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Inspired by the high-friction performance of the soft toe pads of tree frogs, this study aims to investigate the effect of elastic deformation on the lubrication properties of squeezing films inside soft tribocontacts with microstructured surface under wet conditions.

A one-dimensional hydrodynamic extrusion model was used to study the film lubrication characteristics of conformal contact. The lubrication characteristics of the extruded film, including load-carrying capacity, liquid flow and surface elastic deformation, were obtained through the simultaneously iterative solution of the fluid-governing and deformation equations.

The results show that the hydrodynamic pressure is approximating parabolically and symmetrically distributed in the contact area, and the peak value appears in the center of the extrusion surface. Elastic deformation increases the thickness of the liquid film, weakens the bearing capacity and homogenizes the liquid flow rate of inside soft friction contact. The magnitude of this effect greatly increases as the initial liquid film thickness decreases. Moreover, the elastic deformation directly affects the average film thickness of the extrusion contact. Narrow and shallow microchannels are found to result in a more prominent elastic deformation on the microstructured soft surface.

These results present a design for soft tribocontacts suitable for submerged or wet environments involving high friction, such as wiper blades, in situ flexible electrons and underwater robots.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-02-2024-0049/

This paper aims to investigate the squeeze film lubrication properties of hexagonal patterned surface inspired by the epidermis structure of tree frog’s toe pad and numerically explore the working mechanism of hexagonal micropillar during the acquisition process of high adhesive and friction for wet contacts.

A two-dimensional elastohydrodynamic numerical model is employed for the squeezing contacts. The pressure distribution, load carrying capacity and liquid flow rate of the squeeze film are obtained through a simultaneous solution of the two-dimensional Reynolds equation and elasticity deformation equations.

Higher pressure is found to be longitudinally distributed across individual hexagonal pillar, with pressure peak emerging at the center of hexagonal pillar. Expanding the area density and shrinking the channel depth or initial film thickness will improve the magnitude of squeezing pressure. Relatively lower pressure is generated inside interconnected channels, which reduces the load carrying capacity of the squeeze film. Meanwhile, the introduction of microchannel is revealed to downscale the total mass flow rate of squeezing contacts.

This paper provides a good proof for the working mechanism of surface microstructures during the acquisition process of high adhesive and friction for wet contacts.

The problem of urban drainage has become more serious with the rapid development of urban construction. The idea of combining geographic information system (GIS) technology with flood control in solving the urban drainage problem has received increasing attention. The idea and process of GIS as the key technology in vertical planning were analyzed in this study based on the GIS technology characteristics. This paper presents the new idea of integrating flood control and drainage mode into vertical planning and the optimization method in vertical planning. Taking the vertical planning of the north shore of Xiaoqing River in Ji'nan as an example, the model of the present scenario and the corresponding terrain model of the different flood control drainage standards were established. The standard model of the flood control and drainage of Xiaoqing River was determined through comparison. The relationship between vertical planning, flood control, and drainage mode was analyzed and optimized on the basis of the practical engineering results. Improving the optimization measures can result in the good convergence of vertical planning and drainage content, which is conducive to the development of urban flood control.

The purpose of this paper is to examine the impact on employee voice from formal vs informal sources of procedural justice: group responsiveness and interactional justice, and to test how this impact may vary according to employees’ traditionality.

Dyadic data were collected from 261 employees and their supervisors. Results of the analyses offered support for the hypothesized moderated mediation model where group responsiveness and interactional justice would influence employee voice through enhanced organization-based self-esteem, and where such influence would be moderated by traditionality.

The findings showed that when there was a high level of group responsiveness, low traditionalists spoke up more, but when there was a high level of interactional justice, high traditionalists spoke up more.

By adopting the group engagement model, this study presented an alternative to the conventional perspective from uncertainty management theory about justice and voice, and tended to the neglect of fairness as an antecedent of voice by investigating how employees’ engagement in voice can be affected by their experience with different sources of procedural fairness information.

X-ray pulsar navigation (XPNAV) is an autonomous celestial navigation technology for deep space missions. The error in the pulse time of arrival used in pulsar navigation is large for various practical reasons and thus greatly reduces the navigation accuracy of spacecraft near the Earth and in deep space. This paper aims to propose a novel method based on ranging information that improves the performance of XPNAV.

This method replaces one pulsar observation with a satellite observation. The ranging information is the difference between the absolute distance of the satellite relative to the spacecraft and the estimated distance of the satellite relative to the spacecraft. The proposed method improves the accuracy of XPNAV by combining the ranging information with the observation data of two pulsars.

The simulation results show that the proposed method greatly improves the XPNAV accuracy by 70% compared with the conventional navigation method that combines the observations of three pulsars. This research also shows that a larger angle between the orbital plane of the satellite and that of the spacecraft provides higher navigation accuracy. In addition, a greater orbital altitude difference implies higher navigation accuracy. The position error and ranging error of the satellite have approximately linear relationships with the navigation accuracy.

The novelty of this study is that the satellite ranging information is integrated into the pulsar navigation by using mathematical geometry.

The purpose of this paper is to investigate the tribological performance of Cr₃C₂–NiCr–Mo–BaF₂ composite sliding against a Si₃N₄ ball at high temperatures.

A Cr₃C₂–NiCr composite and a Cr₃C₂–NiCr–Mo–BaF₂ composite were prepared using spark plasma sintering. Tribological properties of the composites were investigated using a ball-on-disk type tribotester. The relationships among the microstructure, wear mechanism and tribological performance were determined by analyzing the wear track morphologies and the glaze layer’s phase composition.

The wear rate of the Cr₃C₂–NiCr–Mo–BaF₂ composite was approximately one order of magnitude lower than that of the Cr₃C₂–NiCr composite from 700°C to 900°C when sliding against a Si₃N₄ ball. The favorable tribological performance of the Cr₃C₂–NiCr–Mo–BaF₂ composite at high temperatures results from the synergistic lubrication of MoOx, BaF₂ and BaMoO₄.

This paper reports a new Cr₃C₂–NiCr matrix self-lubricating composite with better tribological properties than Cr₃C₂–NiCr composite at temperatures up to 900°C through Mo and BaF₂ addition.

Aligning employees' goals with organizational goals is an overarching objective of an organization to increase employees' outcomes and, ultimately, the firm's performance. Employees' perceived goal congruence is proposed to be an important mediator of the effect of high-performance work systems (HPWS) on organizational citizenship behaviors (OCB). In this paper, the authors proposed and tested a moderated mediation model that depicted how servant leadership increased or restrained these effects.

This study used data from 56 managers and 322 employees working in Bangladeshi organizations. The study conducted cross-level analyses using hierarchical linear modeling (HLM) to examine the hypothetical relationships among variables.

This study revealed that employees' perceived goal congruence mediated the influence of HPWS on OCB. Consistent with the moderated mediation prediction, employee-perceived goal congruence mediated the relationship between HPWS and OCB when servant leadership is high.

This study examined how and when HPWS affects OCB by incorporating perceived goal congruence and servant leadership as mediating and moderating variables, respectively.

To overcome the limitations of traditional multi-attribute decision making (MADM) methods, which only provide deterministic rankings of decision objects, this paper proposes a novel multi-attribute 3WD model. This model presents three-parameter interval grey number decision-theoretic rough sets (TPIGNDTRSs), aiming to offer a reasoned interpretation of loss functions in grey environments and ensure objective assessment of conditional probabilities.

Firstly, the traditional equivalence relation is replaced with the probabilistic dominance relation (PDR), categorizing decision objects into two state sets in DTRS for more objective conditional probabilities. Secondly, as the three-parameter interval grey number (TPIGN) introduces the most probable value on the basis of the traditional two-parameter interval grey number, it provides a more comprehensive method for describing grey information. Consequently, integrating TPIGN into DTRS refines the interpretations of loss functions in grey environments. Finally, by utilizing two main sorting techniques, relative kernel and degree of accuracy ranking and possibility ranking, two types of 3WD rules with TPIGNDTRSs, are constructed.

This study has successfully developed and validated a new multi-attribute 3WD model. The model was tested in two distinct domains: evaluating innovation efficiency in high-tech enterprises and recommending movies in a practical case. The findings reveal that the model can effectively integrate relevant information of high-tech enterprises, provide the government with enterprise-level assessments, and gather consumer preferences to recommend the most suitable movies.

This study treats the loss function as grey information in the 3WD model but overlooks the grey nature of evaluation values, limiting its applicability. Additionally, the model’s reliance on subjective expert judgments and historical data to establish the loss function may affect its objectivity. The implications of this research are that the novel model overcomes traditional MADM limitations, enhancing decision-making quality and efficiency in complex and grey scenarios. The model’s successful application in evaluating high-tech enterprises and recommending movies illustrates its dual value in both theory and practice.

Initially, the model proposed in this study is of significant importance for the development of the 3WD field, as it successfully addresses the challenges of uncertain loss functions and unknown conditional probabilities in grey information environments. Moreover, by integrating the 3WD model with MADM problems, it has broken through the bottlenecks of traditional MADM methods, offering new perspectives and strategies for solving MADM issues. Therefore, this research not only advances theoretical research but also provides powerful tools for practical applications.

The purpose of this study is to build a link between narcissistic supervision and employees' change-oriented organizational citizenship behaviors (OCBs). On the basis of the social dynamics of state paranoia theory, the study examines the relationship between narcissistic supervision and employees' change-oriented OCBs, and explores how this relationship is mediated by psychological safety and affective organizational commitment.

Using data collected from a sample of 183 employee–leader dyads from a technology company in China, the study examines the mediating effects of psychological safety and affective organizational commitment on the relationship between narcissistic supervision and employees' change-oriented OCBs. Structural equation modeling is used to analyze the data.

The results indicate that narcissistic supervision has a negative effect on psychological safety and affective organizational commitment; psychological safety mediates the relationship between narcissistic supervision and affective organizational commitment; and affective organizational commitment mediates the relationship between psychological safety and employees' change-oriented OCBs. The results also show that the negative effect of narcissistic supervision on employees' change-oriented OCBs is mediated by psychological safety and subsequently affective organizational commitment.

This study contributes to the literature by linking narcissistic supervision and employees' change-oriented OCBs and suggesting that psychological safety and affective organizational commitment are two critical mediators of this relationship. This study not only advances research on the “dark side” of narcissistic supervision, but also sheds light on the underlying mechanism of narcissistic supervision and employees' change-oriented OCBs from the psychological and emotional perspectives.

The purpose of this study is to investigate the phenomenon of knowledge transfer between employees and coworkers. That is, when and why employees engage in knowledge seeking or knowledge sabotage when confronted with coworkers with higher relative overqualification.

This study collected survey data from 315 employee-coworker pairs in East China at three-time points.

The results showed that when the cooperative goal interdependence between employee and coworker is high, the perception of coworker’s relative overqualification will cause benign envy of employees, which in turn promote employees to engage in knowledge seeking from coworker. However, when the competitive goal interdependence between employee and coworker is high, the perception of coworker’s relative overqualification will cause malicious envy of employees, which in turn promote employees to engage in knowledge sabotage toward coworker.

This research not only expands the theoretical perspective and outcomes of relative overqualification but also enriches the mechanism of knowledge seeking and knowledge sabotage. Meanwhile, this study also provides practical guidance for enterprises to reduce knowledge sabotage.