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Article
Publication date: 5 August 2019

Wei-Hai Yuan, Wei Zhang, Beibing Dai and Yuan Wang

Large deformation problems are frequently encountered in various fields of geotechnical engineering. The particle finite element method (PFEM) has been proven to be a promising…

396

Abstract

Purpose

Large deformation problems are frequently encountered in various fields of geotechnical engineering. The particle finite element method (PFEM) has been proven to be a promising method to solve large deformation problems. This study aims to develop a computational framework for modelling the hydro-mechanical coupled porous media at large deformation based on the PFEM.

Design/methodology/approach

The PFEM is extended by adopting the linear and quadratic triangular elements for pore water pressure and displacements. A six-node triangular element is used for modelling two-dimensional problems instead of the low-order three-node triangular element. Thus, the numerical instability induced by volumetric locking is avoided. The Modified Cam Clay (MCC) model is used to describe the elasto-plastic soil behaviour.

Findings

The proposed approach is used for analysing several consolidation problems. The numerical results have demonstrated that large deformation consolidation problems with the proposed approach can be accomplished without numerical difficulties and loss of accuracy. The coupled PFEM provides a stable and robust numerical tool in solving large deformation consolidation problems. It is demonstrated that the proposed approach is intrinsically stable.

Originality/value

The PFEM is extended to consider large deformation-coupled hydro-mechanical problem. PFEM is enhanced by using a six-node quadratic triangular element for displacement and this is coupled with a four-node quadrilateral element for modelling excess pore pressure.

Details

Engineering Computations, vol. 36 no. 9
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 2 April 2019

Xiaohong Yuan, Qufu Wei, Huizhen Ke, Zujian Huang and Dongsheng Chen

The purpose of this paper is to prepare structural colors of fabrics coated with Silver/Zinc Oxide (Ag/ZnO) composite films by magnetron sputtering and analyze the relationship…

262

Abstract

Purpose

The purpose of this paper is to prepare structural colors of fabrics coated with Silver/Zinc Oxide (Ag/ZnO) composite films by magnetron sputtering and analyze the relationship between the colors and the thickness of Zinc Oxide (ZnO) film in Ag/ZnO composite film and the photocatalytic property of the fabrics coated with Ag/ZnO composite film.

Design/methodology/approach

Ag/ZnO composite films deposited on polyester fabrics were prepared by magnetron sputtering technology. The structural colors of textiles coated with Ag/ZnO composite films and the relationship between the colors and Ag/ZnO composite films were analyzed, and the photocatalytic property of Ag/ZnO composite films was also discussed.

Findings

The results indicated that the colors varied with the thicknesses of the ZnO film in Ag/ZnO composite films. The reactive sputtering time of ZnO film was 5, 8, 10 and 14 min, respectively, and the colors of the corresponding fabrics were purple, blue, blue-green and yellow. Meanwhile, the polyester fabrics coated with Ag/ZnO composite films showed the excellent photocatalytic properties, and silver (Ag) films deposited under the ZnO films in Ag/ZnO composite films could also improve the photocatalytic activities of ZnO films, and the formaldehyde degradation rates was 77.5%, which was higher than the 69.9% for the fabrics coated only with the ZnO film.

Originality/value

The polyester fabrics coated with Ag/ZnO composite films not only created various structural colors using change the thicknesses of the ZnO film, but also achieved the multifuctionality, which will have a broad application prospect in textile fields.

Details

International Journal of Clothing Science and Technology, vol. 31 no. 4
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 25 March 2019

Wei Zhang, Peitong Cong, Kang Bian, Wei-Hai Yuan and Xichun Jia

Understanding the fluid flow through rock masses, which commonly consist of rock matrix and fractures, is a fundamental issue in many application areas of rock engineering. As the…

218

Abstract

Purpose

Understanding the fluid flow through rock masses, which commonly consist of rock matrix and fractures, is a fundamental issue in many application areas of rock engineering. As the equivalent porous medium approach is the dominant approach for engineering applications, it is of great significance to estimate the equivalent permeability tensor of rock masses. This study aims to develop a novel numerical approach to estimate the equivalent permeability tensor for fractured porous rock masses.

Design/methodology/approach

The radial point interpolation method (RPIM) and finite element method (FEM) are coupled to simulate the seepage flow in fractured porous rock masses. The rock matrix is modeled by the RPIM, and the fractures are modeled explicitly by the FEM. A procedure for numerical experiments is then designed to determinate the equivalent permeability tensor directly on the basis of Darcy’s law.

Findings

The coupled RPIM-FEM method is a reliable numerical method to analyze the seepage flow in fractured porous rock masses, which can consider simultaneously the influences of fractures and rock matrix. As the meshes of rock matrix and fracture network are generated separately without considering the topology relationship between them, the mesh generation process can be greatly facilitated. Using the proposed procedure for numerical experiments, which is designed directly on the basis of Darcy’s law, the representative elementary volume and equivalent permeability tensor of fractured porous rock masses can be identified conveniently.

Originality/value

A novel numerical approach to estimate the equivalent permeability tensor for fractured porous rock masses is proposed. In the approach, the RPIM and FEM are coupled to simulate the seepage flow in fractured porous rock masses, and then a numerical experiment procedure directly based on Darcy’s law is introduced to estimate the equivalent permeability tensor.

Details

Engineering Computations, vol. 36 no. 3
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 9 April 2018

Wei Yuan, Guangneng Dong, Kwai Sang Chin, Meng Hua and Qianjian Guo

Streak defect and dynamic harmonic excitation (DHE) loading play important roles in machine operating conditions. The purpose of this paper was to assess the effects of streak…

103

Abstract

Purpose

Streak defect and dynamic harmonic excitation (DHE) loading play important roles in machine operating conditions. The purpose of this paper was to assess the effects of streak defect and DHE loading on the tribological properties of surface-contact friction pairs, for example the differential gear end-face on the washer, via experimental investigation.

Design/methodology/approach

Streak defect was artificially introduced into the washer surface, which was loaded with DHE loads produced by a spring-connecting weight system. The wear scar of the washers and the monitored friction force signals were respectively scanned using scanning electron microscope (SEM) and analyzed using wavelet simulation.

Findings

The friction force curves, SEM images and discrete wavelet transform results indicate that DHE loading tends to increase friction force, to accelerate plowing damages and result in side-flow of material and plastic deformation on the surfaces of the washer. Whereas, streak oil-channel textures on washer specimen can be machined to modify the lubrication condition in the running-in stage so as to improve the tribological properties of the sliding pairs which were even subjected to DHE loading.

Originality/value

On the basis of this thesis research, the effect of streak defect and DHE loading on tribological performance of surface-contact sliding pairs is discussed. The results of wear form and friction state with the effect of streak defect and DHE loading facilitate to optimize the operating condition of mechanical parts.

Details

Industrial Lubrication and Tribology, vol. 70 no. 3
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 2 March 2023

Wei-Yuan Lo, Yu-Kai Lin, Hsiang-Ming Lee and Tsui-Yau Liu

This study aims to use “both–and” thinking of Yin-Yang philosophy to extend the field of leadership literatures and explore the influences of paradoxical leadership and emotional…

710

Abstract

Purpose

This study aims to use “both–and” thinking of Yin-Yang philosophy to extend the field of leadership literatures and explore the influences of paradoxical leadership and emotional intelligence on organizational identification and turnover intentions of nurses.

Design/methodology/approach

The authors adopted a cross-sectional survey completed by 285 nurses in Taiwan. SPSS 22, PROCESS and AMOS 21 were used for data analysis.

Findings

The results reveal that paradoxical leadership has a significant positive relationship with nurses’ organizational identification and a significant negatively relationship with their turnover intentions, and organizational identification partially mediated the relationship between paradoxical leadership and turnover intentions. The results further show that emotional intelligence strengthens the effect of paradoxical leadership on organizational identification, and paradoxical leadership had a stronger indirect effect on turnover intentions through organizational identification under strong emotional intelligence.

Originality/value

Paradoxical leadership can strengthen managers’ abilities in dealing with interrelated and substantial issues and correspond to organizing and belonging paradoxes in holistic thinking processes. Health-care organizations must shape a coordinated institution and offer training initiatives to increase managers’ ability and attitude to control organizational rules and procedures while allowing employees’ flexibility and autonomy according to the requirements of the situation, which will maintain both organizational short-term benefits and long-term growth.

Details

Leadership in Health Services, vol. 36 no. 3
Type: Research Article
ISSN: 1751-1879

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Article
Publication date: 9 February 2024

Hsiang-Ming Lee, Ya-Hui Hsu, Tsai Chen, Wei-Yuan Lo and Wei-Chun Chien

The purpose of this study is to understand the effect of different brand positions (underdog vs top dog) and comparative advertising on consumers’ brand attitudes. Additionally…

573

Abstract

Purpose

The purpose of this study is to understand the effect of different brand positions (underdog vs top dog) and comparative advertising on consumers’ brand attitudes. Additionally, this study also aims to demonstrate the effects of inspiration, self-relevance and empathy on the relationship between brand positioning and comparative advertising.

Design/methodology/approach

A two-by-three factorial design was employed with brand positions (underdog vs top dog) and three types of comparative advertising (noncomparative, indirect comparative and direct comparative) as the independent variables. Inspiration serves as the mediator, while self-relevance and empathy act as moderators and brand attitude is the dependent variable.

Findings

The results show that different brand positions significantly affect brand attitudes, with respondents having a better brand attitude toward the underdog brand. Brand attitude is partially mediated by inspiration. Self-relevance moderates the relationship between brand positioning and brand attitude. However, brand positioning, comparative advertising and empathy do not have interaction effects.

Research limitations/implications

This study contributes to a better understanding of the effect of psychological variables on brand positioning and comparative advertising.

Practical implications

The results suggest that the underdog setting requires a real and honest story because consumers will spot a fake underdog story, which will damage consumer trust in the brand and harm the brand image.

Originality/value

There is a lack of research using psychological variables to demonstrate the effect of being the underdog brand. This study contributes to the literature by employing psychological variables to illustrate the effect of underdog positioning. These findings can help brands develop branding positioning strategies.

Details

Marketing Intelligence & Planning, vol. 42 no. 3
Type: Research Article
ISSN: 0263-4503

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Article
Publication date: 16 December 2024

Shufeng Tang, Jingfang Ji, Yun Zhi, Wei Yuan, Hong Chang, Xin Wang and Xiaodong Guo

Continuum robots offer unique advantages in various specialized environments, particularly in confined or hard-to-reach spaces. Inverse kinematics and real-time shape estimation…

60

Abstract

Purpose

Continuum robots offer unique advantages in various specialized environments, particularly in confined or hard-to-reach spaces. Inverse kinematics and real-time shape estimation constitute crucial aspects of closed-loop control for continuum robots, presenting challenging problems. This paper aims to present an inverse kinematics and shape reconstruction method, which relies solely on the knowledge of base and end positions and orientations.

Design/methodology/approach

Based on the constant curvature assumption, continuum robots are regarded as spatial curves composed of circular arcs. Using geometric relationships, the mathematical relationships between the arc chords, points on the bisecting plane and the coordinate axes are established. On this basis, the analytical solution of the inverse kinematics of the continuum robots is derived. Using the positions and orientations of the base and end of the continuum robots, the Levenberg–Marquardt algorithm is used to solve the positions of the cubic Bezier curves, and a new method of spatial shape reconstruction of continuum robots is proposed.

Findings

The inverse kinematics and spatial shape reconstruction simulation of the continuum robot are carried out, and the spatial shape measurement experimental platform for the continuum robot is constructed to compare the measured and reconstructed spatial shapes. The results show that the maximum relative error between the actual shape and the reconstructed shape of the continuum robot is 2.08%, which verifies the inverse kinematics and shape reconstruction model. Additionally, when the bending angle of a single bending section of the continuum robot is less than 135°, the shape reconstruction accuracy is higher.

Originality/value

The proposed inverse kinematics solution method avoids iterative solving, and the shape reconstruction model does not rely on mechanical models. It has the advantages of being simple to solve, highly accurate and fast in computation, making it suitable for real-time control of continuum robots.

Details

Industrial Robot: the international journal of robotics research and application, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 20 June 2016

Yuan Wei and Jing Zhao

This paper aims to deal with the problem of designing robot behaviors (mainly to robotic arms) to express emotions. The authors study the effects of robot behaviors from our…

918

Abstract

Purpose

This paper aims to deal with the problem of designing robot behaviors (mainly to robotic arms) to express emotions. The authors study the effects of robot behaviors from our humanoid robot NAO on the subject’s emotion expression in human–robot interaction (HRI).

Design/methodology/approach

A method to design robot behavior through the movement primitives is proposed. Then, a novel dimensional affective model is built. Finally, the concept of action semantics is adopted to combine the robot behaviors with emotion expression.

Findings

For the evaluation of this combination, the authors assess positive (excited and happy) and negative (frightened and sad) emotional patterns on 20 subjects which are divided into two groups (whether they were familiar with robots). The results show that the recognition of the different emotion patterns does not have differences between the two groups and the subjects could recognize the robot behaviors with emotions.

Practical implications

Using affective models to guide robots’ behavior or express their intentions is highly beneficial in human–robot interaction. The authors think about several applications of the emotional motion: improve efficiency in HRI, direct people during disasters, better understanding with human partners or help people perform their tasks better.

Originality/value

This paper presents a method to design robot behaviors with emotion expression. Meanwhile, a similar methodology can be used in other parts (leg, torso, head and so on) of humanoid robots or non-humanoid robots, such as industrial robots.

Details

Industrial Robot: An International Journal, vol. 43 no. 4
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 13 December 2021

Wei Yuan, Renfeng Yang, Jianyou Yu, Qunrong Zeng and Zechen Yao

Spray curing has become the preferred curing method for most cement concrete members because of its lower cost and sound effect. However, the spray curing quality of members is…

68

Abstract

Purpose

Spray curing has become the preferred curing method for most cement concrete members because of its lower cost and sound effect. However, the spray curing quality of members is vulnerable to random variation environment factors and anthropogenic interferences. This paper aims to introduce the machine learning algorithm into the spray curing system to optimize its control method to improve the spray curing quality of members.

Design/methodology/approach

The critical parameters affecting the spray curing quality of members were collected through experiments, such as the temperature and humidity of the member's surface, the temperature, humidity and wind speed of the environment. The C4.5 algorithm was used as a weak classifier algorithm, and the AdaBoost.M1 algorithm was used to cascade multiple weak classifiers to form a robust classifier according to the collected data.

Findings

The results showed that the model constructed by the AdaBoost.M1 algorithm had achieved higher accuracy and robustness among the two algorithms. Based on the classification model built by the AdaBoost.M1 algorithm, the spray curing system can cause automatic decision-making spray switching according to the member's real-time curing state and environment.

Originality/value

With the classification model constructed by the AdaBoost.M1 algorithm, the spray curing system can overcome the disadvantages that external factors greatly influence the current control method of the spray curing system, and the intelligent control of the spray curing system was realized to a certain extent. This paper provides a reference for applying machine learning algorithms in the intellectual transformation of bridge construction equipment.

Details

Construction Innovation , vol. 23 no. 1
Type: Research Article
ISSN: 1471-4175

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Article
Publication date: 29 June 2020

Hsiang-Ming Lee, Tsai Chen, Yu-Shan Chen, Wei-Yuan Lo and Ya-Hui Hsu

The purpose of this research is to survey whether consumer ethnocentrism and animosity will affect consumers' perceived betrayal and cause negative word-of-mouth (NWOM).

1872

Abstract

Purpose

The purpose of this research is to survey whether consumer ethnocentrism and animosity will affect consumers' perceived betrayal and cause negative word-of-mouth (NWOM).

Design/methodology/approach

This study conducted a 2 (consumer ethnocentrism) × 3 (consumer animosity) between-subject experiment design to test the hypotheses. Comprised of 380 respondents, this study used ANOVA to examine the data.

Findings

The results showed that if a brand violates the perception of fairness, ethnocentrism and animosity will have a positive effect on perceived betrayal. In addition, low consumer animosity revealed a significant consumer ethnocentrism effect and low ethnocentrism revealed a significant animosity effect, while the relationship between perceived betrayal and word of mouth is negative.

Originality/value

The current research adds to the understanding about how the reaction to a domestic brand's marketing strategies that are viewed as unfair and hurt the domestic consumers' expectations.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 33 no. 3
Type: Research Article
ISSN: 1355-5855

Keywords

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