Zheng (Daniel) Duan, Christian Yao and Hongxia Qi
Extensive research has demonstrated the influence of job resources on mitigating the impact of high job demands on individual well-being. Still, little is known about how…
Abstract
Purpose
Extensive research has demonstrated the influence of job resources on mitigating the impact of high job demands on individual well-being. Still, little is known about how individuals use job resources to cope. This study advances job demands-resources (JD-R) theory by investigating the process of job resource utilization from a coping perspective.
Design/methodology/approach
This study is based on in-depth interviews with 32 Chinese senior executives using a Critical Incident Technique (CIT) for data collection and thematic analysis for data analysis.
Findings
Data analysis reveals a 2x2 matrix model of resource utilization, highlighting the relevance of internal and external job resources in coping and resource creation.
Practical implications
The findings suggest that work stress intervention should look beyond the organizational domain and assist senior executives in exploring and developing external resources for coping. Additionally, organizations should equip senior executives with sufficient support to create new job resources that effectively manage complicated job demands.
Originality/value
The results of this study extend the understanding of job resources by distinguishing internal and external job resources. It also provides a dynamic view of resource utilization, emphasizing the role of job crafting in creating adaptable job resources to meet job demands.
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Zhiqiang Zheng, Haibin Duan and Yimin Deng
The purpose of this paper is to propose a novel maximum power point track (MPPT) controller for a type of solar quad-copter to solve the problem of tracking the maximum power…
Abstract
Purpose
The purpose of this paper is to propose a novel maximum power point track (MPPT) controller for a type of solar quad-copter to solve the problem of tracking the maximum power point (MPP) when it works in nonuniform environment conditions.
Design/methodology/approach
The influence of uniform and nonuniform illumination and different temperatures results in the output characteristics of the solar array arising multiple local MPPs. To track the global MPP of the solar array on the designed solar quadcopter, a type of MPPT controller based on an improved pigeon-inspired optimization (PIO) algorithm is proposed.
Findings
A novel type of MPPT controller based on extended search PIO (ESPIO) algorithm, called ESPIO–MPPT controller, is introduced emphatically, which is used to extend the solar quadcopter’s flight time. The simulation experiments show that the ESPIO–MPPT controller can find the global MPP (GMPP) with smaller amplitudes of oscillation and less time cost.
Practical implications
The proposed solar quadcopter with ESPIO–MPPT controller has satisfactory flight performance which can greatly broaden its mission scope.
Originality/value
A type of efficient MPPT algorithm based on ESPIO is proposed for GMPP tracking of solar quadcopters in nonuniform environment conditions.
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Richard Regueiro, Zheng Duan and Beichuan Yan
– The purpose of this paper is to develop a concurrent multiscale computational method for granular materials in the quasi-static loading regime.
Abstract
Purpose
The purpose of this paper is to develop a concurrent multiscale computational method for granular materials in the quasi-static loading regime.
Design/methodology/approach
Overlapped-coupling between a micropolar linear elastic one-dimensional (1D) mixed finite element (FE) model and a 1D chain of Hertzian nonlinear elastic, glued, discrete element (DE) spheres is presented. The 1D micropolar FEs and 1D chain of DEs are coupled using a bridging-scale decomposition for static analysis.
Findings
It was found that an open-window DE domain may be coupled to a micropolar continuum FE domain via an overlapping region within the bridging-scale decomposition formulation for statics. Allowing the micropolar continuum FE energy in the overlapping region to contribute to the DE energy has a smoothing effect on the DE response, especially for the rotational degrees of freedom (dofs).
Research limitations/implications
The paper focusses on 1D examples, with elastic, glued, DE spheres, and a linear elastic micropolar continuum implemented in 1D.
Practical implications
A concurrent computational multiscale method for granular materials with open-window DE resolution of the large shearing region such as at the interface with a penetrometer skin, will allow more efficient computations by reducing the more costly DE domain calculations, but not at the expense of generating artificial boundary effects between the DE and FE domains.
Originality/value
Open-window DE overlapped-coupling to FE continuum domain, accounting for rotational dofs in both DE and FE methods. Contribution of energy from micropolar FE in overlap region to underlying DE particle energy.
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Yezhong Fang, Xiaotian Ji, Xingquan Zhang, Jun Wang, Bin Chen, Shiwei Duan, Jinyu Tong, Guangwu Fang and Shanbao Pei
The purpose of this paper is to investigate the dynamic forming process of the micro dent fabricated by laser shock processing on 2024-T3 aluminum alloy. The effect of laser pluse…
Abstract
Purpose
The purpose of this paper is to investigate the dynamic forming process of the micro dent fabricated by laser shock processing on 2024-T3 aluminum alloy. The effect of laser pluse energy on the deformation of micro dent was also discussed in detail.
Design/methodology/approach
It uses finite element analysis method and the corresponding laser shocking experiment.
Findings
The results demonstrate that the dynamic formation process of micro dent lasts longer in comparison with the shock wave loading time, and the depths of micro dents increase with the increasing laser energy. In addition, laser shocking with higher energy can result in more obvious pileup occurred at the outer edge of micro dent.
Originality/value
Surface micro dents can serve as fluid reservoirs and traps of the wear debris, which can decrease the effects of the wear and friction in rolling and sliding interfaces. The investigations can not only be propitious to comprehensively understand the forming mechanism of laser-shocked dent, but also be beneficial to get sight into the residual stress field induced by laser shocking.
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Christian Yao, Kaye Thorn, Zheng Duan and Nazim Taskin
– The purpose of this paper is to examine the relevance of personal and organisational factors contributing to workplace stress among Chinese migrants in New Zealand.
Abstract
Purpose
The purpose of this paper is to examine the relevance of personal and organisational factors contributing to workplace stress among Chinese migrants in New Zealand.
Design/methodology/approach
The study is based on surveys of 88 participants using the theoretical model of person-environment fit.
Findings
The results reveal that perceived fit of organisational factors has a significant impact on workplace stress outcomes including emotional well-being, work-related health, job performance and intention to quit. Further analysis also shows that personal factors, some as a result of acculturation, play a moderating effect on the perceived relationship between the organisation and workplace stress. Education, advanced language skills and building networks in the new community are all important factors to minimise stress.
Originality/value
From an organisational perspective, the study highlights the importance of understanding the factors that cause workplace stress, especially with a culturally diverse working population. This cross-sectional study could be furthered through the use of alternative cultural samples, and through the development of a longitudinal design. In short, this study of the work stress of Chinese migrants in New Zealand contributes to the field of knowledge providing exploratory insights for work stress research in human resource management.
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Xiaohan Xu, Xudong Huang, Ke Zhang and Ming Zhou
In general, the existing compressor design methods require abundant knowledge and inspiration. The purpose of this study is to identify an intellectual design optimization method…
Abstract
Purpose
In general, the existing compressor design methods require abundant knowledge and inspiration. The purpose of this study is to identify an intellectual design optimization method that enables a machine to learn how to design it.
Design/methodology/approach
The airfoil design process was solved using the reinforcement learning (RL) method. An intellectual method based on a modified deep deterministic policy gradient (DDPG) algorithm was implemented. The new method was applied to agents to learn the design policy under dynamic constraints. The agents explored the design space with the help of a surrogate model and airfoil parameterization.
Findings
The agents successfully learned to design the airfoils. The loss coefficients of a controlled diffusion airfoil improved by 1.25% and 3.23% in the two- and four-dimensional design spaces, respectively. The agents successfully learned to design under various constraints. Additionally, the modified DDPG method was compared with a genetic algorithm optimizer, verifying that the former was one to two orders of magnitude faster in policy searching. The NACA65 airfoil was redesigned to verify the generalization.
Originality/value
It is feasible to consider the compressor design as an RL problem. Trained agents can determine and record the design policy and adapt it to different initiations and dynamic constraints. More intelligence is demonstrated than when traditional optimization methods are used. This methodology represents a new, small step toward the intelligent design of compressors.
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Munish Gupta, Vikas Sharma and Kshitiz Jangir
Purpose: This study investigates the influence of inflation and oil price fluctuations on stock prices and returns. A thorough bibliometric analysis of research articles published…
Abstract
Purpose: This study investigates the influence of inflation and oil price fluctuations on stock prices and returns. A thorough bibliometric analysis of research articles published in the last 22 years has been conducted to achieve this objective.
Need for the Study: Inflation and oil prices are critical macroeconomic variables that significantly impact the economy, including the stock market. It is crucial for investors and policymakers to understand the complex relationship between these economic variables and the stock market.
Methodology: The study employed a bibliometric analysis to identify the most influential authors, institutions, and research themes related to the impact of inflation and oil prices on stock prices.
Findings: The study identified that the fluctuations of the stock market are significantly influenced by both inflation and oil prices. This relationship has been extensively studied in the literature, with several key research themes identified. These themes include the effects of inflation and oil prices on various sectors and industries, the role played by monetary and fiscal policy, and the impact of international trade and global economic conditions.
Practical Implications: The insights that have emerged have significant implications for investors and policymakers. It highlights the need for risk management strategies and mitigation of macroeconomic factors’ impact on stock prices.
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Bing Xu and Xiaowen Hu
– The purpose of this paper is to find alternative strategies to change negative output gaps in China.
Abstract
Purpose
The purpose of this paper is to find alternative strategies to change negative output gaps in China.
Design/methodology/approach
A path Philips curves approach is proposed to investigate output gaps, which develops hybrid Philips curves with the control variables of money, house prices and interest rates.
Findings
An alternative strategy to stop the decline in output gaps rate is to perform interest rate, house price, and money growth rate about 3, 1 and 15 percent, respectively. The results also indicate that only one of monetary increase, changes in interest rates, and house price adjustments are difficult to change the negative output gap.
Practical implications
Alternative strategies cannot only change the negative output gap, but also succeed in pushing the inflation rate down to 3 percent.
Originality/value
This study provides a new path Philips curves to simulate how the macroscopic control variables influence output and inflation. It provides a useful insight for stopping the decline in output gaps.
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Libiao Bai, Xiaoyan Xie, Yichen Sun, Xue Qu and Xiao Han
Assessing project criticality in a project portfolio (PP) is of great practical significance to improve robustness from damage. While project criticality assessment has increased…
Abstract
Purpose
Assessing project criticality in a project portfolio (PP) is of great practical significance to improve robustness from damage. While project criticality assessment has increased diversity in approaches, the understanding of vulnerable project impacts is still limited. To promote a better understanding of assessing project criticality, a vulnerability measurement model is constructed.
Design/methodology/approach
First, integrating the tasks, projects and corresponding relationships among them, a project portfolio network (PPN) is constructed. Second, the project's vulnerability is measured by combining the topological structure and functional attributes. Third, project criticality is assessed by the vulnerability measurement results. Lastly, the proposed model is applied in a numerical example to illustrate its suitability and effectiveness.
Findings
For academia, this study provides a novel perspective on project vulnerability measurement and expands project criticality assessment tools. For practitioners, the straightforward model provides an effective tool for assessing project criticality and contributes to enhancing project portfolio management (PPM).
Originality/value
The impact of the task on the project is considered in this study. Topological structure and functional attributes are also integrated for measuring project vulnerability due to the impact of random attacks in an uncertain environment, providing a new perspective on the requirements of project criticality assessment and the measurement of project vulnerability.