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Article
Publication date: 6 March 2017

Davood Ramesh, Hasan Karimi M. and Massoud Shahheidari

The purpose of this paper is to introduce new and modified “staged combustion” cycles in the form of engineering algorithm as a possible propulsion contender for future aerospace…

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Abstract

Purpose

The purpose of this paper is to introduce new and modified “staged combustion” cycles in the form of engineering algorithm as a possible propulsion contender for future aerospace vehicle to achieve the highest possible “total impulse” to “mass” of propulsion system.

Design/methodology/approach

In this regard, the mathematical cycle model is formed to calculate the engine’s parameters. In addition, flow conditions (pressure, temperature, flow rate, etc). in the chamber, nozzle and turbopump are assessed based on the results of turbo machinery power balance and initial data such as thrust, propellant mixture ratio and specifications. The developed code has been written in the modern, object-oriented C++ programming language.

Findings

The results of the developed code are compared with the Russian RD180 engine which demonstrates the superiority and capability of new “thermodynamic diagrams”.

Research limitations/implications

This algorithm is under constraint to control the critical variation of combustion pressure, turbine rpm, pump cavitation and turbine temperature. It is imperative to emphasize that this paper is limited to “oxidizer-rich staged combustion” engines with “single pre-burner”.

Originality/value

This study sheds light on using fuel booster turbopump and the second-stage fuel pump to moderate the effect of cavitation on pumps which reduces tank pressure and, as a consequence, decreases the propulsion system weight.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 2
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 5 January 2015

Ehsan A. Tahmasebi and Hasan Karimi M.

– This study aims to present a method for conceptual design and simulation of hybrid propellant motors.

314

Abstract

Purpose

This study aims to present a method for conceptual design and simulation of hybrid propellant motors.

Design/Methodology/Approach

The design methodology is based on previous studies and thermo-physical governor relations, and also a computational code that was derived to simulate the performance of designed system.

Findings

Conceptual design algorithm for space hybrid propellant systems and method of performance simulation are findings of this study.

Practical implications

Results of this study are applicable for design process of space systems with hybrid propulsion. Also, simulation results can help the users to improve the performance weaknesses.

Originality/value

This study shows the implementation of present algorithm for a specified space mission and also study on variation of performance parameters.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 1
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 11 July 2022

Abdul Habib Zaray, Abid Hasan, Sparsh Johari, Parvez Ahmad Hashmat and Kumar Neeraj Jha

The poor quality of construction work in war-affected regions is a significant issue. The large-scale destruction to the existing infrastructure from the war necessitates cost and…

422

Abstract

Purpose

The poor quality of construction work in war-affected regions is a significant issue. The large-scale destruction to the existing infrastructure from the war necessitates cost and time-efficient delivery of construction projects during and post-war to bring normalcy to affected lives and places. Consequently, there is always a tendency to finish construction projects in the shortest possible time on a limited budget without following the proper quality management processes. However, the poor quality of construction projects continues to affect the country's development, growth, credibility, reputation, and public safety for several years after the war. To this end, the present study was conducted to evaluate the significant attributes and factors contributing to the poor quality of construction projects in the war-affected Afghan construction sector.

Design/methodology/approach

A total of 31 attributes influencing construction project quality were ranked based on 110 completed survey responses collected from Afghan construction professionals. Moreover, independent samples t-test, Spearman's rank correlation test, and exploratory factor analysis were conducted.

Findings

The study found a moderate consensus between clients and contractors on attributes' rankings. In addition, the independent samples t-test showed statistically significant differences in means values of responses from clients and contractors for eight attributes. Based on factor analysis, 19 important attributes (median value greater than or equal to four) were classified into 4 latent factors – (1) poor-quality assurance and control, (2) unethical practices, (3) design and drawing errors, and (4) knowledge and skills gap.

Originality/value

Evaluating the factors affecting the quality of construction projects will help clients, government departments, and construction practitioners improve the construction quality management practices. The findings will also inform the policies and procedures of international aid providers.

Details

Engineering, Construction and Architectural Management, vol. 30 no. 10
Type: Research Article
ISSN: 0969-9988

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Article
Publication date: 29 April 2014

Leila Karimi, Brad Gilbreath, Tae-Yeol Kim and Matthew J. Grawitch

– The purpose of this paper is to investigate the extent to which supervisor behavior is associated with employees’ job neglect.

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Abstract

Purpose

The purpose of this paper is to investigate the extent to which supervisor behavior is associated with employees’ job neglect.

Design/methodology/approach

The paper investigates the extent to which supervisor behavior is associated with employees’ job neglect.

Findings

Results from hierarchical regression analyses support the hypothesis that both positive and negative supervisor behaviors have significant effects on job neglect. Negative supervisor behavior was more strongly associated with job neglect than positive supervisor behavior.

Research limitations/implications

Changing the style of supervision might help to reduce job neglect of employees, benefitting the organization by reducing the associated costs of job neglect and counterproductive behavior.

Originality/value

The findings provide additional evidence for the important effects supervisors can have on employees. They also indicate that – in addition to studying abusive supervision – there is a need to consider the effects of a broad spectrum of supervisor behavior.

Details

Leadership & Organization Development Journal, vol. 35 no. 3
Type: Research Article
ISSN: 0143-7739

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Article
Publication date: 29 October 2021

Hannan Amoozad Mahdiraji, Moein Beheshti, Seyed Hossein Razavi Hajiagha, Niloofar Ahmadzadeh Kandi and Hasan Boudlaie

Due to the political, economic and infrastructure barriers and risks that international entrepreneurs (IEs) face when researching an emerging economy's agrifood sector, this…

305

Abstract

Purpose

Due to the political, economic and infrastructure barriers and risks that international entrepreneurs (IEs) face when researching an emerging economy's agrifood sector, this research aims to identify the major barriers, analyse their relationships, quantify their importance, classify and rank them. Thus, the IEs will gain a better understanding and vision of their decision-making processes in this era.

Design/methodology/approach

To do this, the authors first created a list of barriers to entry for IEs into Iran's rising economy's agrifood industry. Following that, a multi-layer decision-making approach was developed and implemented to accomplish the research objectives. The first stage utilized a hybrid of interpretive structural modelling (ISM) and cross-impact matrix multiplication applied to classification (MICMAC) to depict the level-based conceptual model and classification of the IEs’ obstacles to entry into the agrifood sector. Following that, a hybrid decision-making trial and evaluation laboratory (DEMATEL), and analytic network process (ANP) called DANP was utilized to present a causal relationship between the barriers, identify their causes and effects, and also quantify the relevance of each barrier.

Findings

After employing the multi-layer decision-making approach, the results demonstrated that fundamental limitations, including infrastructure and technology limitations, are the most critical barriers alongside policy factors encompassing governmental support and access to global or regional economy/market. According to the results, innovation and economic sustainability of the agrifood supply chain also matter. All of these critical barriers are intertwined and should be planned and solved simultaneously. Furthermore, based on DANP results, the sustainability pillars (economy, environment, society), besides the low efficiency of the agrifood sector in Iran, should be investigated further for future policy makings.

Originality/value

A hybrid multi-layer decision-making approach has been used for analysing the barriers of investment in the agrifood sector of the emerging economy of Iran for the international entrepreneurs. Moreover, the authors provide implications and insights for IEs and officials for decision-making in the future.

Details

British Food Journal, vol. 124 no. 7
Type: Research Article
ISSN: 0007-070X

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Book part
Publication date: 11 November 2024

Sumesh Singh Dadwal, Gordon Bowen, Hamid Jahankhani, Vipin Nadda and Pawan Kumar

In the era of generative artificial intelligence (AI), big data analytics, business analytics and mega global digital corporations, the profession of marketing is at a crossroads…

Abstract

In the era of generative artificial intelligence (AI), big data analytics, business analytics and mega global digital corporations, the profession of marketing is at a crossroads between ‘Prosumer-Marketing’ and ‘Market Grooming’. Whereas prosumer (producers + consumers) marketing means a process of exchange in which producers and consumers have equal, just, control, voluntary, fully aware engagement and control over the process of design, development and exchange of goods, services and values. On the other hand, ‘Market Grooming’ is a one-sided, unethical process of conditioning or influencing, deceiving, or persuading or manipulating and even exploiting customers by the marketing organisations, without customers' voluntary consent, permissions, awareness, etc. As the consumers have asymmetric access to information, asymmetric and lesser favourable levels of control, and lesser power in the process of exchange, as customers trust the marketers or are dependent on popular brands, the markers tend to exploit the situation. The process of market grooming has become easier due to the power of AI, generative AI, ChatGPT, TikToketing, machine learning and big data analytics leading to the development of sophisticated predictive models and persuasive models. This chapter explores and analyses a range of techniques in marketing such as permission marketing, flywheel marketing, subliminal marketing, neuromarketing, cyberstalking, ethical marketing, etc., in the era of AI. The arguments for high concerns pertaining to potential market grooming are supported by theories of ethics, theories of digital marketing and models of AI. The chapter concludes with some strategic recommendations.

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Article
Publication date: 30 August 2024

Mark Kirby, Funmilayo Ebun Rotimi and Nicola Naismith

The New Zealand (NZ) construction industry significantly impacts the country's economy and is one of the largest sectors in terms of total employment. However, a persistent and…

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Abstract

Purpose

The New Zealand (NZ) construction industry significantly impacts the country's economy and is one of the largest sectors in terms of total employment. However, a persistent and pressing need for improvement exists. Meeting the ongoing demand for housing and urban development requires enhancing residential construction productivity. The purpose of this paper is to determine what factors improve construction productivity in the NZ residential construction sector.

Design/methodology/approach

Data were obtained from construction industry bodies using a semi-structured online questionnaire survey. From 305 online questionnaires administered, 106 samples were completed by residential industry construction professionals across NZ. The data were analysed using descriptive and inferential statistics to establish the importance of empirical factors for improving construction productivity in the NZ residential construction sector.

Findings

The Garrett ranking technique revealed this study's top five factors for enhancing construction productivity: adequate design, communication, quality management (QM), supervision and organizational training. Other factors, such as unskilled workers, skilled workers, reworks and employee motivation, ranked less important.

Research limitations/implications

While providing a valuable exploration of factors that can positively impact residential construction productivity in NZ, this study contains certain limitations. The study's focus on a specific geographic location and a small sample size (n = 106) may restrict the generalizability of its findings to other regions or countries. Furthermore, the reliance on self-reported data from industry professionals introduces the possibility of bias or inaccuracies in the results. In addition, this study did not investigate the potential influence of external factors, such as economic conditions or regulatory changes, on residential construction productivity. Despite these limitations, this study presents a foundation for future research on this topic. Future research could address these limitations by conducting multi-country studies and using objective productivity measures to provide a broader context. In addition, open-ended questions could be used to collect more detailed qualitative data, enhancing this study's dependability. This methodological constraint could have omitted important experiential nuances, which could be explored in future research to provide more comprehensive and rigorous findings.

Practical implications

Research studies indicate that several construction productivity factors have remained unchanged for over three decades (Arditi and Mochtar, 1996; Hasan et al., 2018). The implications of this study are significant for the residential sector in NZ. By identifying the key factors that can improve productivity in the sector, such as complete design and specifications, effective communication, quality management, adequate supervision, training, skilled labour and employee motivation, this study provides valuable insights for industry practitioners and policymakers. It expands the existing productivity literature around factors for improving NZ residential construction productivity. One important implication of this study is the link between QM and improved productivity, highlighting the significance of strategic organizational investments in QM and the added opportunity presented to policymakers concerning industry-wide improvements. Moreover, the findings suggest that investing in worker training is essential. Ensuring workers possess the necessary skills and knowledge to perform their tasks efficiently can enhance productivity and project outcomes. In conclusion, this study's findings emphasize the factors that can improve construction productivity in residential projects in NZ, ultimately leading to improved outcomes for all stakeholders.

Originality/value

This research offers a unique perspective on improving residential construction productivity in NZ by identifying and analysing specific factors that can enhance efficiency across the sector. It provides novel findings and valuable insight into possible organizational improvement strategies yet considered in the NZ residential sector.

Details

Journal of Engineering, Design and Technology , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 28 November 2023

Kujtim Hameli, Lekë Ukaj and Lum Çollaku

This study aims to investigate the impact of emotional intelligence on work engagement by exploring the mediating roles of self-efficacy and psychological empowerment in this…

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Abstract

Purpose

This study aims to investigate the impact of emotional intelligence on work engagement by exploring the mediating roles of self-efficacy and psychological empowerment in this relationship.

Design/methodology/approach

Using the survey method, data were collected through both physical and online means. The final sample comprised 304 teachers working in elementary, middle and high schools. Structural equation modeling (SEM) analysis, utilizing IBM Amos version 26, was employed to assess the hypothesized model.

Findings

The study's results revealed that emotional intelligence does not exert a direct impact on work engagement. Additionally, self-efficacy was not found to mediate the relationship between emotional intelligence and work engagement. However, psychological empowerment emerged as a mediating factor in this context. Furthermore, self-efficacy and psychological empowerment concurrently demonstrated significant mediation of the relationship between emotional intelligence and work engagement.

Research limitations/implications

The findings underscore the significance of teachers' emotional intelligence, suggesting that it can have profound implications for their work engagement through the mediating mechanisms of self-efficacy and psychological empowerment. Educational principals and administrators are encouraged to prioritize the enhancement of teachers' psychological empowerment, recognizing it as a pivotal link between teachers' emotional intelligence and work engagement.

Originality/value

This study contributes to the field by comprehensively examining the mediating roles of self-efficacy and psychological empowerment, addressing prior empirical gaps, and enriching the understanding of how emotional intelligence influences work engagement within the educational sphere.

Details

EuroMed Journal of Business, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1450-2194

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Book part
Publication date: 9 May 2023

André Renz and Romy Hilbig

During the Coronavirus crisis (COVID-19) that started in 2019 and at the extensive quarantine regulations, educational institutions, companies, and individuals have reacted by…

Abstract

During the Coronavirus crisis (COVID-19) that started in 2019 and at the extensive quarantine regulations, educational institutions, companies, and individuals have reacted by shifting their teaching and learning activities to virtual spaces. Yet, although the use of online learning has increased, it has not been able to achieve the long-promised transformative effect. The COVID-19 crisis has the potential to boost online education overall or at least enable better preparation of the system for the next crisis. Ultimately, to make a digital transformation sustainable, appropriate skills are required. In this study, we adapt the dynamic capabilities foundations creating a theoretical approach to explain how educational institutions have responded to the changing environmental conditions during the COVID-19 pandemic.

Details

Beyond the Pandemic? Exploring the Impact of COVID-19 on Telecommunications and the Internet
Type: Book
ISBN: 978-1-80262-050-4

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Article
Publication date: 7 June 2023

Mohammad Mehdi Mohammadi, Mehdi Safari Gerayli, Maryam Shahri, Hasan Valiyan and Farhad Dehdar

The citizen-shareholder approach in the capital market is considered a knowledge-enhancing and emerging concept in financial and accounting offerings. Its reliable background in…

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Abstract

Purpose

The citizen-shareholder approach in the capital market is considered a knowledge-enhancing and emerging concept in financial and accounting offerings. Its reliable background in management and human sciences makes it an essential basis for protecting the interests of shareholders and investors. Shareholders are considered a necessary part of the social platforms that are companies and regulatory institutions in the capital market; beyond being obligated to protect their material and intellectual rights, they are responsible for developing norms and facilitating investment values and gaining trust through mutual interactions based on respect for their interests. The purpose of this paper is to perform interactive qualitative analysis of the requirements for protecting the rights of citizens of capital market shareholders.

Design/methodology/approach

The methodology of the research is mixed, so that in the qualitative part, through content screening, the dimensions related to the protection of the citizen rights of the capital market shareholders were identified through a systematic review of 10 research in the period of 2017–2022. Then, the reliability of the specified dimensions was examined through Delphi analysis; in the quantitative part of the research, the criteria identified through the pairwise comparison matrix were first determined by the level of their relationships to determine based on the pattern of systemic representation of drivers and the consequences of requirements to protect the rights of citizens of capital market shareholders.

Findings

The research results in the qualitative part indicated the existence of 12 primary themes; during the two stages of Delphi analysis, three themes were removed, and a total of nine themes entered the quantitative phase. The results in a quantitative part indicate the creation of specialized and active committees of the board of directors as the primary driver and the reliability and timely disclosure of information in the long term as a systemic consequence.

Originality/value

To the best of the authors’ knowledge, this is the first research that presents the new concept of citizen shareholders to strengthen the requirements of protecting the rights of shareholders in the capital market while developing new theoretical literature.

Details

Qualitative Research in Financial Markets, vol. 16 no. 2
Type: Research Article
ISSN: 1755-4179

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