Ming Liu, Shan Cao and Shuliang Cao
The modeling of interphase forces plays a significant role in the numerical simulation of gas–liquid flow in a rotodynamic multiphase pump, which deserves detailed study.
Abstract
Purpose
The modeling of interphase forces plays a significant role in the numerical simulation of gas–liquid flow in a rotodynamic multiphase pump, which deserves detailed study.
Design/methodology/approach
Numerical analysis is conducted to estimate the influence of interphase forces, including drag force, lift force, virtual mass force, wall lubrication force and turbulent dispersion force.
Findings
The results show that the magnitude of the interphase forces can be sorted by: drag force > virtual mass force > lift force > turbulent dispersion force > wall lubrication force. The relations between interphase forces and velocity difference of gas–liquid flow and also the interphase forces and gas volume fraction are revealed. The distribution characteristics of interphase forces in the passages from impeller inlet to diffuser outlet are illustrated and analyzed. According to the results, apart from the drag force, the virtual mass force, lift force and turbulent dispersion force are required, whereas wall lubrication force can be neglected for numerical simulation of gas–liquid flow in a rotodynamic multiphase pump. Compared with the conventional numerical method which considers drag force only, the relative errors of predicted pressure rise and efficiency based on the proposed numerical method in account of four major forces can be reduced by 4.95 per cent and 3.00 per cent, respectively.
Originality value
The numerical analysis reveals the magnitude and distribution of interphase forces inside multiphase pump, which is meaningful for the simulation and design of multiphase pump.
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Shan Cao, Faqing He and Jinwei Gao
Important reserves of oil and gas, which are left to be discovered and produced, are mainly concentrated in challenging locations and under severe conditions such as high pressure…
Abstract
Purpose
Important reserves of oil and gas, which are left to be discovered and produced, are mainly concentrated in challenging locations and under severe conditions such as high pressure (HP)/high temperature (HT). The presence of aggressive environments including H2S, CO2 and chlorides plus HP/HT causes a series of corrosion problems, which cost the oil industry billions of dollars a year. Thus, there is an increasing challenge for tubes (i.e. oil country tubular goods, for short, OCTG) used in producing oil and gas. The purpose of this study is to summarize different kinds of corrosion problems and their mitigation, to more efficiently protect OCTG from corrosion.
Design/methodology/approach
To effectively select proper mitigation methods, the mechanism of corrosion must be understood, which can be classified into four categories: sweet corrosion, sour corrosion, galvanic corrosion and microbiologically induced corrosion. Also, the effects of environmental and material factors on the corrosion rate are presented. Subsequently, current technology of mitigating these corrosion problems has been discussed, including the development of materials, application of chemical inhibitors and application of protective layers.
Findings
It is stressed that limits exist for each individual mitigation method; therefore, a careful balance between economic life of OCTG and safety in operation is required.
Originality/value
The main purpose of this essay is to give a brief review and detailed introduction and analysis about those technologies.
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This paper aims to present an associated methodology to evaluate the initial stress of coal-rock masses in steeply inclined coal seams.
Abstract
Purpose
This paper aims to present an associated methodology to evaluate the initial stress of coal-rock masses in steeply inclined coal seams.
Design/methodology/approach
On the basis of the real-time monitoring data in the field, the corresponding analytical analysis is carried out in consideration of the characteristics of topography and geology, so as to deduce the value of the initial stress in the study area and also give the analytical model of the initial stress field.
Findings
The authors identified feasibility of the initial stress level of coal-rock masses in steeply inclined coal seams, and revealed that exact acquisition on the displacement of surrounding rock was feasible to analyze the initial stress level of coal-rock masses by the back analytical method in the steeply inclined coal seams as a two-dimensional plane problem.
Originality/value
The calculation results including vertical stress, minimum horizontal principal stress and shearing stress were 7.057, 8.085 and 0.057 MPa, respectively. The KJ743 coal mine initial stress monitoring system was used to collect real-time initial stress data, which were used to check the accuracy of the analytical back results. The value of the vertical stress varied from 6.8 to 7.0 MPa, which is slightly smaller than the result of the back calculation. The minimum principal horizontal stress varied from 7.6 to 8.4 MPa, which is similar to the result of the back calculation.
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The purpose of this paper is to explore the internal interaction mechanism of marine scientific research and education, industrial structure upgrading and marine economic growth…
Abstract
Purpose
The purpose of this paper is to explore the internal interaction mechanism of marine scientific research and education, industrial structure upgrading and marine economic growth from a systematic perspective, based on which this work forecasts their future development trends.
Design/methodology/approach
In this study, a multivariate grey model is applied to the prediction of marine scientific research and education, industrial structure upgrading and marine economic growth. Considering the impact of the COVID-19 on marine development, this paper introduces the weakening buffer operator into MGM(1,m) and constructs the AWBO-MGM(1,m) model. To verify the validity and accuracy of the new model, this paper uses AWBO-MGM(1,m), MGM(1,m), GM(1,N), GM(1,1), back propagation neural network and linear regression models for simulation and prediction based on the data from 2010 to 2021, respectively.
Findings
From the theoretical perspective, the development of marine scientific research and education can accelerate industrial upgrading and promote marine economic growth by providing high-quality talents, promoting marine science and technology progress and reducing transaction costs; while the upgrading of marine industrial structure and marine economic growth can promote the development of marine scientific research and education by guiding social capital, enhancing talent demand and stimulating market vitality. From the empirical analysis, the AWBO-MGM(1,m) model can effectively deal with epidemic shocks and has higher fitting and prediction accuracy than the other five comparative models.
Practical implications
The government should pay attention to the construction of marine scientific research and education, so as to provide high-quality talents and advanced scientific research results for the high-quality development of marine economy. On the basis of using science and technology to firmly build the primary and secondary marine industries, the government should actively guide the labor, capital and other factors of production to the tertiary industry, thereby promoting the optimization and upgrading of marine industrial structure.
Originality/value
On the one hand, the interplay mechanism of marine scientific research and education, industrial structure upgrading and marine economic growth is analyzed from a systematic perspective; on the other hand, the enhanced AWBO-MGM(1,m) possesses higher forecasting performance and is applicable to the systemic multivariate forecasting problem in the presence of outstanding external shocks.
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Paula Castro Pires de Souza Chimenti, Marco Aurelio de Souza Rodrigues, Marcelo Guedes Carneiro and Roberta Dias Campos
Through a literature review, a gap has been identified regarding the role of competition as a driver of social network (SN) usage. This study aims to design to address this gap…
Abstract
Purpose
Through a literature review, a gap has been identified regarding the role of competition as a driver of social network (SN) usage. This study aims to design to address this gap, seeking motivators for SN usage based on how SN consumption may be related to users’ experience of competition. Therefore, the purpose of this study is to investigate the influence of competition in social media usage.
Design/methodology/approach
The authors used an exploratory qualitative approach, conducting a set of focus groups with young social media users. Data was analyzed with software.
Findings
Two new drivers for SN use are proposed, namely, competition and collective narrative.
Research limitations/implications
This is an exploratory study, and it does not seek to generalize results or quantify causal relationships among variables.
Practical implications
This paper offers SN managers a deeper understanding of key growth drivers for these media.
Social implications
This research can help society understand and debate the impacts of SNs on users’ lives, providing insights into drivers of excessive usage.
Originality/value
This paper proposes the following two SN usage drivers yet to be described in the literature: competition and collective narrative.
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Jan Černý, Martin Potančok and Elias Castro Hernandez
The study aims to expand on the concept of an early warning system (EWS) by introducing weak-signal detection, human-in-the-loop (HIL) verification and response tuning as integral…
Abstract
Purpose
The study aims to expand on the concept of an early warning system (EWS) by introducing weak-signal detection, human-in-the-loop (HIL) verification and response tuning as integral parts of an EWS's design.
Design/methodology/approach
The authors bibliographically highlight the evolution of EWS over the last 30+ years, discuss instances of EWSs in various types of organizations and industries and highlight limitations of current systems.
Findings
Proposed system to be used in the transforming of weak signals to early warnings and associated weak/strong responses.
Originality/value
The authors contribute to existing literature by presenting (1) novel approaches to dealing with some of the well-known issues associated with contemporary EWS and (2) an event-agnostic heuristic for dealing with weak signals.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-11-2020-0513.
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Yuxiang Hong, Jiaqing Zhao, Jian Yu and Huihui Wang
Enhancing the initiative and enthusiasm of emergency preparedness behaviors among Medical and Health Organization (MHO) staff is an effective measure to prevent and reduce losses…
Abstract
Purpose
Enhancing the initiative and enthusiasm of emergency preparedness behaviors among Medical and Health Organization (MHO) staff is an effective measure to prevent and reduce losses from emergencies. In this study, emergency preparedness behavioral intentions were divided into noncooperative behavioral intentions (EPNCBI) and cooperative behavioral intentions (EPCBI) to discuss the impact brought by quality of life (QoL). The mediating effects of psychological capital (PsyCap) and perceived organizational support (POS) were also considered.
Design/methodology/approach
A web-based questionnaire was used for MHO staff in China, and a structural equation analysis of the data collected from 243 participants was conducted to test the hypotheses.
Findings
The empirical results reveal that: (1) QoL had a positive effect on EPNCBI, PsyCap and POS; (2) PsyCap had a positive effect on EPNCBI and EPCBI; (3) POS had a positive effect on PsyCap and EPCBI; (4) PsyCap mediated the relationship between QoL and EPNCBI, and the relationship between POS and EPNCBI; (5) PsyCap and POS mediated the relationship between QoL and EPCBI.
Practical implications
Improving MHO staff’s QoL is an effective way to enhance positive behavioral outcomes. Furthermore, these findings could provide managers with valuable insight focusing their limited resources on enhancing the emergency preparedness of MHO staff by reinforcing the level of PsyCap and POS.
Originality/value
This study provides important updated considerations for the application of positive psychology in the field of emergency preparedness.
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Yang Liu, Yuefan Hu, Dongxiang Xie, Yongjie Zhang and Jianqiang Chen
The paper aims to propose a generation approach for unstructured surface mesh to speed up mesh generation.
Abstract
Purpose
The paper aims to propose a generation approach for unstructured surface mesh to speed up mesh generation.
Design/methodology/approach
The paper proposes a lightweight interactive generation approach for unstructured surface mesh and presents several key technologies to support this approach.
Findings
The experimental results show that the proposed approach is feasible for unstructured meshes and it can accelerate the mesh generation process.
Research limitations/implications
More geometric defects should be covered, and more convenient and efficient interactive means need to be provided.
Practical implications
The proposed approach and key technologies are implemented in NNW-GridStar.UG, which is the unstructured version of the mesh generation software of National Numerical Windtunnel (NNW).
Originality/value
This paper proposes a lightweight interactive approach for unstructured surface mesh generation, which can speed up mesh generation.
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Yuqiang Cao, Zhuoan Feng, Meiting Lu and Yaowen Shan
This paper aims to provide a critical discussion of the application of the research pitching template developed by Professor Robert Faff to a research topic of tax avoidance and…
Abstract
Purpose
This paper aims to provide a critical discussion of the application of the research pitching template developed by Professor Robert Faff to a research topic of tax avoidance and firm risk. This letter provides a brief commentary on using the pitching template and discusses personal reflections on the pitching process.
Design/methodology/approach
This pitching research letter applies Faff’s pitching template and provides a critical commentary of the pitching process.
Findings
The team found that Faff’s pitching template is a valuable tool for conceiving research ideas. It helped the authors to identify, develop and articulate key aspects of the project. Further, they believe that completing the template was a beneficial and rewarding exercise, especially for early-career researchers.
Originality/value
This pitching research letter is tied to the team’s research idea that was pitched at the 2020 AFAANZ “Shark Tank” event. It provides original commentary on the use of Faff’s pitching template. It is not meant to retrofit published papers.
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Jianbo Song, Wencheng Cao and Yuan George Shan
This study uses data from the Chinese banking sector to explore the relationship between green credit and risk-taking in commercial banks. It also examines whether the level of…
Abstract
Purpose
This study uses data from the Chinese banking sector to explore the relationship between green credit and risk-taking in commercial banks. It also examines whether the level of regional green development acts as a moderator regarding this relationship.
Design/methodology/approach
Using a dataset composed of annual observations from 57 Chinese commercial banks between 2008 and 2021, this study employs both piecewise and curvilinear models.
Findings
Our results indicate that when the scale of green credit is low (<0.164), it increases the risk-taking of commercial banks. Conversely, when the scale of green credit is high (>0.164), it reduces the risk-taking of commercial banks. Moreover, this nonlinear relationship impact exhibits bank heterogeneity. Furthermore, the results show that the level of regional green development and local government policy support negatively moderate the relationship between green credit and commercial bank risk-taking. Furthermore, we find that green credit can directly enhance the net interest margin of commercial banks.
Originality/value
This study is the first to provide evidence of a nonlinear relationship between green credit and risk-taking in commercial banks, and it identifies the significant roles of regional green development level and local government policy support in the Chinese context.