Search results

A major obstacle regarding the measurement of an organization's sustainability and accountability in the space economy is defining the context and boundaries of commercial activity in outer space. Here, we introduce an ecosystem framework to address this obstacle. We utilize this framework to analyze the space mining sector. Our ecosystem framework sets the space mining sector's boundaries and helps a firm identify key stakeholders, activities, policies, norms and common pool resources in that sector and the interactions between them; a significant step in structuring how to measure space sustainability and accountability.

Borrowing theories and perspectives from a wide range of academic fields, this paper conducts a comprehensive context analysis of the space mining ecosystem.

Using our ecosystem framework to define the context and set boundaries for the space mining sector allowed us to identify sustainability-related issues in the sector and offer roadmaps to develop sustainability measures and standards.

To the best of the authors’ knowledge, this is one of the first papers to introduce a framework to define boundaries in the global space economy and provides a tool to understand, measure and evaluate the space mining sector's environmental, social and economic issues.

Drawing on the reasoned action theory, this study aims to examine the impact of environmental knowledge (EK) and environmental sustainability performance (EP) on environmental behavior (EB) mediated by environmental attitude (ATT). Furthermore, to examine the moderating effect of environmental advertising (ADD) on the indirect relationship between EP and EB, mediated by ATT on the one hand, and EK on EB, on the other hand, mediated by ATT.

The data were gathered within an international context for passengers from North African countries (NAC) (Egypt, Algeria, Tunisia, Libya, Morocco and Sudan) using primary quantitative data from online and self-administered questionnaires. A total of 1,052 questionnaires were collected from passengers who traveled through Egyptian airports. The collected data were analyzed through covariance-based structural equation modeling.

The findings indicated that ATT moderates the relationship between environmental knowledge and behavior. In addition, ATT mediates the airports' environmental behavior and environmental sustainability performance. Moreover, ADD moderates the indirect association between EP and individuals' environmental knowledge and behavior through the mediated effect of ATT.

This research output will help extend the theory’s scope by conceptualizing its abstract ideas using research variables and applying them in NAC countries. This can be a milestone for altering individuals' behavior toward the environment in airports.

This study aims to assist airport authorities in the development of standards for enhancing environmental performance. Enhancing environmental issues is of utmost importance, especially in the context of airports, which have been a subject of significant environmental concern. This study examined the environmental practices of airport passengers in NAC, given their significant role as the primary source of greenhouse gas emissions on the African continent. The present approach has the potential to be utilized in modifying airport conduct and enhancing stakeholder engagement, specifically within the context of NAC.

The objective of this study is to enhance the relationship between nature and humans by endeavoring to modify human attitudes toward the environment. The objective of this initiative is to bridge the current disparity in the socio-environmental connection by fostering environmental consciousness among individuals who utilize airport facilities. The objective will be accomplished by the construction of a theoretical framework that integrates crucial elements acknowledged for their substantial influence on altering human attitudes, thus fostering a greater sense of environmental consciousness and ultimately improving societal well-being.

Since the global supply chain prioritizes environmental transportation systems, this study provides a conceptual framework for airport authorities to develop and create policies to push air passengers' behavior toward environmental practices in NAC.

Flow induced by rotating disks is of great practical importance in several engineering applications such as rotating heat exchangers, turbine disks, pumps and many more. The present research has been freshly displayed regarding the implementation of an engine oil-based Casson tri-hybrid nanofluid across a rotating disk in mass and heat transferal developments. The purpose of this study is to contemplate the attributes of the flowing tri-hybrid nanofluid by incorporating porosity effects and magnetization and velocity slip effects, viscous dissipation, radiating flux, temperature slip, chemical reaction and activation energy.

The articulated fluid flow is described by a set of partial differential equations which are converted into one set of higher-order ordinary differential equations (ODEs) by using convenient conversions. The numerical solution of this transformed set of ODEs has been spearheaded by using the effectual bvp4c scheme.

The acquired results show that the heat transmission rate for the Casson tri-hybrid nanofluid is intensified by, respectively, 9.54% and 11.93% when compared to the Casson hybrid nanofluid and Casson nanofluid. Also, the mass transmission rate for the Casson tri-hybrid nanofluid is augmented by 1.09% and 2.14%, respectively, when compared to the Casson hybrid nanofluid and Casson nanofluid.

The current investigation presents an educative response on how the flow profiles vary with changes in the inevitable flow parameters. As per authors’ knowledge, no such scrutinization has been carried out previously; therefore, our results are novel and unique.

Plasma technology has become of great interest in a wide variety of industrial and domestic applications. Moreover, the application of plasma in the domestic field has increased in recent years due to its applications to surface treatment and disinfection. In this context, there is a significant need for versatile power generators able to generate a wide range of output voltage/current ranging from direct current (DC) to tens of kHz in the range of kVs. The purpose of this paper is to develop a highly versatile power converter for plasma generation based on a multilevel topology.

This paper proposes a versatile multilevel topology able to generate versatile output waveforms. The followed methodology includes simulation of the proposed architecture, design of the power electronics, control and magnetic elements and test laboratory tests after building an eight-level prototype.

The proposed converter has been designed and tested using an experimental prototype. The designed generator is able to operate at 10 kVpp output voltage and 10 kHz, proving the feasibility of the proposed approach.

The proposed converter enables versatile waveform generation, enabling advanced studies in plasma generation. Unlike previous proposals, the proposed converter features bidirectional operation, allowing to test complex reactive loads. Besides, complex waveforms can be generated, allowing testing complex patterns for optimized cold-plasma generation methods. Besides, unlike transformer- or resonant-network-based approaches, the proposed generator features very low output impedance regardless the operating point, exhibiting improved and reliable performance for different operating conditions.

This paper aims to comprehensively explore techniques for reducing solution time in finite element analysis (FEA), addressing the critical need for expediting computations to facilitate agile design exploration within project timelines.

Drawing from a wide array of literature sources, this paper synthesizes and analyzes various methodologies used to enhance the efficiency of FEA. Techniques are scrutinized in terms of their applicability, effectiveness and potential limitations.

The review signifies application of linear assumptions across multiple facets of analysis and delves into matrix order reduction strategies, geometry simplification, symmetry exploitation, submodeling and mesh attribute control. It reveals how these techniques can effectively reduce computational burdens while maintaining acceptable levels of accuracy.

While this review provides a comprehensive overview of existing efficiency enhancement techniques in FEA, it acknowledges inherent limitations of any synthesis-based study. Future research should focus on refining these methodologies.

The insights provided in this paper offer practical guidance for structural engineers and researchers seeking to optimize FEA workflows. By implementing these techniques, practitioners can expedite solution times and enhance their ability to explore design alternatives efficiently ultimately leading to cost savings and more robust structures.

This review contributes to the existing literature by offering a comprehensive synthesis of efficiency enhancement techniques in FEA. By highlighting the originality and value of each discussed methodology, this paper provides a roadmap for future research and practical implementation in the field of structural engineering.

University-industry collaboration studies have placed greater emphasis on intrinsic motivators that drive academic researchers to pursue collaboration. This paper explores the relationship between spiritual motivation and collaboration intentions mediated the antecedents of university-level collaboration through theories of self-determination and planned behaviour. This study was conducted to validate the proposed relationship between spirituality and academic researchers in the field of engineering affiliated with higher educational institutions in India.

This study surveyed 242 participants and utilised structural equation modelling. Research has found that the beneficial relationship between spiritual motivation and collaboration intentions is mediated by attitudes and perceived behavioural control. This study represents a quantitative investigation within the realm of university-industry collaboration, which aims to document the ways in which spiritual motivation can augment collaboration with industry. The study employs self-determination theory and the theory of planned behaviour to elucidate the underlying mechanism to support entrepreneurial debate.

This study identified attitude and perceived behavioural control as mediators in the relationship between spiritual motivation and collaboration intentions.

The results of this study provide additional support for existing theories and present a diverse perspective on the intrinsic motivation of academic researchers to adopt UIC.