Yongxin Zhou, Qian Li, Zhiguo Xing, Renze Zhou, Zhenhua Huang, Yanfei Huang and Weiling Guo
This paper aims to investigate the effect of aluminum addition on the microstructure and mechanical properties of Mg-8Gd-4Y-1Zn alloy.
Abstract
Purpose
This paper aims to investigate the effect of aluminum addition on the microstructure and mechanical properties of Mg-8Gd-4Y-1Zn alloy.
Design/methodology/approach
Mg-8Gd-4Y-1Zn-xAl (x = 0, 0.5, 1.0, 1.5, 2.0 Wt.%) alloys were prepared by the conventional gravity casting technology, and then microstructures, phase composition and mechanical properties were investigated by material characterization method, systematically.
Findings
Results show that the as-cast microstructure of Mg-8Gd-4Y-1Zn alloy mainly consists of a-Mg matrix as well as Mg12REZn (18 R LPSO structure), and island-like Mg3(RE, Zn) phase is distributed at the grain boundary. The addition of a small amount of Al (0.5 Wt.%) can decrease the content of island-like Mg3(RE, Zn) phase, but significantly increase the content of long-period stacking ordered (LPSO) structure, resulting in the improvement of both tensile strength and elongation of Mg-8Gd-4Y-1Zn alloy. However, the addition of excessive Al will consume Re element and decrease the amount of LPSO structure, leading to the decrease of tensile properties. When the content of Al is 0.5 Wt.%, the tensile strength and elongation are 225 MPa and 9.0% of Mg-8Gd-4Y-1Zn alloy, which are 14% and 29% higher than that of Mg-8Gd-4Y-1Zn alloy, respectively.
Originality/value
Adding aluminum to Mg-8Gd-4Y-1Zn alloy strengthens its mechanical properties. And the effect of Al content on the alloy strengthening. The formation mechanism of LPSO structure with different aluminum content was revealed.
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Renze Zhou, Zhiguo Xing, Haidou Wang, Zhongyu Piao, Yanfei Huang, Weiling Guo and Runbo Ma
With the development of deep learning-based analytical techniques, increased research has focused on fatigue data analysis methods based on deep learning, which are gaining in…
Abstract
Purpose
With the development of deep learning-based analytical techniques, increased research has focused on fatigue data analysis methods based on deep learning, which are gaining in popularity. However, the application of deep neural networks in the material science domain is mainly inhibited by data availability. In this paper, to overcome the difficulty of multifactor fatigue life prediction with small data sets,
Design/methodology/approach
A multiple neural network ensemble (MNNE) is used, and an MNNE with a general and flexible explicit function is developed to accurately quantify the complicated relationships hidden in multivariable data sets. Moreover, a variational autoencoder-based data generator is trained with small sample sets to expand the size of the training data set. A comparative study involving the proposed method and traditional models is performed. In addition, a filtering rule based on the R2 score is proposed and applied in the training process of the MNNE, and this approach has a beneficial effect on the prediction accuracy and generalization ability.
Findings
A comparative study involving the proposed method and traditional models is performed. The comparative experiment confirms that the use of hybrid data can improve the accuracy and generalization ability of the deep neural network and that the MNNE outperforms support vector machines, multilayer perceptron and deep neural network models based on the goodness of fit and robustness in the small sample case.
Practical implications
The experimental results imply that the proposed algorithm is a sophisticated and promising multivariate method for predicting the contact fatigue life of a coating when data availability is limited.
Originality/value
A data generated model based on variational autoencoder was used to make up lack of data. An MNNE method was proposed to apply in the small data case of fatigue life prediction.
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Chuqin Yuan, Yanfei Wang, Wenyuan Huang and Yu Zhu
The purpose of this paper is to explore the influencing mechanism of coaching leadership (CL) on employee voice behavior (VB) based on cognitive-affective system theory of…
Abstract
Purpose
The purpose of this paper is to explore the influencing mechanism of coaching leadership (CL) on employee voice behavior (VB) based on cognitive-affective system theory of personality (CAPS). Specifically, the study intends to build a model of psychological security (PS) and openness to change (OC) that mediate the relationship between CL and employee VB at an individual-level and group-level from cognitive-affective dual perspective.
Design/methodology/approach
CL, employee VB, PS and OC were assessed in an empirical study based on a supervisor–subordinate dyads sample of 287 employees and 72 team leaders from enterprises in Southern China.
Findings
From CAPS theory perspective, the authors found that CL promotes employee VB and that PS and OC mediate the relationship between CL and VB.
Practical implications
Results underscore the importance of encouraging managers to engage in CL behaviors, which are conductive to enhancing employee PS and OC thereby improving employee VB. These results also highlight the significance of managerial attention to a secure voice atmosphere and the improvement of employees’ affective commitment to organizational change.
Originality/value
The research findings provide a significant contribution to the literature in that it shows PS and OC as crucial dual mediating mechanism through which CL influences VB. Moreover, this paper is one of the few studies answering the call to examine the effect of leadership at multiple levels.
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Yanfei Lu, Futian Weng and Hongli Sun
This paper aims to introduce a novel algorithm to solve initial/boundary value problems of high-order ordinary differential equations (ODEs) and high-order system of ordinary…
Abstract
Purpose
This paper aims to introduce a novel algorithm to solve initial/boundary value problems of high-order ordinary differential equations (ODEs) and high-order system of ordinary differential equations (SODEs).
Design/methodology/approach
The proposed method is based on Hermite polynomials and extreme learning machine (ELM) algorithm. The Hermite polynomials are chosen as basis function of hidden neurons. The approximate solution and its derivatives are expressed by utilizing Hermite network. The model function is designed to automatically meet the initial or boundary conditions. The network parameters are obtained by solving a system of linear equations using the ELM algorithm.
Findings
To demonstrate the effectiveness of the proposed method, a variety of differential equations are selected and their numerical solutions are obtained by utilizing the Hermite extreme learning machine (H-ELM) algorithm. Experiments on the common and random data sets indicate that the H-ELM model achieves much higher accuracy, lower complexity but stronger generalization ability than existed methods. The proposed H-ELM algorithm could be a good tool to solve higher order linear ODEs and higher order linear SODEs.
Originality/value
The H-ELM algorithm is developed for solving higher order linear ODEs and higher order linear SODEs; this method has higher numerical accuracy and stronger superiority compared with other existing methods.
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Lixun Zheng, Yanfei Wang, Zisheng Guo and Yu Zhu
The purpose of this paper is to examine the impact of managerial coaching (MC) on employee creative performance (CP) based on the knowledge transfer theory and the roles of…
Abstract
Purpose
The purpose of this paper is to examine the impact of managerial coaching (MC) on employee creative performance (CP) based on the knowledge transfer theory and the roles of creative process engagement (CPE) and climate for innovation (IC) in the relationship between MC and CP.
Design/methodology/approach
A moderated mediation model was developed and tested on a dyadic sample of 74 leaders and 292 employees working in South China firms.
Findings
The results show that CPE mediates the relationship between MC and CP and IC amplifies the indirect relationship between MC and CP via CPE.
Originality/value
This research contributes to the MC and innovation literature by clarifying the linking role of engagement in transferring MC into employees' CP from a knowledge transfer perspective and identifies the critical role of IC in effectuating the impact of MC on CP.
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Jieqiong Liu, Yanfei Wang and Yu Zhu
This study proposes a moderated mediation model that examines the roles that openness to change and psychological capital (PsyCap) may play in the relationship between climate for…
Abstract
Purpose
This study proposes a moderated mediation model that examines the roles that openness to change and psychological capital (PsyCap) may play in the relationship between climate for innovation and employee creativity.
Design/methodology/approach
Path modeling analysis with software Mplus 7 is conducted to test our moderated mediation model.
Findings
The results show that climate for innovation promotes openness to change, which in turn encourages employee creativity, and PsyCap moderates not only the relationship between climate for innovation and openness to change but also the indirect effect of climate for innovation on employee creativity through openness to change.
Research limitations/implications
Although we attempt to avoid common method bias by collecting data in two waves, the six-month time interval separating the two waves of data collection may not be long enough to detect the causal relationship between climate for innovation and employee creativity. In addition, this study is conducted in companies located in China, which may raise the question of generalizability to other cultures.
Originality/value
The main contribution is building a moderated mediation model to uncover the potential mediating mechanism and boundary conditions associated with the influence of climate for innovation on employee creativity.
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Yanfei Wang, Jieqiong Liu and Yu Zhu
The purpose of this paper is to develop a moderated mediation model to examine the roles that psychological capital (PsyCap) and growth need strength may play in the relationship…
Abstract
Purpose
The purpose of this paper is to develop a moderated mediation model to examine the roles that psychological capital (PsyCap) and growth need strength may play in the relationship between humble leader behaviors and follower creativity.
Design/methodology/approach
Data were collected from a three-wave survey study with a sample of 165 matched leader-follower questionnaires in China. Multiple regression analyses, moderated regression analysis and bootstrapping analysis were used to test the hypotheses.
Findings
The results show that humble leader behaviors positively influence follower creativity, PsyCap mediates this influence and growth need strength not only moderates the relationship between humble leader behaviors and PsyCap, but also amplifies the indirect relationship between humble leader behaviors and follower creativity via PsyCap.
Research limitations/implications
Common method bias may still exit, although the measures of research variables were gathered from different sources and with time separation. Additionally, this study is conducted in a single cultural context, which may raise the question about the generalizability of our findings to other cultural contexts.
Originality/value
The primary contribution is building and examining a conceptual model that focuses on the potential effect of humble leader behaviors on follower creativity. Additionally, by confirming the mediating role of PsyCap, the research further uncovers why followers under humble leader behaviors are more likely to engage in creativity, and the moderating role of growth need strength found in this study also offers additional insight into that followers may differ in the degree to which they are receptive to leader effect.
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Yanfei Yang, Xiaobo Wang, Sen Mei, Xing Zhu, Shiqiang Chen, Peng Xiong, Zhihai Hu, Kun Xiong and Dong Song Yuan
The purpose of this paper is to investigate the tribological performance and mechanisms of BN/calcium borate nanocomposites (BCBNs) as additives in lubricating oil.
Abstract
Purpose
The purpose of this paper is to investigate the tribological performance and mechanisms of BN/calcium borate nanocomposites (BCBNs) as additives in lubricating oil.
Design/methodology/approach
BCBNs were prepared by heterogeneous deposition method. And the morphology and structure of samples were analysed by transmission electron microscopy, Fourier transform infrared spectra and X-ray powder diffraction pattern. The maximum non-seizure load (PB) of samples was tested using four-ball friction tester. The average friction coefficients and wear tracks were obtained. In addition, tribological mechanism was also investigated using optical microscope, energy dispersive spectroscopy and X-ray photoelectron spectroscope.
Findings
It was found that the nanocomposites present core-shell nanostructure with the thickness of shell around 12 nm and the diameter of particles 100-200 nm, and tribological tests indicate that the PB value of BCBNs was increased by 113 per cent, whereas the average friction coefficient was decreased by 23.6 per cent and the bloom’s wear area was also decreased by 25.2 per cent.
Originality/value
This paper involves investigation on tribological properties and mechanism of the BCBNs with core-shell structure.
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Taegoo Terry Kim, Gyehee Lee, Soyon Paek and Seunggil Lee
The purpose of this paper is to investigate an integrative model that explores the influence of knowledge-sharing enablers (social capital (SC), including structural, relational…
Abstract
Purpose
The purpose of this paper is to investigate an integrative model that explores the influence of knowledge-sharing enablers (social capital (SC), including structural, relational, and cognitive SC) on knowledge-sharing (KS) processes (KS behaviors: knowledge collecting (KC) and knowledge donating (KD)) as well as a further superior KS outcome (organizational performance).
Design/methodology/approach
The survey was administered in 14 top tier five-star hotels in Seoul, Korea. Employees of the hotels participated in the survey; 486 surveys were used to investigate a research model and hypotheses using a path analysis.
Findings
The research confirmed the importance of SC in the context of KS from the resource-based view. The paper provides empirical evidence that structural, relational, and cognitive SC affected KC and KD, which in turn influenced organizational performance. Interestingly, whereas cognitive SC has the strongest effect on employees' KC, relational SC has the strongest effect on employees' KD. The impact of employees' KC on organizational performance appears to be stronger than that of KD.
Practical implications
The relationships among KS enablers, processes, and organizational performance may provide a clue regarding how hotels can promote KS culture, which focuses on the social dynamics derived from interpersonal and group relationships to boost their performance by increasing employees' willingness to collect knowledge from and donate knowledge to colleagues.
Originality/value
This study explores the under-researched subject of SC with regard to KS and their roles in promoting organizational performance within a hospitality industry context. The study is among the first to examine SC as an organizational resource, two distinctive types of KS behaviors as an organizational capability, and organizational performance from both an integrative (KS enablers-processes-outcomes framework) and resource-based view of the firm's perspective simultaneously. Especially, this study identifies the specific mechanism of two distinctive types of employees' KS behaviors, such as KC and KD, between SC factors and organizational performance.
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The purpose of this paper is to empirically explore intellectual capital (IC) from a multidimensional perspective and its relationship with organizational performance (OP) within…
Abstract
Purpose
The purpose of this paper is to empirically explore intellectual capital (IC) from a multidimensional perspective and its relationship with organizational performance (OP) within Iranian public listed companies.
Design/methodology/approach
Survey data from Chief Financial Officers in 128 companies within Tehran Stock Exchange were collected and analyzed using partial least squares regressions.
Findings
The findings suggest that organizational culture plays a significant role in developing human capital and structural capital while trust is a major determinant of all the IC components, namely human, structural, relational, and social capital. The results also confirm that the investment in human, structural, and relational capital could potentially bring about OP improvement in Iranian public listed companies.
Practical implications
A synthesis of various sub-elements of IC supports executives in detecting, capturing, and assessing the different kinds of knowledge resources which must be taken into consideration individually for maximizing OP. Such multidimensional and comprehensive conceptualization of IC would assist organizations to remedy the inefficiency in the exploitation of IC and thereby providing a robust system in order to capture and measure IC more effectively.
Originality/value
This study combines literature on IC across diverse academic fields. The multidimensional conceptualization of IC with four sub-dimensions (i.e. human, structural, relational, and social capital) as well as supplementing two antecedent constructs (trust and organizational culture) offer a more systematic manner to synthesize several knowledge-based drivers toward performance which have not been addressed simultaneously in a comprehensive framework.