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Based on the social information processing theory, the purpose of this study is to propose a conceptualized moderated mediation model for testing the linkage between leader narcissism and employees’ innovative behavior through the mediating effect of employees’ cognitive dependency and the moderating effect of environmental uncertainty between employees’ cognitive dependency and their innovative behavior.

In this study, multisource data from 266 employees and their supervisors in 11 large high-tech Chinese companies were collected through a field study and an online survey. The hypotheses were tested using structural equation modeling and bootstrapping.

The results of this study show that leader narcissism has a negative impact on employees’ innovative behavior and that employees’ cognitive dependency plays a mediating role between leader narcissism and employees’ innovative behavior. Cognitive dependency and environmental uncertainty play moderated mediation roles between leader narcissism and employees’ innovative behavior.

In the future, longitudinal research and experimental methods can be used to avoid common method bias. Further studies could allow leaders to evaluate environmental uncertainty and explore the emotional path by which leader narcissism has negative effects on followers’ innovation from social information processing theory. In addition, future studies can explore cognitive dependency more deeply from the perspectives of forced obedience and active worship.

Organizations should warn leaders to control the dark side of narcissism and minimize environmental uncertainty to reduce barriers to innovation.

This study constructs the path of the effect of leader narcissism on employees’ innovation through employees’ cognitive dependency in a specific context, which enriches theoretical research on the link between leaders’ traits and employees’ innovative behavior. Along with the finding of leader narcissism’s negative effect on employees’ innovative behavior, this study explores the dark side of leader narcissism in the context of China’s high-tech firms and environmental uncertainty.

Based on the intrinsic motivation theory and spiritual leadership theory, the current study proposes a chain mediation model for testing the linkage between spiritual leadership and employees' innovative behavior through individual values and role identity.

In this study, 309 valid leader–subordinate matching questionnaires from 10 Internet enterprises and 21 manufacturing enterprises in China were collected through a field study. The hypotheses were tested using structural equation modeling and bootstrapping.

The results show that spiritual leadership has a positive impact on employees' innovative behavior. Uncertainty avoidance and creative role identity not only respectively play a mediating role but also play a chain mediating role in the process of spiritual leadership influencing employees' innovative behavior.

This study explores the influence of leadership style on employees' individual values, which has rarely been done in previous studies. Furthermore, the research explores the impact of personal values (uncertainty avoidance) on employee self-perception (creative role identity). And it enriches the relationship between spiritual leadership and employees' innovative behavior and reveals the deeper influence mechanism between them.

This paper aims to propose a calibration model for kinematic parameters identification of serial robot to improve its positioning accuracy, which only requires position measurement of the end-effector.

The proposed model is established based on local frame representation of the product of exponentials (local POE) formula, which integrates all kinematic errors into the twist coordinates errors; then they are identified with the tool frame’ position deviations simultaneously by an iterative least squares algorithm.

To verify the effectiveness of the proposed method, extensive simulations and calibration experiments have been conducted on a 4DOF SCARA robot and a 5DOF drilling machine, respectively. The results indicate that the proposed model outperforms the existing model in convergence, accuracy, robustness and efficiency; fewer measurements are needed to gain an acceptable identification result.

This calibration method has been applied to a variable-radius circumferential drilling machine. The machine’s positioning accuracy can be significantly improved from 11.153 initially to 0.301 mm, which is well in the tolerance (±0.5 mm) for fastener hole drilling in aircraft assembly.

An accurate and efficient kinematic calibration model has been proposed, which satisfies the completeness, continuity and minimality requirements. Due to generality, this model can be widely used for serial robot kinematic calibration with any combination of revolute and prismatic joints.

Lapping is a vital flattening process to improve the quality of processed semiconductor wafers such as single-crystal sapphire wafers. This study aims to optimise the lapping process of the fixed-abrasive lapping plate of sapphire wafers with good overall performance [i.e. high material removal rate (MRR), small surface roughness (Ra) of the wafers after lapping and small lapping plate wear ratio (η)].

The influence of process parameters such as lapping time, abrasive size, abrasive concentration, lapping pressure and lapping speed on MRR, Ra and η of lapping-processed sapphire wafers was studied, and the results were combined with experimental data to establish a regression model. The multi-evaluation index optimisation problem was transformed into a single-index optimisation problem via an entropy method and the grey relational analysis (GRA) to comprehensively evaluate the performance of each parameter.

The results revealed that lapping time, abrasive size, abrasive concentration, lapping pressure and lapping speed had different influence degrees on MRR, Ra and η. Among these parameters, lapping time, lapping speed and abrasive size had the most significant effects on MRR, Ra and η, and the established regression equations predicted the response values of MRR, Ra and η to be 99.56%, 99.51% and 93.88% and the relative errors between the predicted and actual measured values were <12%, respectively. With increased lapping time, MRR, Ra and η gradually decreased. With increased abrasive size, MRR increased nearly linearly, whereas Ra and η initially decreased but subsequently increased. With an increase in abrasive concentration, MRR, Ra and η initially increased but subsequently decreased. With increased lapping pressure, MRR and η increased nearly linearly and continuously, whereas Ra decreased nearly linearly and continuously. With increased lapping speed, Ra initially decreased sharply but subsequently increased gradually, whereas η initially increased sharply but subsequently decreased gradually; however, the change in MRR was not significant. Comparing the optimised results obtained via the analysis of influence law, the parameters optimised via the entropy method and GRA were used to obtain sapphire wafers lapping with an MRR of 4.26 µm/min, Ra of 0.141 µm and η of 25.08, and the lapping effect was significantly improved.

Therefore, GRA can provide new ideas for ultra-precision processing and process optimisation of semiconductor materials such as sapphire wafers.