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Article
Publication date: 28 February 2022

Yexin Zhou, Siwei Chen, Tianyu Wang and Qi Cui

This study analyzes the causal effect of education on consumers' cognition and attitudes toward genetically modified (GM) foods.

Abstract

Purpose

This study analyzes the causal effect of education on consumers' cognition and attitudes toward genetically modified (GM) foods.

Design/methodology/approach

The authors propose an analytical framework to clarify the role of education levels and education content in the formation of attitudes toward GM foods and utilize education reforms in China as natural experiments to test the theoretical predictions empirically. For education levels, the authors use Compulsory Education Law's implementation to construct the instrument variable. For education content, the authors utilize the revision of the biology textbook in the Eighth Curriculum Reform to implement staggered difference-in-difference estimation. The authors use two national household surveys, the China Genuine Progress indicator Survey (CGPiS) and the China Household Finance Survey (CHFS) of 2017, combined with provincial-level data of education reforms.

Findings

The education level, instrumented by the Compulsory Education Law's implementation, has an insignificant effect on consumers' cognition and attitudes toward GM foods, whereas the acquisition of formal education on genetic science, introduced by the Eighth Curriculum Reform, has a statistically significant and positive influence.

Originality/value

This is the first study to investigate the causal effects of education level and content on consumers' cognition and attitude toward GM foods using national representative data. It is also the first to evaluate the long-term effects of the biology textbook reform in China. The findings help open the black box of how education shapes people's preferences and attitudes and highlight the significance of formal biology education in formulating consumers' willingness to accept GM foods.

Details

China Agricultural Economic Review, vol. 14 no. 3
Type: Research Article
ISSN: 1756-137X

Keywords

Article
Publication date: 23 July 2021

Bao Qin, Yexin Zhou and Zheng Zhong

A diffusion-reaction-deformation coupled model is employed and implemented as a user-defined element (UEL) subroutine in the commercial finite element software package ABAQUS.

Abstract

Purpose

A diffusion-reaction-deformation coupled model is employed and implemented as a user-defined element (UEL) subroutine in the commercial finite element software package ABAQUS.

Design/methodology/approach

Chemical reaction and diffusion are treated as two distinct processes by introducing the extent of reaction and the diffusion concentration as two kinds of independent variables, for which the independent governing equations for chemical reaction and diffusion processes are obtained. Furthermore, an exponential form of chemical kinetics, instead of the linearly phenomenological relation, between the reaction rate and the chemical affinity is used to describe reaction process. As a result, complex chemical reaction can be simulated, no matter it is around or away from equilibrium.

Findings

Two numerical examples are presented, one for validation of the model and another for the modeling of the deflection of a plane caused by a chemical reaction.

Originality/value

1. Independent governing equations for diffusion and reaction processes are given. 2. An exponential relation between the reaction rate and its driving force is employed. 3. The UEL subroutine is used to implement the finite element procedure.

Details

Engineering Computations, vol. 39 no. 3
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 11 June 2019

Qing Xie, Yucai Hu, Yexin Zhou and Wanshui Han

Poor bending response is a major shortcoming of lower-order elements due to excessive representation of shear stress/strain field. Advanced finite element (FE) formulations for…

Abstract

Purpose

Poor bending response is a major shortcoming of lower-order elements due to excessive representation of shear stress/strain field. Advanced finite element (FE) formulations for classical elasticity enhance the bending response by either nullifying or filtering some of the symmetric shear stress/strain modes. Nevertheless, the stress/strain field in Cosserat elasticity is asymmetric; consequently any attempt to nullify or filter the anti-symmetric shear stress/strain modes may lead to failure in the constant couple-stress patch test where the anti-symmetric shear stress/strain field is linear. This paper aims at enhancing the bending response of lower-order elements for Cosserat elasticity problems.

Design/methodology/approach

A four-node quadrilateral and an eight-node hexahedron are formulated by hybrid-stress approach. The symmetric stress is assumed as those of Pian and Sumihara and Pian and Tong. The anti-symmetric stress components are first assumed to be completely linear in order to pass the constant couple-stress patch test. The linear modes are then constrained with respect to the prescribed body-couple via the equilibrium conditions.

Findings

Numerical tests show that the hybrid elements can strictly pass the constant couple-stress patch test and are markedly more accurate than the conventional elements as well as the incompatible elements for bending problems in Cosserat elasticity.

Originality/value

This paper proposes a hybrid FE formulation to improve the bending response of four-node quadrilateral and eight-node hexahedral elements for Cosserat elasticity problems without compromising the constant couple-stress patch test.

Details

Engineering Computations, vol. 36 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 9 August 2023

Ziyan Guo, Xuhao Liu, Zehua Pan, Yexin Zhou, Zheng Zhong and Zilin Yan

In recent years, the convolutional neural network (CNN) based deep learning approach has succeeded in data-mining the relationship between microstructures and macroscopic…

Abstract

Purpose

In recent years, the convolutional neural network (CNN) based deep learning approach has succeeded in data-mining the relationship between microstructures and macroscopic properties of materials. However, such CNN models usually rely heavily on a large set of labeled images to ensure the accuracy and generalization ability of the predictive models. Unfortunately, in many fields, acquiring image data is expensive and inconvenient. This study aims to propose a data augmentation technique to enhance the performance of the CNN models for linking microstructural images to the macroscopic properties of composites.

Design/methodology/approach

Microstructures of composites are synthesized using discrete element simulations and Potts kinetic Monte Carlo simulations. Macroscopic properties such as the elastic modulus, Poisson's ratio, shear modulus, coefficient of thermal expansion, and triple-phase boundary length density are extracted on representative volume elements. The CNN model is trained using the 3D microstructural images as inputs and corresponding macroscopic properties as the labels. The comparison of the predictive performance of the CNN models with and without data augmentation treatment are compared.

Findings

The comparison between the prediction performance of CNN models with and without data augmentation showed that the former reduced the weighted mean absolute percentage error (WMAPE) for the prediction from 5.1627% to 1.7014%. This significant reduction signifies that the proposed data augmentation method can effectively enhance the generalization ability and robustness of CNN models.

Originality/value

This study demonstrates that data augmentation is beneficial for solving the problems of model overfitting, data scarcity, and sample imbalance for CNN-based deep learning tasks at a low cost. By developing more and advanced data augmentation techniques, deep learning accelerated homogenization will boost the multi-scale computational mechanics and materials.

Details

Engineering Computations, vol. 40 no. 7/8
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 9 May 2018

Weiwei Wu, Yexin Liu, Yanggi Kim and Pengbin Gao

This study aims to offer insights regarding the impact of emotional conflict on innovation behavior. This study also explores the boundary conditions by examining the moderating…

1551

Abstract

Purpose

This study aims to offer insights regarding the impact of emotional conflict on innovation behavior. This study also explores the boundary conditions by examining the moderating effects of leader-member exchange (LMX) and team-member exchange (TMX) on the relationship between emotional conflict and innovation behavior.

Design/methodology/approach

This study used a questionnaire survey to collect data in China. Hypotheses were tested using hierarchical regression analysis. To test for inverted U-shaped relationship between emotional conflict and innovation behavior, the authors computed the squared term for emotional conflict. To investigate moderating roles of LMX and TMX, the authors carried out an interaction term between the main effect variables (emotional conflict and emotional conflict2) and the moderating variables (LMX and TMX).

Findings

The empirical findings indicated that emotional conflict had an inverted U-shaped relationship with innovation behavior. Furthermore, LMX and TMX moderated the inverted U-shaped relationship between the emotional conflict and innovation behavior in such a way that the inverted U-shaped relationship was flatter in high-quality LMX and TMX than in low-quality LMX and TMX. That is to say, LMX and TMX may dampen the positive effects of lower levels of emotional conflict on innovation behavior; yet, it may also weaken the negative effects of higher levels of emotional conflict on innovation behavior.

Research limitations/implications

This research can be extended in several ways. First, future research can investigate the impact mechanism of emotional conflict on innovation behavior. Second, future research can analyze other types of moderators at different levels. The last but not the least, future research can test the results using heterogeneous samples. Despite these potential limitations, this study provides an elaborate understanding of the conflict–creativity relationship by outlining the inverted U-shaped relationship between emotional conflict and innovation behavior under the LMX and TMX contexts, which can make important contributions to the conflict management literature.

Practical implications

The findings of this study offer some guidance on how to stimulate innovation behavior through emotional conflict. It suggests that managers should maintain the emotional conflict at the moderate level. Furthermore, managers can strengthen the LMX and TMX to avoid the negative effects of high levels of emotional conflict, and several practices are provided as well.

Originality/value

This study develops an exhaustive understanding of the conflict–creativity relationship by figuring the curvilinear relationship between emotional conflict and innovation behavior, which is the response to the call of Posthuma to focus on the outcomes of conflict management. The findings further provide an empirical evidence of the conceptual argument that the consequences of conflict depend on the situational context by pointing out the important contingency factors of LMX and TMX.

Details

International Journal of Conflict Management, vol. 29 no. 3
Type: Research Article
ISSN: 1044-4068

Keywords

Expert briefing
Publication date: 11 December 2015

Elite politics in China.

Details

DOI: 10.1108/OXAN-DB207271

ISSN: 2633-304X

Keywords

Geographic
Topical
Article
Publication date: 20 December 2021

Xiang Qiu, Kun Zhang, Qin Kang, Yicheng Fan, Hongyu San, Yiqing Chen and Heming Zhao

This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement…

131

Abstract

Purpose

This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.

Design/methodology/approach

The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.

Findings

The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.

Originality/value

This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 29 July 2014

Xin Ye, Jun Gao, Zhijing Zhang, Chao Shao and Guangyuan Shao

The purpose of this paper is to propose a sub-pixel calibration method for a microassembly system with coaxial alignment function (MSCA) because traditional sub-pixel calibration…

Abstract

Purpose

The purpose of this paper is to propose a sub-pixel calibration method for a microassembly system with coaxial alignment function (MSCA) because traditional sub-pixel calibration approaches cannot be used in this system.

Design/methodology/approach

The in-house microassembly system comprises a six degrees of freedom (6-DOF) large motion serial robot with microgrippers, a hexapod 6-DOF precision alignment worktable and a vision system whose optical axis of the microscope is parallel with the horizontal plane. A prism with special coating is fixed in front of the objective lens; thus, two parts’ Figures, namely the images of target and base part, can be acquired simultaneously. The relative discrepancy between the two parts can be calculated from image plane coordinate instead of calculating space transformation matrix. Therefore, the traditional calibration method cannot be applied in this microassembly system. An improved calibration method including the check corner detection solves the distortion coefficient conversely. This new way can detect the corner at sub-pixel accuracy. The experiment proves that the assembly accuracy of the coaxial microassembly system which has been calibrated by the new method can reach micrometer level.

Findings

The calibration results indicate that solving the distortion conversely could improve the assembly accuracy of MSCA.

Originality/value

The paper provides certain calibration methodological guidelines for devices with 2 dimensions or 2.5 dimensions, such as microelectromechanical systems devices, using MSCA.

Details

Assembly Automation, vol. 34 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 12 November 2013

Yancang Li, Chenguang Ban and Rouya Li

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been…

Abstract

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been enlightened by the behavior of ant colony's searching for food, positive feedback construction and distributed computing combined with certain heuristics are adopted in the algorithm, which makes it easier to find better solution. This paper introduces a series of ant colony algorithm and its improved algorithm of the basic principle, and discusses the ant colony algorithm application situation. Finally, several problems existing in the research and the development prospect of ACO are reviewed.

Details

World Journal of Engineering, vol. 10 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 February 2016

Xin Ye, Pan Liu, Zhijing Zhang, Chao Shao and Yan Li

The purpose of this paper is to analyze the sensitivity of the motion error parameters in microassembly process, thereby improving the assembly accuracy. The motion errors of the…

Abstract

Purpose

The purpose of this paper is to analyze the sensitivity of the motion error parameters in microassembly process, thereby improving the assembly accuracy. The motion errors of the precision motion stages directly affect the final assembly quality after the machine visual alignment.

Design/methodology/approach

This paper presents the error parameters of the in-house microassembly system with coaxial alignment function, builds the error transfer model by the multi-body system theory, analyzes the error sensitivity on the sensitive direction using the Sobol method, which was based on variance, and then gets the ones which made a great degree of influence. Before the sensitivity analyzing, parts of the error sources have been measured to obtain their distribution ranges.

Findings

The results of the sensitivity analysis by the Sobol method, which was based on variance, are coincident with the theoretical analysis. Besides, the results provide a reference for the error compensation in control process, for the selection of the precision motion stages and for the installation index of the motion stages of the assembly system with coaxial alignment.

Originality/value

This kind of error sensitivity analysis method is of great significance for improving the assembly accuracy after visual system positioning, and increasing efficiency from the initial motion stage selection to final error compensation for designers. It is suitable for general precision motion systems be of multi-degree of freedom, for the method of modeling, measuring and analyzing used in this paper are all universal and applicative.

Details

Assembly Automation, vol. 36 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

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