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Article
Publication date: 1 April 1956

An axial flow turbojet engine in which the mean direction of flow of working fluid past any moving blade is substantially free from radial components comprising a casing;…

Abstract

An axial flow turbojet engine in which the mean direction of flow of working fluid past any moving blade is substantially free from radial components comprising a casing; an air intake in said casing; a low‐pressure axial‐flow compressor mounted in said casing, connected directly to said air intake to receive air through it and having a plurality of rows of moving blades whereof the first row has a hub tip ratio between 0·4 and 0·5; a high‐pressure axial flow compressor mounted in said casing, connected directly to said low‐pressure compressor to receive substantially the whole of the air compressed by said low‐pressure compressor and having a plurality of rows of moving blades; combustion equipment mounted in said casing and connected directly to said high‐pressure compressor to receive substantially the whole of the air compressed by said high‐pressure compressor; a single‐stage axial‐flow high‐pressure turbine mounted in said casing, connected directly to said combustion equipment to receive the products of combustion, and drivingly connected to said high‐pressure compressor, the power developed by said high‐pressure turbine being substantially wholly absorbed by said high‐pressure compressor; and a single‐stage axial‐flow low‐pressure turbine mounted in said casing, connected directly to said high‐pressure turbine to receive the exhaust from it and drivingly connected to said low‐pressure compressor, the power developed by said low‐pressure turbine being substantially wholly absorbed by said low‐pressure compressor; in which engine the ratio of the tip diameter of said low pressure turbine to the tip diameter of said first row of moving blades of said low pressure compressor is between 1 and 1·1; and the ratio between the power absorbed by the high‐pressure compressor and the power absorbed by the low‐pressure compressor is between 2 and 2·5 and the tip diameter of said first row of moving blades of said low pressure compressor is greater than the tip diameter of any other row of moving blades of either of said compressors, and the tip diameter of said low pressure turbine is greater than the tip diameter of said high pressure turbine.

Details

Aircraft Engineering and Aerospace Technology, vol. 28 no. 4
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 11 January 2022

Tamaki Mitsuno and Ayaka Kai Yanagisawa

The present study obtained the topography of perceptible (a perfect-fit feeling) clothing pressures from the chest to groin, when a stretching material provided hoop…

Abstract

Purpose

The present study obtained the topography of perceptible (a perfect-fit feeling) clothing pressures from the chest to groin, when a stretching material provided hoop tension to the body surface of participants. Furthermore, the allowable pressure level was examined for the abdomen, which is pressed by underclothes on a daily basis.

Design/methodology/approach

Participants were nine women aged 21.3 ± 1.2 years. Each participant's perception of pressure while wearing the experimental band was obtained in a questionnaire using a visual analog scale. Clothing pressure was measured employing a hydrostatic pressure-balancing method as participants adjusted the band length themselves to achieve two conditions: a perfect-fit and tight-fit on the abdomen.

Findings

The range of comfortable clothing pressure tightening provided by a 2.5 cm-wide elastic band on the abdomen was 0–5.6 hPa for under the bust, waist and groin, and 4.4–9.3 hPa for the chest, lower waist and hips. A nerve plexus of the autonomic nervous system and arteries are distributed over the body surface of the former body parts, which were thus sensitive to tightening around the abdomen.

Originality/value

The topography of perceptible clothing pressure was obtained when stretching material provided hoop tension to the body surface of the participant. The results of a participant questionnaire agreed with clothing pressure obtained using a hydrostatic pressure-balancing method that has a short-time constant and sensitive resolution. Furthermore, allowable pressure levels were proposed.

Details

International Journal of Clothing Science and Technology, vol. 34 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 28 October 2022

Xianmiao Li, Zhenting Xu and Yuqin Hu

This study aims to explore the dual-path effects of challenge (CTP) and hindrance time pressure (HTP) on knowledge sharing, which provides theoretical reference for…

Abstract

Purpose

This study aims to explore the dual-path effects of challenge (CTP) and hindrance time pressure (HTP) on knowledge sharing, which provides theoretical reference for knowledge teams to carry out knowledge sharing smoothly.

Design/methodology/approach

This study collected two waves of data and surveyed 416 employees in China. Regression analysis, bootstrapping and structure equitation modeling was adopted to test the hypotheses.

Findings

CTP has a positive impact on employee knowledge sharing, while HTP has a negative impact on employee knowledge sharing. Self-efficacy plays a mediating role between CTP and knowledge sharing, and emotional exhaustion plays a mediating role between HTP and knowledge sharing. The perceived organizational support can moderate the relationship between CTP and self-efficacy and between HTP and emotional exhaustion.

Originality/value

This study explains the reasons for the academic controversy about the effect of time pressure, enhances the scholars’ attention and understanding of the dual-path mechanism between time pressure and knowledge sharing and augments the theoretical research of time pressure and knowledge sharing.

Details

Journal of Knowledge Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1367-3270

Keywords

Article
Publication date: 10 June 2021

Chunxiao Jiao, Jianghai Xu, Donglin Zou, Na Ta and Zhushi Rao

The purpose of this paper is to study the flow field characteristics of the micro-scale textured bearing surfaces using the lattice Boltzmann method based on the…

Abstract

Purpose

The purpose of this paper is to study the flow field characteristics of the micro-scale textured bearing surfaces using the lattice Boltzmann method based on the microscopic dynamics of the fluid.

Design/methodology/approach

Considering the inertia effects and the micro-scale effects, the models of a single micro-scale texture unit cell with different shapes and different film thickness ratios are established. The influence of pressure difference between inlet and outlet of the unit cell on flow characteristics is studied.

Findings

The surface pressure distribution, flow patterns and pressure contours in the flow field are obtained. The results reveal that the pressure difference has a significant influence on the characteristics of the micro-textured flow field.

Originality/value

The results have certain guiding significance for further step investigation on microscopic lubrication mechanism of the water-lubricated polymer bearings.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 6 September 2022

Abdullahi B. Saka, Daniel W.M. Chan and Saheed O. Ajayi

Although there has been a surge in the adoption of building information modelling (BIM) in the construction industry, the small and medium-sized enterprises (SMEs) are…

Abstract

Purpose

Although there has been a surge in the adoption of building information modelling (BIM) in the construction industry, the small and medium-sized enterprises (SMEs) are still struggling and perceive its adoption as risky. The SMEs in developing economies are especially on the disadvantaged side of the digital divide. Extant studies have focused on large firms and there are scanty studies on the influence of the external environments on BIM adoption in SMEs. Thus, this study espouses institutional theory (INT) to examine the influence of coercive, mimetic, and normative pressures on BIM awareness and adoption in SMEs.

Design/methodology/approach

A quantitative approach was employed, and data were collected from the Nigerian construction SMEs via an empirical questionnaire survey using a sequential stratified and convenient sampling method. Hypothesized relationships between the coercive, mimetic, and normative pressure and BIM in SMEs were empirically tested using the partial least squares structural equation modelling (PLS-SEM) technique and the model was validated with the “PLSpredict” procedure.

Findings

The results revealed that coercive and mimetic pressures significantly influence BIM adoption in SMEs while normative pressures have the strongest influence on BIM in SMEs. Also, BIM awareness is an important predictor of BIM adoption. The findings also shed light on the influence of firmographics on BIM awareness and adoption in Nigerian SMEs.

Originality/value

The study empirically validates the applicability of INT and highlights that BIM adoption is not only influenced by internal responses to the need for efficiency but also by external pressures. It implies a clear need for intentional isomorphic pressures in driving BIM adoption in SMEs. The study employs the INT to explain a phenomenon that has not been theoretically explored in the context of SMEs in developing economies. Lastly, the study provided valuable insights into driving BIM adoption, together with the effective practical implications for implementation and potential research areas for further studies.

Details

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

Keywords

Article
Publication date: 6 September 2022

Lexis Alexander Tetteh, Cletus Agyenim-Boateng and Samuel Nana Yaw Simpson

This paper aims to explore the role of public sectors auditors in strategically responding to institutional pressures to conduct a performance audit of Sustainable…

Abstract

Purpose

This paper aims to explore the role of public sectors auditors in strategically responding to institutional pressures to conduct a performance audit of Sustainable Development Goals (SDGs) implementation in Ghana.

Design/methodology/approach

To gather in-depth and rich empirical data, semi-structured interviews were conducted with 12 senior and middle management auditors of Ghana's Supreme Audit Institution (SAI).

Findings

The findings indicate that the International Organisation of Supreme Audit Institutions, the government, auditees, political executives and the Audit Service Board all exert institutional pressure on Ghana's audit of SDG implementation. In response to these pressures, the SAI deploys acquiescence, compromise and manipulation strategies that result in the coupling, and in some cases, the loose coupling of SDG audit practices.

Research limitations/implications

Observation method of data collection would have given the researchers first-hand knowledge of the role of auditors, the institutional pressures to SDG audit and the strategic response to the institutional pressures. The authors were unable to accompany the public sector auditors to their field audits. This would have aided in obtaining more detailed empirical data.

Practical implications

The findings suggest that external and internal factors affect public sector audit of SDG implementation. Because the SAI of Ghana is dependent on the central government for budgetary allocation and auditees for miscellaneous logistics, it is under coercive pressure to meet rent seeking demands of political executives. As a result, SAIs in emerging economies must revisit the other side of accountability by reinforcing a constructive dialogue with those held accountable, particularly politicians and auditees.

Originality/value

This study's contribution is the exploration and application of institutional theory and Oliver (1991) model for responding to institutional pressures to a novel research area, namely, SDG implementation audit by public sector auditors in an emerging economy.

Details

Journal of Applied Accounting Research, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0967-5426

Keywords

Article
Publication date: 23 September 2022

Hang-Wei Wan, Yu-Quan Wen and Qi Zhang

The reaction dynamics of combustible clouds at high temperatures and pressures are a common form of energy output in aerospace and explosion accidents. The cloud explosion…

Abstract

Purpose

The reaction dynamics of combustible clouds at high temperatures and pressures are a common form of energy output in aerospace and explosion accidents. The cloud explosion process is often affected by the external initial conditions. This study aims to numerically study the effects of airflow velocity, initial temperature and fuel concentration on the explosion behavior of isopropyl nitrate/air mixture in a semiconstrained combustor.

Design/methodology/approach

The discrete-phase model was adopted to consider the interaction between the gas-phase and droplet particles. A wave model was applied to the droplet breakup. A finite rate/eddy dissipation model was used to simulate the explosion process of the fuel cloud.

Findings

The peak pressure and temperature growth rate both decrease with the increasing initial temperature (1,000–2,200 K) of the combustor at a lower airflow velocity. The peak pressure increases with the increase of airflow velocity (50–100 m/s), whereas the peak temperature is not sensitive to the initial high temperature. The peak pressure of the two-phase explosion decreases with concentration (200–1,500 g/m3), whereas the peak temperature first increases and then decreases as the concentration increases.

Practical implications

Chain explosion reactions often occur under high-temperature, high-pressure and turbulent conditions. This study aims to provide prevention and data support for a gas–liquid two-phase explosion.

Originality/value

Sustained turbulence is realized by continuously injecting air and liquid fuel into a semiconfined high-temperature and high-pressure combustor to obtain the reaction dynamic parameters of a two-phase explosion.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 11 October 2022

Zhen Li, Soochan Choi and Jeffrey Yi-Lin Forrest

The purpose of this paper is to examine the effect of peer pressure on joint consumption decisions among emerging adults. Building on prospect theory and characteristics…

Abstract

Purpose

The purpose of this paper is to examine the effect of peer pressure on joint consumption decisions among emerging adults. Building on prospect theory and characteristics of emerging adulthood, the authors propose that influence from peers (i.e. informational and normative influence) serves as a channel to understand how peer pressure shapes joint consumer behaviors at different levels of social capital.

Design/methodology/approach

An online survey is distributed to the emerging adults, aged 18 to 25, in the south, west, east and middle of the USA. Construct validity and reliability are tested by using confirmatory factor analysis. Structural equation modeling is used to test the mediating and moderating effects.

Findings

The results show that social capital moderates the relationship between peer pressure and group-oriented consumer decisions, such that the relationship is positive in groups with high-level social capital but negative in groups with low-level social capital. Furthermore, such effects tend to be achieved via peer influence. And peer influence is stronger in groups with high-level social capital than those with low-level social capital.

Originality/value

The current literature has shown contradictory results: it is usually believed that emerging adults may conform to pressure and engage in group-oriented decisions; however, some research has reported the opposite result. To better understand this relationship, the authors aim at a group-level factor – perceived social capital – as a boundary condition. This research contributes to the young consumer decision-making literature by involving the interplay among peer pressure, perceived social capital and peer informational and normative influence.

Details

Young Consumers, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1747-3616

Keywords

Article
Publication date: 6 October 2022

Nikunj Kumar Jain, Piyush Choudhary, Abinash Panda, Sourabh Jain and Prasanta Kumar Dey

Globally, the oil and gas (OG) industries are under pressure from numerous stakeholders for their sustainable operations against the backdrop of climate change, ecological…

Abstract

Purpose

Globally, the oil and gas (OG) industries are under pressure from numerous stakeholders for their sustainable operations against the backdrop of climate change, ecological damage and social challenges. Drawing on the twin theoretical frameworks of the institutional theory and dynamic capability perspective, this study aims to examine the impact of the institutional pressures and dynamic capabilities on the overall sustainability performance of OG industry.

Design/methodology/approach

This study uses survey method to analyze the responses from 275 middle management professionals of OG industry in India using partial least squares structural equation modeling. Further, focused group discussions with the select industry leaders validate the empirical findings of this study.

Findings

The research reveals that both institutional pressures and firm’s dynamic capabilities have significant positive impact on its economic and environmental performances in OG sector in India. However, they do not have any impact on social performance, unlike earlier findings.

Research limitations/implications

The main limitation of the study is generalizability of the findings, given the cross-sectional design of the study.

Practical implications

Insights of this study will help regulators and policymakers in formulating effective regulatory and policy frameworks, besides creating awareness amongst the organizations to simultaneously focus on all the three aspects of sustainability performance.

Originality/value

The research has bearing on policy formulation and creating a regulatory ecosystem to ensure overall sustainability performance of OG industry in India.

Details

International Journal of Energy Sector Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1750-6220

Keywords

Article
Publication date: 9 September 2022

Yi-Chun Huang and Chih-Hsuan Huang

Prior research on green innovation has shown that institutional pressure stimulates enterprises to adopt green innovation. However, an institutional perspective does not…

Abstract

Purpose

Prior research on green innovation has shown that institutional pressure stimulates enterprises to adopt green innovation. However, an institutional perspective does not explain why firms that face the same amount of institutional pressure execute different environmental practices and innovations. To address this research gap, the authors linked institutional theory with upper echelons theory and organization performance to build a comprehensive research model.

Design/methodology/approach

A total of 800 questionnaires were issued. The final usable questionnaires were 195, yielding a response rate of 24.38%. AMOS 23.0 was used to analyze the data and examine the relationships between the constructs in our model.

Findings

Institutional pressures affected both green innovation adoption (GIA) and the top management team's (TMT's) response. TMT's response influenced GIA. GIA was an important factor affecting firm performance. Furthermore, TMT's response mediated the relationship between institutional pressure and GIA. Institutional pressures indirectly affected green innovation performance but did not influence economic performance through GIA. Finally, TMT's response indirectly impacted firm performance through GIA.

Originality/value

The authors draw on institutional theory, upper echelons theory, and a performance-oriented perspective to explore the antecedents and consequences of GIA. This study has interesting implications for leaders and managers looking to implement green innovation and leverage it for firm performance to out compete with market rivals as well as to make the changes in collaboration with many other companies including market rivals to gain success in green innovation.

Details

European Journal of Innovation Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1460-1060

Keywords

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