ in terms of behavioral dynamics and performance measures.

This study uses an online survey to collect data from 371 purchasing managers in the USA.

A cluster analysis statistically supports the existence of five of these eight BSR types, including strategic/bilateral partnership, market/discrete, supplier-led collaboration, captive supplier/buyer dominant and captive buyer/supplier dominant BSRs. Further, ANOVA tests show that these five BSRs differ in terms of behavioral outcomes and performance measures.

This study is based on a cross-sectional survey so it cannot examine how these BSR types may evolve over time, and it is not suitable to examine some rare types of BSRs. In addition, this study does not consider contextual factors that may moderate the influence of BSR types on the behavioral dynamics and performance measures.

Managers should consider the potential to be able to develop and enhance a strategic/bilateral relationship with their supply chain partners, which in at least some circumstances can lead to superior performance results. Similar observations can be made with respect to supplier-led and, to a lesser degree, buyer-led collaboration.

Most existing research of the BSR types is largely a product of theoretical classifications, and there is also a lack of research of their performance implications. This study fills these gaps in the literature.

With the yearly increase of mileage and passenger volume in China's high-speed railway, the problems of traditional paper railway tickets have become increasingly prominent, including complexity of business handling process, low efficiency of ticket inspection and high cost of usage and management. This paper aims to make extensive references to successful experiences of electronic ticket applications both domestically and internationally. The research on key technologies and system implementation of railway electronic ticket with Chinese characteristics has been carried out.

Research in key technologies is conducted including synchronization technique in distributed heterogeneous database system, the grid-oriented passenger service record (PSR) data storage model, efficient access to massive PSR data under high concurrency condition, the linkage between face recognition service platforms and various terminals in large scenarios, and two-factor authentication of the e-ticket identification code based on the key and the user identity information. Focusing on the key technologies and architecture the of existing ticketing system, multiple service resources are expanded and developed such as electronic ticket clusters, PSR clusters, face recognition clusters and electronic ticket identification code clusters.

The proportion of paper ticket printed has dropped to 20%, saving more than 2 billion tickets annually since the launch of the application of E-ticketing nationwide. The average time for passengers to pass through the automatic ticket gates has decreased from 3 seconds to 1.3 seconds, significantly improving the efficiency of passenger transport organization. Meanwhile, problems of paper ticket counterfeiting, reselling and loss have been generally eliminated.

E-ticketing has laid a technical foundation for the further development of railway passenger transport services in the direction of digitalization and intelligence.

This paper aims to examine how a firm’s capability affects its political networking in emerging economies and how the institutional environment influences the relationship between a firm’s capability and its political networking.

The authors test the theoretical model by analyzing a database from a World Bank survey in China.

The results show a nonlinear (U-shaped) relationship between a firm’s capability and its efforts in political networking. The relationship between a firm’s capability and political networking is contingent on the institutional environment, as reflected in institutional development and industry regulation.

This study elucidates political networking in emerging economies and contributes to research on corporate political strategy.

The relationship between online reviews and purchase intention has been studied in previous research. However, there was little knowledge about the effect of information quality and the social presence of online reviews on purchase intention based on the stimulus-organism-response (S-O-R) framework. The purpose of this study is to explore the intrinsic relationship between the stimulus (perceived information quality and social presence) generated from online reviews and the response (purchase intention).

This study developed a research model by applying the S-O-R framework to test the proposed hypotheses. A combination of a web-based experiment and an online survey was employed to collect data. Hypotheses were empirically tested using Smart PLS.

The PLS analysis shows that both perceived information quality and the social presence of online reviews positively affect trust. Moreover, satisfaction with online reviews affects purchase intention, whereas trust has a positive impact on satisfaction, playing a mediating role between two stimuli and satisfaction. Besides, perceived information quality of positive online reviews is found to have a more significant impact on trust, satisfaction and purchase intention.

The results of this study are of great value for expanding both theoretical research and practical applications of online reviews in relation to purchase intention. This study with a new research model reveals the understanding of how the purchase intention will be motivated by online reviews. Meanwhile, the moderating effects and the mediating effects are also discussed.

Online reviews presented in the format of multimedia information, such as pictures and videos, continue to emerge, but whether the richness of multimedia information can enforce the quality of online reviews has remained uncertain. The purpose of this paper is to examine the differences in the perceived information quality of online reviews, based on the information richness theory, emotional polarity and product type.

This is a Web-based experiment in which 12 groups constructed at different levels of these three factors were designed for the purpose of obtaining data.

The study results show that under different positive and negative emotional polarities, different information richness and product types have different effects on perceived information quality; for different product types, positive and negative emotional polarity have different effects on perceived information quality. For “search” products, the perceived information quality of online reviews with low information richness is high; under different information richness, different emotional polarity and product types have different effects on perceived information quality.

This paper has important practical significance for the management of e-commerce platforms for online reviews.

This paper on the perceived information quality of online reviews puts more focus on the formal features of online reviews and aims to discover the relationships between different directions for perceived information quality under the impact of interaction of formats, emotional polarity and product type. The study hopes to further strengthen the application of the information richness theory in the field of online reviews research and to measure perceived information quality from a variety of aspects.