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Combined defects in ball bearings may be caused during the use or manufacturing process, which can significantly affect their vibration characteristics. The previous defect models in the literature can only describe single defects such as the surface waviness and localized defect. This paper aims to propose an in-depth understanding of radial vibrations of a ball bearing with the combined defect.

A dynamic model for a ball bearing with the combined defect including the surface waviness and localized defect on its races is proposed. The effects of the combined defect sizes on the radial bearing vibrations are investigated. The results from the proposed model considering the combined defect are compared with the available results from the previous methods considering the single defects.

The acceleration amplitude is significantly affected by the surface waviness, localized defect and the combined defect on its races. The effect of the combined defect on the acceleration amplitude is larger than that of the single defect. The amplitude and peak frequency of the spectrum of acceleration for the combined defect increases with the defect sizes. The RMS value of the accelerations for the combined defect increases with the combined defect sizes.

Consequently, the proposed model can predict more accurate and in-depth understanding of the radial vibrations caused by the combined defect in the ball bearing.

The purpose of this paper is to explicate the influence of diverse team on team-level ambidexterity and its curvilinear assessment, and test the mediating role of team reflexivity and the moderating role of shared meta-knowledge in the curvilinear relationship between team diversity and team ambidexterity.

The authors collected multisource and temporally separated data on 206 R&D teams within 28 high-tech firms in Taiwan.

This study found a complex, curvilinear, moderated mediation relationship that functional background diversity has with team ambidexterity. Furthermore, consistent with the notion from categorization-elaboration model, the authors found the curvilinear relationship that functional background diversity has with both team ambidexterity and team reflexivity. Finally, the authors also found that the curvilinear relationship between functional background diversity and team reflexivity was moderated by shared meta-knowledge, such that the positive relationship was strengthened and the negative relationship weakened, in higher shared meta-knowledge in teams rather than lower.

The results demonstrate that team diversity-team ambidexterity relationship is much more complicated than previous works have assumed or suggested. Overall, the authors contribute to a novel understanding about the importance of team diversity in ambidextrous teams by opening the black box of how and when functional background diversity and team ambidexterity.

Prior marketing and hospitality studies have largely ignored the role of corporate social responsibility (CSR) in shaping frontline employees’ customer orientation. This study aims to investigate the impacts of employee perceived CSRs on customer orientation in hotel industry.

Through an onsite data collection from 642 frontline employees of 14 hotels in China, the moderated mediation model that links frontline employees’ perceptions of internal and external CSR to person-organization fit, work engagement and customer orientation were validated with the bootstrapping procedures.

The results reveal that a higher degree of perceived internal and external CSR leads to greater customer orientation through work engagement, and these indirect effects will be stronger with comparatively higher person-organization fit levels.

By clarifying the connection between perceived CSR initiatives and customer-oriented behaviors, this study offers inspiration for hospitality managers to devise, allocate and leverage CSR investments, strategies and practices.

To the best of the authors’ knowledge, this study is the first to verify a moderated mediation model that investigates the impacts of perceived CSRs (i.e. internal vs external) on customer orientation, which not only uncovers some neglected antecedents of customer orientation but also provides a more nuanced insight into perceived CSR-customer orientation linkages.

With the development of machine learning techniques, the artificial intelligence systems such as crowd networks are becoming more autonomous and smart. Therefore, there is a growing demand for developing a universal intelligence measurement so that the intelligence of artificial intelligence systems can be evaluated. This paper aims to propose a more formalized and accurate machine intelligence measurement method.

This paper proposes a quality–time–complexity universal intelligence measurement method to measure the intelligence of agents.

By observing the interaction process between the agent and the environment, we abstract three major factors for intelligence measure as quality, time and complexity of environment.

This paper proposes a calculable universal intelligent measure method through considering more than two factors and the correlations between factors which are involved in an intelligent measurement.

Motivating users to self-disclose online is significant to the long-term development of social media. Therefore, research on emotional disclosure, a significant form of self-disclosure, is required. By developing a stimulus-organism-response model, this study aims to investigate the mechanisms by which the social media environment affects users' online emotional disclosure.

This paper proposes two dimensions of social media environments, the online interpersonal environment (tie strength and network size) and the online information environment (self-reference). They are hypothesized to stimulate users' internal psychological needs (image management and emotional expression) which in turn will influence their emotional disclosure intentions. Using data from 489 users of WeChat Moments, the authors conduct partial least squares analysis to validate the research model.

The findings show that users' intrinsic psychological needs are stimulated by social media environments, but network size is not correlated with the need for emotional expression. The user's need for emotional expression promotes both positive and negative emotional disclosure intentions. The need for image management has a positive impact on positive emotion disclosure intentions but has a negative impact on negative emotion disclosure intentions.

This study contributes to the understanding of online emotional disclosure. It can also help social media managers create efficient plans to encourage users to create content.

The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-04-2022-0245.

The purpose of this study is to investigate the contact models for contact and vibration features of cylindrical roller bearings (CRBs). CRBs are important parts of rotating machinery. The contact deformation between the roller and the raceway is an essential research topic for the CRBs. The contact deformation between the roller and the raceway can greatly affect vibration characteristics and fatigue life of the CRBs. In this investigation, six different methods are adopted to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB.

In this paper, the contact deformations and the contact stiffnesses between the roller and the raceway of a CRB obtained by various well-known empirical methods (Lundberg’s, Palmgren’s, Houpert’s, Cheng’s and Hertzian methods) are directly compared with those by the finite element (FE) method. A two degree-of-freedom (2 DOF) dynamic model of the CRB is applied to investigate the effects of the contact stiffness obtained by different line contact deformation calculation methods on the vibration characteristics, such as the root mean square (RMS), the peak to peak (PTP), the crest factor and the kurtosis of the displacement, velocity and acceleration of the inner raceway.

The computational results show that different calculation methods for the contact deformations between rollers and raceways have significant effects on the vibrations of the CRB. It is found that that the differences of computational results obtained by Palmgren’s and Lundberg’s models with respect to the FE method are smaller than those by the other three methods, i.e. Houpert’s, Cheng’s and Hertzain models. The amplitude and peak frequency of the frequency response functions from Palmgren’s method are much more similar to those from the finite element method. The above results indicate that Palmgren’s method is a better calculation method for predicting the contact deformations and dynamics of the CRBs.

This work adopts six different methods to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB. Moreover, a vibration model of a CRB is used to investigate the effect of contact stiffness obtained by the above methods on the vibrations of the CRB. The works can give some guidance for the accurate analytical method for calculating the contact deformations between rollers and raceways and the vibrations of the CRB.

This paper aims to propose a method that can directly print low-melting-point alloy In61Bi26Sn9Ga4 into a variety of macroscopic 3D structures at room temperature via adhesion mechanism.

In the first section, the principle of the direct printing system is described. As process parameters and material properties have both geometric and physical significance to printing, the approach the authors take is to study the relationships between key parameters and ultimate printed dimension. The surface tension of the fusible alloy is measured under different temperature ranges.

The interaction between the initial standoff distance and the geometry of the first layer is critically important for the adhesion of the liquid metal to the substrate and metal deposition. The characterization of the layer stacking in the direct printing process, stability ranges of the layer thickness and printing speed are also demonstrated. The direct printing system is suitable for making 3D structures with low-melting-point alloy under the summarized range of printing conditions.

This study may arouse big public attention among society.

This study shows possibilities of manufacturing macroscopic 3D metal objects by continuously depositing molten alloy with low viscosity and high surface tension around room temperature. This study provides a supplement to realize compound printing with metal and nonmetal materials together for building terminal functional devices in a low cost and efficient way.