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Article
Publication date: 30 September 2022

Gang Wang, Chenhui Xia, Bo Wang, Xinran Zhao, Yang Li and Ning Yang

A W-band antennas-in-packages (AIP) module with a hybrid stacked glass-compound wafer level fan-out process was presented. Heterogeneous radio frequency (RF) chips were…

Abstract

Purpose

A W-band antennas-in-packages (AIP) module with a hybrid stacked glass-compound wafer level fan-out process was presented. Heterogeneous radio frequency (RF) chips were integrated into one single module with a microscale fan-out process. This paper aims to find a new strategy for 5G communication with 3D integration of multi-function chips.

Design/methodology/approach

The AIP module was composed of two stacked layers: the antenna layer and RF layer. After architecture design and performance simulation, the module was fabricated, The 8 × 8 antenna array was lithography patterned on the 12 inch glass wafer to reduce the parasitic parameters effect, and the signal feeding interface was fabricated on the backside of the glass substrate.

Findings

AIP module demonstrates a size of 180 mm × 180mm × 1mm, and its function covers the complete RF front-end chain from the antenna to signal to process and can be applied in 5 G communication and automotive components.

Originality/value

With three RF multi-function chips and two through silicon via (TSV) chips were embedded in the 12 inch compound wafer through the fan-out packaging process; two layers were interconnected with TSV and re-distributed layers.

Details

Microelectronics International, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 29 September 2021

Gang Wang, Wei Wang, Yi Zhang, Xu Zhang, Zhaowen Hu, Kun Liu and Daogao Wei

This paper aims to investigate the micro-plastic behavior of granular material in three-body friction interface and its effect on friction characteristics.

Abstract

Purpose

This paper aims to investigate the micro-plastic behavior of granular material in three-body friction interface and its effect on friction characteristics.

Design/methodology/approach

A numerical model of particle breakage in friction contact was constructed based on the discrete element method. The influence of friction pair working condition and internal bonding strength on the micro-plastic behavior of particulate matter was analyzed. A reciprocating linear tribometer was used to verify the simulation results.

Findings

The results show that when the granular materials are squeezed and sheared by the friction pair, a shear zone inclined to the left is gradually formed, which leads to particle breakage. The breakage of the particle leads to the reduction of load-bearing capacity and the increase of friction coefficient. Due to the differences in bond strength and friction pairs working conditions, the particle plastic behavior is divided into the following three states: elastic deformation, breakage and plastic rheology.

Originality/value

This study is helpful to understand the effect of the micro-plastic behavior of particles on the three-body friction characteristics.

Details

Industrial Lubrication and Tribology, vol. 73 no. 8
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 28 April 2022

Gang Wang, Zihan Wang, Yue Zhang, GuangTao Xu, MingHao Zhao and Yanmin Li

The purpose of this paper is to find a new method to evaluate the hydrogen embrittlement performance of heterogeneous materials and thin film materials.

Abstract

Purpose

The purpose of this paper is to find a new method to evaluate the hydrogen embrittlement performance of heterogeneous materials and thin film materials.

Design/methodology/approach

The changes of hydrogen embrittlement properties of steel were studied by electrochemical hydrogen charging test and scratch test. The microstructure and properties of the alloy were analyzed by hardness tester, scanning electron microscope and three-dimensional morphology. The fracture toughness before and after hydrogen charging was calculated based on the scratch method.

Findings

The results showed that the hydrogen-induced hardening phenomenon occurs in the material after hydrogen charging. The scratch depth and width increased after hydrogen charging. The fracture toughness obtained by the scratch method showed that hydrogen reduces the fracture toughness of the material. The comparison error of fracture toughness calculated by indentation method was less than 5%.

Originality/value

The results show that the scratch method can evaluate the hydrogen embrittlement performance of the material. This method provides a possibility to evaluate the hydrogen embrittlement of thin-film and heterogeneous materials.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Open Access
Article
Publication date: 25 October 2021

Cong Li, YunFeng Xie, Gang Wang, XianFeng Zeng and Hui Jing

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

452

Abstract

Purpose

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Design/methodology/approach

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

Findings

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

Originality/value

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.

Details

Journal of Intelligent and Connected Vehicles, vol. 4 no. 3
Type: Research Article
ISSN: 2399-9802

Keywords

Article
Publication date: 11 October 2021

Dayong Zhang, Xiaohui Liu, Xuefeng Bai, Gang Wang, Liping Rong, Ying Zhao, Xin Li, Jinhua Zhu and Changhong Mi

The purpose of this study is to investigate the heat resistance and heat-resistant oxygen aging of 4-nitrophthalonitrile-etherified cardanol-phenol-formaldehyde (PPCF) to…

Abstract

Purpose

The purpose of this study is to investigate the heat resistance and heat-resistant oxygen aging of 4-nitrophthalonitrile-etherified cardanol-phenol-formaldehyde (PPCF) to further use and develop the resin as the matrix resin of high-temperature resistant adhesives and coatings.

Design/methodology/approach

PPCF resin was synthesized by 4-nitrophthalonitrile and cardanol-phenol-formaldehyde (PCF). The structures of PPCF and PCF were investigated by Fourier transform infrared, differential scanning calorimetry and proton nuclear magnetic resonance. In addition, the heat resistance and processability of PPCF and PCF resins were studied by dynamic mechanical analysis, thermogravimetric analysis, scanning electronic microscopy (SEM), X-ray diffraction (XRD) techniques and rheological studies.

Findings

The results reveal that PPCF forms a cross-linked network at a lower temperature. PPCF resin has excellent resistance under thermal aging in an air atmosphere and that it still had a certain residual weight after aging at 500°C for 2 h, whereas the PCF resin is completely decomposed.

Originality/value

4-Nitrophthalonitrile was introduced into PCF resin, and XRD and SEM were used to investigate the high temperature residual carbon rate and heat-resistant oxygen aging properties of PPCF and PCF resins.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 16 November 2018

Soheil Mohajerani, Duruo Huang, Gang Wang, Seyed-Mohammad Esmaeil Jalali and Seyed Rahman Torabi

This study aims to develop an efficient algorithm for generation of conforming mesh for seepage analysis through 3D discrete fracture networks (DFN).

110

Abstract

Purpose

This study aims to develop an efficient algorithm for generation of conforming mesh for seepage analysis through 3D discrete fracture networks (DFN).

Design/methodology/approach

The algorithm is developed based on a refined conforming Delaunay triangulation scheme, which is then validated using analytical solutions. The algorithm is well able to meet the challenge of meshing complex geometry of DFNs.

Findings

A series of sensitivity analysis have been performed to evaluate the effect of meshing parameters on steady state solution of Darcy flow using a finite element scheme. The results show that an optimized minimum internal angle of meshing elements should be predetermined to guarantee termination of the algorithm.

Originality/value

The developed algorithm is computationally efficient, fast and is of low cost. Furthermore, it never changes the geometrical structure and connectivity pattern of the DFN.

Details

Engineering Computations, vol. 35 no. 8
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 8 August 2018

Gang Wang, Xiaohui Liu, Changhong Mi, Huijuan Fan, Bo Xu and Xuefeng Bai

The purpose of this study was to investigate the microstructural evolution and hydrolytic stability of poly(phenylborosiloxane) (PPhBS) to further use and develop the…

Abstract

Purpose

The purpose of this study was to investigate the microstructural evolution and hydrolytic stability of poly(phenylborosiloxane) (PPhBS) to further use and develop the oligomers as heat-resistant modifiers.

Design/methodology/approach

PPhBS was synthesized by direct co-condensation of boric acid (BA) and phenyltriethoxysilane (PTEOS). The structural evolution of PPhBS at high temperature was investigated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), differential thermal analysis (DTA), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and 29Si nuclear magnetic resonance (NMR) spectroscopy. In addition, the change in the morphology of the PPhBS powder was examined to demonstrate the evolution of the chemical bonds, and the hydrolytic stability of PPhBS was investigated by a combination of X-ray diffraction (XRD) analysis, measurement of the mass loss in water and FTIR spectroscopy.

Findings

The results revealed that a cross-linking network was gradually formed with increasing temperature through the condensation of the residual hydroxyl groups in PPhBS, and the Si-OH and B-OH bonds remained even at a high temperature of 450°C. Furthermore, heat treatment improved the hydrolytic stability of the oligomer. The hydrolysis of the B-O-B bonds in PPhBS was reversible, whereas the Si-O-Si and Si-O-B bonds were highly resistant to hydrolysis.

Practical implications

The prepared PPhBS can be used as a heat-resistant modifier in adhesives, sealants, coatings and composite matrices.

Originality/value

Investigation of the structural evolution of a polyborosiloxane at high temperature by DRIFTS is a novel approach that avoided interference from moisture in the air. The insoluble mass fraction and the FTIR spectrum of PPhBS washed with water were used to investigate the hydrolytic stability of PPhBS.

Details

Pigment & Resin Technology, vol. 47 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 12 March 2018

Jibao Gu, Gang Wang, Hefu Liu, Derun Song and Changqing He

The present study aims to examine how and when authoritarian leadership affects employee creativity. Based on social exchange theory and team identification literature…

2411

Abstract

Purpose

The present study aims to examine how and when authoritarian leadership affects employee creativity. Based on social exchange theory and team identification literature, the present research attempts to simultaneously explore how leader–member exchange (LMX) and team identification serve as two important mediating processes in the relationship between authoritarian leadership and employee creativity. Furthermore, this research uncovers the mechanism under which conditions the effects of authoritarian leadership will be magnified or minimized.

Design/methodology/approach

A survey has been conducted in China by using a questionnaire to collect data. The study sample consisted of 325 employees. LISREL 8.7 and SPSS 18.0 were used to test the mediating and moderating effects, respectively.

Findings

Results from 325 employees revealed that both LMX and team identification mediated the negative relationships between authoritarian leadership and employee creativity. Specifically, the relationship between two mediators was that LMX was positively related to team identification. In addition, the relationship between authoritarian leaderships and LMX and team identification was moderated by power distance, such that the negative relationships will be weaker with high power distance and stronger with low power distance.

Practical implications

First, firms and managers should recognize and take actions to reduce the negative effects of authoritarian leadership, such as effective selection system and interventional mechanisms because authoritarian leadership is important in influencing employee creativity. Second, managers are suggested to take specific actions, such as increasing communications and team-building activities, to promote LMX and team identification, thereby enhancing employee creativity. Third, managers should engage in behaviors that motivate employee creativity, such as empowerment behaviors, other than authoritarian leadership, when the employee has low power distance.

Originality/value

The primary contribution of this research is that two psychological processes (i.e. LMX and team identification) have been identified through which authoritarian leadership is related to employee creativity. Meanwhile, this study explores the relationship between LMX and team identification. Moreover, the current research deepens our understanding of power distance by empirically examining the moderating effect of power distance. Overall, the findings extend our understanding about the relationship between authoritarian leadership and employee creativity and contribute to literature on authoritarian leadership and creativity.

Details

Chinese Management Studies, vol. 12 no. 2
Type: Research Article
ISSN: 1750-614X

Keywords

Article
Publication date: 30 April 2020

Gang Wang, Yue Zhang, Chen Gao, GuangTao Xu and MingHao Zhao

The purpose of this paper is to investigate, the effects of residual stress and microstructure on the corrosion behaviour of carburised 18CrNiMo7-6 steel in a 3.5% NaCl…

Abstract

Purpose

The purpose of this paper is to investigate, the effects of residual stress and microstructure on the corrosion behaviour of carburised 18CrNiMo7-6 steel in a 3.5% NaCl aqueous solution.

Design/methodology/approach

The electrochemical tests were conducted using an electrochemical workstation with a three-electrode system in a 3.5% NaCl aqueous solution, the residual stress of each working face was measured by a high-speed residual stress analyser, and microstructure of different carburised layers were observed scanning electron microscopy. Finally, the effect of carbon content, microstructure and residual stress on the corrosion behaviour of the steel was discussed.

Findings

The results showed that the residual compressive stress in the carburised layer initially increased and subsequently decreased with increasing depth of the carburised layer, reaching stability in the matrix layer. The electrochemical tests before and after stress reduction showed that the electrochemical impedance and the electrochemical potential increased with the reduction of residual compressive stress.

Originality/value

The residual compressive stress in the carburised layer initially increases and subsequently decreases with increasing carburised layer depth. The electrochemical impedance and the electrochemical potential increased with the reduction of residual compressive stress. The general relationship between electrochemical potential and residual stress was established.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 13 April 2020

Joshua C. Palmer, Yunhyung Chung, Youngkyun Park and Gang Wang

Drawing on broaden-and-build theory and promotion- and prevention-focus theory, the authors examined the role of positive and negative affectivity (PANA) on the riskiness…

Abstract

Purpose

Drawing on broaden-and-build theory and promotion- and prevention-focus theory, the authors examined the role of positive and negative affectivity (PANA) on the riskiness of investment decisions. The authors also examined the mediating impact of financial knowledge network intensity (i.e. the level of communication with financially literate others in employees' social network) on the PANA—riskiness of investment decisions relationship.

Design/methodology/approach

Study 1 used a sample of undergraduate students and operationalized risk using a hypothetical investment scenario. Study 2 replicated and extended the Study 1 findings using employees and operationalized risk using their real-world investment allocations.

Findings

Both Studies 1 and 2 provided support for the negative direct relationship between NA and the riskiness of investment decisions. Study 2 found PA was marginally positively related to the riskiness of investment decisions. Financial knowledge network intensity mediated the relationship between NA and the riskiness of investment decisions in Study 2.

Research limitations/implications

The findings suggest that employees who see the world in a generally negative light tended to have weaker financial knowledge networks, and this may be one mechanism that explains why they make low-risk investments.

Practical implications

Financial knowledge networks can provide access to critical information regarding investment opportunities. Socialization training or social mixers can be used to help employees build and improve their financial knowledge networks.

Originality/value

The authors integrate the research on PANA, social networks, and investment decisions to illuminate the social network processes that explain how affectivity impacts the riskiness of retirement investment decisions.

Details

Personnel Review, vol. 49 no. 9
Type: Research Article
ISSN: 0048-3486

Keywords

1 – 10 of 761