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1 – 8 of 8Mengyao Fan, Xiaojing Ma, Lin Li, Xinpeng Xiao and Can Cheng
In this paper, the complex flow evaporation process of droplet impact on the liquid film in a horizontal falling film evaporator is numerically studied based on smoothed particle…
Abstract
Purpose
In this paper, the complex flow evaporation process of droplet impact on the liquid film in a horizontal falling film evaporator is numerically studied based on smoothed particle hydrodynamics (SPH) method. The purpose of this paper is to present the mechanism of the water treatment problem of the falling film evaporation for the high salinity mine water in Xinjiang region of China.
Design/methodology/approach
To effectively characterize the phase transition problem, the particle splitting and merging techniques are introduced. And the particle absorbing layer is proposed to improve the nonphysical aggregation phenomenon caused by the continuous splitting of gas phase particles. The multiresolution model and the artificial viscosity are adopted.
Findings
The SPH model is validated qualitatively with experiment results and then applied to the evaporation of the droplet impact on the liquid film. It is shown that the larger single droplet initial velocity and the smaller single droplet initial temperature difference between the droplet and liquid film improve the liquid film evaporation. The heat transfer effect of a single droplet is preferable to that of multiple droplets.
Originality/value
A multiphase SPH model for evaporation after the droplet impact on the liquid film is developed and validated. The effects of different factors on liquid film evaporation, including single droplet initial velocity, single droplet initial temperature and multiple droplets are investigated.
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Zhijiang Wu, Yongxiang Wang and Mengyao Liu
The negative effects of job stress and burnout on construction professionals (CPs) at the construction site have been widely concern in the construction industry. The purpose of…
Abstract
Purpose
The negative effects of job stress and burnout on construction professionals (CPs) at the construction site have been widely concern in the construction industry. The purpose of this study is committed to explore the impact of job stress on CPs on the construction site, especially in the context of the widespread use of social media to express their emotions.
Design/methodology/approach
This study developed a job-related stress-burnout-health conditions-turnover intention (S-B-HT) framework to explore the direct and lagged effects of job stress, we also examined the moderating effects of online emotions, operationalized in terms of emotional intensity and expression pattern, on the relationship between job stress with job burnout under two evolution paths (i.e. health conditions or turnover intention). This study collected 271 samples through a survey questionnaire for empirical testing, and introduced structural equation models to validate the proposed conceptual model.
Findings
The results show that job stress has a significant positive effect on job burnout, and job burnout maintains a positive relationship with health conditions (or turnover intention) under the interference mechanism. Simultaneously, the online emotions expressed in social media have a positive moderating effect in two stages of the evolution path.
Practical implications
The findings of this study remind the project manager need to timely find and solve the job burnout characteristics of CPs due to excessive job stress, especially to prevent the accidental consequences caused by job burnout.
Originality/value
On this basis, this study provides an important value of using social media to express emotions for the project team to alleviate the adverse of professionals under job stress.
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Shinan Chang, Mengyao Leng, Hongwei Wu and James Thompson
The purpose of this paper is to present a new technique based on the combination of wavelet packet transform (WPT) and artificial neural networks (ANNs) for predicting the ice…
Abstract
Purpose
The purpose of this paper is to present a new technique based on the combination of wavelet packet transform (WPT) and artificial neural networks (ANNs) for predicting the ice accretion on the surface of an airfoil.
Design/methodology/approach
Wavelet packet decomposition is used to reduce the number of input vectors to ANN and to improve the training convergence. An ANN is developed with five variables (velocity, temperature, liquid water content, median volumetric diameter and exposure time) taken as input data and one dependent variable (the decomposed ice shape) given as the output. For the purpose of comparison, three different ANNs, back-propagation network (BP), radial basis function network (RBF) and generalized regression neural network (GRNN), are trained to simulate the wavelet packet coefficients as a function of the in-flight icing conditions.
Findings
The predicted ice accretion shapes are compared with the corresponding results from previously published NASA experimentation, LEWICE and the Fourier-expansion-based method. It is found that the BP network has an advantage on predicting the rime ice, and the RBF network is relatively suitable for the glaze ice, while the GRNN can be applied for both without classifying the specimens. Results also show an advantage of WPT in performing the analysis of ice accretion information and the prediction accuracy is improved as well.
Practical implications
The proposed method is open to further improvement and investment due to its small computational resource requirement and efficient performance.
Originality/value
The simulation method combining ANN and WPT outlined here can lay the foundation for further research relating to ice accretion prediction under different ice cloud conditions.
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Xiaohu Deng, Mengyao Fu, Shasha Deng, Chee-Wee Tan and Zhibin Jiang
Contemporary focus on infections and deaths in the event of pandemics may distract health institutions and medical practitioners from the psychosocial consequences of the…
Abstract
Purpose
Contemporary focus on infections and deaths in the event of pandemics may distract health institutions and medical practitioners from the psychosocial consequences of the outbreak in individuals. In light of the devastation, persistency and scarcity of pandemics, it is imperative to delve into individuals' psychological state and self-preservation instincts when confronted with the environmental danger arising from pandemic conditions and the environmental restrictions being imposed.
Design/methodology/approach
Guided by the self-preservation theory, the authors advance a research model to elucidate the moderated mediation effect of secondary traumatic stress on an individual's reactions when faced with environmental danger and restriction. The authors also consider the moderating influence of environmental restriction and media use diversity. The authors subsequently validated the research model via a survey with 2,016 respondents in China. The authors employed PLS-SEM to analyze the data and assess the hypothesized paths.
Findings
Analytical results revealed that secondary traumatic stress fully mediated the impact of environmental danger on external reliance but suppresses the mediating effects on internal reliance. The authors further confirmed that environmental restriction moderated the relationship between environmental danger and reliance. Furthermore, the authors attest to the moderating influence of media use diversity on the relationship between secondary traumatic stress and external reliance.
Originality/value
This study not only extends the theoretical lens of self-preservation to public health emergencies but also yields practical guidelines for coping with pandemics. Insights from this study can be harnessed to aid populations worldwide in coping and recovering from pandemics.
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Gang Li, Qiqi Zheng and Mengyao Xia
Due to the fact that most employees have been forced to work remotely during the lockdown resulting from the COVID-19 pandemic, there is great concern about how to alleviate…
Abstract
Purpose
Due to the fact that most employees have been forced to work remotely during the lockdown resulting from the COVID-19 pandemic, there is great concern about how to alleviate increased stress among employees through human resource (HR) practices. Drawing upon the job demands-control (JDC) model and the job demands-resources (JDR) model, this study empirically investigated the direct effect of HR practices on employee stress in enforced remote work and the mediating role of sources of stress (SoS) and sense of control (SoC).
Design/methodology/approach
Data were collected through an online survey platform called Wenjuanxing from March 15 to 22, 2020 in Hubei, China and from April 22 to 29, 2022 in Shanghai, China. Respondents scanned the QR code on WeChat to enter the platform. A total of 511 valid questionnaires were received with a response rate of 75.4%. After controlling demographic variables, the authors used the mediation modeling and PROCESS tool to test the proposed hypotheses.
Findings
HR practices negatively affect stress in enforced remote work among employees. Both SoS and SoC partially mediate the relationship between HR practices and stress. HR practices can alleviate stress via decreasing SoS and enhancing SoC, respectively. Moreover, employee care and training are found to be two key factors of HR practices to help employees alleviate stress in enforced remote work.
Originality/value
Lockdown as an extreme external condition has brought great challenges in employee work arrangement as well as HR practices. Although the relationship between HR practices and job stress was studied previously, there is a lack of research on the effects of HR practices on stress in enforced remote work due to lockdown. It advances knowledge on HR practices' stress-reducing effect in the context of remote work and provides suggestions for HR practitioners on ways of alleviating employee stress in remote work.
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