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To use distinct element simulation (PFC2D) to investigate the relationships between microparameters and macroproperties of the specimens that are modeled by bonded particles. To determine quantitative relationships between particle level parameters and mechanical properties of the specimens.

A combined theoretical and numerical approach is used to achieve the objectives. First, theoretical formulations are proposed for the relationships between microparameters and macroproperties. Then numerical simulations are conducted to quantify the relationships.

The Young's modulus is mainly determined by particle contact modulus and affected by particle stiffness ratio and slightly affected by particle size. The Poisson's ratio is mainly determined by particle stiffness ratio and slightly affected by particle size. The compressive strength can be scaled by either the bond shear strength or the bond normal strength depending on the ratio of the two quantities.

The quantitative relationships between microparameters and macroproperties for parallel‐bonded PFC2D specimens are empirical in nature. Some modifications may be needed to model a specific material. The effects of the particle distribution and bond strength distribution of a PFC2D specimen are very important aspects that deserve further investigation.

The results will provide guidance for people who use distinct element method, especially the PFC2D, to model brittle materials such as rocks and ceramics.

This paper offers some new quantitative relationships between microparameters and macroproperties of a synthetic specimen created using bonded particle model.

The purpose of this paper is to examine how team social media usage (SMU) affects two types of knowledge sharing (KS), namely, in-role and extra-role KS, and then individual job performance. The study also examines the mediating effects of two types of KS and the main and moderating effects of team performance norms on individual job performance.

This study applies the theory of communication visibility to develop a cross-level model and then validate it through a three-wave survey from 600 individuals in 120 teams. Hierarchical linear model is used to test the hypotheses.

The results suggest that team SMU improves team members’ in-role and extra-role KS, and thus enhances their individual job performance. The in-role and extra-role KS have partial mediating effects between team SMU and job performance. The results also show that team performance norms have a positive main effect on individual job performance, but negatively moderate the relationship between individual extra-role KS and job performance.

This study contributes to the operations management literature by examining the effects of team SMU from a multilevel perspective.

The findings provide managers with ways to improve individual KS and job performance.

This study is one of the first to investigate the effects of team SMU on individual KS and job performance. It also identifies the two-sided effects of team performance norms.

This paper aims to design a tip state estimation method for a hybrid-structured flexible manipulator (HSFM) with one rotating joint and one telescopic joint in the vertical plane.

The HSFM model is decomposed into a static deflection model and a vibration model. The sliding discrete Fourier transform (SDFT) is used to filter the high frequency noise and obtain main vibration components to represent the vibration model. Then, a novel fuzzy logic adaptive Kalman filter (FLAKF) is designed to estimate the state of a vibrational equilibrium position. The complete tip state of the HSFM is obtained by superimposing the FLAKF filter results with the SDFT vibration analysis results.

Both the simulation results and physical experimental results verify the effectiveness of the proposed tip state estimation method. The vibration analysis based on SDFT is used to represent the vibration model and reduce the computational complexity in the process of solving differential equation. The proposed FLAKF can effectively increase the stability and robustness of the estimator.

In this paper, the tip state estimation problem of the HSFM in vertical plane is first proposed. The effect of gravity on the HSFM is considered by the static deflection model. A precise tip state estimator is designed by a closed loop SDFT and a novel FLAKF, which can provide an accurate feedback for the vibration control controller and make an accurate evaluation of the control effect.

The purpose of this paper is to propose a variable impedance control method of finger exoskeleton for hand rehabilitation using the contact forces between the finger and the exoskeleton, making the output trajectory of finger exoskeleton comply with the natural flexion-extension (NFE) trajectory accurately and adaptively.

This paper presents a variable impedance control method based on fuzzy neural network (FNN). The impedance control system sets the contact forces and joint angles collected by sensors as input. Then it uses the offline-trained FNN system to acquire the impedance parameters in real time, thus realizing tracking the NFE trajectory. K-means clustering method is applied to construct FNN, which can obtain the number of fuzzy rules automatically.

The results of simulations and experiments both show that the finger exoskeleton has an accurate output trajectory and an adaptive performance on three subjects with different physiological parameters. The variable impedance control system can drive the finger exoskeleton to comply with the NFE trajectory accurately and adaptively using the continuously changing contact forces.

The finger is regarded as a part of the control system to get the contact forces between finger and exoskeleton, and the impedance parameters can be updated in real time to make the output trajectory comply with the NFE trajectory accurately and adaptively during the rehabilitation.

The torque ripple and fault-tolerant capability are the two main problems for the switched reluctance motors (SRMs) in applications. The purpose of this paper, therefore, is to propose a novel 16/10 segmented SRM (SSRM) to reduce the torque ripple and improve the fault-tolerant capability in this work.

The stator of the proposed SSRM is composed of exciting and auxiliary stator poles, while the rotor consists of a series of discrete segments. The fault-tolerant and torque ripple characteristics of the proposed SSRM are studied by the finite element analysis (FEA) method. Meanwhile, the characteristics of the SSRM are compared with those of a conventional SRM with 8/6 stator/rotor poles. Finally, FEA and experimental results are provided to validate the static and dynamic characteristics of the proposed SSRM.

It is found that the proposed novel 16/10 SSRM for the application in the belt-driven starter generator (BSG) possesses these functions: less mutual inductance and high fault-tolerant capability. It is also found that the proposed SSRM provides lower torque ripple and higher output torque. Finally, the experimental results validate that the proposed SSRM runs with lower torque ripple, better output torque and fault-tolerant characteristics, making it an ideal candidate for the BSG and similar systems.

This paper presents the analysis of torque ripple and fault-tolerant capability for a 16/10 segmented switched reluctance motor in hybrid electric vehicles. Using FEA simulation and building a test bench to verify the proposed SSRM’s superiority in both torque ripple and fault-tolerant capability.

This paper aims to examine the influence of collaborative culture on employee’s knowledge sharing and how it associated with radical and incremental innovation in Chinese firms.

This study used the quantitative approach and structure equation model to test hypotheses with data collected by questionnaire from 371 participants in 68 Chinese firms.

The research findings indicated that collaborative culture positively fosters the KS behaviors of employees for radical and incremental innovation. The findings confirm the mediating role of tacit and explicit knowledge sharing and reveal that collaborative culture has a significant impact on incremental innovation, whereas knowledge sharing behaviors have greater impacts on radical and incremental innovation.

Future research should investigate the impact of collaborative culture on innovation under moderating effects of ownership form or mediating roles of behavioral variables to have better understanding on the relationship among them.

This study offers leaders a deeper understanding of the necessary factors and new pathways to stimulate employees’ tacit and explicit knowledge sharing for innovation.

The paper has significant contributed to theoretical and practical initiatives on the theory of innovation which highlighted the crucial role of collaborative culture in facilitating a positive climate for knowledge sharing and innovation.

The purpose of this paper is to investigate the correlation between ethical leadership (EL), collaborative culture (CC), knowledge-centered culture and employees’ behaviors toward knowledge sharing (KS) in Chinese firms.

The paper used structural equation modeling to examine the level of how EL, CC and knowledge-centered culture impact on tacit and explicit KS of employees via the data collected from 319 participants in 51 Chinese firms.

The research findings show collaborative and knowledge-centered culture mediates the relationship between EL and employees’ KS behaviors. It highlights the necessity of practicing EL style to develop a positive climate aimed at positively improving tacit and explicit KS of employees.

Future studies should focus on investigating the relationship between EL, CC and knowledge management process or the other variables to explore and maximize their potential and benefits toward key organizational outcomes.

This paper offers leaders a deeper understanding of the effective pathways to build positive climates for fostering employees’ tacit and explicit KS.

This paper is unique in the attempts to increase the understanding of moral lens by which EL might successfully arouse a positive organizational culture and foster KS behaviors in their firms.

The purpose of this paper is to examine the effect of ethical leadership on radical and incremental innovation through the mediating roles of tacit and explicit knowledge sharing (KS).

The paper used a quantitative research method and structural equation modeling to test the research hypotheses based on a sample of 365 participants from 115 Vietnamese firms.

The results indicated that ethical leadership is positively related to radical and incremental innovation. In addition, tacit and explicit KS significantly mediate the relationship between ethical leadership and the two types of innovation.

This study is cross-sectional, which limits its ability to control the specific features of the correlations among the factors in the long term.

The findings of this study suggest that leaders should invest in practicing and applying a moral lens to motivate positive KS behaviors of employees and organizational capabilities for innovation.

This study significantly fills gaps in the literature and advances the understanding of how ethical leadership fosters employees’ KS to improve radical and incremental innovation.

Construction resources are often limited, and there is a need to ensure resources are carefully allocated to avoid resource wastage and/or project delay. While mathematical and heuristic models were developed to resolve the conflicts between activities, none of them has been proven to be totally satisfactory. The aim of this paper is to explore this.

In this paper, a novel heuristic method known as a pull‐driven approach (PDA) is proposed; and this approach encourages a lean consideration of resource supply and partnering between activities. Two case studies are presented to illustrate how PDA can be applied. A comparison with another heuristic approach, namely the ranked positional weight method is conducted to illustrate the efficiency of the proposed approach.

Using the PDA approach, all the activities strive to find matching partners to pull resources to their sides. The resources are, therefore, no longer passively pushed to a single activity with high ranking but a combination of activities that can demonstrate their superiority in resource utilisation will actively win the necessary resources.

This approach has an ability to deal with intermittent activities and locate the lean (no‐waste) supply level of each resource.

Knowledge sharing (KS) and innovation are generally believed as the antecedents of key outcomes that help firms to attain and sustain competitive advantage in long term. The purpose of this paper is to analyze the mechanism of how interpersonal trust and leader support affect KS and improve firm’s innovation capabilities.

This is a research paper which is built using empirical data collected from 68 manufacturing and service firms in China.

First, the findings show that leader supports moderate the correlation between interpersonal trust and KS. Second, KS serves as mediator in the relationship between interpersonal trust and firm’s innovation capabilities.

KS plays a crucial role in stimulating innovation capabilities for both manufacturing and service firms. Future research should explore the effects of the motivational factors (such as positive psychological state, perceived benefits and costs) on KS and firm’s innovation capabilities.

The paper provides the evidence for the positive effects of interpersonal trust on KS, which in turn is significantly associated with product innovation and process innovation. It highlights the important role of leader supports in promoting the degree of sharing knowledge among individuals to enhance innovation capabilities for firms.

This study puts the theory of innovation forward based on exploring the key factors that have potential and positive impacts on two specific types of innovation capability, namely, product innovation and process innovation, for both manufacturing and service firms.