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Article
Publication date: 4 April 2019

Yicheng Zhang, Chee Wei Phang, Rui Gu and Chenghong Zhang

The purpose of this paper is to investigate what may influence participation in mobile collaborative consumption (CC). In particular, the authors investigate the effects of…

Abstract

Purpose

The purpose of this paper is to investigate what may influence participation in mobile collaborative consumption (CC). In particular, the authors investigate the effects of individual sociability and psychological antecedents including enjoyment, social connection, altruistic motivation, reputation, trust and embarrassment on the participation intention in this emerging phenomenon, as well as their relationships.

Design/methodology/approach

Survey approach was employed to validate the research model.

Findings

Hedonic factor, i.e. enjoyment, and social-related factors including altruistic motivation, reputation and embarrassment emerge as important antecedents of participation in mobile CC. On top of these factors, individual sociability plays an important role, by acting as a direct antecedent of the dependent variable, while also influencing their perceived greater altruistic motivation and reputation from participating in the CC. Yet, sociability has no significant effect on perceived enjoyment and embarrassment associated with the activity, suggesting that addressing these factors may encourage individuals with low sociability to participate.

Originality/value

This study taps into mobile technology to support CC in daily consumption activities, and highlights the factors that influence people’s participation in such activities. More importantly, the findings suggest that while it is more likely for individuals with high sociability to participate in this emerging form of social activities, for consumers with low sociability, addressing the enjoyment aspect and embarrassment issue of the activities may nonetheless promote their participation.

Details

Internet Research, vol. 29 no. 5
Type: Research Article
ISSN: 1066-2243

Keywords

Article
Publication date: 28 September 2022

Zhiyong Fan, Zhen Zhao and Zhexu Liu

This paper aims to automatically generate load shedding sequences due to insufficient power supply, to ensure flight safety and complete flight task.

Abstract

Purpose

This paper aims to automatically generate load shedding sequences due to insufficient power supply, to ensure flight safety and complete flight task.

Design/methodology/approach

In this paper, a power allocation and load management model, including logical and physical submodels of the distribution system, is first established according to different requirements of the loads in different flight phase and the current total power supply. Then, an optimal load management scheme based on an improved ant colony algorithm is proposed to automatically generate load shedding sequences for both safety-critical and nonsafety critical loads, to achieve a reliable and safe power supply.

Findings

To verify the efficiency and feasibility of the algorithm, the proposed method is verified in a virtual simulation platform. Simulation result illustrates that the proposed algorithm is efficient and feasible.

Practical implications

The proposed method can provide guidance on load power supply when the civil aircraft is under abnormal power supply situation.

Originality/value

An optimal load management scheme is proposed by considering different requirements of the loads in different flight phase and the current total power supply.

Details

Aircraft Engineering and Aerospace Technology, vol. 95 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 13 May 2014

Tianmiao Wang, Chaolei Wang, Jianhong Liang and Yicheng Zhang

The purpose of this paper is to present a Rao–Blackwellized particle filter (RBPF) approach for the visual simultaneous localization and mapping (SLAM) of small unmanned aerial…

Abstract

Purpose

The purpose of this paper is to present a Rao–Blackwellized particle filter (RBPF) approach for the visual simultaneous localization and mapping (SLAM) of small unmanned aerial vehicles (UAVs).

Design/methodology/approach

Measurements from inertial measurement unit, barometric altimeter and monocular camera are fused to estimate the state of the vehicle while building a feature map. In this SLAM framework, an extra factorization method is proposed to partition the vehicle model into subspaces as the internal and external states. The internal state is estimated by an extended Kalman filter (EKF). A particle filter is employed for the external state estimation and parallel EKFs are for the map management.

Findings

Simulation results indicate that the proposed approach is more stable and accurate than other existing marginalized particle filter-based SLAM algorithms. Experiments are also carried out to verify the effectiveness of this SLAM method by comparing with a referential global positioning system/inertial navigation system.

Originality/value

The main contribution of this paper is the theoretical derivation and experimental application of the Rao–Blackwellized visual SLAM algorithm with vehicle model partition for small UAVs.

Details

Industrial Robot: An International Journal, vol. 41 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 11 August 2020

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

With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure…

Abstract

Purpose

With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure to a harsh environment of high-pressure hydrogen at medium temperature in practical application would still induce severe hydrogen uptake and eventually damage the mechanical properties of the steel. The study aims to evaluate the HE resistance of the steel under different tensile strain rates after hydrogen charging and analyze the hydrogen effect from atomic level.

Design/methodology/approach

This research studied the HE properties of 12Cr2Mo1R(H) steel by slow strain rate tests. Meanwhile, the effect of hydrogen on the structures and the mechanical properties of the simplified models of the steel was also investigated by first-principle calculations.

Findings

Experimental results showed that after hydrogen pre-charging in this work, hydrogen had little effect on the microstructure of the steel. The elongations and reduction of cross-sectional area of the samples reduced a lot, by contrast, the yield and tensile strengths changed slightly. The 12Cr2Mo1R(H) steel was not very susceptible to HE with a maximum embrittlement index of about 20.00%. First principles calculation results showed that after H dissolution, lattice distortion occurred and interstitial H atoms would preferentially occupy the tetrahedral interstitial site in bcc-Fe crystal and increase the stability of the supercells. With the increase of H atoms added into the simplified model, the steel still possessed a good ductility and toughness at a low hydrogen concentration, while the material would become brittle as the concentration of hydrogen continued to increase.

Originality/value

These finds can provide valuable information for subsequent HE studies on this steel.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

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…

148

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: 9 August 2019

Kun Zhang, Yicheng Fan, Xiaowei Luo, Xiaolang Chen, Chaolei Ban, Heming Zhao and Yiqing Chen

12Cr2Mo1R(H) steel is commonly used to make hot-wall hydrogenation reactors given its excellent mechanical properties and hydrogen embrittlement (HE) resistance. Longtime exposure…

211

Abstract

Purpose

12Cr2Mo1R(H) steel is commonly used to make hot-wall hydrogenation reactors given its excellent mechanical properties and hydrogen embrittlement (HE) resistance. Longtime exposure to high-pressure hydrogen at medium temperature would still severely damage the mechanical properties of the Cr-Mo steel with surface HICs caused by hydrogen adsorption and hydrogen uptake. The mechanisms of HE remain controversial and have not been fully understood so far.

Design/methodology/approach

The HE of the steel was investigated by slow strain rate test at different strain rates with in situ hydrogen charging. The diffusion coefficient of hydrogen in the steel is measured by electrochemical technology of hydrogen permeation. HIC cracks of the fractured specimens were captured with field emission SEM equipped with an electron backscatter diffraction system.

Findings

Results showed that the hydrogen led to the plasticity of the samples reduced significantly, together with the distinct work hardening behavior induced by hydrogen charging during plastic flow stage. The fracture of in situ charged sample changes from quasi-cleavage to intergranular fracture with the decreasing of strain rates, which indicates that the steel become more susceptible to hydrogen. High densities of dislocations and deformation are found around the crack, where grains are highly sensitive to HIC. Grains with different Taylor factor are more susceptible to intergranular crack.

Originality/value

The results of the study would be helpful to a safer application of the steel.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 18 April 2023

Qiaoping Zhang, Jing Guo and Yicheng Wei

This study explored the mathematical dispositions of Hong Kong mathematics pre-service teachers (PSTs). It also constructed a mathematical disposition framework comprising their…

Abstract

Purpose

This study explored the mathematical dispositions of Hong Kong mathematics pre-service teachers (PSTs). It also constructed a mathematical disposition framework comprising their affective, cognitive and functional dispositions towards the subject.

Design/methodology/approach

Thirty-one participants completed three structured metaphor tasks and one open-ended metaphor task in which they shared their views on mathematics. Responses were examined qualitatively and quantitatively. Coding based on thematic analysis was utilized to summarize the specific contents of the mathematical dispositions expressed by the PSTs, and a 5-level scoring scale was employed to evaluate the strength of the dispositions as represented by different metaphor types.

Findings

The findings suggest that the mathematical dispositions of pre-service mathematics teachers were generally positive. However, the overall level was not high. The most prevalent metaphors used to describe mathematics were “rice”, “blue” and “dog”.

Research limitations/implications

Hong Kong mathematics PSTs' mathematical dispositions are examined by using metaphorical tasks. Three categories are identified: affective, cognitive and functional dispositions towards mathematics.

Originality/value

This study has proposed an original framework for describing mathematical disposition.

Details

Asian Education and Development Studies, vol. 12 no. 2/3
Type: Research Article
ISSN: 2046-3162

Keywords

Article
Publication date: 29 May 2023

Xingwei Li, Jingru Li, Jinrong He, Yicheng Huang, Xiang Liu, Jiachi Dai and Qiong Shen

The surging market demand for green construction materials has brought opportunities for construction materials enterprises' greenwashing behavior (GWB). This study aims to…

Abstract

Purpose

The surging market demand for green construction materials has brought opportunities for construction materials enterprises' greenwashing behavior (GWB). This study aims to establish the causal relationship among the influencing factors of GWB and reveal the key influencing factors from the perspective of Chinese construction materials enterprises under multi-agent interactions.

Design/methodology/approach

This study is based on stakeholder theory, resource-based theory and the green development behavior and performance of industrial enterprises (GDBP-IE). First, with the literature analysis, an index framework of the influencing factors of enterprises' GWB was constructed from five dimensions (including 15 factors): environmental regulation, public scrutiny, market environment, corporate resources and corporate green development (GD) performance. Second, the interactive relationship among influencing factors was obtained by a questionnaire survey. Finally, the data are processed and analyzed with the grey-DEMATEL (Decision-making Trial and Evaluation Laboratory) method.

Findings

Among the factors, corporate information transparency has the greatest impact on the other factors, and consumer green preferences are most influenced by others. The most critical and important factor is the corporate social performance factor. In China, corporate social performance, corporate information transparency, corporate size and media supervision are the key factors influencing the GWB of construction materials enterprises.

Originality/value

This study provides a new perspective on the literature related to GWB by considering multi-agent interactions and extends the evidence from the construction materials industry for research on the drivers or influencing factors of enterprises' bad environmental behavior. Furthermore, it adds insights from China for further research on the governance strategies of GWB in other countries.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 8 September 2022

Xingwei Li, Xiang Liu, Yicheng Huang, Jingru Li, Jinrong He and Jiachi Dai

The green innovation behavior of construction enterprises is the key to reducing the construction industry's carbon emissions and realizing the green transformation of the…

Abstract

Purpose

The green innovation behavior of construction enterprises is the key to reducing the construction industry's carbon emissions and realizing the green transformation of the construction industry. The purpose of this study is to reveal the evolutionary mechanism of green innovation behavior in construction enterprises.

Design/methodology/approach

This study is based on resource-based theory, Porter's hypothesis and signaling theory. First, a measurement model of the green innovation behavior of construction enterprises was constructed from three aspects: environmental regulation, enterprise resources and public opinion through hierarchical analysis. Then, the state values of the measurement model of green innovation behavior of construction enterprises were calculated through the time series data from 2011–2018. Finally, the Markov chain model was used to predict the evolutionary trend of green innovation behavior of construction enterprises, and the accuracy of the prediction effect of the Markov chain model was verified using the time series data of 2019.

Findings

The Markov chain model of green innovation behavior of construction enterprises constructed in this study has high accuracy. This model finds that the transition of the growth state of green innovation behavior in China's construction industry is fluid and predicts the evolution trend of the innovation behavior of construction enterprises. In the future, the green innovation behavior of construction enterprises has a probability of 70.17% to be in a continuous growth state and 40.27% to be in a rapid growth state.

Originality/value

Based on the Markov chain model of green innovation behavior of construction enterprises, this study finds that the transition of the growth state of green innovation behavior of construction enterprises in China has the characteristics of liquidity. In addition, it reveals the development process of the green innovation behavior of construction enterprises from 2011–2018 and predicts the evolution trend of the green innovation behavior of construction enterprises.

Details

Engineering, Construction and Architectural Management, vol. 31 no. 1
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 30 March 2020

Donghua Zhao, Tianqi Li, Beijun Shen, Yicheng Jiang, Weizhong Guo and Feng Gao

The purpose of this paper is to design and develop a rotary three-dimensional (3D) printer for curved layer fused deposition modeling (CLFDM), and discuss some technical…

Abstract

Purpose

The purpose of this paper is to design and develop a rotary three-dimensional (3D) printer for curved layer fused deposition modeling (CLFDM), and discuss some technical challenges in the development.

Design/methodology/approach

Some technical challenges include, but are not limited to, the machine design and control system, motion analysis and simulation, workspace and printing process analysis, curved layer slicing and tool path planning. Moreover, preliminary experiments are carried out to prove the feasibility of the design.

Findings

A rotary 3D printer for CLFDM has been designed and developed. Moreover, this printer can function as a polar 3D printer for flat layer additive manufacturing (AM). Compared with flat layer AM, CLFDM weakens the staircase effect and improves geometrical accuracy and mechanical properties. Hence, CLFDM is more suitable for parts with curved surfaces.

Research limitations/implications

Double extruders have brought improved build speed. However, this paper is restricted to complex process planning and mechanical structures, which may lead to collisions during printing. Meanwhile, the rotation range of the nozzle is limited by mechanical structures, affecting the manufacturing capability of complex curved surfaces.

Originality/value

A novel rotary 3D printer, which has four degrees of freedom and double extruders, has been designed and manufactured. The investigation on the prototype has proved its capability of CLFDM. Besides, this rotary 3D printer has two working modes, which brings the possibility of flat layer AM and CLFDM.

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